Thursday, November 20, 2008
Diabetes and Pollution
To yet again highlight the ever increasing dangers of pollution, this article puts forward a very worrying hypothesis that is cause for concern. This is not the first study to find a link between diabetes and pollution and it will not be the last.
Potassium, Sodium, and Blood Pressure
Low Potassium is linked to high blood pressure
Most of us have heard about the dangers of excessive salt consumption in relation to blood pressure. While salt consumption needs to be carefully monitored it is equally as important to ensure that we receive adequate potassium intake. This can be quite a challenge as recommended potassium intake is quite high. Bananas, potatoes, Tomato juice, orange juice, are all good sources of potassium. This article, from the ever reliable NIH institute, provides a good overview of potassium and its dietary sources. Note the daily requirement for potassium is a whooping 4.7 grams. To achieve this, have a look at this site for more detailed guidelines on potassium dietary sources. Look at the table at the bottom of the page. They have excluded meat sources but these are also valuable sources of potassium.
Remember, the potassium - salt(ie sodium) balance is very important, so if you eat lots of processed food, which is typically far too high in sodium and\or salt, you need to counter balance this with substantial potassium intake.
Most of us have heard about the dangers of excessive salt consumption in relation to blood pressure. While salt consumption needs to be carefully monitored it is equally as important to ensure that we receive adequate potassium intake. This can be quite a challenge as recommended potassium intake is quite high. Bananas, potatoes, Tomato juice, orange juice, are all good sources of potassium. This article, from the ever reliable NIH institute, provides a good overview of potassium and its dietary sources. Note the daily requirement for potassium is a whooping 4.7 grams. To achieve this, have a look at this site for more detailed guidelines on potassium dietary sources. Look at the table at the bottom of the page. They have excluded meat sources but these are also valuable sources of potassium.
Remember, the potassium - salt(ie sodium) balance is very important, so if you eat lots of processed food, which is typically far too high in sodium and\or salt, you need to counter balance this with substantial potassium intake.
Stop Killing the Frogs
There is a prevailing mythology that if bodily concentrations of a particular compound are below the "safety threshold" then no damage is being done. Even a basic understanding of biological processes should reveal how dangerous and misleading that notion is. As this recent indicates, cumulative exposure of various compounds that are well below the safety threshold for each compound are more than capable of killing amphibians. We should all be very worried about the amount of junk humanity is pouring into the environment because this has serious implications not only for the other animals but as increasing numbers of studies are indicating this also has serious implications for human health.
Marijuana and Dementia
Over the years there have been multiple studies indicating the potential of cannabinoids across a wide range of conditions. This latest study provides further weight as to the therapeutic potential of cannabinoids. It is high time that the public was made aware of the considerable therapeutic potential of these compounds. As for the psychosis\schizophrenia risk, that has been too much overblown and the risk is virtually negligible post 21 years of age. The reasons for this therapeutic potential are:
- The two principal cannabinoids, THC and cannabidiol, have very strong antioxidant capacity.
- These two compounds are lipophilic, that is lipid soluble, hence will remain in the body for extended periods. For pot smokers, typical wash out periods are 90% after one week, though this can greatly vary.
- Both of these compounds target specific receptors. THC will target CB1 and to a lesser extent CB2(controversial), while cannabidiol is very specific for CB2 and hence is non-psychoactive.
- Both compounds will bind to the anion site of ACHe, an enzyme that breaks down acetylcholine. This neurotransmitter is markedly reduced in some dementias, particularly Alzheimers.
- ACHe is also strongly implicated in amyloid production, both cannabinoids reduce the production of amyloid, an early step in Alzheimers because this production seems contingent on the anion site.
- Activation of the CB2 receptor limits the expression of pro-inflammatory cytokines, excess production of these cytokines being implicated in everything from atherosclerosis to cancer to dementia.
Sunday, November 9, 2008
Vitamin B3 and Alzheimers Disease
9/11/2008 4:37PM
Vitamin B3 and Alzheimers Disease
Nicotinamide is a form of Vitamin B3. This is a promising study because this compound was found to target a key and early initiator of amyloid plaque formation in the brain. That process is tau phosphorylation which is implicated in many neurodegenerative conditions. Nicotinamide can be purchased as supplement and is generally safe but at very high doses can be toxic.
The Science Daily news release is available here.
The Journal of Neuroscience, November 5, 2008, 28(45):11500-11510; doi:10.1523/JNEUROSCI.3203-08.2008
Nicotinamide Restores Cognition in Alzheimer's Disease Transgenic Mice via a Mechanism Involving Sirtuin Inhibition and Selective Reduction of Thr231-Phosphotau
Kim N. Green,1 Joan S. Steffan,2 Hilda Martinez-Coria,1 Xuemin Sun,3 Steven S. Schreiber,3,5 Leslie Michels Thompson,1,2,4 and Frank M. LaFerla1
Departments of 1Neurobiology and Behavior, 2Psychiatry and Human Behavior, 3Neurology, 4Biological Chemistry, and 5Anatomy and Neurobiology, University of California, Irvine, Irvine, California 92697-4545
Correspondence should be addressed to Frank M. LaFerla, Department of Neurobiology and Behavior, University of California, Irvine, 1109 Gillespie Neuroscience Building, Irvine, CA 92697-4545. Email: laferla@uci.edu
Memory loss is the signature feature of Alzheimer's disease, and therapies that prevent or delay its onset are urgently needed. Effective preventive strategies likely offer the greatest and most widespread benefits. Histone deacetylase (HDAC) inhibitors increase histone acetylation and enhance memory and synaptic plasticity. We evaluated the efficacy of nicotinamide, a competitive inhibitor of the sirtuins or class III NAD+-dependent HDACs in 3xTg-AD mice, and found that it restored cognitive deficits associated with pathology. Nicotinamide selectively reduces a specific phospho-species of tau (Thr231) that is associated with microtubule depolymerization, in a manner similar to inhibition of SirT1. Nicotinamide also dramatically increased acetylated -tubulin, a primary substrate of SirT2, and MAP2c, both of which are linked to increased microtubule stability. Reduced phosphoThr231-tau was related to a reduction of monoubiquitin-conjugated tau, suggesting that this posttranslationally modified form of tau may be rapidly degraded. Overexpression of a Thr231-phospho-mimic tau in vitro increased clearance and decreased accumulation of tau compared with wild-type tau. These preclinical findings suggest that oral nicotinamide may represent a safe treatment for AD and other tauopathies, and that phosphorylation of tau at Thr231 may regulate tau stability.
Vitamin B3 and Alzheimers Disease
Nicotinamide is a form of Vitamin B3. This is a promising study because this compound was found to target a key and early initiator of amyloid plaque formation in the brain. That process is tau phosphorylation which is implicated in many neurodegenerative conditions. Nicotinamide can be purchased as supplement and is generally safe but at very high doses can be toxic.
The Science Daily news release is available here.
The Journal of Neuroscience, November 5, 2008, 28(45):11500-11510; doi:10.1523/JNEUROSCI.3203-08.2008
Nicotinamide Restores Cognition in Alzheimer's Disease Transgenic Mice via a Mechanism Involving Sirtuin Inhibition and Selective Reduction of Thr231-Phosphotau
Kim N. Green,1 Joan S. Steffan,2 Hilda Martinez-Coria,1 Xuemin Sun,3 Steven S. Schreiber,3,5 Leslie Michels Thompson,1,2,4 and Frank M. LaFerla1
Departments of 1Neurobiology and Behavior, 2Psychiatry and Human Behavior, 3Neurology, 4Biological Chemistry, and 5Anatomy and Neurobiology, University of California, Irvine, Irvine, California 92697-4545
Correspondence should be addressed to Frank M. LaFerla, Department of Neurobiology and Behavior, University of California, Irvine, 1109 Gillespie Neuroscience Building, Irvine, CA 92697-4545. Email: laferla@uci.edu
Memory loss is the signature feature of Alzheimer's disease, and therapies that prevent or delay its onset are urgently needed. Effective preventive strategies likely offer the greatest and most widespread benefits. Histone deacetylase (HDAC) inhibitors increase histone acetylation and enhance memory and synaptic plasticity. We evaluated the efficacy of nicotinamide, a competitive inhibitor of the sirtuins or class III NAD+-dependent HDACs in 3xTg-AD mice, and found that it restored cognitive deficits associated with pathology. Nicotinamide selectively reduces a specific phospho-species of tau (Thr231) that is associated with microtubule depolymerization, in a manner similar to inhibition of SirT1. Nicotinamide also dramatically increased acetylated -tubulin, a primary substrate of SirT2, and MAP2c, both of which are linked to increased microtubule stability. Reduced phosphoThr231-tau was related to a reduction of monoubiquitin-conjugated tau, suggesting that this posttranslationally modified form of tau may be rapidly degraded. Overexpression of a Thr231-phospho-mimic tau in vitro increased clearance and decreased accumulation of tau compared with wild-type tau. These preclinical findings suggest that oral nicotinamide may represent a safe treatment for AD and other tauopathies, and that phosphorylation of tau at Thr231 may regulate tau stability.
A "Fat Burning" Drug?
Experimental Drug Spurs Fat Burning
This is all becoming rather silly. That so many valuable research resources are being wasted on what is essentially a behavioral problem is a poor reflection on society and the state of biomedical research. The last fat burning drug promising miracles was fenfluramine. It was discontinued in 1997 because it was found to induce heart valve damage, this damage lasting years after use was ceased.
This drug targets SIRT1, a gene transcription regulator that is strongly associated with the beneficial effects of caloric restriction. A word of warning about the caloric restriction craze: recent studies have indicated that it will probably not prolong life in humans and it does carry some risks, including infertility, immunosuppression, hypoglycemia, and there is some suggestion it may damage the brain over the long term. Not surprising really, animals living in cages on CR is something entirely different from the real world experience. I suspect this drug will never reach the market.
To use drugs to address what is essentially a behavioral problem is both dumb and dangerous. Sure, it can be very difficult to lose weight. Many years ago I began to pile on the weight. It took time but I now have reduced my weight to a very good level. I could probably lose a few more kilos but I'm not obsessive about weight, in fact I think the Body Mass Index is silly and misleading. What many are loathe to say is that being a little overweight is probably better than being underweight. Some studies do support this.
If you are gaining weight don't run to the doctor for a magic bullet. In this age of ballooning health care costs and innumerable accounts of so called "scientifically tested" drugs proving to have worrying side effects prudence and common sense dictates that we should take charge of our health instead of seeking magic bullets from the biomedicine industry. You know what you have to do: change your lifestyle and diet. Don't try to lose weight quickly, don't diet, change your lifestyle and diet so the weight is gradually shed until you reach the weight you think is good for your body type. The BMI is a useful guide but don't take it as an absolute. There are no dietary or health secrets and anyone who tells you differently is probably trying to sell you something.
This is all becoming rather silly. That so many valuable research resources are being wasted on what is essentially a behavioral problem is a poor reflection on society and the state of biomedical research. The last fat burning drug promising miracles was fenfluramine. It was discontinued in 1997 because it was found to induce heart valve damage, this damage lasting years after use was ceased.
This drug targets SIRT1, a gene transcription regulator that is strongly associated with the beneficial effects of caloric restriction. A word of warning about the caloric restriction craze: recent studies have indicated that it will probably not prolong life in humans and it does carry some risks, including infertility, immunosuppression, hypoglycemia, and there is some suggestion it may damage the brain over the long term. Not surprising really, animals living in cages on CR is something entirely different from the real world experience. I suspect this drug will never reach the market.
To use drugs to address what is essentially a behavioral problem is both dumb and dangerous. Sure, it can be very difficult to lose weight. Many years ago I began to pile on the weight. It took time but I now have reduced my weight to a very good level. I could probably lose a few more kilos but I'm not obsessive about weight, in fact I think the Body Mass Index is silly and misleading. What many are loathe to say is that being a little overweight is probably better than being underweight. Some studies do support this.
If you are gaining weight don't run to the doctor for a magic bullet. In this age of ballooning health care costs and innumerable accounts of so called "scientifically tested" drugs proving to have worrying side effects prudence and common sense dictates that we should take charge of our health instead of seeking magic bullets from the biomedicine industry. You know what you have to do: change your lifestyle and diet. Don't try to lose weight quickly, don't diet, change your lifestyle and diet so the weight is gradually shed until you reach the weight you think is good for your body type. The BMI is a useful guide but don't take it as an absolute. There are no dietary or health secrets and anyone who tells you differently is probably trying to sell you something.
Antioxidants - A Risk Benefit Profile
Antioxidants are all the rage these days. Paradoxically, while there are many in vitro studies demonstrating potential benefits from antioxidants, and many studies indicating their utility in various pathologies, there is scant evidence that antioxidant supplementation prolongs life.
I have concerns about the absorbing huge doses of antioxidants. Oxidation is an intrinsic and vital physiological process, filling up your body with antioxidants may sound like a good idea but how often have we been subjected to the latest nutrition craze only to find that it was nonsense? Far too many times, there needs to be much caution in the use of antioxidants. This recent study highlights that while antioxidants have considerable therapeutic promise, indiscriminate use of antioxidants can also lead to pathological processes.
One thing not mentioned in this study but is very important is the use of alpha tocopherol, typically and misleading referred to as Vitamin E. There are in fact a number of types of vitamin E and high consumption of alpha tocopherol can reduce the concentrations of gamma tocopherol and delta tocopherol, both of which are better variants than alpha tocopherol. . This may explain why some studies have found that high dosages of alpha tocopherol can increase mortality. The reason why most vitamin E supplements only contain alpha tocopherol is simple: it is the cheapest to manufacture. If you want a good source of vitamin E use wheatgerm. Note what the below study found in relation to wheatgerm:
Note that last sentence, that the antioxidants in wheat germ "recover" their antioxidant activity. Now whether or not this happens in the body is another question but given that wheat germ is cheap and a valuable nutrient source why bother with all those expensive supplements?
This study also highlights that certain antioxidants, at high doses, can actually induce oxidation. Ever since that now famous study on beta carotene which found it increased the rate of lung cancer in smokers(as if that were possible!) I have harbored suspicions that beta carotene should not be added to multi vitamins. Smokers should definitely avoid beta carotene in vitamin pills and problem be careful about the intake from natural sources. As for non smokers, the data is equivocal. Beta carotene does not appear to be a causative factor for or against developing cancer.
Ascorbic acid, a variant of vitamin C, appears to be a double edged sword. At high doses it can stimulate the production reactive oxygen species, particularly in the presence of free iron, the latter often being present in inflammatory conditions. Mega dosing of vitamin C is a waste of money and can damage the gut. Once tissue saturation of vitamin C is achieved there is little point in swallowing vitamin C tablets because it will not pass the gut wall. Smokers should increase their intake of vitamin C has it has been shown to help preserve vitamin E levels. As with most antioxidants, it is generally better to consume these throughout the day because this will help maintain tissue levels through the course of the day, whereas consuming antioxidant rich foods or supplements at one time of the day will lead to depletion until topping up occurs at the next meal.
The flip side of megadosing for vitamin C is recent studies which found that intravenous injections of vitamin C may have therapeutic use in treating some cancers.
The below study can be downloaded at this site.
Reading
Article
The role of antioxidant supplement in immune system, neoplastic,
and neurodegenerative disorders: a point of view for an assessment
of the risk/benefit profile
Authors
Daria Brambilla1, Cesare Mancuso2, Mariagrazia Rita Scuderi1, Paolo Bosco3,
Giuseppina Cantarella1, Laurence Lempereur1, Giulia Di BenedettoLL0000001,
Salvatore Pezzino1 and Renato Bernardini*1
Journal
Nutrition Journal 2008, 7:29 doi:10.1186/1475-2891-7-29
Location
Life\Nutrition\
Date obtained
2/11/2008
Date Read
7/11/2008
Date to Review
Web Page
http://www.nutritionj.com/content/7/1/29
Keywords
Printed
Notes
Abstract
This review will discuss some issues related to the risk/benefit profile of the use of dietary antioxidants. Thus, recent progress regarding the potential benefit of dietary antioxidants in the treatment of chronic diseases with a special focus on immune system and neurodegenerative disorders will be discussed here. It is well established that reactive oxygen species (ROS) play an important role in the etiology of numerous diseases, such as atherosclerosis, diabetes and cancer. Among the physiological defense system of the cell, the relevance of antioxidant molecules, such as glutathione and vitamins is quite well established. Recently, the interest of researchers has, for example, been conveyed on antioxidant enzyme systems, such as the heme oxygenase/biliverdin reductase system, which appears modulated by dietary antioxidant molecules, including polyphenols and beta-carotene. These systems possibly counteract oxidative damage very efficiently and finally modulate the activity of oxidative phenomena occurring, for instance, during pathophysiological processes. Although evidence shows that antioxidant treatment results in cytoprotection, the potential clinical benefit deriving from both nutritional and supplemental antioxidants is still under wide debate. In this line, the inappropriate assumption of some lipophylic vitamins has been associated with increased incidence of cancer rather than with beneficial effects.
I have concerns about the absorbing huge doses of antioxidants. Oxidation is an intrinsic and vital physiological process, filling up your body with antioxidants may sound like a good idea but how often have we been subjected to the latest nutrition craze only to find that it was nonsense? Far too many times, there needs to be much caution in the use of antioxidants. This recent study highlights that while antioxidants have considerable therapeutic promise, indiscriminate use of antioxidants can also lead to pathological processes.
One thing not mentioned in this study but is very important is the use of alpha tocopherol, typically and misleading referred to as Vitamin E. There are in fact a number of types of vitamin E and high consumption of alpha tocopherol can reduce the concentrations of gamma tocopherol and delta tocopherol, both of which are better variants than alpha tocopherol. . This may explain why some studies have found that high dosages of alpha tocopherol can increase mortality. The reason why most vitamin E supplements only contain alpha tocopherol is simple: it is the cheapest to manufacture. If you want a good source of vitamin E use wheatgerm. Note what the below study found in relation to wheatgerm:
Intriguingly, the combined treatment with wheat germ and vitamin C profoundly inhibited metastasis formation in various tumor models of different origin (Lewis lung carcinoma, B16 melanoma and human colon carcinoma xenografts [HCR25]) [61]. On the contrary, wheat germ had no toxicity on peripheral blood leukocytes (PBLs) at doses that affected tumor cells. The crude powder extract of fermented wheat germ inhibits nucleic acid ribose synthesis primarily through the non-oxidative steps of the pentose cycle [60]. Curiously, another quinone compound, carnosic acid quinone, like wheat germ, recovers potent antioxidant activity upon standing [62].
Note that last sentence, that the antioxidants in wheat germ "recover" their antioxidant activity. Now whether or not this happens in the body is another question but given that wheat germ is cheap and a valuable nutrient source why bother with all those expensive supplements?
This study also highlights that certain antioxidants, at high doses, can actually induce oxidation. Ever since that now famous study on beta carotene which found it increased the rate of lung cancer in smokers(as if that were possible!) I have harbored suspicions that beta carotene should not be added to multi vitamins. Smokers should definitely avoid beta carotene in vitamin pills and problem be careful about the intake from natural sources. As for non smokers, the data is equivocal. Beta carotene does not appear to be a causative factor for or against developing cancer.
Ascorbic acid, a variant of vitamin C, appears to be a double edged sword. At high doses it can stimulate the production reactive oxygen species, particularly in the presence of free iron, the latter often being present in inflammatory conditions. Mega dosing of vitamin C is a waste of money and can damage the gut. Once tissue saturation of vitamin C is achieved there is little point in swallowing vitamin C tablets because it will not pass the gut wall. Smokers should increase their intake of vitamin C has it has been shown to help preserve vitamin E levels. As with most antioxidants, it is generally better to consume these throughout the day because this will help maintain tissue levels through the course of the day, whereas consuming antioxidant rich foods or supplements at one time of the day will lead to depletion until topping up occurs at the next meal.
The flip side of megadosing for vitamin C is recent studies which found that intravenous injections of vitamin C may have therapeutic use in treating some cancers.
The below study can be downloaded at this site.
Reading
Article
The role of antioxidant supplement in immune system, neoplastic,
and neurodegenerative disorders: a point of view for an assessment
of the risk/benefit profile
Authors
Daria Brambilla1, Cesare Mancuso2, Mariagrazia Rita Scuderi1, Paolo Bosco3,
Giuseppina Cantarella1, Laurence Lempereur1, Giulia Di BenedettoLL0000001,
Salvatore Pezzino1 and Renato Bernardini*1
Journal
Nutrition Journal 2008, 7:29 doi:10.1186/1475-2891-7-29
Location
Life\Nutrition\
Date obtained
2/11/2008
Date Read
7/11/2008
Date to Review
Web Page
http://www.nutritionj.com/content/7/1/29
Keywords
Printed
Notes
Abstract
This review will discuss some issues related to the risk/benefit profile of the use of dietary antioxidants. Thus, recent progress regarding the potential benefit of dietary antioxidants in the treatment of chronic diseases with a special focus on immune system and neurodegenerative disorders will be discussed here. It is well established that reactive oxygen species (ROS) play an important role in the etiology of numerous diseases, such as atherosclerosis, diabetes and cancer. Among the physiological defense system of the cell, the relevance of antioxidant molecules, such as glutathione and vitamins is quite well established. Recently, the interest of researchers has, for example, been conveyed on antioxidant enzyme systems, such as the heme oxygenase/biliverdin reductase system, which appears modulated by dietary antioxidant molecules, including polyphenols and beta-carotene. These systems possibly counteract oxidative damage very efficiently and finally modulate the activity of oxidative phenomena occurring, for instance, during pathophysiological processes. Although evidence shows that antioxidant treatment results in cytoprotection, the potential clinical benefit deriving from both nutritional and supplemental antioxidants is still under wide debate. In this line, the inappropriate assumption of some lipophylic vitamins has been associated with increased incidence of cancer rather than with beneficial effects.
Friday, October 31, 2008
With Reckless Abandon We Contaminate Our Home
Yet another study has emerged indicating that reckless disregard towards the consequences of environmental pollution is a health hazard for all of us. Libertarians and their ilk may argue that property rights will afford protection against pollution but this is unmitigated piffle. Pollution does not recognise boundaries or property rights and it can take decades for the full consequences of a pollutant to become apparent. Methylmercury is an excellent example of that.
Wines and Heavy Metals
For years we have been advised that a glass or two of wine is good for us and then this pops up. The basic message is: some European wines have such extraordinarily levels of heavy metals that even a single glass could be bad for our health.
There is an important nutritional lesson here and it is this: we're ignorant. For all the research that goes on we are a very long way of knowing what exactly constitutes good living. The research must proceed but please be very careful with health reporting. It is so very difficult to draw conclusions from a group of studies let alone a single study. Whatever you do with regard to your health always stick to the essentials. Experiment with diet and supplements, where possible do this in the context of regular blood tests so as to determine the effects. Remember, studies are statistical, the results of a particular study may be completely you irrelevant for someone living your life and with your physiology.
At the end of the day, all of us have to find out what works for us healthwise.
There is an important nutritional lesson here and it is this: we're ignorant. For all the research that goes on we are a very long way of knowing what exactly constitutes good living. The research must proceed but please be very careful with health reporting. It is so very difficult to draw conclusions from a group of studies let alone a single study. Whatever you do with regard to your health always stick to the essentials. Experiment with diet and supplements, where possible do this in the context of regular blood tests so as to determine the effects. Remember, studies are statistical, the results of a particular study may be completely you irrelevant for someone living your life and with your physiology.
At the end of the day, all of us have to find out what works for us healthwise.
Saturday, October 25, 2008
SAM-e can be Dangerous
SAM-e is being widely promoted as a "natural antidepressant". Quite by accident I recently stumbled upon some data which indicated that sustained use of SAM-e is potentially very dangerous.
SAM-e is S-adenosylmethionine. Part of its known actions is to act as a methyl donor. If you are using SAM-e you must make sure your vitamin B levels are adequate. The use of SAM-e has been associated with hyperhomocysteinemia, excess SAM-e is associated with Parkinson's Disease like disorders, excess methyl donation is a risk factor for some cancers, and the hyperhomocysteinemia that can arise from unwise use of SAM-e can induce atherosclerosis. It has also been found that in the brains of schizophrenic patients there is an over expression of SAM-e. Excessive SAM-e also induces oxidative stress and lipid peroxidation.
If you are taking S-adenosylmethionine be absolutely certain you have a very good intake of the B vitamin group, particularly folate, and you have a good antioxidant intake as well.
NEVER take SAM-e in conjunction with any antidepressants, "natural" or otherwise. It is probably advisable that before taking SAM-e you should have your homocysteine levels checked. If these levels are high then do not take it and immediately boost your intake of B vitamins and folate.
If you are using SAM-e for depression you might want to consider an "unnatural antidepressant" prescribed by your doctor. Antidepressant drugs are amongst the most widely prescribed drugs and have been subject to extensive trials and analysis. They have an excellent safety profile but it can take quite some experimentation to find the antidepressant that works for you. As recent studies have indicated the efficacy of antidepressants appears contingent on the induction of neurogenesis. This is probably a downstream effect from antidepressant use. At present I am taking an antidepressant. No, I'm not depressed, I just prefer the occasional dosing of an antidepressant because the one I am using has a number of favourable qualities.
Ideally if you are suffering from depression you should first try strategies that do not require taking anything. Check your diet, get some regular exercise, spend time with positive people, stabilise your sleep patterns if need be, get out in the sun occasionally(yes, sunshine, probably via circadian regulation and vitamin D, can give a slight boost to serotonin levels), and find ways to reduce your stress levels.
A brief overview of SAM-e is available at Wikipedia.
SAM-e is S-adenosylmethionine. Part of its known actions is to act as a methyl donor. If you are using SAM-e you must make sure your vitamin B levels are adequate. The use of SAM-e has been associated with hyperhomocysteinemia, excess SAM-e is associated with Parkinson's Disease like disorders, excess methyl donation is a risk factor for some cancers, and the hyperhomocysteinemia that can arise from unwise use of SAM-e can induce atherosclerosis. It has also been found that in the brains of schizophrenic patients there is an over expression of SAM-e. Excessive SAM-e also induces oxidative stress and lipid peroxidation.
If you are taking S-adenosylmethionine be absolutely certain you have a very good intake of the B vitamin group, particularly folate, and you have a good antioxidant intake as well.
NEVER take SAM-e in conjunction with any antidepressants, "natural" or otherwise. It is probably advisable that before taking SAM-e you should have your homocysteine levels checked. If these levels are high then do not take it and immediately boost your intake of B vitamins and folate.
If you are using SAM-e for depression you might want to consider an "unnatural antidepressant" prescribed by your doctor. Antidepressant drugs are amongst the most widely prescribed drugs and have been subject to extensive trials and analysis. They have an excellent safety profile but it can take quite some experimentation to find the antidepressant that works for you. As recent studies have indicated the efficacy of antidepressants appears contingent on the induction of neurogenesis. This is probably a downstream effect from antidepressant use. At present I am taking an antidepressant. No, I'm not depressed, I just prefer the occasional dosing of an antidepressant because the one I am using has a number of favourable qualities.
Ideally if you are suffering from depression you should first try strategies that do not require taking anything. Check your diet, get some regular exercise, spend time with positive people, stabilise your sleep patterns if need be, get out in the sun occasionally(yes, sunshine, probably via circadian regulation and vitamin D, can give a slight boost to serotonin levels), and find ways to reduce your stress levels.
A brief overview of SAM-e is available at Wikipedia.
Brain Aging in Relation to Genes, Diet, and Behavior
Over recent years there has been tremendous progress in our understanding of brain aging and neurodegeneration. Whereas in times past it was presumed that little could be done to forestall the onset of age associated cognitive impairment it is now obvious that there is a welter of strategies we can utilise to markedly slow down the rate of age associated cognitive impairment.
This review article from Mark P. Mattson et. al. is a good starting point for enhancing your understanding of brain aging and the strategies that can help in slowing that trend. Some even claim that one can completely forestall brain aging. I remain very cynical of that possibility but hey it is worth a try so give it a go!
In brief, the following strategies are advisable:
The abstract:
Mattson, Mark P., Sic L. Chan, and Wenzhen Duan. Modification of Brain Aging and Neurodegenerative Disorders by Genes, Diet, and Behavior. Physiol. Rev. 82: 637-672, 2002; 10.1152/physrev.00004.2002.
Multiple molecular, cellular, structural, and functional changes occur in the brain during aging. Neural cells may respond to these changes adaptively, or they may succumb to neurodegenerative cascades that result in disorders such as Alzheimer's and Parkinson's diseases. Multiple mechanisms are employed to maintain the integrity of nerve cell circuits and to facilitate responses to environmental demands and promote recovery of function after injury. The mechanisms include production of neurotrophic factors and cytokines, expression of various cell survival-promoting proteins (e.g., protein chaperones, antioxidant enzymes, Bcl-2 and inhibitor of apoptosis proteins), preservation of genomic integrity by telomerase and DNA repair proteins, and mobilization of neural stem cells to replace damaged neurons and glia. The aging process challenges such neuroprotective and neurorestorative mechanisms. Genetic and environmental factors superimposed upon the aging process can determine whether brain aging is successful or unsuccessful. Mutations in genes that cause inherited forms of Alzheimer's disease (amyloid precursor protein and presenilins), Parkinson's disease (
-synuclein and Parkin), and trinucleotide repeat disorders (huntingtin, androgen receptor, ataxin, and others) overwhelm endogenous neuroprotective mechanisms; other genes, such as those encoding apolipoprotein E4, have more subtle effects on brain aging. On the other hand, neuroprotective mechanisms can be bolstered by dietary (caloric restriction and folate and antioxidant supplementation) and behavioral (intellectual and physical activities) modifications. At the cellular and molecular levels, successful brain aging can be facilitated by activating a hormesis response in which neurons increase production of neurotrophic factors and stress proteins. Neural stem cells that reside in the adult brain are also responsive to environmental demands and appear capable of replacing lost or dysfunctional neurons and glial cells, perhaps even in the aging brain. The recent application of modern methods of molecular and cellular biology to the problem of brain aging is revealing a remarkable capacity within brain cells for adaptation to aging and resistance to disease.
This review article from Mark P. Mattson et. al. is a good starting point for enhancing your understanding of brain aging and the strategies that can help in slowing that trend. Some even claim that one can completely forestall brain aging. I remain very cynical of that possibility but hey it is worth a try so give it a go!
In brief, the following strategies are advisable:
- Regular light aerobic exercise.
- Moderate fasting a couple of times a week appears to be beneficial. Caloric Restriction, however, is ill advised as there is some suggestion that over the long term it can damage the brain.
- A good diet, obviously.
- Avoiding saturated fats and trans fats. Do not eliminate saturated fat, just reduce it.
- Maintaining an appropriate balance of omega 3 to omega 6 fats.
- Regular sleeping patterns.
- Avoiding excessive stress.
- Treat depression quickly. Numerous studies now indicate that depression damages the brain and the body. In fact sustained major depression is a significant risk factor for Alzheimers and a minor risk factor for heart disease.
- Avoid knocks to the head. Even mild brain injury can pave the way for latter dementia.
The abstract:
Mattson, Mark P., Sic L. Chan, and Wenzhen Duan. Modification of Brain Aging and Neurodegenerative Disorders by Genes, Diet, and Behavior. Physiol. Rev. 82: 637-672, 2002; 10.1152/physrev.00004.2002.
Multiple molecular, cellular, structural, and functional changes occur in the brain during aging. Neural cells may respond to these changes adaptively, or they may succumb to neurodegenerative cascades that result in disorders such as Alzheimer's and Parkinson's diseases. Multiple mechanisms are employed to maintain the integrity of nerve cell circuits and to facilitate responses to environmental demands and promote recovery of function after injury. The mechanisms include production of neurotrophic factors and cytokines, expression of various cell survival-promoting proteins (e.g., protein chaperones, antioxidant enzymes, Bcl-2 and inhibitor of apoptosis proteins), preservation of genomic integrity by telomerase and DNA repair proteins, and mobilization of neural stem cells to replace damaged neurons and glia. The aging process challenges such neuroprotective and neurorestorative mechanisms. Genetic and environmental factors superimposed upon the aging process can determine whether brain aging is successful or unsuccessful. Mutations in genes that cause inherited forms of Alzheimer's disease (amyloid precursor protein and presenilins), Parkinson's disease (-synuclein and Parkin), and trinucleotide repeat disorders (huntingtin, androgen receptor, ataxin, and others) overwhelm endogenous neuroprotective mechanisms; other genes, such as those encoding apolipoprotein E4, have more subtle effects on brain aging. On the other hand, neuroprotective mechanisms can be bolstered by dietary (caloric restriction and folate and antioxidant supplementation) and behavioral (intellectual and physical activities) modifications. At the cellular and molecular levels, successful brain aging can be facilitated by activating a hormesis response in which neurons increase production of neurotrophic factors and stress proteins. Neural stem cells that reside in the adult brain are also responsive to environmental demands and appear capable of replacing lost or dysfunctional neurons and glial cells, perhaps even in the aging brain. The recent application of modern methods of molecular and cellular biology to the problem of brain aging is revealing a remarkable capacity within brain cells for adaptation to aging and resistance to disease.
Placebo Power
Henry Beecher would have been pleased with these findings. He pioneered the concept of the placebo effect. A surgeon in World War 2, he found that simply giving wounded soldiers a sugar pill alleviated their pain. Fascinated by this after World War 2 he began research into the Placebo Effect.
Sadly the Placebo Effect is often perceived as a statistical artefact rather than a real phenomenon. However it can be very powerful. Even classical conditioning has been shown to induce altered immune responses in humans and rats. In fact in humans one can induce immunosuppression through behavioral conditioning. Now before you start thinking something spooky is going on here, you should read this article which indicates that there is a physical basis for this phenomenon.
There needs to be greater attention to the potential of the Placebo Effect in clinical practice. As this news item indicates, many doctors are not adverse to using the Placebo Effect in their daily practice.
For an introduction to the work of Henry Beecher, read this Wikipedia entry.
Sadly the Placebo Effect is often perceived as a statistical artefact rather than a real phenomenon. However it can be very powerful. Even classical conditioning has been shown to induce altered immune responses in humans and rats. In fact in humans one can induce immunosuppression through behavioral conditioning. Now before you start thinking something spooky is going on here, you should read this article which indicates that there is a physical basis for this phenomenon.
There needs to be greater attention to the potential of the Placebo Effect in clinical practice. As this news item indicates, many doctors are not adverse to using the Placebo Effect in their daily practice.
For an introduction to the work of Henry Beecher, read this Wikipedia entry.
Friday, October 24, 2008
Eat Smart, Be Smart
They like to say that we cannot improve our intelligence. Recent studies have contradicted this as has my personal experience. There are a great many things we can do to improve our intelligence but to achieve maximum benefit requires careful management and a holistic approach to health. By "holistic" I do not mean that New Age crap or the continual popping of pills, but rather an integrated approach where we address many aspects of our lives. This includes:
DHA: an important omega 3 fat that is a substrate for NPD1, a neuroprotective compound that prevents apoptosis(programmed cell death).
Choline: an important component in cell walls and also a substrate for acetylcholine, the "memory neurotransmitter".
A news item on the study can be read here.
FASEB, July 2008
Abstract:
This study examined the effects on cognitive behaviors of giving normal adult gerbils three compounds, normally in the circulation, which interact to increase brain phosphatides, synaptic proteins, dendritic spines, and neurotransmitter release. Animals received supplemental uridine (as its monophosphate, UMP; 0.5%) and choline (0.1%) via the diet, and docosahexaenoic acid (DHA; 300 mg/kg/day) by gavage, for 4 wk, and then throughout the subsequent period of behavioral training and testing. As shown previously, giving all three compounds caused highly significant (P<0.001)>
- Being happy. If you are lacking happiness then this is the first challenge you must address.
- Sound sleep. There used to be the boast of how little sleep one could get by on. Great, welcome to future dementia.
- Aerobic fitness. Absolutely essential.
- Don't just exercise your brain, push it. Make it work. Read material that you find challenging, that makes you think, that challenges your preconceptions. One of my favourite quotes is:*Gelett Burgess: "If in the last few years you haven't discarded a major opinion or acquired a new one, check your pulse. You may be dead."
- Remember that exercising the brain is not just about conceptual work, bodily exercises that require co-ordination and timing can also be very important. This is further highlighted by recent research indicating that simple physical training in co-ordination appears to be beneficial for some children with ADHD. This appears to be related to the cerebellum(little brain). This part of the CNS has been neglected for too long.
- Eat well.
DHA: an important omega 3 fat that is a substrate for NPD1, a neuroprotective compound that prevents apoptosis(programmed cell death).
Choline: an important component in cell walls and also a substrate for acetylcholine, the "memory neurotransmitter".
A news item on the study can be read here.
FASEB, July 2008
Dietary uridine enhances the improvement in learning and memory produced by administering DHA to gerbils
Abstract:
This study examined the effects on cognitive behaviors of giving normal adult gerbils three compounds, normally in the circulation, which interact to increase brain phosphatides, synaptic proteins, dendritic spines, and neurotransmitter release. Animals received supplemental uridine (as its monophosphate, UMP; 0.5%) and choline (0.1%) via the diet, and docosahexaenoic acid (DHA; 300 mg/kg/day) by gavage, for 4 wk, and then throughout the subsequent period of behavioral training and testing. As shown previously, giving all three compounds caused highly significant (P<0.001)>
Thursday, October 23, 2008
The Mediterranean Diet
You may have heard about the Mediterranean Diet and its implications for health. This meta-analysis confirms previous findings, including reductions in mortality from cardiovacular disease(9%), cancer(6%), Parkinson's Disease, and Alzheimers(13%).
In short, the diet focuses on high intakes of legumes vegetables, high cereals, relative absence of red and processed meats, a high ratio for Monunsaturated vs. Saturated Fat, low milk and dairy products.
I have concerns about a high cereal diet and suggest that this is not a necessary component in relation to the health benefits derived from the Mediterranean diet. Cereals tend to contain high levels of omega 6 and this may create an unbalance in relation to omega 3 levels. Additionally, cereals are often high in carbohydrates, thus potentially leading to excess caloric intake.
However I do agree that in general we consume too much processed and red meat. As recent studies have indicated simply reducing protein intake, as opposed to adopting a torturous caloric restriction regime, can confer substantial benefits. We need to be cautious here, in reducing protein intake we may also be depriving ourselves of some essential amino acids.
An important component of the Mediterranean diet is the large amounts of olive oil used. Monounsaturated fats tend to be ignored these days, in my view there is too much emphasis on omega 3's and I have some concerns about high levels of omega 3's in the diet. After all, eskimos may be relatively free of conditions associated with an imbalance of the omega 3 and omega 6 fats, but they also tend to suffer from cerebral hemorrhages in their 60's and 70's. This propensity to bleeding first came to my attention is a wonderful text on lipids: The Fats of Life by Caroline M Pond. You can preview this text at this site. Thanks Google! The Australian Cardiologist, Ross Walker, also makes reference to this in his text The Cell Factor. I highly recommend this text, it contains abundant useful advice and for anyone with a cardiovascular condition it should be recommended reading.
Another reason I am interested in the role of monounsaturated fats is a study I read wherein they induced a cortical lesion in animals and then gave a massive intravenous infusion of monounsaturated fats. The results were remarkable, a huge reduction in lesion size. Unfortunately I cannot find it in my archives. It seems my memory is still better than my damned database.
Adherence to Mediterranean diet and health status: meta-analysis
Updated information and services can be found at:
http://bmj.com/cgi/content/full/337/sep11_2/a1344
ABSTRACT
Objective To systematically review all the prospective cohort studies that have analysed the relation between adherence to a Mediterranean diet, mortality, and incidence of chronic diseases in a primary prevention setting.
Design
Meta-analysis of prospective cohort studies. Data sources English and non-English publications in PubMed, Embase, Web of Science, and the Cochrane Central Register of Controlled Trials from 1966 to 30 June 2008.
Studies reviewed Studies that analysed prospectively the association between adherence to a Mediterranean diet, mortality, and incidence of diseases; 12 studies, with a total of 1 574 299 subjects followed for a time ranging from three to 18 years were included.
Results
The cumulative analysis among eight cohorts (514 816 subjects and 33 576 deaths) evaluating overall mortality in relation to adherence to a Mediterranean diet showed that a two point increase in the adherence score was significantly associated with a reduced risk of
mortality (pooled relative risk 0.91, 95% confidence interval 0.89 to 0.94). Likewise, the analyses showed a beneficial role for greater adherence to a Mediterranean
diet on cardiovascular mortality (pooled relative risk 0.91, 0.87 to 0.95), incidence of or mortality from cancer (0.94,0.92 to 0.96), and incidence of Parkinson’s disease and
Alzheimer’s disease (0.87, 0.80 to 0.96).
Conclusions
Greater adherence to a Mediterranean diet is associated with a significant improvement in health status, as seen by a significant reduction in overall mortality (9%), mortality from cardiovascular diseases (9%), incidence of or mortality from cancer (6%), and
incidence of Parkinson’s disease and Alzheimer’s disease (13%). These results seem to be clinically relevant for public health, in particular for encouraging a Mediterranean-like dietary pattern for primary prevention of major chronic diseases.
In short, the diet focuses on high intakes of legumes vegetables, high cereals, relative absence of red and processed meats, a high ratio for Monunsaturated vs. Saturated Fat, low milk and dairy products.
I have concerns about a high cereal diet and suggest that this is not a necessary component in relation to the health benefits derived from the Mediterranean diet. Cereals tend to contain high levels of omega 6 and this may create an unbalance in relation to omega 3 levels. Additionally, cereals are often high in carbohydrates, thus potentially leading to excess caloric intake.
However I do agree that in general we consume too much processed and red meat. As recent studies have indicated simply reducing protein intake, as opposed to adopting a torturous caloric restriction regime, can confer substantial benefits. We need to be cautious here, in reducing protein intake we may also be depriving ourselves of some essential amino acids.
An important component of the Mediterranean diet is the large amounts of olive oil used. Monounsaturated fats tend to be ignored these days, in my view there is too much emphasis on omega 3's and I have some concerns about high levels of omega 3's in the diet. After all, eskimos may be relatively free of conditions associated with an imbalance of the omega 3 and omega 6 fats, but they also tend to suffer from cerebral hemorrhages in their 60's and 70's. This propensity to bleeding first came to my attention is a wonderful text on lipids: The Fats of Life by Caroline M Pond. You can preview this text at this site. Thanks Google! The Australian Cardiologist, Ross Walker, also makes reference to this in his text The Cell Factor. I highly recommend this text, it contains abundant useful advice and for anyone with a cardiovascular condition it should be recommended reading.
Another reason I am interested in the role of monounsaturated fats is a study I read wherein they induced a cortical lesion in animals and then gave a massive intravenous infusion of monounsaturated fats. The results were remarkable, a huge reduction in lesion size. Unfortunately I cannot find it in my archives. It seems my memory is still better than my damned database.
Adherence to Mediterranean diet and health status: meta-analysis
Updated information and services can be found at:
http://bmj.com/cgi/content/full/337/sep11_2/a1344
ABSTRACT
Objective To systematically review all the prospective cohort studies that have analysed the relation between adherence to a Mediterranean diet, mortality, and incidence of chronic diseases in a primary prevention setting.
Design
Meta-analysis of prospective cohort studies. Data sources English and non-English publications in PubMed, Embase, Web of Science, and the Cochrane Central Register of Controlled Trials from 1966 to 30 June 2008.
Studies reviewed Studies that analysed prospectively the association between adherence to a Mediterranean diet, mortality, and incidence of diseases; 12 studies, with a total of 1 574 299 subjects followed for a time ranging from three to 18 years were included.
Results
The cumulative analysis among eight cohorts (514 816 subjects and 33 576 deaths) evaluating overall mortality in relation to adherence to a Mediterranean diet showed that a two point increase in the adherence score was significantly associated with a reduced risk of
mortality (pooled relative risk 0.91, 95% confidence interval 0.89 to 0.94). Likewise, the analyses showed a beneficial role for greater adherence to a Mediterranean
diet on cardiovascular mortality (pooled relative risk 0.91, 0.87 to 0.95), incidence of or mortality from cancer (0.94,0.92 to 0.96), and incidence of Parkinson’s disease and
Alzheimer’s disease (0.87, 0.80 to 0.96).
Conclusions
Greater adherence to a Mediterranean diet is associated with a significant improvement in health status, as seen by a significant reduction in overall mortality (9%), mortality from cardiovascular diseases (9%), incidence of or mortality from cancer (6%), and
incidence of Parkinson’s disease and Alzheimer’s disease (13%). These results seem to be clinically relevant for public health, in particular for encouraging a Mediterranean-like dietary pattern for primary prevention of major chronic diseases.
Power Napping
Sleep deprivation is chronic in our society and this has important implications for our health. Chronic sleep deprivation typically increases the production of proinflammatory cytokines. Chronic sleep deprivation will induce increased production of cortisol and interleukin 6. Both have a number of functions in physiology.
Cortisol is a key stress hormone that is important in suppressing excessive inflammatory responses and helping us to maintain alertness. Throughout the 24 hour period both cortisol and interleukin 6, along with a host of other physiological mediators, vary in accordance with our circadian rhythms. Cortisol rises in the early hours of the morning, helping us to wake up, climbs through the morning, then starts a gradual decline through the evening and night. At basal physiological levels it plays important roles.
Interleukin 6 is a perplexing cytokine, it has been associated both with inflammatory and growth processes, my guess is that its function is contingent on the expression of inflammatory mediators like tumour necrosis factor. That is, in the presence of tumour necrosis factor at elevated levels, in can promote inflammation. It is worth noting that in this study at least the levels of tumour necrosis factor were largely unaffected.
In this study the human subjects were sleep deprived for a number of days and then allowed to nap for 2 hours. The effects were minor, statistically significant yes but physiologically significant? Not so sure about that. Napping does help but it cannot make up for maintaining good sleeping patterns.
The Lesson
Don't fall for the idea that you can catch up on sleep and no harm done. Sleep deprivation is a stressor and will impact your performance. Chronic sleep deprivation will do you no good at all. It will do the exact opposite. During the deepest phases of our sleep cycle growth hormone levels are elevated, and various repair processes come into play. As high cortisol is often found in depression, chronic sleep deprivation can pave the way for depression. Indeed it can be the final straw that breaks the camel's back. So if you are experiencing chronic sleep deprivation try to find ways to change that.
I take good quality sleep so seriously that I wear a sleep mask and ear plugs. This has a wonderful effect on my sleep cycle and I typically wake up wonderfully refreshed. A great change from years gone by when I would wake up feeling like death. I am a night owl who likes to stay up late, typically reading, studying, or just playing computer games. However I do make sure I get a good night's sleep and this has substantially improved my productivity and cognition.
If you're interested in learning about sleep and the importance of maintaining regular sleeping patterns I highly recommend The Promise of Sleep by William C. Dement and Christopher Vaughan. Dr. Dement commenced the Stanford Sleep Centre and is a leading authority on sleep. The text is very accessible. Here is a link to it.
You can download the full paper here.
Am J Physiol Endocrinol Metab 292: E253–E261, 2007.
Daytime napping after a night of sleep loss decreases sleepiness,improves performance, and causes beneficial changes in cortisol and interleukin-6 secretion
A. N. Vgontzas,S. Pejovic, E. Zoumakis, H. M. Lin, E. O. Bixler, M. Basta, J. Fang, A. Sarrigiannidis, and G. P. Chrousos
Daytime napping after a
night of sleep loss decreases sleepiness, improves performance, and
causes beneficial changes in cortisol and interleukin-6 secretion. Am J
Physiol Endocrinol Metab 292: E253–E261, 2007. First published August
29, 2006; doi:10.1152/ajpendo.00651.2005.—Sleep loss has been
associated with increased sleepiness, decreased performance, elevations
in inflammatory cytokines, and insulin resistance. Daytime napping has
been promoted as a countermeasure to sleep loss. To assess the effects of
a 2-h midafternoon nap following a night of sleep loss on postnap
sleepiness, performance, cortisol, and IL-6, 41 young healthy individuals
(20 men, 21 women) participated in a 7-day sleep deprivation experiment
(4 consecutive nights followed by a night of sleep loss and 2 recovery
nights). One-half of the subjects were randomly assigned to take a
midafternoon nap (1400–1600) the day following the night of total sleep
loss. Serial 24-h blood sampling, multiple sleep latency test (MSLT),
subjective levels of sleepiness, and psychomotor vigilance task (PVT)
were completed on the fourth (predeprivation) and sixth days (postdeprivation).
During the nap, subjects had a significant drop in cortisol and
IL-6 levels (P < 0.05). After the nap they experienced significantly less
sleepiness (MSLT and subjective, P < 0.05) and a smaller improvement
on the PVT (P < 0.1). At that time, they had a significant transient
increase in their cortisol levels (P < 0.05). In contrast, the levels of IL-6
tended to remain decreased for ~8 h (P < 0.1). We conclude that a 2-h
midafternoon nap improves alertness, and to a lesser degree performance,
and reverses the effects of one night of sleep loss on cortisol and IL-6.
The redistribution of cortisol secretion and the prolonged suppression of
IL-6 secretion are beneficial, as they improve alertness and performance.
Cortisol is a key stress hormone that is important in suppressing excessive inflammatory responses and helping us to maintain alertness. Throughout the 24 hour period both cortisol and interleukin 6, along with a host of other physiological mediators, vary in accordance with our circadian rhythms. Cortisol rises in the early hours of the morning, helping us to wake up, climbs through the morning, then starts a gradual decline through the evening and night. At basal physiological levels it plays important roles.
Interleukin 6 is a perplexing cytokine, it has been associated both with inflammatory and growth processes, my guess is that its function is contingent on the expression of inflammatory mediators like tumour necrosis factor. That is, in the presence of tumour necrosis factor at elevated levels, in can promote inflammation. It is worth noting that in this study at least the levels of tumour necrosis factor were largely unaffected.
In this study the human subjects were sleep deprived for a number of days and then allowed to nap for 2 hours. The effects were minor, statistically significant yes but physiologically significant? Not so sure about that. Napping does help but it cannot make up for maintaining good sleeping patterns.
The Lesson
Don't fall for the idea that you can catch up on sleep and no harm done. Sleep deprivation is a stressor and will impact your performance. Chronic sleep deprivation will do you no good at all. It will do the exact opposite. During the deepest phases of our sleep cycle growth hormone levels are elevated, and various repair processes come into play. As high cortisol is often found in depression, chronic sleep deprivation can pave the way for depression. Indeed it can be the final straw that breaks the camel's back. So if you are experiencing chronic sleep deprivation try to find ways to change that.
I take good quality sleep so seriously that I wear a sleep mask and ear plugs. This has a wonderful effect on my sleep cycle and I typically wake up wonderfully refreshed. A great change from years gone by when I would wake up feeling like death. I am a night owl who likes to stay up late, typically reading, studying, or just playing computer games. However I do make sure I get a good night's sleep and this has substantially improved my productivity and cognition.
If you're interested in learning about sleep and the importance of maintaining regular sleeping patterns I highly recommend The Promise of Sleep by William C. Dement and Christopher Vaughan. Dr. Dement commenced the Stanford Sleep Centre and is a leading authority on sleep. The text is very accessible. Here is a link to it.
You can download the full paper here.
Am J Physiol Endocrinol Metab 292: E253–E261, 2007.
Daytime napping after a night of sleep loss decreases sleepiness,improves performance, and causes beneficial changes in cortisol and interleukin-6 secretion
A. N. Vgontzas,S. Pejovic, E. Zoumakis, H. M. Lin, E. O. Bixler, M. Basta, J. Fang, A. Sarrigiannidis, and G. P. Chrousos
Daytime napping after a
night of sleep loss decreases sleepiness, improves performance, and
causes beneficial changes in cortisol and interleukin-6 secretion. Am J
Physiol Endocrinol Metab 292: E253–E261, 2007. First published August
29, 2006; doi:10.1152/ajpendo.00651.2005.—Sleep loss has been
associated with increased sleepiness, decreased performance, elevations
in inflammatory cytokines, and insulin resistance. Daytime napping has
been promoted as a countermeasure to sleep loss. To assess the effects of
a 2-h midafternoon nap following a night of sleep loss on postnap
sleepiness, performance, cortisol, and IL-6, 41 young healthy individuals
(20 men, 21 women) participated in a 7-day sleep deprivation experiment
(4 consecutive nights followed by a night of sleep loss and 2 recovery
nights). One-half of the subjects were randomly assigned to take a
midafternoon nap (1400–1600) the day following the night of total sleep
loss. Serial 24-h blood sampling, multiple sleep latency test (MSLT),
subjective levels of sleepiness, and psychomotor vigilance task (PVT)
were completed on the fourth (predeprivation) and sixth days (postdeprivation).
During the nap, subjects had a significant drop in cortisol and
IL-6 levels (P < 0.05). After the nap they experienced significantly less
sleepiness (MSLT and subjective, P < 0.05) and a smaller improvement
on the PVT (P < 0.1). At that time, they had a significant transient
increase in their cortisol levels (P < 0.05). In contrast, the levels of IL-6
tended to remain decreased for ~8 h (P < 0.1). We conclude that a 2-h
midafternoon nap improves alertness, and to a lesser degree performance,
and reverses the effects of one night of sleep loss on cortisol and IL-6.
The redistribution of cortisol secretion and the prolonged suppression of
IL-6 secretion are beneficial, as they improve alertness and performance.
Wednesday, October 22, 2008
Eat slowly, eat well, with friends and\or family
In our fast paced world eating has taken on a utilitarian aspect that is not doing us any good at all. We read the labels for nutrients, we pop pills for health, we eat on the run, we avoid unhealthy foods, we have turned eating into a chore when it should be a pleasure.
Even supermarkets are now selling various supplements, foods are fortified with this and that, purportedly claiming superior health from eating these fortified foods. The evidence for this is scant. What epidemiological studies show is that you don't need a "scientifically" determined eating plan but rather observing some simple rules for eating healthily.
The French Paradox remains unresolved. Basically it goes like this: the French eat a great many unhealthy foods yet have markedly lower rates of the types of diseases that pervade many Western countries. The French enjoy their food, eat as a social event not as an intrusion on a busy life. They take time to enjoy their food, eat much more slowly than us, and enjoy their meals.
Now consider how many of us eat: we agonise of the right balance of foods to optimise health, we eat lunch quickly so that we have more time to enjoy our lunch break before going back to the grind, we get home from work and are so tired we slap dash something together and gulp it down while watching TV or on the internet instead of using meal time as a chance to socialise and unwind.
This latest study from the BMJ highlights a problem with our eating style. It found that eating quickly and until we are full is a risk factor for obesity. No surprises there. The feeling of being full arises when food reaches the stomach, hormones are released which signal that we have had enough to eat. However if we eat quickly the hormonal message doesn't begin to function until we have over eating. This is because it takes time for food to reach the stomach. The other problem with eating quickly is that we tend to insufficiently chew our food. This prevents nutrient absorption.
We need to change our eating habits. We need to return to the habits of enjoying eating rather than treating it as a scientific exercise. We need to eat with others, take our time, enjoy our meals, and stop obsessing about food and nutrients.
Even supermarkets are now selling various supplements, foods are fortified with this and that, purportedly claiming superior health from eating these fortified foods. The evidence for this is scant. What epidemiological studies show is that you don't need a "scientifically" determined eating plan but rather observing some simple rules for eating healthily.
The French Paradox remains unresolved. Basically it goes like this: the French eat a great many unhealthy foods yet have markedly lower rates of the types of diseases that pervade many Western countries. The French enjoy their food, eat as a social event not as an intrusion on a busy life. They take time to enjoy their food, eat much more slowly than us, and enjoy their meals.
Now consider how many of us eat: we agonise of the right balance of foods to optimise health, we eat lunch quickly so that we have more time to enjoy our lunch break before going back to the grind, we get home from work and are so tired we slap dash something together and gulp it down while watching TV or on the internet instead of using meal time as a chance to socialise and unwind.
This latest study from the BMJ highlights a problem with our eating style. It found that eating quickly and until we are full is a risk factor for obesity. No surprises there. The feeling of being full arises when food reaches the stomach, hormones are released which signal that we have had enough to eat. However if we eat quickly the hormonal message doesn't begin to function until we have over eating. This is because it takes time for food to reach the stomach. The other problem with eating quickly is that we tend to insufficiently chew our food. This prevents nutrient absorption.
We need to change our eating habits. We need to return to the habits of enjoying eating rather than treating it as a scientific exercise. We need to eat with others, take our time, enjoy our meals, and stop obsessing about food and nutrients.
Tuesday, October 21, 2008
Cerebral mitochondrial metabolism in early Parkinson's Disease
Surprising results, not sure what to make of this but it raises serious questions about mitochondrial abnormalities being the driving force in PD. However, note the last paragraph, too tentative at this point. In fact they found the opposite of what was expected. However, particularly given the sensitivity of dopaminergic neurons to oxidative stress, the increased oxygen utilisation may be the problem as it will drive oxidation events.
Article:
Cerebral mitochondrial metabolism in early
Parkinson’s disease
Authors:
William J Powers, Tom O Videen, Joanne Markham, Kevin J Black, Nima Golchin
and JoeL S Perlmutter
Journal:
Journal of Cerebral Blood Flow & Metabolism (2008) 28, 1754–1760
& 2008 ISCBFM
Location: Neuroscience\NI\Title
Date obtained: 1/10/2008
Date Read: 21/10/2008
Date to Review:
Web Page: www.jcbfm.com
Keywords:
Printed:
Notes:
Abstract
Abnormal cerebral energy metabolism owing to dysfunction of mitochondrial electron transport has been implicated in the pathogenesis of Parkinson’s disease (PD). However, in vivo data of mitochondrial dysfunction have been inconsistent. We directly investigated mitochondrial oxidative metabolism in vivo in 12 patients with early, never-medicated PD and 12 age-matched normal controls by combined measurements of the cerebral metabolic rate of oxygen (CMRO2) and the cerebral metabolic rate of glucose (CMRglc) with positron emission tomography. The primary analysis showed a statistically significant 24% increase in bihemispheric CMRO2 and no change in CMRO2/CMRglc. These findings are inconsistent with a defect in mitochondrial oxidative phosphorylation owing to reduced activity of the mitochondrial electron transport system (ETS). Because PD symptoms were already manifest, deficient energy production owing to a reduced activity of the mitochondrial ETS cannot be a primary mechanism of neuronal death in early PD. Alternatively, this general increase in CMRO2 could be due not to an increased metabolic demand but to an uncoupling of ATP production from oxidation in the terminal stage of oxidative phosphorylation. Whether this is the case in early PD and whether it is important in the pathogenesis of PD will require further study.
--
Although PD is characterized neuropathologically by alpha-synuclein-immunopositive Lewy bodies in the substantia nigra and other brainstem structures, there is an increasing recognition that PD is a diffuse brain disease involving both cortical and subcortical structures (Braak et al, 2003).
--
If a defect in mitochondrial electron transport is important in the pathogenesis of PD, it will be present early in the course of the disease and before the possibly confounding effects of drug therapy.
--
Cerebral Mitochondrial Metabolism
The primary analysis showed a statistically significant 24% increase in bihemispheric CMRO2 in PD (P = 0.037) (Table 1). This increase is the opposite direction expected for defects in mitochondrial electron transport. Bihemispheric CMRglc was increased by 15% and CMRO2/CMRglc was increased by 10%. Both of these changes are also in the opposite direction expected with defects in mitochondrial electron transport. Examination of the confidence intervals for the differences between the two groups for these latter two measurements shows that there is less than a 6% chance that CMRglc is lower in PD by any amount and only a 10% chance that CMRglc/CMRO2 is reduced by 10% or more.
Similar results, although with more measurement imprecision as expected, were found in the substantia nigra. Examination of the confidence intervals for the differences between the two groups shows that there is less than a 20% chance that substantia nigra CMRO2 in PD is lower by more than 10%, that CMRglc is lower by more than 16%, and that there is only a 10% chance that CMRglc/CMRO2 is reduced by any amount.
Measurements from the putamen and globus pallidus also showed increases in regional CMRO2 and CMRglc (Table 2). Analysis of regional/bihemispheric ratios showed no difference between controls and participants with PD indicating that the increases in regional metabolism were primarily a reflection of overall bihemispheric changes There were no differences in CMRO2 or CMRglc between the structures ipsilateral and contralateral to the side of the body with the greatest signs (data not shown).
--
Discussion
Increased CMRO2 with a normal CMRO2/CMRglc is inconsistent with a defect in mitochondrial oxidative phosphorylation owing to reduced activity of the mitochondrial ETS (Brierley et al, 1977; Frackowiak et al, 1988). Although a finding of normal CMRO2 in PD would not exclude the possibility of dysfunction of mitochondrial ETS because complex I, III, and IV activity can be substantially reduced before there is a reduction in CMRO2, dysfunction of the ETS cannot be the explanation for increased CMRO2 in PD (Davey et al, 1998). Because PD symptoms were already manifest in these 12 patients, we can exclude deficient energy production owing to a reduced activity of the mitochondrial ETS as a pathogenic mechanism of their disease. Thus, although defects in mitochondrial ETS may be present in some patients with PD, the absence of such defects in these 12 patients with early PD indicates that they cannot be esLL000000sential to the pathogenesis of neuronal death in early PD.
--
Previous studies of CMRglc in PD have yielded mixed results. In five studies of global CMRglc, four have reported reductions of approximately 20% and one reported no significant difference compared with age-matched controls (Kuhl et al, 1984; Leenders et al, 1985; Eidelberg et al, 1993, 1994; Piert et al, 1996). In one of these studies, reductions in global CMRglc were seen only after L-DOPA was administered, suggesting that the reduction in metabolism may be at least, in part, because of medication effects (Piert et al, 1996). Berding et al have suggested that hypometabolism parallels disease duration (Piert et al, 1996). Thus, these reported changes in CMRglc likely reflect a consequence of the PD process. We deliberately chose to study patients with very early disease to try to determine if there was metabolic dysfunction that caused PD. The mean disease duration of 22 months in our study was substantially shorter than in these previous studies where it ranged from 4 to 15 years. Our analysis using absolute and relative measurements showing a trend toward increased global CMRglc in very early PD supports the theory that the reported reductions in metabolism are a consequence, not a cause, of the disease.
--
Nevertheless, loss of inhibitory dopaminergic input seems an unlikely explanation for the general increase in hemispheric CMRO2 that we measured. Alternatively, this general increase in CMRO2 could be due not to an increased metabolic demand but to an uncoupling of ATP production from oxidation in the terminal stage of oxidative phosphorylation. Uncoupling (dysfunction of Complex V ATP synthase) produces an increase in both CMRO2 and CMRglc similar to what we observed (Patel and Brewer, 2003; Tretter and Adam-Vizi, 2007). Whether uncoupling of oxidative phosphorylation occurs in early PD and whether it is important in the pathogenesis of PD will require further study.
Inflammation, Cancer, Targets of Ginseng
A word of warning about using Ginseng:
If you are diabetic it is ill advised. Ginseng has a remarkable affect on the adrenal glands and this may impact on sugar regulation. Always consult your doctor before using Ginseng.
Ginseng is known to interfere with the actions of various pharmaceutical drugs.
Ginseng should not be used on a continual basis, it can induce adrenal exhaustion.
Article: Inflammation, Cancer, and Targets of Ginseng
Image:
Authors: Lorne J. Hofseth and Michael J. Wargovich
Journal: J. Nutr. 137: 183S–185S, 2007.
Location: Life\Nutrition\Title
Date obtained: 18/10/2008
Date Read: 21/10/2008
Date to Review:
Web Page:
Keywords:
Printed:
Notes:
Abstract
Chronic inflammation is associated with a high cancer risk. At the molecular level, free radicals and aldehydes, produced during chronic inflammation, can induce deleterious gene mutation and posttranslational modifications of key cancerrelated proteins. Other products of inflammation, including cytokines, growth factors, and transcription factors such as nuclear factor kB, control the expression of cancer genes (e.g., suppressor genes and oncogenes) and key inflammatory enzymes such as inducible nitric oxide synthase and cyclooxygenase-2. These enzymes in turn directly influence reactive oxygen species and eicosanoid levels. The procancerous outcome of chronic inflammation is increased DNA damage, increased DNA synthesis, cellular proliferation, disruption of DNA repair pathways and cellular milieu, inhibition of apoptosis, and promotion of angiogenesis and invasion. Chronic inflammation is also associated with immunosuppression, which is a risk factor for cancer. Current treatment strategies for reactive species overload diseases are frequently aimed at treating or preventing the cause of inflammation. Although these strategies have led to some progress in combating reactive species overload diseases and associated cancers, exposure often occurs again after eradication, treatment to eradicate the cause fails, or the treatment has long-term side effects. Therefore, the identification of molecules and pathways involved in chronic inflammation and cancer is critical to the design of agents that may help in preventing the progression of reactive species overload disease and cancer associated with disease progression. Here, we use ginseng as an example of an antiinflammatory molecule that targets many of the key players in the inflammation-to-cancer sequence. J. Nutr. 137: 183S–185S, 2007.
TABLE 1 Key players in the inflammation-to-cancer sequence1
The inflammatory player: Examples of mechanisms toward carcinogenesis
RONS, COX, and NOS Damage DNA, modify cancer protein, alter proliferation and
apoptosis (depending on concentration, microenvironment, and genetic background
of target cells), inactivate tumor suppressor pathways (e.g., pRb and p53).
NF-kB Activate proliferation and inhibit apoptosis by activating modulators of these
event: cytokines (e.g., TNF-a), growth factors, survival genes (e.g., Bcl-XL),
angiogenic factors (e.g., VEGF), inflammatory genes (e.g., COX and NOS). Recent
high profile studies indicate this molecule is a key molecular node in the
inflammation-to-cancer sequence (2).
TLRs Activate MAP kinase and NF-kB pathways.
Cytokines Activate or deactive many inflammation and cancer pathways (1). Example:
The proinflammatory cytokine, IL-6 can antagonize p53, inactivate pRb, and activate
survival genes (Bcl-2 and Bcl-XL); The antiinflammatory cytokine, IL-10, can inhibit
proliferation and ras signaling.
Growth factors Transforming growth factor-b, at high concentrations, activates
p21/p27-mediated growth arrest and smad- and p53-mediated apoptosis.
MMPs MMP-2 promotes proliferation by activation of the discoidin domain tyrosine
kinase receptor 2. MMPs also are immunomodulators and stimulate angiogenesis,
inhibit cell adhesion, and inhibit apoptosis.
PPARs PPAR-g ligands are mostly protective to the inflammation- to-cancer sequence.
They inhibit iNOS, COX-2, NF-kB, MMPs, and E2Fs; they activate p53, p27, and p21.
Kinase pathways p38 stimulates proliferation and inhibits apoptosis. An inhibitor of
MAP kinase signaling (CNI-1493) has shown promise in ameliorating Crohn disease
in humans (3).
p53 and pRb pathways Both pathways are inactivated in reactive species overload
diseases (4,5).
Studies indicate that ginseng has potential as a chemopreventive agent or adjuvant treatment. Some of the cancers shown to decrease significantly with ginseng use include cancersof the pharynx, stomach, liver, pancreas, and colon (22,23). Mechanisms include inhibition of DNA damage (24), induction of apoptosis (25), and inhibition of cell proliferation (26). It is also becoming increasingly clear that ginseng has potent effects on the inflammatory cascade and may inhibit the inflammationto- cancer sequence.
--
Ginseng targets the inflammatory players There is evidence that ginseng has potent effects on key players in the inflammatory cascade (Fig. 1). For example, ginsan, a polysaccharide extracted from P. ginseng, showed inhibition of s, the p38 MAP kinase pathway, and NF-kB in vitro and inhibition of proinflammatory cytokines in vivo (27). The ginsenoside Rg3 was shown to inhibit phorbol ester–induced COX-2 and NF-kB induction (28). BST204, a fermented ginseng extract, can inhibit inducible NOS (iNOS) expression and subsequent nitric oxide production from lipopolysaccharidestimulated RAW264.7 murine macrophages.
--
Ginseng can also inhibit other mediators of the inflammation- to-cancer sequence, such as matrix metalloproteases and kinase pathways (31).
--
Project:
If you are diabetic it is ill advised. Ginseng has a remarkable affect on the adrenal glands and this may impact on sugar regulation. Always consult your doctor before using Ginseng.
Ginseng is known to interfere with the actions of various pharmaceutical drugs.
Ginseng should not be used on a continual basis, it can induce adrenal exhaustion.
Article: Inflammation, Cancer, and Targets of Ginseng
Image:
Authors: Lorne J. Hofseth and Michael J. Wargovich
Journal: J. Nutr. 137: 183S–185S, 2007.
Location: Life\Nutrition\Title
Date obtained: 18/10/2008
Date Read: 21/10/2008
Date to Review:
Web Page:
Keywords:
Printed:
Notes:
Abstract
Chronic inflammation is associated with a high cancer risk. At the molecular level, free radicals and aldehydes, produced during chronic inflammation, can induce deleterious gene mutation and posttranslational modifications of key cancerrelated proteins. Other products of inflammation, including cytokines, growth factors, and transcription factors such as nuclear factor kB, control the expression of cancer genes (e.g., suppressor genes and oncogenes) and key inflammatory enzymes such as inducible nitric oxide synthase and cyclooxygenase-2. These enzymes in turn directly influence reactive oxygen species and eicosanoid levels. The procancerous outcome of chronic inflammation is increased DNA damage, increased DNA synthesis, cellular proliferation, disruption of DNA repair pathways and cellular milieu, inhibition of apoptosis, and promotion of angiogenesis and invasion. Chronic inflammation is also associated with immunosuppression, which is a risk factor for cancer. Current treatment strategies for reactive species overload diseases are frequently aimed at treating or preventing the cause of inflammation. Although these strategies have led to some progress in combating reactive species overload diseases and associated cancers, exposure often occurs again after eradication, treatment to eradicate the cause fails, or the treatment has long-term side effects. Therefore, the identification of molecules and pathways involved in chronic inflammation and cancer is critical to the design of agents that may help in preventing the progression of reactive species overload disease and cancer associated with disease progression. Here, we use ginseng as an example of an antiinflammatory molecule that targets many of the key players in the inflammation-to-cancer sequence. J. Nutr. 137: 183S–185S, 2007.
TABLE 1 Key players in the inflammation-to-cancer sequence1
The inflammatory player: Examples of mechanisms toward carcinogenesis
RONS, COX, and NOS Damage DNA, modify cancer protein, alter proliferation and
apoptosis (depending on concentration, microenvironment, and genetic background
of target cells), inactivate tumor suppressor pathways (e.g., pRb and p53).
NF-kB Activate proliferation and inhibit apoptosis by activating modulators of these
event: cytokines (e.g., TNF-a), growth factors, survival genes (e.g., Bcl-XL),
angiogenic factors (e.g., VEGF), inflammatory genes (e.g., COX and NOS). Recent
high profile studies indicate this molecule is a key molecular node in the
inflammation-to-cancer sequence (2).
TLRs Activate MAP kinase and NF-kB pathways.
Cytokines Activate or deactive many inflammation and cancer pathways (1). Example:
The proinflammatory cytokine, IL-6 can antagonize p53, inactivate pRb, and activate
survival genes (Bcl-2 and Bcl-XL); The antiinflammatory cytokine, IL-10, can inhibit
proliferation and ras signaling.
Growth factors Transforming growth factor-b, at high concentrations, activates
p21/p27-mediated growth arrest and smad- and p53-mediated apoptosis.
MMPs MMP-2 promotes proliferation by activation of the discoidin domain tyrosine
kinase receptor 2. MMPs also are immunomodulators and stimulate angiogenesis,
inhibit cell adhesion, and inhibit apoptosis.
PPARs PPAR-g ligands are mostly protective to the inflammation- to-cancer sequence.
They inhibit iNOS, COX-2, NF-kB, MMPs, and E2Fs; they activate p53, p27, and p21.
Kinase pathways p38 stimulates proliferation and inhibits apoptosis. An inhibitor of
MAP kinase signaling (CNI-1493) has shown promise in ameliorating Crohn disease
in humans (3).
p53 and pRb pathways Both pathways are inactivated in reactive species overload
diseases (4,5).
Studies indicate that ginseng has potential as a chemopreventive agent or adjuvant treatment. Some of the cancers shown to decrease significantly with ginseng use include cancersof the pharynx, stomach, liver, pancreas, and colon (22,23). Mechanisms include inhibition of DNA damage (24), induction of apoptosis (25), and inhibition of cell proliferation (26). It is also becoming increasingly clear that ginseng has potent effects on the inflammatory cascade and may inhibit the inflammationto- cancer sequence.
--
Ginseng targets the inflammatory players There is evidence that ginseng has potent effects on key players in the inflammatory cascade (Fig. 1). For example, ginsan, a polysaccharide extracted from P. ginseng, showed inhibition of s, the p38 MAP kinase pathway, and NF-kB in vitro and inhibition of proinflammatory cytokines in vivo (27). The ginsenoside Rg3 was shown to inhibit phorbol ester–induced COX-2 and NF-kB induction (28). BST204, a fermented ginseng extract, can inhibit inducible NOS (iNOS) expression and subsequent nitric oxide production from lipopolysaccharidestimulated RAW264.7 murine macrophages.
--
Ginseng can also inhibit other mediators of the inflammation- to-cancer sequence, such as matrix metalloproteases and kinase pathways (31).
--
Project:
Aussies and Iodine
Some may recall the time when table salt was fortified with iodine. Today that product seems rather hard to find and perhaps it is academic because so many people shy away from salt.
In this study they found a worryingly high percentage of Aussies had low iodine. A huge 43% were found to be iodine deficient. In relation to children and pregnant women this is potentially a very serious problem. Lack of iodine in children can lead to cognitive impairments and a range of other issues, in adults it can induce goiter. Iodine is essential for proper functioning of the thyroid, a gland that plays a regulatory role in the general rate of metabolism.
Food Standards Australia has released this report.
Sources of iodine:
Iodised Salt.
Seafood products.
In Australia, iodine fortified bread should be available in September 2009.
For an overview of iodine, recommended intakes and sources of iodine read this report from Nutrition Australia.
In this study they found a worryingly high percentage of Aussies had low iodine. A huge 43% were found to be iodine deficient. In relation to children and pregnant women this is potentially a very serious problem. Lack of iodine in children can lead to cognitive impairments and a range of other issues, in adults it can induce goiter. Iodine is essential for proper functioning of the thyroid, a gland that plays a regulatory role in the general rate of metabolism.
Food Standards Australia has released this report.
Sources of iodine:
Iodised Salt.
Seafood products.
In Australia, iodine fortified bread should be available in September 2009.
For an overview of iodine, recommended intakes and sources of iodine read this report from Nutrition Australia.
Bottled Water is Bollocks
Why the trend in bottled water became so prevalent was beyond me until I heard reports about the quality of drinking water in some parts of the world. Nonetheless, in most First World Countries tap water is of sufficient quality that we should not be wasting our money on bottled water. Unless of course we want to impress our friends ...
Numerous studies on bottled water have raised serious questions about the value of the product and this latest study adds further weight to the claim that bottled water is largely a waste of money. It can be summarised as follows:
You can read the full report here.
There are another important considerations in relation to bottled water. It requires plastic bottles and you may recall all the fuss recently concerning bisphenol A, a very common component in plastic bottles, is now being found to have a wide range of potentially very unpleasant health consequences. For more information this link to an earlier post of mine might help.
If only that were all. The other issue in relation to bottled water is that the manufacturing and distribution of the this product is a coal burning exercise. Even if one is doubtful concerning Global Warming, the delivery of bottled water in plastics and by transport is terribly inefficient compared to water from the tap, especially given that there is on likely benefit drinking bottled water over tap water.
Numerous studies on bottled water have raised serious questions about the value of the product and this latest study adds further weight to the claim that bottled water is largely a waste of money. It can be summarised as follows:
- Bottled water is no guarantee that the water is contaminant free. Indeed many companies will not release their own testing results of the water you buy.
- The promotional images of bottled water are very misleading, bottled water is often municipal tap water that has been purified but still contains contaminants.
- Some bottled water even contained contaminants in excess of the safe recommended levels.
- Some bottled water was indistinguishable from tap water.
You can read the full report here.
There are another important considerations in relation to bottled water. It requires plastic bottles and you may recall all the fuss recently concerning bisphenol A, a very common component in plastic bottles, is now being found to have a wide range of potentially very unpleasant health consequences. For more information this link to an earlier post of mine might help.
If only that were all. The other issue in relation to bottled water is that the manufacturing and distribution of the this product is a coal burning exercise. Even if one is doubtful concerning Global Warming, the delivery of bottled water in plastics and by transport is terribly inefficient compared to water from the tap, especially given that there is on likely benefit drinking bottled water over tap water.
Sunday, October 19, 2008
Antioxidants, Neurodegeneration, and Cancer
Research article. Interesting but lacking depth. Good balance on the issue of antioxidant supplementation.
The study can be downloaded here.
Article:
The role of antioxidant supplement in immune system, neoplastic, and
neurodegenerative disorders: a point of view for an assessment of the
risk/benefit profile
Authors:
Daria Brambilla, Cesare Mancuso,Mariagrazia Rita Scuderi,Paolo Bosco,Giuseppina Cantarella, Laurence Lempereur, Giulia Di Benedetto, Salvatore Pezzino, Renato Bernardini,
Journal: Nutrition Journal 2008, 7:29 doi:10.1186/1475-2891-7-29
Location: Life\Nutrition\title
Date obtained: 3/10/2008
Date Read: 19/10/2008
Date to Review:
Web Page:
Printed:
Notes:
Abstract
This review will discuss some issues related to the risk/benefit profile of the use of dietary antioxidants. Thus, recent progress regarding the potential benefit of dietary antioxidants in the treatment of chronic diseases with a special focus on immune system and neurodegenerative disorders will be discussed here. It is well established that reactive oxygen species (ROS) play an important role in the etiology of numerous diseases, such as atherosclerosis, diabetes and cancer. Among the physiological defense system of the cell, the relevance of antioxidant molecules, such as glutathione and vitamins is quite well established. Recently, the interest of researchers has, for example, been conveyed on antioxidant enzyme systems, such as the heme oxygenase/biliverdin reductase system, which appears modulated by dietary antioxidant molecules, including polyphenols and beta-carotene. These systems possibly counteract oxidative damage very efficiently and finally modulate the activity of oxidative phenomena occurring, for instance, during pathophysiological processes. Although evidence shows that antioxidant treatment results in cytoprotection, the potential clinical benefit deriving from both nutritional and supplemental antioxidants is still under wide debate. In this line, the inappropriate assumption of some lipophylic vitamins has been associated with increased incidence of cancer rather than with beneficial effects.
--
However, several clinical studies demonstrated that not only malnutrition, but also the excess of certain nutrients (e.g. iron, alphatocopherol, beta-carotene, ascorbic acid) may set into motion oxidation phenomena and, therefore, cell injury [8,9]. Thus, it is of relevance that prior to considering introducing antioxidant therapy into mainstream medicine, significant advances in basic cell biology, pharmacology and clinical bioanalysis will be required.
--
Heme oxygenase is a microsomal enzyme which metabolizes heme into ferrous iron, carbon monoxide and biliverdin (BV); the latter is then reduced by BVR into bilirubin (BR), a molecule endowed with strong antioxidant and antinitrosative activities [11-14]. Interestingly, all these protective factors act in a concerted way, enhancing the antioxidant defense system of the cell. When the balance between ROS/RNS and antioxidants turns in favor of the former, oxidative/nitrosative stress occurs.
--
Extracellularly generated ROS can diffuse through anion channels into the cytoplasm; the resulting variation in the cell redox state leads to modulation of an array of transcription factors (eg. NF-kB, AP-1), protein kinases (e.g. AKT, JNK, p38), and receptor activated MAP kinases involved in apoptosis [17, 24,25,26]
--
However, not only immune cell produce ROS necessary for the microbicidal activity, but they are also sensitive to external ROS, due to their high polyunsaturated fatty acids (PUFA) content. Immune cells are atypical, as compared with other somatic cells, in that they contain high levels of antioxidant vitamins, presumably providing protection against lipid peroxidation and immunosuppression, both of which are well known risks posed by high PUFA content [38].
--
Intriguingly, the combined treatment with wheat germ and vitamin C profoundly inhibited metastasis formation in various tumor models of different origin (Lewis lung carcinoma, B16 melanoma and human colon carcinoma xenografts [HCR25]) [61].
61. Hidvégi M, Ráso E, Tömösközi-Farkas R, Paku S, Lapis K, Szende B: Effect of Avemar
and Avemar + vitamin C on tumor growth and metastasis in experimental animals.
Anticancer Res 1998, 18(4A): 2353-2358.
--
Heme oxygenase-1, the inducible isoform of HO, is a key protein in the cell stress response and its up-regulation is a common event during pro-inflammatory conditions [11,69-72]. Recent work clearly demonstrated that regulatory T cells overexpress HO-1 and release CO under pro-oxidant conditions. Carbon monoxide may inhibit the proliferation of effector T cells, thus reducing the immune response and prevent autoimmunity and/or graft reaction [73,74]. Dietary antioxidants, in particular polyphenols, has been shown to increase HO-1 expression in different in vitro systems [3,75,76] and the potential use of this natural substances to regulate immune response should be carefully addressed.
--
Other studies report that combination of vitamin A and other antioxidants, significantly increases mortality related to neoplastic diseases. [91]. According to these studies, selenium would be the only element displaying beneficial effects, as it has been shown that it reduces total cancer incidence, an apparently sex-related effect, as it is predominant among males, rather than in females [89].
--
Due to their scarce bioavailability, only a negligible amount of polyphenols reaches brain tissue and the concentrations achieved are much lower than those efficacious in vitro [3]. As far as NSAIDs, ad hoc designed clinical trials with a large number of patients, clearly demonstrated that these drugs do not have any significant effect in slowing cognitive decline in patients suffering from mild-to-moderate AD [120,121].
--
It is noteworthy to underlie that as for all drugs, antioxidants may give important side effects if not correctly used or in combination with other drugs. Vitamin A, E and â-carotene for instance, have been shown to have pro-oxidant effects at higher doses or under certain conditions [39].
--
The study can be downloaded here.
Article:
The role of antioxidant supplement in immune system, neoplastic, and
neurodegenerative disorders: a point of view for an assessment of the
risk/benefit profile
Authors:
Daria Brambilla, Cesare Mancuso,Mariagrazia Rita Scuderi,Paolo Bosco,Giuseppina Cantarella, Laurence Lempereur, Giulia Di Benedetto, Salvatore Pezzino, Renato Bernardini,
Journal: Nutrition Journal 2008, 7:29 doi:10.1186/1475-2891-7-29
Location: Life\Nutrition\title
Date obtained: 3/10/2008
Date Read: 19/10/2008
Date to Review:
Web Page:
Printed:
Notes:
Abstract
This review will discuss some issues related to the risk/benefit profile of the use of dietary antioxidants. Thus, recent progress regarding the potential benefit of dietary antioxidants in the treatment of chronic diseases with a special focus on immune system and neurodegenerative disorders will be discussed here. It is well established that reactive oxygen species (ROS) play an important role in the etiology of numerous diseases, such as atherosclerosis, diabetes and cancer. Among the physiological defense system of the cell, the relevance of antioxidant molecules, such as glutathione and vitamins is quite well established. Recently, the interest of researchers has, for example, been conveyed on antioxidant enzyme systems, such as the heme oxygenase/biliverdin reductase system, which appears modulated by dietary antioxidant molecules, including polyphenols and beta-carotene. These systems possibly counteract oxidative damage very efficiently and finally modulate the activity of oxidative phenomena occurring, for instance, during pathophysiological processes. Although evidence shows that antioxidant treatment results in cytoprotection, the potential clinical benefit deriving from both nutritional and supplemental antioxidants is still under wide debate. In this line, the inappropriate assumption of some lipophylic vitamins has been associated with increased incidence of cancer rather than with beneficial effects.
--
However, several clinical studies demonstrated that not only malnutrition, but also the excess of certain nutrients (e.g. iron, alphatocopherol, beta-carotene, ascorbic acid) may set into motion oxidation phenomena and, therefore, cell injury [8,9]. Thus, it is of relevance that prior to considering introducing antioxidant therapy into mainstream medicine, significant advances in basic cell biology, pharmacology and clinical bioanalysis will be required.
--
Heme oxygenase is a microsomal enzyme which metabolizes heme into ferrous iron, carbon monoxide and biliverdin (BV); the latter is then reduced by BVR into bilirubin (BR), a molecule endowed with strong antioxidant and antinitrosative activities [11-14]. Interestingly, all these protective factors act in a concerted way, enhancing the antioxidant defense system of the cell. When the balance between ROS/RNS and antioxidants turns in favor of the former, oxidative/nitrosative stress occurs.
--
Extracellularly generated ROS can diffuse through anion channels into the cytoplasm; the resulting variation in the cell redox state leads to modulation of an array of transcription factors (eg. NF-kB, AP-1), protein kinases (e.g. AKT, JNK, p38), and receptor activated MAP kinases involved in apoptosis [17, 24,25,26]
--
However, not only immune cell produce ROS necessary for the microbicidal activity, but they are also sensitive to external ROS, due to their high polyunsaturated fatty acids (PUFA) content. Immune cells are atypical, as compared with other somatic cells, in that they contain high levels of antioxidant vitamins, presumably providing protection against lipid peroxidation and immunosuppression, both of which are well known risks posed by high PUFA content [38].
--
Intriguingly, the combined treatment with wheat germ and vitamin C profoundly inhibited metastasis formation in various tumor models of different origin (Lewis lung carcinoma, B16 melanoma and human colon carcinoma xenografts [HCR25]) [61].
61. Hidvégi M, Ráso E, Tömösközi-Farkas R, Paku S, Lapis K, Szende B: Effect of Avemar
and Avemar + vitamin C on tumor growth and metastasis in experimental animals.
Anticancer Res 1998, 18(4A): 2353-2358.
--
Heme oxygenase-1, the inducible isoform of HO, is a key protein in the cell stress response and its up-regulation is a common event during pro-inflammatory conditions [11,69-72]. Recent work clearly demonstrated that regulatory T cells overexpress HO-1 and release CO under pro-oxidant conditions. Carbon monoxide may inhibit the proliferation of effector T cells, thus reducing the immune response and prevent autoimmunity and/or graft reaction [73,74]. Dietary antioxidants, in particular polyphenols, has been shown to increase HO-1 expression in different in vitro systems [3,75,76] and the potential use of this natural substances to regulate immune response should be carefully addressed.
--
Other studies report that combination of vitamin A and other antioxidants, significantly increases mortality related to neoplastic diseases. [91]. According to these studies, selenium would be the only element displaying beneficial effects, as it has been shown that it reduces total cancer incidence, an apparently sex-related effect, as it is predominant among males, rather than in females [89].
--
Due to their scarce bioavailability, only a negligible amount of polyphenols reaches brain tissue and the concentrations achieved are much lower than those efficacious in vitro [3]. As far as NSAIDs, ad hoc designed clinical trials with a large number of patients, clearly demonstrated that these drugs do not have any significant effect in slowing cognitive decline in patients suffering from mild-to-moderate AD [120,121].
--
It is noteworthy to underlie that as for all drugs, antioxidants may give important side effects if not correctly used or in combination with other drugs. Vitamin A, E and â-carotene for instance, have been shown to have pro-oxidant effects at higher doses or under certain conditions [39].
--
2
comments
Labels:
beta carotene,
cancer,
neurodegeneration,
nutrition,
selenium,
supplements,
vitamin A.
Labels:
beta carotene,
cancer,
neurodegeneration,
nutrition,
selenium,
supplements,
vitamin A.
Exercise and Brain Aging
There is now abundant research pointing to the beneficial effects of aerobic exercise on cerebral health. This recent study finds that taking up exercise can improve cognition and cerebral health. There is a striking relationship between cardiovascular and cerebral health. The reason for this is obvious: the brain consumes approximately 20% of our oxygen intake, so maintaining maximal blood supply to the brain is critical. One of the reasons Ginkgo Biloba works is because it reduces platelet activating factor, thereby improving cerebral circulation.
Exercise and do it often. You don't have to run marathons, in fact intense exercise can do more harm than good. Light exercise is okay but it is important to push yourself, just going for a casual walk is good but going for a brisk walk is much better.
Exercise effects on cognitive and neural plasticity in older adults
Kirk Erickson and Arthur F Kramer
British Journal of Sports Medicine (2008).
The abstract:
Older adults frequently experience cognitive deficits accompanied by deterioration of brain tissue and function in a number of cortical and subcortical regions. Because of this common finding and the increasing aging population in many countries throughout the world, there is an increasing interest in assessing the possibility that partaking in or changing certain lifestyles could prevent or reverse cognitive and neural decay in older adults. In this review we critically evaluate and summarize the cross-sectional and longitudinal studies that assess the impact of aerobic exercise and fitness on cognitive performance, brain volume, and brain function in older adults with and without dementia. We argue that six-months of moderate levels of aerobic activity are sufficient to produce significant improvements in cognitive function with the most dramatic effects occurring on measures of executive control. These improvements are accompanied by altered brain activity measures and increases in prefrontal and temporal grey matter volume that translate into a more efficient and effective neural system.
Exercise and do it often. You don't have to run marathons, in fact intense exercise can do more harm than good. Light exercise is okay but it is important to push yourself, just going for a casual walk is good but going for a brisk walk is much better.
Exercise effects on cognitive and neural plasticity in older adults
Kirk Erickson and Arthur F Kramer
British Journal of Sports Medicine (2008).
The abstract:
Older adults frequently experience cognitive deficits accompanied by deterioration of brain tissue and function in a number of cortical and subcortical regions. Because of this common finding and the increasing aging population in many countries throughout the world, there is an increasing interest in assessing the possibility that partaking in or changing certain lifestyles could prevent or reverse cognitive and neural decay in older adults. In this review we critically evaluate and summarize the cross-sectional and longitudinal studies that assess the impact of aerobic exercise and fitness on cognitive performance, brain volume, and brain function in older adults with and without dementia. We argue that six-months of moderate levels of aerobic activity are sufficient to produce significant improvements in cognitive function with the most dramatic effects occurring on measures of executive control. These improvements are accompanied by altered brain activity measures and increases in prefrontal and temporal grey matter volume that translate into a more efficient and effective neural system.
Low antioxidant status and high sunlight exposure = Retinal Degeneration
I don't know if the below is a true statement because I have never heard it before but it does highlight why even blue light is damaging to vision. Lesson: obtain sunnies with blue light filtering capacity. Take it as high risk that by the time you reach 70 there is a distinct possibility you have some degree of cataract formation and retinal degeneration. The key is to contain the progress of these conditions as much as possible. That can be done but even with the best of care some of us are going to need cataract surgery and may develop AMD. Genes! In particular, a diet specifically addressing the oxidative balance in your blood is very important.
Most importantly control cholesterol, I have seen enough research to indicate that high cholesterol, particularly the small LDL variant (vLDL), readily penetrates the Retinal Pigment Epithelium and thus sets off unwanted cascades of nasties.
http://www.sciencedaily.com/releases/2008/10/081013171431.htm
... The eye is particularly vulnerable to the damaging effects of sunlight. Ultraviolet radiation is absorbed by the lens, but visible or “blue” light penetrates to the retina so allowing us to see. Protection against the harmful effects of blue light is provided by the antioxidant vitamins C and E, the carotenoids (lutein and zeaxanthin) which filter blue light, and zinc. --------
The Aging Brain
This study from the Neurobiology of Aging highlights the significance of white matter in the aging process of the brain. The news item can be read here. White matter is the extensive sheath that surrounds the long and not so long axons of nerve cells. The presence of white matter markedly improves the speed at which signals can traverse through long axons. The process of myelination is long and we can in our late 20's or even early 30's before this process is completed.
Myelin creation is not a one off event, it is subject to continual degradation and renewal. The cells that produce myeline are called oligodendrocytes, a type of glial cell. Unfortunately oligodendrocyte cells demonstrate some particular vulnerabilities to insult. In those with Multiple Sclerosis, a common autoimmune condition, the immune processes responds to various "danger signals" emitted by oligodendrocytes and this can establish an ongoing destruction of these cells and myelin production. The initial triggers for this condition remain unknown but there are a number of strategies that Multiple Sclerosis sufferers can undertake which may alleviate the progress of the condition.
As we age the balance between myelin degradation and renewal falls out of kilter, the result being that we start losing the myelin covering. Of interest is the association between dementias and changes in white matter, it may even be the case that in some individuals the destruction of myelin is so extensive as to initiate a series of inflammatory processes that in turn induce dementias.
There is an important lesson here. The brain controls the body, maximising cerebral health is critical to maintaining good health as we age.
Saturday, October 4, 2008
Lipofuscin And Aging
Lipofuscin is the deposition of waste products in the cell that are not degraded. The critical factor seems to be rate at which proteins and lipids are degraded by the various "house keeping" functions in the cell. In these days the emphasis on the dynamics of aging is typically excessive oxidation events and lipofuscin receives little attention. Lipofuscin is something that needs to be addressed because as lipofuscin deposits increase the cell becomes increasingly unable to do its job.
In the graphic below I have extracted a table from a very old study. It highlights the huge increase in lipofuscin aggregation with age. They used acetyl l carnitine has a therapeutic intervention and the results were quite good but only at very high dosages. Other and much more recent research has found that acetyl l carnitine can also play an important role in preventing Age Related Macular Degeneration (AMD). In those studies they created a compound called Phototrop, a combination of acetyl L carnitine, omega 3 fatty acids, and co-enzyme Q10.
Word of warning: you should always use alpha lipoic acid with ALC because ALC increases mitochondrial function and mitochondria are the key region where oxidants are formed.
The table below is from
In the graphic below I have extracted a table from a very old study. It highlights the huge increase in lipofuscin aggregation with age. They used acetyl l carnitine has a therapeutic intervention and the results were quite good but only at very high dosages. Other and much more recent research has found that acetyl l carnitine can also play an important role in preventing Age Related Macular Degeneration (AMD). In those studies they created a compound called Phototrop, a combination of acetyl L carnitine, omega 3 fatty acids, and co-enzyme Q10.
Word of warning: you should always use alpha lipoic acid with ALC because ALC increases mitochondrial function and mitochondria are the key region where oxidants are formed.
The table below is from
Japan J Pharmacol, 38, 365-71(1988)
Another worrying study concerning mobile phones
There are now a number of studies pointing to the dangers of mobile phones. Of particular concern is the widespread and frequent use of mobile phones amongst teenagers. This study reveals a disturbing quality about the microwave radiation emitted from mobile phones: the markers of oxidative stress, MDA(malondialdehyde) and XO(xanthine oxidase) remain up to 40 days after exposure to the microwave radiation in a rat model. One factor causing this sustained expression of inflammatory markers was the persistent reduction in catalase, a key antioxidant pathway in our cells.
Previous research has found increased risk of brain tumours in the young. While the telecommunications industry strenously denies any danger from using mobile phones increasing research is painting a very different picture. Some authorities have even claimed that the widespread use of mobile phones is paving the way for an epidemic of brain tumours.
Thanks to Dr. Lefever for forwarding this study to me.
The full study can be downloaded here.
Previous research has found increased risk of brain tumours in the young. While the telecommunications industry strenously denies any danger from using mobile phones increasing research is painting a very different picture. Some authorities have even claimed that the widespread use of mobile phones is paving the way for an epidemic of brain tumours.
Thanks to Dr. Lefever for forwarding this study to me.
The full study can be downloaded here.
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Electric Eels and Electronic Implants
This study from Nature Nanotechnology is fascinating. They claim to have found a way to model the cells in electric eels that create electricity so that artificial cells can be used to power medical implant devices.
The news item can be read here.
The news item can be read here.
Wednesday, October 1, 2008
Financial Risk Taking and Testosterone
Previous studies have found that the higher one's position in the social ladder, the higher the Testosterone levels tend to be. In light of this study then it is not surprising that we find ourselves in this current financial predicament because financiers, for reasons which escape this humble mind, earn extraordinarily high incomes. Think about it, there are any other number of professions that should be paid more because the people in these professions have much greater responsibility and experience much greater stress than those in the finance industry. Those poor souls can't go running home to mama(the Central Banks) when they stuff up, they go broke. Financiers go running to mama and expect a handout for being naughty boys. This has to stop and I hope this crisis makes everyone take a long hard look at the financial industry.
Here is a news release on the study.
Here is a news release on the study.
The Future of Global Warming
It has always been my belief that we will never sufficiently reduce carbon dioxide output to address global warming. The simple fact is that we must find ways to capture existing CO2 AND reduce carbon dioxide output. This technology is amongst many currently under investigation.
Supplements for Osteoarthitis - Conflicting Results Again
I've seen this a number of times with various over the counter supplements. Some studies paint a good picture, others show equivocal results, and other studies claim the supplement is a dud. There is far too much hype concerning the purported value of all those supplements out there but the research is indicating that some supplements can be of great value not only in addressing specific pathologies but also general health. For example, Juvenon (see picture on the right) is a supplement compound backed up by credible research. While I haven't tried juvenon itself I have tried to the two components of it. It took a while for the effects to kick in but it definitely worked.
Osteoarthritis is a very common condition and many alternative therapists advocate the use of the supplements glucosamine and chondroitin sulfate. Studies have been mixed but mostly negative. This latest study suggests a mild favourable effect for glucosamine.
How does the consumer know what to do in these circumstances? Here are some guidelines:
Osteoarthritis is a very common condition and many alternative therapists advocate the use of the supplements glucosamine and chondroitin sulfate. Studies have been mixed but mostly negative. This latest study suggests a mild favourable effect for glucosamine.
How does the consumer know what to do in these circumstances? Here are some guidelines:
- Look for reliable well conducted clinical trials on the supplement. If these don't exist then be very careful. Typically I will never advocate the use of a compound that has not been subject to clinical trials.
- NEVER trust the sellers of a product to provide reliable information. NEVER NEVER NEVER.
- Ask others who have used the supplement for their impression of it. This may help but remember individual responses to various drugs and supplements vary so widely that there is no guarantee what works for one person will work for you. This, incidentally, is also true of clinical trials. That something has worked in a clinical trial is no guarantee it will work for you. Remember, clinical trials are statistically based and hence the results apply to the treatment group, the results may not even be applicable to individuals within the treatment group.
- As long as you are convinced the supplement is safe and even in the absence of clinical trials there is no harm in giving it a go. It may just work for you even work clinical trials make low claims to efficacy or even state no efficacy. I appreciate this sounds contradictory but we are individuals and sometimes, even if by placebo effect, people do find benefits in supplements that have no scientific support for their use.
Vitamin C May Inhibit Chemotherapy
For some time there has been a controversy regarding the use of antioxidants during chemotherapy. Concerns have been raised because antioxidants protects cells against stress and so taking large doses during chemo may impede the effectiveness of chemotherapy.
This study appears to bear that out. What they found is that vitamin C, both in vitro and in a mouse model, allowed the tumour cells to survive by protecting the mitochondria. That makes a great deal of sense because mitochondria are a "gateway" for death signals and anything that preserves mitochondrial function typically helps keep the cell alive.
Sounds simple but isn't, there is also the possibility that in some cancers activating certain functions of mitochondria, in particular the release of pro-apoptotic factors, can activate cell death pathways. Additionally some studies have found that high doses of intravenous vitamin C can be effective in killing cancer cells. What a dilemma, take antioxidants to try and prevent healthy cells from chemotherapy damage and run the risk of helping the cancer cells to survive.
Ironically part of the problem here lies in the singular tense word "cancer". Even cancer originating in the same body tissue of the same person may be a different type of cancer. Because of this, strategies to target cancer are never going to constitute a single magic bullet, we will always have to tailor the strategy to the specific type of cell present in the tumour. So in some instances antioxidants may not present a problem because in some cancers the mitochondria are disabled or poorly functioning. In other cancers improving mitochondrial function may induce death signals like APAF1, BAX, BAD. Even then it can become complicated because some cancers have high expression of the small heat shock protein, hsp27. This protein can bind these death signals so preventing cell death.
Just to confuse the picture there is clinical evidence that the intravenous administration of vitamin C can kill cancer cells. The reasons behind this are unclear but it is known that high doses of vitamin C, particularly in the presence of free iron, can drive oxidative processes via Haber-Weiss and Fenton reactions, thereby inducing cell death. To achieve such high doses though intravenous injection is required because the body will not absorb large amounts of vitamin C orally. Hence all those people taking large doses of oral vitamin C are wasting their money. For a look at the use of intravenous vitamin C read of this article. A short comment in the Canadian Medical Journal puts forward the case for using intravenous vitamin C in cancer therapy.
It is never going to be easy! So when you see all those internet advertisements proclaiming a universal cure for cancer don't go there. It simply isn't true, each type of cancer requires a different strategy. That is why the success in cancer treatments is not uniform. Great strides have been made in treating some cancers while other types, for example brain tumours, virtually no progress has been made in 20 years. In all this remember what Mencken once wrote:
This study appears to bear that out. What they found is that vitamin C, both in vitro and in a mouse model, allowed the tumour cells to survive by protecting the mitochondria. That makes a great deal of sense because mitochondria are a "gateway" for death signals and anything that preserves mitochondrial function typically helps keep the cell alive.
Sounds simple but isn't, there is also the possibility that in some cancers activating certain functions of mitochondria, in particular the release of pro-apoptotic factors, can activate cell death pathways. Additionally some studies have found that high doses of intravenous vitamin C can be effective in killing cancer cells. What a dilemma, take antioxidants to try and prevent healthy cells from chemotherapy damage and run the risk of helping the cancer cells to survive.
Ironically part of the problem here lies in the singular tense word "cancer". Even cancer originating in the same body tissue of the same person may be a different type of cancer. Because of this, strategies to target cancer are never going to constitute a single magic bullet, we will always have to tailor the strategy to the specific type of cell present in the tumour. So in some instances antioxidants may not present a problem because in some cancers the mitochondria are disabled or poorly functioning. In other cancers improving mitochondrial function may induce death signals like APAF1, BAX, BAD. Even then it can become complicated because some cancers have high expression of the small heat shock protein, hsp27. This protein can bind these death signals so preventing cell death.
Just to confuse the picture there is clinical evidence that the intravenous administration of vitamin C can kill cancer cells. The reasons behind this are unclear but it is known that high doses of vitamin C, particularly in the presence of free iron, can drive oxidative processes via Haber-Weiss and Fenton reactions, thereby inducing cell death. To achieve such high doses though intravenous injection is required because the body will not absorb large amounts of vitamin C orally. Hence all those people taking large doses of oral vitamin C are wasting their money. For a look at the use of intravenous vitamin C read of this article. A short comment in the Canadian Medical Journal puts forward the case for using intravenous vitamin C in cancer therapy.
It is never going to be easy! So when you see all those internet advertisements proclaiming a universal cure for cancer don't go there. It simply isn't true, each type of cancer requires a different strategy. That is why the success in cancer treatments is not uniform. Great strides have been made in treating some cancers while other types, for example brain tumours, virtually no progress has been made in 20 years. In all this remember what Mencken once wrote:
"For every human problem, there is a neat, simple solution; and it is
always wrong"
Tuesday, September 30, 2008
The Creative Mind: Myths and Mechanisms - Margaret Boden
Professor Margaret Boden is a cutting edge thinker in the fields of Artificial Intelligence and creativity. Recently I stumbled upon her recent publications which prompted me to re-examine some ideas about creativity. I was fascinated to find that even to this day she sets as required reading the above text. For a preview of The Creative Mind: Myths and Mechanisms click here.
This is a legendary text that should be read by all who are interested in the nature of creativity. Be warned though, this book will not provide prescriptions or rules for being creative; the author is far too intelligent and wise to lead her readers into nonsense. I read this text in 1998, it is one of the few books I have kept in my once extensive library. In these days I prefer everything to be computer based because with Google Desktop search and the brilliant Infoselect program I never loose information on my computer. The ability to track down and quickly access information is an important component of creativity.
One of the most striking concepts to emerge out of this text is that of "conceptual space". While doing some research for this post I noted that Boden is still invoking this concept in her recent books and lectures. It is a wonderful little concept that is part and parcel of my arsenal of cognitive tools. That is somewhat paradoxical because in my areas of interest there are so many conceptual spaces that I can and will keep wandering across for the rest of my days. Over recent years I have come to appreciate that creative thinking in this Big Land is 99.999999% blood, sweat, and tears and the rest is luck. That is quite common, in fact creative thinking in many realms is incredibly difficult and time consuming.
One of the fascinating aspects of the concept of "conceptual space" is that it provides insight into how discoveries can quickly proceed and then come to a standstill. As new spaces are opened up discoveries can happen quickly because there are so many good opportunities to be had. It is like a gold rush, the first in pick up the nuggets lying here there and everywhere, those following behind have to search much more harder to find the nuggets. This also explains why "mavericks" can, early on, make such huge gains. If you look at the history of science mavericks tend to succeed early in the development of the science, as the field matures mavericks, lacking the training, knowledge and expertise that comes with years of education, tend to fade into the past.
Conceptual spaces are bounded. This is a very important point. The boundaries specify the search radius and also determine the types of solutions that can be found. Einstein touched on this when he stated:
There is a tendency for people to speak about creativity as "pushing the envelope". This is also misleading. In many intellectual domains we don't have to push anything except our perseverance, there is plenty of unexplored territory. Phrases like "pushing the envelope" encourage a view that creativity is about breaking the rules and being extreme. Genuine creativity is something entirely different. As Boden states:
Boden also strongly emphasises the need for persistent effort and patience:
However she does not exclude the need for the right attitude towards creativity:
Such anecdotal stories are too common to dismiss as mere co-incidence, there are too many stories of people finding solutions to problems in such a manner. A word of caution though: Revelation comes only to the prepared mind. Forget that "muse" nonsense, people who experience Eureka moments have almost invariably been working long and hard on the problem. Often they have completely explored the available conceptual space, the breakthrough comes when they stumble upon undiscovered country. So it is not surprising that Einstein once quipped:
As to why some people have have retained that sense of fun and exploration I do not really know, though the work of Frank Sulloway may provide some insight into this matter, the truth is education can damage our curiousity. Too much of modern education is conducted in a highly competitive environment where wrong answers are punished. Yet creativity invariably involves making lots of mistakes, sometimes disastrous ones. Fear of being wrong kills creativity.
So if you are interested in improving your creative potential this book is certainly a good starting point. The text is still available and you should also consider her recent texts on the subject. I would love to add those to my reading list but I have already downloaded research articles with circa one hundred unread. Hmmm, now what was that about perseverance?
This is a legendary text that should be read by all who are interested in the nature of creativity. Be warned though, this book will not provide prescriptions or rules for being creative; the author is far too intelligent and wise to lead her readers into nonsense. I read this text in 1998, it is one of the few books I have kept in my once extensive library. In these days I prefer everything to be computer based because with Google Desktop search and the brilliant Infoselect program I never loose information on my computer. The ability to track down and quickly access information is an important component of creativity.
One of the most striking concepts to emerge out of this text is that of "conceptual space". While doing some research for this post I noted that Boden is still invoking this concept in her recent books and lectures. It is a wonderful little concept that is part and parcel of my arsenal of cognitive tools. That is somewhat paradoxical because in my areas of interest there are so many conceptual spaces that I can and will keep wandering across for the rest of my days. Over recent years I have come to appreciate that creative thinking in this Big Land is 99.999999% blood, sweat, and tears and the rest is luck. That is quite common, in fact creative thinking in many realms is incredibly difficult and time consuming.
One of the fascinating aspects of the concept of "conceptual space" is that it provides insight into how discoveries can quickly proceed and then come to a standstill. As new spaces are opened up discoveries can happen quickly because there are so many good opportunities to be had. It is like a gold rush, the first in pick up the nuggets lying here there and everywhere, those following behind have to search much more harder to find the nuggets. This also explains why "mavericks" can, early on, make such huge gains. If you look at the history of science mavericks tend to succeed early in the development of the science, as the field matures mavericks, lacking the training, knowledge and expertise that comes with years of education, tend to fade into the past.
Conceptual spaces are bounded. This is a very important point. The boundaries specify the search radius and also determine the types of solutions that can be found. Einstein touched on this when he stated:
You can't solve a problem on the same level that it was created. You have to rise above it to the next level.Note his use of the word "level". In physics that is important because they are seeking a Theory of Everything. In most domains however the idea of "levels" is misleading, Boden's concept of space is much more appropriate. Interestingly, as the physicists Lee Smolin and Paul Davies have stated, the idea of a "Theory of Everything"is eerily reminiscent of God.
There is a tendency for people to speak about creativity as "pushing the envelope". This is also misleading. In many intellectual domains we don't have to push anything except our perseverance, there is plenty of unexplored territory. Phrases like "pushing the envelope" encourage a view that creativity is about breaking the rules and being extreme. Genuine creativity is something entirely different. As Boden states:
But far from being the antithesis of creativity, constraints on thinking are what make it possible. In short, to drop all current constraints and refrain from providing new ones is to invite not creativity, but confusion.
It is the partial continuity of constraints which enables a new idea to be recognized, by author and audience alike, as a creative contribution.Her comments here touch on what I was referring to earlier. As a conceptual space is explored it soon emerges that there are constraints on one's thinking. One cannot abandon previous concepts simply to be creative, one must have very good reasons for abandoning long held concepts. It is not enough to abandon an idea simply because it gets in the way of creative thinking.
Boden also strongly emphasises the need for persistent effort and patience:
Even Mozart needed twelve years of concentrated practice before he could compose a major work, and much the same seems to be true of other composers.
This commitment involves not only passionate interest, but self-confidence too. A person needs a healthy self-respect to pursue novel ideas, and to make mistakes, despite criticism from others. Self-doubt there may be, but it cannot always win the day. Breaking generally accepted rules, or even stretching them, takes confidence. Continuing to do so, in the face of scepticism and scorn, takes even more.
However she does not exclude the need for the right attitude towards creativity:
Like much play, creativity is often open-ended, with no particular goal or aim.This reminds of a wonderful quote from that wise old Greek Heraclitus:
... Likewise, the artist or scientist may explore a certain style of thinking so as to uncover its potential and identify its limits.
Man is most nearly himself when he achieves the seriousness of a child at play.The above is not intended to suggest that creativity is solely about hard work and learning. It is obvious that Eureka! moments are important and most of us have experienced the same at various times during our lives. At least I hope most of us have. When seeking creative ideas it is important to maintain a balance. There are times when no amount of further study and conscious thinking will lead us to a solution. The mathematician Hadamard claimed that were 4 stages in his problem solving: preparation, incubation, illumination and verification. Surely all of us have experienced those occasions when the solution to a problem arises in the most unexpected circumstances. I remember an interview with the Nobel Laureate physicist Roger Penrose. He had been struggling with a particularly difficult problem for a long time. Walking with a friend on the street, the solution came to him just as he stepped off the curb to cross the street.
Such anecdotal stories are too common to dismiss as mere co-incidence, there are too many stories of people finding solutions to problems in such a manner. A word of caution though: Revelation comes only to the prepared mind. Forget that "muse" nonsense, people who experience Eureka moments have almost invariably been working long and hard on the problem. Often they have completely explored the available conceptual space, the breakthrough comes when they stumble upon undiscovered country. So it is not surprising that Einstein once quipped:
How do I work? I grope.
The important thing is not to stop questioning. Curiosity has its own reason for existing. One cannot help but be in awe when he contemplates the mysteries of eternity, of life, of the marvelous structure of reality. It is enough if one tries merely to comprehend a little of this mystery every day. Never lose a holy curiosity.The below statement is from: Cracking Creativity: The Secrets of Creative Genius, Michael Michalko
When someone asked Einstein what was the difference between him and other people he replied that if other people were asked to find a needles in haystack they would find one then give up, but he would keep looking."Creative people tend to be like that. Show them something new under the sun and you can almost see the cogs start turning. They are quizzical, fascinated by new things, want to understand these, what these things can be used for, sometimes just to understand why something works. Not all of us can be like that. In my opinion too many of us are often forced to be too practical and too concerned with outcomes rather than play. It is tragic to see so many people have lost their sense of childish fun and enthusiasm. We are taught to "grow up", "behave", and "be sensible". All that reminds me of Eric Olthwaite in Ripping Yarns when his neighbour said to him, "You're a boring little tit."
As to why some people have have retained that sense of fun and exploration I do not really know, though the work of Frank Sulloway may provide some insight into this matter, the truth is education can damage our curiousity. Too much of modern education is conducted in a highly competitive environment where wrong answers are punished. Yet creativity invariably involves making lots of mistakes, sometimes disastrous ones. Fear of being wrong kills creativity.
So if you are interested in improving your creative potential this book is certainly a good starting point. The text is still available and you should also consider her recent texts on the subject. I would love to add those to my reading list but I have already downloaded research articles with circa one hundred unread. Hmmm, now what was that about perseverance?
Monday, September 29, 2008
A Bright Side to Statins
In my earlier post, The Dark Side of Statins, I mentioned research indicating that statins may impede muscle repair. This latest finding claims that statins promote DNA repair enzymes and in so doing help protect the endothelium(inner lining of the blood vessels). The enzyme here is one involved in repairing what are referred to as "double strand breaks". These types of breaks are very damaging to the chromosomes because with the breaks bases fall away from the ends of the chromosome, so the more quickly this and other enzymes are brought into play the better the outcome. The news release can be read here.
It is important to remember that this study addressed the health and aging rate of cells in unhealthy arteries, which tend to age much faster than healthy arteries. Whether or not this statin will confer any substantial benefit to those with healthy arteries is a different question. Given the evidence that statins can induce side effects such as impaired muscle repair and there is also some evidence of cognitive issues arising with their use, there is little sense in advocating wide scale statin use for the general public. Remember the wonderful aspirin? Or how about the wonderful NSAID drugs, which turned out to be killing people and causing all manner of problems? These are great drugs but these are drugs to address specific pathologies and even then the long term use of the same may create more problems than those apparently solved.
We need to exercise some caution here. There is an emerging view that vast numbers of the public should be placed on statin drugs yet the real reason for this is because vast numbers of the public are leading lives destined to induce atherosclerosis and a host of other ailments. Claims that simply popping a statin will stave off the consequences of a poor lifestyle, even if these do have some validity, must be set against the enormous costs of drugs, the known side effects of drugs, and the unknown long term consequences of drugs.
All developed countries are faced with a number of huge health related issues. Health costs are out of control, hospitals are over crowded, and with an aging population the health burden is going to increase. We would all like to have our cake and eat it too. Eventually we will be forced to eat an apple, go for a run, and hopefully the medicine cabinet will remain empty for a very long time.
If you wish to maintain a healthy heart and cardiovascular system there is no great secret. It is as simple as regular light exercise, even just brisk walking, avoiding all drugs, legal or otherwise(excepting a couple of glasses of red wine with the evening meal), good stress management skills, and a healthy diet. Yeah, that's simple, but why can't I do it?
It is important to remember that this study addressed the health and aging rate of cells in unhealthy arteries, which tend to age much faster than healthy arteries. Whether or not this statin will confer any substantial benefit to those with healthy arteries is a different question. Given the evidence that statins can induce side effects such as impaired muscle repair and there is also some evidence of cognitive issues arising with their use, there is little sense in advocating wide scale statin use for the general public. Remember the wonderful aspirin? Or how about the wonderful NSAID drugs, which turned out to be killing people and causing all manner of problems? These are great drugs but these are drugs to address specific pathologies and even then the long term use of the same may create more problems than those apparently solved.
We need to exercise some caution here. There is an emerging view that vast numbers of the public should be placed on statin drugs yet the real reason for this is because vast numbers of the public are leading lives destined to induce atherosclerosis and a host of other ailments. Claims that simply popping a statin will stave off the consequences of a poor lifestyle, even if these do have some validity, must be set against the enormous costs of drugs, the known side effects of drugs, and the unknown long term consequences of drugs.
All developed countries are faced with a number of huge health related issues. Health costs are out of control, hospitals are over crowded, and with an aging population the health burden is going to increase. We would all like to have our cake and eat it too. Eventually we will be forced to eat an apple, go for a run, and hopefully the medicine cabinet will remain empty for a very long time.
If you wish to maintain a healthy heart and cardiovascular system there is no great secret. It is as simple as regular light exercise, even just brisk walking, avoiding all drugs, legal or otherwise(excepting a couple of glasses of red wine with the evening meal), good stress management skills, and a healthy diet. Yeah, that's simple, but why can't I do it?
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Labels:
atherosclerosis,
DNA,
endothelium,
hmg-coa,
nsp1,
public health,
repair enzyme,
statin
Labels:
atherosclerosis,
DNA,
endothelium,
hmg-coa,
nsp1,
public health,
repair enzyme,
statin
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