Friday, October 31, 2008
With Reckless Abandon We Contaminate Our Home
Wines and Heavy Metals
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 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
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
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
- 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
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
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
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
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
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
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
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].
--
Exercise and Brain Aging
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
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
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.
Electric Eels and Electronic Implants
The news item can be read here.
Wednesday, October 1, 2008
Financial Risk Taking and Testosterone
Here is a news release on the study.
The Future of Global Warming
Supplements for Osteoarthitis - Conflicting Results Again
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
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"