Nutrients and Longevity

Today I read an interesting article in the New York Times that reminded me of earlier studies I had read. To read the full article you need to register with the NY Times. That is free and I recommend it because the health articles are amongst the best I've encountered in the mass media. (They will protect your privacy.) Balanced, referencing actual research, and the articles are very easy to read. The companion articles in relation to this issue can be read here, and here.

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.
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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.
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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.
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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]
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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].
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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.
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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.
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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].
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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].
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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].
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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:

1. 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.
2. NEVER trust the sellers of a product to provide reliable information. NEVER NEVER NEVER.
3. 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.
4. 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.