Our old pal David Sinclair was on TOTN Science Friday this afternoon. This was of course the fallout of this weeks sirtuin paper in Science. TOTN bungled it (typical) by hyping the red wine angle, although Sinclair, to his credit, pointed out that you'd need a hundred glasses a day to get a reasonable dose of resveratrol.
I'm not sure to what account this should be credited: it's not at all clear that
any dose of resveratrol is genuinely beneficial to normal, healthy animals (an issue that is elided repeatedly in the interview), and we know even less (and likely will continue to know even less) about the novel sirtuin-activating compounds from GSK. There is a lot more reason to think that people not predisposed to alcoholism will be better off drinking a glass or two of red wine than that they will be benefitted by taking resveratrol or its analogs.
Sinclair gets all the publicity for his work with resveratrol, meanwhile tetrahydro-curcumin has shown better results in healthy mice, and we hear nothing about it in the press.
http://www.ncbi.nlm....les/PMC3249455/
Tetrahydrocurcumin extends life span and inhibits the oxidative stress response by regulating the FOXO forkhead transcription factor
Lan Xiang,1,3,5 Yukiko Nakamura,3 Young-Mi Lim,2 Yasutoyo Yamasaki,2 Yumi Kurokawa-Nose,1 Wakako Maruyama,1 Toshihiko Osawa,3 Akira Matsuura,4 Noboru Motoyama,1 and Leo Tsuda2
There's no result here from oral administration in any mammal species; I don't think it really tells us anything worthy of press coverage.
Biogerontology. 2007 Oct;8(5):567-73. Epub 2007 May 22.
The effects of tetrahydrocurcumin and green tea polyphenol on the survival of male C57BL/6 mice.
Kitani K, Osawa T, Yokozawa T.
... Mice that started to receive diets containing TC (0.2%) at the age of 13 months had significantly longer average life spans (days, mean +/- SD) than control mice (797.6 +/- 151.2 vs.882 +/- 154.6, both n = 50, controls vs. TC treated, plus 11.7%, P < 0.01). The 10% longest survival was also significantly greater in TC-treated mice (plus 6.5%, P < 0.01). In contrast, in mice that started to receive TC in their 19th month of life, no significant difference from the control mice was found for either the average life span or the 10% longest survival. ... The body weights of the TC (but not PP) fed mice, were slightly (2-4%) but significantly (P < 0.05) lower than the values for the corresponding ages in the control mice in the first six months of treatment.
In addition to the issue raised by bixbyte (the unintended weight loss, suggesting a possible crypto-CR effect -- also seen in the NIA's ITP study(1)), this actually isn't a result worth paying attention to: it's yet another case of partially normalizing the lifespan of a colony of short-lived mice. As I keep hammering at, a normal, well-husbanded, well-fed, genetically-normal, non-toxin-fed colony of mice will live 900 d on average, 1100 max. The controls here lived just 800 d, and the TC group 12% longer -- ie, about what a colony of mice should have lived in the first place. At a guess, I'm going to say that the control group was given unlimited chow access, developed metabolic syndrome, and died early, while the TC group ate less because curcumin is pretty powerful-tasting stuff, were less overfed, got less metabolic disease, and lived more or less normal lives. Unfortunately, the authors did not monitor food intake.
The other thing is that to the extent that it worked, it was only effective in animals initiated on treatment at age 13 mo -- say, in their mid- to late- thirties in human years. That's an awfully long time to run an experiment, whether you're waiting for results or experimenting on yourself -- and an awful long time to be unwittingly doing something harmful to yourself or your patients.
Meanwhile, the baby boomers are already older than "19-mo-old mice." If it's not going to be effective in them, and if it's going to require a six decade clinical trial to test, it's not worth anyone's attention from a practical POV.
-Michael
1. Randy Strong, Richard A. Miller, Clinton M. Astle, Joseph A. Baur, Rafael de Cabo, Elizabeth Fernandez, Wen Guo, Martin Javors, James L. Kirkland, James F. Nelson, David A. Sinclair, Bruce Teter, David Williams, Nurulain Zaveri, Nancy L. Nadon, and David E. Harrison.Evaluation of Resveratrol, Green Tea Extract, Curcumin, Oxaloacetic Acid, and Medium-Chain Triglyceride Oil on Life Span of Genetically Heterogeneous Mice. J Gerontol A Biol Sci Med Sci first published online March 26, 2012 DOI: 10.1093/gerona/gls070
PMID: 22451473