A Sirtuin Activator Extends Lifespan in Normal Mice

If you haven't seen it, the Sinclair group and numerous co-workers at the NIH and elsewhere now report that the SIRT1 activator SRT1720 extends the lifespan of mice on a diet of normal chow, and they see a number of good metabolic indicators - increase fat oxidation, decrease fat mass, increased insulin sensitivity, and so on. There are several things to note about this effect, though. The mice were started on the compound at six months of age, and the compound was supplemented in chow to a dose of 100 mpk, which was maintained from there on out. (I don't have any allometric tables to hand, but it's safe to say that this would translate to a daily multigram dose in humans Absolutely wrong: it's about 8.8 mpk, a 600mg dose or so. Good thing I'm not a clinician). The lifespan extension was mean lifespan (up 8.8%) - they saw a trend towards extended median lifespan, but it didn't reach significance. (That sounds, at first, like there were some long-lived responders in the treatment group). There was no difference in 90th-percentile survival, which as the authors note, is consistent with the idea of the compound delaying age-related illness. There was also a high-fat-fed group of mice, supplemented in the same fashion, and consistent with earlier reports, these had their mean lifespan extended over 20%. Blood markers of liver and kidney function seemed to hold up fine. Other than less steatitis (fatty tissue inflammation) in the liver, histology didn't appear to show any major ...
Source: In the Pipeline - Category: Chemists Tags: Aging and Lifespan Source Type: blogs