Chemicals that delay or reverse effects of aging.

I scan for articles on aging in my wanderings through journals and pass on the following two, on chemical compounds that delay or reverse the effects of aging:

Mowia et al. suggest the prospect of an anti-aging pill that might extend life span and delay onset of age-related diseases. They fed mice a synthetic activator of SIRT1 (NAD-dependent deactylase sirtuin 1) from 6 months of age for the rest of their (∼3-year) life span. The treated mice had 5% and 10% increases in maximum and mean life span, respectively. They also resisted many problems associated with human aging. Here's the abstract:

Increased expression of SIRT1 extends the lifespan of lower organisms and delays the onset of age-related diseases in mammals. Here, we show that SRT2104, a synthetic small molecule activator of SIRT1, extends both mean and maximal lifespan of mice fed a standard diet. This is accompanied by improvements in health, including enhanced motor coordination, performance, bone mineral density, and insulin sensitivity associated with higher mitochondrial content and decreased inflammation. Short-term SRT2104 treatment preserves bone and muscle mass in an experimental model of atrophy. These results demonstrate it is possible to design a small molecule that can slow aging and delay multiple age-related diseases in mammals, supporting the therapeutic potential of SIRT1 activators in humans.

Gervain et al. find an instance of restoring brain plasticity characteristic of early life to an adult brain with valporate, a very simple organic structure (enter 'valporate' in google images to see the structure):

Absolute pitch, the ability to identify or produce the pitch of a sound without a reference point, has a critical period, i.e., it can only be acquired early in life. However, research has shown that histone-deacetylase inhibitors (HDAC inhibitors) enable adult mice to establish perceptual preferences that are otherwise impossible to acquire after youth. In humans, we found that adult men who took valproate (VPA) (a HDAC inhibitor) learned to identify pitch significantly better than those taking placebo—evidence that VPA facilitated critical-period learning in the adult human brain. Importantly, this result was not due to a general change in cognitive function, but rather a specific effect on a sensory task associated with a critical-period.