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Molecules found in red wine, peanuts and other products of the
plant world have for the first time been shown to mimic the life-extending
effects of calorie restriction, a finding that could help researchers
develop drugs that lengthen life and prevent or treat aging-related
diseases.
Resveratrol, was shown in a study to extend the life span of yeast
cells by up to 70%. Howitz et al report the discovery of three
classes of small molecules that activate sirtuins,showing that
the potent activator resveratrol, a polyphenol found in red wine,
lowers the Michaelis constant of SIRT1 for both the acetylated
substrate and NAD+, and increases cell survival by stimulating
SIRT1-dependent deacetylation of p53. In yeast, resveratrol mimics
calorie restriction by stimulating Sir2, increasing DNA stability
and extending life-span by 70%. The researchers discuss possible
evolutionary origins of this phenomenon and suggest new lines
of research into the therapeutic use of sirtuin activators. David
Sinclair, an assistant professor of pathology at Harvard Medical
School, said he and his fellow researchers hope the molecules
will prove to prolong life not just in yeast but in multi-cellular
organisms like worms, fruit flies and, perhaps, humans.
Sinclair said the study may help explain why moderate consumption
of red wine has been linked to lower incidence of heart disease
and why resveratrol prevents cancer in mice. Scientists know that
putting organisms on a calorie-restricted diet reduces the incidence
of age-related illnesses such as cancer, osteoporosis and heart
disease. In the 1990s, research showed that single genes can control
how fast organisms age. Scientists have been racing to find ways
of manipulating those genes by finding molecules that activate
the enzymes that in turn influence the genes that regulate aging.
Sinclairs team screened thousands of molecules to see which ones
might activate the enzymes.They found a group of 18 molecules,
resveratrol being just one, and all of them came from plants and
were produced in response to harsh environmental conditions like
drought.To illustrate that theory, Sinclair noted that red wines
from regions with harsher growing conditions- Spain, Chile, Argentina
and Australia- contain more resveratrol than those produced where
grapes are not highly stressed or dehydrated.
Professor R. Curtis Ellison comments We have a huge amount of
direct data in humans on the effects of alcohol and wine in preventing
disease, especially the diseases associated with aging, such as
heart disease, stroke, osteoporosis, and Alzheimers Disease.
If anyone wants to base public policy on research, it should at
least be based on studies in humans (not studies in worms, fruit
flies, and mould!). The vast amount of interest in this paper
is because it raises the possibility that some companies can isolate
a single substance from wine (or other matter) and make a big
profit from putting it into a capsule.
I believe that there are probably hundreds of active substances
in wine other than resveratrol that have healthy properties. And
it is probably the resveratrol in conjunction with many other
substances, especially the alcohol, that will turn out to be the
healthiest "drug" we should be taking. St. Leger, Cochrane and
Moore published a classic paper in 1979 describing the inverse
association between the average per capita wine consumption of
a country and its mortality rates of coronary disease (Lancet
1979;1:1017-1020). These authors ended their paper by stating:
"If wine is ever found to contain a constituent protective against
I.H.D. (ischemic heart disease, or coronary disease) then we would
consider it almost a sacrilege that this constituent would be
isolated. The medicine is already in a highly palatable form."
SOURCE: Howitz KT et al. Small molecule activators of sirtuins
extend Saccharomyces cerevisiae lifespan. Nature 2003. |