By Macleans.ca
The quest for a youth pill
Why scientists think they have one, and why you can’t get it
Award-winning journalist David Stipp has been writing about science
and medicine since 1982, first at the Wall Street Journal and then
Fortune magazine. In his new book, The Youth Pill: Scientists at the
Brink of an Anti-Aging Revolution, he explains that slowing down aging
is no longer a fantasy. After centuries of such anti-aging “remedies”
as injecting minced dog testicles, scientists have recently discovered
compounds that could dramatically extend human longevity and health
Q: What’s the brass ring in anti-aging research?
A: The near-term, totally feasible prospect scientists are
working toward is the development of a safe drug that delays by seven
or eight years the onset of diseases associated with aging. The goal is
to slow the rate of aging and postpone all the bad stuff: Alzheimer’s,
cancer and heart disease are the three main killers, and then there
are lesser diseases, from osteoporosis to cataracts. A true anti-aging
drug would also extend maximum lifespan.
Q: As you explain in your book, scientists already know
how to do all that in animals: cut their caloric intake by a third and
they live 30 to 40 per cent longer than animals on a regular diet.
A: Calorie restriction (CR) revs up antitoxin defences, and
that’s probably at the heart of why it has been shown, very robustly, to
work across a wide range of species. The theory behind it is that if
there’s less food, animals eat whatever they can get, including
poisonous stuff. The only way you’re going to survive that is if you’ve
got all these forces in play that fend off free radicals and
everything else that basically makes you get old and sick. You can’t
look at CR without thinking, “Evolution has built this mechanism into
the genome.” From a natural selection point of view, it makes a great
deal of sense to install a special device in the genome of many animals
that would let them go into slow aging mode when food is scarce: they
can hunker down and wait until the famine’s over to reproduce,
therefore improving the chances their genes will be carried on.
Q: Doesn’t CR make them less healthy?
A: The opposite seems to be true. One study of rhesus monkeys
showed those on CR had greater lean muscle mass, significantly less
age-related brain atrophy, half as much cancer and half as much
cardiovascular disease as those on normal diets. And when pathologists
examined the tissues of calorie-restricted rodents after death, in a
fourth to a third of the animals, there were no visible signs of severe
age-related diseases. It’s as if they lived to ripe old ages then
suddenly dropped dead without any terminal decline at all.
Q: Does CR work in humans?
A: It hasn’t been proven, so it’s not a sure bet, but it seems
to me that it should work given everything we know about what it does
in other species. However, it’s very tricky to get all the nutrients
you need, and there are risks. CR affects fertility, for one. The first
downside is hunger. I tried CR and lasted a little over two days. I
couldn’t get any work done. I was thinking about food all the time.
Q: I guess that’s why scientists are focusing on finding
compounds that mimic the anti-aging effects of CR, minus the
unpleasantness. How promising is resveratrol, a compound found in red
wine and peanuts, as a CR mimetic?
A: The most exciting data come from two studies of rodents on
high-fat diets. The decline normally associated with that kind of diet
didn’t happen to the mice on resveratrol: their livers didn’t get
filled up with fat, their hearts seemed to be protected better. Several
other studies suggest that high doses of resveratrol can cause
formation of new mitochondria, which are these little power plants in
all of our cells. There’s a lot of previous research suggesting that
your mitochondria getting flaky is at the very root of what makes you
get old-maybe not the whole story, but a very major part of it. So if
resveratrol causes formation of mitochondria, it’s probably what
accounts for those videos we’ve seen of mice on high doses being able
to run on treadmills a whole lot faster and farther than mice that
haven’t taken it. The implication is that even if resveratrol doesn’t
extend lifespan, it might extend health span.
for more go to: posted August 1'10 by
Renee@insideouthealth