Age-old woes, new tactic

“Even my own colleagues thought I was nuts,’’ said Guarente, whose studies of the metabolic pathways in yeast cells might lead to drugs that reverse and prevent aging. “But the scientific community has done a complete 180 in the past 20 years.’’

Dramatic advances in the understanding of what causes cells to live and die are making such scientists as Guarente look less like New Age alchemists than the founders of a field of medical research.

Guarente was among the scientists who took part in the Aging and Healthy Lifespan Conference at Harvard University last month. The conference, sponsored by the public relations firm for Cambridge biotechnology company Sirtris Pharmaceuticals Inc., highlighted the company’s vision for antiaging medicine, in which single compounds prescribed to treat a specific disease, such as diabetes, might also have “antiaging’’ benefits. Such an approach, company officials say, is more conducive to approvals from the Food and Drug Administration.

“We’re not going after aging,’’ said Christoph Westphal, chief executive of Sirtris. “We are focused on getting FDA approval for treating diseases, and the FDA does not consider aging to be a disease.’’

Sirtris’s drugs - if they are approved by the FDA - will be available by prescription to patients with diabetes, cancer, or another disease frequently associated with aging.

But Sirtris’s drugs are products of the same research that suggests lifestyles and chemical compounds could extend life.

Sirtris’s timing could not be better, as baby boomers feel the effects of lifetimes of excessive consumption. (The British pharmaceutical giant GlaxoSmithKline PLC bought Sirtris last year.)

One recent population study predicted that the number of Americans over 65 will double in the next 20 years. And chronic diseases will follow many of those boomers into their old age. The Alzheimer’s Association, for example, estimates 10 million boomers will develop the devastating brain disease unless effective treatments and interventions are developed soon.

The drugs in Sirtris’s pipeline are aimed at treating two diseases associated with aging: type 2 diabetes and cancer. The drugs target sirtuins, the enzymes identified by Gaurente and others as regulating cell metabolism.

Sirtris is reporting that one of its drugs, SRT501, had lowered blood glucose levels and insulin resistance in human trials.

“The science has gone extremely well,’’ said Guarente, who is a scientific adviser to Sirtris.

Much of the discussion at the Harvard lifespan conference centered on sirtuin modulators, which appear to provide the same benefits as calorie restriction (CR) - a practice enthusiasts believe will extend their life spans. Their faith is based on the results of studies with yeast, flies, and primates.

Typically, such diets require cutting daily calorie intake by up to 30 percent. For someone consuming 2,000 calories per day, that would mean scaling back by 600 calories.

Resveratrol, found most abundantly in red wine and Japanese knotweed, is the best-known sirtuin modulator. Many scientists speculate that the resveratrol in red wine is behind the “French paradox,’’ the low incidence of heart disease in the French despite their love for fatty foods.

Sirtris’s SRT501 is a highly concentrated formulation of resveratrol. The company says its other drug, SRT2104, is 1,000 times more powerful than resveratrol.

Sirtris is not the only drug maker developing sirtuin modulators. Elixir Pharmaceuticals Inc., also based in Cambridge, says it has three such drugs in early development.

Since the heyday of Omni - the science fact and fiction magazine founded by the longevity-obsessed publishers Bob Guccione and Kathy Keeton - in the 1980s, boomers have wanted to keep their party going.

But throughout the 1990s, talk of longevity medicine sounded more like a fictional pursuit for the philosopher’s stone than science, said Harvard molecular biologist Raul Mostoslavsky.

“I’m not going to say the research discussed was esoteric,’’ said Mostoslavsky, who also spoke at the Harvard conference. “But the basic biology behind it was basically zero.’’

Since then, “we’ve made huge advances in understanding the metabolic pathways behind cellular aging, and how to influence those pathways,’’ he said. “We’re definitely much better at it than we were 15 years ago.’’

Mostoslavsky cautioned that the workings of the media’s favorite “magic bullet’’ - resveratrol - are not fully understood by scientists.

For example, resveratrol’s ability to extend life spans of mice on high fat diets - a finding that has contributed to red wine flying off the shelves at grocery stores - is being exaggerated in the media, he said.

“The work done so far,’’ he said, “doesn’t say that you are having an extension of life span, just that the organism is handling a high fat diet better.’’

James Wessler, chief executive of the Massachusetts and New Hampshire chapters of the Alzheimer’s Association, pointed out that dietary and lifestyle changes are key for individuals who want to live longer.

At the Harvard conference, Wessler shared what he called “a cascade of large epidemiology studies, which show that lifestyle, a heart-healthy diet, and social and cognitive engagement,’’ can postpone or prevent Alzheimer’s.

“It’s not as sexy as a magic bullet,’’ he said. “But until we have significant disease modifying drugs [for Alzheimer’s] it is the best route.’’