Live Longer and Prosper
Researchers zero in on drugs to stretch out the golden years.
Working on the principle that restricting calories leads to healthier and longer lives in animals, Harvard Medical School researchers are getting closer to developing drugs that mimic the process in humans.
David Sinclair, director of the Paul F. Glenn Laboratories for the Biological Mechanism of Aging at the medical school, has over the past six years focused on a family of genes that extend the life span of simple organisms by turning on the same processes as caloric restriction. For the most part, researchers, into the 1990s, had thought no drug could be manufactured to slow the complex aging process. "Then geneticists began to uncover single genes that could dramatically extend the life span of laboratory organisms such as yeast, worms, flies, and mice," Sinclair explains on his own website. "How could this be?"
Enzymes - called sirtuins - produced by these genes govern the speed of aging by altering the body's energy consumption and by protecting cells from damage. "The genetics say we have found longevity genes that determine how long [mice] live and how healthy they are," says Sinclair. "They set the pace of aging." But directly altering similar genes in humans is not a practical approach. And the extreme calorie restrictions that might trigger the life-extending response would be difficult for many people and inadvisable for sick or elderly patients. Sinclair is now testing synthetic molecules that activate the sirtuin enzymes in mice. Besides measuring their impact on life span, he is testing the molecules' effect on diseases such as Alzheimer's, diabetes, and cancer. So far, results "look interesting," he says.
"What we need are small molecules that can be either injected or consumed as a pill," says Sinclair. "What we expect to see from such a pill is the ability to prevent and treat many of today's major diseases." His prediction: Look for the first of such drugs within the next five years.
A Toast to Life
Drinking alcohol in any form - in moderation - appears not only to lower your risk of heart disease but also to improve glucose tolerance. Moderate drinkers have a lower risk of type 2 diabetes than do teetotalers. Moreover, if diabetics have one or two drinks every day or most days, they have a lower risk of heart disease compared with diabetics who don't drink, says Dr. Meir Stampfer, chairman of the Harvard School of Public Health's epidemiology department. "Maintaining healthy weight and exercise are most important, but moderate alcohol can also be beneficial for both heart disease and diabetes," Stampfer said.
The Dangers of Depression
Evidence is mounting about the dangers of late-onset depression. Heart-attack survivors face an increased risk of dying if they experience depression afterward, research shows, and individuals who have a depressive episode for the first time in later life may face an increased risk of recurrent depression and possibly dementia. Short-term cognitive behavioral therapy is an effective form of psychotherapy for older adults with depression, and SSRIs, including sertraline (Zoloft) and citalopram (Celexa), are among the best-tolerated medicines, says Dr. Brent Forester, director of the Mood Disorders Division of the Geriatric Psychiatry Research Program at McLean Hospital in Belmont.
(Globe Staff Graphic / David Butler)
Visionary Thinkers
A new generation of treatments offers hope for sufferers of macular degeneration, the most common cause of major vision loss. The so-called wet form of the disease is marked by abnormal growth of leaking blood vessels that cause scar tissue to form within the retina. Current therapies slow vision loss by destroying the abnormal vessels. Now, new drugs block a particular protein promoting the abnormal growth. Most recently, one called Lucentis was shown in a large clinical study to actually improve vision in many patients, says Dr. Joan Miller, chief of the Department of Ophthalmology at Massachusetts Eye and Ear Infirmary. Miller, who did early work on the protein and serves as ad hoc consultant for 