New Ways to Slow Down the Clock
Photo: Plamen Petkov
An inside look at how science will soon help extend the body's warranty.In the next ten years, we may not be blessed with bones that stay steel-strong into our 90s or a pill that reverses menopause, but thanks to a clearer understanding of the biology of aging, we'll soon have better ways to at least slow down the clock. (Now, if only we could defy gravity...) The highlights:
1. Menopause: In the late 1990s, scientists with the Women's Health Initiative—a government research program designed to address major health issues in older women—began studying the effects of hormone replacement therapy in postmenopausal patients. But in 2002 regulators abruptly halted the trial after they discovered that participants taking the combination of estrogen and progestin were more likely to develop breast cancer. Since then doctors have been looking for a safer option to ease menopause symptoms. According to Régine Sitruk-Ware, MD, a reproductive endocrinologist and general secretary for the International Menopause Society, the most promising is a class of drugs called SERMs (selective estrogen receptor modulators). SERMs can mimic estrogen in the body, and trigger some of the good effects of the hormone (such as stronger bones) while blocking the bad ones (such as an increased risk of certain cancers). Doctors are still working to create a SERM that can relieve hot flashes, but the drugs show promise for other common symptoms. One medication currently in clinical trials appears to reverse vaginal dryness, which affects many postmenopausal women.
2. Osteoporosis: Each day of our lives, old bone cells are breaking down while new cells are being made from scratch. As we age, though, the construction can't keep pace with the demolition, and the result is osteoporosis, a condition commonly marked by weak, easily fractured bones. Today's most widely used osteoporosis drugs—called bisphosphonates—slow bone loss, but they offer only modest increases in bone density (and can cause gastric side effects like heartburn). Future medications will boost the bone-building side of the equation. One drug in development would work by shutting down a protein called sclerostin that tells our cells to stop growing new bone. "The cells in our bones talk to each other, and if you understand the language, you can intervene and stack the deck in favor of regeneration," says Bess Dawson-Hughes, MD, director of the Bone Metabolism Laboratory at Tufts University.
3. Alzheimer's disease: Every 70 seconds someone in this country develops Alzheimer's disease. And while no cure is right around the corner, "I'm amazed at how quickly new insights are developing in this field," says Kenneth S. Kosik, MD, codirector of the Neuroscience Research Institute at the University of California, Santa Barbara. Researchers are working to create a high-tech brain scan that could spot the earliest signs of both plaques and tangles—the hard protein fragments and twisted fibers that are thought to gum up our brain's delicate wiring. And scientists are currently testing a vaccine that they hope will stimulate the body's own immune system to wipe out the plaques once they take hold in the brains of Alzheimer's patients.
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