The Serious Search for an Anti-Aging PillA report from Scientific American on scientific research to prolong life and youthful vigor. So far, only caloric restriction has been shown effective for most mammals and presumably humans as well. Unfortunately, for maximum benefit people would have to reduce caloric intake by about 1/3, and few mortals could stick to that extreme a regimen. Scientists are hopeful that it may be possible to create a pill that mimics the effects of caloric restriction without actually having to eat less. A chemical agent was discovered in the mid-1990s that produced many of the same effects as caloric restriction in lab animals -- 2-deoxy-D-glucose (2DG), which works by disrupting the functioning of a key enzyme involved in processing glucose. According to the researchers 2DG interferes with cellular production of ATP: Why might reduced functioning of the ATP-producing machinery help combat aging? We can't say with certainty, but we have some ideas. A long-standing theory of aging blames the production of molecules called free radicals. The lion's share of free radicals in the body are emitted as the ATP-making machinery operates. Over time these highly reactive molecules are thought to cause permanent damage to various parts of cells, including the protein complexes responsible for generating ATP. Perhaps by reducing the rate of ATP production, 2DG and caloric restriction slow the rate at which free radicals form and disrupt cells. Studies have shown that the hallmarks of caloric restriction are lowered glucose and insulin levels, with higher cellular sensitivity to insulin. 2DG mimics these effects, at least in rodents. Unfortunately, 2DG has also been shown to be toxic if taken for long periods or if the quantity administered is even slightly above safe levels. The narrow safety-zone is probably subject to individual differences, making it impossible to safely test this chemical on humans. Research is on-going to find a substance that has similar effect at a wider range of safe dosages. |
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