Miracles That May Keep You Going
Rogers, Adam, Hayden, Thomas, Newsweek
Right now the best ways of adding a few years to your life involve a lot of hard work. But medical science has a knack for making quantum leaps, as it did with vaccines and antibiotics. You shouldn't start gorging on pork rinds, or count on some future quick fix, but there are some potential "miracles" already visible on the horizons of medical research.
Chromosomes, the tight bundles of DNA that store genetic information, are capped at the ends by stabilizing sections called telomeres. Every time a cell reproduces, its telomeres get a little bit shorter, which had led some scientists to speculate that telomeres regulate overall life span. That turned out not to be the case, but telomeres do play a role in cells' aging. They seem to regulate how many times a cell can divide before it shuts down. If a way could be found to lengthen telomeres, this might prevent a host of age-related problems like atherosclerosis, immune disorders and fragile skin. Telomeres are also involved m cancer research. Cancer cells reproduce uncontrollably, and their telomeres don't shorten. At least one company, Geron, is working on inhibiting the enzyme that rebuilds telomeres.
One theory of how aging takes place is that the body's normal metabolism -- taking in oxygen and nutrients and converting them to usable materials and energy -- produces harmful byproducts. These molecules called free radicals, oxidize other molecules in the body, changing their structure in damaging ways. Over time, this damage mounts. But the body produces enzymes that act as antioxidants. In 1994 Rajindar Sohal and William Orr of Southern Methodist University genetically engineered fruit flies to make more of these enzymes. The flies lived about one third longer than they were supposed to and were more vigorous. …