Experiments with mice and controllable genes may lead the reversal of aging in humans—and one of the key factors may be the female sex hormone, estrogen. Symptoms of aging that were successfully redirected in the experiments include cognitive function, growth of the brain, and fertility.

Part of the reason we age is associated with our chromosomes’  length and safety. As we get older, our chromosomes begin aging as well, becoming shorter and more deteriorated. The study by Harvard scientists at the Dana-Farber Cancer Institute proved that by using the telomerase gene, they could prolong the protective cap at the ends of the chromosomes, called telomeres.

The experiment used the telomerase enzyme on mice as a switch to trigger the rapid deterioration of the ends of the chromosomes, which would encourage the mice to age rapidly. With the introduction of estrogen, they were able to reverse the switch and not only stop the mice from the downward aging spiral, but actually encourage regrowth of damaged tissues.

The organs in the mice that were aging the most included the spleen, intestines, testes, and the brain. Upon reversal of the damage, new cells began to grow in these organs and previous function was restored. These improvements did not prolong the lives of the mice, but rather reversed the aging process so that the mice lived out their normal life expectancy.

Scientists then tested the implications of the reversal of aging by creating a scenario using a noxious smell that would regularly alarm mice, such as decaying material. Mice who had felt the effects of aging had lost their sense of smell and could no longer detect the odor. However, when aging had been reversed, the olfactory nerves had regenerated enough cell tissue to be able to smell these vital fumes again.

In another surprising development, fertility was restored to some of the falsely-aged mice who were given estrogen, which was proven when the death-defying rodents produced larger litters.

Within a month after the reversal of aging, the mice had reproduced normal central nervous system components, including a regular sized brain, fatty protection of the spinal cord called the myelin sheath, and new nerves cells to replace the old cells. Scientists compared this reversal to Ponce de Leon’s Fountain of Youth.

Scientists are still quite a way away from knowing how this reversal might be applied to human aging. They do believe that it might be useful in helping some people who suffer from syndromes in which aging occurs more rapidly than typical aging. They are not sure that it would help reverse typical aging deterioration.

Scientists also plan to look into the telomerase age reversal with Cancer. One element that makes Cancer a difficult condition to fight is that Cancer cells have especially strong chromosomal caps (telomeres). Since scientists may be able to produce stronger telomeres, perhaps doing the opposite would help deteriorate Cancer cells. Cancer was not present in the mice that were tested.

Will science be able to turn back the hands of time? Only time will tell.

Sources: Harvard Gazette with contributions by AltMeds.com editorial staff