By Joel C. Eissenberg, Ph.D.
A long and healthy life is the goal of most people. Many of the obstacles to this goal are obvious: infectious disease, accidents, obesity and smoking. Some of risks to longevity are more cryptic, such as high blood pressure or heart disease. For each, however, there are measures we can take to avoid risks of premature death.
In the past 25 years, considerable interest has focused on the possibility that our cells contain within them an ‘aging clock.’ If cells from our bodies are cultured in the laboratory, they can only divide a limited number of times before they cease dividing. This has suggested to some that we age because at least some of our cells run out of divisions.
One proposal is that the ends of our chromosomes—the telomeres—get shorter as we age, and that the eventual erosion of our telomeres limits the number of times our cells divide and thus limits our lifespan.
The idea that telomere erosion could limit cell division has exciting implications for cancer treatment, too. If a way could be found to promote telomere loss in cancer cells, they would stop dividing. Since cancer is result of uncontrolled cell division, this would be a magic bullet against all cancers.
Current research suggests that the key to aging is not as simple as stabilizing telomeres, and that cancer cells have more than one way to protect their telomeres. Some recent research does suggest that acute stress is associated with shorter telomeres, at least in immune cells, which may provide a link between immune disorders and stress. But at this point, healthy diet and weight remain the best predictors of longevity.
Joel C. Eissenberg, PhD, is a Professor in the Edward A. Doisy Department of Biochemistry and Molecular Biology and Associate Dean for Research at the Saint Louis University School of Medicine.
Published March 3, 2013
Editor's note: This article is part of a special series brought to you by Missouri Medicine, the Medical Journal of the Missouri State Medical Association (MSMA). MedHelp, Missouri Medicine, and MSMA are collaborating to educate and empower health consumers by making the latest scientific studies and medical research available to the public. Learn more about MSMA and see more from Missouri Medicine.
This is a summary of the article "The Methuselah Question: What are the Ultimate Limits of the Human Lifespan? Telomeres, Cancer & Aging: Live Long & Prosper?" by Joel C. Eissenberg, Ph.D., which was originally published in the February/March 2013 issue of Missouri Medicine. The full article is available here.