Extra Credit for Friday, July 22: Stress and ageing: A question of attitude: The link between chronic stress and a marker of old age is being disentangled

Stress and ageing
A question of attitude
The link between chronic stress and a marker of old age is being disentangled
Apr 7th 2011 | from the print edition

Chromosomes, which are located in white blood cells, replicate themselves as the cells they are in divide. The telomeres, which stop the chromosomes from "fraying", shorten every time the chromosome is divided. According to the Hayflick limit, telomeres can only divide 50-70 times; after this many divisions, the chromosome is unable to divide any further. Although it is a good thing that when quickly dividing cells in a tumor hit the Hayflick limit they stop dividing completely, reaching the Hayflick limit is also an indication of old age. It is not good for this halt in dividing to happen prematurely, for tissues, like the tissues in the immune system, have to be dividing constantly in order to function properly. Chronic stress, defined as the response to emotional pressure suffered for a prolonged period over which an individual perceives he or she has no control over, such as from suffering from an illness, is known to cause premature shortening of the telomeres. A group of researchers led by Edward Nelson of the University of California, Irvine, at a meeting of the American Association for Cancer Research, answered a question that has been unanswered: Is premature shortening of the telomeres irreversible? Although the results must be treated carefully, the research Edward Nelson and his team conducted seems to show that stress management is the key; it stops telomeres from shortening AND it promotes their repair. In order to reach this conclusion, a study Nelson and his group of researchers involved counseling women who suffered from chronic stress due to cervical cancer with telephone counseling, and of course, a control group of women who did not receive counseling. Although the women who were counseled still had cervical cancer, they reported that the quality of their lives had improved, as well as the strengths of their immune systems. In order to analyze these results, Dr. Nelson examined the white blood cells of the women who endured counseling. He found that counseling reset their Hayflick countdowns; the counseling not only stopped the shrinkage of their telomeres, but promoted their growth! Elizabeth Blackburn of the University of California, San Francisco, supported Dr. Nelson's results by showing that like counseling, exercise also has a similar resetting effect on the telomeres with her Nobel Prize winning discovery of the enzyme that repairs telomeres. Dr. Nelson's work should be replicated in order to contribute to an expansion of knowledge of the relationship between the mind and the body, but from his results, it is safe to say that positive attitude not only helps the state of mind, but the health of the body as well.

http://www.economist.com/node/18526881