Fight Aging!

Average telomere length in blood cells tends to decline with advancing age, but it is a dynamic measure that should probably be regarded as an indirect reflection of health and robustness. Consider that telomeres shorten with each cell division, acting as a part of the mechanisms that limit somatic cell life span, so the average telomere length in any given tissue is a function of how rapidly cells divide and how often they are replenished from the supporting population of stem cells in which telomerase activity maintains long telomeres. It isn't clear at all that telomere erosion is an important cause of aging, versus simply a secondary effect of damage taking its toll on stem cell activity and other necessary aspects of tissue maintenance. Given that, it is interesting that telomerase based treatments extend life in mice: the mechanism has yet to be established, however, and there are hints that it may have something to do with the effects of telomerase on mitochondria.

Separately, in recent years researchers have demonstrated that greater time spent sitting, independent of other factors relating to exercise and sedentary behavior, correlates with worse health and a shorter life expectancy. Various researchers are exploring mechanisms that might explain these results. Here this group shows a correlation with telomere length, which would be expected if sitting time does indeed correlate with worse health:

[Researchers] analysed the length of chromosomal telomeres in the blood cells of 49 predominantly sedentary and overweight people in their late 60s, on two separate occasions, six months apart. All 49 participants had been part of a previously reported clinical trial in which half of them had been randomly assigned to a tailored exercise program over a period of six months, and half had been left to their own devices. Levels of physical activity were assessed using a seven day diary and a pedometer to measure the number of footsteps taken every day, while the amount of time spent sitting down each day was gleaned through a validated questionnaire. The time spent exercising as well as the number of steps taken daily increased significantly in the group following the exercise program, while the amount of time spent seated fell in both groups.

Various risk factors for heart disease and stroke also improved in both groups, particularly those on the exercise program, who also lost a great deal more weight than their counterparts left to their own devices. But increases in physical activity seemed to have less of an impact than reductions in sitting time, the findings showed. The number of daily steps taken was not associated with changes in telomere length, while an increase in moderate intensity physical activity was linked to a shortening in telomere length, although this was not significant. But a reduction in the amount of time spent sitting down in the group on the exercise program was significantly associated with telomere lengthening in blood cells.

Link: http://www.sciencedaily.com/releases/2014/09/140903204123.htm