Telomeres are the “protective caps” found on the end of chromosomes, and they are important to preserve the genetic information encoded in chromosomes during the process of cell division. The protection of genetic material is of paramount importance so that it can express all the genes properly and avoid the wayward deterioration that could lead to be a potential cancerous cell.
The aglets of our genome
A simple way to understand the role of telomeres is to consider them as the aglets of our genome. Shoelaces have aglets to protect the lace ends and keep them from fraying. Similarly, telomeres are the protecting tips at the end of DNA molecules and help in stabilization, and give protection against the chromosomal recombination or fusion. With every cell division, telomeres gradually become shorter, thus exhibiting a mitotic clock phenomenon, and ultimately reaching a critical point which brings the cell to senescence (the organic process of growing older, which we’ve touched on before).
It has been proposed that telomeres shorten with age or with the development of disease, depending on the number of cell divisions. Regardless of the association with longevity, telomere length warrants further investigation. It is a bizarre question; are shorter telomeres just predictive of cancers and other disease processes, or are unhealthy body conditions and disease processes actually responsible for the shorter telomere lengths? However, lifestyle factors including exercise and diet have shown a considerable effect on telomere lengths.
Physical activity as an anti-ageing trigger
Physical activity has been hailed as one of the important anti-ageing triggers in the general population. Evidence suggests that endurance exercise could maintain the telomere lengths in older people compared with their sedentary peers. Even the telomere lengths of older active people are comparable to active young adults.
The telomere length and their role as anti-ageing precursors depend on nature and amount of exercise. Irrelevant of cell type, moderate physical activity levels may provide a protective effect on telomere length compared to both low and high physical activity. However, aerobic exercise at 80-90% maximal capacity may help to keep telomere lengths at youthful levels in leukocytes (white blood cells). In skeletal muscles, telomere lengths could be compromised in response to strenuous exercise (lifting heavy weights) or exercise-induced fatigue.
Ultimately, telomere length plays a pivotal role in the process of ageing, and physical activity could help to maintain them, and provide an important tool for healthy long living.
For more information about telomeres and their role in ageing process, see this video from 2009 Nobel laureate Professor Elizabeth Blackburn (Nobel Prize in Medicine):
Written by Javaid Nauman, Post doctor at CERG.