Benefits of Meditation:
Telomerase and Anti-Aging
What is Telomerase?
Put simply telomerase are the end segments of chromosomes, which form a ‘capped’ structure at the end. The telomerase protect the end of chromosomes from degeneration which is a consequence of replication. They do this by providing as a buffer zone for expendable DNA and by acting as substrates for telomerase to come in and extend the Telomerase by adding extra copies of repetitive DNA¹.
It was in the year 1973, when Alexey Olovnikov predicted how telomerase worked. But it was in 1985 that the actual discovery was made by Carol Greider and Elizabeth Bluckburn. Together with Jack W. Szostak, they were awarded the 2009 Nobel Prize in Physiology and Medicine.
How does aging occur?
As already stated above, telomerase are proteins that are our like the caps at the end of our chromosomes, which are actually paired strands of DNA. When the process of genetic copying of our cells takes place, Telomerase act like the white space in the copying process to prevent errors in the duplication of the cells. However, every time a cell divides a very small portion of the telomere does not get copied, or in other words, the Telomerase begin to shrink. Every time the cells divide, Telomerase are shortened leading to cellular death and damage and resulting in aging.
Some scientists refer to telomerase as age counters or markers. They are somewhat like a ‘biological clock’ that is constantly tickling down and imposing a limit on the human lifespan. The agreed limit currently on the human lifespan is 125 years.
The Telomerase Theory of Aging
The telomerase theory of aging holds many promising possibilities for the field of anti-aging medicine. This theory gained momentum from the surge of technological breakthroughs in genetics and genetic engineering.
As stated above, Telomerase are sequences of nucleic acids extending from the ends of chromosomes. The telomerase theory of aging is based on the ‘immortalizing’ powers of the enzyme telomerase, an enzyme found only in germ cells and cancer cells. Research shows that this enzyme ca repair and replace Telomerase thereby manipulating the “clocking” mechanism that controls the life span of dividing cells. In other words, the telomerase enzyme provides limitless proliferative potential to most human cells through its ability to elongate Telomerase at the ends of chromosomes.
Evidence in support of the telomerase hypothesis of aging²
- Telomerase are shorter in most tissues from older individuals compared to younger individuals.
- Children born with progeria (early aging syndrome) have shortened Telomerase compared to age-matched controls.
- Telomerase in normal cells from young individuals progressively shorten when grown in cell culture.
- Experimental elongation of Telomerase extends proliferative capacity of cultured cells.
The role of telomerase in checking aging remained unaddressed, in part because of the cancer-promoting activity of telomerase. In order to circumvent this problem, scientists have successfully tested telomerase reverse transcriptase (TERT), one of the components of telomerase, in mice and have shown that it could restrain cancer. The test revealed that TERT could improve the fitness of epithelial barriers, particularly the skin and the intestine. It also produced a systemic delay in aging accompanied by extension of the median life span.
- Chopra, R., M. Dougal, R. E. Gale, D. C. Linch, J. D. Robertson, N.G. Testa, and R. F. Wynn. 2000. Dynamics of Telomere Shortening in Neutrophils and T Lymphocytes during ageing and the relationship to skewed X Chromosome Inactivation Patterns. British Journal of Hematology. 109:272-279.
- Jerry W. Shay and Woodring E. Wright Telomerase and telomerase in the regulation of human cellular aging. The University of Texas Southwestern Medical Center,
Department of Cell Biology and Neuroscience