In an article published online in Maclean’s magazine on May 14, 2013, postulated hypotheses regarding the potential cellular pathophysiology of longevity are summarized. Telomeres, telomerase, and telomerase activators each—individually or in concert—may have a critical role in this process.
Telomeres, the tiny bits of DNA that cap the ends of chromosomes, shorten each time a cell divides and also as people age. Telomeres function to prevent chromosomes from unraveling and fusing with each other, yet when they become too short, the cell dies. Shorter telomeres have been observed in patients with chronic stress, such as mothers of children with chronic illnesses and spouses who care for parents with Alzheimer disease; domestic abuse victims; and individuals with untreated depression. Several systemic conditions also are associated with shorter telomeres, including cancer, cardiovascular disease, dementia, diabetes mellitus, and osteoporosis. However, individuals who are older than 100 years have remarkably long telomeres. Hence, telomere length may be a more accurate indicator of a person’s physiologic age than one’s date of birth.
Telomerase, an antiaging enzyme, rebuilds telomeres and protects them from wearing down. Lifestyle changes, such as diet (with increased omega-3 fatty acids found in fish oils), exercise (approximately 30 minutes 4 or 5 times a week), and meditation, can potentially slow down the shortening of telomeres, increase telomerase activity, or both. Experiments performed on genetically engineered mice with a controllable telomerase gene show that when the enzyme is turned off, it becomes prematurely old, mentally impaired, and infertile. However, even after the mice reach this state of severe degeneration, the changes reverse when the gene is turned on again; the mice eventually resemble young active adults, with a healthy sheen restored to their hair coat, improved cognition, and restored fertility.
Telomerase activators, products that can stimulate telomerase, are the next logical progression in this quest to remain young. Indeed, at least one agent is commercially available (and sold as a nutritional supplement); however, the US Food and Drug Administration has not approved the oral agent.
What’s the issue?
The skin is the largest organ of the body. It is reasonable to speculate that the aging of one’s skin may be related to overall senescence. Therefore, the cellular longevity of a person’s keratinocytes also might be related to the length of their telomeres. Increasing the telomerase activity of these keratinocytes should favorably influence the length of the telomeres. To the best of my knowledge, a topical telomerase activator remains to be developed. However, it is very intriguing to consider the potential possibilities of a new topical cutaneous antiaging agent. Will the next antiaging agent for the skin be a topical telomerase activator?