Telomeres are the protective caps at the ends of chromosomes that preserve genetic information during cell division. Telomerase is an enzyme that adds repetitive DNA sequences to these telomeres, effectively replenishing them and allowing cells to continue dividing and functioning correctly.
However, in most adult somatic cells (non-reproductive cells), telomerase activity is typically low or non-existent. This absence of sufficient telomerase leads to the gradual shortening of telomeres as cells divide. When telomeres become critically short, it can trigger cellular senescence, apoptosis, or genomic instability, all of which are associated with aging and various diseases, including cancer.
- Aging and age-related diseases: As telomeres shorten, cells lose their ability to function properly. This contributes to aging and the development of age-related diseases like heart disease, diabetes, and neurodegenerative disorders.
- Cancer: On the other hand, many cancer cells reactivate telomerase or employ alternative mechanisms to maintain their telomeres, which allows them to bypass cellular senescence and apoptosis, leading to unlimited cell division and tumor progression. This makes telomerase a potential target for cancer therapies.
- Genetic disorders: Certain genetic disorders, such as dyskeratosis congenita, are caused by mutations that impair telomerase function, leading to extremely short telomeres and a variety of symptoms including bone marrow failure and a higher risk of cancer.
It’s important to note that while telomerase activation could potentially counteract aging, it’s not as simple as it might seem. There are risks involved, such as the potential for increased cancer development, and more research is needed to fully understand the complex role telomerase plays in human biology.
