The science of immortality: why do our bodies eventually stop working?

Immortality

If immortality is the absence of aging, immortality, in an organism would mean having an endless supply of telomeres. In fact, this can be possible. While storing an infinite supply of telomeres inside the cell is improbable due to the confined volume of a cell, some cells have an enzyme (a protein that performs a particular function) that repairs, synthesizes, and extends telomeres, and has the capacity to alter the cell cycle. It is called telomerase. In extension, the Faculty of Chemistry at Lomonosov Moscow State University, Russia provides more detail on telomerase research in a review: “Telomerase: structure, functions, and activity regulation.” In accord, telomerase is a pronounced feature of gametes (sperm and egg cells), stem and embryonic cells (developing cells during the early stages of embryonic development), and tumor cells.

Perhaps the most prominent example of cell immortality is the ethically debated cell culture of HeLa cells. A cell culture is a group of cells grown from a multicelled organism outside the body with precisely controlled variables such as humidity, temperature, and nutrition. HeLa cells come from the tumor of the patient Henrietta Lacks, who died of the collateralized effects from the carcinoma of her cervix (a carcinoma is a type of cancer that starts in the epithelial tissue or the lining of the organs). George Gey was among the first tissue culturists to grow Henrietta’s cells, only they were different. At this time in the 1950s, many of the cells he tried to culture died after a few days; however, HeLa cells never stopped growing. Now research shows the trace signatures of telomerase in HeLa cells. Milena Ivanković and colleagues at the Ruder Bosković Institute published a paper about telamorase activity in HeLa cells in the Journal Biogerontology, depicting the important role telomerase expression holds in proliferating HeLa cells. As a result, though Henrietta died at age 31 in 1951, her cell cultures around the world remain to flourish over 70 years after her death.

It is true that cells like these, containing telomerase, follow an uncontrollable growing pattern, which is a great danger to simply infusing all humans with telomerase enzymes to achieve immortality. Nevertheless, there appears to be an immortal organism that contains telomerase without haphazardly fluctuant cell growth. Turritopsis dohrnii is a species of jellyfish that can revert to previous phases in the cell cycle. Because this jellyfish can transform back into an infant-like state indefinitely, it bypasses aging and does not have a designated life span.

Though the idea is controversial, having biologically immortal cells and organisms is indeed possible through telomerase. However, there are extensive dangers associated with cells that have telomerase because most become malignant and grow uncontrollably. Consequently, more research is to be concluded, and immortality if achieved, may not actually be a good thing. Nevertheless, research on telomerase can be instrumental to cancer treatment and restoring endangered species. Furthermore, gene therapy and chromosomal defects may benefit from the use of available nucleotides presented by the telomerase. Likewise, embryological studies can further advance in identifying the functioning of telomerase in early-developing organisms.