Chapter 6 - Telomerase reactivation for anti-aging

Abstract

Aging is a process which leads to the deterioration of cell cycle; it also changes the morphology of cell as well as brings out functional and structural changes in chromosomes. This is an intricate mechanism that also affects the metabolism of an individual. There are several pathways involved which are responsible for this process of aging in humans. Also, there are plenty of other factors like genetic and environmental factors which can also cause early aging. Genetically, aging is also linked to the length of telomeres. Telomeres are situated at the end of a chromosome with a specific protein complex, which helps in cell division and protects genome stability. These are short continuous sequences composed of double-stranded DNA on the terminals of the chromosome. Adopting a healthy lifestyle optimizes antiaging factors like a longer length of the telomere. Therefore modification in the telomere length can also help in increasing the lifespan of an individual. At every cell division process, the length of the telomere declines and it maximizes the risk of diseases and cell denaturation. Telomerase is an enzyme that can correct the defective telomere into a functional chromosome. Telomerase is a broad multisubunit of ribonucleoprotein (RNP), which has conserved and continuous sequences present at the 3′ end terminal of the eukaryotic chromosome. This helps in maintaining the purity of genomic DNA. Under conditions when DNA polymerase is incapable of copying 50 ends of chromosomes, telomerase functions as RNA-dependent DNA polymerase which synthesizes DNA in the 3′ to 5′ direction. The shortening of telomeres in stem cells directly reduces their number which could lead to aging as well. However, activation of telomerase can reportedly improve the capability of the DNA repair mechanism and prevents the cells from undergoing DNA damage and stress conditions. Therefore telomerase activators play an important role in accomplishing therapies for antiaging and diseases related to telomeres.