According to a new study, the protective cap on the tip of chromosomes, telomeres may play a different role in aging than it was previously considered.
Telomeres are caps on the ends of chromosomes that protect important genetic data from damage during cell division. When these telomeres enter a dormant stage known as senescence, after eroding away with every cell division, the build-up of these dormant cells causes many symptoms that are associated with aging such as age-related diseases and weakness. Now, a team of scientists from University of Montreal, Canada uncovered a different role that telomeres play in cellular aging than it is previously thought.
This new research investigated the whole process of telomeres where they provide pre-emptive protection by signaling cell to end the division when telomere wears out, and the evidence that suggests the cell division continues with even five dysfunctional telomeres. The scientists recreated cellular aging in a population of cells in the lab to induce all the telomeres to become dysfunctional, and they observed the process in every cell.
It was found that the cell division does not stop to avoid the damage to the genome due to telomeres, instead, the DNA damage accumulation drives the senescence. According to the scientists, the fact that the cells divide one last time before the start of senescence was astounding. When the telomere dysfunction cause cell division, it becomes so unstable that it creates genetic defects. As oppose to what was thought, senescent cells consist abnormal genome, as showed in the study, and the length of telomeres is still linked to aging, where finding techniques to fix them could still develop new anti-aging treatment, same as rejuvenating or clearing out senescent cells. Moreover, the build-up of senescent cells in the body causes development of diseases like cancer, and these finding could also help to create opportunities for new research.
