The Science of Telomeres

We all know those people who seem younger than their actual age. They seem to stave off wrinkles and have the energy and metabolism of a fifteen-year-old, but are well into middle age.

Common sense dictates that exercise, diet, and sleep can influence aging, but research of Nobel Laureate Elizabeth Blackburn and psychologist Elissa Epel suggest that telomeres may be the key to understanding the aging puzzle. Telomeres are tiny caps on ends of our DNA strands that protect cells from premature aging. As we age, these telomeres get shorter. When they get too short, cells can go into an aged and unhealthy state called senescence. This is a state where cells can no longer divide and replenish tissue, or even die. Short telomeres predict early onset of age-related diseases such as heart disease, stroke, some types of cancer, diabetes, and dementia.

In a recent study, a group of scientists at the Spanish National Cancer Research Centre (CNIO) generated first mice that have hyper-long telomeres in every one of their cells. The researchers generated these mice from embryonic stem (ES) cells that carry hyper-long telomeric repeats.

They observed that these mice have less DNA damage with aging. They are generally lean, have low cholesterol and LDL levels, and have improved glucose and insulin tolerance. Incidence of cancer among these mice are also much lower compared to normal mice, which ultimately increase longevity.

Achievements of this study can be summed up in two points. First, longevity was increased without any genetic modification for the first time. Second, the findings demonstrate that longer telomeres are not harmful, but instead have beneficial effects. This goes against the notion that long telomere length is associated with cancer.

Blasco and colleagues published their findings in Nature Communications Journal in an article titled, “Mice with hyper-long telomeres show less metabolic aging and longer lifespans.” Their findings could feasibly pave way to the development of new approaches to increase longevity without resorting to genetic manipulation.

References:
Nature Communications volume 10, Article number: 4723 (2019) https://www.nature.com/articles/s41467-019-12664-x