Immune cells (stained blue) end in protective caps called telomeres (stained yellow) that are shorter in the elderly — and in persons suffering chronic stress. A new UCLA study suggests cortisol is the culprit behind premature aging of the immune system in stressed-out people.
Every cell contains a tiny clock called a telomere, which shortens each time the cell divides. Short telomeres are linked to a range of human diseases, including HIV, osteoporosis, heart disease and aging. Previous studies show that an enzyme within the cell, called telomerase, keeps immune cells young by preserving their telomere length and ability to continue dividing.
UCLA scientists found that the stress hormone cortisol suppresses immune cells’ ability to activate their telomerase. This may explain why the cells of persons under chronic stress have shorter telomeres.
The study reveals how stress makes people more susceptible to illness. The findings also suggest a potential drug target for preventing damage to the immune systems of persons who are under long-term stress, such as caregivers to chronically ill family members, as well as astronauts, soldiers, air traffic controllers and people who drive long daily commutes. – read the full article on scidaily