If I were to go back to school for a PhD, I think I'd study telomeres. Telomeres, the protective caps at the end of each chromosome, shrink with aging and other stressors leaving an organism vulnerable to a various disorders and cancer.
So, telomere fan that I am, I was thrilled to sit in on a recent Psychiatry & Behavior Sciences Grand Rounds talk at Stanford featuring Elizabeth Blackburn, PhD. A professor of biology and physiology at the University of California, San Francisco, Blackburn won the Nobel Prize in 2009 for her work on telomeres.
During the event, she gave the packed auditorium a whirlwind overview of telomere biology. Blackburn explained to attendees that telomere length is affected by both genes and the environment, and that some folks just start out with longer ones. Telomeres are maintained by an enzyme called telomerase. Slashing the amount of telomerase can cause early, immune dysfunction, cancer and diabetes. Some genetic telomere troubles manifest as disorders such as aplastic anemia or pulmonary fibrosis.
In general, telomere length correlates with what Blackburn called a "health span," or duration of time someone stays healthy.
Recently she and colleagues measured telomere length in 100,000 people of all ages, a project they needed to develop a special robot to complete. They found that length of telomeres decreases into age 75. Then, it curves up to 95, accounting for the longevity of individuals with long telomeres. And yes, older women tend to have longer telomeres than older men.
Three years after collecting the data, the team of researchers looked at the telomeres of individuals who had died in that time period. These 2,500 people, when compared to the original group, had shorter telomeres.
Shorter telomeres have been identified in individuals with cancer, depression, dementia, lung disease and more. But, extra long telomeres have also been associated with some cancers. "It's not so simple... that (finding) threw a real curve ball into the situation," she said.
Prolonged stress and depression -- from domestic abuse, caregiving or even having less education -- can also cause telomeres to shrink. Blackburn suspects stress hormones such as cortisol and inflammation may cause these changes. Her research also indicates that education, sleep, exercise, stress reduction and omega-3 fats can boost telomere length.
Maybe we should take a cue from Blackburn herself, who meditates. Perhaps for her cellular health, perhaps for her sanity... she didn't say.
Previously: Girls at high risk for developing depression show signs of stress and premature aging, How meditation can influence gene activity and Shrinking chromosome caps spell aging cells, sniffles, sneezes... and cognitive decline?
Image by AJC1