Cover Stories

Shortening Telomeres Gracefully

Interview with Elizabeth Blackburn

– Professor of Biology and Physiology and a Nobel laureate

by Halima Hassan

 

[dropcap]T[/dropcap]he Nobel Week Dialogue is an annual event that takes place in Stockholm where previous Nobel laureates are invited to discuss a particular theme. This year’s event was focusing on aging and attendees included Professor Elizabeth Blackburn. Blackburn won the 2009 Nobel prize in physiology and medicine for co-discovering the enzyme telomerase. Telomerase catalyzes the replenishment of DNA stretches found at the ends of chromosomes called telomeres, which otherwise shorten whenever a cell divides. Telomere length is an indicator of systemic aging, with shorter lengths being associated with chronic diseases of aging and earlier mortality. I met with Professor Blackburn prior to the dialogue to discuss her work.

The Nobel worthy discovery and its implication

 

“It was pretty clear that right from the get go you needed something to maintain the ends of DNA.”

The Blackburn lab has sought to, and continues to seek, the full extent of a role telomerase and telomeres play in a cellular processed besides aging. “The credo of molecular biology tends to be that things are very universal in life and things are not going to be profoundly different. I sensed that this [finding] was going to be pretty fundamental. The question then was, we had no idea how this was going to play out in humans.” Today we know that telomere length underlies the proliferative capacity of a cell and telomere shortening, as a result of reduced telomerase activity with each cell division, is associated with the aging process and many age related diseases. However many factors besides aging can contribute to telomere maintenance such as chronic stress and lifestyle.

Health(y) behaviors and telomere maintenance

 

“Everybody has external stressors, there is nothing that can be done about this. It turns out that giving people tools to cope with these, when you look at people who have the ability to manage how they perceive stress, they do better in terms of their telomere maintenance.” Studies from the Blackburn lab and others focusing on the external factors which have an impact on telomere length show that engaging in, for example, mindfulness and healthy eating habits can have positive effects on telomeres; reducing the rate at which they shorten. These are early findings however provide insight into the sort of behaviors which possibly contribute to the aging process. “All that telomeres give us is a quantifiable, molecular, concrete readout that gives you some kind of a handle, statistically speaking, on [aging].”

Social reality and telomere maintenance

 

“[There has been] telomere research looking at people in chronic stressful life situations: those with socio-economic problems, people in war-torn countries, refugees… We see the effects of traumatic events on children relating to how short their telomeres are when they are middle aged. There are a lot of things we have to start thinking about.” A paper from the Blackburn lab looked the impact of discrimination and racial bias on telomere length in African-American men. Results suggested that “multiple levels of racism, including experiences of racial discrimination and the internalization of negative racial bias, operated together to accelerate biological aging among African-American men.” When discussing these findings Blackburn commented “…we all know that [these] social [attitudes] have ill effects; we know that this is not good for people and their health. But to see it hit people in this way, I think, well this is a way of making a message come through very clearly. We know concretely that this is happening. In so many ways it speaks to you.”

“We see the effects of traumatic events on children relating to how short their telomeres are when they are middle aged.”

Future

 

Future research into telomeres should study the molecular mechanisms which mediate changes in telomere length. “Part of my lab is [currently] focusing on trying to understand the very elaborate molecular ‘dance’ involving the telomere ends, telomerase and the telomere binding proteins. Really trying to elucidate all the molecular details.”

Should clinicians start monitoring patient telomere length? Blackburn notes that “monitoring [of telomere length] is like weighing; that single piece of information, is useless without context,” but along with patient data could, in the future, aid prognosis and provision of suitable care.

“A study looked at depression and its correlation with bladder cancer in a cohort of patients. They found that those with depression had almost two times the likelihood of dying from the cancer. [Later it was also found that] if their telomeres where in the lower portion of length distribution, in addition to being depressed, their odds of dying increased by 5 fold.”

The Blackburn lab are working hard to elucidate everything there is to know about telomeres and considering how critical this area of science is, I believe there is chance this lab will be recognized by the Nobel committee once more.

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