As I continue to read and re-read parts of the article on the research of Elizabeth Blackburn, I get more and more amazed. This is intense, groundbreaking research on how stress ages us. Here’s the basic piece: she and her fellow researchers found:
… a repeating DNA motif that acts as a protective cap [on chromosomes]. The caps, dubbed telomeres, were subsequently found on human chromosomes too. They shield the ends of our chromosomes each time our cells divide and the DNA is copied, but they wear down with each division. In the 1980s, working with graduate student Carol Greider at the University of California, Berkeley, Blackburn discovered an enzyme called telomerase that can protect and rebuild telomeres. Even so, our telomeres dwindle over time. And when they get too short, our cells start to malfunction and lose their ability to divide – a phenomenon that is now recognised as a key process in ageing. This work ultimately won Blackburn the 2009 Nobel Prize in Physiology or Medicine.
Then she connected with Elissa Epel, a postdoc from UCSF’s psychiatry department, and the two began working on taking this research into the real world. They did research on mothers, and the findings are powerful:
The results were crystal clear. The more stressed the mothers said they were, the shorter their telomeres and the lower their levels of telomerase.
The most frazzled women in the study had telomeres that translated into an extra decade or so of ageing compared to those who were least stressed, while their telomerase levels were halved. “I was thrilled,” says Blackburn. She and Epel had connected real lives and experiences to the molecular mechanics inside cells. It was the first indication that feeling stressed doesn’t just damage our health – it literally ages us.
Ten years of research since then has added lots to the picture.
“Ten years on, there’s no question in my mind that the environment has some consequence on telomere length,” says Mary Armanios, a clinician and geneticist at Johns Hopkins School of Medicine who studies telomere disorders.
There is also progress towards a mechanism. Lab studies show that the stress hormone cortisol reduces the activity of telomerase, while oxidative stress and inflammation – the physiological fallout of psychological stress – appear to erode telomeres directly.
This seems to have devastating consequences for our health. Age-related conditions from osteoarthritis, diabetes and obesity to heart disease, Alzheimer’s and stroke have all been linked to short telomeres.
The big question for researchers now is whether telomeres are simply a harmless marker of age-related damage (like grey hair, say) or themselves play a role in causing the health problems that plague us as we age.
…This much we know; telomeres tend to shorten over time. But at age 75–80, the curve swings back up as people with shorter telomeres die off – proof that those with longer telomeres really do live longer. “It’s lovely,” she says. “No one has ever seen that.”
But the most interesting part of the studies to me – and I think I’ve blogged this bit before – is that meditation can help. They have begun researching
… ways to protect telomeres from the effects of stress; trials suggest that exercise, eating healthily and social support all help. But one of the most effective interventions, apparently capable of slowing the erosion of telomeres – and perhaps even lengthening them again – is meditation.
And this bit sounds like a quote from a mindfulness meditation manual:
Theories differ as to how meditation might boost telomeres and telomerase, but most likely it reduces stress. The practice involves slow, regular breathing, which may relax us physically by calming the fight-or-flight response. It probably has a psychological stress-busting effect too. Being able to step back from negative or stressful thoughts may allow us to realise that these are not necessarily accurate reflections of reality but passing, ephemeral events. It also helps us to appreciate the present instead of continually worrying about the past or planning for the future.
… That study, of 239 healthy women, found that those whose minds wandered less – the main aim of mindfulness meditation – had significantly longer telomeres than those whose thoughts ran amok. “Although we report merely an association here, it is possible that greater presence of mind promotes a healthy biochemical milieu and, in turn, cell longevity,” the researchers concluded. Contemplative traditions from Buddhism to Taoism believe that presence of mind promotes health and longevity; Blackburn and her colleagues now suggest that the ancient wisdom might be right.