Epel E, Daubenmier J, Moskowitz JT, Folkman S, Blackburn E.
University of California San Francisco, Department of Psychiatry, San Francisco, California 94143, USA. firstname.lastname@example.org
Understanding the malleable determinants of cellular aging is critical to understanding human longevity. Telomeres may provide a pathway for exploring this question. Telomeres are the protective caps at the ends of chromosomes. The length of telomeres offers insight into mitotic cell and possibly organismal longevity. Telomere length has now been linked to chronic stress exposure and depression. This raises the question of mechanism: How might cellular aging be modulated by psychological functioning? We consider two psychological processes or states that are in opposition to one another-threat cognition and mindfulness-and their effects on cellular aging. Psychological stress cognitions, particularly appraisals of threat and ruminative thoughts, can lead to prolonged states of reactivity. In contrast, mindfulness meditation techniques appear to shift cognitive appraisals from threat to challenge, decrease ruminative thought, and reduce stress arousal. Mindfulness may also directly increase positive arousal states. We review data linking telomere length to cognitive stress and stress arousal and present new data linking cognitive appraisal to telomere length. Given the pattern of associations revealed so far, we propose that some forms of meditation may have salutary effects on telomere length by reducing cognitive stress and stress arousal and increasing positive states of mind and hormonal factors that may promote telomere maintenance. Aspects of this model are currently being tested in ongoing trials of mindfulness meditation…Summary and SignificanceStress cognitions are important for survival, but if they are based on distorted perceptions, they may promote excessive stress arousal, creating a harmful milieu for cellular longevity. During the longevity conference that these proceedings are based upon, H.H. the Dalai Lama explained that emotions based on reason and analysis, tend to drive meaningful behavior. In contrast, emotions based on ‘false projections’ or fear-based beliefs are harmful to longevity. Here, as shown in Figure 1, we speculate that certain types of meditation can increase awareness of present moment experience leading to positive cognitions, primarily by increasing meta-cognitive awareness of thought, a sense of control (and decreased need to control), and increased acceptance of emotional experience. These cognitive states and skills reduce cognitive stress and thus ability for more accurate appraisals, reducing exaggerated threat appraisals and rumination, and distress about distress. These positive states are thus stress-buffering. Increasing positive states and decreasing stress cognitions may in turn slow the rate of cellular aging.There is some indirect support of aspects of this hypothesis involving stress cognitions. In our previous study, perceived life stress — primarily an inability to cope with demands and feeling a lack of control, and higher nocturnal stress hormones (cortisol and catecholamines) were related to shorter telomere length.2 Trait negative mood was related to lower telomerase activity, a precursor of telomere shortening.144 Here we presented preliminary data from the same sample linking telomere length to higher proportions of challenge appraisals relative to threat appraisals in response to a standardized stressor. The results suggest that the relative balance of threat to challenge cognitions may be important in buffering against the long term wear and tear effects of stressors. To the extent that meditation mitigates stress-related cognitions and propagation of negative emotions and negative stress arousal, a longstanding practice of mindfulness or other forms of meditation may indeed decelerate cellular aging.We also speculate about the physiological mechanisms. Above we have reviewed data linking stress arousal and oxidative stress to telomere shortness. Meditative practices appear to improve the endocrine balance toward positive arousal (high DHEA, lower cortisol) and decrease oxidative stress. Thus, meditation practices may promote mitotic cell longevity both through decreasing stress hormones and oxidative stress and increasing hormones that may protect the telomere. There is much evidence of neuroendocrine and physical health benefits from TM, which has a longer history of study than MBSR. The newer studies of mindfulness meditation are promising, and offer insight into specific cognitive processes of how it may serve as an antidote to cognitive stress states.This field of stress induced cell aging is young, our model is highly speculative, and there are considerable gaps in our knowledge of the potential effects of meditation on cell aging. Several laboratories are working on diverse aspects of this model, which will soon allow it to be evaluated in light of the empirical data.
Source: Ann N Y Acad Sci. 2009 Aug;1172:34-53. doi: 10.1111/j.1749-6632.2009.04414.x
What is telomeres by Blackburn
“Think of telomeres as like the plastic tips that cap your shoelaces to prevent fraying, Telomeres allow cells to divide while holding the important genetic material intact. But now in your mind turn that shiny shoelace tip into wax, like a candle. It’s malleable – more like wax than a shiny plastic tip. It slowly burns down with age, getting shorter and shorter. Because every time cells divide, unless something intervenes, telomeres get progressively whittled down until, eventually, the cells die. So this candle length is a ‘fuse’ that determines the lifespan of cells – the fuse is the telomere and when it gets too short in cells, all hell breaks loose…”