Translation of Stress Biology to the Human Condition

We live in an increasingly "stressed-out" world and an extension of the laboratory work on stress has been to apply knowledge of the neuroscience and neuroendocrinology of stress to the human condition via three outside activities. The first is the MacArthur Foundation Project on Socioeconomic Status and Health and the second and third are the National Council on the Developing Child along with the IOM Board on Children, Youth and Families.

Education and income and resulting socioeconomic status (SES) predict gradients of health in many societies. There are undoubtedly many mechanisms, but among the most prominent are the manifestations of physiological stress responses as a result of living and working conditions, inter-personal conflict, as well as the sense of control of one's environment and optimism/ pessimism toward the future. The gradient of income inequality plays a powerful role in these gradients of health (see Wilkinson The Spirit Level). "Allostatic load" refers to the cost of adaptation to a stressful environment, which elicits repeated and sometimes prolonged adaptive responses ("allostasis") that preserve homeostasis in the short run but can cause wear- and-tear on the body and brain. Decreased cognitive function during aging as well as abdominal obesity and increased risk for hypertension and cardiovascular disease, insulin-dependent diabetes and decreased immune responses are all manifestations of allostatic load. McEwen works collaboratively with physicians, sociologists, psychologists, anthropologists and economists in a network of the J.D. and C.T. MacArthur Foundation to begin to unravel the complexities of SES and health (see Reaching for a Better Life).

Concerning children and families, early life adversity has lasting effects on physical as well as mental health and on cognitive development and function. Efforts to improve the family environment will have huge benefits to society, both in terms of productivity and life-happiness and by reducing the financial burden on society for health care, incarceration and other human services Dr McEwen works with scientists from many disciplines of neuroscience, health psychology, pediatrics and medicine and with deliverers of human services to inform policy makers and the public about the best types of intervention, with emphasis on prevention.

At the same time, the McEwen lab collaborates on two projects that are relevant to brain development. The first, with Dr. Akaysha Tang of the University of New Mexico and Dr. Russ Romeo, Columbia University, is showing the benefits of brief exposure of newborn rat pups to novelty during their first weeks of life, resulting in enhanced social development and cognitive function. The second project, carried out in our laboratory by Dr. Lisa Eiland, neonatalogist at Weill Cornell, deals with the effects of separation of newborn pups from their mothers for several hours per day, as a model of the lasting effects of maternal separation in premature human infants in a neonatal intensive care unit. This is a collaboration with the laboratories of Huda Akil and Stan Watson at the University of Michigan. Thus far, she has found impairment of development of the hippocampus and potentiation of anxiety when these rats are stressed chronically as young adults. (See Effects of Stress on the Developing Brain).

Relevant Publications

  • McEwen, B.S. and Stellar, E. Stress and the Individual: Mechanisms leading to disease. Arch. Intern. Med. 153:2093-2101 (1993).
  • McEwen, B.S. Protective and damaging effects of stress mediators. New England J. Med. 338: 171-179 (1998).
  • Adler, N.E., Marmot, M., McEwen, B.S., and Stewart, J. (Eds.) Socioeconomic Status and Health in Industrial Nations: Social, Psychological, and Biological Pathways. Annals of the New York Academy of Sciences: New York, 1999.
  • McEwen, B.S. and Wingfield, J.C. The concept of allostasis in biology and biomedicine. Horm. & Behav. 43:2-15 (2003).
  • Akers, K.G., Yang, Z., DelVecchio, D.P., Reeb, B.C., Romeo, R.D., McEwen, B.S., and Tang, A.C. Social competitiveness and plasticity of neuroendocrine function in old age: influence of neonatal novelty exposure and maternal care reliability. PLoS ONE 3(7):e2840 (2008).
  • Shonkoff, J.P., Boyce, W.T., and McEwen, B.S. Neuroscience, molecular biology, and the childhood roots of health disparities. JAMA 301:2252-2259 (2009).
  • McEwen, B.S., and Gianaros, P.J. Central role of the brain in stress and adaptation: Links to socioeconomic status, health, and disease. Ann. N.Y. Acad. Sci. 1186:190-222 (2010).
  • Seeman, T., Epel, E., Gruenewald, T., Karlamangla, A., and McEwen, B.S. Socio-economic differentials in peripheral biology: Cumulative allostatic load. Ann. NY Acad. Sci. 1186:223-239 (2010).
  • Eiland, L. and McEwen, B.S. Early life stress followed by subsequent adult chronic stress potentiates anxiety and blunts hippocampal structural remodeling. Hippocampus (2011) in press.
  • McEwen, B.S. and Gianaros, P.J. Stress- and allostasis-induced brain plasticity. Annu. Rev. Med. 62:5.1-5.15 (2011).

Current Grant Support:

The Developmental Neurobiology of the Separation Distress Circuit in Rat:
Mechanisms of Vulnerability and Resilience (Hope for Depression Research Fdn.)