The work will help researchers study the role of psychosocial stress on cardiovascular disease and shortened lifespan in people.
Indiana Researchers have discovered that animals who became dominant in a social relationship lived significantly longer than those who became subordinate.
The study, in collaboration with the University of Minnesota, represents the first rodent model assessing the impact of chronic stress on the lifespan of mice, cellular aging and diseases associated with aging, such as atherosclerosis, or fatty deposits that can clog arteries.
Stress and socio-economic status has long been connected to death and disease in humans, but the mechanisms behind these processes have not been understood or fully explored in animal models until now.
“Our social environment, where we are in the dominance hierarchy of life, whether we feel down-trodden or empowered seem to have powerful relations with obesity, metabolic health, aging and lifespan,” said David Allison, dean and Provost Professor of the IU School of Public Health-Bloomington, who contributed to the study. “These research findings take us one step closer in understanding more about the socially influential aspects of stress on our health and longevity.”
The study, published recently in the journal Aging Cell, studied social stress by exposing male mice to one another in close proximity and then measuring their aggressive or submissive behaviors. Researchers found that lifelong stress was not only associated with a shortened lifespan, but an earlier onset of organ lesions and tumors, an associated rise cellular aging and a spontaneous onset of early-stage atherosclerosis.
The mice were studied in the laboratory of Alessandro Bartolomucci of the University of Minnesota Medical School.
“Paradoxically, this phenomenon has been known and established in many landmark studies about the negative impact of chronic stress and low socioeconomic status on human health,” Bartolomucci said. “But because this has never been replicated in any animal model, the mechanism of the association between stress, aging, and survival remains unclear. That’s where our study comes in.”
Part of a larger umbrella research project which ties together several hypotheses on energetics, disparities and lifespan, Allison hopes that these studies will not only increase understanding, but will also serve as an impetus to reduce disparities and inequities.
Additional authors are David Largaespada of the University of Minnesota; Chad Touma, of the University of Osnabruck in Germany; and Rupert Palme of the University of Veterinary Medicine in Austria.
This study was funded in part by a Transformative Research Award from the National Institutes of Health.