SummaryStress and low socioeconomic status in humans confer increased vulnerability to morbidity and mortality. However, this association is not mechanistically understood nor has its causation been explored in animal models thus far. Recently, cellular senescence has been suggested as a potential mechanism linking lifelong stress to age‐related diseases and shorter life expectancy in humans. Here, we established a causal role for lifelong social stress on shortening lifespan and increasing the risk of cardiovascular disease in mice. Specifically, we developed a lifelong chronic psychosocial stress model in which male mouse aggressive behavior is used to study the impact of negative social confrontations on healthspan and lifespan. C57BL/6J mice identified through unbiased cluster analysis for receiving high while exhibiting low aggression, or identified as subordinate based on an ethologic criterion, had lower median and maximal lifespan, and developed earlier onset of several organ pathologies in the presence of a cellular senescence signature. Critically, subordinate mice developed spontaneous early‐stage atherosclerotic lesions of the aortic sinuses characterized by significant immune cells infiltration and sporadic rupture and calcification, none of which was found in dominant subjects. In conclusion, we present here the first rodent model to study and mechanistically dissect the impact of chronic stress on lifespan and disease of aging. These data highlight a conserved role for social stress and low social status on shortening lifespan and increasing the risk of cardiovascular disease in mammals and identify a potential mechanistic link for this complex phenomenon.

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Genetic predisposition and environmental challenges interact to determine individual vulnerability to obesity and type 2 diabetes. We previously established a mouse model of chronic subordination stress-induced hyperphagia, obesity, metabolic like-syndrome and insulin resistance in the presence of a high-fat diet. However, it remains to be established if social stress could also aggravate glucose intolerance in subjects genetically predisposed to develop obesity and type 2 diabetes. To answer this question, we subjected genetically obese mice due to deficiency of the leptin receptor (db/db strain) to chronic subordination stress. Over five weeks, subordination stress in db/db mice led to persistent hyperphagia, hyperglycemia and exacerbated glucose intolerance altogether suggestive of an aggravated disorder when compared to controls. On the contrary, body weight and fat mass were similarly affected in stressed and control mice likely due to the hyperactivity shown by subordinate mice. Stressed db/db mice also showed increased plasma inflammatory markers. Altogether our results suggest that chronic stress can aggravate glucose intolerance but not obesity in genetically predisposed subjects on the basis of a disrupted leptin circuitry.