Metabolic and endocrine consequences of social stress in a visible burrow system

109

163

Individuals vary substantially in their vulnerability to physical and psychosocial stressors. The causes of such variation in susceptibility to stress are poorly understood, but are thought to relate in part to genetic factors. The present study evaluated the extent to which polymorphisms in the gene encoding the serotonin reuptake transporter (5HTTLPR or SERT) modulated physiologic responses to the imposition of psychosocial stress (social reorganization and subordinate social status) in female rhesus monkeys. Forty females, drawn from the middle ranking genealogies of several large social groups, were reorganized into eight groups containing 5 monkeys each; four groups were comprised entirely of animals homogeneous for the long promoter variant in the SERT gene (l/l), while the other four groups had monkeys with at least one allele of the short promoter variant (l/s or s/s). Females were sequentially introduced into these new groups in random order and dominance ranks were established within several days. During the ensuing 6 weeks, dominant monkeys exhibited elevated rates of aggression while subordinates displayed high rates of submission. Notably, females with the s-variant SERT genotype, collapsed across social status positions, exhibited the highest overall rates of both aggression and submission. Although neither social status nor SERT genotype influenced morning cortisol concentrations, glucocorticoid negative feedback was reduced significantly in subordinate compared to dominant females irrespective of genotype. All animals lost weight and abdominal fat across the experiment. However, decreases were greatest in subordinates, regardless of genotype, and least in dominant females with the l/l genotype. Serum concentrations of insulin, glucose, and ghrelin decreased significantly during the group formation process, effects that were independent of genotype or social status. In contrast, social status and genotype interacted to influence changes in serum concentrations of leptin and triiodothyronine (T3), as dominant, l/l females had the highest levels while subordinate s-variant females had the lowest levels. The order in which a female was introduced to her group generally predicted her eventual social rank. However, rank was additionally predicted by pre-experimental T3 and abdominal fat values, but only in the l/l animals. While these findings must be replicated with a larger sample size, the data suggest that the s-variant SERT genotype confers increased vulnerability to the adverse effects of psychosocial stress associated with subordinate status while the l/l genotype benefits the most from the absence of stress conferred by dominant social status. These findings suggest that genetic factors modify the responses of monkeys to social subordination and perhaps other psychosocial stressors.

Section: Discussionsupporting

confidence: 69%

Section: Discussionmentioning

confidence: 80%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Polymorphisms in the serotonin reuptake transporter gene modify the consequences of social status on metabolic health in female rhesus monkeys

Jarrell¹,

Hoffman²,

Kaplan³

et al. 2008

109

163

“…More recently, we have used the VBS model to examine the effects of social dominance and subordination on the neuroendocrine systems regulating the stress response, reproduction and energy homeostasis [10,24,[27][28][29]. The housing environment in the VBS closely represents the conditions under which rats would live in the wild and serves to facilitate expression of behavioral and physiological responses that would normally occur in that environment.…”

Section: The Visible Burrow System (Vbs) Model Of Social Stressmentioning

confidence: 99%

Dynamic body weight and body composition changes in response to subordination stress

Tamashiro

Hegeman

Nguyen

et al. 2007

Self Cite

101

Social stress is prevalent in many facets of modern society. Epidemiological data suggest that stress is linked to the development of overweight, obesity and metabolic disease. Although there are strong associations between the incidence of obesity with stress and elevated levels of hormones such as cortisol, there are limited animal models to allow investigation of the etiology of increased adiposity resulting from exposure to stress. Perhaps more importantly, an animal model that mirrors the consequences of stress in humans will provide a vehicle to develop rational clinical therapy to treat or prevent adverse outcomes from exposure to chronic social stress. In the visible burrow system (VBS) model of chronic social stress mixed gender colonies are housed for 2 week periods during which male rats of the colony quickly develop a dominance hierarchy. We found that social stress has significant effects on body weight and body composition such that subordinate rats progressively develop characteristics of obesity that occurs, in part, through neuroendocrine alterations and changes in food intake amount. Although SUB are hyperphagic following social stress they do not increase their intake of sucrose solution as CON and DOM do suggesting that they are anhedonic. Consumption of a high fat diet does not appear to affect development of a social hierarchy and appears to enhance the effect that chronic stress has on body composition. The visible burrow system (VBS) model of social stress may be a potential laboratory model for studying stress-associated metabolic disease, including the metabolic syndrome.

“…Visible burrow system: The structure and procedures of the VBS have been previously described [17][18][19][20][21][22][23]. The colonies were set-up such that each colony contained 4 females and 2 weight matched males: 1 proactive coping male rat and 1 passive coping male rat.…”

Section: Elevated Plus Maze Testmentioning

confidence: 99%

Stress coping style does not determine social status, but influences the consequences of social subordination stress

Boersma

Smeltzer

Scott

et al. 2017

Self Cite

Access to the full text of the published version may require a subscription. This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. Rights A C C E P T E D M A N U S C R I P T ACCEPTED MANUSCRIPTA C C E P T E D M A N U S C R I P T 2 Abstract: