Fig. 1.

Effect of social stress on metabolic parameters. Eight-week-old C57BL/6 male mice were subjected to CSDS (n = 14) or nonaggressive encounters (control, n = 14) and then randomized into groups receiving either chow or high-fat diet for 30 days. CSDS alters (A) social avoidance at day 11 and (B) body weight change at day 40. A subgroup of animals (n = 6/group) were further analyzed for (C) food intake, (D) body composition, (E) total cholesterol, (F) non–HDL cholesterol, (G) nonesterified fatty acids, (H) glucose, and (I) insulin. Data are presented as mean ± SEM, with significant differences as an insert on the chart (P < 0.05, P < 0.01, P < 0.001). Groups first tested by two-way ANOVA. If a statistical interaction was observed between factors, comparison of all four groups was performed by one-way ANOVA with Tukey posthoc comparison, and statistically different groups are indicated by different letters. CSDS, chronic social defeat stress; HFD, high-fat diet.