Maternal exercise is associated with a shift in adiposity distribution and improved markers of adipose health in offspring in mice

Abstract Introduction Sedentary (SED) behavior is highly prevalent during pregnancy and is linked to negative maternal and fetal metabolic outcomes, even independent of weight gain and obesity. While emerging evidence suggests that increased maternal physical activity can counteract the detrimental effects of maternal SED behavior on offspring metabolic health, the time course and tissue‐specific mechanisms involved remain poorly understood. Thus, this exploratory study assessed offspring metabolic health during adolescent and early adult stages according to maternal voluntary exercise status and examined potential sex differences and adipose markers. Methods Female C57BL/6J breeder mice were randomly assigned to SED or exercise (EX) groups, with voluntary wheel running beginning 2 weeks before breeding and continuing throughout pregnancy. Male and female offspring from SED and EX dams ( n = 11–15 per group) were assessed at 6 and 12 weeks of age for differences in body composition and glucose homeostasis. At 16 weeks of age, body composition was reassessed, and adipose depots were collected to assess for inflammation and fibroblast growth factor signaling markers. Results Voluntary exercise was not associated with differences in measures of maternal stress, including body mass throughout the study period, pregnancy rate, or litter size. There were no differences in overall body composition or glucose homeostasis at either adolescent or early adult time points between male and female offspring from SED versus EX mothers. Despite this, maternal exercise was associated with a shift in the adipose tissue distribution in offspring of both sexes away from subcutaneous white adipose tissue (% body mass: 1.25 ± 0.09 male SED vs. 0.87 ± 0.06 male EX vs. 1.15 ± 0.11 female SED vs. 0.95 ± 0.04 female EX; p Ex = 0.001, p Sex = 0.871, p Int = 0.236, two‐way ANOVA) toward brown adipose tissue (% body mass: 0.31 ± 0.03 male SED vs. 0.47 ± 0.05 male EX vs. 0.27 ± 0.02 female SED vs. 0.48 ± 0.05 female EX; p Ex = 0.001, p Sex = 0.704, p Int = 0.527). This shift was accompanied by lower expression of cytokines and higher expression of protective fibroblast growth factor receptors in adipose tissue. Conclusions These findings suggest that maternal exercise is associated with a shift in the adiposity distribution toward metabolically protective brown adipose tissue as well as improvements in markers of adipose metabolic health in offspring at adolescent and early adult stages. Additional research is needed to assess these adipose mechanisms over the lifespan and in response to metabolic challenges.