Effects of Exercise Ancestry on Multiple Generations of Mature C57BL/6 Mouse Offspring

Abstract

The objective was to examine if exercise (EX) ancestry vs. sedentary (SED) ancestry alters body/tissue mass, glucose metabolism, or muscle mRNA in two generations of mature mouse offspring. C57BL/6 mice (F0) were exposed to EX (wheel running, N=20) or a SED condition (no wheel, N=20) for 12 weeks before breeding. EX males bred with EX females and SED males bred with SED females to obtain F1 pups. F0 EX animals had wheel access through weaning. F1 pups bred with like‐ancestry F1 offspring to obtain the F2 pups. F1 and F2 offspring were sacrificed at 28 wk without EX exposure. Body and tissue masses were recorded, intraperitoneal glucose tolerance was measured, and mRNA expression of several metabolic genes was examined in muscle. In F1 males, liver and soleus mass were lower in EX (p < 0.05). F2 EX males also had lower liver and soleus masses (p < 0.05). In females, no differences in tissue mass were observed. However, F1 EX females had higher baseline glucose (p < 0.05) while F2 SED females had better glucose tolerance (p < 0.05). No differences in glucose or glucose tolerance were observed in male offspring. Pgc1a mRNA expression was higher in F1 EX males and Cox1 mRNA expression was higher in F2 SED males. There were no other differences in mRNA expression. These findings suggest limited, generation‐ and sex‐specific effects of EX ancestry on tissue mass, glucose metabolism, and muscle mRNA in two generations of mature C57BL/6 offspring.This work was supported by NIH grants HD062868 and AG000268.