Environmental Endocrine Disruptor Affects Voluntary Physical Activity in Mice.

INTRODUCTION: Voluntary physical activity levels are regulated by sex hormones. The purpose of this study was to determine the effect of the endocrine disruptor benzyl butyl phthalate (BBP) on the regulation of physical activity in mice. METHODS: Mouse dams were treated with 500 mg[BULLET OPERATOR]kg-1[BULLET OPERATOR]day-1 of BBP or vehicle on gestation days 9-16. Pups were weaned and analyzed for voluntary physical activity levels, puberty development, sex hormone levels, and body composition over a 20 week period. RESULTS: Seventy-three offspring from BBP treated dams were studied (n=43 males, n=30 females). Endocrine disruption was indicated by decreased anogenital distances in BBP-treated male offspring at 10 (p=0.001) and 20 weeks (p=0.038) and delayed vaginal openings in BBP-treated female offspring (p=0.001). Further, there was a significant decrease in serum testosterone concentration in male mice between control and BBP at 10 weeks (p=0.039) and at 20 weeks (p=0.022). In female mice there was a significant increase in serum testosterone concentration in BBP mice at 20 weeks (p=0.002), and a significant increase in estrogen (estradiol) concentrations at 20 weeks in the control female mice (p=0.015). Overall, BBP mice ran significantly less distance (males, p=0.008; females, p=0.042) than controls. Other than a significant increase in BBP-treated males in fat mass at 20 weeks (p=0.040), there was no significant decrease in weight, lean mass, or fat mass in either female or male mice, regardless of treatment. CONCLUSION: Maternal endocrine disruption altered hormone response, but not body composition in either sex of offspring, with a corresponding decreased activity throughout early adulthood in all offspring. These results suggest that exposure to common environmental endocrine disruptors in utero, can reduce and alter physical activity levels in offspring. (C) 2016 American College of Sports Medicine

from Sports Medicine via xlomafota13 on Inoreader http://ift.tt/1UdLbqk
via IFTTT