Western Diet (WD) and Ketogenic Diet (KD) Implication on Voluntary Wheel Running

Abstract

Physical inactivity is closely associated with a multitude of chronic diseases, which can lead to a poorer quality of life and premature death. The mesolimbic dopamine system has been shown to modulate motivation and reward pathways that drive physical activity. High fat diets (HFD) are known to alter pathways in the brain that drive physical inactivity. However, underlying mechanisms still need more exploration.ObjectiveThe purpose of my study was to exam HFD's lowering of physical activity.MethodsIn this study male and female Wister rats at 7 weeks of age 1) were placed into running wheels and 2) fed a ketogenic diet (KD), western diet (WD), or standard chow diet (SD) chronically for 7 weeks. Previous studies from the literature shows rats on a HFD tend to overeat leading to weight gain that may lead to decreased voluntary running. In order to measure physical activity independently of caloric intake, rats on the KD and WD were only allowed access to same amount of food calories consumed by the SD group.ResultsDespite giving equal caloric amounts, male rats on the KD had attenuated weight gain (p<0.001) compared to rats fed SD after the first week on the diet. Furthermore, female rats on the WD had increased weight gain in comparison to SD group (p<0.01) by week 7. Both male and female rats had a larger percentage body fat on either HFD compared to SD (p<0.01). Female rats on a WD had a significantly higher body fat percentage than female rats fed the KD (p<0.01). All these data suggest HFD's can change energy expenditure and this effect is gender specific. The results also showed gender specificity when looking at voluntary physical activity. Male rats fed either a KD or WD had overall increases in voluntary wheel running (p<0.05) compared to the SD group. Interestingly, female rats on either HFD showed no increase in running; with rats on a WD running significantly less than the SD group in week 7 (p< 0.01). Transcripts in the mesolimbic dopamine system are currently being analyzed.ConclusionHFD's alter voluntary running in a gender specific manner in which the male rats in the present study showed an increase in voluntary wheel running, while the females showed no increase in voluntary wheel running with a decrease in running towards the end of the study.SignificanceThe present study reveals HFD influences physical inactivity independently of caloric intake in a gender‐specific manner. This study provides novel insights on how to combat physical inactivity to increase quality and quantity of lifespan.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.