The Effect of Early Life Undernutrition on Voluntary Physical Activity in Mice.

Abstract

Regular physical activity reduces the risk of cardiovascular disease, Type II diabetes, and metabolic syndrome. Perinatal undernutrition has been shown to program the development of chronic disease. PURPOSE: To determine if early life undernutrition influenced frequency and duration of wheel running (measure of physical activity) in mice during adulthood. METHODS: Using a cross-fostering model, pups were undernourished during gestation (GUN, N= 8) or during lactation (PUN, N= 8) by feeding FVB mothers a low protein diet (8% protein) causing growth restriction. The control group (CON, N= 7) was fed a normal protein diet (20% protein) throughout gestation and lactation. At 21 days of age, all pups were weaned and fed a control diet. At PN45, mice were then individually housed in cages with free-moving running wheels which recorded number of spins per day (Columbus Instruments). Average spins per day were calculated on days 5 and 6 for three weeks, and a two-way ANOVA was run comparing the main effects of diet and gender on average wheel spins. RESULTS: There was a significant difference between GUN mice (29535.625 ± 296 spins·day-1), CON (22988.7 ± 296 spins·day-1) and PUN (19667.5 ± 274 spins·day-1) (p<0.05). There were no significant differences between male and female groups. CONCLUSIONS: Based on the data, postnatal undernutrition elicits an impairment in physical activity engagement. Thus, the developmental processes that occur during this time period are suspected to program adult physical activity level.