060. OVER FEEDING EARLY IN LIFE AND RISK OF OBESITY: INSIGHT FROM THE RODENT

Abstract

While adult lifestyle factors undoubtedly contribute to the incidence of obesity and its attendant disorders, mounting evidence suggests that programming of obesity may occur following over-nutrition during development. As hypothalamic control of appetite and energy expenditure is set early in life and can be perturbed by certain exposures such as under-nutrition and altered metabolic and hormonal signals, in utero exposure to maternal obesity related changes may contribute to programming of obesity in offspring. Data from animal studies indicate both intrauterine and postnatal environments are critical determinants of the development of pathways regulating energy homeostasis. Experimental evidence in rat studies from our laboratory points to an additive detrimental impact of high fat diet consumption after weaning in animals born of obese mothers. Deleterious effects of high fat diet during pregnancy on metabolic profile, adiposity and cardiac hypertrophy were enhanced by postnatal over consumption. Even modest early postnatal overfeeding induced by litter size reduction leads to increased adiposity. Studies are needed to determine to what extent the effect of maternal and early nutritional changes persist. This presentation summarizes recent evidence of the impact of maternal obesity on subsequent obesity risk, paying particular attention to the hypothalamic regulation of appetite, and markers of metabolic control. There is an urgent need to investigate the mechanisms underlying the trans-generational effects of maternal obesity due to an extraordinary rise in the rates of maternal obesity.