Negative predictive adaptive response of a high protein weaning diet in rats exposed to a high fat/sugar diet in adulthood

Strong evidence suggests that the risk of developing diseases such as type 2 diabetes and obesity may be programmed by early environmental influences. Dietary factors may specifically influence the programming of glucose and lipid metabolism. The aim was to examine the long‐term effects of early postnatal dietary programming by diets high in protein and fiber on lipid and glucose metabolism in adulthood. Wistar dams were mated and given free access to standard chow and water. At parturition, litters were culled to 10 pups. Pups were weaned at 21 days onto control or a diet high in protein (40%) or fiber (30%) and consumed these diets until adulthood (4 months). Rats were then challenged with a high fat/high sugar diet for 6 weeks. At the end of this period body composition was assessed and an oral glucose tolerance test (OGGT) performed. Organs were removed for mRNA analysis and blood drawn for analysis of satiety hormones. A long‐term high protein diet, when followed by one high in fat and sugar, resulted in significantly higher body fat percentage. Area under the glucose curve during OGTT was approximately 56% higher in protein fed rats. The protein diet also resulted in significantly lower levels of cholesterol 7‐α hydroxylase, sodium linked transporter‐1 and glucose transporter‐5 mRNA. This suggests that a long‐term diet high in protein may have negative consequences if it is not matched by subsequent adult diet. CIHR, NSERC