Early nutritional changes induce sexually dimorphic long-term effects on body weight gain and the response to sucrose intake in adult rats.

Long-term metabolic effects induced by early nutritional changes are suspected to differ between males and females, but few studies have analyzed both sexes simultaneously. We analyzed the consequences of neonatal nutritional changes on body weight (BW) and the adult response to a sucrose-enriched diet in both male and female rats. Litter size was manipulated at birth to induce over- and undernutrition (4 pups: L4; 12 pups: L12; 20 pups: L20). From 50 to 65 days of age, half of each group received a 33% sucrose solution instead of water. Serum leptin, insulin, and ghrelin levels were analyzed at day 65. At weaning, rats from L4 weighed more and those from L20 weighed less than controls (L12). Body weight was greater in L4 rats throughout the study and increased further compared with controls in adult life. L20 males ate less and gained less weight throughout the study, but L20 females had a significant catch-up in BW. Sucrose intake increased total energy consumption in all groups, but not BW gain, with L4 males and L4 and L20 females reducing weight gain. Yet, sucrose intake increased serum leptin levels, with this increase being significant in L4 and L20 males. Our results suggest that females are more capable than males of recuperating and maintaining a normal BW after reduced neonatal nutrition. Furthermore, increased sucrose intake does not increase BW, but could alter body composition as reflected by leptin levels, with the percentage of calories consumed in the form of sucrose being affected by sex and neonatal nutrition.