Effect of a lipid-enriched diet on body composition and some regulatory hormones of food intake in growing rats

Abstract

Objective The aim of the present study was to investigate the effects of a lipid-enriched diet on body composition and on main regulatory hormones of food intake (insulin, adiponectin, leptin, ghrelin). Method Two groups of 16 rats, 35 days old, weighing 80 ± 6 g, were constituted. One group (S) was given a standard diet during 10 weeks and served as control. The second group (L) was given a lipidic-enriched diet (containing: G: 41.5, L: 38.5, P: 20% calorie). Food and water were given “ad libitum”. Results Total food intake, body weight, skeletal area and lean body mass of rats eating lipid-enriched diet were lowered (6694 ± 178 vs. 8160 ± 184 kcal, P = 0.01; 431 ± 38 vs. 468 ± 25 g, P = 0.003; 72.19 ± 0.96 vs. 76.07 ± 1.31 cm 2, P = 0.03; 369 ± 18 vs. 409 ± 23 g, P = 0.0006), fat mass difference was not statistically significant (82.5 ± 17 vs. 80 ± 17 g, P = 0.7). Blood ghrelin, adiponectin levels were lowered (1517 ± 224 vs. 1915 ± 579 pg/ml, P = 0.03; 10 ± 3 vs. 19 ± 3 μg/ml, P = 0.003) whereas insulin and leptin were unchanged (1.8 ± 1.5 vs. 2.6 ± 1.4 ng/ml, P = 0.1; 16 ± 11 vs. 13 ± 10 ng/ml, P = 0.4). Conclusion A period of high fat diet in growing rats leads to a hypophagia, resulting in a lower lean body mass development. Some regulatory hormones of food intake did not change, while others significantly decreased, notably ghrelin being possible causal factor of the observed hypophagia linked to high fat diet.