ENERGY RESTRICTION WITH HIGH-FAT DIET ENRICHED WITH COCONUT OIL GIVESHIGHER UCP1 AND LOWER WHITE FAT IN RATS

OBJECTIVE: To investigate the effects of overfeeding on a high fat die t, enriched in coconut oil, and the influence of food restriction on t he uncoupling protein (UCP1) expression and on body fat content. DESIG N AND SUBJECTS: In experiment I, female Wistar rats were fed ad libitu m either a normal-fat diet (control group, C) or a high-fat diet (HF), enriched in coconut oil, for 7 weeks. In experiment II, HF rats after finishing experiment I were fed (for 3 weeks) either the normal-fat d iet (group CAHF, Control After High Fat) or food restricted diets whic h provided 60% of the energy intake of group CAHF: a group fed a low-e nergy, normal-fat diet (LENF) and another fed a few-energy, high-fat d iet (LEHF), MEASUREMENTS: Body and fatty depot weights. Food intake. p rotein and UCP1 levels of interscapular brown adipose tissue. RESULTS: High-fat diet feeding promoted an increase in body fat content, body weight and UCP1 levels. Energy restriction induced similar body weight reduction in groups LENF and LEHF, However, some adipose depots were more strongly reduced in the rats fed the high-fat diet enriched in co conut oil (group LEHF) than in the rats fed the normal-fat diet (Group LENF), Specific UCP1 was 2.0 (group LENF) and 3.4 (group LEHF) times higher than in controls (group CAHF). CONCLUSION: The coconut-oil enri ched diet is effective in stimulating UCP1 expression during ad libitu m feeding and in preventing its down regulation during food restrictio n, and this goes hand in hand with a decrease of the white fat stores.