Effect of different dietary saturated fats on plasma lipid levels and adipose tissue lipoprotein lipase in rats

Abstract The metabolic effects of feeding diets containing different sources of saturated fats on plasma lipid levels were studied in rats. Twenty four male Sprague Dawley rats were divided into three groups with average weight of 268.43±3.46 (g±SE). Rats were fed diets containing 50% of dietary calories from butter (B), cocoa butter (CB) and coconut oil (CO). During the last 3 days of the 7 week adlibitum feeding period fecal fat was measured. After a 12 hour fast, the rats were sacrificed and blood samples were analyzed for serum triglycerides, total and HDL cholesterol and Insulin. Samples from the right epididymal fat pad were assayed for adipose tissue Lipoprotein Lipase activity (AT-LPLA). Adipocyte size also was measured. Results showed that CO fed rats gained more weight and deposited more fat than CB or B.fed rats. Percent fat absorption was significantly lower in CB than either CO or B fed rats. Carcass analysis showed that total dissectible fat, percent body fat and adipocyte size were significantly greater in CO than CB fed rats. CO fed rats maintained higher HDL cholesterol levels than CB fed rats. AT-LPLA per fat cell did not differ between the three groups of rats. We conclude that coconut oil raises HDL-C levels when it replaces B or CB. This effect is not mediated by AT-LPLA