Effects of Conjugated Linoleic Acid on Lipid Accumulation and Intestinal Microbiota in Obese Rats Induced by High-fat Diet

Objective: To investigate the effects of conjugated linoleic acid (CLA) on lipid accumulation and intestinal microbiota in obese rats. Methods: Forty SPF male SD rats were randomly divided into four groups according to body weight, 10 rats in each group. The ND group was fed with ordinary diet, and the other groups were fed with high-fat diet. Among them, the ND group was intragastrically administered with peanut oil 1 g/kg, the model group (HD group) was intragastrically administered with peanut oil 1 g/kg, the low-dose group (LC group) was intragastrically administered with 0.2% conjugated linoleic acid 1 g/kg, and the high-dose group (HC group) was intragastrically administered with 2% conjugated linoleic acid 1 g/kg for 9 weeks of intervention. Bacterial DNA was extracted from feces of mice after collection of feces at the end of the experiment followed by 16S rDNA sequencing, after which blood was collected and sacrificed under anesthesia, and organ and visceral fat were taken and stored at −80 ℃. Results: The body weight, visceral fat, serum and liver triglycerides and total cholesterol of rats in the HD group were significantly higher than those in the ND group (P<0.05), and high-dose CLA intervention could significantly reduce the body weight, serum triglycerides, total cholesterol and liver total cholesterol of rats (P<0.05). High-fat diet could increase the relative abundance of Eubacterium_coprostanoligenes_group, Psychrobacter, Corynebacterium_1 and Staphylococcus in the intestinal microbiota level of rats. High-dose CLA could change the composition of intestinal microbiota in obese rats, such as significantly increasing the relative abundance of Bifidobacterium, Butyrivibrio and Ruminococcaceae_UCG-014 at the genus level (P<0.05) and reducing the relative abundance of Staphylococcus and Corynebacterium_1 (P<0.05). Conclusion: Conjugated linoleic acid could reduce body weight and lipid accumulation of obese rats induced by high fat diet, which might be related to the regulation of intestinal microbiotal diversity.