Rice bran oil reduces organ-specific fat deposition, attenuates hyperlipidaemia and abnormal liver function in Long Evans rats with high fat intake

Abstract

Introduction: High-calorie diets, particularly the quality of dietary fats, are regarded as an independent risk factor for developing obesity, hyperlipidaemia, and liver diseases. The present study examined the impact of rice bran oil (RBO) on organ-specific fat deposition, lipid profile, and liver function enzymes in Long Evans rats. Methods: Long Evans rats (n=24) were fed for six weeks with a controlled high-fat diet (HFD) to induce hyperlipidaemia and abnormal liver function. Rats were then divided into two groups: one group continued feeding on HFD, and the other group was fed with a RBO diet, replacing the fat source. After six weeks of feeding, six rats from each group were sacrificed and required analytical tests were performed. The remaining obese rats (n=12) were divided into continued HFD and RBO diet, and after sacrificing, essential analytical tests were done. Results: RBO feeding to hyperlipidaemic rats for six weeks significantly reduced brown adipose tissue, abdominal adipose tissue, epididymal adipose tissue, and liver fat compared to continuing HFD group (p<0.05). Similarly, serum levels of total cholesterol, triacylglycerides, and low-density lipoprotein cholesterol were all decreased, whereas high-density lipoprotein cholesterol increased in response to RBO compared to HFD (p<0.05). Additionally, rats fed with RBO showed reduced alanine aminotransferase, aspartate aminotransferase, and gamma-glutamyl transferase levels when compared with continuing HFD-fed rats (p<0.05). Conclusion: These findings suggest that RBO supports the reduction of fat storage from major fat depots, controls lipid profile, and restores healthy liver functions in rats.