Improvement of high-fat diet-induced obesity by a mixture of red grape extract, soy isoflavone and l-carnitine: Implications in cardiovascular and non-alcoholic fatty liver diseases

In the present study, we examined the effect of a mixture of dietary components, including red grape extract, soy isoflavone and l-carnitine (RISC), on obesity. RISC substantially inhibited high-fat diet (HFD)-induced increase in body weight in a dose-dependent manner in C57BL/6 mice. The amount of subcutaneous and mesenteric fat was also significantly decreased by RISC treatment in HFD-fed C57BL/6 mice, whereas epididymal fat was not affected. Moreover, HFD-induced plasma leptin levels were down-regulated by RISC treatment. In these mice, RISC treatment significantly increased the plasma level of high density lipoprotein cholesterol without affecting the level of low density lipoprotein cholesterol and triglycerides. In addition, HFD-induced increase in liver weight and lipid accumulation in liver was significantly suppressed by RISC treatment in C57BL/6 mice. Plasma level of glutamic-oxaloacetic transaminase and glutamic-pyruvic transaminase was also inhibited by RISC treatment. These results demonstrate that RISC suppresses HFD-induced obesity and suggest that RISC supplementation might be a promising adjuvant therapy for the treatment of obesity and its complications, such as cardiovascular and non-alcoholic fatty liver diseases.