Hypolipidemic and Antioxidant Effects of Malus toringoides (Rehd.) Hughes Leaves in High-Fat-Diet-Induced Hyperlipidemic Rats

Malus toringoides (Rehd.) Hughes (MT) leaves are traditionally used as a medicine for treating or preventing cardiovascular disease in Tibet. In addition to the effect of this medicinal plant on thrombosis, we tested its effect on dyslipidemia in a hypolipidemic rat model. A total of 60 healthy Sprague-Dawley rats were randomly divided into six groups, as follows: normal control, model control, simvastatin groups, and MT low-, medium-, and high-dose groups. The normal controls were fed with a normal diet, whereas all other groups were fed with a high-fat diet. After 6 weeks, the high-fat diet had induced hyperlipidemia in the rats, which were then orally administered with different doses of MT leaf extract (50, 100, and 200 mg/ kg) for an additional 6 weeks. Serum levels of total cholesterol (TC), triglycerides (TG), low-and high-density lipoprotein cholesterol (LDL-c and HDL-c, respectively), as well as the antioxidant capacity of glutathione peroxidase (GSHP-x), superoxide dismutase (SOD), and malondialdehyde (MDA) were measured at the end of the study. MT significantly reduced serum TC, TG, and LDL-c and increased the HDL-c content in MT-treated rats compared with the model group. These changes were dose dependent. MT treatment also significantly elevated the activity of SOD and GSHP-x, and decreased the serum levels of MDA compared with untreated hyperlipidemic rats, thereby increasing serum antioxidant capacity. In addition, MT reduced liver steatosis in hyperlipidemic rats. Overall, MT exerts considerable hypolipidemic and antioxidant properties.