Hypolipidemic and anti-atherosclerogenic effect of Glycyrrhiza glabra root extract in high fat diet induced hypercholesterolemic rats

Hyperlipidemia and oxidative stress are major risk factors for atherosclerosis, and all three are among the most important risk factors for cardiovascular diseases Glycyrrhiza glabra root extract has been used in Indian traditional medicine for the treatment of hypertension and associated cardiovascular diseases. This study was undertaken to evaluate the hypolipidemic and anti-atherosclerotic properties of the Glycyrrhiza glabra root extract in rats with hypercholesterolemia (HC). Sixty Normocholesterolemic (NC) male rats were divided into six groups and fed a high-cholesterol (HC) diet for 40 days (5 groups), or normal rat chow (normal control group). The plant extract was administered to animals at the increasing dose of 200, 300 and 400 mg/kg. After 4 weeks of treatment 3 rats out of 4 were sacrificed, blood samples, aorta, liver, and fresh faecal were collected and processed for biochemical tests. The experiments were conducted under the same conditions with a group of rat treated with atorvastatin (1 mg/kg), used positive control. The effects of Glycyrrhiza glabra root extract on weight gain, water and food consumptions, levels of serum lipids and lipoprotein lipid oxidation and stress markers in blood and liver were also examined. A significant body weight gain was observed in general in all the group of animals without any treatment after 4 weeks. During the treatment period, the Glycyrrhiza glabra root extract induced a significant increase (p < 0.01) in water consumption and food intakes. After 6 weeks of treatment with hypercholesterolemia, the body temperature and organ weights including the liver, kidney, heart and the testis did not present any significant change. The administration of Glycyrrhiza glabra root extract significantly (p < 0.05) prevented the elevation in TC, LDL-C, VLDL-C, hepatic and aortic TG and TC. The atherogenic, triglycerides, and lipid peroxidation (TBARS) index were also decreased in the rats treated with the plant extract. Glycyrrhiza glabra root extract favoured the performance of faecal cholesterol. It also significantly inhibited the changes and the formation of aortic atherosclerotic plaques. The results support the traditional use of the extract of this plant in the treatment of hypertension and diabetes.