Beneficial effect of dietary Ephedra sinica on obesity and glucose intolerance in high-fat diet-fed mice

Obesity is a major contributor to both glucose intolerance and metabolic syndrome. In this study, we investigated the anti-obesity and anti-hyperglycemic effects of Ephedra sinica on high-fat diet-fed mice. Male ICR mice were divided into four groups; the normal group, the obese and diabetic control group treated with a high-fat diet, the positive control group treated with a high-fat diet containing acarbose, and the experimental group treated with a high-fat diet containing Ephedra sinica. The effects of Ephedra sinica on obesity and glucose intolerance were measured by an oral glucose tolerance test (OGTT), plasma biochemistry, body and epididymal fat weight; the expression of adiponectin, peroxisome-proliferator-activated receptor alpha (PPAR-alpha), tumor necrosis factor alpha (TNF-alpha) and leptin was also determined. Ephedra sinica reduced weight gain and epididymal fat accumulation, improved glucose intolerance on the OGTT, decreased triglycerides and increased high-density lipoprotein cholesterol compared to the controls. Moreover, it reduced weight gain and fasting glucose levels and improved HDL-cholesterol levels more than acarbose. Gene expression analysis revealed that Ephedra sinica upregulated the expression of adiponectin and PPAR-alpha, and downregulated the expression of TNF-alpha. From these results, we suggest that Ephedra sinica may reduce obesity and hyperglycemia by increasing PPAR-alpha and adiponectin and reducing TNF-alpha, and that it may have the potential to be used clinically as an ingredient in food or drugs effective in obesity-related glucose intolerance treatments.