Antihyperglycemic activity of Anoectochilus roxburghii polysaccharose in diabetic mice induced by high-fat diet and streptozotocin

Ethnopharmacological relevance: Anoectochilus roxburghii is a traditional Chinese herb used for treatment of diabetes and some other diseases. Anoectochilus roxburghii polysaccharose (ARP) is the main constituent of Anoectochilus roxburghii. The present study aimed to investigate the antidiabetic effects of ARP in diabetic mice induced by high-fat diet and streptozotocin. Materials and methods: Two doses of ARP (100 or 300 mg/kg) were administered once daily for 25 days to diabetic mice. To evaluate the antidiabetic effects of ARP, the fasting glucose levels, aspartate aminotransferase (AST), alanine transaminase (ALT) and superoxide dismutase (SOD) activities, malondialdehyde (MDA) content, triglyceride (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C) and liver glycogen were examined. Furthermore, histological examinations were carried out on the separated pancreas and liver of mice. Results: Compared with untreated diabetic mice, ARP (100 or 300 mg/kg) caused a significant decrease in blood glucose levels, activities of AST and ALT, and MDA contents, and a significant increase in liver glycogen contents, SOD activities, thymus index and spleen index. Simultaneously, the alteration in lipid metabolism was partially attenuated as evidenced by decreased serum TC, TG and LDL-C concentrations in diabetic mice. In addition, histological examinations showed that administration of ARP (100 or 300 mg/kg) significantly attenuated the pathologic lesions in pancreas and liver of diabetic mice, and improved pancreas and liver function. Conclusions: The antidiabetic activity of ARP may be attributed to the improvement of glucose and lipid metabolism, increase of immune protection and reduction of oxidative stress. (C) 2015 Elsevier Ireland Ltd. All rights reserved.