Abstract: Objective: To investigate the therapeutic effects and mechanisms of Hedysari Polysaccharides (HPS) and Hedysari Polysaccharide HG-1 (HHG-1) on osteoarthritis (OA) of rats.Methods: Wistar rats were randomly divided into seven groups with eight in each as following:normal control group, model control group, positive control group(Sodium hyaluronate, SHA 1.00 mg/joint), HPS treated group (HPS 0.35 or 1.05 mg/join), and HHG-1 treated group(HHG-1 0.15 or 0.45 mg/joint). The rat's OA model was established with papain. The range of joint activity, synovial pathology and its glycosaminoglycan (GAG) content, whole blood viscosity, and serum antioxidant indexes were determined after treated with HPS and HHG-1.Results: HPS (0.35, 1.05 mg/joint) and HHG-1 (0.15, 0.45 mg/joint) could significantly enlarge the stretching angle of knee joint, relieve the pathological changes of articular cartilage, inhibit abnormal thickening of articular synovium, increase the content of GAG in synovi in the OA' rats. Meanwhile, HPS and HHG-1 could reduce the blood viscosity, enhance the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), decrease the serum level of malondialdehyde (MDA) (P<0.05, P<0.01).Conclusion: HPS and HHG-1 have some therapeutic effects on OA, but there is no significant difference between the two groups. Its possible mechanisms are improving hemorheology to alleviate abnormal cartilage metabolism and improving the activity of antioxidant enzymes to relieve cartilage injury.

Key words: hedysari polysaccharides (HPS), hedysari polysaccharide HG-1(HHG-1), osteoarthritis, blood viscosity, antioxidant system, rats