Oxidative stress in osteoarthritis and antioxidant effect of polysaccharide from angelica sinensis

This study aimed to investigate the oxidative stress in human osteoarthritis (OA) chondrocytes and the antioxidant effect of angelica sinensis polysaccharide (ASP) on it. Human OA chondrocytes and human normal chondrocytes induced by hydrogen peroxide (H₂O₂) alone or treated with ASP were cultured, then they were measured with cell viability, levels of reactive oxygen species (ROS), nitric oxide (NO) and malondialdehyde (MDA) production, activities of inducible nitric oxide synthase (iNOS), superoxide dismutase (SOD) and catalase (CAT), expression of related genes, such as collagen type II (Col2a1), Aggrecan, iNOS, SOD, CAT and peroxisome proliferator-activated receptor gamma (PPARγ). We found that the production of ROS, NO, and MDA and the activity of iNOS, SOD and CAT were significantly increased in OA chondrocytes compared with human normal chondrocytes. When treated with H₂O₂, human chondrocytes exhibited acute oxidative stress injure, which was similar to OA chondrocytes. Pretreatment with ASP before H₂O₂ alleviated oxidative stress and protected human chondrocytes. The activity of PPARγ was decreased in OA chondrocytes and increased when treated with ASP. In conclusion, oxidative stress is an important pathogenesis of OA, and ASP inhibits H₂O₂-mediated injury in human chondrocytes. Our data also suggest that PPARγ participates in oxidation and anti-oxidation of OA.