title: Protective effect of sinomenine on cartilage degradation and chondrocytes apoptosis.
abstract: Sinomenine (SIN), an alkaloid extracted from the stem of the Chinese medicinal plant sinomenium acutum, has been used for treating rheumatoid arthritis. But little is known whether SIN has a protective effect on osteoarthritis (OA). In this study, we investigated the protective effect of SIN on IL-1beta-induced proteoglycan degradation and apoptosis in rabbit articular cartilage and chondrocytes. Treatment with 10 ng/ml IL-1beta increased the level of glycosaminoglycan (GAG) released into the culture media, and up-regulated the activity and mRNA expression of matrix metalloproteinase 13 (MMP-13) and down-regulated the activity and mRNA expression of tissue inhibitor of metalloproteinase 1 (TIMP-1) in cartilage explants, as confirmed by the methods of GAG quantitation, MMP-13/TIMP-1 enzyme-linked immunosorbent assay (ELISA) and real-time quantitative RT-PCR. Treatment with 10 ng/ml IL-1beta resulted in marked apoptosis in chondrocytes, as demonstrated by decreased cell viability, occurrence of DNA laddering and increased caspase-3 activity and annexin V binding of phosphatidylserine. However, simultaneous treatment with SIN (10, 50 or 250 microM) inhibited the GAG release and the activity and mRNA expression of MMP-13, and enhanced the activity and mRNA expression of TIMP-1 in a dose-dependent manner in cartilage explants. Furthermore, DNA fragment, caspase-3 activity and apoptosis rate were down-regulated, and cell viability was up-regulated dose-dependently in chondrocytes. Thus, SIN has the protective capacity to antagonize cartilage degradation and chondrocyte apoptosis, which suggest that SIN may act as an agent for pharmacological intervention in the progress of OA.
authors.affiliation: Institute of Sports Medicine, Peking University Third Hospital, Beijing, China.
authors.forename: Xiao-dong
authors.initials: XD
authors.lastname: Ju
authors.forename: Min
authors.initials: M
authors.lastname: Deng
authors.forename: Ying-fang
authors.initials: YF
authors.lastname: Ao
authors.forename: Chang-long
authors.initials: CL
authors.lastname: Yu
authors.forename: Jian-quan
authors.initials: JQ
authors.lastname: Wang
authors.forename: Jia-kuo
authors.initials: JK
authors.lastname: Yu
authors.forename: Guo-qing
authors.initials: GQ
authors.lastname: Cui
authors.forename: Yue-lin
authors.initials: YL
authors.lastname: Hu
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D002358:Cartilage, Articular / Q000378:metabolism* / Q000473:pathology; D053148:Caspase 3 / Q000378:metabolism; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D019902:Chondrocytes / Q000473:pathology*; D004305:Dose-Response Relationship, Drug; D006025:Glycosaminoglycans / Q000378:metabolism; D053509:Matrix Metalloproteinase 13 / Q000378:metabolism; D009019:Morphinans / Q000494:pharmacology* / Q000627:therapeutic use; D010003:Osteoarthritis / Q000188:drug therapy; D011817:Rabbits; D019715:Tissue Inhibitor of Metalloproteinase-1 / Q000378:metabolism
chemical_list: D006025:Glycosaminoglycans; D009019:Morphinans; D019715:Tissue Inhibitor of Metalloproteinase-1; C009271:sinomenine; D053148:Caspase 3; D053509:Matrix Metalloproteinase 13