title: Osteoprotegerin deficiency leads to deformation of the articular cartilage in femoral head.
abstract: Osteoarthritis (OA) was a degenerative joint disease characterized by articular cartilage degradation and extensive remodeling of the subchondral bone. Multiple lines of evidence indicated that Osteoprotegerin (OPG), a member of TNF receptor superfamily that was expressed in the chondrocytes of articular cartilage and adjacent locations in the physiological setting, was involved in maintaining integrity of articular cartilage. OPG could prevent subchondral bone from resorption, and also protect cartilage from degradation. In this study, we used Osteoprotegerin-knockout mice (Opg-KO mice) to find out the role of OPG in articular cartilage. We examined articular cartilage in the femoral head of Opg-KO mice began in early adulthood using modern molecular and imaging methods. We found cartilage changes starting from adulthood and progressively with age, reminiscent of pathological changes in OA. Deficiency of OPG caused thinned articular cartilage and extensive remodeling of the subchondral bone in femoral head in comparison with wild-type mice (WT mice). Also, the articular cartilage of femoral head expressed significantly less of Aggrecan, Col-II and Col-X, but more Col-I and Matrix Metalloproteinases-13 (Mmp-13) than WT mice both at gene and protein level. Moreover, increased chondrocyte apoptosis and decreased chondrocyte proliferation were observed in femoral head of Opg-KO mice compared to WT mice. These data suggested that OPG played an important role in maintaining the homeostasis of articular cartilage of femoral head.
authors.affiliation: Department of Endodontics, School & Hospital of Stomatology, Tongji University, Shanghai Engineering Research Center of Tooth Restoration and Regeneration, Shanghai, 200072, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Department of Endodontics, School & Hospital of Stomatology, Tongji University, Shanghai Engineering Research Center of Tooth Restoration and Regeneration, Shanghai, 200072, China.
authors.forename: Jianping
authors.initials: J
authors.lastname: Ge
authors.affiliation: Department of Endodontics, School & Hospital of Stomatology, Tongji University, Shanghai Engineering Research Center of Tooth Restoration and Regeneration, Shanghai, 200072, China.
authors.forename: Danying
authors.initials: D
authors.lastname: Chen
authors.affiliation: Department of Endodontics, School & Hospital of Stomatology, Tongji University, Shanghai Engineering Research Center of Tooth Restoration and Regeneration, Shanghai, 200072, China.
authors.forename: Yuteng
authors.initials: Y
authors.lastname: Weng
authors.affiliation: Department of Endodontics, School & Hospital of Stomatology, Tongji University, Shanghai Engineering Research Center of Tooth Restoration and Regeneration, Shanghai, 200072, China.
authors.forename: Haiming
authors.initials: H
authors.lastname: Du
authors.affiliation: Department of Endodontics, School & Hospital of Stomatology, Tongji University, Shanghai Engineering Research Center of Tooth Restoration and Regeneration, Shanghai, 200072, China.
authors.forename: Yao
authors.initials: Y
authors.lastname: Sun
authors.affiliation: Department of Endodontics, School & Hospital of Stomatology, Tongji University, Shanghai Engineering Research Center of Tooth Restoration and Regeneration, Shanghai, 200072, China. qizhang@tongji.edu.cn.
authors.forename: Qi
authors.initials: Q
authors.lastname: Zhang
mesh_terms: D000818:Animals; D002358:Cartilage, Articular / Q000378:metabolism* / Q000473:pathology*; D002452:Cell Count; D002470:Cell Survival / Q000235:genetics; D019902:Chondrocytes / Q000378:metabolism; D004195:Disease Models, Animal; D005109:Extracellular Matrix / Q000378:metabolism; D005270:Femur Head / Q000000981:diagnostic imaging / Q000378:metabolism* / Q000473:pathology*; D051379:Mice; D018345:Mice, Knockout; D010003:Osteoarthritis / Q000000981:diagnostic imaging / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D010010:Osteoclasts / Q000378:metabolism; D010012:Osteogenesis / Q000235:genetics*; D053244:Osteoprotegerin / Q000172:deficiency*; D055114:X-Ray Microtomography
chemical_list: D053244:Osteoprotegerin
keywords: Articular cartilage; Degenerative joint disease; Femoral head; OPG; Osteoarthritis