Delayed progression of condylar cartilage degeneration, by reduction of the discoidin domain receptor 2, in the temporomandibular joints of osteoarthritic mouse models.

Abstract

OBJECTIVE: To determine whether reduction of the discoidin domain receptor 2 (Ddr2) delays the progression of condylar cartilage degeneration in the temporomandibular joint (TMJ) of mouse models with osteoarthritis (OA). METHODS: Double-heterozygous (Col11a1- and Ddr2-haploinsufficiency, Col11a1(+/−);Ddr2(+/−)) mice were generated. TMJs of Ddr2(+/−) mice were subjected to partial discectomy. Condylar cartilage from the TMJ of Col11a1(+/−);Ddr2(+/−) mice, surgically treated (discectomy) Ddr2(+/−) mice, and their corresponding controls was characterized by means of histology and evaluated using a scoring system specific to mouse joints. RESULTS: The progression of condylar cartilage degeneration was significantly delayed in the TMJ of Col11a1(+/−);Ddr2(+/−) mice compared with those of the Col11a1(+/−) mice. The progression of condylar cartilage degeneration in the TMJ of Ddr2(+/−) mice following discectomy was also significantly delayed when compared with their wild-type littermates. CONCLUSION: Reduced expression of Ddr2 delays the progression of condylar cartilage degeneration, induced either by type XI collagen haploinsufficiency or by a partial discectomy, in TMJ.