Knocking out RAGE disrupts natural repair of condylar cartilage during osteoarthritis (835.14)

Abstract

We have previously shown that knockout (KO) mice lacking the Receptor for Advanced Glycation End Products (RAGE) demonstrate attenuated osteoarthritis (OA) in articular cartilage of the knee. The objective of this research is to discover if knocking out RAGE has a similar protective effect in the condylar cartilage of the Temporomandibular joint (TMJ). Misalignment of the TMJ of Wild‐type (WT) and RAGE KO mice was performed, and severity of OA was assessed along with immunohistochemical staining of several known biomarkers of OA. An inverse relationship is known to exist between the expression of Htra1 and TGF‐B 1 in association with OA. We observed a reciprocal expression of these two proteins in WT but not RAGE KO mice. Condylar cartilage, unlike articular cartilage, has been shown to self‐repair when stress is applied. We hypothesize that the WT mice expressed higher levels of TGF‐B 1 as a result of natural repair processes. In contrast, RAGE KO mice lacked this pattern, suggesting that this receptor may play a role in the natural repair of condylar cartilage of the TMJ.