Protective effects of gemigliptin against type II collagen degradation in human chondrocytes.

Degradation of components of the extracellular matrix such as type II collagen in articular cartilage induced by matrix metalloproteinases (MMPs) has been considered as a major pathological characteristic of osteoarthritis (OA). Gemigliptin is a potent and a highly selective dipeptidyl peptidase-IV (DPP-IV) inhibitor, which has been clinically used as an oral agent for the treatment of type 2 diabetes. However, the effects of gemigliptin on articular cartilage destruction and the pathogenesis of OA remain unknown. In the current study, we addressed for the first time the inhibitory property of gemigliptin against interleukin-1β (IL-1β)-induced degradation of type II collagen in human chondrocytes. Our results demonstrate that gemigliptin treatment inhibited the expression of matrix metalloproteinase 1 (MMP-1), matrix metalloproteinase 3 (MMP-3), and matrix metalloproteinase 13 (MMP-13) at both the gene and protein levels. Mechanistically, our results indicate that gemigliptin inhibited activation of the nuclear factor-κB (NF-κB) signaling pathway by suppressing phosphorylation of IκB kinase (IKK)/nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor α (IκBα) and p38. Our results implicate that gemigliptin treatment might be a potential therapeutic strategy for chondroprotective therapy.