Enhancement of autophagy flux by isopsoralen ameliorates interleukin-1β-stimulated apoptosis in rat chondrocytes

Abstract

Chondrocyte apoptosis contributes to the pathogenesis of cartilage degeneration in osteoarthritis (OA). We found that isopsoralen pretreatment significantly reversed the increase in DNA fragmentation and apoptosis rate, and significantly decreased the caspase-3 activity and PARP cleavage in IL-1β-treated chondrocytes. Isopsoralen pretreatment markedly inhibited disruption of matrix proteins. Moreover, the expressions of LC3-II and LAMP-1 were markedly increased but the expression of p62/SQSTM1 was remarkably decreased by isopsoralen pretreatment. Importantly, the protective effects of isopsoralen against IL-1β were blocked by pretreatment with autophagy inhibitor 3-MA and bafilomycin A1. These results suggest that isopsoralen ameliorates chondrocyte apoptosis by promoting autophagy flux.

Keywords:

• Osteoarthritis
• autophagy
• isopsoralen
• inflammation
• apoptosis

Funding

This work was financially supported by the Applied Basic Research Programs of Social development fund of Jiangxi Province (No. 20151BBG70120).

Disclosure statement

No potential conflict of interest was reported by the authors.