Antarctic Krill Oil improves articular cartilage degeneration via activating chondrocyte autophagy and inhibiting apoptosis in osteoarthritis mice

In this study, the in vivo effects of Antarctic krill oil (AKO) on cartilage degeneration in destabilization of the medial meniscus (DMM) mouse were investigated. Results showed that AKO improved the cartilage structure, inhibited chondrocyte hypertrophic differentiation and inhibited abnormal apoptosis in articular cartilage. Autophagy is a self-protective metabolic process required for maintaining cartilage homeostasis. We observed that expression of mTOR were reduced, which was consist with high PPAR-gamma levels. The expression of key genes related to autophagy, including LC-3B, Beclin-1, ATG-5; and BNIP-3 were significantly enhanced after treatment with AKO. In addition, we observed that AKO suppressed the expression of key genes in p53-dependent mitochondrial apoptotic pathway, such as p53, Bax, Bid, cytochrome c, caspase-9, caspase-3 and enhanced the expression of anti-apoptotic genes, including Bcl-2 and Bcl-xl. These findings provided a new perspective for the effect of AKO on OA, which associated with the regulation of autophagy and apoptosis.