Evodiamine alleviates IL-1β-induced chondrocyte damage by regulating mitochondrial dysfunction via the SIRT1/PGC-1α pathway.

Osteoarthritis (OA) is a degenerative joint disease characterized by pathological changes such as articular cartilage degeneration and bone hyperplasia. Mitochondrial dysfunction in chondrocytes has been identified as a critical factor contributing to the progression of OA. Although Evodiamine (Evo) has been demonstrated effeicacy in inhibiting inflammatory responses and matrix degradation in OA chondrocytes, its effects and underlying mechanisms regarding mitochondrial dysfunction in these cells remain to be elucidated. IL-1β was utilized to stimulate chondrocytes in order to establish an in vitro OA model. Subsequently, the proliferation, lactate dehydrogenase (LDH) release, and apoptosis of chondrocytes were systematically evaluated. Mitochondrial function in chondrocytes was evaluated by quantifying of ATP content, ROS level, mitochondrial DNA (mtDNA) copy number, activities of mitochondrial respiratory chain Complexes I and III, as well as mitochondrial membrane potential change. Furthermore, the protein expression levels of the SIRT1/PGC-1α signaling pathway were examined, and an intervention involving the SIRT1 inhibitor EX527 was conducted to elucidate the potential mechanisms underlying the effects of Evo on chondrocytes. Evo treatment significantly elevated the proliferation activity of IL-1β-stimulated chondrocytes, inhibited LDH release and apoptosis, increased mtDNA copy number and ATP content, enhanced the enzymatic activities of Complexes I and III, and suppressed ROS production as well as mitochondrial membrane potential loss. Furthermore, Evo treatment activated the SIRT1/PGC-1α signaling pathway. However, the addition of the SIRT1 inhibitor EX-527 partially attenuated the protective effects of Evo against IL-1β-induced chondrocyte injury by exacerbating mitochondrial dysfunction. Evo promotes mitochondrial biosynthesis, reduces ROS production and improves mitochondrial function by activating SIRT1/PGC-1α pathway, thereby inhibiting IL-1β-induced chondrocyte injury.