Yiqi Yangxue Qufeng Mixture alleviates knee osteoarthritis by modulating mitochondrialoxidative stress and suppressing ferroptosis via the PRKCA-MAPK/ERK axis

Background Knee osteoarthritis (KOA) is one of the most common degenerative joint diseases globally, which significantly impairs patients' quality of life. Currently, effective approaches capable of reversing or significantly delaying disease progression are still lacking, and the long-term prognosis for patients remains suboptimal. This experiment aimed to validate the therapeutic efficacy of Yiqi Yangxue Qufeng Mixture (YQYXQF) in treating KOA and to elucidate the specific mechanisms through which YQYXQF alleviates KOA by restoring mitochondrial function. Methods The therapeutic efficacy of YQYXQF in treating KOA was systematically evaluated using a mouse model of knee osteoarthritis established via destabilization of medial meniscus (DMM) surgery. In vitro, the protective effects of YQYXQF on chondrocytes were evaluated in an IL‑1β‑induced inflammatory microenvironment mimicking KOA. From an integrated analysis of single-cell omics and transcriptomics, Protein kinase C alpha (PRKCA) emerged as a candidate target for KOA therapy. Subsequent investigation of the LC-MS/MS-identified active components of YQYXQF was undertaken through network pharmacology and molecular dynamics simulations. Combined with in vitro and in vivo animal experiments validated the interaction between YQYXQF and PRKCA within the therapeutic mechanism of osteoarthritis. Results In vivo, YQYXQF significantly ameliorated knee joint injury induced by DMM surgery in mice. In vitro, YQYXQF treatment markedly improved mitochondrial morphology in chondrocytes under IL-1β-simulated osteoarthritic conditions, alleviated mitochondrial oxidative stress, and reduced chondrocyte ferroptosis. Through the integrated application of Single-cell RNA-seq, Transcriptomics, and network pharmacology, the involvement of PRKCA in KOA progression was identified. Mechanistically, YQYXQF inhibited PRKCA expression, attenuated the phosphorylation-mediated activation of the MAPK/ERK signalling pathway, restored mitochondrial function, and mitigated mitochondrial oxidative stress and ferroptosis, ultimately protecting chondrocytes and ameliorating osteoarthritis. Conclusion This study provides novel evidence that the traditional Chinese medicine (TCM) decoction YQYXQF exerts its biological effects by inhibiting PRKCA expression, thereby modulating the MAPK/ERK signalling pathway and restoring the function of the mitocondria. This ultimately leads to the alleviation of mitochondrial oxidative stress and ferroptosis in chondrocytes. These findings not only underscore the potential of the TCM compound YQYXQF as a therapeutic agent for KOA, but also provide a novel approach for targeting PRKCA/MAPK/ERK in the treatment of KOA.