Bushen Huoxue formula enhances anti-osteoarthritic efficacy of microfracture: Evidences for its mechanism of action.

Abstract

BACKGROUND: Arthroscopic microfracture (MF) is a common treatment for osteoarthritis (OA) but has limited long-term efficacy, especially in the elderly. Bushen Huoxue formula (BHF), a traditional Chinese medicine, has potential in OA treatment, yet its mechanisms underlying the enhancement of MF efficacy remain unclear. PURPOSE: To identify the constituents of BHF, evaluate the efficacy of BHF in enhancing the anti-OA effect of MF, and decipher the underlying mechanisms. METHODS: The chemoprofile of BHF was characterized using UPLC-Q/TOF-MS. OA model in rats was established using monosodium iodoacetate (MIA), and the therapeutic effect of BHF-MF combinatorial treatment was assessed through behavioral test, histopathology, and micro-CT. The migratory potential of BMSCs was evaluated using wound healing and transwell assays. The autophagy related mechanism was screened through network pharmacology, which was validated by Western blot and confocal imaging of autophagic flux in BMSCs. The requirement for autophagy was tested using chloroquine, siATG5, and siAMPK in vitro and by intra-tibial AAV-shATG5 or AAV-shAMPK delivery in vivo. RESULTS: 168 compounds were identified within BHF. In vivo studies demonstrated that BHF significantly improved the therapeutic efficacy of MF in OA rats. In vitro findings indicated that BHF enhanced the migratory capacity of BMSCs. Network pharmacology and experimental validation revealed that BHF promotes autophagy in BMSCs through the AMPK-mTOR pathway. CONCLUSIONS: This study presents, for the first time, the enhancing effect of BHF on MF in combating OA, offering a novel therapeutic strategy to enhance the clinical efficacy of MF against OA.