Pectolinarigenin targeting FGFR3 alleviates osteoarthritis progression by regulating the NF-κB/NLRP3 inflammasome pyroptotic pathway.

ABSTRACT

OBJECTIVE: Osteoarthritis (OA) is a chronic degenerative disease characterized by cartilage degeneration, involving inflammation, pyroptosis, and degeneration of the extracellular matrix (ECM). Pectolinarigenin (PEC) is a natural flavonoid with antioxidant, anti-inflammatory and anti-tumor properties. This study aims to explore the potential of PEC in ameliorating OA progression and its underlying mechanisms. METHODS: Chondrocytes were exposed to 10 ng/mL IL-1ß to simulate OA-like changes. The effect of PEC on IL-1ß-treated chondrocytes was assessed using ELISA, western blot, and immunofluorescence. The mRNA sequencing (mRNA-seq) was employed to explore the possible targets of PEC in delaying OA progression. The OA mouse model was induced through anterior cruciate ligament transection (ACLT) and divided into sham, ACLT, ACLT+5 mg/kg PEC, and ACLT+10 mg/kg PEC groups. Micro-computed tomography and histological analysis were conducted to confirm the beneficial effects of PEC on OA in vivo. RESULTS: PEC mitigated chondrocyte pyroptosis, as evidenced by reduced levels of pyroptosis-related proteins. Additionally, PEC attenuated IL-1ß-mediated chondrocyte ECM degradation and inflammation. Mechanistically, mRNA-seq showed that FGFR3 was a downstream target of PEC. FGFR3 silencing reversed the beneficial effects of PEC on IL-1ß-exposed chondrocytes. PEC exerted anti-pyroptotic, anti-ECM degradative, and anti-inflammatory effects through upregulating FGFR3 to inhibit the NF-κB/NLRP3 pyroptosis-related pathway. Consistently, in vivo experiments demonstrated the chondroprotective effects of PEC in OA mice. CONCLUSION: PEC alleviate OA progression by FGFR3/NF-κB/NLRP3 pathway mediated chondrocyte pyroptosis, ECM degradation and inflammation, suggesting the potential of PEC as a therapeutic agent for OA.