Aconiti Lateralis Radix Praeparata lipid-soluble alkaloids alleviates IL-1β-induced inflammation of human fibroblast-like synoviocytes in rheumatoid arthritis by inhibiting NF-κB and MAPKs signaling pathways and inducing apoptosis

Background: Fuzi lipid-soluble alkaloids (FLA) is the main bioactive components extracted from the traditional Chinese medicine Aconiti Lateralis Radix Praeparata ("Fuzi" in Chinese), which has promising analgesic and antiinflammatory effects. However, the effects and the underlying mechanisms of FLA on rheumatoid arthritis (RA) have not been studied. The present study aimed to explore the anti-arthritic effects of FLA and its underlying mechanisms. Methods: To standardize the FLA, UPLC-HR-MS was used for quantitative and qualitative analysis of the representative alkaloids. Cell viability was measured by MTT. The anti-inflammatory activity of FLA was examined by analyzing the expression levels of inflammatory mediators such as TNF-alpha, IL-6, MMP-1, MMP-3, PGE2, and COX2 using ELISA and RT-PCR analysis. The Annexin V-FITC/PI double staining method was used to detect the apoptosis of HFLS-RA and analyzed by flow cytometry. Western blot analysis was used to analyze the expression of NF-kappa B, MAPKs and mitochondrial apoptosis pathway related proteins. Results: FLA had a significant inhibitory effect on the proliferation of HFLS-RA induced by IL-1 beta, which was accompanied by decreased expression levels of TNF-alpha, IL-6, MMP-1, MMP-3, COX-2 and PGE2. Remarkably, FLA inhibited the activation of NF-kappa B and MAPKs signaling pathways in IL-1 beta-induced HFLS-RA, as well as inducing HFLS-RA apoptosis through the mitochondrial apoptosis pathway. Conclusions: FLA inhibited the expression and synthesis of inflammatory mediators by inhibiting the activation of NF-kappa B and MAPKs signaling pathways in HFLS-RA, and induced apoptosis of HFLS-RA via the mitochondrial apoptosis pathway.