The mechanism by which pirfenidone inhibits apoptosis and inflammatory damage of bronchial epithelial cells in respiratory syncytial virus infection

GAO Shuai; LIU Baojuan; FU Xiaokang; SU Qin; WEI Quanping; SUN Zimei

doi:10.13431/j.cnki.immunol.j.20250068

Abstract：Objective To investigate the effect of Pirfenidone(PFN)on respiratory syncytial virus(RSV)infection-induced damage to bronchial epithelial cells by regulating the high mobility group protein B1(HMGB1)/receptor for advanced glycation end products(RAGE)signaling pathway.Methods Human bronchial epithelial cells(HBE)were divided into Control group(cultured for 24 h under normal conditions),RSV group(inoculated with 4.65×106/mL RSV at 33℃for 2 h);low PFN(L-PFN)group(treated with 0.05 mg/mL PFN for 24 h),moderate PFN(M-PFN)group(treated with 0.10 mg/mL PFN for 24 h),high PFN(H-PFN)group(treated with 0.20 mg/mL PFN for 24 h)and recombinant HMGB1(rHMGB1)group(treated with 1 μg/mL rHMGB1+0.20 mg/mL PFN for 24 h).EdU method was applied to detect the proliferation rate of cells in each group,Hochest33258 staining method was applied to detect apoptosis status of cells in each group,and the migration of cells in each group was evaluated by the scratch experiment.Enzyme linked immunosorbent assay(ELISA)was applied to measure the levels of interferon(IFN)-α,IFN-γ,tumor necrosis factor-α(TNF-α),interleukin(IL)-1α,IL-6 and IL-4 in each group of cells,and Western blot was applied to detect the protein expression of HMGB1,RAGE,B lymphoblastoma-2-associated X protein(Bax),cysteine aspartic protease-3(Caspase-3),and B lymphoblastoma-2(Bcl-2).Results Compared with the RSV group,the cell proliferation rate,scratch closure rate,IL-4 levels,and expression of Bcl-2 in L-,M-,and H-PFN groups increased,while the apoptosis rate,the levels of IFN-α,IFN-γ,TNF-α,IL-1α,IL-6,and the expression of HMGB1,RAGE,Bax,and Caspase-3 reduced(P<0.05);rHMGB1 weakened the effect of H-PFN on the above-mentioned indicators(P<0.05).Conclusion PFN may suppress the apoptosis and inflammatory damage of RSV-infected bronchial epithelial cells by inhibiting the HMGB1/RAGE pathway.Conclusion PFN may suppress the apoptosis and inflammatory damage of RSV-infected bronchial epithelial cells by inhibiting the HMGB1/RAGE pathway.