Protective Effect And Mechanism Of NAC/RvD1 On H₂O₂-induced Diseased Human Bronchial Epithelial Cell Of COPD Of Inflammatory Response And Mucus Hypersecretion

Objective:Chronic obstructive pulmonary disease（COPD）,a chronic inflammation of the airways disease,is most prominently characterized by persistent airflow limitation that is usually progressive.Oxidative stress（OS）is one of the important mechanisms in the development of COPD.Aiming at the target of oxidative stress,it is significant to alleviate the symptoms,slow down the development of the disease and improve the prognosis of COPD patients.The aim of this study was to investigate the molecular mechanisms of inflammatory response and mucus hypersecretion of N-Acetyl-L-cysteine（NAC）or Resolvin-D1（RvD1）inhibit hydrogen peroxide(H₂O₂)-induced Diseased human bronchial epithelial cell of COPD（DHBE）of inflammation and mucus hypersecretion.Provide new ideas for the clinical prevention and treatment of COPD patients.Methods:Isolation,identification and culture of DHBE cells,DHBE cells were treated with H₂O₂ at different concentration gradients（0-500μmol/L）,cell viability was detected by MTT,IKKβand NF-κB protein expression and phosphorylation levels were detected by Western blot at different concentration gradients,and the optimal stimulation concentration was sought.Finally,the oxidative stress model was established with the300μmol/L H₂O₂ by stimulating DHBE and incubated with NAC and RvD1 in vitro.Measuring reactive oxygen species（ROS）by flow cytometry and immunofluorescence;IKKβand NF-κB protein expressions and the phosphorylation level were detected respectively by Western blot;the m RNA expression and secretion levels of interleukin-8（IL-8）and tumor necrosis factor（TNF-α）were detected by ELISA and q RT-PCR;Mucin 5AC（MUC5AC）protein expression was detected by q RT-PCR and immunofluorescence.Results:Compared with the control group,H₂O₂stimulated DHBE cells,the oxidative stress level of H₂O₂ group was significantly increased,specifically,the expression level of Reactive oxygen species（ROS）was significantly increased（P<0.01）,the expressions of IKK?and NF-κB phosphorylation increased in a concentration-dependent manner（P<0.05）,NF-κB signaling pathway activation,the Intracellular m RNA levels of IL-8,TNF-αand protein levels of IL-8,TNF-αin cell culture medium increased（P<0.01）,Immunofluorescence showed that MUC5AC expression was increased（P<0.001）.DHBE cells was pretreated by NAC or RvD1,and it was found that NAC or RvD1exerted anti oxidative stress effects,blocked NF-κB signaling pathway,and significantly inhibited IL-8,TNF-αand MUC5AC expression induced by H₂O₂（P<0.01）.Conclusions:Oxidative stress is involved in the occurrence of chronic obstructive pulmonary disease.NAC and RVD1 may play a protective role in oxidative stress on DHBE cell inflammation and mucus hypersecretion through the NF-κB signaling pathway,and improve inflammatory mucus hypersecretion.NAC and RVD1 may be candidates for clinical treatment of chronic obstructive pulmonary disease.