Research on the effect of N-acetylcysteine on ROS/NLRP3-mediated pyroptosis in BEAS-2B Cells and bronchial epithelial tissues from patients with AECOPD.

OBJECTIVE: This study investigated the impact of cigarette smoke extract (CSE) on BEAS-2B bronchial epithelial cells, focusing on whether it induces pyroptosis via the ROS/NLRP3/GSDMD pathway and how NAC protects these cells from pyroptosis. METHODS: BEAS-2B cells were treated with varying CSE concentrations, and cellular damage was evaluated via PI staining and release of ROS and LDH. Cellular morphology alterations were examined by immunohistochemistry, and IL-18 and IL-1β release were measured by ELISA. Western blot analysis was used to assess expression of proteins linked to pyroptosis, including ASC, NLRP3, cleaved-caspase-1, GSDMD-N, and IL-1β. Caspase-1 and GSDMD inhibitors were utilized to elucidate the underlying mechanisms. RESULTS: Following CSE treatment, bronchial epithelial cells demonstrated inflammatory infiltration and membrane rupture and increased ROS, NLRP3, cleaved-caspase-1, GSDMD-N, IL-18, and IL-1β expression. Treatment with caspase-1 and GSDMD inhibitors decreased expression of these markers, as expected. Interestingly, NAC treatment reduced the expression of these proteins compared to the CSE group, suggesting a protective role against pyroptosis through inhibition of the ROS/NLRP3/GSDMD pathway. CONCLUSION: The study shows that CSE triggers pyroptosis in COPD via the ROS/NLRP3/GSDMD pathway, with NAC offering antioxidative protection. These findings enhance understanding of AECOPD pathophysiology and support NAC's therapeutic role in treatment.