Feng Xu1, Man Luo1, Lulu He1, Yuan Cao1, Wen Li1, Songmin Ying1, Zhihua Chen1, Huahao Shen1,2. 1. Key Laboratory of Respiratory Disease of Zhejiang Province, Department of Respiratory and Critical Care Medicine, Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China. 2. State Key Laboratory of Respiratory Disease, Guangzhou, China.
Abstract
BACKGROUND/AIMS: Necroptosis, a form of programmed necrosis, is involved in the pathologic process of several kinds of pulmonary diseases. However, the role of necroptosis in particulate matter (PM)-induced pulmonary injury remains unclear. The objective of this study is to investigate the involvement of necroptosis in the pathogenesis of PM-induced toxic effects in pulmonary inflammation and mucus hyperproduction, both in vitro and in vivo. METHODS: PM was administered into human bronchial epithelial (HBE) cells or mouse airways, and the inflammatory response and mucus production were assessed. The mRNA expressions of IL6, IL8 and MUC5AC in HBE cells and Cxcl1, Cxcl2, and Gm-csf in the lung tissues were detected by quantitative real-time RT-PCR. The secreted protein levels of IL6 and IL8 in culture supernatants and Cxcl1, Cxcl2, and Gm-csf in bronchoalveolar lavage fluid (BALF) were detected by enzyme-linked immunosorbent assay (ELISA). We used Western blot to measure the protein expressions of necroptosis-related proteins (RIPK1, RIPK3, and Phospho-MLKL), NF-κB (P65 and PP65), AP-1 (P-c-Jun and P-c-Fos) and MUC5AC. Cell necrosis and mitochondrial ROS were detected using flow cytometry. In addition, pathological changes and scoring of lung tissue samples were monitored using hemoxylin and eosin (H&E), periodic acid-schiff (PAS) and immunohistochemistry staining. RESULTS: Our study showed that PM exposure induced RIP and MLKL-dependent necroptosis in HBE cells and in mouse lungs. Managing the necroptosis inhibitor Necrostatin-1 (Nec-1) and GSK'872, specific molecule inhibitors of necroptosis, markedly reduced PM-induced inflammatory cytokines, e.g., IL6 and IL8, and MUC5AC in HBE cells. Similarly, administering Nec-1 significantly reduced airway inflammation and mucus hyperproduction in PM-exposed mice. Mechanistically, we found PM-induced necroptosis was mediated by mitochondrial reactive oxygen species-dependent early growth response gene 1, which ultimately promoted inflammation and mucin expression through nuclear factor κB and activator protein-1 pathways, respectively. CONCLUSIONS: Our results demonstrate that necroptosis is involved in the pathogenesis of PM-induced pulmonary inflammation and mucus hyperproduction, and suggests that it may be a novel target for treatment of airway disorders or disease exacerbations with airborne particulate pollution.
BACKGROUND/AIMS: Necroptosis, a form of programmed necrosis, is involved in the pathologic process of several kinds of pulmonary diseases. However, the role of necroptosis in particulate matter (PM)-induced pulmonary injury remains unclear. The objective of this study is to investigate the involvement of necroptosis in the pathogenesis of PM-induced toxic effects in pulmonary inflammation and mucus hyperproduction, both in vitro and in vivo. METHODS: PM was administered into human bronchial epithelial (HBE) cells or mouse airways, and the inflammatory response and mucus production were assessed. The mRNA expressions of IL6, IL8 and MUC5AC in HBE cells and Cxcl1, Cxcl2, and Gm-csf in the lung tissues were detected by quantitative real-time RT-PCR. The secreted protein levels of IL6 and IL8 in culture supernatants and Cxcl1, Cxcl2, and Gm-csf in bronchoalveolar lavage fluid (BALF) were detected by enzyme-linked immunosorbent assay (ELISA). We used Western blot to measure the protein expressions of necroptosis-related proteins (RIPK1, RIPK3, and Phospho-MLKL), NF-κB (P65 and PP65), AP-1 (P-c-Jun and P-c-Fos) and MUC5AC. Cell necrosis and mitochondrial ROS were detected using flow cytometry. In addition, pathological changes and scoring of lung tissue samples were monitored using hemoxylin and eosin (H&E), periodic acid-schiff (PAS) and immunohistochemistry staining. RESULTS: Our study showed that PM exposure induced RIP and MLKL-dependent necroptosis in HBE cells and in mouse lungs. Managing the necroptosis inhibitor Necrostatin-1 (Nec-1) and GSK'872, specific molecule inhibitors of necroptosis, markedly reduced PM-induced inflammatory cytokines, e.g., IL6 and IL8, and MUC5AC in HBE cells. Similarly, administering Nec-1 significantly reduced airway inflammation and mucus hyperproduction in PM-exposed mice. Mechanistically, we found PM-induced necroptosis was mediated by mitochondrial reactive oxygen species-dependent early growth response gene 1, which ultimately promoted inflammation and mucin expression through nuclear factor κB and activator protein-1 pathways, respectively. CONCLUSIONS: Our results demonstrate that necroptosis is involved in the pathogenesis of PM-induced pulmonary inflammation and mucus hyperproduction, and suggests that it may be a novel target for treatment of airway disorders or disease exacerbations with airborne particulate pollution.
Authors: Leonid N Maslov; Sergey V Popov; Natalia V Naryzhnaya; Alexandr V Mukhomedzyanov; Boris K Kurbatov; Ivan A Derkachev; Alla A Boshchenko; Igor Khaliulin; N Rajendra Prasad; Nirmal Singh; Alexei Degterev; Evgenia A Tomilova; Ekaterina V Sapozhenkova Journal: Apoptosis Date: 2022-08-20 Impact factor: 5.561
Authors: Wenjun Li; Yuriko Terada; Yulia Y Tyurina; Vladimir A Tyurin; Amit I Bery; Jason M Gauthier; Ryuji Higashikubo; Alice Y Tong; Dequan Zhou; Felix Nunez-Santana; Emilia Lecuona; Adil Hassan; Kohei Hashimoto; Davide Scozzi; Varun Puri; Ruben G Nava; Alexander S Krupnick; Kory J Lavine; Andrew E Gelman; Mark J Miller; Valerian E Kagan; Ankit Bharat; Daniel Kreisel Journal: Proc Natl Acad Sci U S A Date: 2022-03-01 Impact factor: 12.779