Tao Zhao1,2, Hongwei Zhao1, Gang Li1, Shengfa Zheng1, Mengjie Liu2, Changping Gu2, Yuelan Wang3. 1. Department of Anesthesiology, Rizhao People's Hospital, Rizhao, China. 2. Department of Anesthesiology, Qianfoshan Hospital, Shandong University, Jinan, China. 3. Department of Anesthesiology, Qianfoshan Hospital, Shandong University, Jinan, China. wyldgf@163.com.
Abstract
BACKGROUND AND OBJECTIVE: Ventilator-induced lung injury (VILI) is commonly associated with respiratory barrier dysfunction; however, the mechanisms have not been fully elucidated. This study aimed to determine the order and components of the signalling pathway that mediates the degradation of adherin junction of p120-catenin in VILI. METHODS: For the in vivo study, C57BL/6 mice were pre-treated with inhibitors for 60 min prior to 4 h of mechanical ventilation. For the in vitro study, mouse lung epithelial 12 (MLE-12) cells were pre-treated with inhibitors for 60 min or small interfering RNA (siRNA) for 48 h prior to cyclic stretch at 20% for 4 h. The protein levels of protein kinase Cα (PKCα), activated c-Src and p120-catenin were determined via western blot analysis. Lung injury was determined via HE staining, immunofluorescence, wet/dry ratio and lung injury scores. RESULTS: High tidal volume mechanical ventilation and 20% cyclic stretch resulted in the degradation of p120-catenin. Inhibitors of PKCα blocked c-Src kinase activation and p120-catenin degradation in VILI. Inhibitors of c-Src kinase or PP2 or siRNA blocked p120-catenin degradation but not PKCα activation. CONCLUSION: The current findings demonstrates that PKCα and c-Src kinase participate in VILI. PKCα activation phosphorylates c-Src kinase and further decreases p120-catenin in VILI.
BACKGROUND AND OBJECTIVE: Ventilator-induced lung injury (VILI) is commonly associated with respiratory barrier dysfunction; however, the mechanisms have not been fully elucidated. This study aimed to determine the order and components of the signalling pathway that mediates the degradation of adherin junction of p120-catenin in VILI. METHODS: For the in vivo study, C57BL/6 mice were pre-treated with inhibitors for 60 min prior to 4 h of mechanical ventilation. For the in vitro study, mouse lung epithelial 12 (MLE-12) cells were pre-treated with inhibitors for 60 min or small interfering RNA (siRNA) for 48 h prior to cyclic stretch at 20% for 4 h. The protein levels of protein kinase Cα (PKCα), activated c-Src and p120-catenin were determined via western blot analysis. Lung injury was determined via HE staining, immunofluorescence, wet/dry ratio and lung injury scores. RESULTS: High tidal volume mechanical ventilation and 20% cyclic stretch resulted in the degradation of p120-catenin. Inhibitors of PKCα blocked c-Src kinase activation and p120-catenin degradation in VILI. Inhibitors of c-Src kinase or PP2 or siRNA blocked p120-catenin degradation but not PKCα activation. CONCLUSION: The current findings demonstrates that PKCα and c-Src kinase participate in VILI. PKCα activation phosphorylates c-Src kinase and further decreases p120-catenin in VILI.
Authors: Ting Wang; Christine Gross; Ankit A Desai; Evgeny Zemskov; Xiaomin Wu; Alexander N Garcia; Jeffrey R Jacobson; Jason X-J Yuan; Joe G N Garcia; Stephen M Black Journal: Am J Physiol Lung Cell Mol Physiol Date: 2016-12-15 Impact factor: 5.464