Programmed cell death 4 governs NLRP3-mediated pyroptosis in septic lung disorders.

ABSTRACT

INTRODUCTION: Sepsis is a pathogenic syndrome of prolonged excessive inflammation and immunosuppression produced by invading pathogens. Programmed cell death 4 (PDCD4) may be implicated in a range of inflammatory lesions, and this study aimed to confirm the involvement of PDCD4 in septic lung injury. MATERIALS AND METHODS: Mice and bronchial epithelial 16HBE cells were separately subjected to CLP and LPS to generate in vivo and in vitro models. Following the level of PDCD4 was determined, the impacts of PDCD4 knockdown on mouse lung injury degree, inflammation, apoptosis, and pyroptosis levels were evaluated. Afterward, cells were treated with the NLRP3 agonist, and the influences of NLRP3 activation on the regulations of PDCD4 knockdown were determined. RESULTS: PDCD4 was elevated following mice developed septic lung injury, PDCD4 knockdown ameliorated septic lung injury and reduced lung inflammation and apoptosis. Moreover, PDCD4 knockdown suppressed NLRP3-mediated pyroptosis, indicating that PDCD4 also mediated pyroptosis. According to cellular models, NLRP3 activation broke the effects of PDCD4 knockdown on cells. CONCLUSIONS: The current study reveals that PDCD4 governs NLRP3-mediated pyroptosis in septic lung injury. PDCD4 is not only related to apoptosis and expands the knowledge of PDCD4 regulation of different cell death modes.