Pneumonia is one of the common respiratory diseases in pediatrics. Ubiquitin-specific protease 14 (USP14) contributes the progress of inflammation-associated diseases. Poly (ADP-ribose) polymerase-1 (PARP-1) involves in the signal transduction of inflammatory pulmonary disease. This study aims to identify the precise function and elaborate the regulatory mechanism of USP14/PARP-1 in the injury of lung epithelial cells. Human lung epithelial BEAS-2B cells received lipopolysaccharide (LPS) (0, 1, 5, and 10 mg/L) treatment for 16 h, establishing in vitro pneumonia model. USP14 protein and mRNA levels in LPS-injured lung epithelial cells were separately assessed using western blot and RT-qPCR analysis. Lung epithelial cells were transfected with siRNA-USP14 or OV-USP14 to perform gain- or loss-of-function experiments. CCK-8 assay was applied to assess cell viability. TUNEL staining and western blot analysis were adopted to determine cell apoptosis. In addition, release of inflammatory cytokines and nitric oxide (NO) was detected using the commercial kits. Meanwhile, PARP-1 protein levels in LPS-injured lung epithelial cells were detected by performing western blot assay. Moreover, Co-IP assay was utilized for detection of the interaction between USP14 and PARP-1. The regulatory effects of PARP-1 on USP14 function in LPS-injured lung epithelial cells were also investigated. LPS dose-dependently reduced viability of lung epithelial cells and elevated USP14 protein. USP14 combined with PARP-1 and increased PARP-1 expression. USP14 elevation exacerbated inflammatory injury and boosted the apoptosis of LPS-injured lung epithelial cells, which was reversed upon downregulation of PARP-1. To sum up, USP14 promotion exacerbated inflammatory injury and boosted the apoptosis of LPS-injured lung epithelial cells by upregulating PARP-1 expression. These findings may represent a therapeutic target for clinical intervention in pneumonia.

肺炎是儿科常见的呼吸道疾病之一。泛素特异性蛋白酶 14 (USP14) 有助于炎症相关疾病的进展。聚 (ADP-核糖) 聚合酶 1 (PARP-1) 参与炎症性肺病的信号转导。本研究旨在明确USP14/PARP-1在肺上皮细胞损伤中的确切功能并阐明其调控机制。人肺上皮 BEAS-2B 细胞接受脂多糖 (LPS) (0、1、5 和 10 mg/L) 处理 16 小时，在体外建立肺炎模型。使用蛋白质印迹和 RT-qPCR 分析分别评估 LPS 损伤的肺上皮细胞中的 USP14 蛋白和 mRNA 水平。用 siRNA-USP14 或 OV-USP14 转染肺上皮细胞以进行功能增益或功能丧失实验。应用 CCK-8 测定来评估细胞活力。采用TUNEL染色和蛋白质印迹分析来确定细胞凋亡。此外，使用商业试剂盒检测到炎症细胞因子和一氧化氮 (NO) 的释放。同时，通过蛋白质印迹法检测LPS损伤的肺上皮细胞中PARP-1蛋白水平。此外，Co-IP 测定用于检测 USP14 和 PARP-1 之间的相互作用。还研究了 PARP-1 对 LPS 损伤肺上皮细胞中 USP14 功能的调节作用。LPS 剂量依赖性地降低肺上皮细胞的活力和升高的 USP14 蛋白。USP14 与 PARP-1 结合并增加了 PARP-1 的表达。USP14 升高加剧了炎症损伤并促进了 LPS 损伤的肺上皮细胞的凋亡，这在 PARP-1 的下调后被逆转。综上所述，USP14 促进通过上调 PARP-1 表达加剧了炎症损伤并促进了 LPS 损伤肺上皮细胞的凋亡。这些发现可能代表了肺炎临床干预的治疗靶点。USP14 促进通过上调 PARP-1 表达加剧了炎症损伤并促进了 LPS 损伤的肺上皮细胞的凋亡。这些发现可能代表了肺炎临床干预的治疗靶点。USP14 促进通过上调 PARP-1 表达加剧了炎症损伤并促进了 LPS 损伤的肺上皮细胞的凋亡。这些发现可能代表了肺炎临床干预的治疗靶点。