Department of Respiratory and Critical Care Medicine, Zhongshan Hospital Xiamen University, Xiamen, China.
Department of Geriatrics, Zhongshan Hospital Xiamen University, Xiamen, China.
Clin Exp Pharmacol Physiol. 2023 Dec;50(12):992-1004. doi: 10.1111/1440-1681.13826. Epub 2023 Oct 2.
Pneumonia is an inflammatory disease in lower respiratory tracts and its development involves the regulation of RNAs. Circular RNAs are a class of RNA subgroups that can mediate the progression of pneumonia. However, the molecular mechanism of circ_0026579 in regulating pneumonia occurrence remains unclear. The study is designed to reveal the role of circ_0026579 in lipopolysaccharide (LPS)-induced human lung fibroblast cell injury and the underlying mechanism. The expression levels of circ_0026579, miR-370-3p and C-X-C motif chemokine receptor 1 (CXCR1) were detected by quantitative real-time polymerase chain reaction or by western blotting. The production of tumour necrosis factor-α, interleukin (IL)-1β and IL-6 was assessed by enzyme-linked immunosorbent assays. Malondialdehyde and superoxide dismutase levels were analysed using commercial kits. Cell viability, proliferation and apoptosis were analysed by cell counting kit-8 assay, 5-Ethynyl-2'-deoxyuridine assay and flow cytometry analysis, respectively. The binding relationship between miR-370-3p and circ_0026579 or CXCR1 was identified by dual-luciferase reporter assay, RNA immunoprecipitation assay and RNA pull-down assay. Circ_0026579 and CXCR1 expression were significantly upregulated, whereas miR-370-3p was downregulated in the serum of pneumonia patients. LPS treatment induced inflammatory response, oxidative stress and cell apoptosis and inhibited cell proliferation in MRC-5 cells; however, these effects were reversed after circ_0026579 depletion. In terms of the mechanism, circ_0026579 acted as a miR-370-3p sponge, and miR-370-3p combined with CXCR1. Additionally, circ_0026579 depletion ameliorated LPS-induced MRC-5 cell disorder by increasing miR-370-3p expression. CXCR1 overexpression also relieved the miR-370-3p-mediated effects in LPS-treated MRC-5 cells. Further, circ_0026579 induced CXCR1 expression by interacting with miR-370-3p. Circ_0026579 absence ameliorated MRC-5 cell dysfunction induced by LPS through the regulation of the miR-370-3p/CXCR1 axis.
肺炎是一种下呼吸道炎症性疾病，其发生发展涉及 RNA 的调控。环状 RNA 是 RNA 亚群的一种，可以介导肺炎的进展。然而，circ_0026579 调节肺炎发生的分子机制尚不清楚。本研究旨在揭示 circ_0026579 在脂多糖（LPS）诱导的人肺成纤维细胞损伤中的作用及其潜在机制。通过定量实时聚合酶链反应或 Western 印迹检测 circ_0026579、miR-370-3p 和 C-X-C 基序趋化因子受体 1（CXCR1）的表达水平。酶联免疫吸附试验检测肿瘤坏死因子-α、白细胞介素（IL）-1β 和 IL-6 的产生。使用商业试剂盒分析丙二醛和超氧化物歧化酶水平。通过细胞计数试剂盒-8 测定、5-乙炔基-2'-脱氧尿苷测定和流式细胞术分析分别评估细胞活力、增殖和凋亡。通过双荧光素酶报告基因测定、RNA 免疫沉淀测定和 RNA 下拉测定鉴定 miR-370-3p 与 circ_0026579 或 CXCR1 的结合关系。肺炎患者血清中 circ_0026579 和 CXCR1 表达明显上调，而 miR-370-3p 表达下调。LPS 处理诱导 MRC-5 细胞炎症反应、氧化应激和细胞凋亡，抑制细胞增殖；然而，circ_0026579 耗竭后这些作用得到逆转。就机制而言，circ_0026579 充当 miR-370-3p 的海绵，miR-370-3p 与 CXCR1 结合。此外，circ_0026579 通过增加 miR-370-3p 的表达来改善 LPS 诱导的 MRC-5 细胞紊乱。CXCR1 过表达也减轻了 LPS 处理的 MRC-5 细胞中 miR-370-3p 介导的作用。此外，circ_0026579 通过与 miR-370-3p 相互作用诱导 CXCR1 表达。circ_0026579 通过调节 miR-370-3p/CXCR1 轴来改善 LPS 诱导的 MRC-5 细胞功能障碍。
