Chen Song, Zhu Haijun, Sun Jie, Zhu Lili, Qin Long, Wan Jian
Department of Emergency and Critical Care Medicine, The People's Hospital of Pudong New Area, Shanghai University of Health and Science, Shanghai 201200, P.R. China.
Exp Ther Med. 2021 Oct;22(4):1049. doi: 10.3892/etm.2021.10483. Epub 2021 Jul 23.
Sepsis is a condition that is associated with high rates of mortality. It is characterized by serious systemic inflammatory responses induced by pathogenic invasion. Although microRNA-150 (miR-150) has been previously reported to be involved in the modulation of sepsis, the underlying molecular mechanism in sepsis remains poorly understood. In the present study, the human monocytic cell line THP-1 was treated with LPS to mimic sepsis , following which miR-150 and STAT1 expression were measured using reverse transcription-quantitative PCR or western blotting. Secretion of inflammatory cytokines interleukin (IL)-1β, IL-6 and tumor necrosis factor-α (TNF-α) into the medium were measured by ELISA. The potential relationship between STAT1 and miR-150 was determined using dual-luciferase reporter and RNA immunoprecipitation assays. miR-150 expression was found to be was downregulated by LPS treatment in THP-1 cells in both dose- and time-dependent manners. LPS treatment also induced IL-1β, IL-6 and TNF-α secretion in a manner that could be inhibited by miR-150 overexpression and enhanced by transfection with the miR-150 inhibitor. miR-150 was revealed to directly target STAT1 by negatively regulating its expression. In addition, STAT1 expression was demonstrated to be upregulated by LPS treatment. STAT1 overexpression reversed the inhibitory effects of miR-150 overexpression on IL-1β, IL-6 and TNF-α secretion whilst STAT1 knockdown attenuated IL-1β, IL-6 and TNF-α secretion induced by miR-150 inhibitor transfection. In conclusion, the present study suggested that miR-150 regulates the inflammatory response in macrophages following LPS challenge by regulating the expression of STAT1.
脓毒症是一种与高死亡率相关的病症。其特征是由病原体入侵引发的严重全身炎症反应。尽管先前已有报道称微小RNA - 150（miR - 150）参与脓毒症的调节，但脓毒症潜在的分子机制仍知之甚少。在本研究中，使用脂多糖（LPS）处理人单核细胞系THP - 1以模拟脓毒症，随后采用逆转录定量聚合酶链反应或蛋白质免疫印迹法检测miR - 150和信号转导子和转录激活子1（STAT1）的表达。通过酶联免疫吸附测定法检测炎性细胞因子白细胞介素（IL）-1β、IL - 6和肿瘤坏死因子-α（TNF - α）向培养基中的分泌情况。使用双荧光素酶报告基因和RNA免疫沉淀试验确定STAT1与miR - 150之间的潜在关系。结果发现，LPS处理以剂量和时间依赖性方式下调THP - 1细胞中miR - 150的表达。LPS处理还以一种可被miR - 150过表达抑制且被miR - 150抑制剂转染增强的方式诱导IL - 1β、IL - 6和TNF - α的分泌。研究表明，miR - 150通过负向调节STAT1的表达直接靶向STAT1。此外，LPS处理可使STAT1表达上调。STAT1过表达逆转了miR - 150过表达对IL - 1β、IL - 6和TNF - α分泌的抑制作用，而STAT1基因敲低减弱了miR - 150抑制剂转染诱导的IL - 1β、IL - 6和TNF - α分泌。总之，本研究表明，miR - 150通过调节STAT1的表达来调控LPS刺激后巨噬细胞中的炎症反应。
