Zhang Yu, Wu Xiaxin, Wu Jinfeng, Li Shuang, Han Sen, Lin Zhijie, Ding Shizhen, Jia Xiaoqin, Gong Weijuan
School of Nursing, Yangzhou University Yangzhou, China.
Jiangsu Key Laboratory of Integrated Traditional Chinese and Western Medicine for Prevention and Treatment of Senile Diseases Yangzhou, China.
Am J Transl Res. 2019 Dec 15;11(12):7385-7397. eCollection 2019.
Post-infectious irritable bowel syndrome (PI-IBS) is a common functional gastrointestinal (GI) disorder that occurs after acute GI infection. Recent studies showed that microRNAs were involved in the occurrence and development of IBS. Here, we elaborated the role of miR-510 in the occurrence of PI-IBS and analyzed its mechanism.
We detected the expressions of miR-510 and PRDX1 in colonic mucosal tissues by qRT-PCR, Western blot and immunohistochemistry. Furthermore, we transfected Caco-2 cells with miR-510 mimic, anti-miR-510, si-PRDX1, and control, then evaluated the cell viability and apoptosis by CCK8 assay and flow cytometry, assessed expression levels of PRDX1 by qRT-PCR and Western blot analysis, and pro-inflammatory cytokines by qRT-PCR and ELISA.
MiR-510 expression was downregulated and negatively correlated with TNF-α, whereas PRDX1 expression was upregulated in PI-IBS colonic mucosal tissues. LPS at concentrations of 5 and 10 μg/ml can significantly induce inflammatory injury in Caco-2 cells. MiR-510 overexpression aggravated the injury induced by LPS, as reflected by increased cell viability, decreased apoptosis, and less production of pro-inflammatory cytokines. miR-510 mimic transfection in cells significantly suppressed the mRNA and protein expression levels of PRDX1. Furthermore, the inflammatory injury induced by LPS was exacerbated by upregulating PRDX1 expression when miR-510 was knocked down.
MiR-510 downregulation in intestinal tissue might contribute to PI-IBS via targeting PRDX1. The results of this study will not only enrich the pathogenesis of PI-IBS but also make us understand the biological activity of miR-510 and provide important experimental basis for PI-IBS clinical treatment targeting miR-510.
感染后肠易激综合征（PI-IBS）是急性胃肠道感染后发生的一种常见的功能性胃肠（GI）疾病。最近的研究表明，微小RNA参与了肠易激综合征的发生和发展。在此，我们阐述了miR-510在PI-IBS发生中的作用并分析其机制。
我们通过qRT-PCR、蛋白质免疫印迹法和免疫组织化学检测结肠黏膜组织中miR-510和PRDX1的表达。此外，我们用miR-510模拟物、抗miR-510、si-PRDX1和对照转染Caco-2细胞，然后通过CCK8法和流式细胞术评估细胞活力和凋亡，通过qRT-PCR和蛋白质免疫印迹分析评估PRDX1的表达水平，通过qRT-PCR和酶联免疫吸附测定评估促炎细胞因子。
在PI-IBS结肠黏膜组织中，miR-510表达下调且与肿瘤坏死因子-α呈负相关，而PRDX1表达上调。浓度为5和10μg/ml的脂多糖可显著诱导Caco-2细胞发生炎症损伤。miR-510过表达加重了脂多糖诱导的损伤，表现为细胞活力增加、凋亡减少和促炎细胞因子产生减少。细胞中miR-510模拟物转染显著抑制了PRDX1的mRNA和蛋白质表达水平。此外，当miR-510被敲低时，上调PRDX1表达会加剧脂多糖诱导的炎症损伤。
肠道组织中miR-510下调可能通过靶向PRDX1导致PI-IBS。本研究结果不仅将丰富PI-IBS的发病机制，还将使我们了解miR-510的生物学活性，并为以miR-510为靶点的PI-IBS临床治疗提供重要的实验依据。
