Yu Fujun, Fan XuFei, Chen Bicheng, Dong Peihong, Zheng Jianjian
Department of Infectious Diseases, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China.
Cell Physiol Biochem. 2016;39(6):2409-2420. doi: 10.1159/000452509. Epub 2016 Nov 11.
BACKGROUND/AIMS: Wnt/β-catenin pathway is involved in liver fibrosis and microRNAs (miRNAs) are considered as key regulators of the activation of hepatic stellate cells (HSCs). A recent study showed the protective role of miR-378a-3p against cardiac fibrosis. However, whether miR-378a-3p suppresses Wnt/β-catenin pathway in liver fibrosis is largely unknown.
miR-378a-3p expression was detected in carbon tetrachloride-induced liver fibrosis and activated HSCs. Effects of miR-378a-3p overexpression on HSC activation and Wnt/β-catenin pathway were analyzed. Bioinformatic analysis was employed to identify the potential targets of miR-378a-3p. Serum miR-378a-3p expression was analyzed in patients with cirrhosis.
Reduced miR-378a-3p expression was observed in the fibrotic liver tissues and activated HSCs. Up-regulation of miR-378a-3p inhibited HSC activation including cell proliferation, α-smooth muscle actin (α-SMA) and collagen expression. Moreover, miR-378a-3p overexpression resulted in Wnt/β-catenin pathway inactivation. Luciferase reporter assays demonstrated that Wnt10a, a member of Wnt/β-catenin pathway, was confirmed to be a target of miR-378a-3p. By contrast, miR-378a-3p inhibitor contributed to HSC activation, with an increase in cell proliferation, α-SMA and collagen expression. But all these effects were blocked down by silencing of Wnt10a. Notably, sera from patients with cirrhosis contained lower levels of miR-378a-3p than sera from healthy controls. Receiver operating characteristic curve analysis suggested that serum miR-378a-3p differentiated liver cirrhosis patients from healthy controls, with an area under the curve of ROC curve of 0.916.
miR-378a-3p suppresses HSC activation, at least in part, via targeting of Wnt10a, supporting its potential utility as a novel therapeutic target for liver fibrosis.
背景/目的:Wnt/β-连环蛋白信号通路参与肝纤维化过程,而微小RNA(miRNA)被认为是肝星状细胞(HSC)激活的关键调节因子。最近一项研究显示了miR-378a-3p对心脏纤维化具有保护作用。然而,miR-378a-3p是否在肝纤维化中抑制Wnt/β-连环蛋白信号通路在很大程度上尚不清楚。
检测四氯化碳诱导的肝纤维化组织及活化的HSC中miR-378a-3p的表达。分析miR-378a-3p过表达对HSC活化及Wnt/β-连环蛋白信号通路的影响。采用生物信息学分析鉴定miR-378a-3p的潜在靶标。分析肝硬化患者血清中miR-378a-3p的表达。
在纤维化肝组织及活化的HSC中观察到miR-378a-3p表达降低。miR-378a-3p上调抑制HSC活化,包括细胞增殖、α-平滑肌肌动蛋白(α-SMA)及胶原蛋白表达。此外,miR-378a-3p过表达导致Wnt/β-连环蛋白信号通路失活。荧光素酶报告基因检测证实Wnt/β-连环蛋白信号通路成员Wnt10a是miR-378a-3p的靶标。相反,miR-378a-3p抑制剂促进HSC活化,细胞增殖、α-SMA及胶原蛋白表达增加。但所有这些效应均被Wnt10a沉默所阻断。值得注意的是,肝硬化患者血清中miR-378a-3p水平低于健康对照者。受试者工作特征曲线分析表明,血清miR-378a-3p可区分肝硬化患者与健康对照者,ROC曲线下面积为0.916。
miR-378a-3p至少部分通过靶向Wnt10a抑制HSC活化,支持其作为肝纤维化新型治疗靶点的潜在应用价值。