UNASSIGNED: Small interfering RNA-mediated knockdown of GPR176 was used to assess the in vitro function of GPR176 in HSCs and in precision cut liver slices (PCLS). The in vivo role of GPR176 was assessed using the carbon tetrachloride (CCl4) and common bile duct ligation (BDL) models in wild-type and GPR176 knockout mice. GPR176 in human CLD was assessed by immunohistochemistry of diseased human livers and RNA expression analysis in human primary HSCs and transcriptomic data sets.
UNASSIGNED: We identified Gpr176, an orphan G-protein coupled receptor, as an HSC-enriched activation associated gene. In vitro, Gpr176 is strongly induced upon culture-induced and hepatocyte-damage-induced activation of primary HSCs. Knockdown of GPR176 in primary mouse HSCs or PCLS cultures resulted in reduced fibrogenic characteristics. Absence of GPR176 did not influence liver homeostasis, but Gpr176-/- mice developed less severe fibrosis in CCl4 and BDL fibrosis models. In humans, GPR176 expression was correlated with in vitro HSC activation and with fibrosis stage in patients with CLD.
UNASSIGNED: GPR176 is a functional protein during liver fibrosis and reducing its activity attenuates fibrogenesis. These results highlight the potential of GPR176 as an HSC-specific antifibrotic candidate to treat CLD.
UNASSIGNED: The lack of effective antifibrotic drugs is partly attributed to the insufficient knowledge about the mechanisms involved in the development of liver fibrosis. We demonstrate that the G-protein coupled receptor GPR176 contributes to fibrosis development. Since GPR176 is specifically expressed on the membrane of activated hepatic stellate cells and is linked with fibrosis progression in humans, it opens new avenues for the development of targeted interventions.
■使用小干扰RNA介导的GPR176敲低来评估GPR176在HSC和精确切割肝切片(PCLS)中的体外功能。在野生型和GPR176敲除小鼠中使用四氯化碳(CCl4)和胆总管结扎(BDL)模型评估GPR176的体内作用。通过患病的人肝脏的免疫组织化学和人原代HSC和转录组数据集中的RNA表达分析来评估人CLD中的GPR176。
■我们鉴定了Gpr176,一种孤儿G蛋白偶联受体,作为富含HSC的活化相关基因。体外,Gpr176在培养诱导和肝细胞损伤诱导的原代HSC活化后被强烈诱导。在原代小鼠HSC或PCLS培养物中敲除GPR176导致纤维化特征降低。缺乏GPR176不会影响肝脏稳态,但是Gpr176-/-小鼠在CCl4和BDL纤维化模型中发生的纤维化程度较低。在人类中,GPR176的表达与CLD患者的体外HSC活化和纤维化分期相关。
■GPR176是肝纤维化过程中的功能性蛋白,降低其活性可减弱纤维化。这些结果突出了GPR176作为HSC特异性抗纤维化候选物治疗CLD的潜力。
■缺乏有效的抗纤维化药物部分归因于对肝纤维化发展机制的了解不足。我们证明G蛋白偶联受体GPR176有助于纤维化发展。由于GPR176在活化的肝星状细胞膜上特异性表达,并且与人类的纤维化进展有关,它为制定有针对性的干预措施开辟了新的途径。