METHODS: Our previous research indicated that downregulating the ICOSL/ICOS could partially alleviate liver fibrosis. In this study, we established a schistosomiasis infection model in C57BL/6 and ICOSL knockout (KO) mice, and the liver pathology changes were observed at various weeks postinfection (wpi) using hematoxylin and eosin and Masson\'s trichrome staining. Within the first 4 wpi, no significant liver abnormalities were observed. However, mice exhibited evident egg granulomas and fibrosis in their livers at 7 wpi. Notably, ICOSL-KO mice had significantly smaller pathological variations compared with simultaneously infected C57BL/6 mice. To investigate the impact of lncRNAs on schistosomiasis-associated liver fibrosis, quantitative real-time polymerase chain reaction (RT-qPCR) was used to monitor the dynamic changes of lncRNAs in hepatic stellate cells of infected mice.
RESULTS: The results demonstrated that lncRNA-H19, -MALAT1, -PVT1, -P21 and -GAS5 all participated in liver fibrosis formation after schistosome infection. In addition, ICOSL-KO mice exhibited significantly inhibited expression of lncRNA-H19, -MALAT1 and -PVT1 after 7 wpi. In contrast, they showed enhanced expression of lncRNA-P21 and -GAS5 compared with C57BL/6 mice, influencing liver fibrosis development. Furthermore, small interfering RNA transfection (siRNA) in JS-1 cells in vitro confirmed that lncRNA-H19, -MALAT1, and -PVT1 promoted liver fibrosis, whereas lncRNA-P21 and -GAS5 had the opposite effect on key fibrotic molecules, including α- smooth muscle actin and collagen I expression.
CONCLUSIONS: This study uncovers that ICOSL/ICOS may play a role in activating hepatic stellate cells and promoting liver fibrosis in mice infected with Schistosoma japonicum by dynamically regulating the expression of specific lncRNAs. These findings offer potential therapeutic targets for schistosomiasis-associated liver fibrosis.
方法:我们先前的研究表明下调ICOSL/ICOS可以部分缓解肝纤维化。在这项研究中,我们在C57BL/6和ICOSL基因敲除(KO)小鼠中建立了血吸虫病感染模型,并在感染后(wpi)使用苏木精和伊红和Masson三色染色观察肝脏病理学变化。在前4wpi内,未观察到明显的肝脏异常。然而,小鼠在7wpi时表现出明显的卵肉芽肿和肝脏纤维化。值得注意的是,与同时感染的C57BL/6小鼠相比,ICOSL-KO小鼠的病理变异明显较小。探讨lncRNAs对血吸虫病相关肝纤维化的影响,定量实时聚合酶链反应(RT-qPCR)用于监测感染小鼠肝星状细胞中lncRNAs的动态变化。
结果:结果表明,lncRNA-H19、-MALAT1、-PVT1、-P21和-GAS5均参与了血吸虫感染后肝纤维化的形成。此外,ICOSL-KO小鼠在7wpi后表现出显著抑制lncRNA-H19、-MALAT1和-PVT1的表达。相比之下,与C57BL/6小鼠相比,它们显示lncRNA-P21和-GAS5的表达增强,影响肝纤维化发展。此外,小干扰RNA转染(siRNA)在体外JS-1细胞中证实lncRNA-H19,-MALAT1和-PVT1促进肝纤维化,而lncRNA-P21和-GAS5对关键纤维化分子有相反的作用,包括α-平滑肌肌动蛋白和胶原蛋白I的表达。
结论:本研究发现ICOSL/ICOS可能通过动态调控特异性lncRNAs的表达,激活日本血吸虫感染小鼠的肝星状细胞,促进肝纤维化。这些发现为血吸虫病相关肝纤维化提供了潜在的治疗靶点。