Huang Ru, Deng Juan, Wang Ke-Qi, Zhu Chang-Peng, Ding Chen-Hong, Chen Fei, Zhang Xin, Xie Wei-Fen
Department of Gastroenterology, Changzheng Hospital, Naval Medical University, Shanghai, China.
Department of Gastroenterology, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, China.
Liver Int. 2025 Sep;45(9):e70227. doi: 10.1111/liv.70227.
BACKGROUND & AIMS: Transforming growth factor (TGF)-β signalling plays an indispensable role in promoting the activation of hepatic stellate cells and inducing epithelial-mesenchymal transition of hepatocytes during liver fibrosis. Liver sinusoidal endothelial cells (LSECs) undergo capillarisation and promote inflammatory responses following liver injury. Here, we investigated the role of TGF-β signalling in LSECs during liver fibrosis.
Single-cell RNA-sequencing (scRNA-seq) datasets from healthy individuals and patients with cirrhosis were analysed to evaluate the expression of TGF-β signalling related genes. Endothelial cell-specific Tgfbr2-knockout mice were generated and experimental liver fibrosis was induced by carbon tetrachloride injection or choline-deficient high-fat diet. Liver fibrosis was evaluated by qPCR, western blotting, histology and immunostaining. Primary LSECs were isolated and gene expression was analysed by RNA sequencing. Hepatic inflammation was assessed by qPCR, immunostaining and flow cytometry.
ScRNA-seq analysis based on GSE136103 showed TGFBR2 is elevated in LSECs from cirrhotic patients compared to healthy controls. LSEC-specific Tgfbr2 depletion ameliorated injury-induced LSEC capillarisation and endothelial-to-mesenchymal transition. RNA sequencing revealed that Tgfbr2 deficiency downregulated chemokine expression and reshaped angiocrine signalling in LSECs. Endothelial-specific Tgfbr2 deletion inhibited pro-inflammatory monocyte recruitment and attenuated hepatic inflammation during liver fibrosis. Furthermore, Tgfbr2 deletion in LSECs inhibited macrophage chemotaxis in vitro.
Endothelial TGF-β signalling aggravates injury-induced liver fibrosis by promoting LSECs capillarisation, EndMT and proinflammatory monocyte recruitment. These findings show the potential of targeting TGFBR2 in LSECs to control liver fibrotic diseases.
在肝纤维化过程中，转化生长因子（TGF）-β信号通路在促进肝星状细胞活化及诱导肝细胞上皮-间质转化中发挥不可或缺的作用。肝窦内皮细胞（LSEC）在肝损伤后会发生毛细血管化并促进炎症反应。在此，我们研究了TGF-β信号通路在肝纤维化过程中对LSEC的作用。
分析来自健康个体和肝硬化患者的单细胞RNA测序（scRNA-seq）数据集，以评估TGF-β信号通路相关基因的表达。构建内皮细胞特异性Tgfbr2基因敲除小鼠，通过注射四氯化碳或给予胆碱缺乏的高脂饮食诱导实验性肝纤维化。通过qPCR、蛋白质印迹、组织学和免疫染色评估肝纤维化。分离原代LSEC并通过RNA测序分析基因表达。通过qPCR、免疫染色和流式细胞术评估肝脏炎症。
基于GSE136103的scRNA-seq分析显示，与健康对照相比，肝硬化患者LSEC中TGFBR2表达升高。LSEC特异性Tgfbr2缺失改善了损伤诱导的LSEC毛细血管化和内皮-间质转化。RNA测序显示，Tgfbr2缺乏下调了LSEC中的趋化因子表达并重塑了血管分泌信号。内皮特异性Tgfbr2缺失抑制了促炎单核细胞募集，并减轻了肝纤维化过程中的肝脏炎症。此外，LSEC中Tgfbr2缺失在体外抑制了巨噬细胞趋化性。
内皮TGF-β信号通路通过促进LSEC毛细血管化、内皮-间质转化和促炎单核细胞募集加重损伤诱导的肝纤维化。这些发现表明，靶向LSEC中的TGFBR2对控制肝纤维化疾病具有潜在作用。
