The study aimed to clarify the role and molecular mechanism of glutamate-cysteine ligase catalytic subunit (GCLC) in modulating Hepatitis C virus (HCV)-related liver fibrosis. Twenty patients with HCV-related liver fibrosis and 15 healthy controls were enrolled. Differentially expressed plasma mRNAs were detected by digital gene expression profile analysis and validated by qRT-PCR. Hepatic histopathology was observed by H&E and Masson stained liver sections. The mRNA and protein expression of GCLC, endoplasmic reticulum (ER) stress markers, and inflammatory and fibrogenic factors were detected in liver tissues from patients with HCV-related hepatic fibrosis and HCV core protein-expressing LX-2. The GCLC-overexpressing LX-2 were established by transfecting puc19-GCLC plasmid. Then, glutathione and reactive oxygen species (ROS) levels were measured respectively by spectrophotometric diagnostic kit and dihydrodichlorofluorescein diacetate kit. GCLC were dramatically down-regulated in HCV-related fibrotic livers and activated HSCs, which companied with up-regulation of ER stress-related genes, including inositol-requiring 1 (IRE1) and glucose-regulated protein 78 (GRP78). Also, the proinflammatory and profibrogenic gene, including nuclear factor kappa B (NF-κB), tumor necrosis factor α (TNFα), and transforming growth factor 1(TGFβ1), was highly upregulated. Overexpression of GCLC in hepatic stellate cells could suppress α-SMA and collagen I expression, produce hepatic GSH and reduce ROS, and down-regulate IRE1, GRP78, NF-κB, TNF-α, and TGFβ1 expression. GCLC was a negative regulatory factor in the development of HCV-related liver fibrosis and might be a potential therapeutic target for liver fibrosis.

该研究旨在阐明谷氨酸-半胱氨酸连接酶催化亚基（GCLC）在调节丙型肝炎病毒（HCV）相关的肝纤维化中的作用和分子机制。招募了20例HCV相关肝纤维化患者和15名健康对照。通过数字基因表达谱分析检测差异表达的血浆mRNA，并通过qRT-PCR进行验证。通过H＆E和Masson染色的肝脏切片观察到肝组织病理学。在HCV相关性肝纤维化和表达HCV核心蛋白的LX-2患者的肝组织中检测到GCLC，内质网（ER）应激标志物以及炎症和纤维化因子的mRNA和蛋白表达。通过转染puc19-GCLC质粒建立了GCLC过表达的LX-2。然后，谷胱甘肽和活性氧（ROS）的水平分别通过分光光度法诊断试剂盒和二氢二氯荧光素二乙酸酯试剂盒测量。GCLC在HCV相关的纤维化肝脏和活化的HSC中显着下调，并伴有ER应激相关基因的上调，包括需要肌醇1（IRE1）和葡萄糖调节蛋白78（GRP78）。另外，包括核因子κB（NF-κB），肿瘤坏死因子α（TNFα）和转化生长因子1（TGFβ1）在内的促炎和纤维化原基因也被上调。GCLC在肝星状细胞中的过表达可以抑制α-SMA和胶原I的表达，产生肝GSH并降低ROS，并下调IRE1，GRP78，NF-κB，TNF-α和TGFβ1的表达。