四氯化碳诱导小鼠肝脏纤维化的差异蛋白质组学

Differential proteome analysis of carbon tetrachlorideinduced mouse liver fibrosis

以四氯化碳(Carbon tetrachloride,CCl4)诱导小鼠肝组织纤维化为研究模型,发现并探讨纤维化肝组织与正常肝组织在蛋白质组水平上的差异。实验小鼠(C57 BL/6)随机分为两组,由橄榄油和四氯化碳诱导15周,并分别对这两组肝组织的全蛋白表达谱进行质谱检测,应用GO(Gene Ontology)功能分类分析和KEGG(Kyoto Enyoolpedia of Genes and Genomes)信号通路的富集分析方法对鉴定到的全蛋白表达谱进行差异表达分析。在对照组和实验组中,我们分别鉴定到17 382和20 486条特异性肽段,图谱平均利用率大于50%,共计鉴定到蛋白4 991种(蛋白特异性肽段个数至少为1),其中差异表达蛋白有2 135种(差异倍数大于或等于2),表达上调蛋白1 264种,下调蛋白871种。纤维化肝脏组织中与细胞外基质组成(Extracellular matrix organization)、细胞骨架组成(Cytoskeleton organization)、有机磷酸代谢(Organophosphate metabolic process)、细胞定位(Cellular localization)和细胞组分调节(Regulation of cellular component organization)相关蛋白的表达是上调的;另外,与小分子代谢(Small molecule metabolic process)、蛋白质转运(Protein transport)和有机氮化合物的代谢(Organonitrogen compound metabolic process),以及四吡咯的合成过程(Tetrapyrrole biosynthetic process)有关蛋白的表达是下调的。信号通路富集分析结果表明,纤维化与VEGF和T细胞受体信号调节通路密切相关。结果提示,纤维化的形成不仅是一个复杂的信号转导过程,更是一个炎症与免疫相互促成的结果;增强肝实质细胞的存活,降低相关信号的传递及接收都有可能对纤维化的发生和发展起到抑制效果。

To explore the differential proteome pattern in mouse fibrosis liver in comparison to wild type. Mice were fed with carbon tetrachloride or olive oil vehicle for 15 weeks. Mouse livers from both groups were collected and submitted to MS platform for proteome screening. GO （Gene Ontology） biological process and KEGG （Kyoto Enyoolpedia of Genes and Genomes） pathway enrichment analysis were used to analyze differentially expressed proteins. As the results, we identified 17 382 and 20 486 unique peptides in control and carbon tetrachloride-induced groups, respectively. A total of 4 991 proteins （at least 1 unique peptide matched） were identified, of which 2 135 were differentially expressed （≥2 fold）. In fibrosis mouse liver 1 264 proteins were up regulated and 871 proteins were down regulated. Proteins associated with DNA replication, cell cycle, ECM-receptor interaction, and splicesome were significantly increased in carbon tetrachloride- induced group. Proteins associated with small molecule metabolic process, protein transport, organonitrogen compound metabolic process, and tetrapyrrole biosynthetic processes were down regulated in carbon tetrachloride-induced mouse liver fibrosis tissue. Bioinformatics findings showed that fibrosis was closely related to the regulation of VEGF and T cell receptor signaling pathway, and further suggested that liver fibrosis was a complex signal transduction process that many biological processes such as liver metabolism, inflammation, and immune response are involved. Based this study, we can envision that protection of protein metabolism in liver parenchymal cells and blocking of inflammatory signaling transduction may be beneficial for liver fibrosis therapy.