Abstract: 【Objective】 The purpose of this study was to rapidly induce enteritis in Bama pigs via dextran sulfate sodium (DSS) gavage and investigate the effects of gut-liver axis dysfunction on liver function and gene expression,aiming to provide a theoretical basis for the prevention and control of gut-liver related diseases in animal husbandry，and at the same time,provide scientific evidence for the transformation and application of this model for human hepatitis. 【Method】 Sixteen 120-day-old Bama boars were randomly divided into Control and DSS groups,with 8 boars in each group.The boars in DSS group were intragastrically administered with DSS solution (1.25 g/kg BW) for 6 consecutive days,while the boars in Control group were given the same volume of pure water by intragastric administration.On the 7th day of the experiment,serum and liver samples were collected after the animals were slaughtered.The pathological changes of liver tissues were observed through HE staining,immunofluorescence staining and Masson staining,and the activities of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in serum were detected.Transcriptome sequencing was performed on liver samples to screen for differentially expressed genes (DEGs) induced by DSS and to identify the genes that were differentially expressed in liver.GO function,KEGG pathway and GSEA enrichment analyses were performed.The expression of liver inflammatory and fibrotic-related genes were detected using Real-time quantitative PCR. 【Result】 HE staining showed that there was an increase in immune cell infiltration and disordered liver tissue structure in DSS group.Compared with Control group,the AST activity of serum in DSS group was significantly increased (P＜0.05),while the ALT activity showed no significant change (P＞0.05).Transcriptome analysis identified 2 456 DEGs (1 153 upregulated and 1 303 downregulated).GO function annotation showed that the DEGs were significantly enriched in biological processes such as inflammatory response,fatty acid metabolism,and cholesterol metabolism.KEGG pathway enrichment analysis revealed that the DEGs were mainly significantly enriched in disorders of bile acid metabolism,inhibition of the PPAR signaling pathway,and activation of the NF-κB signaling pathway,etc.GSEA analysis revealed that the upregulated pathways were mostly related to inflammatory responses (IL-6/JAK/STAT3 signaling pathway,TNF-α/NF-κB signaling axis,etc.),while the downregulated pathways mainly involved metabolic functions (fatty acid metabolism,bile acid metabolism,etc.).The results of immunofluorescence staining and Real-time quantitative PCR showed that compared with Control group,the infiltration of CD45^＋ cells and collagen deposition of liver in DSS group were significantly increased,and the expression of pro-inflammatory genes TNF-α,IL-6, CXCL2,CXCL10 and MCP1，and pro-fibrotic genes COL3A1 and TGF-β were significantly increased (P＜0.05). 【Conclusion】 DSS gavage could rapidly induce inflammation in porcine liver,leading to liver metabolic dysfunction and impaired nutrient absorption.The results provided a theoretical basis for basic research on liver diseases in livestock and poultry and for the translation of medical models of human hepatitis.

Key words: pig; liver; dextran sulfate sodium (DSS); RNA-Seq; inflammation; fibrosis