Analysis of Colon Transcriptomes in a Porcine Model of Dextran Sodium Sulfate (DSS)-Induced Ulcerative Colitis

Dextran sodium sulfate (DSS) was used to induce ulcerative colitis in a porcine model to investigate the transcriptional responses in inflamed colonic tissue. Eleven pigs were divided into two groups, of which five pigs were administered an oral dose of DSS daily for five days, whereas six non-treated pigs served as a control group. Differences in transcript expression between treated and control pigs identified 425 down-regulated and 780 up-regulated mRNAs in response to DSS treatment. Fifty-nine differentially expressed miRNAs were also identified, comprising 20 up-regulated and 39 down-regulated miRNAs. The top enrichment KEGG pathways for the up-regulated genes were breast cancer (ssc05224), gastric cancer (ssc05226), focal adhesion (ssc04510), and the PI3K-Akt signaling pathway (ssc04151). The top gene ontology terms for the up-regulated genes were blood vessel development (GO:0001568), extracellular matrix and external encapsulating structure (GO:0031012). Protein-protein interaction network analysis identified three hub genes, including LOXL1, MFAP2, and FSTL3. Seventeen high-confidence miRNA-mRNA pairs were recognized, and two genes (CD101 and AVL9) have been confirmed as targets for ssc-miR-24-3p by dual-luciferase reporter assay. Our study provides a better understanding of the key roles of mRNAs and miRNAs in regulating DSS-induced colitis in pigs and defines sets of coding and non-coding RNA transcripts, which may serve as intervention targets or biomarkers for ulcerative colitis.