慢性束缚应激诱导IBS-D小鼠结肠组织的转录组学分析及关键通路筛选OA

Objective To screen key genes and pathways associated with increased intestinal permeability and visceral hypersensitivity in the colon tissue of chronic restraint stress-induced mouse model of diarrhea-predominant irritable bowel syndrome(IBS-D).Methods Twelve male C57BL/6 mice were randomly divided into control group and model group(n=6 each).The mice in model group were subjected to chronic restraint stress for 2 h per day over 12 consecutive days to establish the IBS-D model,while the mice in control group received no intervention and were raised under normal conditions.Body weight changes were evaluated in both groups.Visceral sensitivity was assessed by the abdominal withdrawal reflex(AWR)score in response to graded colorectal distension after sequential administration of 0.2,0.3,and 0.4 mL of normal saline.Intestinal permeability was evaluated by measuring serum fluorescence intensity at 4 h after gavage of fluorescein isothiocyanate-labeled dextran(FITC-dextran).RNA-seq was performed on mouse colon tissues using the Illumina Nova-Seq platform.Differentially expressed genes(DEGs)were screened using a cutoff of|log₂FC|>1 and P<0.05,and analyzed using GO,KEGG,and Reactome databases.Results There was no significant difference in baseline body weight of mice between the two groups[(22.98±1.66)g vs(23.53±1.15)g,P>0.05].The net body weight gain in model group was significantly lower than that in control group[(0.10±0.75)g vs(1.70±0.64)g,P<0.05].Under colorectal distension with 0.2 mL and 0.3 mL of saline,AWR scores were sig-nificantly higher in the model group than in the control group(both P<0.001).Furthermore,the serum FITC-dextran concentration in model group was significantly elevated compared with control group(P<0.01).RNA-seq identified 273 DEGs,including 97 signifi-cantly up-regulated genes and 176 significantly down-regulated genes.GO enrichment results showed that the DEGs were mainly enriched in functions related to immune response,antigen recognition,and the extracellular region.KEGG enrichment results suggested they were involved in intestinal barrier maintenance and visceral sensory signaling.Reactome analysis showed that DEGs were significantly enriched in immune receptor activation and calcium signaling pathways.Conclusion Chronic restraint stress induced significant transcriptional changes in the colonic transcriptome of IBS-D model mice.These changes may contribute to the pathogenesis of IBS-D by activating intestinal immune inflammatory responses,disrupting mucus barrier integrity,and enhancing visceral sensory neural transmission.