摘要
Abstract
Objective To investigate the mechanism by which dendrobine(Den)ameliorates irritable bowel syndrome(IBS).Methods Male SD rats were used to establish an IBS model induced by senna leaf[6 g/(kg·d)]combined with restraint stress,and swimming fatigue.They were randomly divided into three groups:Control group,IBS model group,and Dendrobine treatment group[IBS+Den group,60 mg/(kg·d)],each with 8 rats.Symptom improvement was assessed by evaluating body weight changes,abdominal wall withdrawal reflex(AWR)scores,loose stool index,and loose stool frequency.Inflammatory scores and goblet cell counts in rat colon tissues were analyzed using hematoxylin-eosin(HE)staining and Alcian blue-periodic acid-Schiff(AB-PAS)staining.Serum levels of inflammatory cytokines tumor necrosis factor-α(TNF-α),interleukin-6(IL-6),and interleukin-1β(IL-1β)were measured to assess systemic inflammation.The differentially expressed proteins were screened via proteomics analysis based on data-independent acquisition technology,combined with Gene Ontology(GO),Kyoto Encyclopedia of Genes and Genomes(KEGG),and Gene Set Enrichment Analysis(GSEA)to reveal key pathways.The regulatory mechanism of the mitogen-activated protein kinase(MAPK)signaling pathway was validated via RT-qPCR,Western blot,and molecular docking.Results Compared with the IBS group,rats in the IBS+Den group exhibited weight recovery,reduced AWR scores at 60 mmHg(1 mmHg=0.133 kPa)pressure,and decreased loose stool index and loose stool frequency(all P＜0.05),and lower serum TNF-α,IL-6,and IL-1β levels(all P＜0.05).HE and AB-PAS staining revealed that,compared with the IBS group,the IBS+Den group exhibited reduced colonic tissue inflammation scores and increased relative goblet cell area(both P＜0.05).Proteomic analysis of IBS rat colon tissue identified 405 differentially expressed proteins(222 upregulated,and 183 downregulated).GO analysis indicated key biological processes involving regulation of chemical synapse transmission,regulation of atypical glutamate receptors,and intracellular homeostasis.KEGG analysis revealed significant regulation of MAPK,IL-17,and AMP-dependent protein kinase(AMPK)signaling pathways.RT-qPCR and Western blotting experiments confirmed that Den inhibited p38 MAPK and p44/42 MAPK phosphorylation(both P＜0.05).Molecular docking indicated a binding affinity of-6.5 kcal/mol with the MAPK1 protein,suggesting direct targeting.Conclusion Den exerts multi-target therapeutic effects by inhibiting MAPK signaling pathway phosphorylation,thereby exerting anti-inflammatory actions,repairing the intestinal barrier,and improving visceral sensitivity.关键词
石斛碱/肠易激综合征/蛋白组学/MAPK信号通路/肠道屏障Key words
Dendrobine/Irritable bowel syndrome/Proteomics/MAPK signaling pathway/Intestinal barrier
