Objective To investigate the therapeutic effect and mechanism of Zhizhu Kuanzhong Capsule (枳术宽中胶囊, ZZKZ) on dextran sulfate sodium (DSS)-induced ulcerative colitis (UC) and associated depressive-like behaviors. Methods The main components in ZZKZ were analyzed using UPLC-LTQ/Orbitrap-MS. UC model was established by freely drinking 3.5% DSS solution in mice, and drug intervention was given for 7 d. Hematoxylin-eosin (HE) and Alcian blue-periodic acid Schiff (AB-PAS) staining were used to evaluate the pathological damage and mucus secretion of colon tissue. Depressive like behavior was evaluated using open field experiments and sugar water preference experiments. 16S rRNA sequencing and serum untargeted metabolomics were used to analyze changes in gut microbiota and serum metabolites. Network pharmacology was used to predict targets and pathways, which were validated through molecular docking, molecular dynamics simulation, qRT-PCR and Western blotting experiments. Results Compared with model group, ZZKZ significantly reduced colon shortening in UC mice (P < 0.05, 0.01), decreased disease activity index (DAI) score (P < 0.01), increased total distance, average exercise speed in open field experiments and sugar preference index (P < 0.05, 0.01), reduced the expressions of inflammatory factors in colon and brain tissues (P < 0.05, 0.01), and alleviated intestinal tissue pathological damage and hippocampal neuron damage (P < 0.01). 16S rRNA sequencing results showed that ZZKZ could reduce the abundance of harmful bacteria, increase the abundance of beneficial bacteria, and reverse the imbalance of gut microbiota. The results of serum non-targeted metabolomics analysis showed that ZZKZ could regulate metabolic pathways, reverse lipid, tryptophan and bile acid metabolism disorders. Network pharmacology analysis predicted that Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) was related pathway, ursolic acid, atractylenolide I, hesperetin and isorhamnetin in ZZKZ showed significant binding affinity with their target proteins, which may be the main active ingredients for their therapeutic effects. Western blotting results showed that compared with model group, ZZKZ significantly upregulated the expressions of zonula occludin-1 (ZO-1), Occludin and Claudin-1 in colon of UC mice (P < 0.05, 0.01), and inhibited the phosphorylation of JAK2 and STAT3 (P < 0.05). Conclusion ZZKZ may alleviate UC and associated depressive like behavior by regulating gut microbiota, metabolic pathways and inhibiting JAK2/STAT3 pathway.

Zhizhu Kuanzhong Capsule  /  ulcerative colitis  /  depression-like behaviors  /  gut-brain axis  /  JAK2/STAT3 pathway  /  atractylenolide I  /  hesperetin  /  ursolic acid  /  isorhamnetin