Atractylodis Rhizoma-Atractylodis macrocephala herbal pair restores intestinal mucosal barrier function in ulcerative colitis via activating Epac1/Rap1 pathway and inhibiting PI3K/AKT pathway

Ulcerative colitis (UC) is a persistent, diffuse intestinal inflammation that is one of the most incurable diseases in the world. Atractylodes lancea (Thunb.) DC. and Atractylodis macrocephala Koidz. are two traditional Chise medicines (TCM) recognized for their extensive history of medicinal application, commonly utilized to address gastrointestinal issues. Currently, both Atractylodis Rhizoma (AR) and Atractylodis Macrocephala (AM) have demonstrated significant effectiveness in managing UC; However, the precise mechanism by which the AR-AM herbal pair enhances intestinal mucosal healing in UC remains inadequately unclear. The therapeutic effectiveness of the ethanolic extract derived from AR-AM (EEAR-AM) was assessed using a murine UC model induced by dextran sodium sulfate (DSS). A strategy based on network pharmacology was utilized to investigate the anti-UC characteristics of EEAR-AM, focusing on identifying active constituents, predicting possible targets, and constructing a protein-protein interaction (PPI) network. Subsequently, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were performed to initially suggest the mechanisms through which EEAR-AM operates in the treatment of UC. Ultimately, the proposed molecular mechanisms associated with EEAR-AM were validated through evaluations in both the DSS-induced UC mice and Caco-2 cells. In vivo investigations demonstrated that EEAR-AM significantly mitigated weight loss induced by DSS, minimized the reduction in colon length, decreased the disease activity index (DAI) score, and influenced the spleen coefficient in UC mice. Furthermore, EEAR-AM improved the structural integrity of colon tissues, decreased the area of inflammatory infiltration, restored goblet cell numbers, increased mucin MUC2 expression, and bolstered levels of tight junction proteins. Additionally, EEAR-AM inhibited the expression of MMP-2 and MMP-9. Network pharmacology analyses suggested that EEAR-AM may address intestinal mucosal dysfunction by regulating the Epac1/Rap1 and PI3K/AKT pathways. Consequently, EEAR-AM had the potential to enhance cellular barrier integrity and reduce the discharge of inflammatory mediators. Moreover, results from western blotting indicated that EEAR-AM activated the Epac1/Rap1 pathway while downregulating the PI3K/AKT pathway in both DSS-induced UC mice and Caco-2 cells, aligning with expected outcomes from network pharmacology. This research represented the initial demonstration that the EEAR-AM herbal pair could improve the function of the intestinal mucosal barrier in UC, and the therapeutic effects might be linked to the activation of the Epac1/Rap1 pathway and the suppression of the PI3K/AKT pathway.