Huanglian-Houpo extract attenuates DSS-induced UC mice by protecting intestinal mucosal barrier and regulating macrophage polarization

Huanglian-Houpo Decoction (HLHP), a classical prescription, has been used to treat gastrointestinal diseases for hundreds of years in TCM. However, the effective constituents and underlying mechanisms of HLHP in the treatment of ulcerative colitis (UC) have not been fully investigated. This study aimed to reveal the potential anti-UC mechanisms of 50% ethanol extraction of HL and HP (EHLHP), combining transcriptomes and network pharmacology, as well as the animal experiment verification. Primarily, we identified the chemical composition of EHLHP via UPLC-QE-MS analysis. A visualization network with components-targets-pathways on UC treatment were constructed using network pharmacology. And then, the transcriptomics sequencing method was applied to screen out the differentially expressed genes (DEGs) of EHLHP in the treatment of UC. The key targets and pathways of EHLHP were selected by the combination of the network pharmacology and transcriptomics results. Ultimately, the potential mechanisms of EHLHP on DSS-induced UC mice were verified. A total of 34 components of EHLHP were identified by UPLC-QE-MS analysis. Combined with the analysis of network pharmacology and transcriptomics, there were 262 DEGs between the normal group and the model group, and 151 DEGs between the model group and the EHLHP group. At the same time, there are 79 interaction paths, such as PI3K-Akt signaling pathway, MAPK signaling pathway, etc. These results indicated that the anti-UC mechanisms would be involved in calcium signaling pathway, inflammatory signaling pathway (JAK-STAT, TNF-α, cGMP-PKG) and immune regulation (IL-17, B cell receptor). After 160 mg/kg and 320 mg/kg EHLHP were given to DSS induced UC mice, these typical symptoms could be significantly alleviated, such as the decrease of DAI value and inflammation level. The IHC staining results of ZO-1, Occludin and Claudin-1 suggested that the intestinal barrier of UC mice was enhanced by EHLHP. The expression of macrophages and immune cells in F4/80+, CD11c+, Gr-1+, NK1.1+ by FCM determination indicated that EHLHP could suppress UC by immunosuppression and macrophage polarization M1 to M2. The potential mechanisms of HLHP extract on DSS-induced UC mice were revealed, by the prediction of integrated analysis of transcriptomes and network pharmacology, and subsequently animal test verification. It would provide a viable strategy to elucidate the mechanisms of TCM classical formula.