Wumei pills attenuates 5-fluorouracil-induced intestinal mucositis through Toll-like receptor 4/myeloid differentiation factor 88/nuclear factor-κB pathway and microbiota regulation

BACKGROUND: Radiotherapy and chemotherapy can kill tumor cells and improve the survival rate of cancer patients. However, they can also damage normal cells and cause serious intestinal toxicity, leading to gastrointestinal mucositis[1]. Traditional Chinese medicine is effective in improving the side effects of chemotherapy. Wumei pills (WMP) was originally documented in the Treatise on Exogenous Febrile Diseases. It has a significant effect on chronic diarrhea and other gastrointestinal diseases, but it is not clear whether it affects chemotherapy-induced intestinal mucositis (CIM). AIM: To explore the potential mechanism of WMP in the treatment of CIM through experimental research. METHODS: We used an intraperitoneal injection of 5-fluorouracil (5-Fu) to establish a CIM mouse model and an oral gavage of WMP decoction (11325 and 22650 mg/kg) to evaluate the efficacy of WMP in CIM. We evaluated the effect of WMP on CIM by observing the general conditions of the mice (body weight, food intake, spleen weight, diarrhea score, and hematoxylin and eosin stained tissues). The expression of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), IL-1β, and myeloperoxidase (MPO), as well as the Toll-like receptor 4/myeloid differentiation factor 88/nuclear factor-κB (TLR4/MyD88/NF-κB) signaling pathway proteins and tight junction proteins (zonula occludens-1, claudin-1, E-cadherin, and mucin-2) was determined. Furthermore, intestinal permeability, intestinal flora, and the levels of short-chain fatty acids (SCFA) were also assessed. RESULTS: WMP effectively improved the body weight, spleen weight, food intake, diarrhea score, and inflammatory status of the mice with intestinal mucositis, which preliminarily confirmed the efficacy of WMP in CIM. Further experiments showed that in addition to reducing the levels of TNF-α, IL-1β, IL-6, and MPO and inhibiting the expression of the TLR4/MyD88/NF-κB pathway proteins, WMP also repaired the integrity of the mucosal barrier of mice, regulated the intestinal flora, and increased the levels of SCFA (such as butyric acid). CONCLUSION: WMP can play a therapeutic role in CIM by alleviating inflammation, restoring the mucosal barrier, and regulating gut microbiota.