Department of Gastrointestinal surgery, The Second Affiliated Hospital, Jiangxi Medical College, Nanchang University, Nanchang, Jiangxi Province, 330006, PR China; Department of Hepatobiliary surgery, The Second Affiliated Hospital, Jiangxi Medical College, Nanchang University, Nanchang, Jiangxi Province, 330006, PR China.
Department of Gastrointestinal surgery, The Second Affiliated Hospital, Jiangxi Medical College, Nanchang University, Nanchang, Jiangxi Province, 330006, PR China.
Int Immunopharmacol. 2024 Dec 5;142(Pt B):113230. doi: 10.1016/j.intimp.2024.113230. Epub 2024 Sep 24.
Ulcerative colitis (UC) is a growing global health concern, with current treatments facing challenges like drug dependence and side effects. Fresh bamboo juice (FBJ), known for its antimicrobial and potential immune-modulating properties, has shown promise as a natural therapeutic agent. The present study aimed to explore the protective effects of FBJ against colitis and further analyze the changes of gut microbiota composition, metabolite profiles, and underlying immune mechanisms.
A colitis model in mice was established using DSS to investigate the effectiveness of FBJ. Intestinal tissue and fecal samples were also collected for 16S rRNA gene sequencing and liquid chromatography-mass spectrometry (LC-MS) analysis. Additionally, immunofluorescence and flow cytometry were employed to detect the proliferation and function of group 2 innate lymphoid cells (ILC2). Enzyme-linked immunosorbent assay (ELISA) was used to measure the cytokines secreted by immune cells.
FBJ demonstrated significant therapeutic effects against DSS-induced colitis in mice. At the genus level, the abundance of Bacteroides, Akkermansia and unassigned bacteria in the bamboo juice group increased compared with the DSS group. In contrast, the abundance of Alloprevotella, Lactobacillus, Lachnospiraceae_NK4A136_group and Ruminococcaceae_UCG-014 significantly decreased. FBJ partially restored the balance of gut microbiota, as evidenced by the increased levels of beneficial bacteria. Metabolome analysis revealed significant alterations in fecal metabolites, including 3-Hydroxypyridine, Pyridoxine, SM(d18:1/16:0), and DL-Methionine sulfoxide were remarkably altered. Dysregulation of pathways such as Vitamin B6 metabolism, sphingolipid metabolism, and tyrosine metabolism was observed, which may contribute to protection against colitis. Flow cytometry and immunofluorescence showed a significant reduction in the proportion of ILC2 cells following FBJ treatment in the DSS group (1.82 % v.s. 3.18 %, P < 0.05). ELISA showed that the FBJ group had lower levels of IL-5, IL-6, IL-10, IL-13, IL-33, TNF-α, IFN-γ in intestinal tissue.
Our findings demonstrate that FBJ exerts a protective effect against colitis, primarily by modulating the intestinal flora and metabolite profiles in mice with colitis. Furthermore, the observed alterations in bacterial flora and metabolites likely affect ILC2 function and cytokine production, thereby mediating the protective effects against colitis through modulation of the immune system.
溃疡性结肠炎（UC）是一个日益严重的全球健康问题，目前的治疗方法面临药物依赖和副作用等挑战。鲜竹沥（FBJ）具有抗菌和潜在的免疫调节特性，已被证明是一种有前途的天然治疗剂。本研究旨在探讨 FBJ 对结肠炎的保护作用，并进一步分析肠道微生物群落组成、代谢物谱和潜在免疫机制的变化。
使用 DSS 建立结肠炎小鼠模型，以研究 FBJ 的有效性。还收集肠组织和粪便样本进行 16S rRNA 基因测序和液相色谱-质谱（LC-MS）分析。此外，免疫荧光和流式细胞术用于检测 2 型固有淋巴细胞（ILC2）的增殖和功能。酶联免疫吸附测定（ELISA）用于测量免疫细胞分泌的细胞因子。
FBJ 对 DSS 诱导的结肠炎小鼠具有显著的治疗作用。在属水平上，与 DSS 组相比，FBJ 组中拟杆菌属、阿克曼氏菌属和未分类菌属的丰度增加。相反，Alloprevotella、Lactobacillus、Lachnospiraceae_NK4A136_group 和 Ruminococcaceae_UCG-014 的丰度显著降低。FBJ 部分恢复了肠道微生物群落的平衡，这表现在有益细菌水平的增加。代谢组学分析显示粪便代谢物发生显著变化，包括 3-羟基吡啶、吡哆醇、SM(d18:1/16:0)和 DL-甲硫氨酸亚砜。观察到维生素 B6 代谢、鞘脂代谢和酪氨酸代谢等途径的失调，这可能有助于预防结肠炎。流式细胞术和免疫荧光显示，FBJ 处理后 DSS 组中 ILC2 细胞的比例显著降低（1.82% v.s. 3.18%，P < 0.05）。ELISA 显示 FBJ 组肠组织中 IL-5、IL-6、IL-10、IL-13、IL-33、TNF-α和 IFN-γ水平较低。
我们的研究结果表明，FBJ 对结肠炎具有保护作用，主要通过调节结肠炎小鼠的肠道菌群和代谢物谱。此外，观察到的细菌群落和代谢物的变化可能影响 ILC2 功能和细胞因子的产生，从而通过调节免疫系统介导对结肠炎的保护作用。
