湿热证患者肠道菌群加重肠黏膜炎性免疫反应促大肠癌发生的作用机制  

Mechanism of gut microbiota promoting colorectal cancer through aggravating intestinal mucosal inflammatory immune response in patients with damp‑heat syndrome

作　　者：朱祥祥 侯新新 张兆洲 赵玲[1] ZHU Xiangxiang;HOU Xinxin;ZHANG Zhaozhou;ZHAO Ling(School of Integrative Medicine,Shanghai University of Traditional Chinese Medicine,Shanghai 201203,China)

机构地区：[1]上海中医药大学中西医结合学院,上海201203

出　　处：《上海中医药杂志》2024年第3期65-71,共7页Shanghai Journal of Traditional Chinese Medicine

基　　金：国家自然科学基金项目(82104955,81830120);中国博士后科学基金项目(2022M712154);上海市科技创新行动计划启明星项目(22QA1408700)。

摘　　要：目的探讨湿热证大肠癌患者肠道菌促进肠癌发生的机制。方法健康雌性SPF级C57BL/6J小鼠随机分为3组,即健康对照粪菌移植组(HC-FMT)、湿热证大肠癌粪菌移植组(DHS-FMT)及非湿热证大肠癌粪菌移植组(Non_DHS-FMT),每组10只。各组小鼠均构建为伪无菌小鼠,再分别移植健康对照人群、湿热证大肠癌及非湿热证大肠癌患者粪便菌液;同时采用氧化偶氮甲烷(AOM)联合葡聚糖硫酸钠(DSS)诱导小鼠肠癌发生。干预13周后,采用16S rRNA法检测粪菌移植后各组小鼠肠道菌群结构;观察小鼠结肠肿瘤数目及结肠病理改变;流式细胞术及实时荧光定量逆转录聚合酶链式反应(RT-qPCR)法检测结肠组织免疫细胞亚群及细胞因子表达水平变化。结果粪菌移植后,各组小鼠肠道菌群结构具有明显差异。与HCFMT比较,DHS-FMT小鼠结肠肿瘤数目增多(P<0.05),结肠浸润免疫细胞(P<0.05)、树突状细胞(DC)(P<0.05)、CD4+T细胞(P<0.05)增多;Th1型转录因子T盒转录因子21(Tbx21)及细胞因子γ干扰素(IFN-γ)mRNA(P<0.05)表达水平升高;Th17型转录因子RAR相关孤儿受体C(Rorc)及细胞因子白介素-17a(IL-17a)mRNA(P<0.05)表达水平升高。结论湿热证大肠癌患者肠道菌群可促进AOM/DSS小鼠肿瘤形成、促进固有层免疫细胞浸润、诱导Th1及Th17型促炎性免疫反应、加重肠黏膜炎症,进而促进大肠癌的发生。Objective To investigate the underlying tumorigenesis mechanism of damp-heat syndrome(DHS)-related gut bacteria in colorectal cancer(CRC)initiation.Methods Fecal microbiota from DHS patients of CRC,Non-DHS patients of CRC and healthy control(HC)volunteers were transplanted to pseudo-germ-free mice respectively.Simultaneously,azomethane oxide(AOM)/dextran sodium sulfate(DSS)was used to induce CRC in mice.After 13 weeks of intervention,16S rRNA was performed to analyze the gut microbiota structure in three groups of fecal microbiota transplantation(FMT)mice.The tumor numbers and pathological changes were observed.The changes of immune cell subsets and cytokines in colon tissue were detected by flow cytometry and real-time quantification PCR(RT-qPCR).Results After FMT,the gut microbiota structure of three groups of mice were significantly different.In mice,compared with HC-FMT group,the tumor numbers were increased in DHS-FMT group(P<0.05).The infiltrating immune cells(P<0.05),DC cells(P<0.05),CD4+T cells(P<0.05)in colon lamina propria of DHS-FMT group were significantly increased.Compared with HC-FMT group,the mRNA expression levels of Th1-type transcription factor Tbx21 and cytokine IFN-γ(P<0.05)as well as the mRNA expression levels of Th17-type transcription factor Rorc and cytokine IL-17a(P<0.05)were increased in DHS-FMT group.Conclusion Gut bacteria from CRC patients with DHS can promote tumorigenesis in AOM/DSS mice,increase lamina propria immune cell infiltration,induce Th1 and Th17 pro-inflammatory immune responses,aggravate colonic mucosal inflammation,and then promote the occurrence of colorectal cancer.

关 键 词：结直肠癌 湿热证 肠道菌群 黏膜免疫 炎症反应 病理 作用机制 中医证候 

分 类 号：R273[医药卫生—中西医结合]