肠道菌群紊乱与疾病教材教学课件.ppt

肠道微生物识别 microbial recognition 一些受体可感受细菌细胞壁、细胞核成分。 结直肠黏膜通过模式识别受体（pattern recognition receptors PRRs） Toll-like receptors ，TLRs；nucleotide-binding domain leucine-rich repeat proteins (NLR; also known as Nod-like receptors)；retinoic acid inducible gene-I like RNA helicases (RLH), C-type lectin receptors (CLR)。 研究最为深入和广泛的是TLRs。 TLRs在细菌-炎症-肿瘤过程中起重要的介导作用  The innate immune receptor Nod1 protects the intestine frominflammation-induced tumorigenesis Chen et al. Nod1 deficiency results in increased inflammation-induced colon tumors Nod1 and the Apc tumor suppressor cooperate in colitis-associated tumorigenesis Severity of chemically-induced colitis is increased with Nod1 deficiency Nod1 deficiency results in increased proinflammatory mediator production and increased intestinal epithelial proliferation The gut microbiota contributes to increased colitis-associated tumorigenesis with Nod1 deficiency Cancer Res. 2008 December 15; 68(24): 10060–10067. Roles for Inflammation and Regulatory T Cells in Colon Cancer ERDMAN et al. Toxicologic Pathology, 38: 76-87, 2010 肠道菌群紊乱与疾病 北京大学人民医院 消化内科 朱元民 肠道细菌的建立及功能 肠道菌群 Gut Microbiota 人体结肠细菌细胞细胞数量高达100万亿,是人体细胞数量的10倍。 在分娩过程中细菌即植入新生儿肠道内。分娩方式、喂奶方式等影响新生儿的肠道菌群结构。 母乳喂养的婴儿粪便中双歧杆菌的比例增加，配方喂奶婴儿粪便中肠球菌比例增加。 Orrhage K, Nord CE. Factors controlling the bacterial colonization of the intestine in breast fed infants. Acta Paediatr. 1999;88(430):47S-57S Biasucci G, Rubini M, Riboni S, Retetangos C, Morelli L, Bessi E. Mode of delivery affects the bacterial community in the newborn gut. Early Hum Dev. 2010 Feb 4. 人体消化道细菌分布 人体结肠菌群结构 肠道菌群 Gut Microbiota Microbes act as a defending barrier against invading pathogens, aid in digestion, provide nutritional support for enterocytes, and play a crucial role in the development of the immune system. Specific pathogens (e.g., Salmonella, Campylobacter jejuni, and enterotoxigenic C. perfringens) have been implicated in acute and chronic gastrointestinal disease. 婴幼儿年龄阶段的环境因素对成年期肠道菌群结构及肠道免疫功能有重要影响。 肠道菌群紊