摘要
目的了解克罗恩病患者同健康人群肠道黏膜相关细菌群落多样性差异。方法选择2010年9月至2011年12月在华西医院确诊的克罗恩病患者8例（克罗恩病组）和23名健康体检者（健康对照组），分别于结肠镜检查时取盲肠黏膜组织1块。末端限制性片段长度多态性（T—RFLP）检测黏膜相关细菌多样性；聚类分析法比较菌群组成差异，比较两组菌群多样性及优势菌群组成差异，通过MiCA数据库寻找优势末端片段可能代表的细菌种类。结果聚类分析显示克罗恩病组与健康对照组黏膜相关细菌组成不同，各组内样本相似性明显高于组问样本。克罗恩病组细菌丰度Haem酶切和MspI＋HaeHI酶切显著峰数量（操作分类单元）均低于健康对照组[Haem：（7±4）比（10±8）个、P=0．048，MspI＋Haem：（20±10）比（24±12）个、P=0．036]。克罗恩病组Shannon—Wiener指数与健康对照组差异无统计学意义（1．7±0．7比2．0±0．5，P=0．220）；克罗恩病组物种均匀度和Simpson指数均高于健康对照组（0．84±0．14比0．77±0．13、0．25±0．16比0．22±0．15，P=0．045、0．038）。在MspI酶切分析中，37、40、66bp为克罗恩病组特有优势末端片段；相对定量比较提示克罗恩病组35bp含量高于健康对照组[36．8％（23．O％，55．4％）比14．3％（9．5％，19．5％），P=0．001]；74、141、486、490bp含量则均低于健康对照组[3．2％（1．3％，5．1％）比10．2％（5．4％，17．3％），4．5％（1．7％，7．1％）比10．8％（5．9％，21．1％），4．2％（1．6％，5．3％）比7．6％（5．9％，9．3％），3．6％（2．4％，6．1％）比18．3％（9．9％，43．2％），P=0．001、0．007、0．022、0．008]。克罗恩病组黏膜相关细菌以硬壁菌门、变形菌门、放线菌门为主；与健康对照组比较，克罗恩病患者中拟杆菌明显少，硬壁菌门中的肠杆菌属及放线菌属含量明显多。结论克罗恩病患者存在明显肠道菌群失调，黏膜相关细菌丰度及多样性减少，拟杆菌的减少和硬壁菌门中的肠杆菌属、放线菌属含量增加可能在克罗恩病的发生及发展中扮演重要作用。
[ Abstract] Objective To explore the differences of colonic mucosal-associate bacterial diversity between the patients with Crohn＇s disease （CD） and healthy controls. Methods Eight CD patients and 23 healthy controls were recruited from September 2010 to December 2011 at West China Hospital. One biopsy were taken from cecum of every patient with CD and healthy control by endoscopic examination. The diversity of colonic mueosa-associated mierobiota was detected by terminal-restriction fragment length polymorphism （T-RFLP） . Hierarchical cluster analysis were performed to compare the similarity of microbial communities between CD patients and healthy controls. Differences of bacterial diversity between two groups were also evaluated. The difference of predominant terminal-restrict fragments （T-RF） were analyzed and the bacterium predicted by predominant T-RFs were identified according to MiCA database. Results Hierarchical cluster analysis showed that the mueosal microbial community of CD patients differed from healthy controls. And there were more similarities in the samples of same group than that of different groups. Compared with healthy control group, the richness of mocosal microbiota in CD patients was lower （ Hae III： 7 ± 4 vs 10± 8, P = 0. 048 ; Msp I ± HaeIII ：20 ± 10 vs 24± 12, P =0. 036）. Shannon-Wiener index of CD patients was lower than healthy control（ 1.7 ± 0. 7 vs 2. 0 ＋ 0. 5, P = 0. 220） with no significant difference.Species evenness and Simpson index of CD patients were significantly greater than healthy controls （0. 84 ±0.14vs0.77±0.13, P = 0. 045 ; 0. 25 ±0.16 vs 0. 22 ±0.15 , P=0.038）. The T-RF of 37, 40 and 66 bp digested with Msp I enzyme predominated in CD patients. Relative quantitative analysis showed 35 bp T- RF digested with Msp I was significantly higher in CD patients than that in healthy controls （36. 8% （23.0% , 55.4% ） vs 14. 3% （9.5% , 19.5% ） , P =0. 001） , and 74, 141,486,490 bp T-RFs were all significantly lower than healthy controls （3.2% （ 1.3 %, 5.1% ） vs 10. 2% （5.4%, 17.3 % ）, P =0. 001 ; 4.5% （1.7%, 7. 1%） vs 10.8% （5.9%, 21.1%）, P =0.007; 4.2% （1.6%, 5.3%） vs 7.6% （5.9%, 9.3%）, P=0.022; 3.6%（2.4%, 6. 1%） vs 18.3% （9.9%, 43.2%）, P=0.008）. The mucosal bacterial community composition in CD patients was predominated by Firmicutes, Proteobacterium and Actinobacterium. Compare with healthy control, Bacteroides were significantly reduced in CD patients while Firmicutes （e.g. Enterobacter sp. ） and Actinomycetaceae significantly increased. Conclusions Dysbiosis of mucosal microbiota occurs in CD with decreases of richness and biodiversity. Increased Enterobacter sp. , Actinobacterium and decreased Bacteroides may play an important role in the pathogenesis of CD.
出处
《中华医学杂志》
CAS
CSCD
北大核心
2013年第36期2884-2889,共6页
National Medical Journal of China
作者简介
冉文斌（现在成都市第三人民医院消化内科）
通信作者：欧阳钦，Email：qin．ouyang@163．com
