Human gut microbiota in obesity and after gastric bypass
Human gut microbiota in obesity and after gastric bypass
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DOI：
10.1073/pnas.0812600106
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发表时间：
2009-02-17
影响因子：
11.1
通讯作者：
Krajmalnik-Brown, Rosa
中科院分区：
文献类型：
--
作者：
Zhang, Husen;DiBaise, John K.;Krajmalnik-Brown, Rosa
最近的证据表明，人体肠道中的微生物群落可能在肥胖的发病机制中起重要作用。我们通过使用454焦磷酸测序技术从PCR扩增子中检测了184，094个微生物16 S rRNA基因序列，以比较9个个体的微生物群落结构，正常体重、病态肥胖和胃旁路手术后各3个。系统发育分析表明，虽然人类肠道菌群中的细菌高度多样性，但它们主要分为6个细菌分支，在3个研究组中存在明显差异。具体来说，硬壁菌门在正常体重和肥胖个体中占主导地位，但在胃旁路手术后个体中显着减少，这些个体的γ-变形菌门数量呈比例增加。产生H-2的普雷沃氏菌科的数量在肥胖个体中高度富集。与高度多样性的细菌不同，该菌主要由甲烷菌目（Methanobacteriales）的成员组成，这是一种H-2氧化产甲烷菌。使用实时PCR，我们检测到显着更高的H-2利用产甲烷菌在肥胖的个人比正常体重或胃旁路手术后的个人。在肥胖个体的胃肠道中，产生H-2的细菌与相对高数量的利用H-2的产甲烷菌的共存导致了以下假设：细菌和古细菌物种之间的种间H-2转移是肥胖者中人类大肠增加能量摄取的重要机制。在胃旁路术后个体中观察到的大的细菌群体变化可能反映了由外科手术引起的肠道改变以及随之而来的食物摄取和消化变化的双重影响。
Recent evidence suggests that the microbial community in the human intestine may play an important role in the pathogenesis of obesity. We examined 184,094 sequences of microbial 16S rRNA genes from PCR amplicons by using the 454 pyrosequencing technology to compare the microbial community structures of 9 individuals, 3 in each of the categories of normal weight, morbidly obese, and post-gastric-bypass surgery. Phylogenetic analysis demonstrated that although the Bacteria in the human intestinal community were highly diverse, they fell mainly into 6 bacterial divisions that had distinct differences in the 3 study groups. Specifically, Firmicutes were dominant in normal-weight and obese individuals but significantly decreased in post-gastric-bypass individuals, who had a proportional increase of Gammaproteobacteria. Numbers of the H-2-producing Prevotellaceae were highly enriched in the obese individuals. Unlike the highly diverse Bacteria, the Archaea comprised mainly members of the order Methanobacteriales, which are H-2-oxidizing methanogens. Using real-time PCR, we detected significantly higher numbers of H-2-utilizing methanogenic Archaea in obese individuals than in normal-weight or post-gastric-bypass individuals. The coexistence of H-2-producing bacteria with relatively high numbers of H-2-utilizing methanogenic Archaea in the gastrointestinal tract of obese individuals leads to the hypothesis that interspecies H-2 transfer between bacterial and archaeal species is an important mechanism for increasing energy uptake by the human large intestine in obese persons. The large bacterial population shift seen in the post-gastric-bypass individuals may reflect the double impact of the gut alteration caused by the surgical procedure and the consequent changes in food ingestion and digestion.