小檗碱对大鼠肠道菌群结构的体外影响

目的研究小檗碱在体外对高脂饮食诱导的肥胖、胰岛素抵抗大鼠(HFD)肠道菌群和正常饮食对照大鼠(NCD)肠道菌群结构的体外影响。方法采用体外厌氧培养、PCR-DGGE和454焦磷酸测序技术研究小檗碱对肠道菌群结构和多样性的影响。结果 DGGE指纹图谱和454焦磷酸测序结果都表明,小檗碱可以改变肠道菌群的结构,高剂量的小檗碱可以减少肠道微生物的多样性。应用偏最小二乘法判别模型分析(PLS-DA)挑选与小檗碱相关的细菌类群(OTU),在HFD组中挑选了55个关键OTUs,其中53个被明显抑制或消除,剩余2个分别属于Proteus和Escherichia/Shigella属的OTUs则被小檗碱富集。在NCD组中挑选的51个关键OTUs中,32个被小檗碱抑制,17个被小檗碱富集。被富集的除了属于Klebsielal属的OTU外,还包括可以产生短链脂肪酸的Lactobacillus、Blautia属的OTUs。结论小檗碱可以直接调节肠道菌群的结构,对不同结构的肠道菌群其作用也不相同,不同浓度的小檗碱对肠道菌群的影响有较大差异。高浓度的小檗碱可以抑制大部分细菌的生长(其中有很多为肠道条件致病菌),减少肠道微生物的多样性,富集Enterobacteriaceae科的细菌(Proteus、Escherichia/Shigella、Klebsielal)。相较于HFD组,小檗碱可以显著富集NCD组大鼠肠道菌群中的短链脂肪酸产生菌。     

基于性别二分类的青海天峻藏民肠道菌群差异分析

目的 对青海省天峻县的藏族牧民健康志愿者肠道菌群进行研究,探讨青海藏民肠道菌群结构及性别对肠道菌群组成的影响。方法 以28例藏族牧民志愿者的粪便样品作为研究对象,应用基于16S rDNA V3+V4可变区的高通量测序技术测定肠道菌群组成及核心菌群;通过db-RDA和菌群多样性分析,探索性别因素对肠道菌群结构的影响。结果 在门水平上,厚壁菌门和拟杆菌门是青海藏族志愿者的优势菌群。在属水平上,优势菌属是普氏菌属、Lachnospiracea_incertae_sedis、Faecalibacterium和拟杆菌属;特有优势菌属是Lachnospiracea_incertae_sedis。db-RDA结果显示性别因素对肠道微生物群结构有一定分离趋势,多样性结果进一步证实性别差异显著影响菌群结构。男性和女性存在12种差异菌群,包括普氏菌属、Acidaminobacter属等。结论 性别差异对青海藏民肠道菌群影响显著。     

氟化物对家蚕肠道微生物菌群的影响

摘要:【目的】探讨氟化物对家蚕肠道微生物菌群的影响,开发具有潜在应用价值的益生菌以提高家蚕对氟化物的抗性。【方法】PCR扩增家蚕肠道内细菌16S rRNA基因并构建克隆文库;用核糖体DNA限制性分析(Amplified ribosomal DNA restriction analysis,ARDRA)方法对克隆子进行分型。从家蚕T6和734肠道样品中共获得14种分类操作单元(Operational taxonomic unit,OTUs),以16S rRNA基因为基础构建系统发育树进行分析。再经巢式PCR-DGGE技术检测家蚕肠道内优势菌群的变化。【结果】结果表明:家蚕氟中毒后肠道内肠球菌属Enterococcus和芽孢杆菌属Bacillus细菌菌群减少,而葡萄球菌属Staphylococcus的细菌增多。【结论】氟化物能通过改变家蚕肠道内细菌的多样性和比例,从而破坏家蚕肠道微生物菌群平衡,且对家蚕734的影响作用大于T6。     

枯草杆菌二联活菌肠溶胶囊对 溃疡性结肠炎患者肠道菌群的影响

目的探讨枯草杆菌二联活菌肠溶胶囊对溃疡性结肠炎患者肠道菌群的影响。方法选取2017年4月至2017年9月同济大学附属第十人民医院消化内科门诊收治的10例溃疡性结肠炎患者为研究对象。患者均在美沙拉嗪治疗基础上加用枯草杆菌二联活菌肠溶胶囊治疗1个月,留取治疗前后新鲜粪便样本,并采用16SrRNA细菌检测技术鉴定肠道菌群。结果患者经过治疗后其肠道菌群的丰富度没有发生改变,菌群的多样性增高。在门水平上,厚壁菌门丰度增高,而变形菌门的丰度下降。在属水平上,Actinobacillus和Escherichia/Shigella的丰度下降,Veillonella、Clostridium XIVa、Blautia、Proteus、Flavonifractor等的丰度增高(P0.05)。通过Lefse分析发现c_Gammaproteobacteria和p_Firmicutes是患者治疗前后的特征性菌群。结论枯草杆菌二联活菌肠溶胶囊可以改善溃疡性结肠炎患者的肠道菌群失调,在常规治疗中添加益生菌可成为一种新的治疗策略。     

不同饲料饲养家蚕其肠道微生态优势菌群类型的组成及差异性

为探讨鳞翅目昆虫的生长发育及抗病性与肠道微生态状况的关系,以不同的桑科植物柘叶与桑叶分别饲养家蚕,采用纯培养分离检测技术、16S rDNA序列测定和系统发育分析方法,对4、5龄家蚕肠道优势菌群的类型进行了鉴定和差异性分析。结果表明:柘叶与桑叶饲养家蚕共有的优势菌群有短波单胞杆菌属(Brevundimonas)、寡养单胞菌属(Stenotrophomonas)、肠杆菌属(Enterobacter)和葡萄球菌属(Staphylococcus)4个类群。从桑叶饲养家蚕肠道中检索到的优势菌群还有气单胞菌属(Aeromonas)、短杆菌属(Brevibacterium)、柠檬酸杆菌属(Citrobacter)、埃希氏菌属(Escherichia)和克雷伯氏菌属(Klebsiella)5个类群,而从柘叶饲养家蚕肠道中检索到的优势菌群仅有假单胞菌属(Pseudomonas)和土壤杆菌属(Agrobacterium)2个类群。饲料的改变导致家蚕肠道微生态细菌种群组成的变化,从柘叶饲养家蚕肠道中分离出的优势菌群与桑叶饲养的家蚕相比,出现较大差异且不如桑叶饲养家蚕的菌群丰富。推测这种改变可能与柘叶饲养家蚕生长发育不良、容易患病具有相关性。     

宜春温泉水体与泉底沉积物细菌多样性分析

研究宜春富硒温泉水体与泉底沉积物的细菌群落多样性。利用高通量测序技术分析泉水与沉积物中细菌群落结构与多样性。温泉水中主要的细菌类群为变形菌门和拟杆菌门,而在沉积物样品中的主要优势菌群为OP1、蓝细菌、浮霉菌门和绿弯菌门。细菌在属分类水平上,温泉水中优势菌群为不动杆菌属、假单胞菌属、水栖菌属、Thermosynechococcus、鞘脂杆菌属和金黄杆菌属等。沉积物样品细菌中优势菌群属于未知物种,在数据库中并没有相关的注释信息;其中已知的优势菌属为Candidatus acetothermum、Thermosynechococcus、亚热栖菌属、不动杆菌属。宜春温汤富硒温泉水体与沉积物中存在着丰富的微生物群落且组成差异性很大,该研究为了解与发掘温泉微生物菌种资源具有重要价值。     

普氏蹄蝠胃肠道菌群的多样性

【目的】研究普氏蹄蝠(Hipposideros pratti)胃肠道菌群多样性及致病菌的种类。【方法】采用Mi Seq高通量测序技术,通过对16S r RNA基因V1-V2区基因进行测序,研究普氏蹄蝠胃肠道细菌的群落组成。应用MG-RAST V3.3.6分析和统计样品序列和操作分类单元(OTU)数目,分析胃肠道菌群物种丰度,并进行聚类分析。【结果】从普氏蹄蝠胃和肠道中分别获得144 998条和275 274条原始序列以及48 332条和91 758条有效序列,分属于894个和756个操作分类单元。胃中菌群丰度指数Chao指数(1 490)和ACE指数(2 221)分别低于肠道菌群的Chao指数(2 051)和ACE指数(3 556);Shannon多样性指数(2.405)低于肠道(2.407);Simpson多样性指数(0.168)高于肠道(0.151)。系统进化分析表明胃肠中的细菌主要分布在6个门,均以变形菌门(Proteobacteria)(胃中占56.4%,肠中占46.0%)和厚壁菌门(Firmicutes)(胃中占40.7%,肠中占49.2%)为优势菌门。胃肠道中丰度在0.1%以上的属有24个,胃中优势类群为乳球菌属(Lactococcus)和哈夫尼菌属(Hafnia),分别占整个菌群的26.1%和21.0%;肠道中优势类群为肠球菌属(Enterococcus)和沙门氏菌属(Salmonella),分别占整个菌群的15.2%和12.7%。普氏蹄蝠胃肠道中的优势菌群均为人类的致病菌或者条件致病菌。【结论】普氏蹄蝠携带有大量人类致病菌。因此,应注意防止向人类传播。     

维持性血液透析终末期肾病患者肠道优势菌群多样性变化研究

目的探讨维持性血液透析终末期肾病患者肠道优势菌群多样性及其与炎症因子的相关性。方法采集维持性血液透析的稳定终末期肾病患者和健康对照受试者的血液和粪便样本,采用荧光实时定量PCR(real-time quantitative PCR,QPCR)检测肠道优势菌群的变化情况,应用酶联免疫吸附技术(enzymelinked immunosorbent assay,ELISA)检测患者血液中的白介素1β(interleukin 1β,IL-1β)、白介素6(interleukin 6,IL-6)、肿瘤坏死因子α(tumor necrosis factor-α,TNF-α)和内毒素(lipoposaccharide,LPS)。结果维持性血液透析终末期肾病患者肠道菌群总菌量差异无统计学意义,但肠道内有益菌群如双歧杆菌属细菌、乳酸杆菌属细菌和粪杆菌属细菌显著降低,而肠道内有害菌如肠杆菌科细菌和肠球菌属细菌均显著升高(P0.05)。维持性血液透析终末期肾病患者血液中IL-6、TNF-α和LPS显著升高,均与双歧杆菌属细菌有显著负相关,与肠杆菌科细菌有显著正相关。肠道内乳酸杆菌属细菌和粪杆菌属细菌与IL-6呈显著负相关,肠球菌属细菌与其呈显著正相关。此外,乳杆菌属细菌与TNF-α呈显著负相关,肠球菌属细菌和LPS呈显著正相关。结论维持性血液透析终末期肾病患者肠道优势菌群多样性发生了显著变化,且与患者炎症因子有密切的相关性。     

基于高通量测序对呼伦贝尔陶顺阿尔山细菌群落多样性的研究

对内蒙古呼伦贝尔陶顺阿尔山水体与沉积物的细菌群落结构和多样性，进行16S rRNA基因(V3～V5区)高通量测序。运用Illumina MiSeq高通量测序平台，共获得594 226条优化序列。结果显示，水体中最主要的细菌类群为变形菌门(Proteobacteria),而沉积物样品中的主要优势类群为盐厌氧菌门(Haloanaerobium);细菌在属分类水平上，水体中优势菌群为嗜盐单胞菌属(Halomonas)、冷弯菌属(Psychroflexus)、盐厌氧菌属(Haloanaerobium);沉积物样品中优势菌群为盐厌氧菌属、盐单胞菌属、未分类菌(no-rank-f-unclassified),其中存在大量的未知物种。陶顺阿尔山水体与沉积物中存在着丰富的微生物群落，且差异性大，未知菌种居多。本研究首次阐明了陶顺阿尔山细菌群落的多样性，为今后开发和利用陶顺阿尔山的功能菌群提供参考。     

综合养殖池塘中三角帆蚌和鱼类肠道细菌的组成

采用 PCR-DGGE (PCR-denaturing gradient gel electrophoresis)方法研究了综合养殖池塘中三角帆蚌(Hyriopsis cumingii)、草鱼(Ctenopharyngodon idella)、鳊(Parabramis pekinensis)、银鲫(Carassius auratus gibelio)、青鱼(Mylopharyngodon piceus)和鳙(Aristichthys nobilis)的肠道细菌组成,并分析了水体中的浮游细菌对鱼、蚌肠道细菌的影响。研究结果表明,三角帆蚌和混养鱼类肠道细菌属于厚壁菌门(Firmicutes)、变形菌门(Proteobacteria)、放线菌门(Actinobacteria)、疣微菌门(Verrucomicrobia)、蓝细菌(Cyanobacteria)、梭杆菌门(Fusobacteria)。其中,三角帆蚌肠道优势菌群为不动杆菌属(Acinetobacter)、志贺氏菌属(Shigella)和分枝杆菌属(Mycobacterium),草鱼肠道优势菌群为梭菌属(Clostridium),鳊肠道优势菌群为梭菌属和假单胞菌属(Pseudomonas),银鲫肠道优势菌群为不动杆菌属和志贺氏菌属,青鱼肠道优势菌群为梭菌属和不动杆菌属,鳙肠道优势菌群为不动杆菌属和弧菌属(Vibrio)。三角帆蚌与银鲫肠道细菌谱带相似性较高,草鱼与鳊肠道细菌谱带相似性较高,表明鱼类肠道细菌组成特点与食性存在一定的关系。水体浮游细菌优势菌群为类芽孢杆菌属(Paenibacillus)。三角帆蚌及鱼类肠道细菌群落与水体浮游细菌群落组成相似性较低,表明水体浮游细菌对三角帆蚌和鱼类肠道细菌优势菌群的影响有限。     

Structural Shifts of Fecal Microbial Communities in Rats with Acute Rejection after Liver Transplantation

Bacterial translocation and the development of sepsis after orthotopic liver transplantation (OLT) may be promoted by immunological damage to the intestinal mucosa or by quantitative and qualitative changes in intestinal microbiota. This study monitored structural shifts of gut microbiota in rats with OLT using PCR-denaturing gradient gel electrophoresis (DGGE) and real-time quantitative PCR (RT-qPCR). RT-qPCR targets six major microorganisms (Domain Bacteria, Bacteroides, Bifidobacteria, Enterobacteriaceae, Lactobacillus and Clostridium leptum subgroup). Isograft, Allograft and Sham model were studied. Bacterial translocation to host organs and plasma endotoxin were determined. Alteration in gut microbiota was associated with the elevation of plasma endotoxin and a higher rate of bacterial translocation (BT) to liver in rats with acute rejection. Dynamic analysis of DGGE fingerprints showed that the gut microbiota structure of animals in the three groups was similar before the operation. But significant alterations in the composition of fecal microbiota in Allograft group were observed at 1 and 2 weeks after the OLT. The acute rejection was accompanied by the shifts of gut microbiota towards members of Bacteroides and Ruminococcus. Results from RT-qPCR indicated that Bacteroides significantly increased at 2 weeks after the OLT, whereas numbers of Bifidobacterium spp. decreased at 1 week and recovered at 2 weeks after the OLT. In summary, our data showed that rats with acute rejection after OLT exhibited significant structure shifts in the gut microbiota which dominant by overgrowth of Bacteroides and Ruminococcus, and these were associated with elevation of plasma endotoxin and higher rate of BT.     

Structural resilience of the gut microbiota in adult mice under high-fat dietary perturbations

Disruption of the gut microbiota by high-fat diet (HFD) has been implicated in the development of obesity. It remains to be elucidated whether the HFD-induced shifts occur at the phylum level or whether they can be attributed to specific phylotypes; additionally, it is unclear to what extent the changes are reversible under normal chow (NC) feeding. One group (diet-induced obesity, DIO) of adult C57BL/6J mice was fed a HFD for 12 weeks until significant obesity and insulin resistance were observed, and then these mice were switched to NC feeding for 10 weeks. Upon switching to NC feeding, the metabolic deteriorations observed during HFD consumption were significantly alleviated. The second group (control, CHO) remained healthy under continuous NC feeding. UniFrac analysis of bar-coded pyrosequencing data showed continued structural segregation of DIO from CHO on HFD. At 4 weeks after switching back to NC, the gut microbiota in the DIO group had already moved back to the CHO space, and continued to progress along the same age trajectory and completely converged with CHO after 10 weeks. Redundancy analysis identified 77 key phylotypes responding to the dietary perturbations. HFD-induced shifts of these phylotypes all reverted to CHO levels over time. Some of these phylotypes exhibited robust age-related changes despite the dramatic abundance variations in response to dietary alternations. These findings suggest that HFD-induced structural changes of the gut microbiota can be attributed to reversible elevation or diminution of specific phylotypes, indicating the significant structural resilience of the gut microbiota of adult mice to dietary perturbations.     

The Microbiota‐Inflammasome Hypothesis of Major Depression

We propose the “microbiota‐inflammasome” hypothesis of major depressive disorder (MDD, a mental illness affecting the way a person feels and thinks, characterized by long‐lasting feelings of sadness). We hypothesize that pathological shifts in gut microbiota composition (dysbiosis) caused by stress and gut conditions result in the upregulation of pro‐inflammatory pathways mediated by the Nod‐like receptors family pyrin domain containing 3 (NLRP3) inflammasome (an intracellular platform involved in the activation of inflammatory processes). This upregulation exacerbates depressive symptomatology and further compounds gut dysbiosis. In this review we describe MDD/chronic stress‐induced changes in: 1) NLRP3 inflammasome; 2) gut microbiota; and 3) metabolic pathways; and how inflammasome signaling may affect depressive‐like behavior and gut microbiota composition. The implication is that novel therapeutic strategies could emerge for MDD and co‐morbid conditions. A number of testable predictions surface from this microbiota‐gut‐inflammasome‐brain hypothesis of MDD, using approaches that modulate gut microbiota composition via inflammasome modulation, fecal microbiota transplantation, psychobiotics supplementation, or dietary change.     

Predominant role of host genetics in controlling the composition of gut microbiota

Background

The human gastrointestinal tract is inhabited by a very diverse symbiotic microbiota, the composition of which depends on host genetics and the environment. Several studies suggested that the host genetics may influence the composition of gut microbiota but no genes involved in host control were proposed. We investigated the effects of the wild type and mutated alleles of the gene, which encodes the protein called pyrin, one of the regulators of innate immunity, on the composition of gut commensal bacteria. Mutations in MEFV lead to the autoinflammatory disorder, familial Mediterranean fever (FMF, MIM249100), which is characterized by recurrent self-resolving attacks of fever and polyserositis, with no clinical signs of disease in remission.

Methodology/Principal Findings

A total of 19 FMF patients and eight healthy individuals were genotyped for mutations in the MEFV gene and gut bacterial diversity was assessed by sequencing 16S rRNA gene libraries and FISH analysis. These analyses demonstrated significant changes in bacterial community structure in FMF characterized by depletion of total numbers of bacteria, loss of diversity, and major shifts in bacterial populations within the Bacteroidetes, Firmicutes and Proteobacteria phyla in attack. In remission with no clinical signs of disease, bacterial diversity values were comparable with control but still, the bacterial composition was substantially deviant from the norm. Discriminant function analyses of gut bacterial diversity revealed highly specific, well-separated and distinct grouping, which depended on the allele carrier status of the host.

Conclusions/Significance

This is the first report that clearly establishes the link between the host genotype and the corresponding shifts in the gut microbiota (the latter confirmed by two independent techniques). It suggests that the host genetics is a key factor in host-microbe interaction determining a specific profile of commensal microbiota in the human gut.     

Structural segregation of gut microbiota between colorectal cancer patients and healthy volunteers

Despite a long-suspected role in the development of human colorectal cancer (CRC), the composition of gut microbiota in CRC patients has not been adequately described. In this study, fecal bacterial diversity in CRC patients (n=46) and healthy volunteers (n=56) were profiled by 454 pyrosequencing of the V3 region of the 16S ribosomal RNA gene. Both principal component analysis and UniFrac analysis showed structural segregation between the two populations. Forty-eight operational taxonomic units (OTUs) were identified by redundancy analysis as key variables significantly associated with the structural difference. One OTU closely related to Bacteroides fragilis was enriched in the gut microbiota of CRC patients, whereas three OTUs related to Bacteroides vulgatus and Bacteroides uniformis were enriched in that of healthy volunteers. A total of 11 OTUs belonging to the genera Enterococcus, Escherichia/Shigella, Klebsiella, Streptococcus and Peptostreptococcus were significantly more abundant in the gut microbiota of CRC patients, and 5 OTUs belonging to the genus Roseburia and other butyrate-producing bacteria of the family Lachnospiraceae were less abundant. Real-time quantitative PCR further validated the significant reduction of butyrate-producing bacteria in the gut microbiota of CRC patients by measuring the copy numbers of butyryl-coenzyme A CoA transferase genes (Mann–Whitney test, P<0.01). Reduction of butyrate producers and increase of opportunistic pathogens may constitute a major structural imbalance of gut microbiota in CRC patients.     

Gut bacteria profiles of Mus musculus at the phylum and family levels are influenced by saturation of dietary fatty acids

BackgroundMammalian gut microbiota have been implicated in a variety of functions including the breakdown of ingested nutrients, the regulation of energy intake and storage, the control of immune system development and activity, and the synthesis of novel chemicals. Previous studies have shown that feeding mammalian hosts a high-fat diet shifts gut bacteria at the phylum level to reduce the ratio of Bacteroidetes-to-Firmicutes, while feeding hosts a fat-restricted diet increases this ratio. However, few studies have investigated the differential effects of fatty acid type on gut bacterial profile.MethodsOver a 14-week period, Mus musculus were fed a diet rich in omega-3 polyunsaturated fatty acids (n-3 PUFAs), omega-6 polyunsaturated fatty acids (n-6 PUFAs), or saturated fatty acids (SFAs). Fecal pellets were collected before and after the treatment period from 12 randomly selected mice (4 per treatment group). Bacterial DNA was extracted from the pellets and characterized by analysis of the hypervariable V3 region of the 16S rRNA. Nominal logistic regression models were used to assess shifts in microbial profile at the phylum and family levels in response to diet.ResultsA significant decrease in the proportion of phylum Bacteroidetes species was observed for mice fed any of the three diets over time. However, the SFA-rich diet group showed a significantly greater decrease in Bacteroidetes proportion (?28%) than did either the n-3 PUFA group (?10%) or the n-6 PUFA group (?12%). At the family level, a significant decrease in proportion of Porphyromonadaceae was observed for mice fed the n-6 PUFA-rich diet, and a significant decrease in proportion of Lachnospiraceae was observed for mice fed the SFA-rich diet. There was no significant effect of diet type on body mass change.ConclusionOur results indicate that SFAs have stronger effects than PUFAs in shifting gut microbiota profiles toward those typical of obese individuals, and that dietary fatty acid saturation influences shifts in gut microbiota independently of changes in body mass.     

Gut microbiota in patients after surgical treatment for colorectal cancer

Colorectal cancer (CRC) is a common disease worldwide that is strongly associated with the gut microbiota. However, little is known regarding the gut microbiota after surgical treatment. 16S rRNA gene sequencing was used to evaluate differences in gut microbiota among colorectal adenoma patients, CRC patients, CRC postoperative patients and healthy controls by comparing gut microbiota diversity, overall composition and taxonomic signature abundance. The gut microbiota of CRC patients, adenoma patients and healthy controls developed in accordance with the adenoma-carcinoma sequence, with impressive shifts in the gut microbiota before or during the development of CRC. The gut microbiota of postoperative patients and CRC patients differed significantly. Subdividing CRC postoperative patients according to the presence or absence of newly developed adenoma which based on the colonoscopy findings revealed that the gut microbiota of newly developed adenoma patients differed significantly from that of clean intestine patients and was more similar to the gut microbiota of carcinoma patients than to the gut microbiota of healthy controls. The alterations of the gut microbiota between the two groups of postoperative patients corresponded to CRC prognosis. More importantly, we used the different gut microbiota as biomarkers to distinguish postoperative patients with or without newly developed adenoma, achieving an AUC value of 0.72. These insights on the changes in the gut microbiota of CRC patients after surgical treatment may allow the use of the microbiota as non-invasive biomarkers for the diagnosis of newly developed adenomas and to help prevent cancer recurrence in postoperative patients.     

Modulation of gut microbiota contributes to curcumin-mediated attenuation of hepatic steatosis in rats

BackgroundStructural disruption of gut microbiota contributes to the development of non-alcoholic fatty liver disease (NAFLD) and modulating the gut microbiota represents a novel strategy for NAFLD prevention. Although previous studies have demonstrated that curcumin alleviates hepatic steatosis, its effect on the gut microbiota modulation has not been investigated.MethodsNext generation sequencing and multivariate analysis were utilized to evaluate the structural changes of gut microbiota in a NAFLD rat model induced by high fat-diet (HFD) feeding.ResultsWe found that curcumin attenuated hepatic ectopic fat deposition, improved intestinal barrier integrity, and alleviated metabolic endotoxemia in HFD-fed rats. More importantly, curcumin dramatically shifted the overall structure of the HFD-disrupted gut microbiota toward that of lean rats fed a normal diet and altered the gut microbial composition. The abundances of 110 operational taxonomic units (OTUs) were altered by curcumin. Seventy-six altered OTUs were significantly correlated with one or more hepatic steatosis associated parameters and designated ‘functionally relevant phylotypes’. Thirty-six of the 47 functionally relevant OTUs that were positively correlated with hepatic steatosis associated parameters were reduced by curcumin.ConclusionThese results indicate that curcumin alleviates hepatic steatosis in part through stain-specific impacts on hepatic steatosis associated phylotypes of gut microbiota in rats.General significanceCompounds with antimicrobial activities should be further investigated as novel adjunctive therapies for NAFLD.     

胆管结扎对大鼠肠道双歧杆菌组成的影响

目的分析胆管结扎对SD大鼠肠道双歧杆菌菌群结构组成的影响。方法采集手术前3 d和手术后2周5只模型组和5只对照组大鼠的粪便样品,提取粪便样品中微生物的混合DNA进行双歧杆菌类群特异性PCR-DGGE,结合主成分分析技术比较2组大鼠在手术前后肠道内双歧杆菌结构组成的变化。结果DGGE图谱及其主成分分析表明手术后对照组和模型组大鼠肠道双歧杆菌菌群的结构组成明显不同,主要表现在假长双歧杆菌的数量在模型组显著增加,而动物双歧杆菌却明显减少。结论胆管结扎导致SD大鼠肠道双歧杆菌结构发生异常变化。