Effects of early postnatal gastric and colonic microbiota transplantation on piglet gut health

Background Diarrhea is a major cause of reduced growth and mortality in piglets during the suckling and weaning periods and poses a major threat to the global pig industry.Diarrhea and gut dysbiosis may in part be prevented via improved early postnatal microbial colonization of the gut.To secure better postnatal gut colonization,we hypothesized that transplantation of colonic or gastric content from healthy donors to newborn recipients would prevent diarrhea in the recipients in the post-weaning period.Our objective was to examine the impact of transplanting colonic or gastric content on health and growth parameters and paraclinical parameters in recipient single-housed piglets exposed to a weaning transition and challenged with enterotoxigenic Escherichia coli(ETEC).Methods Seventy-two 1-day-old piglets were randomized to four groups:colonic microbiota transplantation(CMT,n=18),colonic content filtrate transplantation(CcFT,n=18),gastric microbiota transplantation(GMT,n=18),or saline(CON,n=18).Inoculations were given on d 2 and 3 of life,and all piglets were milk-fed until weaning(d 20)and shortly after challenged with ETEC(d 24).We assessed growth,diarrhea prevalence,ETEC concentration,organ weight,blood parameters,small intestinal morphology and histology,gut mucosal function,and microbiota composition and diversity.Results Episodes of diarrhea were seen in all groups during both the milk-and the solid-feeding phase,possibly due to stress associated with single housing.However,CcFT showed lower diarrhea prevalence on d 27,28,and 29 compared to CON(all P<0.05).CcFT also showed a lower ETEC prevalence on d 27(P<0.05).CMT showed a higher alpha diversity and a difference in beta diversity compared to CON(P<0.05).Growth and other paraclinical endpoints were similar across groups.Conclusion In conclusion,only CcFT reduced ETEC-related post-weaning diarrhea.However,the protective effect was marginal,suggesting that higher doses,more effective modalities of administration,longer treatment periods,and better donor quality should be explored by future research to optimize the protective effects of transplantation.

Dietary proline supplementation alters colonic luminal microbiota and bacterial metabolite composition between days 45 and 70 of pregnancy in Huanjiang mini-pigs

Background: Pregnancy is associated with important changes in gut microbiota composition. Dietary factors may affect the diversity, composition, and metabolic activity of the intestinal microbiota. Among amino acids, proline is known to play important roles in protein metabolism and structure, cell differentiation, conceptus growth and development, and gut microbiota re-equilibration in case of dysbiosis.Results: Dietary supplementation with 1% proline decreased(P < 0.05) the amounts of Klebsiella pneumoniae,Peptostreptococcus productus, Pseudomonas, and Veillonella spp. in distal colonic contents than that in the control group. The colonic contents of Butyrivibrio fibrisolvens, Bifidobacterium sp., Clostridium coccoides, Clostridium coccoides-Eubacterium rectale, Clostridium leptum subgroup, Escherichia coli, Faecalibacterium prausnitzii,Fusobacterium prausnitzii, and Prevotella increased(P < 0.05) on d 70 of pregnancy as compared with those on d 45 of pregnancy. The colonic concentrations of acetate, total straight-chain fatty acid, and total short-chain fatty acids(SCFA) in the proline-supplemented group were lower(P < 0.05), and butyrate level(P = 0.06) decreased as compared with the control group. Almost all of the SCFA displayed higher(P < 0.05) concentrations in proximal colonic contents on d 70 of pregnancy than those on d 45 of pregnancy. The concentrations of 1,7-heptyl diamine(P = 0.09) and phenylethylamine(P < 0.05) in proximal colonic contents were higher, while those of spermidine(P = 0.05) and total bioamine(P = 0.06) tended to be lower in the proline-supplemented group than those in the control group. The concentrations of spermidine, spermine, and total bioamine in colonic contents were higher(P < 0.05) on d 70 of pregnancy than those measured on d 45 of pregnancy. In contrast, the concentration of phenylethylamine was lower(P < 0.05) on d 70 than on d 45 of pregnancy.(Continued on next page)(Continued from previous page)Conclusion: These findings indicate that L-proline supplementation modifies both the colonic microbiota composition and the luminal concentrations of several bacterial metabolites. Furthermore, our data show that both the microbiota composition and the concentrations of bacterial metabolites are evolving in the course of pregnancy. These results are discussed in terms of possible implication in terms of luminal environment and consequences for gut physiology and health.

Low-protein diets supplemented with casein hydrolysate favor the microbiota and enhance the mucosal humoral immunity in the colon of pigs

Background:High-protein diets can increase the colonic health risks.A moderate reduction of dietary crude-protein(CP)level can improve the colonic bacterial community and mucosal immunity of pigs.However,greatly reducing the dietary CP level,even supplemented with all amino acids(AAs),detrimentally affects the colonic health,which may be due to the lack of protein-derived peptides.Therefore,this study evaluated the effects of supplementation of casein hydrolysate(peptide source)in low-protein(LP)diets,in comparison with AAs supplementation,on the colonic microbiota,microbial metabolites and mucosal immunity in pigs,aiming to determine whether a supplementation of casein hydrolysate can improve colonic health under very LP level.Twenty-one pigs(initial BW 19.90±1.00 kg,63±1 days of age)were assigned to three groups and fed with control diet(16%CP),LP diets(13%CP)supplemented with free AAs(LPA)or casein hydrolysate(LPC)for 4 weeks.Results:Compared with control diet,LPA and LPC diet decreased the relative abundance of Streptococcus and Escherichia coli,and LPC diet further decreased the relative abundance of Proteobacteria.LPC diet also increased the relative abundance of Lactobacillus reuteri.Both LP diets decreased concentrations of ammonia and cadaverine,and LPC diet also reduced concentrations of putrescine,phenol and indole.Moreover,LPC diet increased total short-chain fatty acid concentration.In comparison with control diet,both LP diets decreased protein expressions of Toll-like receptor-4,nuclear factor-κB,interleukin-1βand tumor necrosis factor-α,and LPC diet further decreased protein expressions of nucleotide-binding oligomerization domain protein-1 and interferon-γ.LPC diet also increased protein expressions of G-protein coupled receptor-43,interleukin-4,transforming growth factor-β,immunoglobulin A and mucin-4,which are indicators for mucosal defense activity.Conclusions:The results showed that supplementing casein hydrolysate showed beneficial effects on the colonic microbiota and mucosal immunity and barrier function in comparison with supplementing free AAs in LP diets.These findings may provide new framework for future nutritional interventions for colon health in pigs.

Mechanisms linking dietary fiber, gut microbiota and colon cancer prevention

Many epidemiological and experimental studies have suggested that dietary fiber plays an important role in colon cancer prevention. These findings may relate to the ability of fiber to reduce the contact time of carcinogens within the intestinal lumen and to promote healthy gut microbiota, which modifies the host's metabolism in various ways. Elucidation of the mechanisms by which dietary fiber-dependent changes in gut microbiota enhance bile acid deconjugation, produce short chain fatty acids, and modulate inflammatory bioactive substances can lead to a better understanding of the beneficial role of dietary fiber. This article reviews the current knowledge concerning the mechanisms via which dietary fiber protects against colon cancer.

SCFA Profile of Rice RS Fermentation by Colonic Microbiota, <i>Clostridium butyricum</i>BCC B2571, and <i>Eubacterium rectale</i>DSM 17629

Resistant starch type 3 (RS3) produced from high amylose food sources through retrogradation or enzymatic process is known to have physiological function as dietary fiber. Fermentation of RS3 by colonic microorganisms produced SCFA (acetate, propionate, and butyrate), maintained the health of colon, balance of gut microbiota, preventing inflammatory bowel diseases (IBD) and colon cancer. RS3 in this study was produced from IR-42 and Inpari-16 broken rice by enzymatic treatment (combination of amylase-pullulanase). The Resistant Starch was fermented for 12 and 24 h by colonic microbiota (extracted from healthy human subject), Clostiridium butyricum BCC-B2571, or Eubacterium rectale DSM 17629. SCFA produced was analyzed by gas chromatography. Treatment by amylase-pullulanase combination was advantageous to increase their RS3 content. The result showed that after enzymatic process, the RS3 content of IR-42 (41.13%) was not significantly different (p 0.05) from that of Inpari-16 (37.70%). High concentration of acetate (82.5 mM) and propionate (7.5 mM) were produced by colonic microbiota after 12 h fermentation and best concentration of butyrate (6.8 mM) was produced by colonic microbiota after 24 h fermentation. It is clear that utilization of colonic microbiota rather than single strain was better in the production of SCFA.

Hermetia illucens larvae as a potential dietary protein source altered the microbiota and modulated mucosal immune status in the colon of finishing pigs

Background: Insects, such as Hermetia illucens larvae, are rich in chitin and proteins, and represent a suitable feed ingredient replacement for animals. However, little is known about the effect of administering H. illucens larvae on intestinal microbiota, bacterial metabolite profiles, and mucosal immune status in animals. This study aimed to investigate the effects of administering H. illucens larvae on colonic microbiota and bacterial metabolites production in finishing pigs. Seventy-two crossbred(Duroc × Landrace × Large White) female pigs(initial body weight, 76.0 ± 0.52 kg) were randomly allocated to three different dietary treatments: a control diet(Control group) and two diets corresponding to 4%(H1 group) and 8%(H2 group) H. illucens larvae inclusion levels, respectively. Each treatment consisted of eight pens(replicates), with three pigs per pen. After 46 days of feeding, eight pigs per treatment(n =8) were slaughtered, and the colonic digesta and mucosa were collected for microbial composition and microbial fermentation products, and genes expression analyses.Results: The results showed that the H1 diet significantly increased the abundance of Lactobacillus,Pseudobutyrivibrio, Roseburia, and Faecalibacterium compared with those in the control group(P < 0.05), with a decrease in the abundance of Streptococcus. The numbers of Lactobacillus, Roseburia, and Clostridium cluster XIVa were significantly greater in the H1 group than in the control group(P < 0.05). Meanwhile, H2 diet increased the number of Clostridium cluster XIVa compared with the control group(P < 0.05). For colonic metabolites, total short chain fatty acids, butyrate, and isobutyrate concentrations were significantly higher in the H1 group than those in the control group(P < 0.05);the H1 treatment caused a striking decrease in protein fermentation compared with the control group, as the concentrations of total amines, cadaverine, tryptamine, phenol, p-cresol, and skatole were significantly lower(P < 0.05). Additionally, H2 diet also increased butyrate concentration compared with control group(P < 0.05), while decreased the concentrations of phenol, p-cresol, and skatole(P < 0.05). Pigs in the H1 group down-regulated the expression of TLR-4 and pro-inflammatory cytokines(IFN-γ) compared with pigs in the control group(P < 0.05), and up-regulated anti-inflammatory cytokine(IL-10) and intestinal barrier genes(ZO-1, occludin, and mucin-1). H2 diet up-regulated the expression of ZO-1 compared with control group(P < 0.05). Furthermore, the changes in the colonic mucosal gene expression were associated with changes in the bacterial composition and their metabolites.Conclusions: Collectively, dietary inclusion of Hermetia illucens larvae may enhance mucosal immune homeostasis of pigs via altering bacterial composition and their metabolites. These findings provide a new perspective on insect meal as a sustainable protein source rich in nutrient ingredients for swine.

Perioperative changes in lower gut microbiocenosis in patients with colon and rectum cancer

This clinical study was designed to determinate the value of colon microbiota microflora in colorectal cancer patients.We investigate pre-and post-operation stool samples in patients with different tumor localizations,trying to correlate those to postoperative complications.Our findings shows that if opportunistic pathogenic microflora levels are elevated before operations,it can lead to further microbiota disbalance in postoperative period,especially in cases of antibacterial prophylaxis or treatment.Further,this changes increase a chance of receiving some complications after surgery.So,we suggest an analysis of stool microbiota in patients with colorectal cancer to be performed prior and after the operation.Furthermore,aperioperative decontamination therapy should be performed in cases of pathogenic microflora levels elevation.Still,monitoring aperioperative microbiota changes is not a routine in most recommendations and we assume that including this relatively unencumbered patient testing in preoperative survey will help to reduce a number of postoperative complications.

Caecal pH is a biomarker of excessive colonic fermentation

AIM: To ascertain whether caecal pH is different in patients with irritable bowel syndrome (IBS), whose primary symptoms are bloating and distension, to healthy controls.

Impact of humic acids on the colonic microbiome in healthy volunteers

AIMTo test the effects of humic acids on innate microbial communities of the colon.METHODSWe followed the effects of oral supplementation with humic acids (Activomin®) on concentrations and composition of colonic microbiome in 14 healthy volunteers for 45 d. 3 × 800 mg Activomin® were taken orally for 10 d followed by 3 × 400 mg for 35 d. Colonic microbiota were investigated using multicolor fluorescence in situ hybridization (FISH) of Carnoy fixated and paraffin embedded stool cylinders. Two stool samples were collected a week prior to therapy and one stool sample on days 10, 31 and 45. Forty-one FISH probes representing different bacterial groups were used.RESULTSThe sum concentration of colonic microbiota increased from 20% at day 10 to 30% by day 31 and remained stable until day 45 (32%) of humic acid supplementation (P < 0.001). The increase in the concentrations in each person was due to growth of preexisting groups. The individual microbial profile of the patients remained unchanged. Similarly, the bacterial diversity remained stable. Concentrations of 24 of the 35 substantial groups increased from 20% to 96%. Two bacterial groups detected with Bac303 (Bacteroides) and Myc657 (mycolic acid-containing Actinomycetes) FISH probes decreased (P > 0.05). The others remained unaffected. Bacterial groups with initially marginal concentrations (< 0.1 × 109/mL) demonstrated no response to humic acids. The concentrations of pioneer groups of Bifidobacteriaceae, Enterobacteriaceae and Clostridium difficile increased but the observed differences were statistically not significant.CONCLUSIONHumic acids have a profound effect on healthy colonic microbiome and may be potentially interesting substances for the development of drugs that control the innate colonic microbiome.

Bacterial colonization and intestinal mucosal barrier development

The intestinal tract is colonized soon after birth with a variety of ingested environmental and maternal microflora. This process is influenced by many factors including mode of delivery, diet, environment, and the use of antibiotics. Normal intestinal microflora provides protection against infection, ensures tolerance to foods, and contributes to nutrient digestion and energy harvest. In addition, enteral feeding and colonization with the normal commensal flora are necessary for the maintenance of intestinal barrier function and play a vital role in the regulation of intestinal barrier function. Intestinal commensal microorganisms also provide signals that foster normal immune system development and influence the ensuing immune responses. There is increasingly recognition that alterations of the microbial gut flora and associated changes in intestinal barrier function may be related to certain diseases of the gastrointestinal tract. This review summarizes recent advances in understanding the complex ecosystem of intestinal microbiota and its role in regulating intestinal barrier function and a few common pediatric diseases. Disruption in the establishment of a stable normal gut microflora may contribute to the pathogenesis of diseases including inflammatory bowel disease, nosocomial infection, and neonatal necrotizing enterocolitis.

Impact of an oligosaccharide-based polymer on the metabolic profiles and microbial ecology of weanling pigs experimentally infected with a pathogenic E.coli

Background Our previous study has reported that supplementation of oligosaccharide-based polymer enhances gut health and disease resistance of pigs infected with enterotoxigenic E.coli(ETEC)F18 in a manner similar to carbadox.The objective of this study was to investigate the impacts of oligosaccharide-based polymer or antibiotic on the host metabolic profiles and colon microbiota of weaned pigs experimentally infected with ETEC F18.Results Multivariate analysis highlighted the differences in the metabolic profiles of serum and colon digesta which were predominantly found between pigs supplemented with oligosaccharide-based polymer and antibiotic.The relative abundance of metabolic markers of immune responses and nutrient metabolisms,such as amino acids and carbohydrates,were significantly differentiated between the oligosaccharide-based polymer and antibiotic groups(q<0.2 and fold change>2.0).In addition,pigs in antibiotic had a reduced(P<0.05)relative abundance of Lachnospiraceae and Lactobacillaceae,whereas had greater(P<0.05)Clostridiaceae and Streptococcaceae in the colon digesta on d 11 post-inoculation(PI)compared with d 5 PI.Conclusions The impact of oligosaccharide-based polymer on the metabolic and microbial profiles of pigs is not fully understood,and further exploration is needed.However,current research suggest that various mechanisms are involved in the enhanced disease resistance and performance in ETEC-challenged pigs by supplementing this polymer.

苹果幼果果粉对体外模拟人体结肠微生物群的影响

以苹果幼果为原料,采用真空冷冻干燥技术制备苹果幼果果粉(YAP),测定多酚和膳食纤维等主要成分含量,通过三阶段连续发酵系统模拟结肠发酵,并结合16S rRNA高通量测序和G C-MS分析,探究苹果幼果果粉对健康和肥胖志愿者结肠微生物群组成及短链脂肪酸的影响。结果表明,YAP中含有丰富的膳食纤维[(417.50±0.40)mg/g]和多酚类物质[(57.10±0.03)mg/g]。YAP使健康和肥胖志愿者的结肠反应器中菌群组成发生变化,其中Alpha多样性没有显著变化,而Beta多样性存在显著变化。低剂量YAP对结肠中不同细菌群的相对丰度有显著影响。在健康组中,YAP显著增加了拟杆菌门(Bacteroidota)的相对丰度,降低了变形菌门(Proteobacteria)的相对丰度;在肥胖组中,YAP显著增加了放线菌门(Actinobacteriota)的相对丰度。YAP对2个实验组属水平结肠微生物均有调节作用,使其相对丰度在7 d发酵周期内达到稳定值。此外,YAP促进了产短链脂肪酸菌的生成,增加了健康和肥胖志愿者结肠中的总短链脂肪酸浓度,短链脂肪酸中乙酸浓度最高。低剂量YAP显著增加了结肠样本中戊酸、丁酸和己酸的浓度(P<0.05)。体外模拟结肠发酵的结果表明,富含多酚和膳食纤维的YAP可显著调节健康和肥胖志愿者的结肠微生物群组成和短链脂肪酸含量,研究旨在为肠道菌群饮食调控提供新的思路和理论依据。

不同修饰型叶黄素纳米脂质体结肠消化过程稳定性及对粪便菌群调节作用

目的:在构建叶黄素脂质体(Lutein nanostructured lipid carriers,LNLs)的基础上,利用壳聚糖(chitosan,CS)、壳聚糖-表没食子儿茶素没食子酸酯共价(Chitosan epigallocatechin gallate covalent,C-CSEGCG)/非共价复合物(Chitosan epigallocatechin gallate ester non covalent,Non-C-CS-EGCG),结合高压微射流技术,制备不同修饰类型的叶黄素纳米脂质体。方法:通过建立模拟结肠消化模型,探明三种不同修饰类型叶黄素纳米脂质体在结肠消化过程中的稳定性以及与肠道菌群相互作用关系。结果表明:经24 h模拟体外结肠发酵后,CS-LNLs中叶黄素含量较其他处理组显著(P<0.05)降低;除叶黄素(Lutein,LUT)以及CS-LNLs外,其他处理组发酵后发酵液中总糖含量均显著下降(P<0.05),C-CS-EGCG-LNLs和Non-C-CS-EGCG-LNLs中总多酚含量变化呈现相反趋势;经24 h发酵后,除LUT组外,各处理组中乙酸和丙酸的产生量均显著增加(P<0.05),C-CS-EGCG-LNLs组乙酸浓度达到17.18±0.60 mmol/L;乳酸浓度达到2.87±0.05 mmol/L,显著(P<0.05)高于空白组(Blank Control Group,BLK)7.55倍;三种不同修饰类型叶黄素纳米脂质体对肠道菌群结构均产生显著影响,其中,CS-LNLs、C-CS-EGCG-LNLs和Non-C-CS-EGCG-LNLs中拟杆菌属、小杆菌属以及粪杆菌属相对丰度显著增加(P<0.05),而C-CS-EGCG-LNLs中富集了较多的韦永氏球菌属(Veillonella)。结论:在结肠消化阶段,与其他修饰组纳米脂质体相比,C-CS-EGCG-LNLs具有显著的肠道微生物结构差异性。

羔羊胃肠道微生物定植及影响因素

羔羊易发生肠道炎症,主要是因为其胃肠道(gastrointestinal tract,GIT)微生物发育尚不成熟,缺乏抵御病原菌的共生菌群。羔羊GIT微生物群的演替与其对营养物质的吸收及免疫系统的发育密切相关,靶向重建GIT微生物群具有抵抗肠道炎症发生的潜力。早期生命阶段是GIT微生物群建立和发育的关键时期,对动物后期生长性能和免疫系统的发育具有长远影响。因此,深入了解羔羊GIT微生物群的定植规律及影响因素,可为羔羊GIT疾病的预防提供理论依据。文章对羔羊GIT微生物群的定植过程、功能及定植的影响因素进行综述,阐述了羔羊GIT微生物群与营养物质吸收及免疫系统发育之间的相互关系,为羔羊GIT微生物群的相关研究提供参考。

结肠癌病人血清miR-448和miR-153表达对肠道菌群及免疫功能的影响

目的探讨结肠癌病人血清微小RNA-448(miR-448)和微小RNA-153(miR-153)表达对肠道菌群及免疫功能的影响。方法2020年2月~2023年2月期间收治的127例结肠癌病人作为研究组,89例结肠良性病变病人作为结肠良性病变组,同期本院体检的127例健康者作为对照组。以血清miR-448(1.12)和miR-153(0.98)表达水平的中位数为临界值将研究组病人分为miR-448高表达组(63例)、miR-448低表达组(64例),miR-153高表达组(64例)、miR-153低表达组(63例)。Pearson法分析血清miR-448和miR-153表达水平与结肠癌病人肠道菌群、免疫功能指标的相关性;受试者工作特征(ROC)曲线分析血清miR-448和miR-153对结肠癌的诊断价值。结果研究组、结肠良性病变组、对照组大肠杆菌、双歧杆菌、双歧杆菌/大肠杆菌比值以及免疫球蛋白IgG、IgM、IgA比较,差异有统计学意义(P<0.05);研究组血清miR-448表达水平为(1.25±0.22),高于对照组的(1.09±0.03)和结肠良性病变组的(1.18±0.15),血清miR-153表达水平为(0.89±0.12)低于对照组的(1.03±0.17)和结肠良性病变组的(0.96±0.16);血清miR-448、miR-153高表达和低表达组大肠杆菌、双歧杆菌、双歧杆菌/大肠杆菌比值、IgG、IgM、IgA表达水平比较,差异有统计学意义(P<0.05);血清miR-448、miR-153与大肠杆菌、双歧杆菌、双歧杆菌/大肠杆菌比值有相关性(r=0.657,-0.742,-0.753;r=-0.711,0.813,0.771,P<0.05);IgG、IgM、IgA与血清miR-448呈正相关(r=0.686,0.709,0.744),与miR-153呈负相关(r=-0.690,-0.841,-0.769,P<0.05);血清miR-448和miR-153联合检测诊断结肠癌的AUC为0.845,优于各自单独检测(Z二者联合-miR-448=4.561、Z二者联合-miR-153=2.426,P=0.000、0.015)。结论结肠癌病人血清miR-448和miR-153表达水平与肠道菌群及免疫功能有相关性,二者联合对结肠癌具有较高的诊断价值。

结肠癌患者肿瘤浸润淋巴细胞表型与临床病理特征和肠道菌群的关系研究

目的探究结肠癌患者肿瘤浸润淋巴细胞(TIL)表型与临床病理特征和肠道菌群的关系。方法选取2017年6月至2023年2月湖北省十堰市太和医院收治的76例结肠癌患者为结肠癌组,并选择同期体检的76例健康人为对照组。检测两组受试者TIL表型表达水平,荧光定量PCR检测肠道菌群,收集结肠癌患者临床病理资料。采用Spearman分析TIL表型与肠道菌群的相关性。结果与对照组相比,结肠癌组CD4^(+)T细胞水平显著升高[(28.05±5.48)%比(32.49±6.13)%],CD3^(+)T细胞、CD8^(+)T细胞水平显著降低[(60.47±6.53)%比(53.17±6.37)%]、[(30.69±6.38)%比(24.85±6.42)%](P<0.05)。根据结肠癌患者CD3^(+)T细胞(52.62%)、CD8^(+)T细胞(25.87%)、CD4^(+)T细胞(31.94%)的中位值,将其分为CD3^(+)T细胞高表达38例,CD3^(+)T细胞低表达38例,CD8^(+)T细胞高表达38例,CD8^(+)T细胞低表达38例,CD4^(+)T细胞高表达38例,CD4^(+)T细胞低表达38例。有淋巴结转移、肿瘤分化程度越高、TNM分期越高,在CD3^(+)T细胞、CD8^(+)T细胞、CD4^(+)T细胞高表达、低表达患者间差异有统计学意义(χ2=5.330、4.659、6.786;χ2=7.962、10.483、4.343;χ2=11.120、7.280、13.300;P<0.05)。与对照组相比,结肠癌组脆弱拟杆菌、大肠埃希菌、肠球菌数量显著增加[(6.58±0.83)lgN/g比(8.59±1.36)lgN/g]、[(7.36±1.04)lgN/g比(9.73±1.25)lgN/g]、[(7.21±1.08)lgN/g比(9.28±1.74)lgN/g],乳酸杆菌、双歧杆菌数量显著下降[(8.85±1.46)lgN/g比(6.34±1.22)lgN/g]、[(8.94±1.09)lgN/g比(6.17±1.32)lgN/g](P<0.05)。Spearman相关分析结果显示,结肠癌患者脆弱拟杆菌、大肠埃希菌、肠球菌与CD3^(+)、CD8^(+)T细胞占比呈负相关(r=-0.482、-0.459、-0.532,P<0.05;r=-0.438、-0.472、-0.508,P<0.05),乳酸杆菌、双歧杆菌与CD3^(+)、CD8^(+)T细胞占比呈正相关(r=0.581、0.507,P<0.05;r=0.536、0.467,P<0.05),脆弱拟杆菌、大肠埃希菌、肠球菌与CD4^(+)T细胞占比呈正相关(r=0.483、0.495、0.461,P<0.05),乳酸杆菌、双歧杆菌与CD4^(+)T细胞占比呈负相关(r=-0.563、-0.579,P<0.05)。结论结肠癌患者TIL中表型CD3^(+)T细胞、CD8^(+)T细胞、CD4^(+)T细胞与临床病理特征和肠道菌群存在一定关系。

顽固性便秘病人结肠黏膜菌群的变化特征

目的:阐释顽固性便秘病人结肠黏膜菌群的变化特征。方法:本研究分为顽固性便秘组(n=10)和对照组(n=6)。通过结肠镜活检获取乙状结肠黏膜标本,提取DNA,PCR扩增后行变性梯度凝胶电泳,应用分子生物学分析软件对菌群结构的相似性、主成分和多样性进行分析。结果:顽固性便秘病人结肠黏膜菌群有明显改变,与对照组比,顽固性便秘病人结肠黏膜菌群物种丰富度和香农多样性指数均显著降低(P<0.01)。结论:顽固性便秘病人结肠黏膜菌群紊乱,表现为结肠黏膜菌群多样性减少。

婴幼儿肠道微生物的定植特征

肠道微生物对人体的健康至关重要。婴儿肠道微生物的丰度、多样性以及构成变化较大,这些变化受母体、分娩、喂养、医疗、环境等因素影响。因此,婴幼儿肠道菌群的定植和变化标准是很难定义的。本文对早期婴幼儿肠道菌群定植与发展、微生物代谢产物的最新研究进展进行了论述。

谷物膳食纤维与结肠健康

膳食纤维(DF)为微生物生长提供均衡的能量和营养,这是维持结肠生态系统平衡所必需的。另外,膳食纤维的发酵,特别是丁酸发酵,有利于结肠健康。目前,结肠癌、炎症性肠炎和其他结肠紊乱疾病已经严重影响身体健康。作者综述了谷物膳食纤维中非淀粉谷物多聚糖、抗性淀粉,通过发酵产物短链脂肪酸和菌群的调节对于结肠健康的影响。

5'-核苷酸对慢性酒精中毒诱导大鼠结肠功能损伤的影响

探讨外源性5'-核苷酸对酒精诱导大鼠结肠功能紊乱的保护作用。50只SPF级雄性Wistar大鼠随机分为正常对照组、酒精模型组、等热量对照组及0.04%、0.16%核苷酸组。连续酒精灌胃6周后,结果发现,外源性5'-核苷酸能够有效改善酒精引起的大鼠结肠病理性改变,显著提高结肠功能相关蛋白Claudin和Occludin的表达水平(p<0.01或p<0.05),极显著降低大鼠结肠组织中Toll样受体4(TLR4)和分化抗原簇14(CD14)的表达水平(p<0.01);外源性5'-核苷酸能够显著增加大鼠回肠内容物中双歧杆菌(酒精组8.00 log CFU/g,核苷酸组8.32 log CFU/g)和乳酸杆菌数量(酒精组7.44 log CFU/g,核苷酸组8.13 log CFU/g)(p<0.05),同时显著减少肠球菌(酒精组7.52 log CFU/g,核苷酸组7.03 log CFU/g)及大肠杆菌数量(酒精组6.85 log CFU/g,核苷酸组6.19 log CFU/g)(p<0.05)。因此,外源性5'-核苷酸能够通过调节肠道菌群改善酒精引起的大鼠结肠损伤。