The Differences between Luminal Microbiota and Mucosal Microbiota in Mice

Minna Wu,Puze Li,Jianmin Li,Yunying An,Mingyong Wang,Genshen Zhong 한국미생물·생명공학회 2020 Journal of microbiology and biotechnology Vol.30 No.2

The differences between luminal microbiota (LM) and mucosal microbiota (MAM) were little known, especially in duodenum. In this study, LM and MAM in colon and duodenum of mice were investigated through 16S rRNA high-throughput sequencing. The lowest bacterial diversity and evenness were observed in duodenal LM (D_LM), followed by duodenal MAM (D_MAM). Meanwhile, the bacterial diversity and evenness were obviously increased in D_MAM than these in D_LM, while no significant difference was observed between colonic MAM (C_MAM) and colonic LM (C_LM). PCoA analysis also showed that bacterial communities of LM and MAM in duodenum were completely separated, while these in colon overlapped partly. The ratio of Firmicutes to Bacteroidetes (F/B) in D_MAM was significantly higher than that in D_LM. Lactobacillus was largely enriched and was the characteristic bacteria in D_LM. The characteristic bacteria in D_MAM were Turicibacter, Parasutterella, Marvinbryantia and Bifidobacterium, while in C_LM they were Ruminiclostridium_6, Ruminiclostridium_9, Ruminococcaceae_UCG_007 and Lachnospiraceae_UCG_010, and in C_MAM they were Lachnospiraceae_NK4A136, Mucispirillum, Alistipes, Ruminiclostridium and Odoribacter. The networks showed that more interactions existed in colonic microbiota (24 nodes and 74 edges) than in duodenal microbiota (17 nodes and 29 edges). The 16S rDNA function prediction results indicated that bigger differences of function exist between LM and MAM in duodenum than these in colon. In conclusion, microbiota from intestinal luminal content and mucosa were different both in colon and in duodenum, and bacteria in colon interacted with each other much more closely than those in duodenum.

Comparison of Microbial Diversity and Composition in the Jejunum and Colon of Alcohol-Dependent Rats

( Yang Fan ),( Zhao Ya-e ),( Wei Ji-dong ),( Lu Yu-fan ),( Zhang Ying ),( Sun Ya-lun ),( Ma Meng-yu ),( Zhang Rui-ling ) 한국미생물생명공학회(구 한국산업미생물학회) 2018 Journal of microbiology and biotechnology Vol.28 No.11

Alcohol dependence is a global public health problem, yet the mechanisms of alcohol dependence are incompletely understood. The traditional view has been that ethanol alters various neurotransmitters and their receptors in the brain and causes the addiction. However, an increasing amount of experimental evidence suggests that gut microbiota also influence brain functions via gut-to-brain interactions, and may therefore induce the development of alcohol use disorders. In this study, a rat model of alcohol dependence and withdrawal was employed, the gut microbiota composition was analyzed by high-throughput 16S rRNA gene sequencing, and the metagenome function was predicted by PICRUSt software. The results suggested that chronic alcohol consumption did not significantly alter the diversity and richness of gut microbiota in the jejunum and colon, but rather markedly changed the microbiota composition structure in the colon. The phyla Bacteroidetes and eight genera including Bacteroidales S24-7, Ruminococcaceae, Parabacteroides, Butyricimonas, et al were drastically increased, however the genus Lactobacillus and gauvreauii in the colon were significantly decreased in the alcohol dependence group compared with the withdrawal and control groups. The microbial functional prediction analysis revealed that the proportions of amino acid metabolism, polyketide sugar unit biosynthesis and peroxisome were significantly increased in the AD group. This study demonstrated that chronic alcohol consumption has a dramatic effect on the microbiota composition structure in the colon but few effects on the jejunum. Inducement of colonic microbiota dysbiosis due to alcohol abuse seems to be a factor of alcohol dependence, which suggests that modulating colonic microbiota composition might be a potentially new target for treating alcohol addiction.

Comparisons of Gut Microbiota Among Healthy Control, Patients With Conventional Adenoma, Sessile Serrated Adenoma, and Colorectal Cancer

윤혁,김나영,박지현,김용성,이종찬,김형우,최윤진,신철민,박영수,이동호,정현채 대한암예방학회 2017 Journal of cancer prevention Vol.22 No.2

Background: Studies on gut microbiota regarding colorectal carcinogenesis, including sessile serrated adenoma (SSA), have been scarce. The aim of this study is to investigate the role of mucosa-associated gut microbiota in the colorectal carcinogenesis. Methods: We collected biopsy samples of normal rectal mucosa during colonoscopy from healthy control and patients with conventional adenoma, SSA, and colorectal cancer (CRC), respectively (n = 6). Pyrosequencing for 16S rRNA gene of bacteria was performed to compare gut microbiota. Results: The most abundant phylum in total samples was Proteobacteria (55.6%), followed by Firmicutes (27.4%) and Bacteroidetes (11.6%). There was no significant difference in relative abundance of the phylum level among the four groups. Fusobacterium nucleatum, known to be frequently detected during colorectal carcinogenesis, was found in only one sample of patient with SSA. The rarefaction curves showed that the diversity of mucosal communities of patients with CRC is the lowest among the four groups and the diversity of mucosal communities of patients with SSA is higher than that of healthy control. Among the four groups, Shannon’s and Simpson’s index for diversity was the lowest and the highest in the patients with CRC, respectively; it did not reach statistical significance. The proportion of genus Pseudomonas was very high in the samples of patients with stage II-IV CRC compared with those with stage I CRC (59.3% vs. 0.3%, P = 0.064). Conclusions: Our study suggests no significant role of mucosa-associated gut microbiota in the colorectal carcinogenesis. Further study for many samples or using fecal material could be helpful.

Role of melatonin in murine “restraint stress”-induced dysfunction of colonic microbiota

Lin Rutao,Wang Zixu,Cao Jing,Gao Ting,Dong Yulan,Chen Yaoxing 한국미생물학회 2021 The journal of microbiology Vol.59 No.5

Intestinal diseases caused by physiological stress have become a severe public health threat worldwide. Disturbances in the gut microbiota-host relationship have been associated with irritable bowel disease (IBD), while melatonin (MT) has antiinflammatory and antioxidant effects. The objective of this study was to investigate the mechanisms by which MT-mediated protection mitigated stress-induced intestinal microbiota dysbiosis and inflammation. We successfully established a murine restraint stress model with and without MT supplementation. Mice subjected to restraint stress had significantly elevated corticosterone (CORT) levels, decreased MT levels in their plasma, elevated colonic ROS levels and increased bacterial abundance, including Bacteroides and Tyzzerella, in their colon tract, which led to elevated expression of Toll-like receptor (TLR) 2/4, p-P65 and p-IκB. In contrast, supplementation with 20 mg/kg MT reversed the elevation of the plasma CORT levels, downregulated the colon ROS levels and inhibited the changes in the intestinal microbiota induced by restraint stress. These effects, in turn, inhibited the activities of TLR2 and TLR4, p-P65 and p-IκB, and decreased the inflammatory reaction induced by restraint stress. Our results suggested that MT may mitigate “restraint stress”-induced colonic microbiota dysbiosis and intestinal inflammation by inhibiting the activation of the NF-κB pathway.

Combined effects of BARLEYmax and cocoa polyphenols on colonic microbiota and bacterial metabolites in vitro

Ryuji Nagata,Shun Sato,Aldrine Kilua,Naoki Fukuma,Yasunori Nakayama,Eiichi Kitazono,Toshiaki Aoyama,Kyu Ho Han,Michihiro Fukushima 한국식품과학회 2021 Food Science and Biotechnology Vol.30 No.11

BARLEYmax, a barley variety, and cocoapolyphenols (CPPs) have been reported to affect bacterialmetabolites in the colon. This study aimed to evaluate thecombined effects of BARLEYmax and CPPs supplementationon fecal microbiota in vitro using pig feces for 48 h. The relative abundances of the family Clostridiaceae andthe genus Clostridium and ammonia–nitrogen productionwere decreased by both BARLEYmax and CPP supplementation,and there was a positive correlation betweentheir abundances and the ammonia–nitrogen concentration. Although acetate and n-butyrate production was decreasedby CPP supplementation, their concentrations were maintainedat a higher level in the BARLEYmax ? CPP groupthan in the cellulose (control) and cellulose ? CPP groups. Therefore, this study demonstrated that a combination ofBARLEYmax and CPPs may be beneficial in maintaininghigher short-chain fatty acid production and the eliminationof potentially harmful factors.

A double blind, placebo-controlled, randomized clinical trial that breast milk derived- <i>Lactobacillus gasseri</i> BNR17 mitigated diarrhea-dominant irritable bowel syndrome

Shin, Suk Pyo,Choi, Yoon Mi,Kim, Won Hee,Hong, Sung Pyo,Park, Jong-Min,Kim, Joohee,Kwon, Oran,Lee, Eun Hyun,Hahm, Ki Baik the Society for Free Radical Research Japan 2018 Journal of clinical biochemistry and nutrition Vol.62 No.2

<P>The exact pathogenesis of diarrhea-dominant irritable bowel syndrome (IBS) is not known, but the abnormal microbiota of the gastrointestinal tract is considered to be one of the important contributing factors as in other gastrointestinal diseases such as inflammatory bowel disease, antibiotic-associated diarrhea, and colorectal cancer as well as systemic diseases. Though diverse trials of probiotics had been continued in the treatment of diarrhea-IBS, only a few proved by randomized clinical trial. To prove the efficacy of <I>Lactobacillus gasseri</I> BNR17 isolated from breast milk in patients with diarrhea-IBS, prospective, randomized, placebo controlled clinical trial was done including health related-quality of life analysis, colon transit time, and the changes of fecal microbiota. BNR17 significantly improved the symptoms of diarrhea compared to control group. Health related-QOL analysis showed significant improvement of abdominal pain, distension, disturbed daily life, and mean defecation frequency with BNR17. On comparative CTT before and after BNR17, 6 out of 24 subjects showed significant correction of rapid colon transit pattern, while only 2 out of 24 in placebo (<I>p</I><0.01). Upon fecal microbiota analysis, BNR17 significantly increased <I>B. fecalis</I>, <I>E. rectale</I>, <I>C. aerofaciens</I>, <I>F. prausnitzil</I> and <I>B. steroris</I>. Conclusively, <I>Lactobacillus gasseri</I> BNR17 can be a potential probiotics to ameliorate diarrhea-IBS.</P>

Effect of increasing levels of rice distillers' by-product on growth performance, nutrient digestibility, blood profile and colonic microbiota of weaned piglets

Cong, Oanh Nguyen,Taminiau, Bernard,Kim, Dang Pham,Daube, Georges,Van, Giap Nguyen,Bindelle, Jerome,Fall, Papa Abdulaye,Dinh, Ton Vu,Hornick, Jean-Luc Asian Australasian Association of Animal Productio 2020 Animal Bioscience Vol.33 No.5

Objective: This study was conducted to evaluate the effects of diets containing different wet rice distillers' by-product (RDP) levels on growth performance, nutrient digestibility, blood profiles and gut microbiome of weaned piglets. Methods: A total of 48 weaned castrated male crossbred pigs, initial body weight 7.54±0.97 kg, and age about 4 wks, were used in this experiment. The piglets were randomly allocated into three iso-nitrogenous diet groups that were fed either a control diet, a diet with 15% RDP, or a diet with 30% RDP for a total of 35 days. Chromium oxide was used for apparent digestibility measurements. On d 14 and d 35, half of the piglets were randomly selected for hemato-biochemical and gut microbiota evaluations. Results: Increasing inclusion levels of RDP tended to linearly increase (p≤0.07) average daily gain on d 14 and d 35, and decreased (p = 0.08) feed conversion ratio on d 35. Empty stomach weight increased (p = 0.03) on d 35 while digestibility of diet components decreased. Serum globulin concentration decreased on d 14 (p = 0.003) and red blood cell count tended to decrease (p = 0.06) on d 35, parallel to increase RDP levels. Gene amplicon profiling of 16S rRNA revealed that the colonic microbiota composition of weaned pigs changed by inclusion of RDP over the period. On d 14, decreased proportions of Lachnospiraceae_ge, Ruminococcaceae_ge, Ruminococcaceae_UCG-005, and Bacteroidales_ge, and increased proportions of Prevotellaceae_ge, Prevotella_2, and Prevotella_9 were found with inclusion of RDP, whereas opposite effect was found on d 35. Additionally, the proportion of Lachnospiraceae_ge, Ruminococcaceae_ge, Ruminococcaceae_UCG-005, and Bacteroidales_ge in RDP diets decreased over periods in control diet but increased largely in diet with 30% RDP. Conclusion: These results indicate that RDP in a favorable way modulate gastrointestinal microbiota composition and improve piglet performance despite a negative impact on digestibility of lipids and gross energy.

The Effect of Microbiota on Colon Carcinogenesis

Yoon, Kichul,Kim, Nayoung Korean Society of Cancer Prevention 2018 Journal of cancer prevention Vol.23 No.3

<P>Although genetic background is known to contribute to colon carcinogenesis, the exact etiology of the disease remains elusive. The organ’s extensive interaction with microbes necessitated research on the role of microbiota on development of colon cancer. In this review, we summarized the defense mechanism of colon from foreign organism, and germ-free animal models that have been employed to elucidate microbial effect. We also comprehensively discussed the metabolic property of microbiota such as butyrate production, facilitation of heme toxicity, bile acid transformation, and nitrate reduction that has been shown to contribute to the development of the tumor. Finally, up-to-date subjects such as the effect of age and gender on microbiota are briefly discussed.</P>

장내 다제내성균 탈집락화를 위한 대변 세균총 이식: 체계적 문헌고찰

이슬기,최지은,신채민,김미나 대한임상미생물학회 2021 Annals of clinical microbiology Vol.24 No.3

Background: Fecal microbiota transplantation against gut colonization using a multidrugresistantorganism is a technique used to treat infections through normalizing the gutmicrobiota via fecal microbiota transplantation in patients with confirmed colonization bycarbapenem-resistant Enterobacteriaceae (CRE) or vancomycin-resistant enterococci (VRE)based on a fecal culture test within the past one week. In this study, we aimed to determinethe safety and effectiveness of this technique. Methods: The safety and effectiveness were assessed via a systematic review. A literaturesearch was conducted using five Korean databases, such as KoreaMed, and internationaldatabases, including Ovid-MEDLINE, Ovid-EMBASE, and Cochrane Library. Results: Main results are described here. From the studies retrieved using the aforementionedsearch strategy, the remaining 581 studies were screened using the inclusion and exclusioncriteria, resulting in the selection of nine studies for further consideration. In terms of safety,many studies reported deaths and adverse reactions associated with different causes. Fewerstudies reported the rate of colonization; however, the effect of colony rate was inconsistentwhen compared to no treatment group. Additionally, none of the studies assessed therecurrence rate, a decrease in the prevalence of diseases related to infection by multidrugresistantbacteria, and the quality of life. Conclusion: Fecal bacterial colonization for the decolonization of intestinal multidrugresistantbacteria was evaluated using a technique that requires further research as there isinsufficient literature evidence to validate its safety and efficacy in treating infections throughnormalizing the intestinal flora of patients with confirmed colonization by CRE or VRE.

Molecular Analysis of Colonized Bacteria in a Human Newborn Infant Gut

Hee-Kyung Park,Sung-Sub Shim,Su-Yung Kim,Jae-Hong Park,Su-Eun Park,Hak-Jung Kim,강병철,Cheol-Min Kim 한국미생물학회 2005 The journal of microbiology Vol.43 No.4

The complex ecosystem of intestinal microflora is estimated to harbor approximately 400 different microbial species, mostly bacteria. However, studies on bacterial colonization have mostly been based on culturing methods, which only detect a small fraction of the whole microbiotic ecosystem of the gut. To clarify the initial acquisition and subsequent colonization of bacteria in an infant within the few days after birth, phylogenetic analysis was performed using 16S rDNA sequences from the DNA isolated from feces on the 1st, 3rd, and 6th day. 16S rDNA libraries were constructed with the amplicons of PCR conditions at 30 cycles and 50oC annealing temperature. Nine independent libraries were produced by the application of three sets of primers (set A, set B, and set C) combined with three fecal samples for day 1, day 3, and day 6 of life. Approximately 220 clones (76.7%) of all 325 isolated clones were characterized as known species, while other 105 clones (32.3%) were characterized as unknown species. The library clone with set A universal primers amplifying 350 bp displayed increased diversity by days. Thus, set A primers were better suited for this type of molecular ecological analysis. On the first day of the life of the infant, Enterobacter, Lactococcus lactis, Leuconostoc citreum, and Streptococcus mitis were present. The largest taxonomic group was L. lactis. On the third day of the life of the infant, Enterobacter, Enterococcus faecalis, Escherichia coli, S. mitis, and treptococcus salivarius were present. On the sixth day of the life of the infant, Citrobacter, Clostridium difficile, Enterobacter sp., Enterobacter cloacae, and E. coli were present. The largest taxonomic group was E. coli. These results showed that microbiotic diversity changes very rapidly in the few days after birth, and the acquisition of unculturable bacteria expanded rapidly after the third day. The complex ecosystem of intestinal microflora is estimated to harbor approximately 400 different microbial species, mostly bacteria. However, studies on bacterial colonization have mostly been based on culturing methods, which only detect a small fraction of the whole microbiotic ecosystem of the gut. To clarify the initial acquisition and subsequent colonization of bacteria in an infant within the few days after birth, phylogenetic analysis was performed using 16S rDNA sequences from the DNA isolated from feces on the 1st, 3rd, and 6th day. 16S rDNA libraries were constructed with the amplicons of PCR conditions at 30 cycles and 50oC annealing temperature. Nine independent libraries were produced by the application of three sets of primers (set A, set B, and set C) combined with three fecal samples for day 1, day 3, and day 6 of life. Approximately 220 clones (76.7%) of all 325 isolated clones were characterized as known species, while other 105 clones (32.3%) were characterized as unknown species. The library clone with set A universal primers amplifying 350 bp displayed increased diversity by days. Thus, set A primers were better suited for this type of molecular ecological analysis. On the first day of the life of the infant, Enterobacter, Lactococcus lactis, Leuconostoc citreum, and Streptococcus mitis were present. The largest taxonomic group was L. lactis. On the third day of the life of the infant, Enterobacter, Enterococcus faecalis, Escherichia coli, S. mitis, and treptococcus salivarius were present. On the sixth day of the life of the infant, Citrobacter, Clostridium difficile, Enterobacter sp., Enterobacter cloacae, and E. coli were present. The largest taxonomic group was E. coli. These results showed that microbiotic diversity changes very rapidly in the few days after birth, and the acquisition of unculturable bacteria expanded rapidly after the third day.