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Frontiers in Microbiology 2023Understanding the relationships between social stress and the gastrointestinal microbiota, and how they influence host health and performance is expected to have many...
Understanding the relationships between social stress and the gastrointestinal microbiota, and how they influence host health and performance is expected to have many scientific and commercial implementations in different species, including identification and improvement of challenges to animal welfare and health. In particular, the study of the stress impact on the gastrointestinal microbiota of pigs may be of interest as a model for human health. A porcine stress model based on repeated regrouping and reduced space allowance during the last 4 weeks of the finishing period was developed to identify stress-induced changes in the gut microbiome composition. The application of the porcine stress model resulted in a significant increase in salivary cortisol concentration over the course of the trial and decreased growth performance and appetite. The applied social stress resulted in 32 bacteria being either enriched (13) or depleted (19) in the intestine and feces. Fecal samples showed a greater number of microbial genera influenced by stress than caecum or colon samples. Our trial revealed that the opportunistic pathogens and were enriched in colonic and fecal samples from stressed pigs. Additionally, genera such as , , , , , and were found to be enriched in response to social stress. In contrast, the genera , , , , , , and were depleted. These depleted bacteria are of great interest because they synthesize metabolites [e.g., short-chain fatty acids (SCFA), in particular, butyrate] showing beneficial health benefits due to inhibitory effects on pathogenic bacteria in different animal species. Of particular interest are and , as their depletion was identified in a human study to be associated with inferior quality of life and depression. We also revealed that some pigs were more susceptible to pathogens as indicated by large enrichments of opportunistic pathogens of and . Generally, our results provide further evidence for the microbiota-gut-brain axis as indicated by an increase in cortisol concentration due to social stress regulated by the hypothalamic-pituitary-adrenal axis, and a change in microbiota composition, particularly of bacteria known to be associated with pathogenicity and mental health diseases.
PubMed: 38029169
DOI: 10.3389/fmicb.2023.1197371 -
Animal Nutrition (Zhongguo Xu Mu Shou... Mar 2021This review aims to give an overview of the efficacy of yeast supplementation on growth performance, rumen pH, rumen microbiota, and their relationship to meat and milk... (Review)
Review
This review aims to give an overview of the efficacy of yeast supplementation on growth performance, rumen pH, rumen microbiota, and their relationship to meat and milk quality in ruminants. The practice of feeding high grain diets to ruminants in an effort to increase growth rate and weight gain usually results in excess deposition of saturated fatty acids in animal products and increased incidence of rumen acidosis. The supplementation of yeast at the right dose and viability level could counteract the acidotic effects of these high grain diets in the rumen and positively modify the fatty acid composition of animal products. Yeast exerts its actions by competing with lactate-producing ( and ) bacteria for available sugar and encouraging the growth of lactate-utilising bacteria (). is known to convert lactate into butyrate and propionate leading to a decrease in the accumulation of lactate thereby resulting in higher rumen pH. Interestingly, this creates a conducive environment for the proliferation of vaccenic acid-producing bacteria () and ciliate protozoa, both of which have been reported to increase the ruminal concentration of -11 and -9, -11-conjugated linoleic acid (CLA) at a pH range between 5.6 and 6.3. The addition of yeast into the diet of ruminants has also been reported to positively modify rumen biohydrogenation pathway to synthesise more of the beneficial biohydrogenation intermediates ( 11 and 9, 11). This implies that more dietary sources of linoleic acid, linolenic acid, and oleic acid along with beneficial biohydrogenation intermediates (-9, -11-CLA, and -11) would escape complete biohydrogenation in the rumen to be absorbed into milk and meat. However, further studies are required to substantiate our claim. Therefore, techniques like transcriptomics should be employed to identify the mRNA transcript expression levels of genes like stearoyl-CoA desaturase fatty acid synthase, and elongase of very long chain fatty acids 6 in the muscle. Different strains of yeast need to be tested at different doses and viability levels on the fatty acid profile of animal products as well as its vaccenic acid and rumenic acid composition.
PubMed: 33997329
DOI: 10.1016/j.aninu.2020.10.005 -
The Journal of Infectious Diseases Mar 2021Vaginal yeast is frequently found with Lactobacillus-dominant microbiota. The relationship between vaginal yeast and other bacteria has not been well characterized.
BACKGROUND
Vaginal yeast is frequently found with Lactobacillus-dominant microbiota. The relationship between vaginal yeast and other bacteria has not been well characterized.
METHODS
These analyses utilized data from the Preventing Vaginal Infections trial. Relative abundance of vaginal bacteria from 16S ribosomal ribonucleic acid gene amplicon sequencing and quantities of 10 vaginal bacteria using taxon-directed polymerase chain reaction assays were compared at visits with and without detection of yeast on microscopy, culture, or both.
RESULTS
Higher relative abundances of Megasphaera species type 1 (risk ratio [RR], 0.70; 95% confidence interval [CI], 0.52-0.95), Megasphaera species type 2 (RR, 0.81; 95% CI, 0.67-0.98), and Mageeibacillus indolicus (RR, 0.46; 95% CI, 0.25-0.83) were associated with lower risk of detecting yeast. In contrast, higher relative abundances of Bifidobacterium bifidum, Aerococcus christensenii, Lactobacillus mucosae, Streptococcus equinus/infantarius/lutentiensis, Prevotella bivia, Dialister propionicifaciens, and Lactobacillus crispatus/helveticus were associated with yeast detection. Taxon-directed assays confirmed that increasing quantities of both Megasphaera species and M indolicus were associated with lower risk of detecting yeast, whereas increasing quantities of L crispatus were associated with higher risk of detecting yeast.
CONCLUSIONS
Despite an analysis that examined associations between multiple vaginal bacteria and the presence of yeast, only a small number of vaginal bacteria were strongly and significantly associated with the presence or absence of yeast.
Topics: Bacteria; Female; Humans; Megasphaera; Microbiota; RNA, Ribosomal, 16S; Vagina; Vaginosis, Bacterial; Yeasts
PubMed: 32726445
DOI: 10.1093/infdis/jiaa459 -
Biomedicines Nov 2022The role of gut microbes has been suggested in type 2 diabetes (T2DM) risk. However, their results remain controversial. We hypothesized that Asians with T2DM had...
The role of gut microbes has been suggested in type 2 diabetes (T2DM) risk. However, their results remain controversial. We hypothesized that Asians with T2DM had different fecal bacterial compositions, co-abundance networks, and metagenome functions compared to healthy individuals, according to enterotypes. This hypothesis was examined using the combined gut microbiota data from human fecal samples from previous studies. The human fecal bacterial FASTA/Q files from 36 different T2DM studies in Asians were combined (healthy, n = 3378; T2DM, n = 551), and operational taxonomic units (OTUs) and their counts were obtained using qiime2 tools. In the machine learning approaches, fecal bacteria rich in T2DM were found. They were separated into two enterotypes, Lachnospiraceae (ET-L) and Prevotellaceae (ET-P). The Shannon and Chao1 indices, representing α-diversity, were significantly lower in the T2DM group compared to the healthy group in ET-L (p < 0.05) but not in ET-P. In the Shapley additive explanations analysis of ET-L, Escherichia fergusonii, Collinsella aerofaciens, Streptococcus vestibularis, and Bifidobacterium longum were higher (p < 0.001), while Phocaeicola vulgatus, Bacteroides uniformis, and Faecalibacterium prausnitzii were lower in the T2DM group than in the healthy group (p < 0.00005). In ET-P, Escherichia fergusonii, Megasphaera elsdenii, and Oscillibacter valericigenes were higher, and Bacteroides koreensis and Faecalibacterium prausnitzii were lower in the T2DM group than in the healthy group. In ET-L and ET-P, bacteria in the healthy and T2DM groups positively interacted with each other within each group (p < 0.0001) but negatively interacted between the T2DM and healthy groups in the network analysis (p < 0.0001). In the metagenome functions of the fecal bacteria, the gluconeogenesis, glycolysis, and amino acid metabolism pathways were higher, whereas insulin signaling and adenosine 5′ monophosphate-activated protein kinase (AMPK) signaling pathways were lower in the T2DM group than in the healthy group for both enterotypes (p < 0.00005). In conclusion, Asians with T2DM exhibited gut dysbiosis, potentially linked to intestinal permeability and the enteric vagus nervous system.
PubMed: 36428566
DOI: 10.3390/biomedicines10112998 -
Applied and Environmental Microbiology Jan 2024Butyrate, a physiologically active molecule, can be synthesized through metabolic interactions among colonic microorganisms. Previously, in a fermenting trial of human...
Butyrate, a physiologically active molecule, can be synthesized through metabolic interactions among colonic microorganisms. Previously, in a fermenting trial of human fecal microbiota, we observed that the butyrogenic effect positively correlated with the increasing population and an unidentified species. Therefore, we hypothesized that a cross-feeding phenomenon exists between and , where is the butyrate producer, and its growth relies on the metabolites generated by . To validate this hypothesis, three bacterial species (, , and ) were isolated from fecal cultures fermenting hydrolyzed xylan; pairwise cocultures were conducted between the and isolates; the microbial interactions were determined based on bacterial genome information, cell growth, substrate consumption, metabolite quantification, and metatranscriptomics. The results indicated that two isolates contained distinct gene clusters for xylan utilization and expressed varying substrate preferences. In contrast, alone scarcely grew on the xylose-based substrates. The growth of was significantly elevated by coculturing it with bifidobacteria, while the two species responded differently in the kinetics of cell growth and substrate consumption. Coculturing led to the depletion of lactate and increased the formation of butyrate. An RNA-seq analysis further revealed the upregulation of genes involved in the lactate utilization and butyrate formation pathways. We concluded that lactate generated by through catabolizing xylose fueled the growth of and triggered the synthesis of butyrate. Our findings demonstrated a novel cross-feeding mechanism to generate butyrate in the human colon.IMPORTANCEButyrate is an important short-chain fatty acid that is produced in the human colon through microbial fermentation. Although many butyrate-producing bacteria exhibit a limited capacity to degrade nondigestible food materials, butyrate can be formed through cross-feeding microbial metabolites, such as acetate or lactate. Previously, the literature has explicated the butyrate-forming links between and and between and . In this study, we provided an alternative butyrate synthetic pathway through the interaction between and is a species named in 2014 and is indigenous to the human intestinal tract. Scientific studies explaining the function of in the human colon are still limited. Our results show that proliferated based on the lactate generated by bifidobacteria and produced butyrate as its end metabolic product. The pathways identified here may contribute to understanding butyrate formation in the gut microbiota.
Topics: Humans; Lactic Acid; Bifidobacterium; Xylans; Xylose; Butyrates; Megasphaera; Fermentation
PubMed: 38126785
DOI: 10.1128/aem.01019-23 -
Nan Fang Yi Ke Da Xue Xue Bao = Journal... Jun 2021To explore the differences in gut virome and microbiome between patients with stroke and healthy volunteers.
OBJECTIVE
To explore the differences in gut virome and microbiome between patients with stroke and healthy volunteers.
OBJECTIVE
Fifteen patients with acute ischemic stroke treated in the Department of Neurology of Nanfang Hospital between February, 2014 and February, 2016 and 15 healthy volunteers matched for age and sex were enrolled in this study. Virome sequencing and 16S rRNA sequencing were performed on stool samples of all the participants, and the composition and structures of the virome and microbiome were compared between the two groups.
OBJECTIVE
No significant difference was found in the overall diversity of virome between the stroke patients and the healthy volunteers (alpha diversity: =0.320; beta diversity: =0.169, =0.037), but virome composition differed significantly between the two groups. The relative abundance of and increased significantly in patients with stroke. The structures and composition of the microbiome in patients with stroke also differed significantly from those of the healthy volunteers (alpha diversity: =0.950; beta diversity: =0.005, =0.117). The relative abundance of increased while that of decreased in patients with stroke. Correlation analysis showed that in the virome of stroke patients, the relative abundance of the phage preying was positively correlated with that of their hosts (=0.550, =0.036), while in the virome of healthy volunteers, the relative abundance of the phage preying (=0.520, =0.049), (=0.541, =0.040) and (=0.526, =0.046) were positively correlated with that of their respective hosts.
OBJECTIVE
Stroke patients have similar overall diversity of the virome to healthy volunteers but different virome composition and interaction patterns between the virome and microbiome. The gut microbiome also differs between stroke patients and healthy volunteers. The relative abundance of opportunistic pathogens increases but that of symbiotic bacteria decreases in stroke patients.
Topics: Brain Ischemia; Feces; Humans; Microbiota; RNA, Ribosomal, 16S; Stroke; Virome
PubMed: 34238738
DOI: 10.12122/j.issn.1673-4254.2021.06.08 -
Journal of Reproductive Immunology Apr 2020Dysbiosis of the vaginal microbiome as a result of overgrowth of anaerobic bacteria leads to bacterial vaginosis (BV) which is associated with increased inflammation in...
Dysbiosis of the vaginal microbiome as a result of overgrowth of anaerobic bacteria leads to bacterial vaginosis (BV) which is associated with increased inflammation in the genital mucosa. Moreover, BV increases susceptibility to sexual transmitted infections (STIs) and is associated with adverse pregnancy outcomes. It remains unclear how specific vaginal aerobic and anaerobic bacteria affect health and disease. We selected different vaginal bacteria ranging from true commensals to species associated with dysbiosis and investigated their effects on activation of dendritic cells (DCs). Commensal Lactobacilli crispatus did not induce DC maturation nor led to production of pro-inflammatory cytokines. In contrast, BV-associated bacteria Megasphaera elsdenii and Prevotella timonensis induced DC maturation and increased levels of pro-inflammatory cytokines. Notably, DCs stimulated with Prevotella timonensis suppressed Th2 responses and induced Th1 skewing, typically associated with preterm birth. In contrast, Lactobacillus crispatus and Megasphaera elsdenii did not affect Th cell polarization. These results strongly indicate that the interaction of vaginal bacteria with mucosal DCs determines mucosal inflammation and we have identified the anaerobic bacterium Prevotella timonensis as a strong inducer of inflammatory responses. Specifically targeting these inflammation-inducing bacteria might be a therapeutic strategy to prevent BV and associated risks in STI susceptibility and preterm birth.
Topics: Cells, Cultured; Cytokines; Dendritic Cells; Dysbiosis; Female; Humans; Inflammation Mediators; Leukocytes, Mononuclear; Megasphaera elsdenii; Prevotella; Primary Cell Culture; Vagina; Vaginosis, Bacterial
PubMed: 32004804
DOI: 10.1016/j.jri.2020.103085 -
Journal of Dermatological Science May 2021The gut microbiota is known to play a key role in autoimmune diseases. (Observational Study)
Observational Study
BACKGROUND
The gut microbiota is known to play a key role in autoimmune diseases.
OBJECTIVES
To identify and compare the characteristics in the gut microbial composition of patients with alopecia areata (AA) and healthy controls (HCs).
METHODS
In a cross-sectional discovery cohort, we enrolled 33 patients with AA and 35 HCs from the same geographic location in Shanghai, China. The 16S rRNA gene sequencing and bioinformatic analyses were conducted to analyze DNA extracted from the subjects.
RESULTS
The α-diversity of the AA group demonstrated no statistically significant differences compared with the HC group (P > 0.05). However, the overall gut microbial communities in the AA group were distinct from the HCs (P = 0.0096). We also adopted a random forest model to select three AA-associated OTU biomarkers: OTU1237(Achromobacter), OTU257(Megasphaera), and OTU1784(Lachnospiraceae Incertae Sedis).
CONCLUSION
The overall gut microbial composition for AA was distinct from that of HCs. The gut microbial markers we identified may potentially be used for earlier diagnosis and as therapeutic targets.
Topics: Adult; Alopecia Areata; Biomarkers; China; Cross-Sectional Studies; DNA, Bacterial; Early Diagnosis; Female; Gastrointestinal Microbiome; Healthy Volunteers; Humans; Male; Phylogeny; RNA, Ribosomal, 16S; Young Adult
PubMed: 33893030
DOI: 10.1016/j.jdermsci.2021.04.003 -
Disease Markers 2020Although intestinal microbial dysbiosis was confirmed to be associated with many chronic diseases and health status through complicated interaction with the host, the...
Although intestinal microbial dysbiosis was confirmed to be associated with many chronic diseases and health status through complicated interaction with the host, the effect on gastric cancer was less studied. In this study, we sequenced the 16S rRNA and 18S rRNA genes of fecal bacteria and fungi, respectively, in 134 gastric cancer patients and 58 healthy controls matched by age and gender. Propensity score matching (PSM) was adopted for adjusting diet habits and lifestyle, and 44 patients and 44 healthy controls (matching population) were enrolled. Serum antibody to and metabolites of the matching population were detected. The positive rates of antibody to between the patients and the control group did not reach the statistical difference. LEfSe analysis indicated that bacteria were more stable than fungi when adjusting diet and lifestyle. , , and genus and subsp. , , and species in bacteria were related to the risk of gastric cancer and showed a good diagnostic value in distinguishing the patients from healthy controls. showed a risk effect for gastric cancer; however, the effect turned into be protective after PSM. Serum L-alanine, L-threonine, and methionol were positively associated with and and several fungi genus. Overall, our findings indicated that fecal microbiome constitution alteration may be associated with gastric cancer through influencing the amino acid metabolism.
Topics: Aged; Biomarkers, Tumor; Case-Control Studies; China; Feces; Female; Helicobacter Infections; Helicobacter pylori; Humans; Male; Microbiota; Middle Aged; Stomach Neoplasms
PubMed: 33014185
DOI: 10.1155/2020/3461315 -
Letters in Applied Microbiology Jun 2015Electrospray ionization-tandem mass spectrometry (ESI-MS/MS) was used for characterizing intact plasmalogen phospholipid molecules in beer-spoilage bacteria....
Electrospray ionization-tandem mass spectrometry (ESI-MS/MS) was used for characterizing intact plasmalogen phospholipid molecules in beer-spoilage bacteria. Identification of intact plasmalogens was carried out using collision-induced dissociation and the presence of suitable marker molecular species, both qualitative and quantitative, was determined in samples containing the anaerobic bacteria Megasphaera and Pectinatus. Using selected ion monitoring (SIM), this method had a limit of detection at 1 pg for the standard, i.e. 1-(1Z-octadecenyl)-2-oleoyl-sn-glycero-3-phosphoethanolamine and be linear in the range of four orders of magnitude from 2 pg to 20 ng. This technique was applied to intact plasmalogen extracts from the samples of contaminated and uncontaminated beer without derivatization and resulted in the identification of contamination of beer by Megasphaera and Pectinatus bacteria. The limit of detection was about 830 cells of anaerobic bacteria, i.e. bacteria containing natural cyclopropane plasmalogenes (c-p-19:0/15:0), which is the majority plasmalogen located in both Megasphaera and Pectinatus. The SIM ESI-MS method has been shown to be useful for the analysis of low concentration of plasmalogens in all biological samples, which were contaminated with anaerobic bacteria, e.g. juice, not only in beer. Significance and impact of the study: Electrospray ionization-tandem mass spectrometry (ESI-MS/MS) using collision-induced dissociation was used to characterize intact plasmalogen phospholipid molecules in beer-spoilage anaerobic bacteria Megasphaera and Pectinatus. Using selected ion monitoring (SIM), this method has a detection limit of 1 pg for the standard 1-(1Z-octadecenyl)-2-oleoyl-sn-glycero-3-phosphoethanolamine and is linear within four orders of magnitude (2 pg to 20 ng). The limit of detection was about 830 cells of bacteria containing natural cyclopropane plasmalogen (c-p-19:0/15:0). SIM ESI-MS method is useful for analyzing low concentrations of plasmalogens in biological samples contaminated with anaerobic bacteria, e.g. beer or juice.
Topics: Beer; Food Microbiology; Limit of Detection; Megasphaera; Pectinatus; Plasmalogens; Spectrometry, Mass, Electrospray Ionization; Tandem Mass Spectrometry
PubMed: 25773514
DOI: 10.1111/lam.12415