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Journal of the American Heart... Nov 2015Gut microbiota has been suggested to play a role in almost all major diseases including cardio- and cerebrovascular diseases. A possible mechanism is the transformation...
BACKGROUND
Gut microbiota has been suggested to play a role in almost all major diseases including cardio- and cerebrovascular diseases. A possible mechanism is the transformation of dietary choline and l-carnitine into trimethylamine by gut bacteria. This metabolite is further oxidized into trimethylamine-N-oxide (TMAO) in liver and promotes atherogenesis. Nevertheless, little is known about gut microbial diversity and blood TMAO levels in stroke patients.
METHODS AND RESULTS
We performed a case-control study of patients with large-artery atherosclerotic ischemic stroke and transient ischemic attack. TMAO was determined with liquid chromatography tandem mass spectrometry. Gut microbiome was profiled using Illumina sequencing of the 16S rRNA V4 tag. Within the asymptomatic control group, participants with and without carotid atherosclerotic plaques showed similar levels of TMAO without a significant difference in gut microbiota; however, the gut microbiome of stroke and transient ischemic attack patients was clearly different from that of the asymptomatic group. Stroke and transient ischemic attack patients had more opportunistic pathogens, such as Enterobacter, Megasphaera, Oscillibacter, and Desulfovibrio, and fewer commensal or beneficial genera including Bacteroides, Prevotella, and Faecalibacterium. This dysbiosis was correlated with the severity of the disease. The TMAO level in the stroke and transient ischemic attack patients was significantly lower, rather than higher, than that of the asymptomatic group.
CONCLUSIONS
Participants with asymptomatic atherosclerosis did not exhibit an obvious change in gut microbiota and blood TMAO levels; however, stroke and transient ischemic attack patients showed significant dysbiosis of the gut microbiota, and their blood TMAO levels were decreased.
Topics: Aged; Aged, 80 and over; Asymptomatic Diseases; Bacteria; Carotid Artery Diseases; Case-Control Studies; Chromatography, Liquid; Down-Regulation; Dysbiosis; Feces; Female; Gastrointestinal Microbiome; Humans; Intestines; Ischemic Attack, Transient; Male; Mass Spectrometry; Methylamines; Middle Aged; Ribotyping; Stroke
PubMed: 26597155
DOI: 10.1161/JAHA.115.002699 -
EBioMedicine May 2021The relationship between tuberculosis (TB), one of the leading infectious causes of death worldwide, and the microbiome, which is critical for health, is poorly...
BACKGROUND
The relationship between tuberculosis (TB), one of the leading infectious causes of death worldwide, and the microbiome, which is critical for health, is poorly understood.
METHODS
To identify potential microbiome-host interactions, profiling of the oral, sputum and stool microbiota [n = 58 cases, n = 47 culture-negative symptomatic controls (SCs)] and whole blood transcriptome were done in pre-treatment presumptive pulmonary TB patients. This was a cross-sectional study. Microbiota were also characterised in close contacts of cases (CCCs, n = 73) and close contacts of SCs (CCSCs, n = 82) without active TB.
FINDINGS
Cases and SCs each had similar α- and β-diversities in oral washes and sputum, however, β-diversity differed in stool (PERMANOVA p = 0•035). Cases were enriched with anaerobes in oral washes, sputum (Paludibacter, Lautropia in both) and stool (Erysipelotrichaceae, Blautia, Anaerostipes) and their stools enriched in microbial genes annotated as amino acid and carbohydrate metabolic pathways. In pairwise comparisons with their CCCs, cases had Megasphaera-enriched oral and sputum microbiota and Bifidobacterium-, Roseburia-, and Dorea-depleted stools. Compared to their CCSCs, SCs had reduced α-diversities and many differential taxa per specimen type. Cases differed transcriptionally from SCs in peripheral blood (PERMANOVA p = 0•001). A co-occurrence network analysis showed stool taxa, Erysipelotrichaceae and Blautia, to negatively co-correlate with enriched "death receptor" and "EIF2 signalling" pathways whereas Anaerostipes positively correlated with enriched "interferon signalling", "Nur77 signalling" and "inflammasome" pathways; all of which are host pathways associated with disease severity. In contrast, none of the taxa enriched in SCs correlated with host pathways.
INTERPRETATION
TB-specific microbial relationships were identified in oral washes, induced sputum, and stool from cases before the confounding effects of antibiotics. Specific anaerobes in cases' stool predict upregulation of pro-inflammatory immunological pathways, supporting the gut microbiota's role in TB.
FUNDING
European & Developing Countries Clinical Trials Partnership, South African-Medical Research Council, National Institute of Allergy and Infectious Diseases.
Topics: Adult; Bacteria, Anaerobic; Female; Gastrointestinal Microbiome; Humans; Inflammasomes; Interferons; Male; Signal Transduction; Transcriptome; Tuberculosis, Pulmonary; Up-Regulation
PubMed: 33975252
DOI: 10.1016/j.ebiom.2021.103374 -
Translational Animal Science Apr 2020Simmental-Angus calves [ = 135; 72 steers and 63 heifers; body weight (BW) = 212.4 kg ± 36.1] were early weaned (~5 mo) to evaluate multiple feeding regimens...
Simmental-Angus calves [ = 135; 72 steers and 63 heifers; body weight (BW) = 212.4 kg ± 36.1] were early weaned (~5 mo) to evaluate multiple feeding regimens (conventional vs. aggressive energy diets ± NCIMB 41125 ( culture (MEC); Lactipro Advance; MS Biotec Inc., Wamego, KS) in order to elucidate the optimal development strategy. Objectives were measured by tracking the effects of caloric density and oral drenching of growing phase performance and subsequent carcass traits. The 72-d experiment featured three groups: 1) control (CON), fed exclusively a 35% roughage diet; 2) aggressive (AGR), fed a blend of a 10% and 35% roughage diets; 3) MEC, fed the same diet as AGR and drenched with 50 mL of NCIMB 41125 on day 1. A subset of calves ( = 45) was equipped with wireless rumination tags (Allflex Flex Tag; SCR Engineers, Ltd; Netanya, Israel), which logged daily rumination and general activity. Skeletal growth variables were assessed by measuring wither and hip height pretrial and posttrial. Ultrasonography provided additional resolution concerning growing phase compositional gain, which was later verified by carcass data collection. Data were analyzed as a nested analysis of variance with BW and gender serving as blocking factors. The increased caloric density of the diets administered to MEC and AGR calves resulted in greater average daily gain and gain:feed values compared with CON even during the first 21 d of diet acclimation ( ≤ 0.05). Additional fiber concentration of CON diets led to increased rumination times in 9 of the 10 wk of trial ( ≤ 0.10). No differences amongst treatments were detected for skeletal variables or ultrasound 12th rib fat. Cattle fed CON diets posted 3.4% inferior BW at the end of the growing period trial and a 3.8% reduction in hot carcass weight (HCW), reinforcing the theory that intensifying caloric intake during the growing phase does not compromise future feedlot performance. Ultrasound marbling scores for MEC-treated cattle were 19° greater than AGR treated cattle ( ≤ 0.05) at the end of the growing phase trial. Nearly the exact same advantage (22°) was observed in the cooler 5 mo later ( = 0.42). Implying MEC metabolically imprinted cattle to favor marbling development. It appears that maximizing dietary caloric density in light-weight calves does not adversely affect the growth curve, while oral dosing of MEC during the growing period may be a precursor for enhanced quality grade.
PubMed: 32705029
DOI: 10.1093/tas/txaa031 -
Frontiers in Microbiology 2019is an ecologically important rumen bacterium that metabolizes lactate and relieves rumen acidosis (RA) induced by a high-grain-diet. Understanding the regulatory...
is an ecologically important rumen bacterium that metabolizes lactate and relieves rumen acidosis (RA) induced by a high-grain-diet. Understanding the regulatory mechanisms of the lactate metabolism of this species in RA conditions might contribute to developing dietary strategies to alleviate RA. was co-cultured with four lactate producers (, , , and ) and a series of substrate starch doses (1, 3, and 9 g/L) were used to induce one normal and two RA models (subacute rumen acidosis, SARA and acute rumen acidosis, ARA) under batch conditions. The associations between bacterial competition and the shift of organic acids' (OA) accumulation patterns in both statics and dynamics manners were investigated in RA models. Furthermore, we examined the effects of substrate lactate concentration and pH on lactate degradation pattern and genes related to the lactate utilizing pathways in the continuous culture. The positive growth of and caused OA accumulation in the SARA model to shift from lactate to butyrate and resulted in pH recovery. Furthermore, both the quantities of substrate lactate and pH had remarkable effects on lactate utilization due to the transcriptional regulation of metabolic genes, and the lactate utilization in was more sensitive to pH changes than to the substrate lactate level. In addition, compared with associations based on statics data, associations discovered from dynamics data showed greater significance and gave additional explanations regarding the relationships between bacterial competition and OA accumulation.
PubMed: 30792704
DOI: 10.3389/fmicb.2019.00162 -
Animal Microbiome Oct 2021The gut microbiota influences host performance playing a relevant role in homeostasis and function of the immune system. The aim of the present work was to identify...
BACKGROUND
The gut microbiota influences host performance playing a relevant role in homeostasis and function of the immune system. The aim of the present work was to identify microbial signatures linked to immunity traits and to characterize the contribution of host-genome and gut microbiota to the immunocompetence in healthy pigs.
RESULTS
To achieve this goal, we undertook a combination of network, mixed model and microbial-wide association studies (MWAS) for 21 immunity traits and the relative abundance of gut bacterial communities in 389 pigs genotyped for 70K SNPs. The heritability (h; proportion of phenotypic variance explained by the host genetics) and microbiability (m; proportion of variance explained by the microbial composition) showed similar values for most of the analyzed immunity traits, except for both IgM and IgG in plasma that was dominated by the host genetics, and the haptoglobin in serum which was the trait with larger m (0.275) compared to h (0.138). Results from the MWAS suggested a polymicrobial nature of the immunocompetence in pigs and revealed associations between pigs gut microbiota composition and 15 of the analyzed traits. The lymphocytes phagocytic capacity (quantified as mean fluorescence) and the total number of monocytes in blood were the traits associated with the largest number of taxa (6 taxa). Among the associations identified by MWAS, 30% were confirmed by an information theory network approach. The strongest confirmed associations were between Fibrobacter and phagocytic capacity of lymphocytes (r = 0.37), followed by correlations between Streptococcus and the percentage of phagocytic lymphocytes (r = -0.34) and between Megasphaera and serum concentration of haptoglobin (r = 0.26). In the interaction network, Streptococcus and percentage of phagocytic lymphocytes were the keystone bacterial and immune-trait, respectively.
CONCLUSIONS
Overall, our findings reveal an important connection between gut microbiota composition and immunity traits in pigs, and highlight the need to consider both sources of information, host genome and microbial levels, to accurately characterize immunocompetence in pigs.
PubMed: 34689834
DOI: 10.1186/s42523-021-00138-9 -
Clinical and Experimental Dental... Feb 2022It has been suggested that smoking affects the oral microbiome, but its effects on sites other than the subgingival microbiome remain unclear. This study investigated...
OBJECTIVES
It has been suggested that smoking affects the oral microbiome, but its effects on sites other than the subgingival microbiome remain unclear. This study investigated the composition of the salivary and tongue bacterial communities of smokers and nonsmokers in periodontally healthy adults.
METHODS
The study population included 50 healthy adults. The bacterial composition of resting saliva and the tongue coating was identified through barcoded pyrosequencing analysis of the 16S rRNA gene. The Brinkman index (BI) was used to calculate lifetime exposure to smoking. The richness and diversity of the microbiome were evaluated using the t-test. Differences in the proportions of bacterial genera between smokers and nonsmokers were evaluated using the Mann-Whitney U test. The quantitative relationship between the proportions of genera and the BI was evaluated using Pearson's correlation analysis.
RESULTS
The richness and diversity of the oral microbiome differed significantly between saliva and the tongue but not between smokers and nonsmokers. The saliva samples from smokers were enriched with the genera Treponema and Selenomonas. The tongue samples from smokers were enriched with the genera Dialister and Atopobium. The genus Cardiobacterium in saliva, and the genus Granulicatella on the tongue, were negatively correlated with BI values. On the other hand, the genera Treponema, Oribacterium, Dialister, Filifactor, Veillonella, and Selenomonas in saliva and Dialister, Bifidobacterium, Megasphaera, Mitsuokella, and Cryptobacterium on the tongue were positively correlated with BI values.
CONCLUSIONS
The saliva and tongue microbial profiles of smokers and nonsmokers differed in periodontally healthy adults. The genera associated with periodontitis and oral malodor accounted for high proportions in saliva and on the tongue of smokers without periodontitis and were positively correlated with lifetime exposure to smoking. The tongue might be a reservoir of pathogens associated with oral disease in smokers.
Topics: Adult; Bacteria; Cigarette Smoking; Humans; Microbiota; Periodontitis; RNA, Ribosomal, 16S; Tongue
PubMed: 34505401
DOI: 10.1002/cre2.489 -
Bioengineering (Basel, Switzerland) Aug 2022Recent studies have revealed that LuxS/AI-2 quorum sensing (QS) is the most universal cell-to-cell communication in rumen bacteria; however, it remains unknown how they...
Recent studies have revealed that LuxS/AI-2 quorum sensing (QS) is the most universal cell-to-cell communication in rumen bacteria; however, it remains unknown how they respond to nutritional stress from a diet shift. This study aimed to explore whether a diet shift could trigger rumen bacterial LuxS/AI-2 QS and its influences on rumen fermentation characteristics and bacterial community diversity and composition. A total of fifteen Hu sheep were selected to undergo a pre-shift diet (Pre, concentrate to forage ratio 75:25) for one month and then abruptly switch to a post-shift diet (Post, concentrate to forage ratio 49:51). Results showed that the serum cortisol and immunoglobulin G concentrations were higher in Post than in Pre (p < 0.05). The microbial density, AI-2 concentration, biofilm formation, and the gene expression of ftsH were higher in Post when compared with Pre (p < 0.05), whilst the gene expression of luxS tended to be lower in Post (p = 0.054). The molar concentration of valerate and fermentation efficiency decreased after the diet shift, while the acetate to propionate ratio and the molar proportion of butyrate were higher in Post compared to Pre (p < 0.05). Moreover, the diet shift increased the richness of ruminal bacteria and the relative abundances of Roseburia, Prevotellaceae UCG-001, and Lachnospira, and decreased the relative abundances of Prevotella, Megasphaera, and Dialister (p < 0.05). A difference in trends was also observed in an analysis of similarity (R = 0.1208 and p = 0.064). This study suggests that a diet shift could trigger rumen bacterial LuxS/AI-2 QS by altering microbial density, AI-2 concentration, biofilm formation, and related gene expression, as well as affect the rumen fermentation pattern and bacterial community diversity and composition. This study may provide insight into a potential strategy for relieving nutritional stress via regulating bacterial communication.
PubMed: 36004904
DOI: 10.3390/bioengineering9080379 -
Gut-microbiome-based predictive model for ST-elevation myocardial infarction in young male patients.Frontiers in Microbiology 2022ST-segment elevation myocardial infarction (STEMI) in young male patients accounts for a significant proportion of total heart attack events. Therefore, clinical...
BACKGROUND
ST-segment elevation myocardial infarction (STEMI) in young male patients accounts for a significant proportion of total heart attack events. Therefore, clinical awareness and screening for acute myocardial infarction (AMI) in asymptomatic patients at a young age is required. The gut microbiome is potentially involved in the pathogenesis of STEMI. The aim of the current study is to develop an early risk prediction model based on the gut microbiome and clinical parameters for this population.
METHODS
A total of 81 young males (age < 44 years) were enrolled in this study. Forty-one young males with STEMI were included in the case group, and the control group included 40 young non-coronary artery disease (CAD) males. To identify the differences in gut microbiome markers between these two groups, 16S rRNA-based gut microbiome sequencing was performed using the Illumina MiSeq platform. Further, a nomogram and corresponding web page were constructed. The diagnostic efficacy and practicability of the model were analyzed using K-fold cross-validation, calibration curves, and decision curve analysis (DCA).
RESULTS
Compared to the control group, a significant decrease in tendency regarding α and β diversity was observed in patients in the case group and identified as a significantly altered gut microbiome represented by and . Regarding clinical parameters, compared to the control group, the patients in the case group had a higher body mass index (BMI), systolic blood pressure (SBP), triglyceride (TG), alanine aminotransferase (ALT), and aspartate aminotransferase (AST) and low blood urea nitrogen (BUN). Additionally, BMI and SBP were significantly (p<0.05) positively correlated with and . Further, BMI and SBP were significantly (p<0.05) negatively correlated with and . A significant negative correlation was only observed between and AST ( < 0.05). Finally, an early predictive nomogram and corresponding web page were constructed based on the gut microbiome and clinical parameters with an area under the receiver-operating characteristic (ROC) curve (AUC) of 0.877 and a C-index of 0.911. For the internal validation, the stratified -fold cross-validation ( = 3) was as follows: AUC value of 0.934. The calibration curves of the model showed good consistency between the actual and predicted probabilities. The DCA results showed that the model had a high net clinical benefit for use in the clinical setting.
CONCLUSION
In this study, we combined the gut microbiome and common clinical parameters to construct a prediction model. Our analysis shows that the constructed model is a non-invasive tool with potential clinical application in predicting STEMI in the young males.
PubMed: 36532426
DOI: 10.3389/fmicb.2022.1031878 -
American Journal of Obstetrics and... Jun 2018Data evaluating the impact of contraceptives on the vaginal microbiome are limited and inconsistent.
BACKGROUND
Data evaluating the impact of contraceptives on the vaginal microbiome are limited and inconsistent.
OBJECTIVE
We hypothesized that women initiating copper intrauterine device use would have increased bacterial vaginosis and bacterial vaginosis-associated microbes with use compared to women initiating and using hormonal contraceptive methods.
STUDY DESIGN
Vaginal swabs (N = 1047 from 266 participants seeking contraception) for Nugent score determination of bacterial vaginosis and quantitative polymerase chain reaction analyses for assessment of specific microbiota were collected from asymptomatic, healthy women aged 18-35 years in Harare, Zimbabwe, who were confirmed to be free of nonstudy hormones by mass spectrometry at each visit. Contraception was initiated with an injectable (depot medroxyprogesterone acetate [n = 41], norethisterone enanthate [n = 44], or medroxyprogesterone acetate and ethinyl estradiol [n = 40]), implant (levonorgestrel [n = 45] or etonogestrel [n = 48]), or copper intrauterine device (n = 48) and repeat vaginal swabs were collected after 30, 90, and 180 days of continuous use. Self-reported condom use was similar across all arms at baseline. Quantitative polymerase chain reaction was used to detect Lactobacillus crispatus, L jensenii, L gasseri/johnsonii group, L vaginalis, L iners, Gardnerella vaginalis, Atopobium vaginae, and Megasphaera-like bacterium phylotype I from swabs. Modified Poisson regression and mixed effects linear models were used to compare marginal prevalence and mean difference in quantity (expressed as gene copies/swab) prior to and during contraceptive use.
RESULTS
Bacterial vaginosis prevalence increased in women initiating copper intrauterine devices from 27% at baseline, 35% at 30 days, 40% at 90 days, and 49% at 180 days (P = .005 compared to marginal prevalence at enrollment). Women initiating hormonal methods had no change in bacterial vaginosis prevalence over 180 days. The mean increase in Nugent score was 1.2 (95% confidence interval, 0.5-2.0; P = .001) in women using copper intrauterine devices. Although the frequency and density of beneficial lactobacilli did not change among intrauterine device users over 6 months, there was an increase in the log concentration of G vaginalis (4.7, 5.2, 5.8, 5.9; P = .046) and A vaginae (3.0, 3.8, 4.6, 5.1; P = .002) between baseline and 30, 90, and 180 days after initiation. Among other contraceptive groups, women using depot medroxyprogesterone acetate had decreased L iners (mean decrease log concentration = 0.8; 95% confidence interval, 0.3-1.5; P = .004) and there were no significant changes in beneficial Lactobacillus species over 180 days regardless of contraceptive method used.
CONCLUSION
Copper intrauterine device use may increase colonization by bacterial vaginosis-associated microbiota, resulting in increased prevalence of bacterial vaginosis. Use of most hormonal contraception does not alter vaginal microbiota.
Topics: Adult; Contraceptive Agents, Female; DNA, Bacterial; Desogestrel; Drug Implants; Ethinyl Estradiol; Female; Gardnerella vaginalis; Humans; Intrauterine Devices, Copper; Lactobacillus crispatus; Lactobacillus gasseri; Levonorgestrel; Medroxyprogesterone Acetate; Megasphaera; Microbiota; Norethindrone; Polymerase Chain Reaction; Protective Factors; Risk Factors; Vagina; Vaginosis, Bacterial; Young Adult
PubMed: 29505773
DOI: 10.1016/j.ajog.2018.02.017 -
Microbial Genomics Dec 2021The composition of the human vaginal microbiome has been extensively studied and is known to influence reproductive health. However, the functional roles of individual...
The composition of the human vaginal microbiome has been extensively studied and is known to influence reproductive health. However, the functional roles of individual taxa and their contributions to negative health outcomes have yet to be well characterized. Here, we examine two vaginal bacterial taxa grouped within the genus that have been previously associated with bacterial vaginosis (BV) and pregnancy complications. Phylogenetic analyses support the classification of these taxa as two distinct species. These two phylotypes, phylotype 1 (MP1) and phylotype 2 (MP2), differ in genomic structure and metabolic potential, suggestive of differential roles within the vaginal environment. Further, these vaginal taxa show evidence of genome reduction and changes in DNA base composition, which may be common features of host dependence and/or adaptation to the vaginal environment. In a cohort of 3870 women, we observed that MP1 has a stronger positive association with bacterial vaginosis whereas MP2 was positively associated with trichomoniasis. MP1, in contrast to MP2 and other common BV-associated organisms, was not significantly excluded in pregnancy. In a cohort of 52 pregnant women, MP1 was both present and transcriptionally active in 75.4 % of vaginal samples. Conversely, MP2 was largely absent in the pregnant cohort. This study provides insight into the evolutionary history, genomic potential and predicted functional role of two clinically relevant vaginal microbial taxa.
Topics: Bacterial Proteins; Base Composition; Case-Control Studies; Evolution, Molecular; Female; Gene Expression Regulation, Bacterial; Genome Size; Genome, Bacterial; High-Throughput Nucleotide Sequencing; Humans; Megasphaera; Phylogeny; Pregnancy; RNA, Ribosomal, 16S; Reproductive Health; Sequence Analysis, DNA; Vagina; Vaginosis, Bacterial
PubMed: 34898422
DOI: 10.1099/mgen.0.000526