Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 2.453
Filtrar
1.
Microbiome ; 9(1): 180, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34470652

RESUMO

BACKGROUND: Probiotics have been used to regulate the gut microbiota and physiology in various contexts, but their precise mechanisms of action remain unclear. RESULTS: By population genomic analysis of 418 Bifidobacterium longum strains, including 143 newly sequenced in this study, three geographically distinct gene pools/populations, BLAsia1, BLAsia2, and BLothers, were identified. Genes involved in cell wall biosynthesis, particularly peptidoglycan biosynthesis, varied considerably among the core genomes of the different populations, but accessory genes that contributed to the carbohydrate metabolism were significantly distinct. Although active transmission was observed inter-host, inter-country, inter-city, intra-community, and intra-family, a single B. longum clone seemed to reside within each individual. A significant negative association was observed between host age and relative abundance of B. longum, while there was a strong positive association between host age and strain genotype [e.g., single nucleotide polymorphisms in the arginine biosynthesis pathway]. Further animal experiments performed with the B. longum isolates via using a D-galactose-induced aging mouse model supported these associations, in which B. longum strains with different genotypes in arginine biosynthesis pathway showed divergent abilities on protecting against host aging possibly via their different abilities to modify the metabolism of gut microbes. CONCLUSIONS: This is the first known example of research on the evolutionary history and transmission of this probiotic species. Our results propose a new mechanistic insight for promoting host longevity via the informed use of specific probiotics or molecules. Video abstract.


Assuntos
Bifidobacterium longum , Microbioma Gastrointestinal , Probióticos , Sulfaleno , Envelhecimento , Animais , Galactose , Microbioma Gastrointestinal/genética , Humanos , Camundongos
2.
Microbiome ; 9(1): 183, 2021 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-34493329

RESUMO

BACKGROUND: P-glycoprotein (P-gp) plays a critical role in protection of the intestinal epithelia by mediating efflux of drugs/xenobiotics from the intestinal mucosa into the gut lumen. Recent studies bring to light that P-gp also confers a critical link in communication between intestinal mucosal barrier function and the innate immune system. Yet, despite knowledge for over 10 years that P-gp plays a central role in gastrointestinal homeostasis, the precise molecular mechanism that controls its functional expression and regulation remains unclear. Here, we assessed how the intestinal microbiome drives P-gp expression and function. RESULTS: We have identified a "functional core" microbiome of the intestinal gut community, specifically genera within the Clostridia and Bacilli classes, that is necessary and sufficient for P-gp induction in the intestinal epithelium in mouse models. Metagenomic analysis of this core microbial community revealed that short-chain fatty acid and secondary bile acid production positively associate with P-gp expression. We have further shown these two classes of microbiota-derived metabolites synergistically upregulate P-gp expression and function in vitro and in vivo. Moreover, in patients suffering from ulcerative colitis (UC), we find diminished P-gp expression coupled to the reduction of epithelial-derived anti-inflammatory endocannabinoids and luminal content (e.g., microbes or their metabolites) with a reduced capability to induce P-gp expression. CONCLUSION: Overall, by means of both in vitro and in vivo studies as well as human subject sample analysis, we identify a mechanistic link between cooperative functional outputs of the complex microbial community and modulation of P-gp, an epithelial component, that functions to suppress overactive inflammation to maintain intestinal homeostasis. Hence, our data support a new cross-talk paradigm in microbiome regulation of mucosal inflammation. Video abstract.


Assuntos
Microbioma Gastrointestinal , Subfamília B de Transportador de Cassetes de Ligação de ATP , Membro 1 da Subfamília B de Cassetes de Ligação de ATP , Animais , Microbioma Gastrointestinal/genética , Homeostase , Humanos , Mucosa Intestinal , Camundongos
4.
Nat Commun ; 12(1): 4907, 2021 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-34389726

RESUMO

The intestinal mucosa constitutes an environment of closely regulated immune cells. Dendritic cells (DC) interact with the gut microbiome and antigens and are important in maintaining gut homeostasis. Here, we investigate DC transcriptome, phenotype and function in five anatomical locations of the gut lamina propria (LP) which constitute different antigenic environments. We show that DC from distinct gut LP compartments induce distinct T cell differentiation and cytokine secretion. We also find that PD-L1+ DC in the duodenal LP and XCR1+ DC in the colonic LP comprise distinct tolerogenic DC subsets that are crucial for gut homeostasis. Mice lacking PD-L1+ and XCR1+ DC have a proinflammatory gut milieu associated with an increase in Th1/Th17 cells and a decrease in Treg cells and have exacerbated disease in the models of 5-FU-induced mucositis and DSS-induced colitis. Our findings identify PD-L1+ and XCR1+ DC as region-specific physiologic regulators of intestinal homeostasis.


Assuntos
Antígeno B7-H1/imunologia , Células Dendríticas/imunologia , Homeostase/imunologia , Mucosa Intestinal/imunologia , Receptores de Quimiocinas/imunologia , Animais , Antígeno B7-H1/genética , Antígeno B7-H1/metabolismo , Colite/genética , Colite/imunologia , Colite/metabolismo , Citocinas/imunologia , Citocinas/metabolismo , Células Dendríticas/metabolismo , Fezes/microbiologia , Feminino , Microbioma Gastrointestinal/genética , Microbioma Gastrointestinal/imunologia , Homeostase/genética , Humanos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Receptores de Quimiocinas/genética , Receptores de Quimiocinas/metabolismo , Linfócitos T/citologia , Linfócitos T/imunologia , Linfócitos T/metabolismo , Transcriptoma/genética , Transcriptoma/imunologia
5.
Nat Commun ; 12(1): 4728, 2021 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-34354065

RESUMO

Understanding how diet and gut microbiota interact in the context of human health is a key question in personalized nutrition. Genome-scale metabolic networks and constraint-based modeling approaches are promising to systematically address this complex problem. However, when applied to nutritional questions, a major issue in existing reconstructions is the limited information about compounds in the diet that are metabolized by the gut microbiota. Here, we present AGREDA, an extended reconstruction of diet metabolism in the human gut microbiota. AGREDA adds the degradation pathways of 209 compounds present in the human diet, mainly phenolic compounds, a family of metabolites highly relevant for human health and nutrition. We show that AGREDA outperforms existing reconstructions in predicting diet-specific output metabolites from the gut microbiota. Using 16S rRNA gene sequencing data of faecal samples from Spanish children representing different clinical conditions, we illustrate the potential of AGREDA to establish relevant metabolic interactions between diet and gut microbiota.


Assuntos
Dieta , Microbioma Gastrointestinal/fisiologia , Redes e Vias Metabólicas , Modelos Biológicos , Algoritmos , Criança , Fenômenos Fisiológicos da Nutrição Infantil , Dieta Mediterrânea , Fermentação , Microbioma Gastrointestinal/genética , Humanos , Técnicas In Vitro , Lens (Planta)/química , Valor Nutritivo , RNA Ribossômico 16S/genética , Espanha
6.
Microbiome ; 9(1): 167, 2021 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-34362459

RESUMO

BACKGROUND: The gut microbiome changes in response to a range of environmental conditions, life events and disease states. Pregnancy is a natural life event that involves major physiological adaptation yet studies of the microbiome in pregnancy are limited and their findings inconsistent. Pregnancy with type 1 diabetes (T1D) is associated with increased maternal and fetal risks but the gut microbiome in this context has not been characterized. By whole metagenome sequencing (WMS), we defined the taxonomic composition and function of the gut bacterial microbiome across 70 pregnancies, 36 in women with T1D. RESULTS: Women with and without T1D exhibited compositional and functional changes in the gut microbiome across pregnancy. Profiles in women with T1D were distinct, with an increase in bacteria that produce lipopolysaccharides and a decrease in those that produce short-chain fatty acids, especially in the third trimester. In addition, women with T1D had elevated concentrations of fecal calprotectin, a marker of intestinal inflammation, and serum intestinal fatty acid-binding protein (I-FABP), a marker of intestinal epithelial damage. CONCLUSIONS: Women with T1D exhibit a shift towards a more pro-inflammatory gut microbiome during pregnancy, associated with evidence of intestinal inflammation. These changes could contribute to the increased risk of pregnancy complications in women with T1D and are potentially modifiable by dietary means. Video abstract.


Assuntos
Diabetes Mellitus Tipo 1 , Microbioma Gastrointestinal , Fezes , Feminino , Microbioma Gastrointestinal/genética , Humanos , Intestinos , Metagenoma , Gravidez
7.
J Insect Sci ; 21(4)2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34415303

RESUMO

The gut microbiota of insects usually plays an important role in the development and reproduction of their hosts. The fecundity of Henosepilachna vigintioctopunctata (Fabricius) varies greatly when they develop on different host plants. Whether and how the gut microbiota regulates the fecundity of H. vigintioctopunctata was unknown. To address this question, we used 16S rRNA sequencing to analyze the gut microbiomes of H. vigintioctopunctata adults fed on two host plant species (Solanum nigrum and Solanum melongena) and one artificial diet. The development of the ovaries and testes was also examined. Our results revealed that the diversity and abundance of gut microorganisms varied significantly in insects reared on different diets. The gut microbiota of H. vigintioctopunctata raised on the two host plants was similar, with Proteobacteria being the dominant phylum in both groups, whereas Firmicutes was the dominant phylum in the group reared on the artificial diet. The predominant microbiota in the S. nigrum group were Acinetobacter soli and Acinetobacter ursingii (Acinetobacter, Moraxellaceae); Moraxella osloensis (Enhydrobacter, Moraxellaceae); and Empedobacter brevis (Empedobacter, Weeksellaceae). The microbiota in this group are associated with high lipid metabolism. In addition, the beetles' ovaries and testes were more highly developed in the S. nigrum group than in the other two groups. These findings provide valuable information for elucidating the complex roles the gut microbiota play in the fecundity of H. vigintioctopunctata, and may also contribute to developing future novel control strategies involving this economically important pest.


Assuntos
Besouros , Fertilidade , Microbioma Gastrointestinal/genética , Animais , Bactérias/isolamento & purificação , Besouros/microbiologia , Besouros/fisiologia , DNA Bacteriano , Dieta , Feminino , Metabolismo dos Lipídeos , Masculino , Metagenômica , Ovário/crescimento & desenvolvimento , Controle de Pragas , RNA Ribossômico 16S , Testículo/crescimento & desenvolvimento
8.
FASEB J ; 35(9): e21783, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34403510

RESUMO

Melatonin is a pleiotropic molecule with a variety of biological functions, which include its immunoregulatory action in mammals. Brucellosis is a worldwide endemic zoonotic disease caused by the Brucella, which not only causes huge economic losses for the livestock industry but also impacts human health. To target this problem, in current study, two marker-free transgenic sheep overexpressing melatonin synthetic enzyme ASMT (acetylserotonin O-methyltransferase) gene were generated and these melatonin enrich transgenic sheep were challenged by Brucella infection. The results showed that the serum melatonin concentration was significantly higher in transgenic sheep than that of wild type (726.92 ± 70.6074 vs 263.10 ± 34.60 pg/mL, P < .05). Brucella challenge test showed that two thirds (4/6) of the wild-type sheep had brucellosis, while none of the transgenic sheep were infected. Whole-blood RNA-seq results showed that differential expression genes (DEGs) were significantly enriched in natural killer cell-mediated cytotoxicity, phagosome, antigen processing, and presentation signaling pathways in overexpression sheep. The DEGs of toll-like receptors (TLRs) and NOD-like receptors (NLRs) families were verified by qPCR and it showed that TLR1, TLR2, TLR7, CD14, NAIP, and CXCL8 expression levels in overexpression sheep were significantly higher and NLRP1, NLRP3, and TNF expression levels were significantly lower than those of wild type. The rectal feces were subjected to 16S rDNA amplicon sequencing, and the microbial functional analysis showed that the transgenic sheep had significantly lower abundance of microbial genes related to infectious diseases compared to the wild type, indicating overexpression animals are likely more resistant to infectious diseases than wild type. Furthermore, exogenous melatonin treatment relieved brucellosis inflammation by upregulating anti-inflammatory cytokines IL-4 and downregulating pro-inflammatory IL-2, IL-6, and IFN-γ. Our preliminary results provide an informative reference for the study of the relationship between melatonin and brucellosis.


Assuntos
Acetilserotonina O-Metiltransferasa/genética , Brucelose/genética , Brucelose/imunologia , Microbioma Gastrointestinal , Transdução de Sinais/imunologia , Acetilserotonina O-Metiltransferasa/metabolismo , Animais , Animais Geneticamente Modificados , Brucelose/prevenção & controle , Fezes/microbiologia , Microbioma Gastrointestinal/genética , Mediadores da Inflamação/imunologia , Melatonina/uso terapêutico , Ovinos/imunologia
9.
Science ; 373(6551): 181-186, 2021 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-34244407

RESUMO

Relatives have more similar gut microbiomes than nonrelatives, but the degree to which this similarity results from shared genotypes versus shared environments has been controversial. Here, we leveraged 16,234 gut microbiome profiles, collected over 14 years from 585 wild baboons, to reveal that host genetic effects on the gut microbiome are nearly universal. Controlling for diet, age, and socioecological variation, 97% of microbiome phenotypes were significantly heritable, including several reported as heritable in humans. Heritability was typically low (mean = 0.068) but was systematically greater in the dry season, with low diet diversity, and in older hosts. We show that longitudinal profiles and large sample sizes are crucial to quantifying microbiome heritability, and indicate scope for selection on microbiome characteristics as a host phenotype.


Assuntos
Bactérias/classificação , Meio Ambiente , Microbioma Gastrointestinal/genética , Papio/microbiologia , Actinobacteria/classificação , Actinobacteria/genética , Actinobacteria/crescimento & desenvolvimento , Actinobacteria/isolamento & purificação , Envelhecimento , Animais , Bactérias/genética , Bactérias/crescimento & desenvolvimento , Bactérias/isolamento & purificação , Bacteroidetes/classificação , Bacteroidetes/genética , Bacteroidetes/crescimento & desenvolvimento , Bacteroidetes/isolamento & purificação , Dieta , Fezes/microbiologia , Feminino , Firmicutes/classificação , Firmicutes/genética , Firmicutes/crescimento & desenvolvimento , Firmicutes/isolamento & purificação , Genótipo , Humanos , Masculino , Papio/genética , Fenótipo , Estações do Ano , Comportamento Social
10.
J Affect Disord ; 293: 363-372, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34233229

RESUMO

BACKGROUND: Animal and human studies have revealed reciprocal association between exercise and gut-brain axis. However, the clinical evidence from randomized controlled trials (RCT) are still limited to directly assess the effects of aerobic exercise on gut microbiota. To fill this gap, we conducted this 12-week RCT in both groups of adolescents with and without sub-threshold mood symptoms. METHODS: A total of 224 adolescents were randomized to the aerobic exercise intervention or psychoeducation-controlled arm. 49 adolescents with subthreshold symptoms and 142 clinically-well adolescents provided the sample for microbiota assessed by metagenomic sequencing. Aerobic exercise of running at the moderate-intensity for 30 min per day, 5 days a week, were conducted for 12 weeks. RESULTS: Adolescents with subthreshold symptoms had significantly lower beta diversity than clinically-well adolescents in both the exercise intervention and psychoeducation-controlled arms (p<0.05). After intervention, no difference in gut microbiota diversity, phylum, genus, species level abundancies or gut microbial functions were found in both of the symptomatic or non-symptomatic groups. Metagenome-wide association study analysis showed no significant difference in metagenomic linkage groups. LIMITATIONS: The sample size is relatively small. The exercise intensity we employed may be insufficient to result in observable effects on intestinal microbiota. CONCLUSION: We conclude that a 12-week moderate-intensity aerobic exercise intervention showed no significant beneficial effect on the gut microbiota in clinically-well adolescents as well as in adolescents with subthreshold symptoms. The beta diversity of gut microbiota in adolescents with subthreshold mood syndromes may be impaired when compared with clinically-well adolescents.


Assuntos
Microbioma Gastrointestinal , Microbiota , Adolescente , Afeto , Animais , Exercício Físico , Microbioma Gastrointestinal/genética , Humanos , Síndrome
11.
Nat Commun ; 12(1): 4188, 2021 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-34234121

RESUMO

Klebsiella pneumoniae is a leading cause of antimicrobial-resistant (AMR) healthcare-associated infections, neonatal sepsis and community-acquired liver abscess, and is associated with chronic intestinal diseases. Its diversity and complex population structure pose challenges for analysis and interpretation of K. pneumoniae genome data. Here we introduce Kleborate, a tool for analysing genomes of K. pneumoniae and its associated species complex, which consolidates interrogation of key features of proven clinical importance. Kleborate provides a framework to support genomic surveillance and epidemiology in research, clinical and public health settings. To demonstrate its utility we apply Kleborate to analyse publicly available Klebsiella genomes, including clinical isolates from a pan-European study of carbapenemase-producing Klebsiella, highlighting global trends in AMR and virulence as examples of what could be achieved by applying this genomic framework within more systematic genomic surveillance efforts. We also demonstrate the application of Kleborate to detect and type K. pneumoniae from gut metagenomes.


Assuntos
Proteínas de Bactérias/genética , Infecção Hospitalar/microbiologia , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/genética , Tipagem Molecular/métodos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Infecção Hospitalar/diagnóstico , Infecção Hospitalar/tratamento farmacológico , Infecção Hospitalar/epidemiologia , Conjuntos de Dados como Assunto , Farmacorresistência Bacteriana Múltipla/genética , Monitoramento Epidemiológico , Microbioma Gastrointestinal/genética , Genoma Bacteriano , Humanos , Lactente , Recém-Nascido , Infecções por Klebsiella/diagnóstico , Infecções por Klebsiella/tratamento farmacológico , Infecções por Klebsiella/epidemiologia , Klebsiella pneumoniae/isolamento & purificação , Klebsiella pneumoniae/patogenicidade , Metagenoma/genética , Epidemiologia Molecular/métodos , Mutação , Filogenia , Software , Virulência/genética , Fatores de Virulência/genética , Sequenciamento Completo do Genoma , beta-Lactamases/genética
12.
Int J Mol Sci ; 22(13)2021 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-34203536

RESUMO

Primary sclerosing cholangitis (PSC) is an immune-related cholangiopathy characterized by biliary inflammation, cholestasis, and multifocal bile duct strictures. It is associated with high rates of progression to end-stage liver disease as well as a significant risk of cholangiocarcinoma (CCA), gallbladder cancer, and colorectal carcinoma. Currently, no effective medical treatment with an impact on the overall survival is available, and liver transplantation is the only curative treatment option. Emerging evidence indicates that gut microbiota is associated with disease pathogenesis. Several studies analyzing fecal and mucosal samples demonstrate a distinct gut microbiome in individuals with PSC compared to healthy controls and individuals with inflammatory bowel disease (IBD) without PSC. Experimental mouse and observational human data suggest that a diverse set of microbial functions may be relevant, including microbial metabolites and bacterial processing of pharmacological agents, bile acids, or dietary compounds, altogether driving the intrahepatic inflammation. Despite critical progress in this field over the past years, further functional characterization of the role of the microbiota in PSC and related malignancies is needed. In this review, we discuss the available data on the role of the gut microbiome and elucidate important insights into underlying pathogenic mechanisms and possible microbe-altering interventions.


Assuntos
Neoplasias dos Ductos Biliares/metabolismo , Colangite Esclerosante/metabolismo , Microbioma Gastrointestinal/fisiologia , Animais , Neoplasias dos Ductos Biliares/genética , Colangiocarcinoma/genética , Colangiocarcinoma/metabolismo , Colangite Esclerosante/genética , Microbioma Gastrointestinal/genética , Humanos , Doenças Inflamatórias Intestinais/genética , Doenças Inflamatórias Intestinais/metabolismo , Camundongos
13.
Front Cell Infect Microbiol ; 11: 636808, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34249773

RESUMO

The frequency of azoxymethane/dextran sulfate sodium (AOM/DSS)-induced carcinogenesis in male mice is higher than that in female mice. Previous studies have reported that 17ß-estradiol inhibits tumorigenesis in males by modulating nuclear factor-erythroid 2-related factor 2 (Nrf2). This study aimed to investigate the changes in mouse gut microbiome composition based on sex, AOM/DSS-induced colorectal cancer (CRC), and Nrf2 genotype. The gut microbiome composition was determined by 16S rRNA gene sequencing fecal samples obtained at week 16 post-AOM administration. In terms of sex differences, our results showed that the wild-type (WT) male control mice had higher alpha diversity (i.e. Chao1, Shannon, and Simpson) than the WT female control mice. The linear discriminant analysis effect size (LEfSe) results revealed that the abundances of Akkermansia muciniphila and Lactobacillus murinus were higher in WT male control mice than in WT female controls. In terms of colon tumorigenesis, the alpha diversity of the male CRC group was lower than that of the male controls in both WT and Nrf2 KO, but did not show such changes in females. Furthermore, the abundance of A. muciniphila was higher in male CRC groups than in male controls in both WT and Nrf2 KO. The abundance of Bacteroides vulgatus was higher in WT CRC groups than in WT controls in both males and females. However, the abundance of L. murinus was lower in WT female CRC and Nrf2 KO male CRC groups than in its controls. The abundance of A. muciniphila was not altered by Nrf2 KO. In contrast, the abundances of L. murinus and B. vulgatus were changed differently by Nrf2 KO depending on sex and CRC. Interestingly, L. murinus showed negative correlation with tumor numbers in the whole colon. In addition, B. vulgatus showed positive correlation with inflammatory markers (i.e. myeloperoxidase and IL-1ß levels), tumor numbers, and high-grade adenoma, especially, developed mucosal and submucosal invasive adenocarcinoma at the distal part of the colon. In conclusion, Nrf2 differentially alters the gut microbiota composition depending on sex and CRC induction.


Assuntos
Neoplasias do Colo , Neoplasias Colorretais , Microbioma Gastrointestinal , Animais , Bacteroides , Colo , Sulfato de Dextrana , Modelos Animais de Doenças , Feminino , Microbioma Gastrointestinal/genética , Lactobacillus , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fator 2 Relacionado a NF-E2/genética , RNA Ribossômico 16S/genética
14.
Int J Mol Sci ; 22(11)2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34205981

RESUMO

Dietary changes are known to alter the composition of the gut microbiome. However, it is less understood how repeatable and reversible these changes are and how diet switches affect the microbiota in the various segments of the gastrointestinal tract. Here, a treatment group of conventionally raised laboratory mice is subjected to two periods of western diet (WD) interrupted by a period of standard diet (SD) of the same duration. Beta-diversity analyses show that diet-induced microbiota changes are largely reversible (q = 0.1501; PERMANOVA, weighted-UniFrac comparison of the treatment-SD group to the control-SD group) and repeatable (q = 0.032; PERMANOVA, weighted-UniFrac comparison of both WD treatments). Furthermore, we report that diet switches alter the gut microbiota composition along the length of the intestinal tract in a segment-specific manner, leading to gut segment-specific Firmicutes/Bacteroidota ratios. We identified prevalent and distinct Amplicon Sequencing Variants (ASVs), particularly in genera of the recently described Muribaculaceae, along the gut as well as ASVs that are differentially abundant between segments of treatment and control groups. Overall, this study provides insights into the reversibility of diet-induced microbiota changes and highlights the importance of expanding sampling efforts beyond the collections of fecal samples to characterize diet-dependent and segment-specific microbiome differences.


Assuntos
Microbioma Gastrointestinal/genética , Trato Gastrointestinal/microbiologia , Microbiota/genética , Animais , Bacteroidetes/genética , Bacteroidetes/isolamento & purificação , Dieta Ocidental/efeitos adversos , Fezes/microbiologia , Firmicutes/genética , Firmicutes/isolamento & purificação , Humanos , Camundongos , RNA Ribossômico 16S/genética
15.
Ecotoxicol Environ Saf ; 221: 112464, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34198189

RESUMO

Antibiotics are widely used in the treatment of bacterial infections and as food additives in the livestock industry. The wide usage of antibiotics causes residues in animal products, like milk, eggs and meat. A number of studies have reported that antibiotic residues exist at high concentrations in watercourses around the world. Doxycycline (DH), oxytetracycline (OTCC) and florfenicol (FF) are the three most commonly used veterinary antibiotics in China. However, studies of the toxic effects of DH, OTCC and FF are limited. In this study, six-moth-old healthy male adult zebrafish were exposed to 0, 10, 30, 100 µg/L DH, OTCC or FF for 21 days. After exposure, some biochemical parameters changed significantly, including total cholesterol (TC), triglyceride (TG), pyruvate and acid phosphatase (ACP). In addition, mucus secretion in the gut decreased and the transcription of related genes also decreased significantly. Moreover, the composition of microbiota in the gut changed significantly. DH, OTCC and FF exposure caused the decrease of diversity of gut microbiota. The relative abundance of Proteobacteria increased significantly after OTCC and FF exposure and Fusobacteria decreased in all antibiotic-treated groups. Further functional prediction analysis also suggested changes in gut microbiota in the OTCC and FF-treated groups, especially those linked to metabolism. To support this idea, we confirmed that some glycolipid related genes also increased significantly in the liver of adult zebrafish after antibiotic exposure. According to these results, DH, OTCC or FF exposure could cause the gut microbiota dysbiosis and dysfunction, and hepatic metabolic disorder in adult male zebrafish.


Assuntos
Antibacterianos/toxicidade , Doxiciclina/toxicidade , Disbiose/induzido quimicamente , Microbioma Gastrointestinal/efeitos dos fármacos , Oxitetraciclina/toxicidade , Tianfenicol/análogos & derivados , Animais , Disbiose/metabolismo , Microbioma Gastrointestinal/genética , Glucose/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Tianfenicol/toxicidade , Peixe-Zebra/microbiologia
16.
Nutrients ; 13(7)2021 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-34199047

RESUMO

The gut microbiota has a profound effect on human health and is modulated by food and bioactive compounds. To study such interaction, in vitro batch fermentations are performed with fecal material, and some experimental designs may require that such fermentations be performed with previously frozen stools. Although it is known that freezing fecal material does not alter the composition of the microbial community in 16S rRNA gene amplicon and metagenomic sequencing studies, it is not known whether the microbial community in frozen samples could still be used for in vitro fermentations. To explore this, we undertook a pilot study in which in vitro fermentations were performed with fecal material from celiac, cow's milk allergic, obese, or lean children that was frozen (or not) with 20% glycerol. Before fermentation, the fecal material was incubated in a nutritious medium for 6 days, with the aim of giving the microbial community time to recover from the effects of freezing. An aliquot was taken daily from the stabilization vessel and used for the in vitro batch fermentation of lentils. The microbial community structure was significantly different between fresh and frozen samples, but the variation introduced by freezing a sample was always smaller than the variation among individuals, both before and after fermentation. Moreover, the potential functionality (as determined in silico by a genome-scaled metabolic reconstruction) did not differ significantly, possibly due to functional redundancy. The most affected genus was Bacteroides, a fiber degrader. In conclusion, if frozen fecal material is to be used for in vitro fermentation purposes, our preliminary analyses indicate that the functionality of microbial communities can be preserved after stabilization.


Assuntos
Fermentação , Congelamento , Microbioma Gastrointestinal , Animais , Bovinos , Criança , Fezes/microbiologia , Armazenamento de Alimentos , Microbioma Gastrointestinal/genética , Humanos , Masculino , Microbiota , Leite , Projetos Piloto , RNA Ribossômico 16S/genética
18.
Nutrients ; 13(6)2021 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-34200105

RESUMO

Consumption of prebiotic inulin has been found to increase calcium absorption, which may protect against gut diseases such as colorectal cancer. This dietary relation may be modulated by compositional changes in the gut microbiota; however, no human study has addressed this hypothesis. We determined the feasibility of a randomized crossover trial to evaluate the effect of three interventions (combined calcium and inulin supplementation, calcium supplementation alone, and inulin supplementation alone) on the intestinal microbiota composition and function. We conducted a 16-week pilot study in 12 healthy adults who consumed the three interventions in a random sequence. Participants provided fecal and blood samples before and after each intervention. Each intervention period lasted four weeks and was flanked by one-week washout periods. 16S ribosomal RNA sequencing and quantification of short chain fatty acids (SCFA) was determined in fecal samples. Systemic lipopolysaccharide binding protein (LBP) was quantified in serum. Of the 12 individuals assigned to an intervention sequence, seven completed the study. Reasons for dropout included time (n = 3), gastrointestinal discomfort (n = 1), and moving (n = 1). Overall, participants reported positive attitudes towards the protocol (n = 9) but were unsatisfied by the practicalities of supplement consumption (44%) and experienced digestive discomfort (56%). We found no appreciable differences in microbial composition, SCFA concentration, nor LBP concentrations when comparing intervention periods. In conclusion, an intervention study using a randomized crossover design with calcium and a prebiotic fiber is feasible. Improvements of our study design include using a lower dose prebiotic fiber supplement and a larger sample size.


Assuntos
Cálcio na Dieta/farmacologia , Fibras na Dieta/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Proteínas de Fase Aguda , Adolescente , Adulto , Cálcio na Dieta/administração & dosagem , Proteínas de Transporte/sangue , Estudos Cross-Over , Fibras na Dieta/administração & dosagem , Suplementos Nutricionais , Quimioterapia Combinada , Ácidos Graxos Voláteis/análise , Estudos de Viabilidade , Fezes/química , Feminino , Microbioma Gastrointestinal/genética , Haptoglobinas , Humanos , Insulina/administração & dosagem , Insulina/farmacologia , Masculino , Glicoproteínas de Membrana/sangue , Prebióticos , Precursores de Proteínas/sangue , RNA Ribossômico 16S/genética , Inquéritos e Questionários , Adulto Jovem
19.
Int J Mol Sci ; 22(13)2021 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-34203243

RESUMO

The gut microbiota exists throughout the full life cycle of the human body, and it has been proven to have extensive impacts on health and disease. Accumulating evidence demonstrates that the interplay between gut microbiota and host epigenetics plays a multifaceted role in health maintenance and disease prevention. Intestinal microflora, along with their metabolites, could regulate multiple epigenetic pathways; e.g., DNA methylation, miRNA, or histone modification. Moreover, epigenetic factors can serve as mediators to coordinate gut microbiota within the host. Aiming to dissect this interplay mechanism, the present review summarizes the research profile of gut microbiota and epigenetics in detail, and further interprets the biofunctions of this interplay, especially the regulation of intestinal inflammation, the improvement of metabolic disturbances, and the inhibition of colitis events. This review provides new insights into the interplay of epigenetics and gut microbiota, and attempts to reveal the mysteries of health maintenance and disease prevention from this new perspective.


Assuntos
Epigênese Genética/genética , Animais , Metilação de DNA/genética , Metilação de DNA/fisiologia , Epigenômica , Microbioma Gastrointestinal/genética , Microbioma Gastrointestinal/fisiologia , Humanos , MicroRNAs/metabolismo
20.
Microbiome ; 9(1): 165, 2021 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-34330336

RESUMO

BACKGROUND: A major bottleneck in the use of metagenome sequencing for human gut microbiome studies has been the lack of a comprehensive genome collection to be used as a reference database. Several recent efforts have been made to re-construct genomes from human gut metagenome data, resulting in a huge increase in the number of relevant genomes. In this work, we aimed to create a collection of the most prevalent healthy human gut prokaryotic genomes, to be used as a reference database, including both MAGs from the human gut and ordinary RefSeq genomes. RESULTS: We screened > 5,700 healthy human gut metagenomes for the containment of > 490,000 publicly available prokaryotic genomes sourced from RefSeq and the recently announced UHGG collection. This resulted in a pool of > 381,000 genomes that were subsequently scored and ranked based on their prevalence in the healthy human metagenomes. The genomes were then clustered at a 97.5% sequence identity resolution, and cluster representatives (30,691 in total) were retained to comprise the HumGut collection. Using the Kraken2 software for classification, we find superior performance in the assignment of metagenomic reads, classifying on average 94.5% of the reads in a metagenome, as opposed to 86% with UHGG and 44% when using standard Kraken2 database. A coarser HumGut collection, consisting of genomes dereplicated at 95% sequence identity-similar to UHGG, classified 88.25% of the reads. HumGut, half the size of standard Kraken2 database and directly comparable to the UHGG size, outperforms them both. CONCLUSIONS: The HumGut collection contains > 30,000 genomes clustered at a 97.5% sequence identity resolution and ranked by human gut prevalence. We demonstrate how metagenomes from IBD-patients map equally well to this collection, indicating this reference is relevant also for studies well outside the metagenome reference set used to obtain HumGut. All data and metadata, as well as helpful code, are available at http://arken.nmbu.no/~larssn/humgut/ . Video Abstract.


Assuntos
Microbioma Gastrointestinal , Metagenoma , Microbioma Gastrointestinal/genética , Genoma Humano , Humanos , Metagenômica
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...