RESUMO
Type 2 diabetes mellitus (T2DM) is typically accompanied by sudden weight loss, dyslipidemia-related indicators, decreased insulin sensitivity, and altered gut microbial communities. Fagopyrum tataricum possesses many biological activities, such as antioxidant, hypolipidemic, and hypotensive activities. However, only a few studies have attempted to elucidate the regulatory effects of F. tataricum ethanol extract (FTE) on intestinal microbial communities and its potential relationships with T2DM. In this study, we established a T2DM mouse model and investigated the regulatory effects of FTE on hyperglycemia symptoms and intestinal microbial communities. FTE intervention significantly improved the levels of fasting blood glucose, the area under the curve of oral glucose tolerance test (OGTT), and glycosylated serum protein, as well as pancreas islet function correlation index. In addition, FTE effectively improved hepatic and cecum injuries and insulin secretion due to T2DM. It was also revealed that the potential hypoglycemic mechanism of FTE was involved in the regulation of protein kinase B (AKT-1) and glucose transporter 2 (GLUT-2). Furthermore, compared with the Model group, the FTE-H intervention exhibited a significantly decreased ratio of Firmicutes to Bacteroidetes at the phylum level, reduced relative abundance of pernicious bacteria at the genus level, such as Desulfovibrio, Oscillibacter, Blautia, Parabacteroides, and Erysipelatoclostridium, and ameliorated inflammatory response and insulin resistance. Moreover, the correlation between gut microbiota and hypoglycemic indicators was predicted. The results showed that Lachnoclostridium, Lactobacillus, Oscillibacter, Bilophila, and Roseburia have the potential to be used as bacterial markers for T2DM. In conclusion, our research showed that FTE alleviates hyperglycemia symptoms by regulating the expression of AKT-1 and GLUT-2, as well as intestinal microbial communities in T2DM mice.
Assuntos
Diabetes Mellitus Tipo 2 , Fagopyrum , Microbioma Gastrointestinal , Hiperglicemia , Lactobacillales , Animais , Camundongos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Proteínas Proto-Oncogênicas c-akt , Hiperglicemia/tratamento farmacológico , Hipoglicemiantes , Firmicutes , Bacteroidetes , Clostridiales , Etanol , Extratos VegetaisRESUMO
Psoriasis, a chronic and systemic inflammatory disorder characterized by activation of the interleukin (IL)-23/IL-17 axis, may be associated with the intestinal microbiota through the so-called "gut-skin axis." Clusterin is a glycoprotein ubiquitously distributed in mammalian tissues; however, its role in psoriasis is unclear. Therefore, we evaluated the role of clusterin in psoriatic skin inflammation, systemic inflammation, and colitis using a murine model of IMQ-induced psoriasis. In IMQ-treated clusterin-knockout (clusterin-/-) mice, the expressions of inflammatory cytokines in clusterin-silenced human keratinocytes and intestinal microbial composition were analyzed. We also examined clusterin expression in the skin tissues of patients with psoriasis. IMQ-induced psoriatic skin inflammation is suppressed in clusterin-/- mice. Long-term administration of IMQ induced systemic inflammation and colitis; however, both were alleviated by the genetic deletion of clusterin. Genetic silencing of clusterin in human keratinocytes inhibited the production of inflammatory cytokines involved in the initiation and progression of psoriasis. The composition of the intestinal microbiota in IMQ-treated clusterin-/- and wild-type mice was different. Genetic deletion of clusterin suppressed the increase in the Firmicutes/Bacteroidetes (F/B) ratio. Skin tissues of patients with psoriasis showed high clusterin expression. In conclusion, inhibition of clusterin decreased psoriatic skin inflammation, systemic inflammation, colitis, and altered the F/B ratio in an IMQ-induced murine psoriasis model.
Assuntos
Colite , Dermatite , Microbioma Gastrointestinal , Psoríase , Humanos , Animais , Camundongos , Clusterina/genética , Psoríase/induzido quimicamente , Psoríase/genética , Colite/induzido quimicamente , Colite/genética , Inflamação , Bacteroidetes , Citocinas , Firmicutes , MamíferosRESUMO
BACKGROUND: The microbiota of the upper respiratory tract is increasingly recognized as a gatekeeper of respiratory health. Despite this, the microbiota of healthy adults remains understudied. To address this gap, we investigated the composition of the nasopharyngeal and oropharyngeal microbiota of healthy adults, focusing on the effect of Streptococcus pneumoniae carriage, smoking habits, and contact with children. RESULTS: Differential abundance analysis indicated that the microbiota of the oropharynx was significantly different from that of the nasopharynx (P < 0.001) and highly discriminated by a balance between the classes Negativicutes and Bacilli (AUC of 0.979). Moreover, the oropharynx was associated with a more homogeneous microbiota across individuals, with just two vs. five clusters identified in the nasopharynx. We observed a shift in the nasopharyngeal microbiota of carriers vs. noncarriers with an increased relative abundance of Streptococcus, which summed up to 30% vs. 10% in noncarriers and was not mirrored in the oropharynx. The oropharyngeal microbiota of smokers had a lower diversity than the microbiota of nonsmokers, while no differences were observed in the nasopharyngeal microbiota. In particular, the microbiota of smokers, compared with nonsmokers, was enriched (on average 16-fold) in potential pathogenic taxa involved in periodontal diseases of the genera Bacillus and Burkholderia previously identified in metagenomic studies of cigarettes. The microbiota of adults with contact with children resembled the microbiota of children. Specifically, the nasopharyngeal microbiota of these adults had, on average, an eightfold increase in relative abundance in Streptococcus sp., Moraxella catarrhalis, and Haemophilus influenzae, pathobionts known to colonize the children's upper respiratory tract, and a fourfold decrease in Staphylococcus aureus and Staphylococcus lugdunensis. CONCLUSIONS: Our study showed that, in adults, the presence of S. pneumoniae in the nasopharynx is associated with a shift in the microbiota and dominance of the Streptococcus genus. Furthermore, we observed that smoking habits are associated with an increase in bacterial genera commonly linked to periodontal diseases. Interestingly, our research also revealed that adults who have regular contact with children have a microbiota enriched in pathobionts frequently carried by children. These findings collectively contribute to a deeper understanding of how various factors influence the upper respiratory tract microbiota in adults. Video Abstract.
Assuntos
Bacillus , Microbiota , Adulto , Criança , Humanos , Streptococcus pneumoniae/genética , Fumar , Nariz , Metagenoma , FirmicutesRESUMO
The human gut microbiota is a complex ecology comprising approximately 10 to 100 trillion microbial cells. Most of the bacteria detected by 16s rRNA sequencing have yet to be cultured, but intensive attempts to isolate the novel bacteria have improved our knowledge of the gut microbiome composition and its roles within human host. In our culturomics study, a novel gram-negative, motile, obligately anaerobic, rod-shaped bacteria, designated as strain ICN-92133T, was isolated from a fecal sample of a 26-year-old patient with Crohn's disease. Based on the 16s rRNA sequence of strain ICN-92133T, the phylogeny analysis placed the strain into the family Selenomonadaceae, showing 93.91% similarity with the closely related Massilibacillus massiliensis strain DSM 102838T. Strain ICN-92133T exhibited a genome size of 2,679,003 bp with a GC content of 35.5% which was predicted to contain 26 potential virulence factors and five antimicrobial resistance genes. In comparative genomic analysis, strain ICN-92133T showed digital DNA-DNA Hybridization and OrthoANI values lower than 21.9% and 71.9% with the closest type strains, respectively. In addition, comparing phenotypic, biochemical, and cellular fatty acids with those of closely related strains revealed the distinctiveness of strain ICN-92133T. Based on the taxonogenomic results, strain ICN-92133T is proposed as a novel species belonging to a new genus. Therefore, we suggest the name of the new genus Selenobaculum gen. nov. within the family Selenomonadaceae and strain ICN-92133T (= KCTC 25622T = JCM 36070T) as a type strain of new species Selenobaculum gbiensis sp. nov.
Assuntos
Doença de Crohn , Microbioma Gastrointestinal , Humanos , Adulto , Microbioma Gastrointestinal/genética , RNA Ribossômico 16S/genética , Bactérias , Firmicutes , DNARESUMO
Symbiotic microorganisms modulate systemic immunity with unclear mechanisms. In this issue of Cell Host & Microbe, Clarke and colleagues uncover a coherent mechanism where the systemic spread of Firmicutes cell wall glycoconjugates enhances global immune fitness while simultaneously being delicately controlled to prevent systemic inflammation.
Assuntos
Parede Celular , Firmicutes , Humanos , InflamaçãoRESUMO
Honokiol (HNK), one of the main active components of Magnolia officinalis, has a positive effect on non-alcoholic steatohepatitis (NASH). However, the effects of HNK on the composition of serum lipids and bile acids (BAs) and gut microbiota (GM) of NASH mice are still unknown.C57BL/6 mice were fed with methionine-choline deficiency (MCD) diet and gavaged with HNK (20 mg/kg/d) for 8 weeks, then the serum lipids and BAs were detected by LC-MS, the composition of ileum microflora and the mRNA expression of hepatic BAs homeostasis related genes were analyzed by 16S rDNA sequencing and RT-qPCR, respectively. HNK treatment decreased the degree of hepatic lipid drops, inflammatory cell infiltration and fibrosis. Meantime, the serum levels of 34 lipids and 4 BAs in MCD mice were significantly altered by HNK treatment, as well as the increased abundance of Ruminococcaceae, Caulobacteraceae and Brevundimonas, and the decreased abundance of Firmicutes and Dubosiella. Besides, HNK treatment increased the hepatic mRNA expression of Oatp1b2 in MCD mice. The ameliorating effect of HNK on NASH may be partly related to its correction on the disorders of GM, serum lipids and BAs of MCD mice.
Assuntos
Caulobacteraceae , Deficiência de Colina , Microbioma Gastrointestinal , Hepatopatia Gordurosa não Alcoólica , Animais , Camundongos , Camundongos Endogâmicos C57BL , Metionina , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/etiologia , Racemetionina , Dieta , Ácidos e Sais Biliares , Firmicutes , Lipídeos , RNA MensageiroRESUMO
BACKGROUND: Gut microbiota plays a significant role in host survival, health, and diseases; however, compared to other livestock, research on the gut microbiome of donkeys is limited. RESULTS: In this study, a total of 30 donkey samples of rectal contents from six regions, including Shigatse, Changdu, Yunnan, Xinjiang, Qinghai, and Dezhou, were collected for metagenomic sequencing. The results of the species annotation revealed that the dominant phyla were Firmicutes and Bacteroidetes, and the dominant genera were Bacteroides, unclassified_o_Clostridiales (short for Clostridiales) and unclassified_f_Lachnospiraceae (short for Lachnospiraceae). The dominant phyla, genera and key discriminators were Bacteroidetes, Clostridiales and Bacteroidetes in Tibet donkeys (Shigatse); Firmicutes, Clostridiales and Clostridiales in Tibet donkeys (Changdu); Firmicutes, Fibrobacter and Tenericutes in Qinghai donkeys; Firmicutes, Clostridiales and Negativicutes in Yunnan donkeys; Firmicutes, Fibrobacter and Fibrobacteres in Xinjiang donkeys; Firmicutes, Clostridiales and Firmicutes in Dezhou donkeys. In the functional annotation, it was mainly enriched in the glycolysis and gluconeogenesis of carbohydrate metabolism, and the abundance was the highest in Dezhou donkeys. These results combined with altitude correlation analysis demonstrated that donkeys in the Dezhou region exhibited strong glucose-conversion ability, those in the Shigatse region exhibited strong glucose metabolism and utilization ability, those in the Changdu region exhibited a strong microbial metabolic function, and those in the Xinjiang region exhibited the strongest ability to decompose cellulose and hemicellulose. CONCLUSION: According to published literature, this is the first study to construct a dataset with multi-regional donkey breeds. Our study revealed the differences in the composition and function of gut microbes in donkeys from different geographic regions and environmental settings and is valuable for donkey gut microbiome research.
Assuntos
Equidae , Microbioma Gastrointestinal , Bacteroidetes , China , Clostridiales , Firmicutes , Equidae/microbiologiaRESUMO
The bacterial diversity in Populus euphratica stem storage liquid samples grown in Shaya County and Yuli County of the Tarim River Basin was investigated. A culture-dependent (dilution spread plate method) and culture-independent method (PCR-RFLP technique) were used to identify the endophytic bacteria community structure and composition in P. euphratica in Tarim River Basin. Sixty-six bacterial strains were isolated from P. euphratica stem storage liquid samples on three agar media. The 16S rDNA gene was amplified and sequenced using bacterial universal primers. Phylogenetic analysis showed that the 66 strains belonged to three phyla (Firmicutes, Actinomycetes, and Gamma-Proteobacteria) and included 16 genera and 29 species. Among them, Pseudomonas (27.27%) and Bacillus (19.69%) were the dominant isolates. CGM-17 was a potentially new species of Pantoea. Restriction fragment length polymorphism of 16S rDNA gene amplified by polymerase chain reaction (PCR-RFLP) revealed 48 operational taxonomic units (OTUs). Phylogenetic analysis indicated that the 48 OTUs belonged to Firmicutes, Actinobacteria, Proteobacteria (α-, ß-, γ-subgroup), Bacteroidetes, and Verrucomicrobia. Gamma-Proteobacteria was the dominant group, similarly to the culture-dependent method, accounting for 53% of the entire bacterial clone library. Our results indicate that P. euphratica endophytic bacteria diversity in the Tarim River Basin was rich, and the resources of endophytic bacteria were high. They provide valuable reference data and species resources for screening indigenous and functional strains of endophytic bacteria in P. euphratica.
Assuntos
Actinobacteria , Gammaproteobacteria , Populus , Filogenia , Rios , Bactérias/genética , Firmicutes , China , DNA RibossômicoRESUMO
Background: Rhizosphere bacteria play important roles in plant growth and secondary metabolite accumulation. Moreover, only with favorable production areas and desirable germplasm can high-yield and high-quality medicinal materials be produced. However, whether origin and germplasm indirectly affect the yield and quality of Angelica dahurica var. formosana through rhizosphere bacterial effects are not known. Methods: In this study, a high-throughput sequencing strategy was used to explore the relationship between the rhizosphere bacterial community and the cultivation of A. dahurica var. formosana from different production areas and germplasm for the first time. Results: (1) Proteobacteria was the dominant bacterial phylum in the rhizosphere soil of A. dahurica var. formosana, and these bacteria were stable and conserved to a certain extent. (2) High abundance of Proteobacteria was an important rhizospheric indicator of high yield, and high abundance of Firmicutes was an important indicator of high quality. Proteobacteria and Firmicutes might have an important relationship with the yield and quality of A. dahurica var. formosana, respectively. (3) PCoA cluster analysis demonstrated that both production area and germplasm affected the bacterial community structure in the rhizosphere of A. dahurica var. formosana to a certain extent, and production area had the greatest effect. In addition to available potassium, the rhizosphere soil nutrient levels of different production areas strongly affected the bacterial diversity and community. These findings provide a theoretical basis for the exploitation and utilization of rhizosphere microbial resources of A. dahurica var. formosana and offer a novel approach for increasing the yield and quality of this crop.
Assuntos
Angelica , Gastrópodes , Animais , Rizosfera , Bactérias/genética , Proteobactérias/genética , Firmicutes , SoloRESUMO
Methane production by microbial fermentation of municipal waste is a challenge for better yield processes. This work describes the characterization of a hydrogenotrophic methanogen microbial community used in a bioaugmentation procedure to improve the methane yield in a thermophilic anaerobic process, digesting the organic fraction of municipal solid waste. The performance of the bioaugmentation was assessed in terms of methane production and changes in the microbial community structure. The results showed that bioaugmentation slightly improved the cumulative methane yield (+ 4%) in comparison to the control, and its use led to an acceleration of the methanogenesis stage. We observed associated significant changes in the relative abundance of taxa and their interactions, using high throughput DNA sequencing of V3-16S rRNA gene libraries, where the abundance of the archaeal hydrogenotrophic genus Methanoculleus (class Methanomicrobia, phylum Euryarchaeota) and the bacterial order MBA08 (class Clostridia, phylum Firmicutes) were dominant. The relevant predicted metabolic pathways agreed with substrate degradation and the anaerobic methanogenic process. The purpose of the study was to evaluate the effect of the addition of hydrogenotrophic methanogens in the generation of methane, while treating organic waste through anaerobic digestion.
Assuntos
Euryarchaeota , Microbiota , Anaerobiose , Metano/metabolismo , RNA Ribossômico 16S/genética , Reatores Biológicos/microbiologia , Euryarchaeota/genética , Euryarchaeota/metabolismo , Microbiota/genética , Firmicutes/metabolismoRESUMO
Extracellular synthesis of functional cyclodextrins (CDs) as intermediates of starch assimilation is a convenient microbial adaptation to sequester substrates, increase the half-life of the carbon source, carry bioactive compounds, and alleviate chemical toxicity through the formation of CD-guest complexes. Bacteria encoding the four steps of the carbohydrate metabolism pathway via cyclodextrins (CM-CD) actively internalize CDs across the microbial membrane via a putative type I ATP-dependent ABC sugar importer system, MdxEFG-(X/MsmX). While the first step of the CM-CD pathway encompasses extracellular starch-active cyclomaltodextrin glucanotransferases (CGTases) to synthesize linear dextrins and CDs, it is the ABC importer system in the second step that is the critical factor in determining which molecules from the CGTase activity will be internalized by the cell. Here, structure-function relationship studies of the cyclo/maltodextrin-binding protein MdxE of the MdxEFG-MsmX importer system from Thermoanaerobacter mathranii subsp. mathranii A3 are presented. Calorimetric and fluorescence studies of recombinant MdxE using linear dextrins and CDs showed that although MdxE binds linear dextrins and CDs with high affinity, the open-to-closed conformational change is solely observed after α- and ß-CD binding, suggesting that the CM-CD pathway from Thermoanaerobacterales is exclusive for cellular internalization of these molecules. Structural analysis of MdxE coupled with docking simulations showed an overall architecture typically found in sugar-binding proteins (SBPs) that comprised two N- and C-domains linked by three small hinge regions, including the conserved aromatic triad Tyr193/Trp269/Trp378 in the C-domain and Phe87 in the N-domain involved in CD recognition and stabilization. Structural bioinformatic analysis of the entire MdxFG-MsmX importer system provided further insights into the binding, internalization, and delivery mechanisms of CDs. Hence, while the MdxE-CD complex couples to the permease subunits MdxFG to deliver the CD into the transmembrane channel, the dimerization of the cytoplasmatic promiscuous ATPase MsmX triggers active transport into the cytoplasm. This research provides the first results on a novel thermofunctional SBP and its role in the internalization of CDs in extremely thermophilic bacteria.
Assuntos
Proteínas de Transporte , Dextrinas , Proteínas de Transporte/genética , Polissacarídeos , Firmicutes , Bactérias Anaeróbias , AmidoRESUMO
The intestinal microbiota regulates immunity across organ systems. Which symbionts control systemic immunity, the mechanisms they use, and how they avoid widespread inflammatory damage are unclear. We uncover host tolerance and resistance mechanisms that allow Firmicutes from the human microbiota to control systemic immunity without inducing immunopathology. Intestinal processing releases Firmicute glycoconjugates that disseminate, resulting in release of cytokine IL-34 that stimulates macrophages and enhances defenses against pneumonia, sepsis, and meningitis. Despite systemic penetration of Firmicutes, immune homeostasis is maintained through feedback control whereby IL-34-mediated mTORC1 activation in macrophages clears polymeric glycoconjugates from peripheral tissues. Smaller glycoconjugates evading this clearance mechanism are tolerated through sequestration by albumin, which acts as an inflammatory buffer constraining their immunological impact. Without these resistance and tolerance mechanisms, Firmicutes drive catastrophic organ damage and cachexia via IL-1ß. This reveals how Firmicutes are safely assimilated into systemic immunity to protect against infection without threatening host viability.
Assuntos
Firmicutes , Microbiota , Humanos , Simbiose , Tolerância Imunológica , Citocinas , Interleucinas , Imunidade InataRESUMO
The gut microbiota is a complex ecosystem that interacts with many other factors to affect the health and disease states of the host. The common kestrel (Falco tinnunculus) is protected at the national level in China. However, the available sequencing data of the gut microbiota from the feces of wild common kestrels, especially for being rescued individuals by professional organization, remains limited. In the present study, we characterized the fecal bacterial communities of healthy and injured common kestrels, and compared the structure of their fecal microbiota by analyzing the V3-V4 region of the 16S rRNA gene using high-throughput sequencing technology with the Illumina MiSeq platform. We found that Firmicutes, Proteobacteria and Actinobacteria were the most predominant phyla in common kestrels. Further, the beta diversity analysis showed that changes in gut microbes were associated with injuries to the common kestrel. The Bacteroides/Firmicutes ratio was significantly lower in the injured group. At the genus level, Glutamicibacter showed significant difference in the two groups. The aim of our current study was to characterize the basic bacterial composition and community structure in the feces of healthy common kestrels, and then compare the differences in the fecal microbiota between healthy and injured individuals. Patescibacteria, Spirochaetes, and Glutamicibacter may be studied as potential biomarkers for certain diseases in raptors. The results could provide the basic data for additional research on the fecal microbiota of common kestrels and contribute to the rescue of wild raptors in the future.
Assuntos
Falconiformes , Microbiota , Micrococcaceae , Aves Predatórias , Humanos , Animais , Pequim , RNA Ribossômico 16S/genética , Firmicutes , Fezes , Proteína Regulatória Associada a mTORRESUMO
Certain bacterial strains from the microbiome induce a potent, antigen-specific T cell response1-5. However, the specificity of microbiome-induced T cells has not been explored at the strain level across the gut community. Here, we colonize germ-free mice with complex defined communities (roughly 100 bacterial strains) and profile T cell responses to each strain. The pattern of responses suggests that many T cells in the gut repertoire recognize several bacterial strains from the community. We constructed T cell hybridomas from 92 T cell receptor (TCR) clonotypes; by screening every strain in the community against each hybridoma, we find that nearly all the bacteria-specific TCRs show a one-to-many TCR-to-strain relationship, including 13 abundant TCR clonotypes that each recognize 18 Firmicutes. By screening three pooled bacterial genomic libraries, we discover that these 13 clonotypes share a single target: a conserved substrate-binding protein from an ATP-binding cassette transport system. Peripheral regulatory T cells and T helper 17 cells specific for an epitope from this protein are abundant in community-colonized and specific pathogen-free mice. Our work reveals that T cell recognition of commensals is focused on widely conserved, highly expressed cell-surface antigens, opening the door to new therapeutic strategies in which colonist-specific immune responses are rationally altered or redirected.
Assuntos
Bactérias , Microbioma Gastrointestinal , Linfócitos T , Animais , Camundongos , Antígenos de Superfície/imunologia , Bactérias/classificação , Bactérias/imunologia , Firmicutes/imunologia , Microbioma Gastrointestinal/imunologia , Linfócitos T Reguladores/imunologia , Células Th17/imunologia , Linfócitos T/imunologia , Simbiose/imunologia , Vida Livre de Germes , Receptores de Antígenos de Linfócitos T/imunologia , Hibridomas/citologia , Hibridomas/imunologia , Separação CelularRESUMO
Alkaline lakes are a special aquatic ecosystem that act as important water and alkali resource in the arid-semiarid regions. The primary aim of the study is to explore how environmental factors affect community diversity and structure, and to find whether there are key microbes that can indicate changes in environmental factors in alkaline lakes. Therefore, four sediment samples (S1, S2, S3, and S4) were collected from Hamatai Lake which is an important alkali resource in Ordos' desert plateau of Inner Mongolia. Samples were collected along the salinity and alkalinity gradients and bacterial community compositions were investigated by Illumina Miseq sequencing. The results revealed that the diversity and richness of bacterial community decreased with increasing alkalinity (pH) and salinity, and bacterial community structure was obviously different for the relatively light alkaline and hyposaline samples (LAHO; pH < 8.5; salinity < 20) and high alkaline and hypersaline samples (HAHR; pH > 8.5; salinity > 20). Firmicutes, Proteobacteria and Bacteriodetes were observed to be the dominant phyla. Furthermore, Acidobacteria, Actinobacteria, and low salt-tolerant alkaliphilic nitrifying taxa were mainly distributed in S1 with LAHO characteristic. Firmicutes, Clostridia, Gammaproteobacteria, salt-tolerant alkaliphilic denitrifying taxa, haloalkaliphilic sulfur cycling taxa were mainly distributed in S2, S3 and S4, and were well adapted to haloalkaline conditions. Correlation analysis revealed that the community diversity (operational taxonomic unit numbers and/or Shannon index) and richness (Chao1) were significantly positively correlated with ammonium nitrogen (r = 0.654, p < 0.05; r = 0.680, p < 0.05) and negatively correlated with pH (r = -0.924, p < 0.01; r = -0.800, p < 0.01; r = -0.933, p < 0.01) and salinity (r = -0.615, p < 0.05; r = -0.647, p < 0.05). A redundancy analysis and variation partitioning analysis revealed that pH (explanation degrees of 53.5%, pseudo-F = 11.5, p < 0.01), TOC/TN (24.8%, pseudo-F = 10.3, p < 0.05) and salinity (9.2%, pseudo-F = 9.5, p < 0.05) were the most significant factors that caused the variations in bacterial community structure. The results suggested that alkalinity, nutrient salt and salinity jointly affect bacterial diversity and community structure, in which one taxon (Acidobacteria), six taxa (Cyanobacteria, Nitrosomonadaceae, Nitrospira, Bacillus, Lactococcus and Halomonas) and five taxa (Desulfonatronobacter, Dethiobacter, Desulfurivibrio, Thioalkalivibrio and Halorhodospira) are related to carbon, nitrogen and sulfur cycles, respectively. Classes Clostridia and Gammaproteobacteria might indicate changes of saline-alkali conditions in the sediments of alkaline lakes in desert plateau.
Assuntos
Ectothiorhodospiraceae , Lagos , Ecossistema , Bactérias/genética , Firmicutes , Acidobacteria , China , ÁlcalisRESUMO
Objective: The gut micro-biome plays a pivotal role in the progression of lung cancer. However, the specific mechanisms by which the intestinal microbiota and its metabolites are involved in the lung cancer process remain unclear. Method: Stool samples from 52 patients with lung cancer and 29 healthy control individuals were collected and subjected to 16S rRNA gene amplification sequencing and non-targeted gas/liquid chromatography-mass spectrometry metabolomics analysis. Then microbiota, metabolites and potential signaling pathways that may play an important role in the disease were filtered. Results: Firmicutes, Clostridia, Bacteroidacea, Bacteroides, and Lachnospira showed a greater abundance in healthy controls. In contrast, the Ruminococcus gnavus(R.gnavus) was significantly upregulated in lung cancer patients. In this respect, the micro-biome of the squamous cell carcinoma(SCC)group demonstrated a relatively higher abundance of Proteobacteria, Gammaproteobacteria, Bacteroides,and Enterobacteriaceae, as well as higher abundances of Fusicatenibacter and Roseburia in adenocarcinoma(ADC) group. Metabolomic analysis showed significant alterations in fecal metabolites including including quinic acid, 3-hydroxybenzoic acid,1-methylhydantoin,3,4-dihydroxydrocinnamic acid and 3,4-dihydroxybenzeneacetic acid were significantly altered in lung cancer patients. Additionally, the R.gnavus and Fusicatenibacter of lung cancer were associated with multiple metabolite levels. Conclusion: Our study provides essential guidance for a fundamental systematic and multilevel assessment of the contribution of gut micro-biome and their metabolites in lung cancer,which has great potential for understanding the pathogenesis of lung cancer and for better early prevention and targeted interventions.
Assuntos
Microbioma Gastrointestinal , Neoplasias Pulmonares , Humanos , Microbioma Gastrointestinal/genética , RNA Ribossômico 16S/genética , Fezes/microbiologia , Metabolômica/métodos , Firmicutes/genéticaRESUMO
The gastrointestinal microbiota plays an important role in the function of the host intestine. However, little is currently known about the effects of irradiation on the microorganisms colonizing the mucosal surfaces of the gastrointestinal tract. The aim of this study was to investigate the effects of X-ray irradiation on the compositions of the large intestinal Microbiotas of the rat. The gut microbiotas in control mice and mice receiving irradiation with different dose treatment were characterized by high-throughput sequencing of the bacterial 16S rDNA gene and their metabolites were detected by gas chromatography-mass spectrometry. Unexpectedly, the diversity was increased mildly at 2Gy irradiation, and dose dependent decreased at 4Gy, 6Gy, 8Gy irradiation. The phyla with large changes in phylum level are Firmicutes, Bacteroides and Proteobacteria; the abundance ratio of Firmicutes/Bacteroides is inverted; and when 8Gy is irradiated, the phylum abundance level was significantly increased. At the genus level, the abundance levels of Phascolarctobacterium, Ruminococcaceae and Lachnospiraceae increased at 2Gy irradiation, and significantly decreased at 4Gy, 6Gy, and 8Gy irradiation; the abundance level of Prevotellaceae diminished at 2Gy irradiation, and enhanced at 4Gy, 6Gy, 8Gy irradiation; The abundance level of Violet bacteria (Christenellaceae) and Lactobacillus attenuated in a dose-dependent manner; Lachnoclostridium enhanced in a dose-dependent manner; Bacteroides was in 4Gy, 6Gy, 8Gy The abundance level increased significantly during irradiation; the abundance level of Shigella (Escherichia-Shigella) only increased significantly during 8Gy irradiation. Lefse predicts that the biomarker at 0Gy group is Veillonellaceae, the biomarker at 2Gy group is Firmicutes, the biomarkers at 4Gy group are Dehalobacterium and Dehalobacteriaceae, the biomarkers at 6Gy group are Odoribacter, and the biomarkers at 8Gy group are Anaerotruncus, Holdemania, Proteus, Bilophila, Desufovibrionales and Deltaproteobacteria. Overall, the data presented here reveal that X-ray irradiation can cause imbalance of the intestinal flora in rats; different doses of irradiation can cause different types of bacteria change. Representative bacteria can be selected as biomarkers for radiation damage and repair.This may contribute to the development of radiation resistance in the future.
Assuntos
Microbioma Gastrointestinal , Microbiota , Ratos , Camundongos , Animais , Microbioma Gastrointestinal/genética , Bactérias/genética , Trato Gastrointestinal , Firmicutes/genética , Biomarcadores , Bacteroidetes/genética , Clostridiales/genética , RNA Ribossômico 16S/genéticaRESUMO
BACKGROUND: Fermented Aloe leaf juice is a commonly used food supplement in Japan. In a previous study, fermentation of A. arborescence juice was performed and the presence of short-chain fatty acids (SCFAs) was confirmed and quantified. Samples were collected before and after the fermentation process to be subjected, in the present study, to DNA extraction, 16S rRNA gene (V3-V4 regions) amplification, and sequencing by the next-generation Illumina MiSeq sequencer. Our work aims to analyze the sequences to assess the bacterial diversity in the juice before and after fermentation, identify the beneficial microbes responsible for the production of SCFAs, and evaluate some of the biological activities of the fermented juice. RESULTS: Data revealed the richness and diversity of the bacterial community in the fermented juice compared to the unfermented control. Relative abundance of bacterial phyla showed that the majority of the microbial community in the test samples corresponded to Pseudomonadota (unfermented; 10.4%, fermented; 76.36%), followed by Bacillota (unfermented; 4.71%, fermented; 17.13%) and then Bacteroidota (unfermented; 0.57%, fermented; 1.64%). For the fermented sample, 84% of Bacillota were lactobacilli. A hierarchically clustered heatmap revealed that Lactobacillus was the most abundant genus in both samples suggesting its involvement in the production of SCFAs. To assess potential health benefits, the anticancer efficacy of the fermented product of A. arborescens was investigated against colorectal cancer (IC50 = 3.5 µg/ml) and liver cancer (IC50 = 6.367 µg/ml) compared to the normal peripheral blood mononuclear cells (PBMCs). Flow cytometric analysis of the cell cycle pattern revealed remarkable population arrest in G0 and G1, however, the highest percentages were mainly in the G1 phase for Hep-G2 (40.1%) and HCT-116 (53.2%) cell lines. This effect was accompanied by early apoptotic profiles of HCT-116 (36.9%) and late apoptosis for Hep-G2 (17.3%). Furthermore, immunomodulatory properties demonstrated a significantly (p < 0.001) reduced percentage of induced TNF-α while enhancing IFN-γ dramatically. For antimicrobial activities, marked broad-spectrum activities were recorded against some bacterial and fungal pathogens (17-37 mm inhibition zone diameter range). CONCLUSION: Therefore, this study affords the basis of bacterial community composition in fermented A. arborescens juice as well as its potential biological benefits.
Assuntos
Aloe , Anti-Infecciosos , Leucócitos Mononucleares , RNA Ribossômico 16S/genética , Anti-Infecciosos/farmacologia , Firmicutes , Ácidos Graxos Voláteis , LactobacillusRESUMO
Arsenic poses a significant health risk worldwide, impacting the gut microbiota, reproductive health, and development. To address this issue, a cost-effective method like probiotic supplementation could be beneficial. However, the interplay between arsenic toxicity, probiotics, gut microbiota, and maternal transcript modulation remains unexplored. This study investigates the impact of Lactobacillus rhamnosus (L. rhamnosus) DSM 20021 on the proportions of Firmicutes and Bacteroidetes, as well as its effects on embryonic development in zebrafish induced by arsenic trioxide (As2O3). Adult zebrafish were exposed to both high and environmentally relevant concentrations of As2O3 (10, 50, and 500 ppb) for 1, 6, and 12 weeks. qPCR analysis revealed increased proportions of Firmicutes and Bacteroidetes in all As2O3-exposed and As2O3 + L. rhamnosus-exposed groups, while no significant changes were observed in groups exposed only to L. rhamnosus DSM 20021. The larvae, exposed to 500 ppb of As2O3 for 12 weeks, exhibited low growth, decreased survival rates, and morphological deformities. However, these adverse effects were reversed upon exposure to only L. rhamnosus DSM 20021. Furthermore, the expression of DVR1 and ABCC5, which are involved in defense against xenobiotics and embryo development, decreased significantly in As2O3 (500 ppb) and As2O3 (500 ppb) + L. rhamnosus-exposed groups, whereas ameliorative effects were observed in only L. rhamnosus DSM 20021-exposed groups.
Assuntos
Arsênio , Lacticaseibacillus rhamnosus , Feminino , Animais , Arsênio/toxicidade , Firmicutes , Peixe-Zebra , Desenvolvimento Embrionário , Bacteroidetes/genéticaRESUMO
The microbial community of the landfill undergoing aerobic stabilization process by aeration engineering was investigated. The municipal solid wastes (MSWs) were sampled from two aeration well sites with different landfill temperatures (65.5°C and 41.7°C) under higher and lower stabilization level. The physical component, chemical property, and microbial population of MSWs were analyzed and compared. The result showed that the phylum Firmicutes was dominant in the aerobic landfill; and the genus Weissella and Syntrophaceticus were more abundant in high, and low temperature site, respectively. The bacterial distribution showed difference on two temperature sites and four landfill depths, mainly affected by the ammonia-nitrogen and moisture content of MSWs. The ecological profiles of the microorganisms responded the aeration engineering were predicted. The anaerobic hydrolytic and acetogenic microorganisms were decreased in abundance, while the facultative Lactobacillus increased when the landfill under a higher stabilization level. The function abundances of methane oxidation, sulfide oxidation, and aerobic chemoheterotrophy were enriched by aeration engineering, which was the microbial mechanism for accelerating the stabilization process of landfill.