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NPJ Biofilms and Microbiomes Nov 2023Accumulated evidence supports the beneficial role of inulin in alleviating metabolic dysfunction-associated fatty liver disease (MAFLD) by modulating gut microbiota....
Accumulated evidence supports the beneficial role of inulin in alleviating metabolic dysfunction-associated fatty liver disease (MAFLD) by modulating gut microbiota. However, the underlying mechanisms are not fully understood. Here we used high-fat diet (HFD)-induced laying hen model of MAFLD to investigate the effect of inulin on ameliorating MAFLD and found that the inulin-enriched Megamonas genus was inversely correlated with hepatic steatosis-related parameters. Oral administration of a newly isolated commensal bacterium by culturomics, M. funiformis CML154, to HFD-fed hens and mice ameliorated MAFLD, changed liver gene expression profiles, and increased intestinal propionate concentration. Further evidence demonstrated that the anti-MAFLD effect of M. funiformis CML154 is attributed to propionate-mediated activation of the APN-AMPK-PPARα signaling pathway, thereby inhibiting fatty acid de novo synthesis and promoting β-oxidation. These findings establish the causal relationships among inulin, M. funiformis, and MAFLD, and suggest that M. funiformis CML154 is a probiotic candidate for preventative or therapeutic intervention of MAFLD.
Topics: Animals; Female; Mice; Propionates; Inulin; Chickens; Non-alcoholic Fatty Liver Disease
PubMed: 37925493
DOI: 10.1038/s41522-023-00451-y -
Scientific Reports Dec 2022Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in children and adolescents. The gut microbiota plays an important role in the...
Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in children and adolescents. The gut microbiota plays an important role in the pathophysiology of NAFLD through the gut-liver axis. Therefore, we aimed to investigate the genus and species of gut microbiota and their functions in children and adolescents with NAFLD. From May 2017 to July 2018, a total of 58 children and adolescents, including 27 abnormal weight (AW) (obese) NAFLD patients, 16 AW non-NAFLD children, and 15 healthy children, were enrolled in this study at Shenzhen Children's Hospital. All of them underwent magnetic resonance spectroscopy (MRS) to quantify the liver fat fraction. Stool samples were collected and analysed with metagenomics. According to body mass index (BMI) and MRS proton density fat fraction (MRS-PDFF), we divided the participants into BMI groups, including the AW group (n = 43) and the Lean group (n = 15); MRS groups, including the NAFLD group (n = 27) and the Control group (n = 31); and BMI-MRS 3 groups, including NAFLD_AW (AW children with NAFLD) (n = 27), Ctrl_AW (n = 16) (AW children without NAFLD) and Ctrl_Lean (n = 15). There was no difference in sex or age among those groups (p > 0.05). In the BMI groups, at the genus level, Dialister, Akkermansia, Odoribacter, and Alistipes exhibited a significant decrease in AW children compared with the Lean group. At the species level, Megamonas hypermegale was increased in the AW group, while Akkermansia muciniphila, Dialister invisus, Alistipes putredinis, Bacteroides massiliensis, Odoribacter splanchnicus, and Bacteroides thetaiotaomicron were decreased in AW children, compared to the Lean group. Compared with the Control group, the genus Megamonas, the species of Megamonas hypermegale and Megamonas rupellensis, increased in the NAFLD group. Furthermore, the genus Megamonas was enriched in the NAFLD_AW group, while Odoribacter, Alistipes, Dialister, and Akkermansia were depleted compared with the Ctrl_Lean or Ctrl_AW group at the genus level. Megamonas hypermegale and Megamonas rupellensis exhibited a significant increase in NAFLD_AW children compared with the Ctrl_Lean or Ctrl_AW group at the species level. Compared with healthy children, the pathways of P461-PWY contributed by the genus Megamonas were significantly increased in NAFLD_AW. We found that compared to healthy children, the genus Megamonas was enriched, while Megamonas hypermegale and Megamonas rupellensis were enriched at the species level in children and adolescents with NAFLD. This indicates that the NAFLD status and/or diet associated with NAFLD patients might lead to the enrichment of the genus Megamonas or Megamonas species.
Topics: Humans; Adolescent; Child; Non-alcoholic Fatty Liver Disease; Gastrointestinal Microbiome; Firmicutes; Liver
PubMed: 36539432
DOI: 10.1038/s41598-022-25140-2 -
Microbiology Resource Announcements Apr 2020We announce the complete genome sequence of JCM 14723 (YIT 11815). The genome consists of a circular chromosome (2,522,577 bp, 31.5% G+C content) and a plasmid of...
We announce the complete genome sequence of JCM 14723 (YIT 11815). The genome consists of a circular chromosome (2,522,577 bp, 31.5% G+C content) and a plasmid of 46,189 bp (29.4% G+C content). The genome was predicted to contain 6 rRNA operons, 53 tRNA genes, and 2,440 protein-coding sequences.
PubMed: 32299874
DOI: 10.1128/MRA.00142-20 -
Nutrients Apr 2023The etiology of systemic lupus erythematosus (SLE) remains unclear, with both genetic and environmental factors potentially contributing. This study aimed to explore the...
The etiology of systemic lupus erythematosus (SLE) remains unclear, with both genetic and environmental factors potentially contributing. This study aimed to explore the relationship among gut microbiota (GM), intestinal permeability, and food intake with inflammatory markers in inactive SLE patients. A total of 22 women with inactive SLE and 20 healthy volunteers were enrolled, and dietary intake was assessed through 24-h dietary recalls. Plasma zonulin was used to evaluate intestinal permeability, while GM was determined by 16S rRNA sequencing. Regression models were used to analyze laboratory markers of lupus disease (C3 and C4 complement and C-reactive protein). Our results showed that the genus Megamonas was significantly enriched in the iSLE group ( < 0.001), with Megamonas funiformis associated with all evaluated laboratory tests ( < 0.05). Plasma zonulin was associated with C3 levels ( = 0.016), and sodium intake was negatively associated with C3 and C4 levels ( < 0.05). A combined model incorporating variables from each group (GM, intestinal permeability, and food intake) demonstrated a significant association with C3 complement levels ( < 0.01). These findings suggest that increased Megamonas funiformis abundance, elevated plasma zonulin, and higher sodium intake may contribute to reduced C3 complement levels in women with inactive SLE.
Topics: Humans; Female; Complement C3; RNA, Ribosomal, 16S; Lupus Erythematosus, Systemic; Sodium, Dietary
PubMed: 37111218
DOI: 10.3390/nu15081999 -
Microbiology Resource Announcements Dec 2021Here, we report the complete genome sequence of Megamonas funiformis strain 1CBH44, which was isolated from the feces of a healthy Japanese person. The genome consists...
Here, we report the complete genome sequence of Megamonas funiformis strain 1CBH44, which was isolated from the feces of a healthy Japanese person. The genome consists of a circular chromosome (2,310,709 bp, with a GC content of 31.5%) and possesses 2,170 putative protein-coding genes, 18 rRNA genes, and 54 tRNA genes.
PubMed: 34854722
DOI: 10.1128/MRA.00785-21 -
Frontiers in Cellular and Infection... 2021The relationship among the gut microbiome, global fecal metabolites and rheumatoid arthritis (RA) has not been systematically evaluated. In this study, we performed 16S...
The relationship among the gut microbiome, global fecal metabolites and rheumatoid arthritis (RA) has not been systematically evaluated. In this study, we performed 16S rDNA sequencing and liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based nontargeted metabolomic profiling on feces of 26 untreated RA patients and 26 healthy controls. Twenty-six genera and forty-one MS2-identified metabolites were significantly altered in the RA patients. , , and were more abundant in the RA patients, while , and were more abundant in the healthy controls. Function prediction analysis demonstrated that the biosynthesis pathways of amino acids, such as L-arginine and aromatic amino acids, were depleted in the RA group. In the metabolome results, fecal metabolites including glycerophospholipids (PC(18:3(9Z,12Z,15Z)/16:1(9Z)), lysoPE 19:1, lysoPE 18:0, lysoPC(18:0/0:0)), sphingolipids (Cer(d18:0/16:0), Cer(d18:0/12:0), Cer(d18:0/14:0)), kynurenic acid, xanthurenic acid and 3-hydroxyanthranilic acid were remarkably altered between the RA patients and healthy controls. Dysregulation of pathways, such as tryptophan metabolism, alpha-linolenic acid metabolism and glycerophospholipid metabolism, may contribute to the development of RA. Additionally, we revealed that the gut microbiome and metabolites were interrelated in the RA patients, while was the core genus. By depicting the overall landscape of the intestinal microbiome and metabolome in RA patients, our study could provide possible novel research directions regarding RA pathogenesis and targeted therapy.
Topics: Arthritis, Rheumatoid; Chromatography, Liquid; Feces; Gastrointestinal Microbiome; Humans; Metabolome; Metabolomics; RNA, Ribosomal, 16S; Tandem Mass Spectrometry
PubMed: 35145919
DOI: 10.3389/fcimb.2021.763507 -
Frontiers in Psychiatry 2019Recently discovered relationships between the gastrointestinal microbiome and the brain have implications for psychiatric disorders, including major depressive disorder...
Recently discovered relationships between the gastrointestinal microbiome and the brain have implications for psychiatric disorders, including major depressive disorder (MDD). Bacterial transplantation from MDD patients to rodents produces depression-like behaviors. In humans, case-control studies have examined the gut microbiome in healthy and affected individuals. We systematically reviewed existing studies comparing gut microbial composition in MDD and healthy volunteers. A PubMed literature search combined the terms "depression," "depressive disorder," "stool," "fecal," "gut," and "microbiome" to identify human case-control studies that investigated relationships between MDD and microbiota quantified from stool. We evaluated the resulting studies, focusing on bacterial taxa that were different between MDD and healthy controls. Six eligible studies were found in which 50 taxa exhibited differences ( < 0.05) between patients with MDD and controls. Patient characteristics and methodologies varied widely between studies. Five phyla-, and -were represented; however, divergent results occurred across studies for all phyla. The largest number of differentiating taxa were within phylum , in which nine families and 12 genera differentiated the diagnostic groups. The majority of these families and genera were found to be statistically different between the two groups in two identified studies. Family differentiated the diagnostic groups in four studies (with an even split in directionality). Across all five phyla, nine genera were higher in MDD (, and ), six were lower (, and ), and six were divergent (, and ). We highlight mechanisms and products of bacterial metabolism as they may relate to the etiology of depression. No consensus has emerged from existing human studies of depression and gut microbiome concerning which bacterial taxa are most relevant to depression. This may in part be due to differences in study design. Given that bacterial functions are conserved across taxonomic groups, we propose that studying microbial functioning may be more productive than a purely taxonomic approach to understanding the gut microbiome in depression.
PubMed: 30804820
DOI: 10.3389/fpsyt.2019.00034 -
Gut Jun 2022The gut microbiota plays a key role in modulating host immune response. We conducted a prospective, observational study to examine gut microbiota composition in... (Observational Study)
Observational Study
OBJECTIVE
The gut microbiota plays a key role in modulating host immune response. We conducted a prospective, observational study to examine gut microbiota composition in association with immune responses and adverse events in adults who have received the inactivated vaccine (CoronaVac; Sinovac) or the mRNA vaccine (BNT162b2; BioNTech; Comirnaty).
DESIGN
We performed shotgun metagenomic sequencing in stool samples of 138 COVID-19 vaccinees (37 CoronaVac and 101 BNT162b2 vaccinees) collected at baseline and 1 month after second dose of vaccination. Immune markers were measured by SARS-CoV-2 surrogate virus neutralisation test and spike receptor-binding domain IgG ELISA.
RESULTS
We found a significantly lower immune response in recipients of CoronaVac than BNT162b2 vaccines (p<0.05). was persistently higher in subjects with high neutralising antibodies to CoronaVac vaccine (p=0.023) and their baseline gut microbiome was enriched in pathways related to carbohydrate metabolism (linear discriminant analysis (LDA) scores >2 and p<0.05). Neutralising antibodies in BNT162b2 vaccinees showed a positive correlation with the total abundance of bacteria with flagella and fimbriae including (p=0.028). The abundance of and two species were enriched in individuals with fewer adverse events following either of the vaccines indicating that these bacteria may play an anti-inflammatory role in host immune response (LDA scores>3 and p<0.05).
CONCLUSION
Our study has identified specific gut microbiota markers in association with improved immune response and reduced adverse events following COVID-19 vaccines. Microbiota-targeted interventions have the potential to complement effectiveness of COVID-19 vaccines.
Topics: Adult; Antibodies, Neutralizing; Antibodies, Viral; BNT162 Vaccine; COVID-19; COVID-19 Vaccines; Gastrointestinal Microbiome; Humans; Immunogenicity, Vaccine; Prospective Studies; SARS-CoV-2; Vaccines, Synthetic; mRNA Vaccines
PubMed: 35140064
DOI: 10.1136/gutjnl-2021-326563 -
Journal of Cachexia, Sarcopenia and... Dec 2021Cancer cachexia is characterized by a negative energy balance, muscle and adipose tissue wasting, insulin resistance, and systemic inflammation. Because of its strong...
BACKGROUND
Cancer cachexia is characterized by a negative energy balance, muscle and adipose tissue wasting, insulin resistance, and systemic inflammation. Because of its strong negative impact on prognosis and its multifactorial nature that is still not fully understood, cachexia remains an important challenge in the field of cancer treatment. Recent animal studies indicate that the gut microbiota is involved in the pathogenesis and manifestation of cancer cachexia, but human data are lacking. The present study investigates gut microbiota composition, short-chain fatty acids (SCFA), and inflammatory parameters in human cancer cachexia.
METHODS
Faecal samples were prospectively collected in patients (N = 107) with pancreatic cancer, lung cancer, breast cancer, or ovarian cancer. Household partners (N = 76) of the patients were included as healthy controls with similar diet and environmental conditions. Patients were classified as cachectic if they lost >5% body weight in the last 6 months. Gut microbiota composition was analysed by sequencing of the 16S rRNA V4 gene region. Faecal SCFA levels were quantified by gas chromatography. Faecal calprotectin was assessed with enzyme-linked immunosorbent assay. Serum C-reactive protein and leucocyte counts were retrieved from medical records.
RESULTS
Cachexia prevalence was highest in pancreatic cancer (66.7%), followed by ovarian cancer (25%), lung cancer (20.8%), and breast cancer (17.3%). Microbial α-diversity was not significantly different between cachectic cancer patients (N = 33), non-cachectic cancer patients (N = 74), or healthy controls (N = 76) (species richness P = 0.31; Shannon effective index P = 0.46). Community structure (β-diversity) tended to differ between these groups (P = 0.053), although overall differences were subtle and no clear clustering of samples was observed. Proteobacteria (P < 0.001), an unknown genus from the Enterobacteriaceae family (P < 0.01), and Veillonella (P < 0.001) were more abundant among cachectic cancer patients. Megamonas (P < 0.05) and Peptococcus (P < 0.001) also showed differential abundance. Faecal levels of all SCFA tended to be lower in cachectic cancer patients, but only acetate concentrations were significantly reduced (P < 0.05). Faecal calprotectin levels were positively correlated with the abundance of Peptococcus, unknown Enterobacteriaceae, and Veillonella. We also identified several correlations and interactions between clinical and microbial parameters.
CONCLUSIONS
This clinical study provided the first insights into the alterations of gut microbiota composition and SCFA levels that occur in cachectic cancer patients and how they are related to inflammatory parameters. These results pave the way for further research examining the role of the gut microbiota in cancer cachexia and its potential use as therapeutic target.
Topics: Animals; Cachexia; Fatty Acids, Volatile; Gastrointestinal Microbiome; Humans; Pancreatic Neoplasms; RNA, Ribosomal, 16S
PubMed: 34609073
DOI: 10.1002/jcsm.12804 -
International Journal of Systematic and... Dec 2008We report here the identification, characterization and culture of a Gram-negative to Gram-variable, rod-shaped, non-spore-forming anaerobic bacterium (strain FM1025(T))...
We report here the identification, characterization and culture of a Gram-negative to Gram-variable, rod-shaped, non-spore-forming anaerobic bacterium (strain FM1025(T)) isolated from the caecum of a duck. Phylogenetic analysis based on comparative 16S rRNA gene sequencing showed that this strain clustered with species of the family 'Acidaminococcaceae', with 94.9 % similarity to Megamonas hypermegale DSM 1672(T) and less than 91 % similarity with type strains of Pectinatus species. Sequence similarities of at least 98-99 % were observed with numerous sequences deposited in GenBank of uncultured strains from human and chicken caecal contents, but this strain is the first isolate of this taxon to be cultivated and described. On the basis of morphological, physiological and phylogenetic features, this strain should be assigned to a novel species in the genus Megamonas, for which the name Megamonas rupellensis sp. nov. is proposed. The type strain is strain FM1025(T) (=DSM 19944(T) =CIP 109788(T)).
Topics: Anaerobiosis; Animals; Cecum; Ducks; Microscopy, Electron, Scanning; Molecular Sequence Data; Phylogeny; RNA, Ribosomal, 16S; Species Specificity; Veillonellaceae
PubMed: 19060083
DOI: 10.1099/ijs.0.2008/001297-0