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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 -
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 -
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 -
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 -
Microorganisms Aug 2023The aim is better to understand and critically explore and present the available data from observational studies on the pathogenetic role of the microbiome in the... (Review)
Review
The aim is better to understand and critically explore and present the available data from observational studies on the pathogenetic role of the microbiome in the development of rheumatoid arthritis (RA). The electronic databases PubMed, Scopus, and Web of Science were screened for the relevant literature published in the last ten years. The primary outcomes investigated included the influence of the gut microbiome on the pathogenesis and development of rheumatoid arthritis, exploring the changes in microbiota diversity and relative abundance of microbial taxa in individuals with RA and healthy controls (HCs). The risk of bias in the included literature was assessed using the GRADE criteria. Ten observational studies were identified and included in the qualitative assessment. A total of 647 individuals with RA were represented in the literature, in addition to 16 individuals with psoriatic arthritis (PsA) and 247 HCs. The biospecimens comprised fecal samples across all the included literature, with 16S rDNA sequencing representing the primary method of biological analyses. Significant differences were observed in the RA microbiome compared to that of HCs: a decrease in , , , and and increases in , , , , , , and . There are significant alterations in the microbiome of individuals with RA compared to HCs. This includes an increase in and and reductions in . Collectively, these alterations are proposed to induce inflammatory responses and degrade the integrity of the intestinal barrier; however, further studies are needed to confirm this relationship.
PubMed: 37764014
DOI: 10.3390/microorganisms11092170 -
Bidirectional effects of oral anticoagulants on gut microbiota in patients with atrial fibrillation.Frontiers in Cellular and Infection... 2023The imbalance of gut microbiota (GM) is associated with a higher risk of thrombosis in patients with atrial fibrillation (AF). Oral anticoagulants (OACs) have been found...
BACKGROUND
The imbalance of gut microbiota (GM) is associated with a higher risk of thrombosis in patients with atrial fibrillation (AF). Oral anticoagulants (OACs) have been found to significantly reduce the risk of thromboembolism and increase the risk of bleeding. However, the OAC-induced alterations in gut microbiota in patients with AF remain elusive.
METHODS
In this study, the microbial composition in 42 AF patients who received long-term OAC treatment (AF-OAC group), 47 AF patients who did not (AF group), and 40 volunteers with the risk of AF (control group) were analyzed by 16S rRNA gene sequencing of fecal bacterial DNA. The metagenomic functional prediction of major bacterial taxa was performed using the Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) software package.
RESULTS
The gut microbiota differed between the AF-OAC and AF groups. The abundance of and decreased in the two disease groups at the genus level, but OACs treatment mitigated the decreasing tendency and increased beneficial bacterial genera, such as . In addition, OACs reduced the abundance of pro-inflammatory taxa on the genus but increased certain potential pathogenic taxa, such as genera , , and . The Subgroup Linear discriminant analysis effect size (LEfSe) analyses revealed that , , and were more abundant in the anticoagulated bleeding AF patients, and were more abundant in the non-anticoagulated-bleeding-AF patients. The neutrophil-to-lymphocyte ratio (NLR) was lower in the AF-OAC group compared with the AF group ( < 0.05). was positively correlated with the NLR and negatively correlated with the CHA2DS2-VASc score ( < 0.05), and the OACs-enriched species ( and ) was positively correlated with the prothrombin time (PT) ( < 0.05). and were negatively associated with bleeding events ( < 0.05).
CONCLUSIONS
Our study suggested that OACs might benefit AF patients by reducing the inflammatory response and modulating the composition and abundance of gut microbiota. In particular, OACs increased the abundance of some gut microbiota involved in bleeding and gastrointestinal dysfunction indicating that the exogenous supplementation with and might be a prophylactic strategy for AF-OAC patients to lower the risk of bleeding after anticoagulation.
Topics: Humans; Atrial Fibrillation; Gastrointestinal Microbiome; Phylogeny; RNA, Ribosomal, 16S; Stroke; Risk Factors; Anticoagulants; Hemorrhage; Administration, Oral; Risk Assessment
PubMed: 37033478
DOI: 10.3389/fcimb.2023.1038472 -
Journal of Dental Research Jul 2023Ectopic enrichment of oral microbes in the gut is a notable alteration in gut microbial balance. These microbes are likely delivered from the oral cavity with saliva and... (Observational Study)
Observational Study
Ectopic enrichment of oral microbes in the gut is a notable alteration in gut microbial balance. These microbes are likely delivered from the oral cavity with saliva and food; however, evidence of oral-gut microbial transmission is insufficient and needs further investigation. In this observational study, we examined 144 pairs of saliva and stool samples collected from community-dwelling adults to verify the oral-gut microbial link and identify the relevant influencing factors on the increased abundance of oral microbes within the gut. The bacterial composition of each sample was determined using PacBio single-molecule long-read sequencing of the full-length 16S ribosomal RNA gene and amplicon sequence variant (ASV) analysis. Although the bacterial compositions of salivary and gut microbiota were distinctly different, at least 1 ASV was shared between salivary and gut microbiota in 72.9% of subjects. Shared ASVs accounted for 0.0% to 63.1% (median 0.14%) of the gut microbiota in each subject and frequently included abundant and . Their total relative abundance in the gut was significantly higher in older subjects or those with dental plaque accumulation. The gut microbiota with ≥5% of shared ASVs displayed a higher abundance of , , and and a lower abundance of , , , and . Our study presents evidence for the translocation of oral bacteria to the gut in community-dwelling adults and suggests that aging and dental plaque accumulation contribute to an increased abundance of oral microbes in the gut, which might be relevant to the compositional shift in the gut commensals.
Topics: Adult; Humans; Aged; Dental Plaque; Bacteria; Microbiota; Mouth; Gastrointestinal Microbiome; RNA, Ribosomal, 16S
PubMed: 37204134
DOI: 10.1177/00220345231160747 -
Cell Death & Disease Oct 2021Kashin-Beck disease (KBD) is a severe osteochondral disorder that may be driven by the interaction between genetic and environmental factors. We aimed to improve our...
Kashin-Beck disease (KBD) is a severe osteochondral disorder that may be driven by the interaction between genetic and environmental factors. We aimed to improve our understanding of the gut microbiota structure in KBD patients of different grades and the relationship between the gut microbiota and serum metabolites. Fecal and serum samples collected from KBD patients and normal controls (NCs) were used to characterize the gut microbiota using 16S rDNA gene and metabolomic sequencing via liquid chromatography-mass spectrometry (LC/MS). To identify whether gut microbial changes at the species level are associated with the genes or functions of the gut bacteria in the KBD patients, metagenomic sequencing of fecal samples from grade I KBD, grade II KBD and NC subjects was performed. The KBD group was characterized by elevated levels of Fusobacteria and Bacteroidetes. A total of 56 genera were identified to be significantly differentially abundant between the two groups. The genera Alloprevotella, Robinsoniella, Megamonas, and Escherichia_Shigella were more abundant in the KBD group. Consistent with the 16S rDNA analysis at the genus level, most of the differentially abundant species in KBD subjects belonged to the genus Prevotella according to metagenomic sequencing. Serum metabolomic analysis identified some differentially abundant metabolites among the grade I and II KBD and NC groups that were involved in lipid metabolism metabolic networks, such as that for unsaturated fatty acids and glycerophospholipids. Furthermore, we found that these differences in metabolite levels were associated with altered abundances of specific species. Our study provides a comprehensive landscape of the gut microbiota and metabolites in KBD patients and provides substantial evidence of a novel interplay between the gut microbiome and metabolome in KBD pathogenesis.
Topics: Biodiversity; Case-Control Studies; China; Discriminant Analysis; Endemic Diseases; Feces; Gastrointestinal Microbiome; Gene Expression Profiling; Humans; Kashin-Beck Disease; Least-Squares Analysis; Metabolomics; Metagenomics; Osteoarthritis; RNA, Ribosomal, 16S; Risk Assessment
PubMed: 34711812
DOI: 10.1038/s41419-021-04322-2 -
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 -
PloS One 2023The role of bacterial microbiota in the pathogenesis of nontuberculous mycobacterial pulmonary disease (NTM-PD) is unclear. We aimed to compare the bacterial microbiome...
BACKGROUND
The role of bacterial microbiota in the pathogenesis of nontuberculous mycobacterial pulmonary disease (NTM-PD) is unclear. We aimed to compare the bacterial microbiome of disease-invaded lesions and non-invaded lung tissue from NTM-PD patients.
METHODS
We analyzed lung tissues from 23 NTM-PD patients who underwent surgical lung resection. Lung tissues were collected in pairs from each patient, with one sample from a disease-involved site and the other from a non-involved site. Lung tissue microbiome libraries were constructed using 16S rRNA gene sequences (V3-V4 regions).
RESULTS
Sixteen (70%) patients had Mycobacterium avium complex (MAC)-PD, and the remaining seven (30%) had Mycobacterium abscessus-PD. Compared to non-involved sites, involved sites showed greater species richness (ACE, Chao1, and Jackknife analyses, all p = 0.001); greater diversity on the Shannon index (p = 0.007); and genus-level differences (Jensen-Shannon, PERMANOVA p = 0.001). Analysis of taxonomic biomarkers using linear discriminant analysis (LDA) effect sizes (LEfSe) demonstrated that several genera, including Limnohabitans, Rahnella, Lachnospira, Flavobacterium, Megamonas, Gaiella, Subdoligranulum, Rheinheimera, Dorea, Collinsella, and Phascolarctobacterium, had significantly greater abundance in involved sites (LDA >3.00, p <0.05, and q <0.05). In contrast, Acinetobacter had significantly greater abundance at non-involved sites (LDA = 4.27, p<0.001, and q = 0.002). Several genera were differentially distributed between lung tissues from MAC-PD (n = 16) and M. abscessus-PD (n = 7), and between nodular bronchiectatic form (n = 12) and fibrocavitary form (n = 11) patients. However, there was no genus with a significant q-value.
CONCLUSIONS
We identified differential microbial distributions between disease-invaded and normal lung tissues from NTM-PD patients, and microbial diversity was significantly higher in disease-invaded tissues.
TRIAL REGISTRATION
Clinical Trial registration number: NCT00970801.
Topics: Humans; RNA, Ribosomal, 16S; Mycobacterium Infections, Nontuberculous; Mycobacterium avium Complex; Lung Diseases; Lung; Microbiota; Nontuberculous Mycobacteria
PubMed: 37235629
DOI: 10.1371/journal.pone.0285143