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Gut Mar 2020The significance of the liver-microbiome axis has been increasingly recognised as a major modulator of autoimmunity. The aim of this study was to take advantage of a...
OBJECTIVE
The significance of the liver-microbiome axis has been increasingly recognised as a major modulator of autoimmunity. The aim of this study was to take advantage of a large well-defined corticosteroids treatment-naïve group of patients with autoimmune hepatitis (AIH) to rigorously characterise gut dysbiosis compared with healthy controls.
DESIGN
We performed a cross-sectional study of individuals with AIH (n=91) and matched healthy controls (n=98) by 16S rRNA gene sequencing. An independent cohort of 28 patients and 34 controls was analysed to validate the results. All the patients were collected before corticosteroids therapy.
RESULTS
The gut microbiome of steroid treatment-naïve AIH was characterised with lower alpha-diversity (Shannon and observed operational taxonomic units, both p<0.01) and distinct overall microbial composition compared with healthy controls (p=0.002). Depletion of obligate anaerobes and expansion of potential pathobionts including were associated with disease status. Of note, , the most strongly disease-associated taxa (p=8.85E-8), positively correlated with serum level of aspartate aminotransferase and liver inflammation. Furthermore, the combination of four patients with AIH-associated genera distinguished AIH from controls with an area under curves of approximately 0.8 in both exploration and validation cohorts. In addition, multiple predicted functional modules were altered in the AIH gut microbiome, including lipopolysaccharide biosynthesis as well as metabolism of amino acids that can be processed by bacteria to produce immunomodulatory metabolites.
CONCLUSION
Our study establishes compositional and functional alterations of gut microbiome in AIH and suggests the potential for using gut microbiota as non-invasive biomarkers to assess disease activity.
Topics: Adolescent; Adult; Aged; Aspartate Aminotransferases; Case-Control Studies; Clostridiales; Cross-Sectional Studies; Dysbiosis; Female; Gastrointestinal Microbiome; Hepatitis, Autoimmune; Humans; Lactobacillus; Male; Middle Aged; Severity of Illness Index; Veillonella; Young Adult
PubMed: 31201284
DOI: 10.1136/gutjnl-2018-317836 -
BJOG : An International Journal of... Jan 2020To evaluate the potential impact of intrapartum antibiotics, and their specific classes, on the infant gut microbiota in the first year of life.
OBJECTIVE
To evaluate the potential impact of intrapartum antibiotics, and their specific classes, on the infant gut microbiota in the first year of life.
DESIGN
Prospective study of infants in the New Hampshire Birth Cohort Study (NHBCS).
SETTINGS
Rural New Hampshire, USA.
POPULATION OR SAMPLE
Two hundred and sixty-six full-term infants from the NHBCS.
METHODS
Intrapartum antibiotic use during labour and delivery was abstracted from medical records. Faecal samples collected at 6 weeks and 1 year of age were characterised by 16S rRNA sequencing, and metagenomics analysis in a subset of samples.
EXPOSURES
Maternal exposure to antibiotics during labour and delivery.
MAIN OUTCOME MEASURE
Taxonomic and functional profiles of faecal samples.
RESULTS
Infant exposure to intrapartum antibiotics, particularly to two or more antibiotic classes, was independently associated with lower microbial diversity scores as well as a unique bacterial community at 6 weeks (GUnifrac, P = 0.02). At 1 year, infants in the penicillin-only group had significantly lower α diversity scores than infants not exposed to intrapartum antibiotics. Within the first year of life, intrapartum exposure to penicillins was related to a significantly lower increase in several taxa including Bacteroides, use of cephalosporins was associated with a significantly lower rise over time in Bifidobacterium and infants in the multi-class group experienced a significantly higher increase in Veillonella dispar.
CONCLUSIONS
Our findings suggest that intrapartum antibiotics alter the developmental trajectory of the infant gut microbiome, and specific antibiotic types may impact community composition, diversity and keystone immune training taxa.
TWEETABLE ABSTRACT
Class of intrapartum antibiotics administered during delivery relates to maturation of infant gut microbiota.
Topics: Antibiotic Prophylaxis; Bacteroides; Bacteroidetes; Bifidobacterium; Feces; Female; Gastrointestinal Microbiome; Humans; Infant, Newborn; Lactobacillus; Maternal Exposure; Mothers; Pregnancy; Prospective Studies; RNA, Ribosomal, 16S; Sequence Analysis, RNA; Term Birth; Vagina; beta-Lactamases
PubMed: 31006170
DOI: 10.1111/1471-0528.15799 -
Clinical Oral Investigations Nov 2019To identify the microbiome in sockets with alveolar osteitis and compare it with a control group using metagenomic techniques.
OBJECTIVE
To identify the microbiome in sockets with alveolar osteitis and compare it with a control group using metagenomic techniques.
MATERIALS AND METHODS
A case-control study was conducted in subjects that had undergone a tooth extraction. Microbiological samples were taken from the sockets of 10 patients with dry socket after tooth extraction (AO group) and 10 patients in whom exodontia resulted in no postoperative complications (control group). Bacterial DNA was isolated, and the 16S rRNA gene was amplified and sequenced. Multiplexed tag-encoded sequencing of DNA from the samples was performed, and the reads were processed by Metagenomic Rapid Annotation.
RESULTS
A total of 151 different species were found: 55 bacteria were only found in the AO group, 51 were specific to the control group, and 45 were common to both groups. The most frequently found genera in both groups were Prevotella. Prevotella nanceiensis, Actinomyces odontolyticus, Treponema maltophilum, Veillonella dispar, Tannerella forsythia, and Leuconostoc mesenteroides were found in several patients with alveolar osteitis, with an abundance greater than 0.5%, and were absent in all the control group samples.
CONCLUSIONS
Patients who develop alveolar osteitis after dental extractions might have a different microbiota from that of patients without postoperative complications. Since this is a preliminary report, further research is needed to assess whether bacteria play an important role in the etiology of dry socket.
CLINICAL RELEVANCE
This study seems to indicate that bacteria may play an important role in the alveolar osteitis etiology. Thus, new prevention and treatment strategies should be considered.
Topics: Bacteria; Case-Control Studies; Dry Socket; Female; Humans; Male; Metagenome; RNA, Ribosomal, 16S; Tooth Extraction
PubMed: 30937543
DOI: 10.1007/s00784-019-02855-7 -
International Journal of Obesity (2005) Jan 2020Mother-to-newborn transmission of obesity-associated microbiota may be modified by birth mode (vaginal vs. Cesarean delivery). Prospective data to test this hypothesis...
BACKGROUND
Mother-to-newborn transmission of obesity-associated microbiota may be modified by birth mode (vaginal vs. Cesarean delivery). Prospective data to test this hypothesis are still sparse.
OBJECTIVE
To examine prospective associations of maternal pre-pregnancy BMI and gestational weight gain with the infant gut microbiome by birth-mode strata.
SUBJECTS/METHODS
In 335 mother-infant pairs in the New Hampshire Birth Cohort, we ascertained data from questionnaires and medical records, and generated microbiome data from 6-week-old infants' stool using Illumina 16s rRNA gene sequencing (V4-V5 region). Analyses were stratified by birth mode and conducted before and after adjusting for potential confounders, which included maternal age, education, parity, and Mediterranean diet score.
RESULTS
Among 335 mothers, 56% had normal pre-pregnancy BMI ( < 25, referent), 27% were overweight (BMI 25-30), and 18% obese (BMI > 30). Among the 312 mothers with weight gain data, 10% had inadequate weight gain, 30% adequate (referent), and 60% excess. Birth mode modified associations of pre-pregnancy BMI with several genera, including the most abundant genus, Bacteroides (P for interaction = 0.05). In the vaginal-delivery group, maternal overweight or obesity was associated with higher infant gut microbiome diversity and higher relative abundance of 15 operational taxonomic units (OTUs), including overrepresentation of Bacteroides fragilis, Escherichia coli, Veillonella dispar, and OTUs in the genera Staphylococcus and Enterococcus. In the Cesarean-delivered group, there were no significant associations of pre-pregnancy BMI with infant microbiome (alpha) diversity or OTUs. Gestational weight gain was not associated with differential relative abundance of infant gut microbial OTUs or with measures of microbial diversity in infants delivered vaginally or by Cesarean section.
CONCLUSIONS
Among vaginally-delivered infants, maternal overweight and obesity was associated with altered infant gut microbiome composition and higher diversity. These associations were not observed in Cesarean-delivered infants, whose microbiome development differs from vaginally-delivered infants. Our study provides additional evidence of birth-mode dependent associations of maternal body weight status with the infant gut microbiota. The role of these associations in mediating the intergenerational cycle of obesity warrants further examination.
Topics: Adult; Bacteria; Body Mass Index; Body Weight; Delivery, Obstetric; Feces; Female; Gastrointestinal Microbiome; Gestational Weight Gain; Humans; Infant; Male; Pregnancy; Prospective Studies
PubMed: 30765892
DOI: 10.1038/s41366-018-0273-0 -
Singapore Medical Journal Oct 2019The objectives of this study were to examine the effects of ethnicity, gender and a proton pump inhibitor (PPI), omeprazole, on the human gut microbiome. PPIs are... (Comparative Study)
Comparative Study
INTRODUCTION
The objectives of this study were to examine the effects of ethnicity, gender and a proton pump inhibitor (PPI), omeprazole, on the human gut microbiome. PPIs are commonly used for the treatment of acid-related disorders. We hypothesised that PPI therapy might perturb microbial communities and alter the gut microbiome.
METHODS
Healthy subjects of Chinese (n = 12), Malay (n = 12) and Indian (n = 10) ancestry, aged 21-37 years, were enrolled. They provided a baseline stool sample (Day 1) and were then given a course of omeprazole at therapeutic dose (20 mg daily) for seven days. Stool samples were collected again on Day 7 and 14 (one week after stopping omeprazole). Microbial DNA was extracted from the stool samples, followed by polymerase chain reaction, library construction, 16S rRNA sequencing using Illumina MiSeq, and statistical and bioinformatics analyses.
RESULTS
The findings showed an increase in species richness (p = 0.018) after omeprazole consumption on Day 7, which reverted to baseline on Day 14. There were significant increases in the relative abundance of Streptococcus vestibularis (p = 0.0001) and Veillonella dispar (p = 0.0001) on Day 7, which diminished on Day 14. Faecalibacterium prausnitzii, Sutterella stercoricanis and Bacteroides denticanum were characteristic of Chinese, Malays and Indians, respectively. Lactobacillaceae and Bacteroides xylanisolvens were the signature taxa of male and female subjects, respectively.
CONCLUSION
The study demonstrated alterations in the gut microbiome following omeprazole treatment. This may explain the underlying pathology of increased risk of Clostridium difficile infections associated with omeprazole therapy.
Topics: Adult; Bacillus; China; Ethnicity; Feces; Female; Gastrointestinal Microbiome; Humans; India; Malaysia; Male; Omeprazole; Proton Pump Inhibitors; Singapore; Young Adult
PubMed: 30488079
DOI: 10.11622/smedj.2018152