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Atherosclerosis May 2019Although most risk factors for cardiac valve calcification (VC) are similar to those for coronary artery disease (CAD), they differ regarding lesions and clinical... (Comparative Study)
Comparative Study
BACKGROUND AND AIMS
Although most risk factors for cardiac valve calcification (VC) are similar to those for coronary artery disease (CAD), they differ regarding lesions and clinical symptoms. Recently, increasing evidence suggests that intestinal bacteria play essential roles in cardiovascular disease (CVD). It is plausible that the gut microbiota is linked to the occurrence of different CVDs under similar risk factors. Thus, we aimed to explore the gut microbiomes in patients with VC or CAD and determine their underlying connections.
METHODS
We collected samples from 119 subjects and performed 16S rRNA gene sequencing to analyze the gut microbiomes in VC and CAD patients and in control volunteers.
RESULTS
The gut microbiomes of VC and CAD patients were significantly different in terms of beta-diversity. Bacteria from Veillonella dispar, Bacteroides plebeius and Fusobacterium were enriched in the VC group, while members of Collinsella aerofaciens, Megamonas, Enterococcus, Megasphaera, Dorea and Blautia were decreased. According to the association with dyslipidemia, seven operational taxonomic units (OTUs), including Parabacteroides distasonis, Megamonas, Fusobacterium, Bacteroides sp., Bacteroides plebeius, Lactobacillus and Prevotella copri, were regarded as potential pathogens for CVDs. Additionally, Prevotella copri might be a keystone of CVDs, especially in VC patients, while Collinsella aerofaciens is a possible keystone of CAD, based on the multi-correlations of these bacteria with other OTUs in microbial communities.
CONCLUSIONS
Patients with VC and CAD suffer from different gut microbial dysbiosis. The gut microbiomes are associated with the clinical characteristics in these diseases and might be potential therapeutic targets.
Topics: Adult; Aged; Calcinosis; Coronary Artery Disease; Dysbiosis; Female; Gastrointestinal Microbiome; Heart Valve Diseases; Humans; Male; Middle Aged
PubMed: 30897381
DOI: 10.1016/j.atherosclerosis.2018.11.038 -
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 -
PloS One 2018We investigated the association between bacterial microbiota in breast milk and the infant mouth. The influence of human papilloma virus (HPV) infection on infant oral...
OBJECTIVE
We investigated the association between bacterial microbiota in breast milk and the infant mouth. The influence of human papilloma virus (HPV) infection on infant oral microbiota was also assessed.
MATERIAL AND METHODS
Altogether 35 breast milk and 35 infant oral samples with known HPV status were selected from the Finnish Family HPV Study cohort. In total, there were 31 mother-infant pairs. The microbiota composition was characterized by 16S rRNA gene sequencing (V3-V4 region).
RESULTS
HPV DNA was present in 8.6% (3/35) of the breast milk and 40% (14/35) of the infant oral samples. Eight shared genera between breast milk and infant oral were found; these included Streptococcus, Staphylococcus, Unclassified Gemellaceae, Rothia, Veillonella, Haemophilus, Propionibacterium and Corynebacterium. HPV status was not associated with either microbiota richness or diversity in the infant mouth. However, the infant oral microbiota clustered in different groups according to HPV status. We detected higher abundance of Veillonella dispar (p = 0.048) at species level in HPV negative infant oral samples. We did not detect differences in the breast milk microbiota composition related to HPV infection due to only three HPV positive milk samples.
CONCLUSIONS
HPV infection is associated with distinct oral bacterial microbiota composition in infants. The direction of causality underlying the phenomenon remains unclear.
Topics: Bacteria; Biodiversity; Cohort Studies; Discriminant Analysis; Female; Finland; Genotype; Humans; Infant; Infant, Newborn; Male; Microbiota; Milk, Human; Mouth Mucosa; Papillomaviridae; Papillomavirus Infections; Principal Component Analysis; RNA, Ribosomal, 16S; Sequence Analysis, DNA; Veillonella
PubMed: 30395655
DOI: 10.1371/journal.pone.0207016 -
Scientific Reports Sep 2018Human intestinal microbes can mediate development of arthritis - Studies indicate that certain bacterial nucleic acids may exist in synovial fluid (SF) and could be...
Human intestinal microbes can mediate development of arthritis - Studies indicate that certain bacterial nucleic acids may exist in synovial fluid (SF) and could be involved in arthritis, although the underlying mechanism remains unclear. To characterize potential SF bacterial nucleic acids, we used 16S rRNA gene amplicon sequencing to assess bacterial nucleic acid communities in 15 synovial tissue (ST) and 110 SF samples from 125 patients with rheumatoid arthritis (RA) and 16 ST and 42 SF samples from 58 patients with osteoarthritis (OA). Our results showed an abundant diversity of bacterial nucleic acids in these clinical samples, including presence of Porphyromonas and Bacteroides in all 183 samples. Agrobacterium, Comamonas, Kocuria, Meiothermus, and Rhodoplanes were more abundant in synovial tissues of rheumatoid arthritis (STRA). Atopobium, Phascolarctobacterium, Rhodotorula mucilaginosa, Bacteroides uniformis, Rothia, Megasphaera, Turicibacter, Leptotrichia, Haemophilus parainfluenzae, Bacteroides fragilis, Porphyromonas, and Streptococcus were more abundant in synovial tissues of osteoarthritis (STOA). Veillonella dispar, Haemophilus parainfluenzae, Prevotella copri and Treponema amylovorum were more abundant in synovial fluid of rheumatoid arthritis (SFRA), while Bacteroides caccae was more abundant in the synovial fluid of osteoarthritis (SFOA). Overall, this study confirms existence of bacterial nucleic acids in SF and ST samples of RA and OA lesions and reveals potential correlations with degree of disease.
Topics: Adult; Algorithms; Arthritis, Rheumatoid; Bacteria; Cytokines; Discriminant Analysis; Humans; Microbiota; Nucleic Acids; Osteoarthritis; Principal Component Analysis; Synovial Fluid; Synovial Membrane
PubMed: 30250232
DOI: 10.1038/s41598-018-32675-w -
Frontiers in Microbiology 2018The purpose of this study was to investigate strain dependent differences of the cariogenic biofilm forming within both simple and complex communities. A mono-species...
The purpose of this study was to investigate strain dependent differences of the cariogenic biofilm forming within both simple and complex communities. A mono-species containing representative clinical isolates (caries and non-caries), and a multispecies caries biofilm model containing , , and , and either of two representative clinical isolates (caries and non-caries), was developed as a comparison model. Compositional analysis of total and live bacteria within biofilms, and transcriptional analysis of biofilm associated virulence factors were evaluated by live/dead PCR and quantitative PCR, respectively. Scanning electron microscopy (SEM) was used to analyze the architecture of biofilm. One-way analysis of variance and -tests were used to investigate significant differences between independent groups of data. Within a mono-species biofilm, different strains responded similarly to one another during biofilm formation in different carbohydrate sources, with sucrose showing the highest levels of biofilm biomass and galactose showing the lowest. Within the polymicrobial biofilm system, compositional analysis of the bacteria within the biofilm showed that derived from a caries-free patient was preferentially composed of both total and viable , whereas derived from a caries patient was dominated by both total and viable ( < 0.001). Normalized gene expression analysis of , , , , , and , showed a general upregulation within the dominant biofilm. We were able to demonstrate that individual strains derived from different patients exhibited altered biofilm characteristics, which were not obvious within a simple mono-species biofilm model. Influencing the environmental conditions changed the composition and functionality within the polymicrobial biofilm. The biofilm model described herein provides a novel and reproducible method of assessing the impact on the biofilm microbiome upon different environmental influences.
PubMed: 30083138
DOI: 10.3389/fmicb.2018.01498 -
Frontiers in Microbiology 2018Colorectal cancer (CRC) is the third most diagnosed cancer worldwide due to its high difficulty in early diagnosis, high mortality rate and short life span. Recent...
Colorectal cancer (CRC) is the third most diagnosed cancer worldwide due to its high difficulty in early diagnosis, high mortality rate and short life span. Recent publications have demonstrated the involvement of the commensal gut microbiota in the initiation, progression and chemoresistance of CRC. However, this microbial community has not been explored within CRC patients after anti-cancer treatments. To this end, we performed next generation sequencing-based metagenomic analysis to determine the composition of the microbiota in CRC patients after anti-cancer treatments. The microbial 16S rRNA genes were analyzed from a total of 69 fecal samples from four clinical groups, including healthy individuals, CRC patients, and CRC patients treated with surgery or chemotherapy. The findings suggested that surgery greatly reduced the bacterial diversity of the microbiota in CRC patients. Moreover, were shown to confer chemoresistance during CRC therapy, and certain bacterial strains or genera, such as the genus and species , were specifically associated with CRC patients who were treated with chemotherapeutic cocktails, suggesting their potential relationships with chemoresistance. These candidate bacterial genera or strains may have the ability to enhance the dosage response to conventional chemotherapeutic cocktails or reduce the side effects of these cocktails. A combination of common CRC risk factors, such as age, gender and BMI, identified in this study improved our understanding of the microbial community and its compositional variation during anti-cancer treatments. However, the underlying mechanisms of these microbial candidates remain to be investigated in animal models. Taken together, the findings of this study indicate that fecal microbiome-based approaches may provide additional methods for monitoring and optimizing anti-cancer treatments.
PubMed: 30065719
DOI: 10.3389/fmicb.2018.01607 -
NPJ Biofilms and Microbiomes 2018is a Gram-negative organism, strongly associated with aggressive forms of periodontitis. An important virulence property of is its ability to form tenacious biofilms...
is a Gram-negative organism, strongly associated with aggressive forms of periodontitis. An important virulence property of is its ability to form tenacious biofilms that can attach to abiotic as well as biotic surfaces. The histone-like (H-NS) family of nucleoid-structuring proteins act as transcriptional silencers in many Gram-negative bacteria. To evaluate the role of H-NS in , mutant derivatives of serotype a strain D7S were generated. Characteristics of the mutant phenotype included shorter and fewer pili, and substantially lower monospecies biofilm formation relative to the wild type. Furthermore, the D7S mutant exhibited significantly reduced growth within a seven-species oral biofilm model. However, no apparent difference was observed regarding the numbers and proportions of the remaining six species regardless of being co-cultivated with D7S or its parental strain. Proteomics analysis of the strains grown in monocultures confirmed the role of H-NS as a repressor of gene expression in . Interestingly, proteomics analysis of the multispecies biofilms indicated that the wild type and mutant imposed different regulatory effects on the pattern of protein expression in the other species, i.e., mainly spp., , and . Gene ontology analysis revealed that a large portion of the differentially regulated proteins was related to translational activity. Taken together, our data suggest that, apart from being a negative regulator of protein expression in , H-NS promotes biofilm formation and may be an important factor for survival of this species within a multispecies biofilm.
PubMed: 29844920
DOI: 10.1038/s41522-018-0055-4 -
PloS One 2018Peri-implant infections are the most common cause of implant failure in modern dental implantology. These are caused by the formation of biofilms on the implant surface...
Peri-implant infections are the most common cause of implant failure in modern dental implantology. These are caused by the formation of biofilms on the implant surface and consist of oral commensal and pathogenic bacteria, which harm adjacent soft and hard tissues and may ultimately lead to implant loss. In order to improve the clinical situation, there has to be a better understanding of biofilm formation on abiotic surfaces. Therefore, we successfully developed a system to cultivate an oral multispecies biofilm model in a flow chamber system, optimized for the evaluation of biofilm formation on solid materials by direct microscopic investigation. The model contains four relevant oral bacterial species: Streptococcus oralis, Actinomyces naeslundii, Veillonella dispar and Porphyromonas gingivalis in ratios similar to the native situation. The reliability of the developed "Hanoverian Oral Multispecies Biofilm Implant Flow Chamber" (HOBIC) model was verified. Biofilm volume and live/dead distribution within biofilms were determined by fluorescence staining and confocal laser scanning microcopy (CLSM). The individual species distribution was analyzed using quantitative real time PCR with propidium monoazide pretreatment (PMA-qRT-PCR) and by urea-NaCl fluorescence in situ hybridization (urea-NaCl-FISH). This in vitro model may be used to analyze biofilm formation on dental implants in more detail and to develop future implant systems with improved material properties.
Topics: Bacteria; Bacterial Physiological Phenomena; Biofilms; Humans; Models, Biological; Mouth Mucosa
PubMed: 29771975
DOI: 10.1371/journal.pone.0196967 -
Free Radical Biology & Medicine May 2018Nitric oxide (NO) can be generated endogenously via NO synthases or via the diet following the action of symbiotic nitrate-reducing bacteria in the oral cavity. Given...
Nitric oxide (NO) can be generated endogenously via NO synthases or via the diet following the action of symbiotic nitrate-reducing bacteria in the oral cavity. Given the important role of NO in smooth muscle control there is an intriguing suggestion that cardiovascular homeostasis may be intertwined with the presence of these bacteria. Here, we measured the abundance of nitrate-reducing bacteria in the oral cavity of 25 healthy humans using 16S rRNA sequencing and observed, for 3.5 h, the physiological responses to dietary nitrate ingestion via measurement of blood pressure, and salivary and plasma NO metabolites. We identified 7 species of bacteria previously known to contribute to nitrate-reduction, the most prevalent of which were Prevotella melaninogenica and Veillonella dispar. Following dietary nitrate supplementation, blood pressure was reduced and salivary and plasma nitrate and nitrite increased substantially. We found that the abundance of nitrate-reducing bacteria was associated with the generation of salivary nitrite but not with any other measured variable. To examine the impact of bacterial abundance on pharmacokinetics we also categorised our participants into two groups; those with a higher abundance of nitrate reducing bacteria (> 50%), and those with a lower abundance (< 50%). Salivary nitrite production was lower in participants with lower abundance of bacteria and these individuals also exhibited slower salivary nitrite pharmacokinetics. We therefore show that the rate of nitrate to nitrite reduction in the oral cavity is associated with the abundance of nitrate-reducing bacteria. Nevertheless, higher abundance of these bacteria did not result in an exaggerated plasma nitrite response, the best known marker of NO bioavailability. These data from healthy young adults suggest that the abundance of oral nitrate-reducing bacteria does not influence the generation of NO through the diet, at least when the host has a functional minimum threshold of these microorganisms.
Topics: Adult; Bacteria; Cross-Sectional Studies; Female; Humans; Male; Microbiota; Mouth; Nitrates; Nitric Oxide; Nitrites; Saliva
PubMed: 29550328
DOI: 10.1016/j.freeradbiomed.2018.03.023