Circulating bacterial signature is linked to metabolic disease and shifts with metabolic alleviation after bariatric surgery

Abstract Background The microbiome has emerged as an environmental factor contributing to obesity and type 2 diabetes (T2D). Increasing evidence suggests links between circulating bacterial components (i.e., bacterial DNA), cardiometabolic disease, and blunted response to metabolic interventions. In this aspect, thorough next-generation sequencing-based and contaminant-aware approaches are lacking. To address this, we tested whether bacterial DNA could be amplified in the blood of subjects with obesity and high metabolic risk under strict experimental and analytical control and whether a putative bacterial signature is related to metabolic improvement after bariatric surgery. Methods Subjects undergoing bariatric surgery were recruited into sex- and BMI-matched subgroups with (n = 24) or without T2D (n = 24). Bacterial DNA in the blood was quantified and prokaryotic 16S rRNA gene amplicons were sequenced. A contaminant-aware approach was applied to derive a compositional microbial signature from bacterial sequences in all subjects at baseline and at 3 and 12 months after surgery. We modeled associations between bacterial load and composition with host metabolic and anthropometric markers. We further tested whether compositional shifts were related to weight loss response and T2D remission. Lastly, bacteria were visualized in blood samples using catalyzed reporter deposition (CARD)-fluorescence in situ hybridization (FISH). Results The contaminant-aware blood bacterial signature was associated with metabolic health. Based on bacterial phyla and genera detected in the blood samples, a metabolic syndrome classification index score was derived and shown to robustly classify subjects along their actual clinical group. T2D was characterized by decreased bacterial richness and loss of genera associated with improved metabolic health. Weight loss and metabolic improvement following bariatric surgery were associated with an early and stable increase of these genera in parallel with improvements in key cardiometabolic risk parameters. CARD-FISH allowed the detection of living bacteria in blood samples in obesity. Conclusions We show that the circulating bacterial signature reflects metabolic disease and its improvement after bariatric surgery. Our work provides contaminant-aware evidence for the presence of living bacteria in the blood and suggests a putative crosstalk between components of the blood and metabolism in metabolic health regulation.

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Far from the gut but still relevant? Circulating bacterial signature is linked to metabolic disease and shifts with metabolic alleviation after bariatric surgery

10.1101/2021.03.25.21254332 ◽

2021 ◽

Author(s):

Rima M. Chakaroun ◽

Lucas Massier ◽

Anna Heintz-Buschart ◽

Nedal Said ◽

Joerg Fallmann ◽

...

Keyword(s):

Metabolic Disease ◽

Bariatric Surgery ◽

Weight Loss ◽

16S Rrna ◽

Bacterial Load ◽

Metabolic Health ◽

Metabolic Risk ◽

Bacterial Dna ◽

Blood Samples ◽

Living Bacteria

AbstractBackgroundThe microbiome has emerged as an environmental factor contributing to obesity and type 2 diabetes (T2D). While the majority of studies have focused on associations between the gut microbiome and metabolic disease, increasing evidence suggests links between circulating bacterial components (i.e. bacterial DNA) and cardiometabolic disease as well as blunted response to metabolic interventions such as bariatric surgery. In this aspect, thorough next generation sequencing based and contaminant aware approaches are lacking. To address these points, we tested whether bacterial DNA could be amplified in the blood of subjects with obesity and high metabolic risk under strict experimental and analytical control to minimize bacterial contamination. Moreover we characterized a bacterial signature associated with the individual metabolic risk and explored its dynamics alongside metabolic improvement after bariatric surgery.MethodsSubjects undergoing elective bariatric surgery were recruited into sex and BMI matched subgroups with (n=24) or without T2D (n=24). Bacterial DNA in the blood was quantified and prokaryotic 16S rRNA gene amplicons were sequenced. A contaminant aware approach was applied to derive a compositional microbial signature from bacterial sequences in subjects with and without T2D and within subjects at baseline and at three and twelve months post bariatric surgery. We modelled associations between bacterial load and composition with host metabolic and anthropometric markers. We further tested whether compositional shifts were related to weight loss response and T2D remission after bariatric surgery. Lastly, Catalyzed Reporter Deposition (CARD) - Fluorescence In Situ Hybridization (FISH) was employed to visualize bacteria in blood samples.ResultsContaminant aware classification of bacterial 16S rRNA sequences allowed the derivation of a blood bacterial signature, which was associated with metabolic health. Based on bacterial phyla and genera detected in the blood samples, a metabolic syndrome classification index score was derived and shown to robustly classify subjects along their actual clinical group. T2D was characterized by decreased bacterial richness and a loss of genera associated with improved metabolic health. Moreover, circulating bacterial load was significantly associated with metabolic health and increased after bariatric surgery. Weight loss and metabolic improvement following bariatric surgery were associated with an early and stable increase of these genera in parallel with improvements in key cardiometabolic risk parameters. CARD-FISH allowed the detection of living Bacteria in blood samples in obesity.ConclusionsWe show that the circulating bacterial signature reflects metabolic disease and its improvement after bariatric surgery. Our work provides contaminant aware evidence for the presence of living bacteria in the blood and suggests a putative crosstalk between components of the blood and metabolism in metabolic health regulation.

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Comparison of the utility of five commercial kits for extraction of DNA from Aspergillus fumigatus spores.

Acta Biochimica Polonica ◽

10.18388/abp.2010_2445 ◽

2010 ◽

Vol 57 (4) ◽

Cited By ~ 9

Author(s):

Urszula Nawrot ◽

Katarzyna Wlodarczyk ◽

Magdalena Wrobel ◽

Anita Wasik ◽

Tadeusz Dobosz

Keyword(s):

Dna Extraction ◽

Enzymatic Digestion ◽

Cell Disruption ◽

Clinical Samples ◽

Rrna Gene ◽

28S Rrna ◽

Bacterial Dna ◽

Blood Samples ◽

Dna Yield ◽

Commercial Kits

The aim of this study was to compare the efficiency of DNA extraction from water as well as from blood samples spiked with A. fumigatus spores, using selected commercial kits. Extraction of DNA according to manufacturer's protocols was preceded by blood cells lysis and disruption of fungal cells by enzymatic digestion or bead beating. The efficiency of DNA extraction was measured by PCR using Aspergillus-specific primers and SYBR Green I dye or TaqMan probes targeting 28S rRNA gene. All methods allowed the detection of Aspergillus at the lowest tested density of water suspensions of spores (10¹ cells/ml). The highest DNA yield was obtained using the ZR Fungal/Bacterial DNA kit, YeastStar Genomic DNA kit, and QIAamp DNA Mini kit with mechanical cell disruption. The ZR Fungal/Bacterial DNA and YeastStar kits showed the highest sensitivity in examination of blood samples spiked with Aspergillus (100 % for the detection of 10² spores and 75 % for 10¹ spores). Recently, the enzymatic method ceased to be recommended for examination of blood samples for Aspergillus, thus ZR Fungal/Bacterial DNA kit and QIAamp DNA Mini kit with mechanical cell disruption could be used for extraction of Aspergillus DNA from clinical samples.

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Bacterial DNAemia is associated with serum zonulin levels in older subjects

10.1101/2020.04.10.035519 ◽

2020 ◽

Author(s):

Giorgio Gargari ◽

Valentina Taverniti ◽

Cristian Del Bo’ ◽

Stefano Bernardi ◽

Cristina Andres-Lacueva ◽

...

Keyword(s):

16S Rrna ◽

16S Rrna Gene ◽

Serum Levels ◽

Gene Profiling ◽

Rrna Gene ◽

Bacterial Dna ◽

Blood Samples ◽

Gene Copies ◽

Older Subjects ◽

Pcr Targeting

AbstractThe increased presence of bacteria in blood is a plausible contributing factor in the development and progression of aging-associated diseases. In this context, we performed the quantification and the taxonomic profiling of the bacterial DNA in blood samples collected from a group of forty-three older subjects enrolled in a nursing home. Quantitative PCR targeting the 16S rRNA gene revealed that all the older volunteers contained detectable amounts of bacterial DNA in their blood. The total amount of 16S rRNA gene copies varied considerably between subjects. Correlation analyses revealed that the bacterial DNAemia (expressed as concentration of 16S rRNA gene copies in blood) significantly correlated with the serum levels of zonulin, an emerging marker of intestinal permeability. This result was confirmed by the analysis of a second set of blood samples collected after approximately four months from the same subjects. Analyses of 16S rRNA gene profiling revealed that most of the bacterial DNA detected in blood was ascribable to the phylum Proteobacteria with a predominance of Pseudomonadaceae and Enterobacteriaceae. Several control samples were also analyzed to assess the influence exerted by contaminant bacterial DNA potentially originating from reagents and materials. The date reported here suggest that para-cellular permeability of epithelial (and potentially also endothelial) cell layers may play an important role in bacterial migration into the bloodstream. Bacterial DNAemia is likely to impact on several aspects of host physiology and could underpin the development and prognosis of various diseases in older subjects.

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Bacterial DNAemia is associated with serum zonulin levels in older subjects

Scientific Reports ◽

10.1038/s41598-021-90476-0 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Giorgio Gargari ◽

Giacomo Mantegazza ◽

Valentina Taverniti ◽

Cristian Del Bo’ ◽

Stefano Bernardi ◽

...

Keyword(s):

16S Rrna ◽

16S Rrna Gene ◽

Serum Levels ◽

Gene Profiling ◽

Rrna Gene ◽

Bacterial Dna ◽

Blood Samples ◽

Taxonomic Profiling ◽

Older Subjects ◽

Pcr Targeting

AbstractThe increased presence of bacteria in blood is a plausible contributing factor in the development and progression of aging-associated diseases. In this context, we performed the quantification and the taxonomic profiling of the bacterial DNA in blood samples collected from forty-three older subjects enrolled in a nursing home. Quantitative PCR targeting the 16S rRNA gene revealed that all samples contained detectable amounts of bacterial DNA with a concentration that varied considerably between subjects. Correlation analyses revealed that the bacterial DNAemia (expressed as concentration of 16S rRNA gene copies in blood) significantly associated with the serum levels of zonulin, a marker of intestinal permeability. This result was confirmed by the analysis of a second set of blood samples collected from the same subjects. 16S rRNA gene profiling revealed that most of the bacterial DNA detected in blood was ascribable to the phylum Proteobacteria with a predominance of the genus Pseudomonas. Several control samples were also analyzed to assess the influence of contaminant bacterial DNA potentially originating from reagents and materials. The data reported here suggest that para-cellular permeability of epithelial (and, potentially, endothelial) cell layers may play an important role in bacterial migration into the bloodstream. Bacterial DNAemia is likely to impact on several aspects of host physiology and could underpin the development and prognosis of various diseases in older subjects.

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Extraoral Halitosis due to Exhaled Acetone in Patients Undergoing Sleeve Gastrectomy

JOURNAL FOR CLINICAL AND DIAGNOSTIC RESEARCH ◽

10.7860/jcdr/2021/46260.14467 ◽

2021 ◽

Author(s):

Hanadi Alzahrani ◽

Mohammed A AlSarhan ◽

Abdullah Aldohayan ◽

Fahad Bamehriz ◽

Hamad A Alzoman

Keyword(s):

Bariatric Surgery ◽

Weight Loss ◽

Sleeve Gastrectomy ◽

High Rate ◽

Rapid Weight Loss ◽

Gastric Sleeve ◽

Blood Samples ◽

Gastric Sleeve Surgery ◽

The Mean ◽

Breath Acetone

Introduction: Bariatric surgery is widely used and considered as one of the most effective treatments for morbid obesity, but it can be associated with medical and dental adverse side-effects. It is frequently associated with major metabolic changes that may lead to extraoral halitosis. Aim: To assess the role of exhaled acetone produced as a result of weight loss in the production of extra-oral halitosis in patients undergoing bariatric surgery. Materials and Methods: A prospective longitudinal cohort study was designed from October 2018 to November 2019 and monitored for six months postsurgery. The subjects were patients undergoing sleeve gastrectomy surgery with a Body Mass Index (BMI) of 35-50 kg/m2. Subjects were divided into two groups of low BMI loss (<5 Kg/m2) and high BMI loss (≥5 Kg/m2) postsurgery, Breath samples were collected with a portable breath ketone analyser for measurement of acetone concentrations, and blood samples were taken for measurement of 3-hydroxybutyrate levels. Breath and blood samples were taken at baseline then at one month, three months, and six months postsurgery. All statistical analysis were performed using the SPSS version 22.0 with a significance value of p-value set at p<0.05. Results: Out of 43 patients enrolled initially, eventually 39 patients completed the study. The mean level of breath acetone was 4.1, 3.4, and 3.8 ppm at one month, three months, and six months, respectively (p=0.018). There was a statistically significant increase in breath acetone at one month in patients with a high rate of BMI loss. At one month, the mean blood level of 3-hydroxybutyrate was higher in patients with a high rate of BMI loss than in those with a low rate of BMI loss (1.9 vs. 1.2 mmol/L; p=0.049). The levels of breath acetone and blood 3-hydroxybutyrate were significantly correlated at one month (r=0.6, p<0.05). Conclusion: Rapid weight loss one month after gastric sleeve surgery resulted in high acetone levels suggestive of increased extraoral halitosis in such patients. Increased Acetone levels in breath and 3-hydroxybutyrate in blood are suggestive of increased extraoral halitosis in patients undergoing gastric sleeve surgery particularly within a month after surgery.

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Distinct patterns in the gut microbiota after surgical or medical therapy in obese patients

PeerJ ◽

10.7717/peerj.3443 ◽

2017 ◽

Vol 5 ◽

pp. e3443 ◽

Cited By ~ 41

Author(s):

Daniel A. Medina ◽

Juan P. Pedreros ◽

Dannae Turiel ◽

Nicolas Quezada ◽

Fernando Pimentel ◽

...

Keyword(s):

Bariatric Surgery ◽

Weight Loss ◽

Gut Microbiota ◽

Surgical Procedures ◽

Weight Loss Surgery ◽

Dietary Treatment ◽

16S Rrna Gene Sequencing ◽

Health Improvement ◽

Rrna Gene ◽

The Impact

Bariatric surgery is highly successful in improving health compared to conventional dietary treatments. It has been suggested that the gut microbiota is a relevant factor in weight loss after bariatric surgery. Considering that bariatric procedures cause different rearrangements of the digestive tract, they probably have different effects on the gut microbiota. In this study, we compared the impact of medical treatment, sleeve gastrectomy and Roux-en-Y gastric bypass on the gut microbiota from obese subjects. Anthropometric and clinical parameters were registered before, 6 and 12 months after treatment. Fecal samples were collected and microbiota composition was studied before and six months post treatment using 16S rRNA gene sequencing and qPCR. In comparison to dietary treatment, changes in intestinal microbiota were more pronounced in patients subjected to surgery, observing a bloom inProteobacteria. Interestingly,Bacteroidetesabundance was largely different after six months of each surgical procedure. Furthermore, changes in weight and BMI, or glucose metabolism, correlated positively with changes in these two phyla in these surgical procedures. These results indicate that distinct surgical procedures alter the gut microbiota differently, and changes in gut microbiota might contribute to health improvement. This study contributes to our understanding of the impact of weight loss surgery on the gut microbiota, and could be used to replicate this effect using targeted therapies.

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