Changes in the gut microbiota during and after commercial helium–oxygen saturation diving in China

2019 ◽  
Vol 76 (11) ◽  
pp. 801-807
Author(s):  
Yuan Yuan ◽  
Guosheng Zhao ◽  
Hongwei Ji ◽  
Bin Peng ◽  
Zhiguo Huang ◽  
...  
Keyword(s):  
Gut Microbiota ◽  
Oxygen Saturation ◽  
Amplicon Sequencing ◽  
Obligate Anaerobe ◽  
Sequencing Platform ◽  
Β Diversity ◽  
Faecal Samples ◽  
Increasing Trend ◽  
Hyperbaric Environment ◽  
Illumina Sequencing Platform

ObjectivesThe influence of commercial helium–oxygen saturation diving on divers’ gut microbiotas was assessed to provide dietary suggestion.MethodsFaecal samples of 47 divers working offshore were collected before (T1), during (T2) and after (T3) saturation diving. Their living and excursion depths were 55–134 metres underwater with a saturation duration of 12–31 days and PaO2 of 38–65 kPa. The faecal samples were examined through 16S ribosomal DNA amplicon sequencing based on the Illumina sequencing platform to analyse changes in the bacteria composition in the divers’ guts.ResultsAlthough the α and β diversity of the gut microbiota did not change significantly, we found that living in a hyperbaric environment of helium–oxygen saturation decreased the abundance of the genus Bifidobacterium, an obligate anaerobe, from 2.43%±3.83% at T1 to 0.79%±1.23% at T2 and 0.59%±0.79% at T3. Additionally, the abundance of some short-chain fatty acid (SCFA)-producing bacteria, such as Fusicatenibacter, Faecalibacterium, rectale group and Anaerostipes, showed a decreased trend in the order of before, during and after diving. On the contrary, the abundance of species, such as Lactococcus garvieae, Actinomyces odontolyticus, Peptoclostridium difficile, Butyricimonas virosa, Streptococcus mutans, Porphyromonas asaccharolytica and A. graevenitzii, showed an increasing trend, but most of them were pathogens.ConclusionsOccupational exposure to high pressure in a helium–oxygen saturation environment decreased the abundance of Bifidobacterium and some SCFA-producing bacteria, and increased the risk of pathogenic bacterial infection. Supplementation of the diver diet with probiotics or prebiotics during saturation diving might prevent these undesirable changes.

scholarly journals Conventional myelosuppressive chemotherapy for non-haematological malignancy disrupts the intestinal microbiome

BMC Cancer ◽  
2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Lito E. Papanicolas ◽  
Sarah K. Sims ◽  
Steven L. Taylor ◽  
Sophie J. Miller ◽  
Christos S. Karapetis ◽  
...  
Keyword(s):  
Gut Microbiota ◽  
Relative Abundance ◽  
Haematological Malignancy ◽  
Amplicon Sequencing ◽  
Intestinal Microbiome ◽  
Rrna Gene ◽  
Conventional Chemotherapy ◽  
Myelosuppressive Chemotherapy ◽  
Gram Positive Bacteria ◽  
Faecal Samples

Abstract Background The gut microbiota influences many aspects of host physiology, including immune regulation, and is predictive of outcomes in cancer patients. However, whether conventional myelosuppressive chemotherapy affects the gut microbiota in humans with non-haematological malignancy, independent of antibiotic exposure, is unknown. Methods Faecal samples from 19 participants with non-haematological malignancy, who were receiving conventional chemotherapy regimens but not antibiotics, were examined prior to chemotherapy, 7–12 days after chemotherapy, and at the end of the first cycle of treatment. Gut microbiota diversity and composition was determined by 16S rRNA gene amplicon sequencing. Results Compared to pre-chemotherapy samples, samples collected 7–12 days following chemotherapy exhibited increased richness (mean 120 observed species ± SD 38 vs 134 ± 40; p = 0.007) and diversity (Shannon diversity: mean 6.4 ± 0.43 vs 6.6 ± 0.41; p = 0.02). Composition was significantly altered, with a significant decrease in the relative abundance of gram-positive bacteria in the phylum Firmicutes (pre-chemotherapy median relative abundance [IQR] 0.78 [0.11] vs 0.75 [0.11]; p = 0.003), and an increase in the relative abundance of gram-negative bacteria (Bacteroidetes: median [IQR] 0.16 [0.13] vs 0.21 [0.13]; p = 0.01 and Proteobacteria: 0.015 [0.018] vs 0.03 [0.03]; p = 0.02). Differences in microbiota characteristics from baseline were no longer significant at the end of the chemotherapy cycle. Conclusions Conventional chemotherapy results in significant changes in gut microbiota characteristics during the period of predicted myelosuppression post-chemotherapy. Further study is indicated to link microbiome changes during chemotherapy to clinical outcomes.

scholarly journals The microbial community of the gut differs between piglets fed sow milk, milk replacer or bovine colostrum

2017 ◽  
Vol 117 (7) ◽  
pp. 964-978 ◽  
Author(s):  
Ann-Sofie R. Poulsen ◽  
Nadieh de Jonge ◽  
Sugiharto Sugiharto ◽  
Jeppe L. Nielsen ◽  
Charlotte Lauridsen ◽  
...  
Keyword(s):  
Gut Microbiota ◽  
Amplicon Sequencing ◽  
Bovine Colostrum ◽  
Milk Replacer ◽  
Rrna Gene ◽  
Bacterial Dna ◽  
Faecal Samples ◽  
Milk Replacers ◽  
The 16S Rrna Gene ◽  
Gut Microbiota Composition

AbstractThe aim of this study was to characterise the gut microbiota composition of piglets fed bovine colostrum (BC), milk replacer (MR) or sow milk (SM) in the post-weaning period. Piglets (n36), 23-d old, were randomly allocated to the three diets. Faecal samples were collected at 23, 25, 27 and 30 d of age. Digesta from the stomach, ileum, caecum and mid-colon was collected at 30 d of age. Bacterial DNA from all samples was subjected to amplicon sequencing of the 16S rRNA gene. Bacterial enumerations by culture and SCFA analysis were conducted as well. BC-piglets had the highest abundance ofLactococcusin the stomach (P<0·0001) and ileal (P<0·0001) digesta, whereas SM-piglets had the highest abundance ofLactobacillusin the stomach digesta (P<0·0001). MR-piglets had a high abundance of Enterobacteriaceae in the ileal digesta (P<0·0001) and a higher number of haemolytic bacteria in ileal (P=0·0002) and mid-colon (P=0·001) digesta than SM-piglets. BC-piglets showed the highest colonic concentration of iso-butyric and iso-valeric acid (P=0·02). Sequencing and culture showed that MR-piglets were colonised by a higher number of Enterobacteriaceae, whereas the gut microbiota of BC-piglets was characterised by a change in lactic acid bacteria genera when compared with SM-piglets. We conclude that especially the ileal microbiota of BC-piglets had a closer resemblance to that of SM-piglets in regard to the abundance of potential enteric pathogens than did MR-piglets. The results indicate that BC may be a useful substitute for regular milk replacers, and as a feeding supplement in the immediate post-weaning period.

scholarly journals Changes In The Gut Microbiota After Hepatitis C Virus Eradication

2021 ◽  
Author(s):  
Takashi Honda ◽  
Masatoshi Ishigami ◽  
Kenta Yamamoto ◽  
Tomoaki Takeyama ◽  
Takanori Ito ◽  
...  
Keyword(s):  
Hepatitis C Virus ◽  
Hepatitis C ◽  
Gut Microbiota ◽  
Illumina Miseq ◽  
Rrna Gene ◽  
Virus Eradication ◽  
Sequencing Platform ◽  
Direct Acting Antiviral ◽  
Faecal Samples ◽  
Before And After

Abstract The gut microbiota interacts with infectious diseases and affects host immunity. It has also been reported that liver disease is associated with changes in the gut microbiota. To investigate changes in the gut microbiota before and after eradication of hepatitis C virus (HCV) by direct-acting antiviral (DAA) treatment in patients with chronic hepatitis C (CHC), we investigated 42 samples from 14 CHC patients who received DAA therapy for HCV. Faecal samples were obtained before treatment (Pre), when treatment ended (EOT), and 24 weeks after treatment ended (Post24). The target V3–4 region of the 16S rRNA gene from faecal samples was amplified using the Illumina Miseq sequencing platform. The diversity of the gut microbiota did not differ significantly between Pre, EOT, and Post24. PCoA analysis showed that for each patient, the values at Pre, EOT, and Post 24 were concentrated within a small area. LEfSe analysis showed that the relative abundances of Faecalibacterium and Bacillus were increased at EOT and further increased at Post24, and these genera were significantly increased at Post24 compared to Pre. These results suggest that changes in the gut microbiota need to be considered as among the various effects on living organisms observed after HCV elimination.

Evaluation of Effects of Laboratory Disinfectants on Mouse Gut Microbiota

2021 ◽  
Author(s):  
Joseph D Sciurba ◽  
George E Chlipala ◽  
Stefan J Green ◽  
Martha A Delaney ◽  
Jeffrey D Fortman ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Gut Microbiota ◽  
Microbial Communities ◽  
Amplicon Sequencing ◽  
Fecal Microbiota ◽  
Β Diversity ◽  
Invaluable Tool ◽  
Potential Factor ◽  
Mouse Gut Microbiota ◽  
Potassium Peroxymonosulfate

Disturbances in the gut microbiota are known to be associated with numerous human diseases. Mice have proven to be an invaluable tool for investigating the role of the gut microbiota in disease processes. Nonexperimental factors related to maintaining mice in the laboratory environment are increasingly being shown to have inadvertent effects on the gut microbiotaand may function as confounding variables. Microisolation technique is a term used to describe the common biosecuritypractice of spraying gloved hands with disinfectant before handling research mice. This practice prevents contamination with pathogenic microorganisms. To investigate if exposure to disinfectants can affect the mouse gut microbiota, C57BL/6 micewere exposed daily for 27 consecutive days to commonly used laboratory disinfectants through microisolation technique.The effects of 70% ethanol and disinfectant products containing chlorine dioxide, hydrogen peroxide, or potassium peroxymonosulfate were each evaluated. Fecal pellets were collected after 7, 14, 21, and 28 d of disinfectant exposure, and cecal contents were collected at day 28. DNA extractions were performed on all cecal and fecal samples, and microbial community structure was characterized using 16S ribosomal RNA amplicon sequencing. Alpha and β diversity metrics and taxon-level analyses were used to evaluate differences in microbial communities. Disinfectant had a small but significant effect on fecal microbial communities compared with sham-exposed controls, and effects varied by disinfectant type. In general, longerexposure times resulted in greater changes in the fecal microbiota. Effects on the cecal microbiota were less pronounced and only seen with the hydrogen peroxide and potassium peroxymonosulfate disinfectants. These results indicate that laboratory disinfectant use should be considered as a potential factor that can affect the mouse gut microbiota.

scholarly journals Gut Microbiome and Metabolome Profiles Associated with High-Fat Diet in Mice

Metabolites ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 482
Author(s):  
Jae-Kwon Jo ◽  
Seung-Ho Seo ◽  
Seong-Eun Park ◽  
Hyun-Woo Kim ◽  
Eun-Ju Kim ◽  
...  
Keyword(s):  
Gut Microbiota ◽  
Relative Abundance ◽  
High Fat Diet ◽  
Amplicon Sequencing ◽  
Gas Chromatography Mass Spectrometry ◽  
Control Group ◽  
Rrna Gene ◽  
High Fat ◽  
Underlying Mechanisms ◽  
Insight Into

Obesity can be caused by microbes producing metabolites; it is thus important to determine the correlation between gut microbes and metabolites. This study aimed to identify gut microbiota-metabolomic signatures that change with a high-fat diet and understand the underlying mechanisms. To investigate the profiles of the gut microbiota and metabolites that changed after a 60% fat diet for 8 weeks, 16S rRNA gene amplicon sequencing and gas chromatography-mass spectrometry (GC-MS)-based metabolomic analyses were performed. Mice belonging to the HFD group showed a significant decrease in the relative abundance of Bacteroidetes but an increase in the relative abundance of Firmicutes compared to the control group. The relative abundance of Firmicutes, such as Lactococcus, Blautia, Lachnoclostridium, Oscillibacter, Ruminiclostridium, Harryflintia, Lactobacillus, Oscillospira, and Erysipelatoclostridium, was significantly higher in the HFD group than in the control group. The increased relative abundance of Firmicutes in the HFD group was positively correlated with fecal ribose, hypoxanthine, fructose, glycolic acid, ornithine, serum inositol, tyrosine, and glycine. Metabolic pathways affected by a high fat diet on serum were involved in aminoacyl-tRNA biosynthesis, glycine, serine and threonine metabolism, cysteine and methionine metabolism, glyoxylate and dicarboxylate metabolism, and phenylalanine, tyrosine, and trypto-phan biosynthesis. This study provides insight into the dysbiosis of gut microbiota and metabolites altered by HFD and may help to understand the mechanisms underlying obesity mediated by gut microbiota.

scholarly journals Reversion of Gut Microbiota during the Recovery Phase in Patients with Asymptomatic or Mild COVID-19: Longitudinal Study

2021 ◽  
Vol 9 (6) ◽  
pp. 1237
Author(s):  
Han-Na Kim ◽  
Eun-Jeong Joo ◽  
Chil-Woo Lee ◽  
Kwang-Sung Ahn ◽  
Hyung-Lae Kim ◽  
...  
Keyword(s):  
Gut Microbiota ◽  
Gastrointestinal Symptoms ◽  
Amplicon Sequencing ◽  
Recovery Phase ◽  
Fecal Samples ◽  
Intestinal Microbes ◽  
Gut Dysbiosis ◽  
16S Rrna Amplicon Sequencing ◽  
Microbiome Data ◽  
Negative Conversion

Patients with COVID-19 have been reported to experience gastrointestinal symptoms as well as respiratory symptoms, but the effects of COVID-19 on the gut microbiota are poorly understood. We explored gut microbiome profiles associated with the respiratory infection of SARS-CoV-2 during the recovery phase in patients with asymptomatic or mild COVID-19. A longitudinal analysis was performed using the same patients to determine whether the gut microbiota changed after recovery from COVID-19. We applied 16S rRNA amplicon sequencing to analyze two paired fecal samples from 12 patients with asymptomatic or mild COVID-19. Fecal samples were selected at two time points: during SARS-CoV-2 infection (infected state) and after negative conversion of the viral RNA (recovered state). We also compared the microbiome data with those from 36 healthy controls. Microbial evenness of the recovered state was significantly increased compared with the infected state. SARS-CoV-2 infection induced the depletion of Bacteroidetes, while an abundance was observed with a tendency to rapidly reverse in the recovered state. The Firmicutes/Bacteroidetes ratio in the infected state was markedly higher than that in the recovered state. Gut dysbiosis was observed after infection even in patients with asymptomatic or mild COVID-19, while the composition of the gut microbiota was recovered after negative conversion of SARS-CoV-2 RNA. Modifying intestinal microbes in response to COVID-19 might be a useful therapeutic alternative.

scholarly journals Comparative analysis of the gut microbiota of mice fed a diet supplemented with raw and cooked beef loin powder

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Hye-Jin Kim ◽  
Dongwook Kim ◽  
Kwan-Woo Kim ◽  
Sang-Hoon Lee ◽  
Aera Jang
Keyword(s):  
Fatty Acid ◽  
Comparative Analysis ◽  
Gut Microbiota ◽  
Ribosomal Rna ◽  
Relative Abundance ◽  
Short Chain Fatty Acid ◽  
Dietary Supplementation ◽  
Acid Synthesis ◽  
Chain Fatty Acid ◽  
Increasing Trend

AbstractWe used 16S ribosomal RNA sequencing to evaluate changes in the gut microbiota of mice fed a diet supplemented with either raw or cooked beef loin powder for 9 weeks. Male BALB/c mice (n = 60) were randomly allocated to five groups: mice fed AIN-93G chow (CON), chow containing 5% (5RB) and 10% (10RB) raw beef loin powder, and chow containing 5% (5CB) and 10% (10CB) cooked beef loin powder. Dietary supplementation with both RB and CB increased the relative abundance of Clostridiales compared to the CON diet (p < 0.05). Mice fed 10RB showed a significantly higher relative abundance of Firmicutes (p = 0.018) and Lactobacillus (p = 0.001) than CON mice, and the ratio of Firmicutes/Bacteroidetes showed an increasing trend in the 10RB mice (p > 0.05). Mice fed 10CB showed a higher abundance of Peptostreptococcaceae and a lower abundance of Desulfovibrionaceae compared with the CON mice (p < 0.05). Genes for glycan biosynthesis, which result in short-chain fatty acid synthesis, were enriched in the CB mice compared to the RB mice, which was correlated to a high abundance of Bacteroides. Overall, dietary RB and CB changed the gut microbiota of mice (p < 0.05).

scholarly journals Citrus polymethoxyflavones attenuate metabolic syndrome by regulating gut microbiome and amino acid metabolism

2020 ◽  
Vol 6 (1) ◽  
pp. eaax6208 ◽  
Author(s):  
Su-Ling Zeng ◽  
Shang-Zhen Li ◽  
Ping-Ting Xiao ◽  
Yuan-Yuan Cai ◽  
Chu Chu ◽  
...  
Keyword(s):  
Metabolic Syndrome ◽  
Amino Acid ◽  
Gut Microbiota ◽  
Metabolic Diseases ◽  
Amplicon Sequencing ◽  
Therapeutic Interventions ◽  
Protective Effects ◽  
Fecal Microbiome ◽  
Metabolomic Profiling ◽  
Branched Chain

Metabolic syndrome (MetS) is intricately linked to dysregulation of gut microbiota and host metabolomes. Here, we first find that a purified citrus polymethoxyflavone-rich extract (PMFE) potently ameliorates high-fat diet (HFD)–induced MetS, alleviates gut dysbiosis, and regulates branched-chain amino acid (BCAA) metabolism using 16S rDNA amplicon sequencing and metabolomic profiling. The metabolic protective effects of PMFE are gut microbiota dependent, as demonstrated by antibiotic treatment and fecal microbiome transplantation (FMT). The modulation of gut microbiota altered BCAA levels in the host serum and feces, which were significantly associated with metabolic features and actively responsive to therapeutic interventions with PMFE. Notably, PMFE greatly enriched the commensal bacterium Bacteroides ovatus, and gavage with B. ovatus reduced BCAA concentrations and alleviated MetS in HFD mice. PMFE may be used as a prebiotic agent to attenuate MetS, and target-specific microbial species may have unique therapeutic promise for metabolic diseases.

scholarly journals Comparison of PCR versus PCR-Free DNA Library Preparation for Characterising the Human Faecal Virome

Viruses ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 2093
Author(s):  
Shen-Yuan Hsieh ◽  
Mohammad A. Tariq ◽  
Andrea Telatin ◽  
Rebecca Ansorge ◽  
Evelien M. Adriaenssens ◽  
...  
Keyword(s):  
Alpha Diversity ◽  
Diversity Indices ◽  
P Value ◽  
Library Preparation ◽  
High Genetic Diversity ◽  
Sequencing Platform ◽  
Viral Genomes ◽  
Healthy Donors ◽  
Faecal Samples ◽  
Sequencing Platforms

The human intestinal microbiota is abundant in viruses, comprising mainly bacteriophages, occasionally outnumbering bacteria 10:1 and is termed the virome. Due to their high genetic diversity and the lack of suitable tools and reference databases, the virome remains poorly characterised and is often referred to as “viral dark matter”. However, the choice of sequencing platforms, read lengths and library preparation make study design challenging with respect to the virome. Here we have compared the use of PCR and PCR-free methods for sequence-library construction on the Illumina sequencing platform for characterising the human faecal virome. Viral DNA was extracted from faecal samples of three healthy donors and sequenced. Our analysis shows that most variation was reflecting the individually specific faecal virome. However, we observed differences between PCR and PCR-free library preparation that affected the recovery of low-abundance viral genomes. Using three faecal samples in this study, the PCR library preparation samples led to a loss of lower-abundance vOTUs evident in their PCR-free pairs (vOTUs 128, 6202 and 8364) and decreased the alpha-diversity indices (Chao1 p-value = 0.045 and Simpson p-value = 0.044). Thus, differences between PCR and PCR-free methods are important to consider when investigating “rare” members of the gut virome, with these biases likely negligible when investigating moderately and highly abundant viruses.

scholarly journals Encapsulated cyclosporine does not change the composition of the human microbiota when assessed ex vivo and in vivo

2020 ◽  
Vol 69 (6) ◽  
pp. 854-863
Author(s):  
Catherine O'Reilly ◽  
Órla O’Sullivan ◽  
Paul D. Cotter ◽  
Paula M. O’Connor ◽  
Fergus Shanahan ◽  
...  
Keyword(s):  
Pilot Study ◽  
Gut Microbiota ◽  
Targeted Delivery ◽  
Healthy Subjects ◽  
Ex Vivo ◽  
16S Rrna Gene Sequencing ◽  
Rrna Gene ◽  
Microbiota Composition ◽  
Faecal Samples

Introduction. Management of steroid-refractory ulcerative colitis has predominantly involved treatment with systemic cyclosporine A (CyA) and infliximab. Aim. The purpose of this study was to assess the effect of using a colon-targeted delivery system CyA formulation on the composition and functionality of the gut microbiota. Methodology. Ex vivo faecal fermentations from six healthy control subjects were treated with coated minispheres (SmPill) with (+) or without (−) CyA and compared with a non-treated control in a model colon system. In addition, the in vivo effect of the SmPill+CyA formulation was investigated by analysing the gut microbiota in faecal samples collected before the administration of SmPill+CyA and after 7 consecutive days of administration from eight healthy subjects who participated in a pilot study. Results. Analysis of faecal samples by 16S rRNA gene sequencing indicated little variation in the diversity or relative abundance of the microbiota composition before or after treatment with SmPill minispheres with or without CyA ex vivo or with CyA in vivo. Short-chain fatty acid profiles were evaluated using gas chromatography, showing an increase in the concentration of n-butyrate (P=0.02) and acetate (P=0.32) in the faecal fermented samples incubated in the presence of SmPill minispheres with or without CyA. This indicated that increased acetate and butyrate production was attributed to a component of the coated minispheres rather than an effect of CyA on the microbiota. Butyrate and acetate levels also increased significantly (P=0.05 for both) in the faecal samples of healthy individuals following 7 days’ treatment with SmPill+CyA in the pilot study. Conclusion. SmPill minispheres with or without CyA at the clinically relevant doses tested here have negligible direct effects on the gut microbiota composition. Butyrate and acetate production increased, however, in the presence of the beads in an ex vivo model system as well as in vivo in healthy subjects. Importantly, this study also demonstrates the relevance and value of using ex vivo colon models to predict the in vivo impact of colon-targeted drugs directly on the gut microbiota.

Sign in / Sign up

Export Citation Format

Share Document