Search results for " microbiome"
showing 10 items of 253 documents
Protease‐activated receptor signaling in intestinal permeability regulation
2019
Protease-activated receptors (PARs) are a unique class of G-protein-coupled transmembrane receptors, which revolutionized the perception of proteases from degradative enzymes to context-specific signaling factors. Although PARs are traditionally known to affect several vascular responses, recent investigations have started to pinpoint the functional role of PAR signaling in the gastrointestinal (GI) tract. This organ is exposed to the highest number of proteases, either from the gut lumen or from the mucosa. Luminal proteases include the host's digestive enzymes and the proteases released by the commensal microbiota, while mucosal proteases entail extravascular clotting factors and the enzy…
Lack of significant differences between gastrointestinal tract microbial population structure of Helicobacter pylori-infected subjects before and 2 y…
2020
Background According to recent estimates 80% of Latvian population is infected with Helicobacter pylori thus their susceptibility to numerous gastric tract diseases is increased. The 1st line H. pylori eradication therapy includes treatment with clarithromycin in combination with amoxicillin or metronidazole and a proton pump inhibitor. However, potential adverse events caused by such therapies to microbiome are insufficiently studied. Objective This study aimed to evaluate the long-term effect of H. pylori eradication on human gastrointestinal tract (GIT) microbiome. Methods The assessment of H pylori eradication impact on GIT microbiome was done by analyzing 120 samples acquired from 60 s…
Microbiome response to foam fractionation and ozonation in RAS
2022
Efficient water treatment is required to maintain high water quality and control microbial growth in recirculating aquaculture systems (RAS). Here, we examined the effects of two treatment methods, ozonation and foam fractionation, separately and combined, on the microbiology in twelve identical experimental RAS with rainbow trout (Oncorhyncus mykiss) during 8 weeks. Microbes suspended in water and growing in biofilter biofilms were examined using flow cytometry analysis and high throughput sequencing of the 16S rRNA gene. The results showed that foam fractionation did not cause large changes in abundance or overall community composition of free-living microbes. Instead, through decreasing …
Health and disease imprinted in the time variability of the human microbiome
2015
Human microbiota plays an important role in determining changes from health to disease. Increasing research activity is dedicated to understand its diversity and variability. We analyse 16S rRNA and whole genome sequencing (WGS) data from the gut microbiota of 97 individuals monitored in time. Temporal fluctuations in the microbiome reveal significant differences due to factors that affect the microbiota such as dietary changes, antibiotic intake, early gut development or disease. Here we show that a fluctuation scaling law describes the temporal variability of the system and that a noise-induced phase transition is central in the route to disease. The universal law distinguishes healthy fr…
Baseline Gut Microbiota Composition Is Associated With Schistosoma mansoni Infection Burden in Rodent Models
2020
In spite of growing evidence supporting the occurrence of complex interactions between Schistosoma and gut bacteria in mice and humans, no data is yet available on whether worm-mediated changes in microbiota composition are dependent on the baseline gut microbial profile of the vertebrate host. In addition, the impact of such changes on the susceptibility to, and pathophysiology of, schistosomiasis remains largely unexplored. In this study, mice colonized with gut microbial populations from a human donor (HMA mice), as well as microbiota-wild type (WT) animals, were infected with Schistosoma mansoni, and alterations of their gut microbial profiles at 50 days post-infection were compared to …
Effects of HIV, antiretroviral therapy and prebiotics on the active fraction of the gut microbiota
2018
In a recent blinded randomized study, we found that in HIV-infected individuals a short supplementation with prebiotics (scGOS/lcFOS/glutamine) ameliorates dysbiosis of total gut bacteria, particularly among viremic untreated patients. Our study goal was to determine the fraction of the microbiota that becomes active during the intervention and that could provide additional functional information.A total of six healthy individuals, and 16 HIV-infected patients comprising viremic untreated patients (n = 5) and antiretroviral therapy-treated patients that are further divided into immunological responders (n = 7) and immunological nonresponders (n = 4) completed the 6-week course of prebiotic …
Angiosperm to Gymnosperm host-plant switch entails shifts in microbiota of the Welwitschia bug, Probergrothius angolensis (Distant, 1902).
2019
The adaptation of herbivorous insects to new host plants is key to their evolutionary success in diverse environments. Many insects are associated with mutualistic gut bacteria that contribute to the host's nutrition and can thereby facilitate dietary switching in polyphagous insects. However, how gut microbial communities differ between populations of the same species that feed on different host plants remains poorly understood. Most species of Pyrrhocoridae (Hemiptera: Heteroptera) are specialist seed-feeders on plants in the family Malvaceae, although populations of one species, Probergrothius angolensis, have switched to the very distantly related Welwitschia mirabilis plant in the Nami…
Gut Microbiota and Risk of Developing Celiac Disease
2016
Gut microbiota shapes the development of the mucosal immune system and may provide protection against immune-mediated diseases. Celiac disease (CD) is a chronic inflammatory condition triggered by dietary gluten proteins, recently associated with gut microbiota alterations in cross-sectional studies comparing patients and controls. Whether or not these differences are causally related to the disease has yet to be elucidated, but evaluation of specific bacteria isolated from CD patients in experimental models suggests that they can promote an adverse response to dietary gluten, whereas other commensal bacteria can be protective. Genetic and environmental factors associated with increased CD …
The gut microbiota - a modulator of endothelial cell function and a contributing environmental factor to arterial thrombosis.
2019
Introduction: There is emerging evidence linking the commensal gut microbiota with the development of cardiovascular disease and arterial thrombosis. In immunothrombosis, the host clotting system protects against the dissemination of invading microbes, not considering the huge number of microbes that interact with host physiology in a mutualistic fashion. Areas covered: Interestingly, recent research revealed that colonizing gut microbes profoundly influence host innate immune pathways that support arterial thrombus growth. The gut microbiota promotes arterial thrombus formation by enhancing the pro-adhesive capacity of the vascular endothelium, triggering hepatic von Willebrand factor synt…
The Association between Cardiorespiratory Fitness and Gut Microbiota Composition in Premenopausal Women
2017
Abstract The aim of this study was to investigate the association between cardiorespiratory fitness and gut microbiota composition in premenopausal women. The participants consisted of 71 premenopausal Finnish women (aged 19–49 years). Gut microbiota were analyzed using flow cytometry, 16S rRNA gene hybridization and DNA-staining. Maximum oxygen uptake (VO₂ₘₐₓ) was assessed by respiratory gas analyzer and body composition by Bioimpdance. We found that participants with low VO₂ₘₐₓ had lower Bacteroides, but higher Eubacterium rectale-Clostridium coccoides than the high VO₂ₘₐₓ group (p < 0.05 for all). VO₂ₘₐₓ was inversely associated with EreC (r = −0.309, p = 0.01) but not with other bact…