Search results for "Intestinal"
showing 10 items of 2024 documents
Mining metagenomic whole genome sequences revealed subdominant but constant Lactobacillus population in the human gut microbiota
2016
The genus Lactobacillus includes over 215 species that colonize plants, foods, sewage and the gastrointestinal tract (GIT) of humans and animals. In the GIT, Lactobacillus population can be made by true inhabitants or by bacteria occasionally ingested with fermented or spoiled foods, or with probiotics. This study longitudinally surveyed Lactobacillus species and strains in the feces of a healthy subject through whole genome sequencing (WGS) data-mining, in order to identify members of the permanent or transient populations. In three time-points (0, 670 and 700 d), 58 different species were identified, 16 of them being retrieved for the first time in human feces. L. rhamnosus, L. ruminis, L…
The Transcription Factor MAZR/PATZ1 Regulates the Development of FOXP3+ Regulatory T Cells
2019
Summary: Forkhead box protein P3+ (FOXP3+) regulatory T cells (Treg cells) play a key role in maintaining tolerance and immune homeostasis. Here, we report that a T cell-specific deletion of the transcription factor MAZR (also known as PATZ1) leads to an increased frequency of Treg cells, while enforced MAZR expression impairs Treg cell differentiation. Further, MAZR expression levels are progressively downregulated during thymic Treg cell development and during in-vitro-induced human Treg cell differentiation, suggesting that MAZR protein levels are critical for controlling Treg cell development. However, MAZR-deficient Treg cells show only minor transcriptional changes ex vivo, indicating…
Extraintestinal pathogenic Escherichia coli sequence type 131 H30-R and H30-Rx subclones in retail chicken meat, Italy
2016
Extraintestinal pathogenic Escherichia coli sequence type 131 (ST131), typically fluoroquinolone-resistant (FQ-R) and/or extended-spectrum β-lactamase (ESBL)-producing, has emerged globally. Among clinical isolates, ST131, primarily its H30-R and H30-Rx subclones, accounts for most antimicrobial-resistant E. coli and is the dominant E. coli strain worldwide. We assessed its prevalence and characteristics among raw chicken meat samples on sale in Palermo, Italy. A collection of 237 fluoroquinolone resistant and ESBL/AmpC producing E. coli isolates, which had been isolated from processed retail chicken meat in the period May 2013-April 2015, was analyzed. Established polymerase chain reaction…
Taste of Fat: A Sixth Taste Modality?
2015
International audience; An attraction for palatable foods rich in lipids is shared by rodents and humans. Over the last decade, the mechanisms responsible for this specific eating behavior have been actively studied, and compelling evidence implicates a taste component in the orosensory detection of dietary lipids [i.e., long-chain fatty acids (LCFA)], in addition to textural, olfactory, and postingestive cues. The interactions between LCFA and specific receptors in taste bud cells (TBC) elicit physiological changes that affect both food intake and digestive functions. After a short overview of the gustatory pathway, this review brings together the key findings consistent with the existence…
Human milk and mucosa-associated disaccharides impact on cultured infant fecal microbiota
2020
Human milk oligosaccharides (HMOs) are a mixture of structurally diverse carbohydrates that contribute to shape a healthy gut microbiota composition. The great diversity of the HMOs structures does not allow the attribution of specific prebiotic characteristics to single milk oligosaccharides. We analyze here the utilization of four disaccharides, lacto-N-biose (LNB), galacto-N-biose (GNB), fucosyl-α1,3-GlcNAc (3FN) and fucosyl-α1,6-GlcNAc (6FN), that form part of HMOs and glycoprotein structures, by the infant fecal microbiota. LNB significantly increased the total levels of bifidobacteria and the species Bifidobacterium breve and Bifidobacterium bifidum. The Lactobacillus genus levels wer…
Microevolutionary response of a gut nematode to intestinal inflammation.
2017
7 pages; International audience; Parasitic helminths interfere with the immune response of their hosts to establish long-lasting, chronic infections. While favorable to the parasite, the capacity to dampen the immune response can also provide a benefit to the host in terms of reduced risk of immune disorders and immunopathology. The immunomodulatory role of nematodes has been exploited in clinical trials to treat a number of inflammatory and immune diseases. However, how parasites adapt to an inflammatory environment remains a poorly explored question. Here, we conducted a serial passage experiment where the gut nematode Heligmosomoides polygyrus was maintained for nine generations in mice …
Redox signaling in the gastrointestinal tract.
2017
Redox signaling regulates physiological self-renewal, proliferation, migration and differentiation in gastrointestinal epithelium by modulating Wnt/β-catenin and Notch signaling pathways mainly through NADPH oxidases (NOXs). In the intestine, intracellular and extracellular thiol redox status modulates the proliferative potential of epithelial cells. Furthermore, commensal bacteria contribute to intestine epithelial homeostasis through NOX1- and dual oxidase 2-derived reactive oxygen species (ROS). The loss of redox homeostasis is involved in the pathogenesis and development of a wide diversity of gastrointestinal disorders, such as Barrett's esophagus, esophageal adenocarcinoma, peptic ulc…
Potential benefits of colostrum in gastrointestinal diseases
2016
This paper reviews the composition of colostrum and the potential preventive and therapeutic use of this "first milk" for treating various gastrointestinal disorders in humans. Colostrum is a complex biological liquid that is richer in antimicrobial peptides, immune-regulating compounds and growth factors than the subsequent mature milk. The main functions of colostrum are to provide essential nutritional components, strengthen the natural defense system, modulate immune response, balance intestinal microbiota and enhance the growth and repair of several tissues. Several studies and clinical trials carried out both in vitro and in vivo on humans and animals suggest the clinical benefits of …
Shifts in gut microbiota composition in an APP/PSS1 transgenic mouse model of Alzheimer's disease during lifespan.
2017
Alzheimer's disease (AD) is the most common form of dementia and one of the major causes of disability and dependency in older people. Accumulating evidences link gut microbiota with different diseases and its relationship with neurodegenerative diseases is becoming most intriguing. This study was aimed to compare the gut microbiota of transgenic APP/PS1 (TG) mice, a well‐established deterministic mouse model of AD, with their C57BL/6 wild‐type (WT) littermates. Faecal samples were collected from 3‐, 6‐ and 24‐month‐old mice and analysed by pyrosequencing of the V1–V3 region of the bacterial 16S rRNA genes. Bacterial profiles were similar in all young mice (3 months old), and started to div…
Microvesicles released from Giardia intestinalis disturb host-pathogen response in vitro
2017
Giardia intestinalis (G.I), is an anaerobic protozoan and the aetiological agent of giardiasis, a diarrhoea present worldwide and associated with poverty. G.I has a simple life cycle alternating between cyst and trophozoite. Cysts are transmitted orally to the stomach and transform to trophozoites in the intestine by a multifactorial process. Recently, microvesicles (MVs) have been found to be released from a wide range of eukaryotic cells. We have observed a release of MVs during the life cycle of G.I., identifying MVs from active trophozoites and from trophozoites differentiating to the cyst form. The aim of the current work was to investigate the role of MVs from G.I in the pathogenesis …