Search results for "Intestinal microbiome"
showing 10 items of 186 documents
A widely used sampling device in colorectal cancer screening programmes allows for large-scale microbiome studies.
2018
We read with interest the article by Passamonti et al ,1 reporting the performance of two different faecal immunochemical tests (FITs) highlighting the importance of standardisation and validation of screening methodologies. Conventionally, laboratory-based FIT is the preferred approach in testing for occult blood in faeces, which includes colorectal cancer screening programmes.2–4 The potential of preserving stable faecal samples in a widely used FIT buffer for microbiome research would enable prospective microbiome studies in generally healthy subjects undergoing colorectal cancer screening. For this purpose, we evaluated faecal sample stability in the commonly used OC-Sensor (Eiken Chemi…
Systematic gene overexpression in Candida albicans identifies a regulator of early adaptation to the mammalian gut.
2018
International audience; Candida albicans is part of the human gastrointestinal (GI) microbiota. To better understand how C. albicans efficiently establishes GI colonisation, we competitively challenged growth of 572 signature-tagged strains (~10% genome coverage), each conditionally overexpressing a single gene, in the murine gut. We identified CRZ2, a transcription factor whose overexpression and deletion respectively increased and decreased early GI colonisation. Using clues from genome-wide expression and gene-set enrichment analyses, we found that the optimal activity of Crz2p occurs under hypoxia at 37°C, as evidenced by both phenotypic and transcriptomic analyses following CRZ2 geneti…
N-3 polyunsaturated fatty acids: An innovative strategy against obesity and related metabolic disorders, intestinal alteration and gut microbiota dys…
2019
Obesity is now widely recognized to be associated with low-grade systemic inflammation. It has been shown that high-fat feeding modulates gut microbiota which strongly increased intestinal permeability leading to lipopolysaccharide absorption causing metabolic endotoxemia that triggers inflammation and metabolic disorders. N-3 polyunsaturated fatty acids (PUFAs) have been shown associated with anti-obesity properties, but results still remain heterogeneous and very few studies underlined the metabolic pathways involved. Thus, the use of Fat-1 transgenic mice allows to better understanding whether endogenous n-3 PUFAs enrichment contributes to obesity and associated metabolic disorders preve…
Functional comparison of bacteria from the human gut and closely related non-gut bacteria reveals the importance of conjugation and a paucity of moti…
2016
International audience; The human GI tract is a complex and still poorly understood environment, inhabited by one of the densest microbial communities on earth. The gut microbiota is shaped by millennia of evolution to co-exist with the host in commensal or symbiotic relationships. Members of the gut microbiota perform specific molecular functions important in the human gut environment. This can be illustrated by the presence of a highly expanded repertoire of proteins involved in carbohydrate metabolism, in phase with the large diversity of polysaccharides originating from the diet or from the host itself that can be encountered in this environment. In order to identify other bacterial fun…
Melatonin in Early Nutrition: Long-Term Effects on Cardiovascular System
2021
Breastfeeding protects against adverse cardiovascular outcomes in the long term. Melatonin is an active molecule that is present in the breast milk produced at night beginning in the first stages of lactation. This indoleamine appears to be a relevant contributor to the benefits of breast milk because it can affect infant health in several ways. The melatonin concentration in breast milk varies in a circadian pattern, making breast milk a chrononutrient. The consumption of melatonin can induce the first circadian stimulation in the infant’s body at an age when his/her own circadian machinery is not functioning yet. This molecule is also a powerful antioxidant with the ability to act on infa…
A Weaning Reaction to Microbiota Is Required for Resistance to Immunopathologies in the Adult.
2019
International audience; Microbes colonize all body surfaces at birth and participate in the development of the immune system. In newborn mammals, the intestinal microbiota is first shaped by the dietary and immunological components of milk and then changes upon the introduction of solid food during weaning. Here, we explored the reactivity of the mouse intestinal immune system during the first weeks after birth and into adulthood. At weaning, the intestinal microbiota induced a vigorous immune response—a “weaning reaction”—that was programmed in time. Inhibition of the weaning reaction led to pathological imprinting and increased susceptibility to colitis, allergic inflammation, and cancer …
The Interplay between Nutrition, Innate Immunity, and the Commensal Microbiota in Adaptive Intestinal Morphogenesis
2021
The gastrointestinal tract is a functionally and anatomically segmented organ that is colonized by microbial communities from birth. While the genetics of mouse gut development is increasingly understood, how nutritional factors and the commensal gut microbiota act in concert to shape tissue organization and morphology of this rapidly renewing organ remains enigmatic. Here, we provide an overview of embryonic mouse gut development, with a focus on the intestinal vasculature and the enteric nervous system. We review how nutrition and the gut microbiota affect the adaptation of cellular and morphologic properties of the intestine, and how these processes are interconnected with innate immunit…
Ketogenic diet and microbiota: Friends or enemies?
2019
Over the last years, a growing body of evidence suggests that gut microbial communities play a fundamental role in many aspects of human health and diseases. The gut microbiota is a very dynamic entity influenced by environment and nutritional behaviors. Considering the influence of such a microbial community on human health and its multiple mechanisms of action as the production of bioactive compounds, pathogens protection, energy homeostasis, nutrients metabolism and regulation of immunity, establishing the influences of different nutritional approach is of pivotal importance. The very low carbohydrate ketogenic diet is a very popular dietary approach used for different aims: from weight …
The Monoclonal Antitoxin Antibodies (Actoxumab–Bezlotoxumab) Treatment Facilitates Normalization of the Gut Microbiota of Mice with Clostridium diffi…
2016
Antibiotics have significant and long-lasting impacts on the intestinal microbiota and consequently reduce colonization resistance against Clostridium difficile infection (CDI). Standard therapy using antibiotics is associated with a high rate of disease recurrence, highlighting the need for novel treatment strategies that target toxins, the major virulence factors, rather than the organism itself. Human monoclonal antibodies MK-3415A (actoxumab–bezlotoxumab) to C. difficile toxin A and toxin B, as an emerging non-antibiotic approach, significantly reduced the recurrence of CDI in animal models and human clinical trials. Although the main mechanism of protection is through direct neutraliza…
Protective effect of quercetin on high-fat diet-induced non-alcoholic fatty liver disease in mice is mediated by modulating intestinal microbiota imb…
2016
Gut microbiota is involved in obesity, metabolic syndrome and the progression of nonalcoholic fatty liver disease (NAFLD). It has been recently suggested that the flavonoid quercetin may have the ability to modulate the intestinal microbiota composition, suggesting a prebiotic capacity which highlights a great therapeutic potential in NAFLD. The present study aims to investigate benefits of experimental treatment with quercetin on gut microbial balance and related gut-liver axis activation in a nutritional animal model of NAFLD associated to obesity. C57BL/6J mice were challenged with high fat diet (HFD) supplemented or not with quercetin for 16 weeks. HFD induced obesity, metabolic syndrom…