Thermoneutral housing worsens MASLD and reveals defective brown adipose tissue response to β3-adrenergic stimulation.

Metabolic dysfunction-associated steatotic liver disease (MASLD), and its more advanced stage metabolic dysfunction-associated steatohepatitis, is the most common chronic liver disease, constituting a major public health issue. Relevant preclinical models are needed to define molecular mechanisms underlying MASLD pathogenesis and evaluate therapeutic approaches. The majority of the lipids accumulating in the liver upon MASLD originate from adipose tissue and appropriate models to study the liver-adipose tissue dialog are also needed.

Effects of a highly simplified microbiota on postnatal intestinal, immune, and brain development.

At birth, the newborn mammal enters a highly microbial world, leading to colonization of the gut by trillions of microorganisms, known as the microbiota. We previously reported that germ-free (GF) mice have altered brain development in the first days of life, suggesting that the arrival of microbes at birth is essential for normal brain development. However, GF mice are a highly artificial model system, with known deficits in immune and intestinal development.

Perinatal morphine exposure induces long-term changes in the intestinal microbiota of male and female rats.

The increased use of opioids by women of reproductive age has resulted in a dramatic rise in the number of infants exposed to opioids in utero. Although perinatal opioid exposure (POE) has been associated with an elevated risk of infection and hospitalization later in life, the mechanisms by which opioids influence immune development and maturation are not fully elucidated. Alterations in the intestinal microbiota composition, which lead to changes in immune training and maturation, could be at play.

Maternal emulsifier consumption alters the offspring early-life microbiota and goblet cell function leading to long-lasting diseases susceptibility.

Early-life acquisition of microbiota and, consequently, immune system development, both lastingly impacts health. Accordingly, we hypothesized that disturbing the microbiota of lactating mothers via consumption of dietary emulsifiers might alter the microbiota, and perhaps the immune system, of their offspring, thereby increasing susceptibility to microbiota-mediated diseases, including colitis and metabolic syndrome. Here we report that, in mice, maternal consumption of carboxymethylcellulose and polysorbate-80 resulted in transient alterations in offspring microbiotas that were necessary and sufficient to increase proneness to colitis and metabolic syndrome in young adulthood.

Substitution of polysorbates by plant-based emulsifiers: impact on vitamin D bioavailability and gut health in mice.

Although long considered safe, recent data have shown that emulsifiers such as polysorbates promoted intestinal inflammation and were associated with increased risks of developing chronic pathologies. We evaluated the potential of plant-based emulsifiers (pea protein isolate, PPI, and corn arabinoxylans, CAX) as alternatives to Polysorbate 80 (Tween 80, T80). Combining PPI and CAX led to a similar vitamin D bioavailability to T80 in vitro and in vivo in mice.

Adherent-invasive in Crohn's disease: the 25th anniversary.

In 1998, Arlette Darfeuille-Michaud, Christel Neut and Jean-Frederic Colombel discovered a novel pathovar of , adherent and invasive (AIEC), in the ileum of patients with Crohn's disease (CD), that was genetically distinct from diarrheagenic , could adhere to and invade intestinal epithelial cells and survive in macrophages. The consistent association between AIEC and CD (approximately 30% across the world), their ability to exploit CD-associated genetic traits, and virulence in preclinical colitis models but not healthy hosts spurred global research to elucidate their pathogenicity. Research focused on integrating AIEC with the microbiome, metabolome, metagenome, host response and the impact of diet and antimicrobials has linked the luminal microenvironment and AIEC metabolism to health and disease.

Microbiota encroachment and a gut-adipose-liver axis in metabolic dysfunction-associated steatotic liver disease.

Metabolic dysfunction-associated steatotic liver disease (MASLD) affects ∼40% of adults, but causal mechanisms remain elusive. Preclinical models implicate the gut microbiota in MASLD pathogenesis, yet translation to humans is hampered by variability in microbial composition. We addressed this gap by investigating whether stable, quantitative gut phenotypes, including microbiota encroachment, are pathological features of MASLD.

Diet-pathobiont interplay in health and inflammatory bowel disease.

The intestinal microbiota plays a crucial role in maintaining host health by participating in various beneficial functions. However, under certain conditions, it can contribute to the development of inflammatory bowel disease (IBD) and other chronic inflammatory conditions. Importantly, not all commensal microbiota members are drivers of inflammation.

Consumption of dietary emulsifiers increases sensitivity to social stress in mice: A potential role for the COX molecular pathway.

Background: Chronic low-grade inflammation and exposure to stress are key contributing factors in the etiology and progression of many neuropsychiatric disorders. Dietary emulsifiers, such as carboxymethylcellulose (CMC) and polysorbate-80 (P80), are commonly added to processed foods and drinks and are classified by the Food and Drug Administration (FDA) as generally recognized as safe (GRAS). Recently, however, we and others have reported that these additives at translationally relevant doses cause low-grade intestinal inflammation, microbiota dysbiosis, and alterations in gene expression in brain areas that mediate behavioral and neuroendocrine responses to stress-provoking stimuli.

The microbiota shapes the development of the mouse hypothalamic paraventricular nucleus.

Microbes massively colonize the mammalian newborn at birth. We previously reported that the microbiota influences key neurodevelopmental events, e.g.

Food additive mixtures and type 2 diabetes incidence: Results from the NutriNet-Santé prospective cohort.

Background: Mixtures of food additives are daily consumed worldwide by billions of people. So far, safety assessments have been performed substance by substance due to lack of data on the effect of multiexposure to combinations of additives. Our objective was to identify most common food additive mixtures, and investigate their associations with type 2 diabetes incidence in a large prospective cohort.

Inhibition of Atg7 in intestinal epithelial cells drives resistance against Citrobacter rodentium.

Autophagy, a cytoprotective mechanism in intestinal epithelial cells, plays a crucial role in maintaining intestinal homeostasis. Beyond its cell-autonomous effects, the significance of autophagy in these cells is increasingly acknowledged in the dynamic interplay between the microbiota and the immune response. In the context of colon cancer, intestinal epithelium disruption of autophagy has been identified as a critical factor influencing tumor development.

microbiota model recapitulates and predicts individualised sensitivity to dietary emulsifier.

Background: Non-absorbed dietary emulsifiers, including carboxymethylcellulose (CMC), directly disturb intestinal microbiota, thereby promoting chronic intestinal inflammation in mice. A randomised controlled-feeding study (Functional Research on Emulsifiers in Humans, FRESH) found that CMC also detrimentally impacts intestinal microbiota in some, but not all, healthy individuals.

Objectives: This study aimed to establish an approach for predicting an individual's sensitivity to dietary emulsifiers via their baseline microbiota.

Mucus-penetrating microbiota drive chronic low-grade intestinal inflammation and metabolic dysregulation.

Metabolic syndrome is, in humans, associated with alterations in the composition and localization of the intestinal microbiota, including encroachment of bacteria within the colon's inner mucus layer. Possible promoters of these events include dietary emulsifiers, such as carboxymethylcellulose (CMC) and polysorbate-80 (P80), which, in mice, result in altered microbiota composition, encroachment, low-grade inflammation and metabolic syndrome. While assessments of gut microbiota composition have largely focused on fecal/luminal samples, we hypothesize an outsized role for changes in mucus microbiota in driving low-grade inflammation and its consequences.

binary toxin CDT induces biofilm-like persisting microcolonies.

Clinical symptoms of infection (CDI) range from diarrhea to pseudomembranous colitis. A major challenge in managing CDI is the high rate of relapse. Several studies correlate the production of CDT binary toxin by clinical strains of with higher relapse rates.

Comparative analysis of the duodenojejunal microbiome with the oral and fecal microbiomes reveals its stronger association with obesity and nutrition.

The intestinal microbiota is increasingly recognized as a crucial player in the development and maintenance of various chronic conditions, including obesity and associated metabolic diseases. While most research focuses on the fecal microbiota due to its easier accessibility, the small intestine, as a major site for nutrient sensing and absorption, warrants further investigation to determine its microbiota composition and functions. Here, we conducted a clinical research project in 30 age- and sex-matched participants with ( = 15) and without ( = 15) obesity.

International consensus statement on microbiome testing in clinical practice.

There is growing interest in the potential exploitation of the gut microbiome as a diagnostic tool in medicine, but evidence supporting its clinical usefulness is scarce. An increasing number of commercial providers offer direct-to-consumer microbiome diagnostic tests without any consensus on their regulation or any proven value in clinical practice, which could result in considerable waste of individual and health-care resources and potential drawbacks in the clinical management of patients. We convened an international multidisciplinary expert panel to standardise best practices of microbiome testing for clinical implementation, including recommendations on general principles and minimum requirements for their provision, indications, pre-testing protocols, method of analyses, reporting of results, and potential clinical value.

Minibioreactor arrays to model microbiome response to alcohol and tryptophan in the context of alcohol-associated liver disease.

The intestinal microbiota (IM) plays a role in the severity of alcohol-associated liver disease. Modifying severe alcohol-associated hepatitis (AH) dysbiosis improves liver injury through tryptophan (Trp) metabolites and the aryl hydrocarbon receptor (AhR). However, Trp's effect on the IM in alcohol use disorder (AUD) patients remains unclear.

Western diet promotes endometriotic lesion growth in mice and induces depletion of Akkermansia muciniphila in intestinal microbiota.

Background: Endometriosis, affecting 10% of women in their reproductive years, remains poorly understood. Both individual and environmental unexplained factors are implicated in this heterogenous condition. This study aims to examine the influence of a Western diet on endometriosis lesion development in mice and to uncover the mechanisms involved.

Hyaluronan nanoplatelets exhibit extended residence time compared to spherical and ellipsoidal nanomaterials with equivalent surface potentials and volumes after oral delivery in rats.

The physicochemical properties of colloidal particles-such as size, surface properties, and morphology-play a crucial role in determining their behaviors and transit through the gastrointestinal (GI) tract. While some data exist for nonspherical nanomaterials (NMs) composed of silica or polystyrene, there is limited understanding of NMs composed of polysaccharides and polymers. This study explores the fate and GI tract residence time of hyaluronan-based NMs with distinctive hexagonal morphology and flat surfaces (nanoplatelets) following administration to rats.

Fecal let-7b and miR-21 directly modulate the intestinal microbiota, driving chronic inflammation.

Inflammatory bowel diseases (IBD) etiology is multifactorial. Luminal microRNAs (miRNAs) have been suspected to play a role in the promotion of chronic inflammation, but the extent to which fecal miRNAs are interacting with the intestinal ecosystem in a way that contribute to diseases, including IBD, remains unknown. Here, fecal let-7b and miR-21 were found elevated, associated with inflammation, and correlating with multiple bacteria in IBD patients and IL-10 mice, model of spontaneous colitis.

Prevention and cure of murine infection by a Lachnospiraceae strain.

We sought to better understand how intestinal microbiota confer protection against () infection (CDI). We utilized gnotobiotic altered Schaedler flora (ASF) mice, which lack the abnormalities of germfree (GF) mice as well as the complexity and heterogeneity of antibiotic-treated mice. Like GF mice, ASF mice were highly prone to rapid lethal CDI, without antibiotics, while very low infectious doses resulted in chronic CDI.

Impact of high-dose cholecalciferol (vitamin D3) and inulin prebiotic on intestinal and airway microbiota in adults with cystic fibrosis: A 2 × 2 randomized, placebo-controlled, double-blind pilot study.

Background: Cystic fibrosis (CF) is a multi-organ disease caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR). Individuals with CF often have gastrointestinal (GI) dysbiosis due to chronic inflammation and antibiotic use. Previous studies suggested a role for vitamin D in reversing the GI dysbiosis found in CF.

Microbiota during pregnancy and early life: role in maternal-neonatal outcomes based on human evidence.

Here, we explored the vast potential of microbiome-based interventions in preventing and managing non-communicable diseases including obesity, diabetes, allergies, celiac disease, inflammatory bowel diseases, malnutrition, and cardiovascular diseases across different life stages. We discuss the intricate relationship between microbiome and non-communicable diseases, emphasizing on the "window of opportunity" for microbe-host interactions during the first years after birth. Specific biotics and also live biotherapeutics including fecal microbiota transplantation emerge as pivotal tools for precision medicine, acknowledging the "one size doesn't' fit all" aspect.