Exploring the impact of digestive physicochemical parameters of adults and infants on the pathophysiology of Cryptosporidium parvum using the dynamic TIM-1 gastrointestinal model.

Background: Human cryptosporidiosis is distributed worldwide, and it is recognised as a leading cause of acute diarrhoea and death in infants in low- and middle-income countries. Besides immune status, the higher incidence and severity of this gastrointestinal disease in young children could also be attributed to the digestive environment. For instance, human gastrointestinal physiology undergoes significant changes with age, however the role this variability plays in Cryptosporidium parvum pathogenesis is not known.

Large intestinal nutritional and physicochemical parameters from different dog sizes reshape canine microbiota structure and functions .

Different dog sizes are associated with variations in large intestinal physiology including gut microbiota, which plays a key role in animal health. This study aims to evaluate, using the CANIM-ARCOL (Canine Mucosal Artificial Colon), the relative importance of gut microbes physicochemical and nutritional parameters of the canine colonic environment in shaping microbiota structure and functions. CANIM-ARCOL was set up to reproduce nutrient availability, bile acid profiles, colonic pH, and transit time from small, medium, or large dogs according to data, while bioreactors were all inoculated with a fecal sample collected from medium size dogs ( = 2).

Development of a new antibiotic-induced dysbiosis model of the canine colonic microbiota.

As in humans, antibiotics are widely used in dogs to treat gastrointestinal infections, contributing to the global burden of antimicrobial resistance on both human and animal health. Close contact between pets and their owners can lead to horizontal transfer of gut microbes, including transmission of antibiotic resistance. Nevertheless, until now, the impact of antibiotics on the canine gut microbiota has been poorly described.

Canine Mucosal Artificial Colon: development of a new colonic in vitro model adapted to dog sizes.

Differences in dog breed sizes are an important determinant of variations in digestive physiology, mainly related to the large intestine. In vitro gut models are increasingly used as alternatives to animal experiments for technical, cost, societal, and regulatory reasons. Up to now, only one in vitro model of the canine colon incorporates the dynamics of different canine gut regions, yet no adaptations exist to reproduce size-related digestive parameters.

Transfer of the Integrative and Conjugative Element ICE of Streptococcus thermophilus in Physiological Conditions Mimicking the Human Digestive Ecosystem.

Metagenome analyses of the human microbiome suggest that horizontal gene transfer (HGT) is frequent in these rich and complex microbial communities. However, so far, only a few HGT studies have been conducted . In this work, three different systems mimicking the physiological conditions encountered in the human digestive tract were tested, including (i) the TNO gastro-Intestinal tract Model 1 (TIM-1) system (for the upper part of the intestine), (ii) the ARtificial COLon (ARCOL) system (to mimic the colon), and (iii) a mouse model.

Modelling of Oral Microbial Invasion in the Human Colon.

Recent advances in the human microbiome characterization have revealed significant oral microbial detection in stools of dysbiotic patients. However, little is known about the potential interactions of these invasive oral microorganisms with commensal intestinal microbiota and the host. In this proof-of-concept study, we proposed a new model of oral-to-gut invasion by the combined use of an model simulating both the physicochemical and microbial (lumen- and mucus-associated microbes) parameters of the human colon (M-ARCOL), a salivary enrichment protocol, and whole-metagenome shotgun sequencing.

Casein structures differently affect postprandial amino acid delivery through their intra-gastric clotting properties.

We aimed to assess if casein structure affects its digestion and its subsequent amino acid delivery kinetic. Higher nitrogen levels were recovered in dialysates after in vitro digestions of sodium caseinate (SC, formed of small aggregates) compared to micellar casein (MC, native form of casein) and calcium caseinate (CC, intermediate structure). Likewise, plasma indispensable amino-acid concentration peak was higher after SC compared to MC or CC ingestion in healthy volunteers in a randomized, double blind, cross-over study.

A child is not an adult: development of a new in vitro model of the toddler colon.

Early life is a critical period where gut ecosystem and functions are being established with significant impact on health. For regulatory, technical, and cost reasons, in vitro gut models can be used as a relevant alternative to in vivo assays. An exhaustive literature review was conducted to adapt the Mucosal Artificial Colon (M-ARCOL) to specific physicochemical (pH, transit time, and nutritional composition of ileal effluents) and microbial parameters from toddlers in the age range of 6 months-3 years, resulting in the Tm-ARCOL.

From Chihuahua to Saint-Bernard: how did digestion and microbiota evolve with dog sizes.

Health and well-being of dogs are of paramount importance to their owners. Digestion plays a key role in dog health, involving physicochemical, mechanical and microbial actors. However, decades of breeding selection led to various dog sizes associated with different digestive physiology and disease sensitivity.

In vitro models of the canine digestive tract as an alternative to in vivo assays: Advances and current challenges.

Dogs occupy a full place in the family, and their well-being is of paramount importance to their owners. Digestion, a complex process involving physicochemical, mechanical, and microbial parameters, plays a central role in maintaining canine health. As in vivo studies in dogs are increasingly restricted by ethical, regulatory, societal, and cost pressures, an alternative option is the use of in vitro models simulating the different compartments of the canine gastrointestinal tract.

Var CNCM I-1079 Reduces Expression of Genes Involved in Inflammatory Response in Porcine Cells Challenged by Enterotoxigenic and Influences Bacterial Communities in an In Vitro Model of the Weaning Piglet Colon.

Enterotoxigenic (ETEC) is the main infectious agent responsible for piglet post-weaning diarrhea with high mortality rates. Antimicrobials represent the current principal strategy for treating ETEC infections in pig farms, but the occurrence of multi-resistant bacterial strains has considerably increased in the last decades. Thus, finding non-antibiotic alternatives becomes a real emergency.

Nitric Oxide Impacts Human Gut Microbiota Diversity and Functionalities.

The disruption of gut microbiota homeostasis has been associated with numerous diseases and with a disproportionate inflammatory response, including overproduction of nitric oxide (NO) in the intestinal lumen. However, the influence of NO on the human gut microbiota has not been well characterized yet. We used fermentation systems inoculated with human fecal samples to monitor the effect of repetitive NO pulses on the gut microbiota.

Multi-targeted properties of the probiotic CNCM I-3856 against enterotoxigenic (ETEC) H10407 pathogenesis across human gut models.

Enterotoxigenic (ETEC) is one of the most common causes of acute traveler's diarrhea. Adhesins and enterotoxins constitute the major ETEC virulence traits. With the dramatic increase in antibiotic resistance, probiotics are considered a wholesome alternative to prevent or treat ETEC infections.

Pathogen Challenge and Dietary Shift Alter Microbiota Composition and Activity in a Mucin-Associated Model of the Piglet Colon (MPigut-IVM) Simulating Weaning Transition.

Enterotoxigenic (ETEC) is the principal pathogen responsible for post-weaning diarrhea in newly weaned piglets. Expansion of ETEC at weaning is thought to be the consequence of various stress factors such as transient anorexia, dietary change or increase in intestinal inflammation and permeability, but the exact mechanisms remain to be elucidated. As the use of animal experiments raise more and more ethical concerns, we used a recently developed model of piglet colonic microbiome and mucobiome, the MPigut-IVM, to evaluate the effects of a simulated weaning transition and pathogen challenge at weaning.

Weaning-associated feed deprivation stress causes microbiota disruptions in a novel mucin-containing in vitro model of the piglet colon (MPigut-IVM).

Background: Risk factors for the etiology of post-weaning diarrhea, a major problem in swine industry associated with enormous economic losses, remain to be fully elucidated. In concordance with the ethical concerns raised by animal experiments, we developed a new in vitro model of the weaning piglet colon (MPigut-IVM) including a mucin bead compartment to reproduce the mucus surface from the gut to which gut microbes can adhere.

Results: Our results indicated that the MPigut-IVM is able to establish a representative piglet archaeal and bacterial colon microbiota in terms of taxonomic composition and function.

Identification of Genes Specifically Expressed under Simulated Human Digestive Conditions Using R-IVET Technology.

Despite promising health effects, the probiotic status of a lactic acid bacterium widely used in dairy industry, requires further documentation of its physiological status during human gastrointestinal passage. This study aimed to apply recombinant-based in vivo technology (R-IVET) to identify genes triggered in a LMD-9 reference strain under simulated digestive conditions. First, the R-IVET chromosomal cassette and plasmid genomic library were designed to positively select activated genes.

Beneficial Effects of Natural Mineral Waters on Intestinal Inflammation and the Mucosa-Associated Microbiota.

Natural mineral water (NMWs) intake has been traditionally used in the treatment of various gastrointestinal diseases. We investigated the effect of two French NMWs, one a calcium and magnesium sulphate, sodium chloride, carbonic, and ferruginous water (NMW1), the other a mainly bicarbonate water (NMW2) on the prevention of intestinal inflammation. Intestinal epithelial cells stimulated with heat inactivated or HO were treated with NMWs to evaluate the anti-inflammatory effects.

Use of the Dynamic TIM-1 Model for an In-Depth Understanding of the Survival and Virulence Gene Expression of Shiga Toxin-Producing Escherichia coli in the Human Stomach and Small Intestine.

Due to obvious ethical and technical reasons, it remains very difficult to evaluate the survival and expression of virulence genes of food-borne pathogens, such as Shiga toxin-producing Escherichia coli (STEC) in the human gastrointestinal tract. Here, we describe the use of the dynamic TNO (Toegepast Natuurwetenschappelijk Onderzoek) gastrointestinal model (TIM-1) as a powerful in vitro tool to obtain the kinetics of STEC survival by plate counting, the regulation of major virulence genes by RT-qPCR, and the production of Shiga toxins by ELISA, in the human stomach and small intestine. The gut model was adapted in order that in vitro digestions were performed both under adult and child digestive conditions, specific at risk populations for STEC infections.

An Oral FMT Capsule as Efficient as an Enema for Microbiota Reconstruction Following Disruption by Antibiotics, as Assessed in an In Vitro Human Gut Model.

Fecal microbiota transplantation (FMT) is an innovative therapy already used in humans to treat infections associated with massive use of antibiotics. Clinical studies are obviously the gold standard to evaluate FMT efficiency but remain limited by regulatory, ethics, and cost constraints. In the present study, an in vitro model of the human colon reproducing medically relevant perturbation of the colonic ecosystem by antibiotherapy was used to compare the efficiency of traditional FMT enema formulations and a new oral capsule in restoring gut microbiota composition and activity.

Spatial and temporal modulation of enterotoxigenic E. coli H10407 pathogenesis and interplay with microbiota in human gut models.

Background: Enterotoxigenic Escherichia coli (ETEC) substantially contributes to the burden of diarrheal illnesses in developing countries. With the use of complementary in vitro models of the human digestive environment, TNO gastrointestinal model (TIM-1), and Mucosal Simulator of the Human Intestinal Microbial Ecosystem (M-SHIME), we provided the first detailed report on the spatial-temporal modulation of ETEC H10407 survival, virulence, and its interplay with gut microbiota. These systems integrate the main physicochemical parameters of the human upper digestion (TIM-1) and simulate the ileum vs ascending colon microbial communities and luminal vs mucosal microenvironments, captured from six fecal donors (M-SHIME).

Correction: Benefits of the ipowder® extraction process applied to Melissa officinalis L.: improvement of antioxidant activity and in vitro gastro-intestinal release profile of rosmarinic acid.

Correction for 'Benefits of the ipowder® extraction process applied to Melissa officinalis L.: improvement of antioxidant activity and in vitro gastro-intestinal release profile of rosmarinic acid' by Valérie Bardot et al., Food Funct.

Benefits of the ipowder® extraction process applied to Melissa officinalis L.: improvement of antioxidant activity and in vitro gastro-intestinal release profile of rosmarinic acid.

The objective of this study was to evaluate the benefits of a new extraction process, the ipowder® technology, applied to Melissa officinalis L. Compared to M. officinalis ground dry leaves, the ipowder® had a similar phytochemical fingerprint but contained twice the concentration of rosmarinic acid (by HPTLC and HPLC) and had a two-fold greater antioxidant activity (DPPH* method).

Food Chemicals Disrupt Human Gut Microbiota Activity And Impact Intestinal Homeostasis As Revealed By In Vitro Systems.

Growing evidence indicates that the human gut microbiota interacts with xenobiotics, including persistent organic pollutants and foodborne chemicals. The toxicological relevance of the gut microbiota-pollutant interplay is of great concern since chemicals may disrupt gut microbiota functions, with a potential impairment of host homeostasis. Herein we report within batch fermentation systems the impact of food contaminants (polycyclic aromatic hydrocarbons, polychlorobiphenyls, brominated flame retardants, dioxins, pesticides and heterocyclic amines) on the human gut microbiota by metatranscriptome and volatolome i.

Environmental Pollutant Benzo[]Pyrene Impacts the Volatile Metabolome and Transcriptome of the Human Gut Microbiota.

Benzo[]pyrene (B[]P) is a ubiquitous, persistent, and carcinogenic pollutant that belongs to the large family of polycyclic aromatic hydrocarbons. Population exposure primarily occurs via contaminated food products, which introduces the pollutant to the digestive tract. Although the metabolism of B[]P by host cells is well known, its impacts on the human gut microbiota, which plays a key role in health and disease, remain unexplored.