Search Results (49)

Iron is essential for numerous physiological processes, including oxygen transport, energy metabolism, and immune function. This study evaluated the efficacy and safety of three iron formulations combining heme and non-heme iron, comparing them with existing market products and the original form of iron. The formulations tested were GlobiFer^® Forte, a combination of heme and non-heme iron containing 18 mg of elemental iron (hereinafter referred to as nutraceutical product 1); GlobiFer^®, a combination of heme and non-heme iron containing 14 mg of elemental iron (hereinafter referred to as nutraceutical product 2); and a double dose of nutraceutical product 2. Using an in vitro 3D intestinal barrier model, all three formulations significantly increased tight junction protein expression and TEER values, indicating preserved barrier integrity. Iron absorption analysis revealed that all three iron formulations had higher absorption rates than controls. Nutraceutical product 1 showed the highest absorption, associated with increased expression of the iron transporters such as the primary non-heme iron transporter, DMT1, and the leading apical heme transporter, HCP-1. All three new formulations increased ferritin and ferroportin levels, markers of systemic iron storage and regulation. Nutraceutical product 1 was found to be the most effective, based on percentage. Overall, combining heme and non-heme iron improved intestinal absorption and supported iron metabolism, with Nutraceutical Product 1 proving the most promising in terms of efficacy and safety. These results support the development of optimised dual-source iron supplements to improve bioavailability and maintain intestinal barrier integrity, prerequisites for better efficacy and tolerability in clinical use. Full article

Enterotoxigenic Escherichia coli (ETEC) is a major cause of diarrhea in pigs. Virulence factors, such as colonization factors and enterotoxins, bind to specific receptors on intestinal epithelial cells (IECs), impairing the integrity of the IEC barrier by inducing cell death. Pyroptosis is a newly discovered form of programmed cell death (PCD), which is widely involved in the pathogenesis of multiple infectious gastrointestinal diseases. However, it is still unclear whether pyroptosis contributes to the ETEC-mediated damage of IECs. This study demonstrated that ETEC infection activated NLRP3 inflammasome and triggered gasdermin D (GSDMD)-executed pyroptosis of mouse IECs in vitro and in vivo. Mechanistically, ETEC infection triggered endoplasmic reticulum (ER) stress response to increase the expression of thioredoxin-interacting protein (TXNIP) by upregulation of C/EBP homologous protein (CHOP), which subsequently activated NLRP3 inflammasome. Removal of ER stress by tauroursodeoxycholic acid (TUDCA) alleviated the pyroptosis of IECs that was caused by ETEC infection. In addition, the induced ER stress impaired mitochondria and led to mitochondrial reactive oxygen species (mtROS) overproduction and cytosolic release of mitochondrial DNA (mtDNA), which activated STING, another factor that contributed to ETEC-triggered pyroptosis. Chemical inhibition of STING attenuated ETEC-induced pyroptosis of IECs. Collectively, this study demonstrated that the activation of the STING/ER stress/mitochondrial impairment/NLRP3 inflammasome axis is a critical pathway in the ETEC infection-derived pyroptosis of IECs. Hence, targeting ER stress response may serve as a promising therapeutic strategy to prevent ETEC infection caused damage to IECs. Full article

The intestine is a complex organ whose main functions are food digestion and nutrient absorption. It is therefore of great interest for pharmaceutical research as a preferred route for drug delivery. In vitro intestinal models are valuable tools for the preclinical evaluation of absorption, distribution, metabolism, and excretion of new therapeutic formulations; consequently, several attempts have been made to recreate the human intestine barrier in vitro. The models so far set up were aimed at mimicking specific intestinal features related to the molecules or processes under investigation. Artificial membranes are suitable to study passive absorption; systems based on 2D/3D cell cultures reproduce the transcellular pathway; organs-on-a-chip mimic the in vivo cellular and mechanical complexity, allowing the identification of the multiple factors involved in molecular interactions with the intestinal barrier; and intestine explants replicate in full the native organ under controlled conditions, thus providing the most comprehensive in vitro model. All these models have advantages and disadvantages but all have given important contribution to advance the knowledge on the interaction of drugs, toxins, and xenobiotic with the intestinal barrier. Full article

Background/Objectives: Ulcerative colitis (UC) pathogenesis involves gut barrier dysfunction, dysregulated immune responses, and gut microbiota imbalance. Alfalfa polysaccharide (APS), a bioactive compound with immunomodulatory potential, remains underexplored in intestinal inflammation. While APS exhibits anti-inflammatory properties in vitro, its in vivo efficacy, mechanisms, and ability to restore gut microbiota and barrier integrity in UC are unclear. This study aims to investigate the treatment effect of APS on dextran sulfate sodium (DSS)-induced colitis in mice and confirm its prebiotic potential. Methods: A mouse model of ulcerative colitis was induced by DSS. RNA sequencing, Western blotting, the terminal deoxynucleotidyl transferase dUTP nick end labeling technique, and an immuno-histochemical technique were used to study the mechanism of action by which APS at different dosages relieves DSS-induced colitis. Results: The findings show that APS alleviated the symptoms of colitis in mice given DSS, improved the gut morphology, heightened goblet cells production, increased the levels of IL-10 and IL-22, decreased the levels of TNF-α, IL-1β, and IL-6, and prevented the activation of the TLR4/MyD88/NF-κB pathways. Additionally, they maintained the integrity of the intestine by enhancing the expression of the mucins MUC2 and MUC5AC and by increasing the amounts of ZO-1, Occludin, and Claudin-1 proteins. Moreover, APS supported the growth of probiotic bacteria, including unclassified_f_lachnospiraceae, Parabacteroides, Alistipes, and Mucispirillum, and in particular, Parabacteroides distasonis, which is strongly associated with decreased pro-inflammatory cytokine through the inhibition of the TLR4-MyD88-NFκB pathways. Conclusions: APS can be used as a new type of prebiotic to improve UC by regulating intestinal flora and enhancing intestinal barrier function against the TLR4-MyD88-NFκB pathway. Full article

This study elucidates how the quorum-sensing (QS) signal 3OC12-HSL exacerbates enterotoxigenic E. coli (ETEC) pathogenicity and intestinal barrier dysfunction. In vitro, 3OC12-HSL enhanced ETEC C83902 growth (66.7% CFU increase at 8 h) and dysregulated stress/growth genes (e.g., eight-fold rmf upregulation under static conditions). In synthetic gut microbiota, 3OC12-HSL selectively augmented E. coli colonization (37.6% 16S rDNA increase at 12 h). Murine studies revealed 3OC12-HSL reduced jejunal villus height (381.5 μm vs. 543.2 μm in controls), elevated serum LPS, D-lactate, and DAO, and altered microbial composition (Firmicutes/Bacteroidetes imbalance). The lactonase AiiA reversed these effects by degrading 3OC12-HSL. It abrogated bacterial growth stimulation (in vitro CFU restored to baseline), normalized microbiota diversity (Shannon index recovered to control levels), suppressed pro-inflammatory cytokines (IL-6/TNF-α reduction), and restored intestinal integrity (villus length: 472.5 μm, 20.5% increase vs. ETEC-infected mice). Our findings establish AiiA as a potent quorum-quenching agent that counteracts ETEC virulence via targeted signal inactivation, highlighting its translational value. Full article

Oxidative stress, driven by impaired antioxidant defence systems, is a major contributor to cognitive decline and neurodegenerative processes in brain ageing. This study investigates the neuroprotective effects of a natural compound mixture—composed of Hericium erinaceus, Palmitoylethanolamide, Bilberry extract, and Centella asiatica—using a multi-step in vitro strategy. An initial evaluation in a 3D intestinal epithelial model demonstrated that the formulation preserves barrier integrity and may be bioaccessible, as evidenced by transepithelial electrical resistance (TEER) and the expression of tight junctions. Subsequent analysis in an integrated gut–brain axis model under oxidative stress conditions revealed that the formulation significantly reduces inflammatory markers (NF-κB, TNF-α, IL-1β, and IL-6; about 1.5-fold vs. H₂O₂), reactive oxygen species (about 2-fold vs. H₂O₂), and nitric oxide levels (about 1.2-fold vs. H₂O₂). Additionally, it enhances mitochondrial activity while also improving antioxidant responses. In a co-culture of neuronal and astrocytic cells, the combination upregulates neurotrophic factors such as BDNF and NGF (about 2.3-fold and 1.9-fold vs. H₂O₂). Crucially, the formulation also modulates key biomarkers associated with cognitive decline, reducing APP and phosphorylated tau levels (about 98% and 1.6-fold vs. H₂O₂) while increasing Sirtuin 1 and Nrf2 expression (about 3.6-fold and 3-fold vs. H₂O₂). These findings suggest that this nutraceutical combination may support the cellular pathways involved in neuronal resilience and healthy brain ageing, offering potential as a functional food ingredient or dietary supplement. Full article

Accurate in vitro models of intestinal permeability are essential for predicting oral drug absorption. Standard models like Caco-2 cells have well-known limitations, including lack of segment-specific physiology, but are widely used. Emerging models such as organoid-derived monolayers and microphysiological systems (MPS) offer enhanced physiological relevance but require comparative validation. We performed a head-to-head evaluation of Caco-2 cells, human jejunal (J2) and duodenal (D109) enteroid-derived cells, and EpiIntestinal^TM tissues cultured on either static Transwell and flow-based MPS platforms. We assessed tissue morphology, barrier function (TEER, dextran leakage), and permeability of three model small molecules (caffeine, propranolol, and indomethacin), integrating the data into a physiologically based gut absorption model (PECAT) to predict human oral bioavailability. J2 and D109 cells demonstrated more physiologically relevant morphology and higher TEER than Caco-2 cells, while the EpiIntestinal^TM model exhibited thicker and more uneven tissue structures with lower TEER and higher passive permeability. MPS cultures offered modest improvements in epithelial architecture but introduced greater variability, especially with enteroid-derived cells. Predictions of human fraction absorbed (F_abs) were most accurate when using static Caco-2 data with segment-specific corrections based on enteroid-derived values, highlighting the utility of combining traditional and advanced in vitro gut models to optimize predictive performance for F_abs. While MPS and enteroid-based systems provide physiological advantages, standard static models remain robust and predictive when used with in silico modeling. Our findings support the need for further refinement of enteroid-MPS integration and advocate for standardized benchmarking across gut model systems to improve translational relevance in drug development and regulatory reviews. Full article

Polyphenols are compounds derived from plant-based food possessing numerous biological activities, including inhibiting oxidative stress, suppressing inflammation, and regulating gut microbiota. In this study, we investigated the effects of quinic acid, a phenolic acid from millet, on the regulation of gut microbiota and intestinal inflammation and further discussed the possible mechanism. The results showed that quinic acid could improve the microbiota composition of the feces of patients with inflammatory bowel disease (IBD) by in vitro anaerobic fermentation by increasing the abundance of beneficial genera including Bifidobacterium, Weissella, etc., and decreasing that of harmful genera like Escherichia-Shigella. Quinic acid treatment could alleviate the symptoms of dextran sodium sulfate (DSS)-induced colitis in mice, maintain the intestinal barrier, down-regulate the expression of inflammatory factors such as IL-1β and TNF-α, and inhibit the activation of the MyD88/NF-κB signaling pathway. In addition, quinic acid also improved the diversity of gut microbiota in mice with colitis. Furthermore, pseudo-germ-free colitis mice proved that the effect of quinic acid on intestinal inflammation was diminished after removing most gut microbiota by antibiotic treatment, suggesting that gut microbiota play important roles during the regulation of colitis by quinic acid. In a word, our study verified the regulatory effects of quinic acid on intestinal inflammation, depending on gut microbiota regulation and NF-κB signaling suppression. Full article

Background: Venous hypertension is the primary cause of the disorder known as chronic venous insufficiency (CVI), which affects the lower extremities’ venous system. Because of its biological proper ties, which include anti-inflammatory, antioxidant, and vascular tone enhancement, medicinal herbs and natural substances are highly recommended for treating CVI. Therefore, this study examined the advantages of a novel combination composed of hypersmin, pumpkin seed and amaranthus extracts (named MIX) in modulating different parameters involved with CVI. Methods: The capacity of these natural compounds to pass across the intestinal barrier and reach the bloodstream was examined using a 3D intestinal barrier model that mimics oral ingestion. The biological effects of the MIX were then compared to those of a commercial product using an in vitro CVI model. Results: The findings demonstrate that the new MIX significantly reduced inflammation while increasing nitric oxide production. The MIX was more successful than the commercial product in reducing apoptosis while restoring vasal tone and extracellular matrix activity. Conclusions: This work has therefore demonstrated the positive benefits of extracts from amaranthus, pumpkin seed and hypersmin in the context of CVI, raising the prospect of creating a unique combination for patients with CVI. Full article

Irritable Bowel Syndrome (IBS) is a disorder of gut- brain interaction characterized by recurrent abdominal pain associated with altered bowel habits. The therapeutic options for IBS patients include the use of probiotics. The aim of this study was to assess the effect of a multi-strain probiotic made up by Lactobacillus rhamnosus LR 32, Bifidobacterium lactis BL 04, and Bifidobacterium longum BB 536 (Serobioma, Bromatech s.r.l., Milano, Italy) on an in vitro model of the intestinal epithelial barrier in the presence of mucosal mediators that are released by IBS patients. IBS (n = 28; IBS with predominant diarrhea, IBS-D = 10; IBS with predominant constipation, IBS-C = 9; and IBS with mixed bowel habits, IBS-M = 9) patients, diagnosed according to the Rome IV criteria, and asymptomatic controls (ACs, n = 7) were enrolled. Mucosal mediators that were spontaneously released by colonic biopsies were collected (supernatants). Two doses of Serobioma were tested with/without IBS/AC mediators. RNA was extracted from Caco-2 cells to evaluate the tight junction (TJ) expression. Serobioma (10⁶ CFU/mL) significantly reinforced the Caco-2 monolayer compared to growth medium alone (p < 0.05). IBS supernatants significantly increased Caco-2 paracellular permeability compared to the AC supernatants. The co-incubation of Caco-2 cells with IBS supernatants and Serobioma (10⁶ CFU/mL) avoided the paracellular permeability alterations that were induced by IBS supernatants alone (p < 0.001), and, in particular, IBS-D and IBS-M ones. The co-incubation of Serobioma (10⁶ CFU/mL) and IBS-D supernatants significantly increased ZO-1 expression compared to Caco-2 cells incubated with supernatants alone (p < 0.05), as confirmed via qPCR analyses. Serobioma (10⁶ CFU/mL) counteracts the paracellular permeability changes that are induced by IBS supernatants, in particular IBS-D and IBS-M supernatants, likely modulating ZO-1 expression. Full article

Current in vitro methods for intestinal barrier assessment predominantly utilize two-dimensional (2D) membrane inserts in standard culture plates, which are widely recognized for their inability to replicate the microenvironment critical to intestinal barrier functionality. Our study focuses on creating an alternative method for intestinal barrier function by integrating a 3D-printed transwell device with a paper-based membrane. Caco-2 cells were grown on a Matrigel-modified paper membrane, in which the tight junction formation was evaluated using TEER measurements. Neutrophil-like dHL-60 cells were employed for neutrophil extracellular trap (NET) formation experiments. Furthermore, intestinal barrier dysfunction was demonstrated using NET-isolated and Staurosporine interventions. Intestinal barrier characteristics were investigated through immunofluorescence staining of specific proteins and scanning electron microscopy (SEM). Our paper-based intestinal barrier exhibited an increased resistance in a time-dependent manner, consistent with immunofluorescence images of Zonulin Occludens-1 (ZO-1) expression. Interestingly, immunofluorescence analysis revealed changes in the morphology of the intestinal barrier and the formation of surface villi. These disruptions were found to alter the localization of tight junctions, impacting epithelial polarization and surface functionality. Moreover, we successfully demonstrated the permeability of a paper-based intestinal barrier using FITC-dextran assay. Hence, the 3D-printed transwell device integrated with a paper membrane insert presents a straightforward, cost-effective, and sustainable platform for an in vitro cell model to evaluate intestinal barrier function. Full article

Background: In vitro findings on the biological functions of Lycium barbarum flavonoids (LBFs) as feed additives are limited. This study aimed to explore the effects of different concentrations of LBFs on the growth performance, immune function, intestinal barrier, and antioxidant capacity of meat ducks. A total of 240 one-day-old male meat ducks were randomly allocated to four groups, each receiving a basal diet supplemented with 0 (control), 250, 500, or 1000 mg/kg of LBFs for 42 d. Results: The results showed that dietary supplementation with 500 mg/kg of LBFs resulted in a significant increase in average daily feed intake, body weight, average daily gain, and feed conversion ratio. Dietary supplementation with 500 or 1000 mg/kg of LBFs resulted in significant decreases in serum levels of D-lactic acid and lipopolysaccharide. Dietary supplementation with 500 mg/kg LBFs significantly decreased diamine oxidase activity and enhanced the activities of catalase, total antioxidant capacity, and glutathione peroxidase in the jejunal mucosa, as well as the activity of total superoxide dismutase and the content of glutathione in the ileal mucosa, while significantly lowering the content of malondialdehyde in the ileal mucosa. Dietary supplementation with 500 mg/kg LBFs significantly up-regulated the mRNA expression of genes associated with intestinal barrier function and antioxidant capacity in the jejunal and ileal mucosa, as well as the protein expression of these antioxidant genes, and led to a significant reduction in the mRNA expression of pro-apoptotic and inflammatory-related genes. Conclusions: The addition of LBFs to the diet improved the growth performance, intestinal barrier function, immune response, and antioxidant capacity of the ducks, which may be closely associated with the activation of the Nrf2 signaling pathway and the inhibition of the NF-κB signaling pathway. The optimal dietary inclusion level of LBFs in ducks was 500 mg/kg. Full article

This investigation aimed to assess the in vitro and in silico biological properties of the ethyl acetate (EtOAc) extract obtained from leaves of Rubus ulmifolius Schott collected in Algeria. The phytochemical screening data disclosed that flavonoids, tannins, coumarins, saponins, and anthocyanins were abundant. High levels of total phenolics, total flavonoids and flavonols (523.25 ± 3.53 µg GAE/mg, 20.41 ± 1.80, and 9.62 ± 0.51 µg QE/mg respectively) were detected. Furthermore, GC-MS analysis was performed to identify low molecular weight compounds. d-(-)-Fructofuranose, gallic acid, caffeic acid, and catechin were detected as main metabolites of the EtOAc extract. The outcomes revealed that the extract exerted a potent antioxidant apt, and ensured significant bacterial growth inhibitory capacity, where the inhibition zone diameters ranged from 20.0 ± 0.5 to 24.5 ± 0.3 mm. These outcomes were confirmed through molecular docking against key bacterial enzymes that revealed significant interactions and binding affinities. d-(-)-Fructofuranose was identified as the most polar and flexible compound. Gallic acid and caffeic acid demonstrated higher unsaturation. Caffeic acid was well absorbed in the blood–brain barrier (BBB) and human intestine. Catechin was well absorbed in CaCO₃, and can act as an inhibitor of CYP1A2. These results highlight how crucial it is to keep looking into natural substances in the quest for more potent and targeted pathology therapies. Full article

Intestinal mucosal barrier damage is regarded as the critical factor through which chronic unpredictable mild stress (CUMS) leads to a variety of physical and mental health problems. However, the exact mechanism by which CUMS induces intestinal mucosal barrier damage is unclear. In this study, 14, 28, and 42 d CUMS model mice were established. The indicators related to ileal mucosal barrier damage (IMBD), the composition of the ileal microbiota and its amino acid (AA) and short-chain fatty acid (SCFA) metabolic functions, and free amino acid (FAA) and SCFA levels in the ileal lumen were measured before and after each stress period. The correlations between them are analyzed to investigate how CUMS induces intestinal mucosal barrier damage in male C57BL/6 mice. With the progression of CUMS, butyric acid (BA) levels decreased (14 and 28 d) and then increased (42 d), and IMBD progressively increased. In the late CUMS stage (42 d), the degree of IMBD is most severe and positively correlated with significantly increased BA levels (p < 0.05) in the ileal lumen and negatively correlated with significantly decreased FAAs, such as aspartic, glutamic, alanine, and glycine levels (p < 0.05). In the ileal lumen, the abundance of BA-producing bacteria (Muribaculaceae, Ruminococcus, and Butyricicoccus) and the gene abundance of specific AA degradation and BA production pathways and their related enzymes are significantly increased (p < 0.05). In addition, there is a significant decrease (p < 0.05) in the abundance of core bacteria (Prevotella, Lactobacillus, Turicibacter, Blautia, and Barnesiella) that rely on these specific AAs for growth and/or are sensitive to BA. These changes, in turn, promote further colonization of BA-producing bacteria, exacerbating the over-accumulation of BA in the ileal lumen. These results were validated by ileal microbiota in vitro culture experiments. In summary, in the late CUMS stages, IMBD is related to an excessive accumulation of BA caused by dysbiosis of the ileal microbiota and its overactive AA degradation. Full article

Background: To accurately measure permeability of compounds in the intestine, there is a need for preclinical in vitro models that accurately represent the specificity, integrity and complexity of the human small intestinal barrier. Intestine-on-chip systems hold considerable promise as testing platforms, but several characteristics still require optimization and further development. Methods: An established intestine-on-chip model for tissue explants was adopted for intestinal cell monolayer culture. A 3D-printed culture disc was designed to allow cell culture in static conditions and subsequent permeability studies in a dynamic environment. Membrane characteristics and standardized read-outs were investigated and compared to traditional permeability studies under static conditions. Results: By starting cultures outside the chip in conventional wells plates, the new cell disc design could support accurate cell monolayer formation for both Caco-2 and human enteroids. When transferred to the chip with laminar flow, there was accurate detection of barrier integrity (FD4 and Cascade Blue) and permeability (atenolol/antipyrine). Both flow and membrane characteristics had a significant impact on permeability outcomes. Conclusions: This novel intestinal cell-on-chip system offers large flexibility for intestinal permeability studies, although it still requires validation with more compounds to reveal its full potential. Full article