Search Results (4,025)

The Caco-2 in vitro model of the intestinal barrier is a well-established system for the investigation of the intestinal fate of orally ingested chemicals and drugs, and it has been used for over ten years by pharmaceutical industries as a model for absorption in preclinical studies. The Caco-2 model shows a fair correlation with in vivo drug absorption, though some inherent biases remain unresolved. Its main limitation lies in the lack of structural complexity, as it does not replicate the diverse cell types and mucus layer present in the human intestinal epithelium. Consequently, the development of advanced in vitro models of the intestinal barrier, that more structurally resemble the human intestinal epithelium physiology, has increased the potential applications of these models. Recently, Caco-2-based advanced intestinal models have proven effective in predicting nanomaterial uptake and transport across the intestinal barrier. The aim of this review is to provide a state-of-the-art of human in vitro intestinal barrier models for the study of translocation/uptake of nanoparticles relevant for oral exposure, including inorganic nanomaterials, micro/nano plastic, and fiber nanomaterials. The main effects of the above-mentioned nanomaterials on the intestinal barrier are also reported. Full article

Fungicides are compounds with potentially toxic effects on the human body, but the molecular mechanisms of their action have not yet been explained. The effect of cyprodinil on cell viability, apoptosis level, cell membrane function, cell morphology and expression of antioxidant enzyme genes in the A-375 and DLD-1 cell lines was examined. The cell lines were selected because they can be an excellent in vitro model of neoplastic changes occurring in the skin and large intestine after exposure to a fungicide. The fungicide selected for the study is commonly used in Poland to protect crops against fungi. Our results showed that the tested compound increased cell viability and proliferation, probably activated by mechanisms related to oxidative stress. Cyprodinil caused an increase in glutathione level (in A-375 by about 37% and in DLD-1 by about 28%) and oxidative stress enzymes activity, but not in apoptosis level. Its membrane interactions and its penetration into cells was concentration dependent. It is worth emphasizing that the novelty of our work lies in the use of non-traditional toxicological methods based on molecular analyses using human cell lines. This allowed us to demonstrate not only the toxicity of a single substance but also its behavior within cellular structures. Our findings suggest that cyprodinil may have tumor-promoting properties in skin and colorectal cancer cells. Full article

Human colorectal cancer (CRC) encompasses tumors affecting a segment of the large intestine (colon) and rectum. It is the third most commonly diagnosed malignancy and the second leading cause of cancer deaths worldwide. It is a multifactorial disease, whose carcinogenesis process involves genetic and epigenetic alterations in oncogenes and tumor suppressor genes, including genes related to DNA repair. The pathogenic mechanisms are described based on the pathways of chromosomal instability, microsatellite instability, and CpG island methylator phenotype. When detected early, CRC is potentially curable, and its treatment is based on the pathological characteristics of the tumor and factors related to the patient, as well as on drug efficacy and toxicity studies. Therefore, the aim of this study was to review the pathogenesis and molecular subtypes of CRC and to describe the main targets of disease-directed therapy used in patients refractory to current treatments. Full article

The gut microbiota of macaques, highly homologous to humans in biological characteristics and metabolic functions, serves as an ideal model for studying the mechanisms of human intestinal diseases and therapeutic approaches. A comprehensive characterization of the macaque gut microbiota provides unique insights into human health and disease. This study employs metagenomic sequencing to assess the gut microbiota of wild M. mulatta brevicaudus across various ages, sexes, and physiological states. The results revealed that the dominant bacterial species in various age groups included Segatella copri and Bifidobacterium adolescentis. The predominant bacterial species in various sexes included Alistipes senegalensis and Parabacteroides (specifically Parabacteroides merdae, Parabacteroides johnsonii, and Parabacteroides sp. CT06). The dominant species during lactation and non-lactation periods were identified as Alistipes indistinctus and Capnocytophaga haemolytica. Functional analysis revealed significant enrichment in pathways such as global and overview maps, carbohydrate metabolism and amino acid metabolism. This study enhances our understanding of how age, sex, and physiological states shape the gut microbiota in M. mulatta brevicaudus, offering a foundation for future research on (1) host–microbiome interactions in primate evolution, and (2) translational applications in human health, such as microbiome-based therapies for metabolic or immune-related disorders. Full article

Backgrounds and aim: Protective effects of natural compounds have been suggested in the prevention and treatment of radiation-induced mucositis or bacterial infections. In this study, the protective effects of proanthocyanidin-rich grape seed extract (GSE) on bacterial Lipopolysaccharide (LPS) and radiation-induced epithelial barrier damage and Reactive Oxygen Species (ROS) production were investigated in an in vitro model. Methods: Human intestinal epithelial cells Caco-2, previously treated with LPS, GSE, or LPS + GSE, were irradiated with 10 Gy divided into five daily treatments. Epithelial barrier integrity and ROS production were measured before and after each treatment. Results: Irradiation, at different doses, significantly increased intestinal permeability and ROS production; pretreatment with GSE was able to significantly prevent the increased intestinal permeability (4.63 ± 0.76 vs. 15.04 ± 1.5; p < 0.05) and ROS production (12.9 ± 1.08 vs. 1048 ± 0.5; p < 0.0001) induced by irradiation treatment. When the cells were pretreated with LPS, the same results were observed: GSE cotreatment was responsible for preventing permeability alterations (5.36 ± 0.16 vs. 49.26 ± 0.82; p < 0.05) and ROS production (349 ± 1 vs. 7897.67 ± 1.53; p < 0.0001) induced by LPS exposure when added to the irradiation treatment. Conclusions: The results of the present investigation demonstrated, in an in vitro model, that GSE prevents the damage to intestinal permeability and the production of ROS that are induced by LPS and ionizing radiation, suggesting a potential protective effect of this extract on the intestinal mucosa during irradiation treatment. Full article

The demand for wild animal meat, popularly called “bushmeat”, serves as a driving force behind the emergence of infectious diseases, potentially transmitting a variety of pathogenic bacteria to humans through handling and consumption. This study investigated the microbial load and bacterial diversity in bushmeat sourced from a prominent bushmeat market in Kumasi, Ghana. Carcasses of 61 wild animals, including rodents (44), antelopes (14), and African civets (3), were sampled for microbiological analysis. These samples encompassed meat, intestines, and anal and oral swabs. The total aerobic bacteria plate count (TPC), Enterobacteriaceae count (EBC), and fungal counts were determined. Bacterial identification was conducted using MALDI-TOF biotyping. Fungal counts were the highest across all animal groups, with African civets having 11.8 ± 0.3 log₁₀ CFU/g and 11.9 ± 0.2 log₁₀ CFU/g in intestinal and meat samples, respectively. The highest total plate count (TPC) was observed in rodents, both in their intestines (10.9 ± 1.0 log₁₀ CFU/g) and meat (10.9 ± 1.9 log₁₀ CFU/g). In contrast, antelopes exhibited the lowest counts across all categories, particularly in EBC from intestinal samples (6.1 ± 1.5 log₁₀ CFU/g) and meat samples (5.6 ± 1.2 log₁₀ CFU/g). A comprehensive analysis yielded 524 bacterial isolates belonging to 20 genera, with Escherichia coli (18.1%) and Klebsiella spp. (15.5%) representing the most prevalent species. Notably, the detection of substantial microbial contamination in bushmeat underscores the imperative for a holistic One Health approach to enhance product quality and mitigate risks associated with its handling and consumption. Full article

Background/Objectives: Gut microbiota research has gained momentum in recent years broadening knowledge of microbial components and their potential effects on health and well-being. Strong association between explicit microbes and metabolic diseases associated with obesity and type 2 diabetes mellitus, gastrointestinal disorders, neurodegenerative diseases, and even cancers have been established. Akkermansia muciniphila is a budding next-generation probiotic that plays an important role in systemic metabolism, intestinal health, and immune regulation, establishing strong implications for its use as a potent therapeutic intervention in diverse diseases. This project aimed at evaluating whether bacterial cell extracts of VH Akkermansia muciniphila (Vidya Strain; VS) can stimulate insulin secretion in INS-1 pancreatic beta cells and GLP-1 secretion in NCI-H716 human L-cells, both established in vitro models for studying metabolic regulation. Methods: Cultured VH Akkermansia muciniphila extracts were administered in a dose-dependent manner on INS-1 cells, and glucose-stimulated insulin secretion (GSIS) was measured via ELISA. Treated Human L-cell lines (NCI-H716) were analyzed for GLP-1 secretion. Results: Our study demonstrated that VH Akkermansia muciniphila extracts modestly increase insulin secretion from INS-1 beta cells and, more notably, induce a robust, dose-dependent rise in GLP-1 secretion from NCI-H716 L-cells, with the highest dose achieving over a 2000% increase comparable to glutamine. Conclusions: These findings suggest that VH A. muciniphila extracts may offer metabolic benefits by enhancing GLP-1 release, highlighting their potential for managing type 2 diabetes and obesity. Full article

T-2 toxin and HT-2 toxin are commonly found in agricultural products and animal feed, posing serious effects to both humans and animals. This study employed combination index (CI) modeling and metabolomics to assess the combined cytotoxic effects of T-2 and HT-2 on four porcine cell types: intestinal porcine epithelial cells (IPEC-J2), porcine Leydig cells (PLCs), porcine ear fibroblasts (PEFs), and porcine hepatocytes (PHs). Cell viability assays revealed a dose-dependent reduction in viability across all cell lines, with relative sensitivities in the order: IPEC-J2 > PLCs > PEFs > PHs. Synergistic cytotoxicity was observed at low concentrations, while antagonistic interactions emerged at higher doses. Untargeted metabolomic profiling identified consistent and significant metabolic perturbations in four different porcine cell lines under co-exposure conditions. Notably, combined treatment with T-2 and HT-2 resulted in a uniform downregulation of LysoPC (22:6), LysoPC (20:5), and LysoPC (20:4), implicating disruption of membrane phospholipid integrity. Additionally, glycerophospholipid metabolism was the most significantly affected pathway across all cell lines. Ether lipid metabolism was markedly altered in PLCs and PEFs, whereas PHs displayed a unique metabolic response characterized by dysregulation of tryptophan metabolism. This study identified markers of synergistic toxicity and common alterations in metabolic pathways across four homologous porcine cell types under the combined exposure to T-2 and HT-2 toxins. These findings enhance the current understanding of the molecular mechanisms underlying mycotoxin-induced the synergistic toxicity. Full article

Background: BDE-47, a pervasive environmental pollutant detected in >90% of human serum samples, is increasingly linked to metabolic disorders. This study investigates the specific impact of BDE-47 exposure on the gut microbiota in prediabetic mice and evaluates the efficacy of therapeutic interventions in mitigating these effects. Objectives: To determine whether BDE-47 exposure induces diabetogenic dysbiosis in prediabetic mice and to assess whether dietary interventions, such as grape exosomes and an antioxidant cocktail, can restore a healthy microbiota composition and mitigate diabetes risk. Methods: In this study, a prediabetic mouse model was established in 54 male SPF-grade C57BL/6J mice through a combination of high-sugar and high-fat diet feeding with streptozotocin injection. Oral glucose tolerance tests (OGTT) were conducted on day 7 and day 21 post-modeling to assess the establishment of the model. The criteria for successful model induction were defined as fasting blood glucose levels below 7.8 mmol/L and 2 h postprandial glucose levels between 7.8 and 11.1 mmol/L. Following confirmation of model success, a 3 × 3 factorial design was applied to allocate the experimental animals into groups based on two independent factors: BDE-47 exposure and exosome intervention. The BDE-47 exposure factor consisted of three dose levels—none, high-dose, and medium-dose—while the exosome intervention factor included three modalities—none, Antioxidant Nutrients Intervention, and Grape Exosomes Intervention. Fresh fecal samples were collected from mice two days prior to sacrifice. Cecal contents and segments of the small intestine were collected and transferred into 1.5 mL cryotubes. All sequences were clustered into operational taxonomic units (OTUs) based on defined similarity thresholds. To compare means across multiple groups, a two-way analysis of variance (ANOVA) was employed. The significance level was predefined at α = 0.05, and p-values < 0.05 were considered statistically significant. Bar charts and line graphs were generated using GraphPad Prism version 9.0 software, while statistical analyses were performed using SPSS version 20.0 software. Results: The results of 16S rDNA sequencing analysis of the microbiome showed that there was no difference in the α diversity of the intestinal microbiota in each group of mice (p > 0.05), but there was a difference in the Beta diversity (p < 0.05). At the gate level, the abundances of Proteobacteria, Campylobacterota, Desulfobacterota, and Fusobacteriota in the medium-dose BDE-7 group were higher than those in the model control group (p < 0.05). The abundance of Patellar bacteria was lower than that of the model control group (p < 0.05). The abundances of Proteobacteria and Campylobacterota in the high-dose BDE-7 group were higher than those in the model control group (p < 0.05). The abundance of Planctomycetota and Patescibacteria was lower than that of the model control group (p < 0.05), while the abundance of Campylobacterota in the grape exosome group was higher than that of the model control group (p < 0.05). The abundance of Patescibacteria was lower than that of the model control group (p < 0.05), while the abundance of Firmicutes and Fusobacteriota in the antioxidant nutrient group was higher than that of the model control group (p < 0.05). However, the abundance of Verrucomicrobiota and Patescibacteria was lower than that of the model control group (p < 0.05). At the genus level, the abundances of Bacteroides and unclassified Lachnospiraceae in the high-dose BDE-7 group were higher than those in the model control group (p < 0.05). The abundance of Lachnospiraceae NK4A136_group and Lactobacillus was lower than that of the model control group (p < 0.05). The abundance of Veillonella and Helicobacter in the medium-dose BDE-7 group was higher than that in the model control group (p < 0.05), while the abundance of Lactobacillus was lower (p < 0.05). The abundance of genera such as Lentilactobacillus and Faecalibacterium in the grape exosome group was higher than that in the model control group (p < 0.05). The abundance of Alloprevotella and Bacteroides was lower than that of the model control group (p < 0.05). In the antioxidant nutrient group, the abundance of Lachnospiraceae and Hydrogenophaga was higher than that in the model control group (p < 0.05). However, the abundance of Akkermansia and Coriobacteriaceae UCG-002 was significantly lower than that of the model control group (p < 0.05). Conclusions: BDE-47 induces diabetogenic dysbiosis in prediabetic mice, which is reversible by dietary interventions. These findings suggest that microbiota-targeted strategies may effectively mitigate the diabetes risk associated with environmental pollutant exposure. Future studies should further explore the mechanisms underlying these microbiota changes and the long-term health benefits of such interventions. Full article

Postbiotics, defined as metabolites produced by probiotics, encompass both bacterial cells and their metabolic byproducts, and offer significant health benefits to the host. However, there are relatively few reports on their effects on intestinal microbiota. In this study, we investigated the components, total antioxidant capacity of Lactobacillus helveticus postbiotics (LHPs) and their impact on intestinal flora using the Simulator for Human Intestinal Microecology Simulation (SHIME). The results indicate that the primary components of postbiotics include polysaccharides, proteins, and organic acids. Furthermore, LHPs have a strong ability to inhibit the growth of harmful bacteria while promoting the growth of probiotics. Additionally, LHPs significantly increased the total antioxidant capacity in the intestine and regulated the balance of intestinal microbiota. Notably, there was also a significant increase in the content of short-chain fatty acids (SCFAs) in the intestine. Overall, LHPs have the potential to aid in the prevention and treatment of diseases by enhancing gut microbiology. Full article

Background/Objectives: Selective serotonin reuptake inhibitors (SSRIs), widely prescribed for anxiety disorders, may negatively impact the gut microbiota, contributing to dysbiosis. Considering the gut–brain axis’s importance in mental health, probiotics could represent an effective adjunctive strategy. This study evaluated the effects of Lactobacillus helveticus R0052 and Bifidobacterium longum R0175 on microbiota composition, metabolic activity, and immune markers in fecal samples from patients with anxiety on SSRIs, using the SHIME^® (Simulator of the Human Intestinal Microbial Ecosystem) model. Methods: The fecal microbiotas of four patients using sertraline or escitalopram were inoculated in SHIME^® reactors simulating the ascending colon. After stabilization, a 14-day probiotic intervention was performed. Microbial composition was assessed by 16S rRNA sequencing. Short-chain fatty acids (SCFAs), ammonia, and GABA were measured, along with the prebiotic index (PI). Intestinal barrier integrity was evaluated via transepithelial electrical resistance (TEER), and cytokine levels (IL-6, IL-8, IL-10, TNF-α) were analyzed using a Caco-2/THP-1 co-culture system. The statistical design employed in this study for the analysis of prebiotic index, metabolites, intestinal barrier integrity and cytokines levels was a repeated measures ANOVA, complemented by post hoc Tukey’s tests to assess differences across treatment groups. For the 16S rRNA sequencing data, alpha diversity was assessed using multiple metrics, including the Shannon, Simpson, and Fisher indices to evaluate species diversity, and the Chao1 and ACE indices to estimate species richness. Beta diversity, which measures microbiota similarity across groups, was analyzed using weighted and unweighted UniFrac distances. To assess significant differences in beta diversity between groups, a permutational multivariate analysis of variance (PERMANOVA) was performed using the Adonis test. Results: Probiotic supplementation increased Bifidobacterium and Lactobacillus, and decreased Klebsiella and Bacteroides. Beta diversity was significantly altered, while alpha diversity remained unchanged. SCFA levels increased after 7 days. Ammonia levels dropped, and PI values rose. TEER values indicated enhanced barrier integrity. IL-8 and TNF-α decreased, while IL-6 increased. GABA levels remained unchanged. Conclusions: The probiotic combination of Lactobacillus helveticus R0052 and Bifidobacterium longum R0175 modulated gut microbiota composition, metabolic activity, and inflammatory responses in samples from individuals with anxiety on SSRIs, supporting its potential as an adjunctive strategy to mitigate antidepressant-associated dysbiosis. However, limitations—including the small pooled-donor sample, the absence of a healthy control group, and a lack of significant GABA modulation—should be considered when interpreting the findings. Although the SHIME^® model is considered a gold standard for microbiota studies, further clinical trials are necessary to confirm these promising results. 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

The balance between physiological, psychological, and environmental factors often shapes human experience. In recent years, research has drawn attention to the gut microbiota as a significant contributor to brain function and emotional regulation. This narrative review examines how changes in gut microbiota may relate to depression. We selected studies that explore the link between intestinal dysbiosis and mood, focusing on mechanisms such as inflammation, vagus nerve signaling, HPA axis activation, gut permeability, and neurotransmitter balance. Most of the available data come from animal models, but findings from human studies suggest similar patterns. Findings are somewhat difficult to compare due to differences in measurement procedures and patient groups. However, several microbial shifts have been observed in people with depressive symptoms, and trials with probiotics or fecal microbiota transplant show potential. These results remain limited. We argue that these interventions deserve more attention, especially in cases of treatment-resistant or inflammation-driven depression. Understanding how the gut and brain interact could help define clearer subtypes of depression and guide new treatment approaches. Full article

Alzheimer’s Disease (AD) is a multifactorial process. Amyloid plaque formation constitutes the main characteristic of the disease. Despite the identification of numerous factors associated with AD, the mechanism remains unclear in several aspects. Disturbances in intestinal and blood–brain barrier (BBB) penetration, observed in AD, may facilitate immunologic response to food-derived antigens. In the present study, antibodies against egg albumin, bovine-casein, and N-Glycolyl-Neuraminic acid (Neu5Gc) were measured in the cerebrospinal fluid (CSF) and serum of the patients using an enzyme-linked immunosorbent assay (ELISA). Zero anti-Neu5Gc and low concentrations of anti-casein antibodies were detected. Increased anti-native egg albumin antibodies were present in the serum of patients of all stages with 65% positivity (p < 0.001) in mild disease and a higher percentage in females (81.9%, p < 0.001). Lower serum positivity to anti-denatured egg albumin antibodies was observed, showing a gradual increase with severity and higher prevalence also in females. In the CSF, anti-native and anti-denatured egg albumin antibodies were mainly observed in severely ill patients with accumulative positivity to either antigen, reaching 61.8% in severe vs. 15% in mild disease (p < 0.001). Increased values were mainly observed in males. Anti-egg albumin antibodies may be implicated in the disease mechanism through sequence/structural similarity with human proteins, mainly serpins, and it would be worth consideration in further investigations and therapeutic strategies. Full article

Mycotoxins represent a group of highly toxic secondary metabolites produced by diverse fungal pathogens. Mycotoxin contaminations frequently occur in foods and feed and pose significant risks to human and animal health due to their carcinogenic, mutagenic, and immunosuppressive properties. Notably, deoxynivalenol, zearalenone, fumonisins (mainly including fumonisins B1, B2, and FB3), aflatoxin B1 (AFB1), and T-2/HT-2 toxins are the major mycotoxin contaminants in foods and feed. Undoubtedly, exposure to these mycotoxins can disrupt gut health, particularly damaging the intestinal epithelium in humans and animals. In this review, we summarized the detrimental effects caused by these mycotoxins on the intestinal health of humans and animals. The fundamental molecular mechanisms, which cover the induction of inflammatory reaction and immune dysfunction, the breakdown of the intestinal barrier, the triggering of oxidative stress, and the intestinal microbiota imbalance, were explored. These signaling pathways, such as MAPK, Akt/mTOR, TNF, TGF-β, Wnt/β-catenin, PKA, NF-kB, NLRP3, AHR, TLR2, TLR4, IRE1/XBP1, Nrf2, and MLCK pathways, are implicated. The abnormal expression of micro-RNA also plays a critical role. Finally, we anticipate that this review can offer new perspectives and theoretical foundations for controlling intestinal health issues caused by mycotoxin contamination and promote the development of prevention and control products. Full article