Impaired Intestinal Barrier Research Articles

Impact of Microcystin-LR exposure on biochemical responses, transcriptomic profiles, gut microbiota, and growth performance in grass carp (Ctenopharyngodon idella)

In recent years, Microcystin-LR (MC-LR) has been frequently detected in aquatic environments, exerting detrimental effects on the health of aquatic organisms. The grass carp (Ctenopharyngodon idella), an economically important fish, inhabits environments prone to MC-LR contamination. To investigate the toxicological mechanisms of MC-LR on grass carp, the fish were exposed to water containing 35.8 μg/L MC-LR. The physiological, biochemical, gut microbiota, and transcriptomic responses of the grass carp were evaluated at various time points (days 0, 1, 3, 7, and 21). The results showed that total superoxide dismutase activity in the liver and intestine was significantly increased after 21 days of exposure. Additionally, pathological damage was observed, including impaired intestinal epithelial barrier and nuclear pyknosis in the liver cell. MC-LR exposure also altered the diversity and composition of the gut microbiota and reshaped the microbiota interaction network, increasing the abundance of Cetobacterium and Vibrio by 32.43% and 25.7%, respectively. The intestinal microbiota functions were enriched in carbohydrate metabolism (10.45%) and amino acid metabolism (9.89%). RNA sequencing identified 504 shared differentially expressed genes (DEGs). The expression of the immune genes ITGB1 and GART was significantly upregulated in the D21 group. The upregulated DEGs were enriched in the complement and coagulation cascade pathways. MC-LR exposure induced metabolic disorders in grass carp, with upregulated genes significantly enriched in amino acid and carbohydrate metabolism pathways, while downregulated genes were enriched in lipid metabolism. This study provides valuable insights into the effects and toxicological mechanisms of MC-LR on aquatic organisms.

Bifidobacterium bifidum CCFM1163 Alleviates Cathartic Colon Through the Acetate/Propionate‐GPR41‐Gβγ Pathway

ABSTRACTCathartic colon, a form of slow‐transit constipation, arises from prolonged stimulant laxative use and is associated with intestinal barrier impairment and enteric nervous system damage. We identified Bifidobacterium bifidum CCFM1163 as an effective agent for alleviating cathartic colon; however, the underlying mechanisms remain unclear. This study first administered live, dead, and supernatant forms of CCFM1163 to cathartic colon mice, finding that only live bacteria were effective. Non‐targeted and targeted metabolomics analyses of mouse fecal metabolites highlighted short‐chain fatty acids (SCFAs) as key players. Animal experiments comparing the effects of major SCFAs revealed that acetic acid (AA) and propionic acid (PA) ameliorated cathartic colon (reduces intestinal transit time, p < 0.0001; increases fecal water content, p < 0.05). Inhibition studies using SCFAs receptor inhibitors and downstream inhibitors demonstrated that both HAS (a G protein‐coupled receptor 41 [GPR41] inhibitor) and Gallein (Gi protein βγ subunit [Gβγ] inhibitor) negated the reparative effects of CCFM1163 on the enteric nerves and intestinal barrier in cathartic colon mice. CCFM1163 was shown to modulate the intestinal flora, notably increasing Faecalibaculum, Candidatus Saccharimonas, and Prevotellaceae UCG‐001 (p < 0.05) and decreasing Escherichia, Clostridioides (p < 0.0001), while elevating AA and PA levels (p < 0.05). AAs act on the GPR41 receptor, activating the Gβγ, thus enhancing the intestinal barrier and reducing tissue inflammation. PA primarily repairs enteric nerves via GPR41‐Gβγ, promoting peristalsis. This study elucidates B. bifidum CCFM1163's potential mechanisms in cathartic colon relief and provides a theoretical basis for probiotic treatment.

A comparative study of the effects of crude chicory and inulin on gut health in weaning piglets

Dysfunction of the host-microbial balance and an impaired intestinal barrier can trigger inflammation and increase the antigen penetration. Inulin, commonly extracted from chicory root, is a prebiotic beneficial to gut health. The objective of this study was to compare the effect of chicory flour to inulin on gut health, few weeks after weaning. Two dose-dependent experiments (E1 and E2) were performed sequentially, each consisting of 80 castrated male piglets, weaned at day 21 and subsequently divided in 3 groups with ad libitum feed: control (Ctrl), inulin (INU) and crude chicory flour (CHI). For INU and CHI groups, a daily supplementation with the equated ‘inulin content’ increasing weekly was done by oral force-feeding, while the Ctrl groups received an isotonic sucrose solution. For E1, these doses were 1.5 g/day, 2 g/day and 2.5 g/day in W1, W2 and W3, respectively. For E2, these doses were 3 g/day, 4 g/day and 5 g/day in W1, W2 and W3, respectively. For each experiment at W0, W1 and W3, eight piglets per group were euthanized to assess gut structural and functional parameters. In E1, the CHI had lower average daily calorie intake (kcal/day) only at W3, while in E2 it was consistently lower than Ctrl and INU. In W3 of E2, CHI showed improved villi-to-crypt ratio and lower diarrhea occurrence than INU and Ctrl. Both supplemented groups in E2 showed higher butyrate production and lower D-xylose permeability (W3), compared to Ctrl. Interestingly, in E2, CHI had a more dominant effect on increasing the abundance of health promoting genera like Catenisphaera, Butyricicoccus, etc. and decreasing harmful genera like Erysipelotrichaceae_UCG-002 and Turicibacter. In E2, on W3 several inflammatory target genes (CXCL10, IL18, TNFα) and inflammation signalling genes (MyD88, NFκB1) were downregulated in ileum of INU and CHI. In colon, both chicory and inulin, proved to be beneficial, as the inflammation signalling and inflammatory targets genes NFκB1, DEFβ4A, TLR2 and IFNα were significantly downregulated. Therefore, crude chicory flour might also be a promising cost-effective alternative supplement to improve gut health in weaned piglets.

Polystyrene microplastics exposure: Disruption of intestinal barrier integrity and hepatic function in infant mice

The pervasive presence of microplastics (MPs) in infant formula and care products has emerged as a significant and underappreciated risk to public health. Notably, infants are at an elevated risk due to their underdeveloped intestinal defenses and liver detoxification capabilities, factors that could heighten their vulnerability to MPs. This study presents a comprehensive evaluation of the health implications linked to polystyrene microplastics (PSMPs) exposure during early life, examining both environmentally plausible and elevated levels. Based on histological analysis, in vivo imaging analysis, biochemical analysis and 16S rRNA sequencing results, our study found that oral PSMPs exposure in infant mice led to profound toxicological consequences, such as intestinal barrier impairment and hepatic injury, in a dose-dependent manner. Strikingly, even low ambient concentration of PSMPs (20 ppb) was sufficient to inflict considerable harm, disrupting the intestinal barrier, manifested that lessened mucus secretion, elevated iFABP level (276.50±10.73 pg/mL), decreased sIgA levels (0.60±0.03 mg/g), and pathological damage of intestinal tissues, allowing PSMPs accumulation and leakage into blood, inducing hepatotoxicity, such as increased TG levels (0.99±0.05 mmol/gprot) and lipid droplet accumulation. Furthermore, PSMPs exposure gives rise to aberrant bacterial colonization, dropping the abundance of probiotics as well as altering the abundance of pathogenic bacteria, which may contribute to the toxicity outcomes. The study underscores the critical need for vigilance regarding the insidious effects of PSMPs at environmental-relevant concentrations, especially in the context of infant exposure.

Tarm1 may affect colitis by regulating macrophage M1 polarization in a mouse colitis model.

In this study, we aimed to explore the role of Tarm1 in juvenile mice with dextran sulfate sodium (DSS)-induced colitis and elucidate the mechanisms that affect intestinal barrier function. A DSS-induced pediatric inflammatory bowel disease mouse model was established using 4-week-old juvenile mice. Disease activity index and histopathological damage scores were determined using hematoxylin and eosin (H&E) staining. Tarm1, F4/80, CD68, and CD86 levels were detected using qPCR, western blotting, and immunofluorescence. Trans epithelial electric resistance (TEER) was detected using the transwell assay. Results revealed that juvenile colitis mice fed 4% DSS drinking water had increased Tarm1 expression in the colon tissue, increased macrophage M1 polarization, higher expression of pro-inflammatory cytokines, and an impaired intestinal mucosal barrier, compared with the control group. Tarm1-knockdown RAW264.7 cells inhibited lipopolysaccharide (LPS)-induced M1 polarization and attenuated barrier damage in co-cultured intestinal epithelial cells. Tarm1 expression was increased in colonic tissues of juvenile mice with colitis, and LPS-induced M1 polarization and intestinal barrier damage were attenuated in Tarm1-knockdown RAW264.7 cells. This suggests that attenuation of Tarm1 expression is a potential target for pediatric inflammatory bowel disease therapy.

Effect of the Mediterranean diet on the faecal long-chain fatty acid composition and intestinal barrier integrity: an exploratory analysis of the randomised controlled LIBRE trial.

We recently showed that adherence to the Mediterranean diet increased the proportion of plasma n-3 PUFA, which was associated with an improved intestinal barrier integrity. In the present exploratory analysis, we assessed faecal fatty acids in the same cohort, aiming to investigate possible associations with intestinal barrier integrity. Women from the Lifestyle Intervention Study in Women with Hereditary Breast and Ovarian Cancer (LIBRE) randomised controlled trial, characterised by an impaired intestinal barrier integrity, followed either a Mediterranean diet (intervention group, n 33) or a standard diet (control group, n 35). At baseline (BL), month 3 (V1) and month 12 (V2), plasma lipopolysaccharide-binding protein, faecal zonulin and faecal fatty acids were measured. In the intervention group, faecal proportions of palmitoleic acid (16:1, n-7) and arachidonic acid (20:4, n-6) decreased, while the proportion of linoleic acid (18:2, n-6) and α linoleic acid (18:3, n-3) increased (BL-V1 and BL-V2, all P < 0·08). In the control group, faecal proportions of palmitic acid and arachidic acid increased, while the proportion of linoleic acid decreased (BL-V1, all P < 0·05). The decrease in the proportion of palmitoleic acid correlated with the decrease in plasma lipopolysaccharide-binding protein (ΔV1-BL r = 0·72, P < 0·001; ΔV2-BL r = 0·39, P < 0·05) and correlated inversely with adherence to the Mediterranean diet (Mediterranean diet score; ΔV1-BL r = -0·42, P = 0·03; ΔV2-BL r = -0·53, P = 0·005) in the intervention group. Our data show that adherence to the Mediterranean diet induces distinct changes in the faecal fatty acid composition. Furthermore, our data indicate that the faecal proportion of palmitoleic acid, but not faecal n-3 PUFA, is associated with intestinal barrier integrity in the intervention group.

Intestinal homeostasis disrupted by Periodontitis exacerbates Alzheimer’s Disease in APP/PS1 mice

Periodontitis exacerbates Alzheimer’s disease (AD) through multiple pathways. Both periodontitis and AD are intricately correlated to intestinal homeostasis, yet there is still a lack of direct evidence regarding whether periodontitis can regulate the progression of AD by modulating intestinal homeostasis. The current study induced experimental periodontitis in AD mice by bilaterally ligating the maxillary second molars with silk and administering Pg-LPS injections in APPswe/PS1ΔE9 (APP/PS1) mice. Behavioral tests and histological analyses of brain tissue were conducted after 8 weeks. Gut microbiota was analyzed and colon tissue were also evaluated. Then, fecal microbiota from mice with periodontitis was transplanted into antibiotic-treated mice to confirm the effects of periodontitis on AD and the potential mechanism was explored. The results indicated periodontitis exacerbated cognitive impairment and anxious behaviour in APP/PS1 mice, with increased Aβ deposition, microglial overactivation and neuroinflammation in brain. Moreover, the intestinal homeostasis of AD mice was altered by periodontitis, including affecting gut microbiota composition, causing colon inflammation and destroyed intestinal epithelial barrier. Furthermore, AD mice that underwent fecal transplantation from mice with periodontitis exhibited worsened AD progression and disrupted intestinal homeostasis. It also impaired intestinal barrier function, elevated peripheral inflammation, damaged blood-brain barrier (BBB) and caused neuroinflammation and synapses impairment. Taken together, the current study demonstrated that periodontitis could disrupt intestinal homeostasis to exacerbate AD progression potential via causing gut microbial dysbiosis, intestinal inflammation and intestinal barrier impairment to induce peripheral inflammation and damage BBB, ultimately leading to neuroinflammation and synapse impairment. It underscores the importance of maintaining both periodontal health and intestinal homeostasis to reduce the risk of AD.

Intestinal Barrier Impairment, Preservation, and Repair: An Update.

Our objective was to review published studies of the intestinal barrier and permeability, the deleterious effects of dietary components (particularly fat), the impact of altered intestinal permeability in disease models and human diseases, the role of the microbiome and epigenomics in control of barrier function, and the opportunities to restore normal barrier function with dietary interventions and products of the microbiota. We conducted a literature review including the following keywords alone or in combination: intestinal barrier, permeability, microbiome, epigenomics, diet, irritable bowel syndrome, inflammatory bowel disease, probiotics. Intestinal permeability is modified by a diet including fat, which increases permeability, and nutrients such as fiber, glutamine, zinc, vitamin D, polyphenols, emulsifiers, and anthocyanins, which decrease permeability. There is significant interaction of the microbiome and barrier function, including the inflammatory of luminal/bacterial antigens, and anti-inflammatory effects of commensals or probiotics and their products, including short-chain fatty acids. Epigenomic modification of barrier functions are best illustrated by effects on junction proteins or inflammation. Detailed documentation of the protective effects of diet, probiotics, prebiotics, and microbiota is provided. intestinal permeability is a critical factor in protection against gastrointestinal diseases and is impacted by nutrients that preserve or heal and repair the barrier and nurture anti-inflammatory effects.

Nicotinamide Alleviates Synergistic Impairment of Intestinal Barrier Caused by MC-LR and NaNO2 Coexposure.

Microcystin-LR (MC-LR) and nitrites from the environment and daily life can be ingested and absorbed by humans via the digestive tract. However, their combined effects on intestinal health remain unclear. Here, the combined impact of MC-LR and sodium nitrite (NaNO2) on the intestines of mice was investigated under actual human exposure conditions. After mice were exposed to MC-LR (10, 100 μg/L) and NaNO2 (30, 300 mg/L) individual and in combination for 6 months, it was found that MC-LR and NaNO2 synergistically decreased intestinal permeability and disrupted intestinal physical, chemical, immune, and microbial barriers. In the coexposure groups, the synergistic impairment to the intestinal barrier was noted with increasing concentrations of MC-LR or NaNO2, but this adverse effect was alleviated by nicotinamide supplementation. This study underscores the potential risks of simultaneous ingestion of MC-LR and nitrite on intestinal health. The protective role of nicotinamide suggests avenues for therapeutic intervention against environmental toxin-induced intestinal impairment.

Bile acid disorders and intestinal barrier dysfunction are involved in the development of fatty liver in laying hens

The pathogenesis of fatty liver is highly intricate. The role of the gut-liver axis in the development of fatty liver has gained increasing recognition in recent years. This study was conducted to explore the role of bile acid signaling and gut barrier in the pathogenesis of fatty liver. A total of 100 “Jing Tint 6” laying hens, 56-week-old, were used and fed basal diets until 60 weeks of age. At the end of the experiment, thirty individuals were selected based on the degree of hepatic steatosis. The hens with minimal hepatic steatosis (< 5 %) were chosen as healthy controls, while those with severe steatosis (> 33 %) in the liver were classified as the fatty liver group. Laying hens with fatty liver and healthy controls showed significant differences in body weight, liver index, abdominal fat ratio, feed conversion ratio (FCR), albumin height, Haugh unit, and biochemical indexes. The results of bile acid metabolomics revealed a clear separation in hepatic bile acid profiles between the fatty liver group and healthy controls, and multiple secondary bile acids were decreased in the fatty liver group, indicating disordered bile acid metabolism. Additionally, the mRNA levels of farnesoid X receptor (FXR) and genes related to bile acid transport were significantly decreased in both the liver and terminal ileum of hens with fatty liver. Moreover, the laying hens with fatty liver exhibited significant decreases in ileal crypt depth, the number of goblet cells, and the mRNA expression of tight junction-related proteins, alongside a significant increase in ileal permeability. Collectively, these findings suggest that disordered bile acids, suppressed FXR-mediated signaling, and impaired intestinal barrier function are potential factors promoting the development of fatty liver. These insights indicate that regulating bile acids and enhancing intestinal barrier function may become new preventive and therapeutic strategies for fatty liver in the near future.

6428 Update on Genetic F6428 actors of Nonalcoholic Fatty Liver Disease

Abstract Disclosure: H.M. Heshmati: None. Background: Nonalcoholic fatty liver disease (NAFLD) is a pandemic with a prevalence of 25% among the adult population worldwide. NAFLD is a spectrum of liver disorders ranging from simple steatosis to nonalcoholic steatohepatitis (NASH). NASH can progress to cirrhosis and hepatocellular cancer. The pathogenesis of NAFLD is complex and multifactorial, involving metabolic, epigenetic, and genetic factors. Several medical conditions (e.g., obesity, type 2 diabetes, inflammation, insulin resistance, disrupted gut microbiome, and impaired intestinal barrier function) are important risk factors associated with and/or contributing to NAFLD. This review presents an update on the genetic factors of NAFLD identified by the genome-wide association studies (GWAS). Methods: A systematic search of literature was conducted using the search terms nonalcoholic fatty liver disease, nonalcoholic steatohepatitis, cirrhosis, hepatocellular cancer, obesity, type 2 diabetes, epigenetics, and genetics. Results: Evidence for the contribution of genetic factors to NAFLD is further emphasized by the ethnic differences in the prevalence of NAFLD (e.g., higher prevalence among Hispanic American compared to African American adults). Based on the results of the GWAS, several genetic modifiers are relevant to NAFLD development and progression. They include variations in patatin-like phospholipase domain-containing protein 3 (PNPLA3), transmembrane 6 superfamily 2 (TM6SF2), membrane-bound O-acyltransferase domain-containing protein 7 (MBOAT7), glucokinase regulatory protein (GCKR), programmed cell death protein 1 (PDCD1), and hydroxysteroid 17β-dehydrogenase 13 (HSD17B13) genes (non-exhaustive list). These genetic modifiers interact with the metabolic and epigenetic factors for the development and progression of NAFLD and are responsible for the variability in the severity of NAFLD. The PNPLA3 gene variant (rs738409), which is the first and the best validated genetic modifier, is associated with a high risk of development and progression of NAFLD. The PDCD1 gene variant (rs7421861) is independently associated with hepatocellular cancer development. In contrast, the HSD17B13 gene variant (rs72613567) may have a protective effect for NAFLD risk. Conclusion: NAFLD is a multifactorial condition with a complex pathogenesis involving the interactions between metabolic, epigenetic, and genetic factors. The prevalence and risk of NAFLD differ across populations mainly due to genetic polymorphisms. Genetic factors relevant to NAFLD include variations in PNPLA3, TM6SF2, MBOAT7, GCKR, PDCD1, and HSD17B13 genes. A better understanding of these genetic modifiers and their mechanisms of action should allow a better risk prediction of the development of NAFLD and its progression to cirrhosis and hepatocellular cancer and help the development of new and selected therapies for NAFLD. Presentation: 6/3/2024

GZMA suppressed GPX4-mediated ferroptosis to improve intestinal mucosal barrier function in inflammatory bowel disease

BackgroundOur previous study has demonstrated a decreased colonic CD8+CD39+ T cells, enrichment of granzyme A (GZMA), was found in pediatric-onset colitis and inflammatory bowel disease (IBD) characterized by impaired intestinal barrier function. However, the influence of GZMA on intestinal barrier function remains unknown.MethodsWestern blotting(WB), real-time PCR (qPCR), immunofluorescence (IF) and in vitro permeability assay combined with intestinal organoid culture were used to detect the effect of GZMA on intestinal epithelial barrier function in vivo and in vitro. Luciferase, immunoprecipitation (IP) and subcellular fractionation isolation were performed to identify the mechanism through which GZMA modulated intestinal epithelial barrier function.ResultsHerein, we, for the first time, demonstrated that CD8+CD39+ T cells promoted intestinal epithelial barrier function through GZMA, leading to induce Occludin(OCLN) and Zonula Occludens-1(ZO-1) expression, which was attributed to enhanced CDX2-mediated cell differentiation caused by increased glutathione peroxidase 4(GPX4)-induced ferroptosis inhibition in vivo and in vitro. Mechanically, GZMA inhibited intestinal epithelial cellular PDE4B activation to trigger cAMP/PKA/CREB cascade signaling to increase CREB nuclear translocation, initiating GPX4 transactivity. In addition, endogenous PKA interacted with CREB, and this interaction was enhanced in response to GZMA. Most importantly, administration of GZMA could alleviate DSS-induced colitis in vivo.ConclusionThese findings extended the novel insight of GZMA contributed to intestinal epithelial cell differentiation to improve barrier function, and enhacement of GZMA could be a promising strategy to patients with IBD.

Coexistence of Celiac Disease and Allergic Wheat Sensitivity: An Observational Study of Daily Clinical Practice

Introduction: Although separate immunogenic mechanisms are involved, IgE-type sensitization to wheat and celiac disease (CD) may coexist. We observationally assessed the importance of this relationship in daily practice using CD and wheat sensitization screenings. Methods: Celiac antibody (CA) screening and food prick tests (FPTs) were requested simultaneously from patients who presented to the Allergy Clinic between January 2022 and December 2023 and had any complaint accompanied by CD symptoms/findings (non-celiac group). Patients with positive CA (CA+) underwent endoscopy. As another group, FPT results were recorded for patients previously diagnosed with CD following a gluten-free diet (celiac group). Results: In total, 169 patients (124 non-celiac and 45 celiac) were included in the study. Wheat prick positivity (WP+) was observed in 1 patient with CD. Among 65 WP+ patients without a CD diagnosis, 14 (20.3%) tested positive for CA+, and histopathology detected CD in 4 of these cases. Among the 59 WP– patients, 4 (8.8%) had CA+. The CA+ status of those with WP+ was significantly higher than those with WP– (p = 0.023). Conclusion: The 4 patients unaware of their CD exhibited WP+, with a higher rate of CA+ observed in the WP+ group. The association between WP+ and CA+ suggests that an impaired intestinal barrier may lead to simultaneous T helper 1 and 2 type inflammatory responses. Although different types of sensitization to the same food would not typically be expected, growing evidence indicates that this phenomenon does occur. Further studies are necessary to confirm these findings and to explore the underlying causes.

Epithelial neutrophil localization and tight junction Claudin-2 expression are innovative outcome predictors in inflammatory bowel disease.

Patients with inflammatory bowel disease (IBD) in clinical and endoscopic remission may still experience disease relapse. Therefore, there is a need to identify outcome predictors. Recently, the role of neutrophils in predicting outcomes in ulcerative colitis (UC) has been highlighted. Furthermore, the impairment of intestinal barrier plays a key role in forecasting disease outcomes in IBD. This observational study aimed to assess the predictive role of neutrophils according to tissue localization and intestinal barrier protein expression in IBD. IBD patients in clinical remission who underwent colonoscopy between January 2020 and June 2022 at two tertiary referral centres were enrolled. Patients with Mayo Endoscopic Score ≤1 (UC) and Simple Endoscopic Score ≤6 (Crohn's disease) were included. Histological activity was assessed using validated scores. Experienced pathologists evaluated neutrophil localization in the epithelium and lamina propria and immunohistochemical expression of Claudin-2 and junctional adhesion molecule A (JAM-A). Of 60 UC and 76 CD patients, 59.7% had histological activity. 25.8% of patients developed an adverse outcome within 12months. Neutrophils in the epithelium predicted adverse outcomes for UC (hazard ratio [HR] 5.198, p=0.01) and CD (HR 4.377, p=0.03) patients in endoscopic remission. Claudin-2 expression correlated with endoscopic and histological activity and predicted outcomes in UC. Similar results were found for JAM-A in CD despite this protein showing less specificity as a barrier predictor of outcome. This study highlights the potential role of epithelial neutrophil localization and Claudin-2 'leaky gut' expression as tools for predicting IBD outcomes and guiding further patient-tailored therapy.

Integrated Small Intestine Microbiota and Serum Metabolomics Reveal the Potential Mechanisms of Wine Steaming in Alleviating Rhubarb-Induced Diarrhea.

Long-term use of rhubarb (RH) commonly leads to diarrhea, which can be alleviated by steaming with wine. However, the specific mechanism by which wine steaming alleviates RH-induced diarrhea remains unknown. This study aims to reveal the underlying mechanisms of wine steaming in alleviating RH-induced diarrhea by examining small intestinal flora and serum metabolomics. Major anthraquinone and anthrone components were detected using ultra-performance liquid chromatography-mass spectrometry (UPLC-MS). Eighty-four ICR mice were randomly divided into control, RH, and RH steamed with wine (PRH) groups and were administered RH and PRH (1, 4, and 8 g/kg, i.g). for 14 consecutive days. Histopathological analysis was performed using hematoxylin-eosin staining. Levels of inflammatory factors and tight junction proteins, zonula occludens-1 (ZO-1) and occludin, in the small intestine were measured. The small intestine content was analyzed using 16S rRNA sequencing, and UPLC-MS was used to analyze endogenous metabolites. Levels of major anthraquinone and anthrone components decreased in PRH. Both RH and PRH groups showed varying degrees of loose stools and increased fecal water rates; the RH group exhibited more severe effects. Compared with the control group, RH caused small intestine injuries, increased levels of inflammatory cytokines, downregulated the expression of ZO-1 and occludin, and induced gut microbiota (GM) imbalance. The relative abundance of Lactobacillus decreased, while the relative abundance of Shigella and Streptococcus increased. However, PRH had a milder impact than RH. The glycerophospholipid metabolic pathway was involved in this effect. The levels of inflammatory cytokines and potential metabolites (sn-glycero-3-phosphoethanolamine) were positively correlated with Streptococcus infection, while the levels of ZO-1 and occludin were negatively correlated with Streptococcus infection. GM imbalance and abnormal glycerophospholipid metabolism contributed to impaired intestinal barrier function and inflammatory factor release, which may underlie RH-induced diarrhea, though PRH had a weaker effect. PRH alleviated RH-induced diarrhea by recovering GM balance, reducing ZO-1 and occludin expression, and decreasing the release of inflammatory factors. This mechanism may be linked to the reduced anthraquinone content. This study is the first to explore the mechanism of wine steaming in alleviating RH-induced diarrhea through small intestinal flora and serum metabolomics. It provides data to support the broader clinical use of RH and its safer application.

Impaired Intestinal Barrier Function in Immune Thrombocytopenic Purpura Patients Measured by Serum Zonulin

Abstract Background Besides its involvement in the digestion and resorption of nutrients, one task of the intestine is to act as a barrier regulating the passage of antigens and macromolecules from the environment into the organism. This barrier is to a major extent formed by the intestinal epithelia and its lateral tight junctions whichclose off the paracellular interstices. The tight junctions consist of transmembrane barrier proteins such as occludin and claudins, which are bound via proteins of the intracellular cytoskeleton with actin and microtubular structures. The function of the intestinal barrier (IB) can be modulated by a variety of stimuli. These include nutrients such as gluten, toxins or bacteria or their respective metabolic products ab- sorbed with the nutrition which induce a raised secretion of zonulin through the cells of the lamina propria. Objective To evaluate serum Zonulin level, as a marker of increased intestinal permeability, in ITP patient compared to healthy subjects. Methods This Study was conducted between October 2022 and June 2023 on 60 patients diagnosed with ITP divided in to 2 sub-groups 30 patients on steroid therapy for a duration longer than 3 months and 30 steroid naïve patients togetherwith 30 apparently healthy individuals as a control group. Patients were recruitedfrom Hematology department and outpatient clinic, Ain Shams University Hospitals. Results There was highly statistically significant difference between chronic patients and newly diagnosed patients regarding PLT and Serum Zonulin p &amp;lt; 0.001. There was highly statistically significant difference between recently diagnosed patients and healthy controls regarding PLT p &amp;lt; 0.001, there was statistically significant difference regarding ALT and Serum Zonulin, (p value were 0.03 and 0.01) respectively. There was a statistically significant correlation among all study participants between Serum Zonulin and Creatinine, p value = .004. There was no statistically significant correlation among all study participants between Serum Zonulin and TLC, HB, PLT and ALT, (p value were 0.736, 0.227, 070 and 0.619) respectively. There was highly statistically significant correlation between serum zonulin level and PLT in chronic patients, p value &amp;lt;0.001. Conclusion There was highly statistically significant difference between three study groups regarding PLT and Serum Zonulin. There was a statistically significant correlation among all study participants between Serum Zonulin and Creatinine. There was highly statistically significant correlation between serum zonulin level and PLT in chronic patients.

The neurotensin receptor 1 agonist PD149163 alleviates visceral hypersensitivity and colonic hyperpermeability in rat irritable bowel syndrome model.

An impaired intestinal barrier with the activation of corticotropin-releasing factor (CRF), Toll-like receptor 4 (TLR4), and proinflammatory cytokine signaling, resulting in visceral hypersensitivity, is a crucial aspect of irritable bowel syndrome (IBS). The gut exhibits abundant expression of neurotensin; however, its role in the pathophysiology of IBS remains uncertain. This study aimed to clarify the effects of PD149163, a specific agonist for neurotensin receptor 1 (NTR1), on visceral sensation and gut barrier in rat IBS models. The visceral pain threshold in response to colonic balloon distention was electrophysiologically determined by monitoring abdominal muscle contractions, while colonic permeability was measured by quantifying absorbed Evans blue in colonic tissue invivo in adult male Sprague-Dawley rats. We employed the rat IBS models, i.e.,lipopolysaccharide (LPS)- and CRF-induced visceral hypersensitivity and colonic hyperpermeability, and explored the effects of PD149163. Intraperitoneal PD149163 (160, 240, 320 μg kg-1) prevented LPS (1 mg kg-1, subcutaneously)-induced visceral hypersensitivity and colonic hyperpermeability dose-dependently. It also prevented the gastrointestinal changes induced by CRF (50 μg kg-1, intraperitoneally). Peripheral atropine, bicuculline (a GABAA receptor antagonist), sulpiride (a dopamine D2 receptor antagonist), astressin2-B (a CRF receptor subtype 2 [CRF2] antagonist), and intracisternal SB-334867 (an orexin 1 receptor antagonist) reversed these effects of PD149163 in the LPS model. PD149163 demonstrated an improvement in visceral hypersensitivity and colonic hyperpermeability in rat IBS models through the dopamine D2, GABAA, orexin, CRF2, and cholinergic pathways. Activation of NTR1 may modulate these gastrointestinal changes, helping to alleviate IBS symptoms.

A New Strategy for Dietary Nutrition to Improve Intestinal Homeostasis in Diarrheal Irritable Bowel Syndrome: A Perspective on Intestinal Flora and Intestinal Epithelial Interaction.

Although a reasonable diet is essential for promoting human health, precise nutritional regulation presents a challenge for different physiological conditions. Irritable Bowel Syndrome (IBS) is characterized by recurrent abdominal pain and abnormal bowel habits, and diarrheal IBS (IBS-D) is the most common, seriously affecting patients' quality of life. Therefore, the implementation of precise nutritional interventions for IBS-D has become an urgent challenge in the fields of nutrition and food science. IBS-D intestinal homeostatic imbalance involves intestinal flora disorganization and impaired intestinal epithelial barrier function. A familiar interaction is evident between intestinal flora and intestinal epithelial cells (IECs), which together maintain intestinal homeostasis and health. Dietary patterns, such as the Mediterranean diet, have been shown to regulate gut flora, which in turn improves the body's health by influencing the immune system, the hormonal system, and other metabolic pathways. This review summarized the relationship between intestinal flora, IECs, and IBS-D. It analyzed the mechanism behind IBS-D intestinal homeostatic imbalance by examining the interactions between intestinal flora and IECs, and proposed a precise dietary nutrient intervention strategy. This increases the understanding of the IBS-D-targeted regulation pathways and provides guidance for designing related nutritional intervention strategies.

A high cholesterol diet aggravates experimental colitis through SREBP2-modulated endocytosis and degradation of occludin and Zo-1 proteins.

Disrupted cholesterol homeostasis plays a critical role in the development of multiple diseases, such as cardiovascular disease and cancer. However, the role of cholesterol in inflammatory bowel disease (IBD) remains unclear. In the present study, we investigated whether and how high levels of cholesterol in the diet affect experimental colitis in mice. A normal diet supplemented with 1.25% cholesterol (high cholesterol diet) caused more severe colitis and aggravated the disruption of intestinal tight junction structure, accompanied by higher colonic tissue total cholesterol (TC) levels in a dextran sulfate sodium (DSS)-induced experimental colitis mouse model. Cholesterol aggravated DSS-induced intestinal epithelial barrier impairment and nuclear sterol regulatory element-binding protein 2 (nSREBP2) inhibition both in vivo and in vitro. In addition, nSREBP2 overexpression ameliorated cholesterol-induced intestinal epithelial barrier disruption in Caco2 cells. Interestingly, inhibition of SREBP2 disrupted intestinal epithelial barrier in the absence of cholesterol. Furthermore, SREBP2 regulated the protein expression of tight junction proteins (occludin/Zo-1) via modulating caveolin-1-mediated endocytosis and lysosomal degradation. Analysis of UK Biobank data indicated that, in fully adjusted models, higher serum TC concentrations were an independent protective factor for IBD incidence. The sterol regulatory element-binding factor 2 (SREBF2) gene rs2228313 (G/C) genetic variant was associated with the incidence of IBD and the CC genotype of SREBF2 rs2228313 was associated with higher serum TC levels and decreased the risk of IBD. In summary, a high cholesterol diet aggravates DSS-induced colitis in mice by down-regulating nSREBP2 expression, thereby promoting the endocytic degradation of tight junction proteins. In humans, SREBF2 gene single nucleotide polymorphism rs2228313 and serum TC levels are associated with IBD incidence.

Si-Ni-San ameliorates cholestatic liver injury by favoring P. goldsteinii colonization

Ethnopharmacological relevanceCurrent treatment options for cholestatic liver diseases are limited, and addressing impaired intestinal barrier has emerged as a promising therapeutic approach. Si-Ni-San (SNS) is a Traditional Chinese Medicine (TCM) formula commonly utilized in the management of chronic liver diseases. Our previous studies have indicated that SNS effectively enhanced intestinal barrier function through the modulation of gut microbiota. Aim of the studyThis study aims to verify the therapeutic effects of SNS on cholestatic liver injury, focusing on elucidating the underlying mechanism involving the gut-liver axis. Materials and methodsThe 16s RNA gene sequencing, non-targeted metabolomics were used to investigate the effects of SNS on the gut microbiota dysbiosis. Fecal microbiota transplantation (FMT) was conducted to identify potential beneficial probiotics underlying the therapeutic effects of SNS. ResultsOur results demonstrated that SNS significantly ameliorated cholestatic liver injury induced by partial bile duct ligation (pBDL). Additionally, SNS effectively suppressed cholestasis-induced inflammation and barrier dysfunction in both the small intestine and colon. While SNS did not impact the intestinal FXR-FGF15-hepatic CYP7A1 axis, it notably improved gut microbiota dysbiosis and modulated the profile of microbial metabolites, including beneficial secondary bile acids and tryptophan derivatives. Furthermore, gut microbiota depletion experiments and FMT confirmed that the therapeutic benefits of SNS in cholestatic liver disease are dependent on gut microbiota modulation, particularly through the promotion of the growth of potential probiotic P. goldsteinii. Moreover, a synergistic improvement in cholestatic liver injury was observed with the co-administration of P. goldsteinii and SNS. ConclusionOur study underscores that SNS effectively alleviates cholestatic liver injury by addressing gut microbiota dysbiosis and enhancing intestinal barrier function, supporting its rational clinical utilization. Furthermore, we highlight P. goldsteinii as a promising probiotic candidate for the management of cholestatic liver diseases.