Expression Of Junction Proteins Research Articles

Polysaccharides derived from golden mushroom (Cantharellus cibarius Fr.) modulate gut microbiota and enhance intestinal barrier function to ameliorate dextran sulfate sodium-induced colitis in mice

IntroductionInflammatory bowel disease (IBD), including ulcerative colitis, is marked by intestinal barrier disruptions, immune system dysregulation, and an imbalance in the gut microbiota. The golden chanterelle mushroom, Cantharellus cibarius Fr., a popular edible mushroom, has shown potential therapeutic benefits. This study examines the therapeutic potential of a crude polysaccharide extract obtained from C. cibarius Fr. (CCP) on intestinal barrier integrity, inflammatory cytokine levels, and gut microbiota composition in a murine model of colitis induced by dextran sulfate sodium (DSS).MethodsTo induce colitis BALB/c mice were provided to consume autoclaved water with 3% DSS for 7 days, followed by 14 days of CCP supplementation. To assess the effects of CCP, histological analysis of colon tissue was performed, gene expression, inflammatory responses, tight junction proteins expression, gut barrier integrity, and cytokines levels were measured and analyzed and 16S rRNA sequencing were evaluated.Results and DiscussionCCP treatment alleviates colitis symptoms by improving body weight, and enhancing intestinal integrity through increased mucin-2 and tight junction protein expression. Additionally, CCP administration regulates the altered immune response by mitigating the expression of pro-inflammatory cytokines and upregulating anti-inflammatory cytokines. Furthermore, CCP supplementation effectively modulates DSS-induced dysbiosis as demonstrated by 16S rRNA sequencing results. These findings suggest that crude polysaccharides from the golden chanterelle mushroom, C. cibarius Fr., hold promise for treating colitis, via strengthening the intestinal barrier, regulating inflammatory responses, and reshaping the gut dysbiosis in a DSS-induced colitis model. CCP offers a novel approach for managing colitis, as a chronic inflammatory condition.

Fucoidan-Mediated Covalent Modification Mitigates Allergenicity of Shrimp (Penaeus vannamei) in Mice via Enhanced Intestinal Barrier Function and Antigen Presentation Suppression.

Covalent modification is an effective strategy for reducing the allergenicity of single allergens. However, due to the complexity of the food matrix, its application in hypoallergenic food production requires further exploration. The study showed that covalent modification of fucoidan decreased the specific antibody levels, inhibited Th2 cell differentiation, and reduced mast cell degranulation, suggesting that it significantly reduced the allergenicity of Penaeus vannamei. Further analysis showed that covalent modification not only up-regulated the intestinal tight junction proteins expression and improved intestinal mucus secretion but also restored intestinal microbial homeostasis by immunological and 16S rRNA gene sequencing. Additionally, covalent modification inhibited dendritic cell maturation and CD8+ T cell differentiation, thereby reducing antigen recognition and presentation, as determined by transcriptome and flow cytometry. Therefore, the covalent modification of fucoidan reduced shrimp allergenicity by enhancing intestinal barrier function and inhibiting antigen presentation. In conclusion, it is a potential strategy for processing hypoallergenic foods.

Wolfberry Honey and Its Extract Alleviate Dextran Sodium Sulfate-Induced Ulcerative Colitis by Improving Intestinal Barrier Function and Reducing Oxidative Stress and Inflammation.

Inflammatory bowel disease (IBD) is a chronic condition characterized by gut inflammation causing persistent diarrhea and abdominal pain. Despite the nutritional benefits of wolfberry honey (from Lycium barbarum L.), its potential to alleviate IBD remains underexplored. This study evaluated the protective effects of wolfberry honey and its extract (wolfberry honey extract [WHE]) against dextran sulfate sodium (DSS)-induced ulcerative colitis (UC) using in vivo and in vitro models. Mice pretreated with wolfberry honey showed significant symptom improvement in DSS-induced UC, linked to reduced expression of proinflammatory markers (Il-1β, Il-6, Tnf-α, and Mcp-1) and increased antioxidant genes (Nrf2, Sod2). Increased Occludin levels indicated improved intestinal barrier function. In vitro, WHE protected DSS-treated Caco-2 cells by lowering reactive oxygen species (ROS), stabilizing mitochondrial membrane potential, and inhibiting TLR4/NF-κB signaling. It enhanced the expression of antioxidant genes and tight junction proteins (ZO-1, Occludin, and Claudin-1). Metabolomic analysis revealed that WHE modulated glycerophospholipid metabolism, increasing phosphatidylcholine and choline levels and decreasing lysophosphatidylcholine levels. These results highlight the potential of wolfberry honey and its extract as nutraceuticals for managing UC through their effects on inflammation, oxidative stress, and intestinal barrier function. Further research is warranted to elucidate their mechanisms of action and assess their long-term therapeutic benefits in IBD management.

In Vitro Protective Effects of a Standardized Extract of Opuntia ficus-indica (L.) Mill. Cladodes and Olea europaea L. Leaves Against Indomethacin-Induced Intestinal Epithelial Cell Injury

Nonsteroidal anti-inflammatory drugs (NSAIDs) can induce serious adverse effects in gastrointestinal (GI) mucosa, increasing intestinal permeability and leading to mitochondrial dysfunction, oxidative stress, apoptosis and inflammation. As proton pump inhibitors are effective in protecting against NSAID-induced gastropathy but not NSAID-induced enteropathy, current research is focused on natural products as protective substances for therapy and prevention of intestinal injury. Herein, through the use of an in vitro model based on intestinal epithelial cell (Caco-2) damage caused by indomethacin (INDO), we examined the protective activity of a commercially available standardized extract (OFI+OE) from Opuntia ficus-indica (L.) Mill. cladodes and Olea europaea L. leaves. Pre-treatment with OFI+OE prevented INDO-induced intestinal epithelial barrier damage, as demonstrated by TEER measurement, fluorescein permeability, and tight junction protein expression. The extract showed positive effects against INDO-induced oxidative stress and correlated activation of apoptosis, decreasing pro-apoptotic markers BAX and Caspase-3 and increasing anti-apoptotic factor Bcl-2. Moreover, the extract inhibited the NF-κB pathway and pro-inflammatory cascade. In conclusion, these data support the use of OFI+OE extract as a natural strategy for therapy and prevention of intestinal mucosal damage, demonstrating its beneficial effects against INDO-induced intestinal damage, through modulation of oxidative, apoptotic, and inflammatory pathways.

Quercetin alleviates ulcerative colitis through inhibiting CXCL8-CXCR1/2 axis: a network and transcriptome analysis

IntroductionUlcerative colitis (UC) is a chronic inflammatory condition of the intestinal tract in which mucosal healing is a crucial measure of therapeutic efficacy. Quercetin, a flavonoid prevalent in various foods and traditional Chinese medicines, exhibits notable pharmacological properties, including antioxidant and anti-inflammatory activities. Consequently, it warrants investigation to determine its potential therapeutic effects on UC. The objective of this study was to investigate the effects and underlying mechanisms of quercetin in a murine model of UC.MethodsA comprehensive approach integrating network predictions with transcriptomic analyses was employed to identify the potential targets and enriched pathways associated with quercetin in UC. Subsequently, the effects of quercetin on pathological morphology, inflammatory mediators, and mucosal barrier-associated proteins, as well as the identified potential targets and enriched pathways, were systematically investigated in a murine model of dextran sulfate sodium (DSS)-induced UC.ResultsNetwork analyses identified CXCL8 and its receptors, CXCR1 and CXCR2, as primary target genes for therapeutic intervention in UC. Further validation through transcriptomic analysis and immunofluorescence staining demonstrated significant upregulation of the CXCL8-CXCR1/2 axis in the intestinal tissues of patients with UC. Experimental investigations in animal models have shown that quercetin markedly alleviates DSS-induced symptoms in mice. This effect includes the restoration of colonic crypt architecture, normalization of goblet cell structure and density, reduction of inflammatory cell infiltration, and decreased concentrations of inflammatory mediators. Quercetin enhanced the expression of tight junction (TJ) proteins, including ZO-1, MUC2 (Mucin 2), and occludin, thereby preserving the integrity of the intestinal mucosal barrier. Additionally, it significantly diminished the levels of IL-17A, NF-κB, CXCL8, CXCR1, and CXCR2 in the colonic tissues of mice with UC.DiscussionThe ameliorative effects of quercetin on colon tissue damage in DSS-induced UC mice were significant, possibly due to its ability to inhibit the CXCL8-CXCR1/2 signaling axis. These findings provide a solid foundation for the clinical application and pharmaceutical advancement of quercetin.

Fructo-oligosaccharides Alleviated Ulcerative Colitis via Gut Microbiota-Dependent Tryptophan Metabolism in Association with Aromatic Hydrocarbon Receptor Activation in Mice.

Fructo-oligosaccharide (FOS) is a typical prebiotic with intestinal health-promoting effects. Here, we explored the anticolitis activity of FOS and clarified the underlying mechanisms. Dextran sulfate sodium (DSS)-induced mice were gavaged with FOS (400 mg/kg) for 37 days, and administration of FOS alleviated DSS-induced colitis symptoms. Besides, FOS improved gut microbiota dysbiosis and modulated the intestinal microbiota-controlled tryptophan metabolic pathways. Targeted metabolomic results showed that FOS significantly increased the colonic levels of indole-3-acetic acid (IAA) and indole-3-propionic acid (IPA) and subsequently increased the expressions of aromatic hydrocarbon receptors (AhR) in the colon and further promoted the expressions of interleukin-22 (IL-22) and intestinal tight junction proteins in the colitis mice. These findings for the first time highlight a novel anticolitis mechanism of FOS by alleviating intestinal microbiota dysbiosis and modulating microbial tryptophan metabolism to promote IAA and IPA production for triggering AhR/IL-22 axis activation.

The Anti-Inflammatory Properties of Polysaccharides Extracted from Moringa oleifera Leaves on IEC6 Cells Stimulated with Lipopolysaccharide In Vitro

Moringa oleifera (M. oleifera) is a plant with significant medicinal and nutritional value and contains various bioactive compounds, particularly in its leaves (MOL). This study sought to explore the impact of M. oleifera leaf polysaccharides (MOLPs) on lipopolysaccharide (LPS)-activated intestinal epithelial cells (IEC6) and to uncover the mechanisms involved. The cytotoxicity of MOLP on IEC6 cells was assessed using the Cell Counting Kit-8 (CCK-8) assay, which demonstrated a safe concentration range of 0–1280 µg/mL. The impact of MOLP on cell viability was further evaluated over 12 to 48 h. IEC6 cells were treated with three concentrations of MOLP low (25 µg/mL), medium (50 µg/mL), and high (100 µg/mL) alongside LPS (50 µg/mL) stimulation for one day. The findings revealed that treatment with MOLP significantly promoted cell migration and increased the production of interleukin-10 (IL-10), while it simultaneously decreased cell apoptosis and the levels of pro-inflammatory cytokines, such as tumour necrosis factor alpha (TNF-α), interleukin 1β (IL-1β), and interleukin 6 (IL-6). Additionally, MOLP treatments across all concentrations significantly reduced the expression of Toll-like receptor 4 (TLR-4), myeloid differentiation primary response 88 (MyD88), phosphorylated nuclear factor kappa B-alpha (pIκB-α), and phosphorylated NF-κB p65 signalling pathways. Moreover, MOLP restored the expression of tight junction proteins, such as zonula occludens-1 (ZO-1) and occludin, which had been disrupted by LPS. These results indicate that MOLP exhibits anti-inflammatory properties by inhibiting inflammatory signalling pathways and maintaining intestinal barrier integrity through the upregulation of tight junction proteins in IEC6 cells. This study enhances our understanding of the anti-inflammatory capabilities of MOLP.

Inhibitory mechanism of theaflavins on intestinal fluoride transport: a new insight from network pharmacology integrated transcriptomic analysis

Water and some foods are important sources of fluoride (F-) exposure, therefore, it is necessary to study intestinal F- absorption and its influencing factors to assess the benefits or risks of F- exposure. Our previous study found that theaflavins including theaflavin (TF), theaflavin-3-gallate (TF3G), theaflavin-3′-gallate (TF3′G) and theaflavin-3,3′-digallate (TFDG) could all significantly inhibit F- transport in Caco-2 monolayer models. However, information on its related mechanisms is still scarce. In this study, its related mechanisms were revealed by network pharmacology integrated transcriptomic analysis. A total of 27 candidate target proteins were screened by network pharmacology analysis for theaflavins inhibiting F- transport. Weighted gene co-expression network analysis (WGCNA) of transcriptome data identified three co-expression modules including 1422 genes. Further, 53 hub genes were screened by protein-protein interaction (PPI) network. Notably, MAPK8 (also called JNK1, c-Jun N-terminal kinase 1) was both a candidate target in network pharmacology analysis and a hub gene in WGCNA. The GO and KEGG results suggested that theaflavins inhibiting F- transport may be related to the MAPK signaling pathway. Further experiment showed that TF could reverse F--mediated activation in the JNK MAPK signaling pathway activation and increase in intracellular reactive oxygen species (ROS). In addition, we demonstrated that TF could restore the F--mediated in decreased expression and disorder of tight junction proteins, which ultimately inhibited F- transport. In conclusion, the inhibition of F- transport in Caco-2 monolayer models by theaflavins may be mediated via the ROS/JNK MAPK/tight junction signaling pathway.

6-shogaol attenuates cisplatin induced emesis by inhibiting the mtDNA-cGAS-STING signaling pathway in a rat pica model.

Ginger (Zingiber officinale Rosc.) is a traditional anti-emetic herb. 6-shogaol, the main active compound of ginger, is reported to possess a variety of bioactivities. This study aimed to investigate the anti-emetic effect of 6-shogaol in a cisplatin-induced pica rat model and explore its underlying mechanism. sThe rat pica model was established by intraperitoneal injection of cisplatin. The pathological damage of gastric antrum and ileum were observed by hematoxylin-eosin staining. The levels of serum 8-Hydroxy-desoxyguanosine (8-OHdG) were detected by ELISA. The expression of ZO1 tight junction protein (TJP-1) and occludin in ileum were determined by IHC. The levels of 8-oxo G DNA glycosylase 1 (OGG1), flap endonuclease 1 (FEN1), cyclic GMP-AMP synthase (cGAS), stimulator of interferon genes (STING), phospho-STING (p-STING), TANK binding kinase 1 (TBK1), phospho-TBK1 (pTBK1), nuclear factor kappa-B (NF-κB) and phospho-NF-κB (p-NF-κB) in gastric antrum and ileum were assayed by western blotting. We found that 6-shogaol significantly improved pica behavior in rats by downregulating NF-κB and IL-1β level, and ameliorating inflammatory damage in gastric antrum and ileum. Mechanistically, cGAS-STING axis activated by mtDNA is responsible for the cisplatin-induced gastrointestinal inflammatory responses. 6-Shogaol inhibited the mtDNA-cGAS-STING signaling pathway by increasing the level of base-excision repair enzyme OGG1 and decreasing the level of endonuclease FEN1. This study indicates that 6-shogaol has a therapeutic effect against chemotherapy-induced nausea and vomiting (CINV), potentially attributable to the suppression of the mtDNA-cGAS-STING signaling pathway.

Lactic acid bacteria reduce polystyrene micro- and nanoplastics-induced toxicity through their bio-binding capacity and gut environment repair ability

Microplastics and nanoplastics (MNPs) are emerging environmental contaminants that have received significant attention in recent years. Currently, there are more studies on the toxic effects of MNPs exposure on animals (especially aquatic organisms and mammals), but data on the reduction of toxic effects caused by MNPs exposure are still very limited. Lactic acid bacteria (LAB), recognized as safe food-grade microorganisms, possess the capability to bioconjugate harmful substances. In this experiment, we chose lactic acid bacteria (LAB) with different binding capacities to MNPs in vitro to intervene in MNPs-exposed mice to investigate the reducing effect on the toxicity caused by MNPs exposure. Our study showed that LAB with a high intercalation capacity with MNPs in vitro were more effective in alleviating the toxicity caused by MNPs exposure. Notably, Lactobacillus plantarum DT22, despite its low inter-adsorption with MNPs, played a pivotal role in upregulating the relative expression of tight junction proteins and modulating the intestinal microbiota. Thus, LAB strains' mitigation of MNPs toxicity extends beyond bio-binding; their capacity to repair the damaged gut environment is also crucial. LAB strains are proposed as a dietary intervention to reduce MNPs-induced toxicity.

Clinically relevant cell culture model of inflammatory bowel diseases for identification of new therapeutic approaches.

Inflammatory Bowel Diseases (IDB) are chronic disorders characterized by gut inflammation, mucosal damage, increased epithelial permeability and altered mucus layer. No accurate in vitro model exists to simulate these characteristics. In this context, drug development for IBD or intestinal inflammation requires in vivo evaluations to verify treatments efficacy. A new model with altered mucus layer composition; altered epithelial permeability and pro-inflammatory crosstalk between immune and epithelial cells will be developed to enhance in vitro models for studying IBD treatments. The effects of dextran sulfate sodium and/or lipopolysaccharides on intestinal permeability, cytokines synthesis (IL-6, IL-8, TNF-α and IL-1β), mucins (MUC2, MUC5AC) and tight junction proteins expression (Claudin-1, ZO-1 and Occludin) were investigated in a tri-coculture model combining differentiated Caco-2/HT29-MTX cells and THP-1 cells. Two anti-inflammatory agents were evaluated to assess the model's therapeutic strategy applicability (corticoids and pro-resolving factors). Two in vitro models have been developed. The first model, characterized by increased permeability of the epithelial layer and subsequent secretion of inflammatory cytokines, can reproduce the different phases of inflammation, and enables the evaluation of preventive treatments. The second model simulates the acute phase of inflammation and allows for the assessment of curative treatments. Both models demonstrated reversibility when treated with betamethasone and pro-resolving factors. These in vitro models are valuable for selecting therapeutic agents prior to their application in in vivo models. They enable the assessment of agents' anti-inflammatory effects and their ability to permeate the inflamed epithelial layer and interact with immune cells.

IL-1β-induced pericyte dysfunction with a secretory phenotype exacerbates retinal microenvironment inflammation via Hes1/STAT3 signaling pathway

Retinal pericytes are mural cells surrounding capillaries to maintain the integrity of blood-retina barrier and regulate vascular behaviors. Pericyte loss has been considered as the hallmark of diabetic retinopathy (DR), which is a major complication of diabetes and the leading cause of blindness in adults. However, the precise function of pericytes in regulating the retinal microenvironment and the underlying mechanism remains largely unknown. In this study, we observed a secretory phenotype of pericytes with elevated inflammatory cytokines in response to Interleukin-1β (IL-1β), a canonical inflammatory cytokine which significantly increases during the initial stages of diabetic retinopathy. This phenotype is also accompanied by reduced expression of adherent junction proteins and contractile proteins. Paracrine cytokines derived from pericytes further induce the chemotaxis of microglia cells and trigger detrimental changes in endothelial cells, including reduced expression of tight junction protein Occludin and increased apoptosis. Mechanically, the secretion potential in pericytes is partially mediated by Hes1/STAT3 signaling pathway. Moreover, co-injection of stattic, an inhibitor targeting STAT3 activation, could effectively attenuate IL-1β-induced retinal inflammation and microglial activation in retina tissues. Collectively, these findings demonstrate the potential of retinal pericytes as an initial inflammatory sensor prior to their anatomical pathological loss, via undergoing phenotypic changes and secreting paracrine factors to amplify local inflammation and damage endothelial cells in vitro. Furthermore, inhibition of STAT3 activation by inhibitors significantly ameliorates IL-1β-induced retinal inflammation, suggesting STAT3 in retinal pericytes as a promising target for alleviating DR and other IL-1β-induced ocular diseases.

Recombinant Saccharomyces cerevisiae EBY100/pYD1-FaeG: a candidate for an oral subunit vaccine against F4+ ETEC infection.

Diarrheal diseases attributable to multidrug-resistant F4+ enterotoxigenic Escherichia coli (ETEC) are escalating in severity, posing significant risks to the health and safety of both humans and animals. This study used Saccharomyces cerevisiae EBY100 to display the FaeG subunit of F4 colonizing factor as an oral vaccine against F4+ ETEC infection. Mice were orally immunized twice with 108 CFU of EBY100/pYD1-FaeG, followed by a challenge with F4+ ETEC EC6 on day 7 post-immunization. The results showed that the recombinant strain EBY100/pYD1-FaeG orally enhanced the growth of the small intestine villi, significantly boosted the expression of tight junction proteins (ZO-1, Occludin, MUC2, and Claudin) (P < 0.05), and modulated the gut microbiota composition. Additionally, immunization with EBY100/pYD1-FaeG also upregulated the levels of IL-2, IL-4, and IFN-γ in the intestines of mice (P < 0.01), while serum IgG and fecal sIgA titer significantly increased (P < 0.05). These immune responses enhanced the capacity to fight against ETEC, leading to an increased survival rate of mice and relieved damage to tissues and organs of mice infection. In summary, the study suggested that the recombinant Saccharomyces cerevisiae EBY100/pYD1-FaeG could effectively stimulate the immune response and generate specific antibodies against F4+ ETEC, showing its potential to serve as a subunit oral vaccine candidate for preventing F4+ ETEC infection.IMPORTANCEThe multidrug-resistant F4+ enterotoxigenic Escherichia coli (ETEC) strains are the primary clinical pathogens responsible for post-weaning diarrhea in piglets, resulting in substantial economic losses in the pig farming industry. In the study, we developed an oral vaccine candidate, Saccharomyces cerevisiae EBY100/pYD1-FaeG, to prevent diarrhea caused by multidrug-resistant F4+ ETEC. Oral administration of EBY100/pYD1-FaeG significantly enhanced immune responses, improved intestinal health, and provided protection against F4+ ETEC infection in mice. This approach offers a potential application prospect for preventing F4+ ETEC infections that lead to post-weaning diarrhea in clinical settings and provides a promising solution for addressing the growing threat of antibiotic resistance in bacterial pathogens.

Long term Coptidis Rhizoma intake induce gastrointestinal emptying inhibition and colon barrier weaken via bitter taste receptors activation in mice

BackgroundCoptidis Rhizoma, a classic bitter traditional Chinese medicine, can lead to digestive dysfunction when long-term use according to traditional experience. Bitter taste receptors have been found to regulate gastrointestinal smooth muscle contraction. Coptidis Rhizoma alkaloids are potential agonists for bitter taste receptors, but whether they can induce gastrointestinal dysfunction via bitter taste receptors is not clear. PurposeThe purpose of this study is to elucidate whether long-term Coptidis Rhizoma decoction/berberine intake can affect gastrointestinal function via bitter taste receptors. MethodsFirstly, mice were orally administered Coptidis Rhizoma decoction (or berberine) for 8 weeks, then their appetite, gastrointestinal emptying function, colon barrier function, and gut microbiota homeostasis were evaluated. Subsequently, isolated intestine, molecular docking, calcium release, and immunofluorescence co-localization experiments were applied to explore the mechanism of Coptidis Rhizoma decoction (or berberine) inhibition effects on gastrointestinal motility. Finally, transmembrane resistance, scratch assay, tight junction and cytoskeletal protein immunofluorescence staining were conducted to verify that the bitter taste receptor is the target for Coptidis Rhizoma decoction (or berberine) to damage the colon barrier function. ResultLong-term Coptidis Rhizoma decoction (or berberine) intake can reduce appetite, inhibit gastrointestinal contractions, disrupt bacterial balance and colon barrier function in mice. Further mechanistic studies have shown that the alkaloids of Coptidis Rhizoma are agonists for bitter taste receptors, which can promote α-gustducin binding to CHRM3 by activating bitter taste receptors, finally inhibiting gastrointestinal smooth muscle contraction. In addition, Coptidis Rhizoma decoction (or berberine) can activate bitter taste receptors and its downstream pathways PKCβ/RhoA/ROCK1/MLC-2, reshape skeletal proteins, downregulate tight junction protein expression, and ultimately disrupt colon barrier function. ConclusionsLong term Coptidis Rhizoma intake induce gastrointestinal emptying inhibition and colon barrier weaken via bitter taste receptor activation in mice.

Perturbation of mammary epithelial cell apicobasal polarity by RHBDF1-facilitated nuclear translocation of PKCζ

BackgroundThe establishment of apicobasal polarity in epithelial cells is of critical importance in morphogenesis of mammary gland and other secretive gland tissues. The demise of the polarity is a critical step in early stages of tumorigenesis such as in breast ductal carcinoma in situ. The underlying molecular mechanism thus warrants in-depth investigations.ResultsProtein kinase C isoform ζ (PKCζ), which is highly expressed in breast cancer cells, accumulates in the nuclei of human mammary epithelial cells overexpressing human rhomboid family-1 (RHBDF1), an endoplasmic reticulum membrane protein. Nuclear translocation of PKCζ results in the failure of the formation of the cytosolic apicobasal polarity complex Par, of which PKCζ is an essential component. Additionally, enhanced nuclear translocation of PKCζ is accompanied by an inhibition of the expression of cell tight junction and adherens junction proteins and an increase of cell mobility. Mechanistically, RHBDF1 is able to interact with importin β1 and PKCζ and promote PKCζ phosphorylation. Consistently, treatment of RHBDF1-overexpressing cells with an inhibitor of PKCζ phosphorylation leads to restoration of apicobasal polarity and cell-cell junctions, as well as suppressed cell mobility.ConclusionsRHBDF1-facilitated nuclear translocation of PKCζ is critically responsible for the dismantlement of epithelial cell apicobasal polarity, and thus may serve as a target in the development of therapeutic approaches against early stages of breast cancer.

The protective effect of amitriptyline on experimental colitis through inhibiting TLR-4/MD-2 signaling pathway

Amitriptyline, a pleiotropic tricyclic antidepressant, possesses antioxidant and anti-inflammatory properties. Despite its diverse benefits, the specific effects of amitriptyline on inflammatory bowel disease (IBD) are not yet well defined. To explore this, we used a dextran sulfate sodium (DSS)–induced colitis model to examine the anti-inflammatory effects of amitriptyline and the underlying mechanisms by which it operates. Our research revealed that amitriptyline is effective in alleviating several pathological manifestations associated with colitis. This includes improving body weight retention, reducing disease activity index, lessening of colon length shortening, and repairing of colonic mucosal damage. Treatment with amitriptyline significantly protected mucosal injury by preserving the population of goblet cells and increasing the expression of tight junction proteins. Furthermore, we observed that amitriptyline effectively countered immune cell infiltration, specifically neutrophils and macrophages, while simultaneously lowering the levels of inflammatory cytokines such as tumor necrosis factor α, interleukin (IL)-1β, and IL-6. Additionally, RNA sequencing analysis pointed to the potential involvement of the Toll-like receptor (TLR) pathway in the anticolitic effects induced by amitriptyline. Subsequent Western blot analysis indicated that amitriptyline significantly inhibited the TLR-4–mediated nuclear factor (NF)-κB signaling pathway. To bolster our findings, in vitro studies demonstrated that amitriptyline downregulated the TLR-4/NF-κB/mitogen-activated protein kinase signaling cascades in mouse macrophages stimulated with lipopolysaccharide. Further molecular investigations revealed that amitriptyline was able to suppress the elevated expression of myeloid differentiation factor 2 that lipopolysaccharide stimulation typically induces. In summary, our findings suggest that amitriptyline effectively mitigates DSS–induced colitis in mice through the inhibition of TLR-4/myeloid differentiation 2 pathway signaling, indicating its potential repurposing for IBD treatment. Significance StatementThe potential of using amitriptyline in treating inflammatory bowel disease appears promising, leveraging its established safety and dosing profile as an antidepressant. The study results show that amitriptyline can alleviate pathological symptoms, inflammation, and intestinal mucosal damage in mice with colitis induced by DSS. The protective effect observed appears to be linked to the inhibition of TLR-4/myeloid differentiation 2 signaling pathway. By exploring novel applications for existing medications, we can optimize amitriptyline’s efficacy and broaden its impact in both medical and commercial contexts.

Elafibranor alleviates alcohol-related liver fibrosis by restoring intestinal barrier function.

We discuss the article by Koizumi et al published in the World Journal of Gastroenterology. Our focus is on the therapeutic targets for fibrosis associated with alcohol-related liver disease (ALD) and the mechanism of action of elafibranor (EFN), a dual agonist of peroxisome proliferator-activated receptor α (PPARα) and peroxisome PPAR δ (PPARδ). EFN is currently in phase III clinical trials for the treatment of metabolic dysfunction-associated fatty liver disease and primary biliary cholangitis. ALD progresses from alcoholic fatty liver to alcoholic steatohepatitis (ASH), with chronic ASH eventually leading to fibrosis, cirrhosis, and, in some cases, hepatocellular carcinoma. The pathogenesis of ALD is driven by hepatic steatosis, oxidative stress, and acetaldehyde toxicity. Alcohol consumption disrupts lipid metabolism by inactivating PPARα, exacerbating the progression of ALD. EFN primarily activates PPARα, promoting lipolysis and β-oxidation in ethanol-stimulated HepG2 cells, which significantly reduces hepatic steatosis, apoptosis, and fibrosis in an ALD mouse model. Additionally, alcohol disrupts the gut-liver axis at several interconnected levels, contributing to a proinflammatory environment in the liver. EFN helps alleviate intestinal hyperpermeability by restoring tight junction protein expression and autophagy, inhibiting apoptosis and inflammatory responses, and enhancing intestinal barrier function through PPARδ activation.

Bacillus velezensis HBXN2020 alleviates Salmonella Typhimurium infection in mice by improving intestinal barrier integrity and reducing inflammation

Bacillus velezensis is a species of Bacillus that has been widely investigated because of its broad-spectrum antimicrobial activity. However, most studies on B. velezensis have focused on the biocontrol of plant diseases, with few reports on antagonizing Salmonella Typhimurium infections. In this investigation, it was discovered that B. velezensis HBXN2020, which was isolated from healthy black pigs, possessed strong anti-stress and broad-spectrum antibacterial activity. Importantly, B. velezensis HBXN2020 did not cause any adverse side effects in mice when administered at various doses (1×107, 1×108, and 1×109 CFU) for 14 days. Supplementing B. velezensis HBXN2020 spores, either as a curative or preventive measure, dramatically reduced the levels of S. Typhimurium ATCC14028 in the mice’s feces, ileum, cecum, and colon, as well as the disease activity index (DAI), in a model of infection caused by this pathogen in mice. Additionally, supplementing B. velezensis HBXN2020 spores significantly regulated cytokine levels (Tnfa, Il1b, Il6, and Il10) and maintained the expression of tight junction proteins and mucin protein. Most importantly, adding B. velezensis HBXN2020 spores to the colonic microbiota improved its stability and increased the amount of beneficial bacteria (Lactobacillus and Akkermansia). All together, B. velezensis HBXN2020 can improve intestinal microbiota stability and barrier integrity and reduce inflammation to help treat infection by S. Typhimurium.

Bacillus velezensis HBXN2020 alleviates Salmonella Typhimurium infection in mice by improving intestinal barrier integrity and reducing inflammation.

Bacillus velezensis is a species of Bacillus that has been widely investigated because of its broad-spectrum antimicrobial activity. However, most studies on B. velezensis have focused on the biocontrol of plant diseases, with few reports on antagonizing Salmonella Typhimurium infections. In this investigation, it was discovered that B. velezensis HBXN2020, which was isolated from healthy black pigs, possessed strong anti-stress and broad-spectrum antibacterial activity. Importantly, B. velezensis HBXN2020 did not cause any adverse side effects in mice when administered at various doses (1×107, 1×108, and 1×109 CFU) for 14 days. Supplementing B. velezensis HBXN2020 spores, either as a curative or preventive measure, dramatically reduced the levels of S. Typhimurium ATCC14028 in the mice's feces, ileum, cecum, and colon, as well as the disease activity index (DAI), in a model of infection caused by this pathogen in mice. Additionally, supplementing B. velezensis HBXN2020 spores significantly regulated cytokine levels (Tnfa, Il1b, Il6, and Il10) and maintained the expression of tight junction proteins and mucin protein. Most importantly, adding B. velezensis HBXN2020 spores to the colonic microbiota improved its stability and increased the amount of beneficial bacteria (Lactobacillus and Akkermansia). All together, B. velezensis HBXN2020 can improve intestinal microbiota stability and barrier integrity and reduce inflammation to help treat infection by S. Typhimurium.

Ceftiofur induced intestinal flora disorder exacerbates liver toxicity via microbiota-gut-liver axis

As a common antibiotic, ceftiofur was widely used in animal husbandry. It is estimated that the consumption of ceftiofur (CEF) in animal production will continue to increase due to the role of promoting growth. Accumulating evidences showed that excessive supplementation of ceftiofur in feed disrupted the intestinal flora. However, the mechanism of liver injury caused by excessive supplementation of ceftiofur induced intestinal flora disturbance remains unclear. In this study, our finding indicated that excessive ceftiofur uptake significantly disrupted intestinal flora, which lead to serious liver injury through the gut-liver axis. Our results showed that CEF exposure causes significantly decreased the expression of jejunum tight junction proteins (ZO-1, Claudin, and Occludin); and reduced the number of intestinal goblet cells. In addition, excessive CEF uptake significantly promoted the expression of inflammatory-related proteins in jejunum. Meanwhile, 16s rDNA analysis found that CEF exposure disrupted the abundance of Lactobacillus, HT002, Escherichia-Shigella, Klebaiella, Enterococcus, and Citrobacter, thereby affecting metal iron binding, molecular function, and mitochondrial function in the liver. Furthermore, CEF exposure caused ferroptosis in hepatocytes, as shown by increased the expression of TFR1, FACL4, FLC, COX2, HMGB1, and TXNIP protein, and reduced the expression of GPX4, XCT, and Ferritin protein. These results suggest that the significant adverse impacts of excessive CEF supplementation on gut-liver axis in mice may increase the long-term risks related to liver diseases.