Mechanism of cytokine modulation of epithelial tight junction barrier

Establishment of a 3D multi-layered in vitro model of inflammatory bowel disease

Crohn's Disease and Ulcerative Colitis, the main types of Inflammatory Bowel Disease (IBD), are life-threatening gastrointestinal disorders with no definitive cure. The establishment of biorelevant in vitro models that closely recapitulate the IBD microenvironment is of utmost importance to validate newly developed IBD therapies. To address the existing flaws in the current representation of the IBD microenvironment, we propose a novel three-dimensional (3D) in vitro model comprising a multi-layered gastrointestinal tissue with functional immune responses under inflammatory conditions. The multi-layered architecture consists of a lamina propria-like hydrogel with human intestinal fibroblasts (HIF), supporting an epithelial layer composed of Caco-2 and HT29-MTX cells, along with an endothelial layer surrogating the absorptive capillary network. A collagen-alginate composite matrix was optimized for the lamina propria-like hydrogel, preserving HIF metabolic activity and morphology over time. To achieve immune competence, pre-differentiated THP-1-derived macrophages were incorporated into the epithelial barrier. Inflammation was induced through the optimization of an inflammatory cocktail consisting of E. coli O111:B4 lipopolysaccharide combined with a specialized cytokine array (tumor necrosis factor-α, interferon-γ, and interleukin-1β). This inflammation-inducing stimulus led to a significant upregulation of pro-inflammatory cytokines commonly associated with IBD onset, including CCL20, IL-6, CXCL9 and CXCL10. Altogether, this 3D in vitro model has the potential to accelerate the drug development pipeline by providing reliable permeability and efficacy outputs for emerging therapies, reducing unnecessary animal experiments. Moreover, it offers a valuable in vitro platform for studying IBD pathophysiology and cell interplay dynamics.

Protective effects of insoluble dietary fiber from cereal bran against DSS-induced chronic colitis in mice: From inflammatory responses, oxidative stress, intestinal barrier, and gut microbiota

Insoluble dietary fiber (IDF) is a crucial component of cereals, and IDF from cereal bran (IDF-CB) has been reported to have multiple biological activities. However, the effect of IDF-CB on chronic colitis remains underexplored. The study aimed to investigate the impact of IDFs from wheat bran (WBIDF), rice bran (RBIDF), millet bran (MBIDF) and oat bran (OBIDF) on chronic colitis induced by dextran sulfate sodium (DSS). Our findings demonstrated that IDFs-CB supplementation mitigated DSS-induced weight loss and reduced lesions in the colon and spleen. Levels of proinflammatory cytokines (IL-1β, IL-6, IL-8, and TNF-α) and oxidative stress markers (MPO, iNOS and MDA)were decreased, and anti-inflammatory cytokine (IL-10) and T-SOD activity were increased after IDF-CB inclusion. Furthermore, IDFs-CB restored intestinal barrier function by regulating gene expression (up-regulated Muc-2, ZO-1 and Occludin, and down-regulated Claudin-1 and Claudin-4). Additionally, we analyzed the gut microbiota and SCFAs composition. WBIDF, MBIDF and OBIDF inhibited the growth of Muribaculaceae_unclassified, Bacteroides and Parasutterella. Conversely, IDFs-CB promoted the growth of Candidatus_Saccharimonas and norank_f__norank_o__Clostridia_UCG-014. Notably, WBIDF enhanced the abundance of Allobaculum, while MBIDF and OBIDF increased the abundance of Lachnospiraceae_NK4A136. Moreover, supplementation with IDFs-CB significantly elevated certain SCFA concentrations-particularly acetic acid and isohexanoic acid. Our results suggested that IDF-CB effectively alleviated DSS-induced chronic colitis; among them，WBIDF exhibited superior efficacy followed by OBIDF，MBIDF，and RBIDF. This study provides a theoretical foundation for dietary recommendations for patients suffering from inflammatory bowel disease.

Early weaning damages the intestinal epithelial barrier of squabs through toll-like receptor signaling pathways

Stress damage caused by early weaning and its possible mechanism have been studied mainly in young mammals, but rarely in altrices, especially in squabs. The study aimed to investigate the possible molecular mechanism of intestinal epithelial barrier damage caused by early weaning in squabs through determining the intestinal permeability, the ultrastructure of villous epithelium, the contents of ileal cytokines, and the protein relative expression of tight-junction proteins, TLRs and their mediated key factors in inflammatory signaling pathways. A total of 192 newly hatched squabs were randomly divided into 2 groups, 1 group was weaned and fed artificial pigeon milk from d 7, and the other group continued to be fed by the parent pigeons. The ileal mucosa and serum of 8 replicates were collected at 1, 4, 7, 10, and 14 d after weaning. The results indicated that early weaning could reduce the growth performance of squabs and damage the intestinal epithelial barrier, which is characterized by down-regulating the protein expression of claudin-1/3, up-regulating the protein expression of claudin-2, promoting the secretion of pro-inflammatory factors, inhibiting the secretion of anti-inflammatory factors, and increasing the permeability of the intestinal barrier. The specific mechanism of stress damage might be the activation of TLR2/4-MyD88-ERK/JNK inflammatory signaling pathway leading to the increase levels of IL-6 and TNF-α.

Synergistic fermentation of Cordyceps militaris and herbal substrates boosts grower pig antioxidant and immune function

BACKGROUND

Pathogenic infections can significantly impact the health of livestock. Traditionally, antibiotic growth promoters (AGPs) have been used in feed to enhance growth performance and disease control. However, concerns regarding antibiotic resistance have led to the exploration of traditional herbal medicine as a natural alternative, guided by the principle of medicine-food homology. The Taguchi method was employed to optimize the culture formula for cordycepin production, an active component of Cordyceps militaris (C. militaris). The influences of C. militaris supplementing solid-state fermentation (CMSSF) in feed on the growth performance and immune responses of grower pigs were evaluated in the present study.

RESULTS

The C. militaris ethanol extract (CME) displayed potent free radical scavenging activity against 2, 2-Diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) after undergoing fermentation. Additionally, the antibacterial testing revealed that CME effectively inhibits the growth of common pig pathogens such as Glaesserella parasuis, Pasteurella multocida, Staphylococcus hyicus, and Streptococcus suis. In lipopolysaccharide (LPS)-treated intestinal porcine enterocyte cell line (IPEC-J2), CME significantly suppressed the production of pro-inflammatory cytokines, including tumor necrosis factor (TNF)-α and interleukin (IL)-6. In addition, higher antioxidative activity was detected as indicated by elevated concentration of superoxide dismutase (SOD) in pig serum. The levels of immunoglobulin M (IgM), IgA, and IgG antibodies, as well as classical swine fever virus (CSFV) antibodies (S/P ratio) in serum were all increased. Growth performance of pigs fed with dietary CMSSF supplementation was improved in comparison with the control.

CONCLUSIONS

Results demonstrated that CMSSF has the potential to be used as a natural growth promoter to enhance immunity, antioxidation, as well as overall health and growth performance of grower pigs.

Intragastric administration of short chain fatty acids greatly reduces voluntary ethanol intake in rats

Alcohol use disorder (AUD) represents a public health crisis with few FDA-approved medications for its treatment. Growing evidence supports the key role of the bidirectional communication between the gut microbiota and the central nervous system (CNS) during the initiation and progression of alcohol use disorder. Among the different protective molecules that could mediate this communication, short chain fatty acids (SCFAs) have emerged as attractive candidates, since these gut microbiota-derived molecules have multi-target effects that could normalize several of the functional and structural parameters altered by chronic alcohol abuse. The present study, conducted in male alcohol-preferring UChB rats, shows that the initiation of voluntary ethanol intake was inhibited in 85% by the intragastric administration of a combination of SCFAs (acetate, propionate and butyrate) given before ethanol exposure, while SCFAs administration after two months of ethanol intake induced a 90% reduction in its consumption. These SCFAs therapeutic effects were associated with (1) a significant reduction of ethanol-induced intestinal inflammation and damage; (2) reduction of plasma lipopolysaccharide levels and hepatic inflammation; (3) reduction of ethanol-induced astrocyte and microglia activation; and (4) attenuation of the ethanol-induced gene expression changes within the nucleus accumbens. Finally, we determined that among the different SCFAs evaluated, butyrate was the most potent, reducing chronic ethanol intake in a dose-response manner. These findings support a key role of SCFAs, and especially butyrate, in regulating AUD, providing a simple, inexpensive, and safe approach as a preventive and intervention-based strategy to address this devastating disease.

The Impact of NO2 on Epithelial Barrier Integrity of a Primary Cell-Based Air-Liquid Interface Model of the Nasal Respiratory Epithelium

Nitrogen dioxide (NO2) is a pervasive gaseous air pollutant with well-documented hazardous effects on health, necessitating precise toxicological characterization. While prior research has primarily focused on lower airway structures, the upper airways, serving as the first line of defense against airborne substances, remain understudied. This study aimed to investigate the functional effects of NO2 exposure alone or in combination with hypoxia as a secondary stimulus on nasal epithelium and elucidate its molecular mechanisms because hypoxia is considered a pathophysiological factor in the onset and persistence of chronic rhinosinusitis, a disease of the upper airways. Air-liquid interface cell cultures derived from primary nasal mucosa cells were utilized as an in vitro model, offering a high in vitro-in vivo correlation. Our findings demonstrate that NO2 exposure induces malfunction of the epithelial barrier, as evidenced by decreased transepithelial electrical resistance and increased fluorescein isothiocyanate (FITC)-dextran permeability. mRNA expression analysis revealed a significant increase in IL-6 and IL-8 expressions following NO2. Reduced mRNA expression of the tight junction component occludin was identified as a structural correlate of the damaged epithelial barrier. Notably, hypoxic conditions alone did not alter epithelial barrier integrity. These findings provide information on the harmful effects of NO2 exposure on the human nasal epithelium, including compromised barrier integrity and induction of inflammatory responses. Overall, this study contributes to our understanding of pathophysiological mechanisms underlying also upper airway respiratory diseases associated with air pollution exposure and emphasizes the importance of mitigating NO2 emissions to safeguard respiratory health.

Role of tight junction proteins in shaping the immune milieu of malignancies

INTRODUCTION

Tight junctions (TJs) and their constituent proteins play pivotal roles in cellular physiology and anatomy by establishing functional boundaries within and between neighboring cells. While the involvement of TJ proteins, such as claudins, in cancer is extensively studied, studies highlighting their interaction with immune system are still meager. Studies indicate that alterations in cytokines and immune cell populations can affect TJ proteins, compromising TJ barrier function and exacerbating pro-inflammatory conditions, potentially leading to epithelial cell malignancy. Disrupted TJs in established tumors may foster a pro-tumor immune microenvironment, facilitating tumor progression, invasion, epithelial-to-mesenchymal transition and metastasis. Although previous literature contains many studies describing the involvement of TJs in pathogenesis of malignancies their role in modulating the immune microenvironment of tumors is just beginning to be unleashed.

AREAS COVERED

This article for the first time attempts to discern the importance of interaction between TJs and immune microenvironment in malignancies. To achieve the above aim a thorough search of databases like PubMed and Google Scholar was conducted to identify the recent and relevant articles on the topic.

EXPERT OPINION

Breaking the vicious cycle of dysbiosis/infections/chemical/carcinogen-induced inflammation-TJ remodeling-malignancy-TJ dysregulation-more inflammation can be used as a strategy to complement the effect of immunotherapies in various malignancies.

The effect of Lonicerae flos and Rhizoma curcumae longae extract on the intestinal development and function of broilers

This study was conducted to explore effects of Lonicerae flos and Rhomoma curcumae longae extracts (LR) on intestinal function of broilers. Three hundred broiler chickens were randomly assigned to the following 5 groups. The control group were fed the basal diet; the antibiotic group were fed the basal diet supplemented with spectinomycin hydrochloride (50 million units/ton) + lincomycin hydrochloride (25 g/ton); the LRH, LRM and LRL groups were fed the basal diet supplemented with a high dose (750 g/ton of feed), normal dose (500 g/ton of feed), or low dose (250 g/ton of feed) of LR, respectively. The changes of intestinal structure, intestinal digestive enzyme activities, antioxidant enzyme activities, inflammatory cytokines, and bacterial abundances in the colon and cecum contents were determined. The results indicated that compared with the control group and the antibiotic group, LR significantly increased the villus length/crypt depth (VCR) of the intestine, and significantly inhibited oxidative stress and inflammatory responses in the broiler intestine. In addition, LR regulated intestinal function by increasing the abundance of the intestinal microorganisms in broilers. In conclusion, LR improved antioxidant capacity, intestinal morphology, and microorganisms, and inhibited inflammatory response. The effect of high and medium doses of LR was better than lower doses.

Fecal microbiota transplantation alleviates cognitive impairment by improving gut microbiome composition and barrier function in male rats of traumatic brain injury following gas explosion

Background

Dysbiosis of gut microbiota (GM) is intricately linked with cognitive impairment and the incidence of traumatic brain injury (TBI) in both animal models and human subjects. However, there is limited understanding of the impact and mechanisms of fecal microbiota transplantation (FMT) on brain and gut barrier function in the treatment of TBI induced by gas explosion (GE).

Methods

We have employed FMT technology to establish models of gut microbiota dysbiosis in male rats, and subsequently conducted non-targeted metabolomics and microbiota diversity analysis to explore the bacteria with potential functional roles.

Results

Hematoxylin-eosin and transmission electron microscopy revealed that GE induced significant pathological damage and inflammation responses, as well as varying degrees of mitochondrial impairment in neuronal cells in the brains of rats, which was associated with cognitive decline. Furthermore, GE markedly elevated the levels of regulatory T cell (Tregs)-related factors interleukin-10, programmed death 1, and fork head box protein P3 in the brains of rats. Similar changes in these indicators were also observed in the colon; however, these alterations were reversed upon transfer of normal flora into the GE-exposed rats. Combined microbiome and metabolome analysis indicated up-regulation of Clostridium_T and Allobaculum, along with activation of fatty acid biosynthesis after FMT. Correlation network analysis indirectly suggested a causal relationship between FMT and alleviation of GE-induced TBI. FMT improved intestinal structure and up-regulated expression of tight junction proteins Claudin-1, Occludin, and ZO-1, potentially contributing to its protective effects on both brain and gut.

Conclusion

Transplantation of gut microbiota from healthy rats significantly enhanced cognitive function in male rats with traumatic brain injury caused by a gas explosion, through the modulation of gut microbiome composition and the improvement of both gut and brain barrier integrity via the gut-brain axis. These findings may offer a scientific foundation for potential clinical interventions targeting gas explosion-induced TBI using FMT.

The role of the microbiota-gut-brain axis in methamphetamine-induced neurotoxicity: Disruption of microbial composition and short-chain fatty acid metabolism

Methamphetamine (METH) abuse is associated with significant neurotoxicity, high addiction potential, and behavioral abnormalities. Recent studies have identified a connection between the gut microbiota and METH-induced neurotoxicity and behavioral disorders. However, the underlying causal mechanisms linking the gut microbiota to METH pathophysiology remain largely unexplored. In this study, we employed fecal microbiota transplantation (FMT) and antibiotic (Abx) intervention to manipulate the gut microbiota in mice administered METH. Furthermore, we supplemented METH-treated mice with short-chain fatty acids (SCFAs) and pioglitazone (Pio) to determine the protective effects on gut microbiota metabolism. Finally, we assessed the underlying mechanisms of the gut-brain neural circuit in vagotomized mice. Our data provide compelling evidence that modulation of the gut microbiome through FMT or microbiome knockdown by Abx plays a crucial role in METH-induced neurotoxicity, behavioral disorders, gut microbiota disturbances, and intestinal barrier impairment. Furthermore, our findings highlight a novel prevention strategy for mitigating the risks to both the nervous and intestinal systems caused by METH, which involves supplementation with SCFAs or Pio.

Goat Milk Exosomes Ameliorate Ulcerative Colitis in Mice through Modulation of the Intestinal Barrier, Gut Microbiota, and Metabolites

Goat milk is rich in a variety of nutrients that are important for intestinal health and disease prevention. However, the role of exosomes in goat milk remains to be elucidated. This study investigated for the first time the therapeutic efficacy and molecular underlying mechanisms of mature milk exosomes (M-exo) and goat colostrum exosomes (C-exo) on dextran sodium sulfate-induced ulcerative colitis (UC) in mice. The findings demonstrate that M-exo and C-exo significantly improved physiological indices, suppressed the secretion of proinflammatory cytokines, and diminished oxidative stress and apoptosis in UC mice. Moreover, C-exo and M-exo restored the intestinal barrier function, remodeled the gut microbiota, and improved metabolite composition in the feces of colitis mice. In conclusion, goat milk exosomes ameliorate UC in mice, which provides a basis for the development of functional food applications for the prevention and treatment of inflammatory bowel disease.

Regulatory effects of the p38 mitogen-activated protein kinase-myosin light chain kinase pathway on the intestinal epithelial mechanical barrier and the mechanism of modified Pulsatilla decoction in the treatment of ulcerative colitis

OBJECTIVE

To investigate the mechanism of the protective effect of modified Pulsatilla decoction (, MPD) on the mechanical barrier of the ulcerative colitis (UC) intestinal epithelium in vitro and in vivo.

METHODS

We established an intestinal epithelial crypt cell line-6 cell barrier injury model by using lipopolysaccharide (LPS). The model was then treated with p38 mitogen-activated protein kinase-myosin light chain kinase (p38MAPK-MLCK) pathway inhibitors, p38MAPK-MLCK pathway silencing genes (si-p38MAPK, si-NF-κB, and si-MLCK), and MPD respectively. Transepithelial electronic resistance (TEER) measurements and permeability assays were performed to assess barrier function. Immunofluorescence staining of tight junctions (TJ) was performed. In in vivo experiment, dextran sodium sulfate-induced colitis rat model was conducted to evaluate the effect of MPD and mesalazine on UC. The rats were scored using the disease activity index based on their clinical symptoms. Transmission electron microscopy and hematoxylin-eosin staining were used to examine morphological changes in UC rats. Western blotting and real-time quantitative polymerase chain reaction were performed to examine the gene and protein expression of significant differential molecules.

RESULTS

In in vitro study, LPS-induced intestinal barrier dysfunction was inhibited by p38MAPK-MLCK pathway inhibitors and p38MAPK-MLCK pathway gene silencing. Silencing of p38MAPK-MLCK pathway genes decreased TJ expression. MPD treatment partly restored the LPS-induced decreased in TEER and increase in permeability. MPD increased the gene and protein expression of TJ, while down-regulated the LPS-induced high expression of p-p38MAPK and p-MLC. In UC model rats, MPD could ameliorate body weight loss and disease activity index, relieve colonic pathology, up-regulate TJ expression as well as decrease the expression of p-p38MAPK and p-MLC in UC rat colonic mucosal tissue.

CONCLUSIONS

The p38MAPK-MLCK signaling pathway can affect mechanical barrier function and TJ expression in the intestinal epithelium. MPD restores TJ expression and attenuates intestinal epithelial barrier damage by suppressing the p38MAPK-MLCK pathway.

Saccharomyces boulardii (CNCM I-745) alleviates collagen-induced arthritis by partially maintaining intestinal mucosal integrity through TLR2/MYD88/NF-κB pathway inhibition

BACKGROUND

Rheumatoid arthritis, a condition characterized by inflammation, has a substantial influence on both the worldwide economy and public health. Prior studies indicate that probiotics have the potential to enhance the composition of gut microbiota in instances of intestinal dysbiosis resulting from different disorders and contribute to the regulation of inflammation. The objective of this study is to investigate the impact of Saccharomyces boulardii on the gut microbiome in arthritis and its implications on inflammation.

METHODS

The study utilized the Collagen Induced Arthritis (CIA) Sprague-Dawley (SD) rat model. After administering Saccharomyces boulardii (150 mg/kg/day) six days a week and Methotrexate (MTX) (0.2 mg/week) treatment for eight weeks, microbial DNA from the feces was sequenced using 16S rRNA. The evaluation of histopathology, bone loss, and cartilage degradation was conducted using histology, immunohistology assays, and micro-computed tomography (µCT) examinations. The enzyme-linked immunosorbent assay (ELISA) was used to analyze proinflammatory cytokines, while the western blot technique was applied to detect protein in the gut and in cell lines. The quantification of gene expression in gut,joint and cell lines was performed using real-time polymerase chain reaction. The cell lines were activated and then treated with the culture supernatant of S. boulardii for an in vitro investigation. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) test was utilized to assess cell proliferationand viability. Cellular motility was measured in a wound healing experiment, whereas apoptotic proteins were analyzed using Western blotting.

RESULTS

S. boulardii has been found to enhance bone and joint integrity, modulate gut microbiota, and mitigate proinflammatory cytokine levels in rats with arthritis. It decreases the permeability of the intestines and promotes the production of gut tight-junction proteins. The administration of S. boulardii inhibits the proliferation of T-helper-17 (Th17) and Type 3 innate lymphoid cells (ILC3). Additionally, it elicits apoptosis in MH7A cell lines and hinders their migratory activity.

CONCLUSION

This study provides valuable insights into the therapeutic potential of S. boulardii for treating and preventing arthritis in rats with collagen-induced arthritis by modulating gut microbiota and inflammation.

IL-1 Receptor Contributes to the Maintenance of the Intestinal Barrier via IL-22 during Obesity and Metabolic Syndrome in Experimental Model

Intestinal permeability and bacterial translocation are increased in obesity and metabolic syndrome (MS). ILC3 cells contribute to the integrity of intestinal epithelium by producing IL-22 via IL-1β and IL-23. This study investigates the role of IL-1R1 in inducing ILC3 cells and conferring protection during obesity and MS. For this purpose, C57BL/6 wild-type (WT) and IL-1R1-deficient mice were fed a standard diet (SD) or high-fat diet (HFD) for 16 weeks. Weight and blood glucose levels were monitored, and adipose tissue and blood samples were collected to evaluate obesity and metabolic parameters. The small intestine was collected to assess immunological and junction protein parameters through flow cytometry and RT-PCR, respectively. The intestinal permeability was analyzed using the FITC-dextran assay. The composition of the gut microbiota was also analyzed by qPCR. We found that IL-1R1 deficiency exacerbates MS in HFD-fed mice, increasing body fat and promoting glucose intolerance. A worsening of MS in IL-1R1-deficient mice was associated with a reduction in the ILC3 population in the small intestine. In addition, we found decreased IL-22 expression, increased intestinal permeability and bacterial translocation to the visceral adipose tissue of these mice compared to WT mice. Thus, the IL-1R1 receptor plays a critical role in controlling intestinal homeostasis and obesity-induced MS, possibly through the differentiation or activation of IL-22-secreting ILC3s.

Quercetin Increases Growth Performance and Decreases Incidence of Diarrhea and Mechanism of Action in Weaned Piglets

This study aimed to investigate the mechanism of quercetin increasing growth performance and decreasing incidence of diarrhea in weaned piglets. Forty-eight Duroc × Landrace × Large White weaned piglets with similar body weight (7.48 ± 0.20 kg, 28 days of age) were randomly divided into four treatments (control, 250 mg/kg quercetin, 500 mg/kg quercetin, and 750 mg/kg quercetin treatments) and fed with basal diet or experimental diet supplemented with quercetin. Performance, diarrhea rate and index, and content of serum anti-inflammatory factors were determined and calculated in weaned piglets; colonic flora and signaling pathways related to anti-inflammation were measured using 16S rDNA sequencing and RNA-seq, respectively. The results showed that compared with control, feed-to-gain ratio and content of serum interferon gamma (IFN-γ) were significantly decreased in the 500 and 750 mg/kg quercetin treatments (P < 0.05); quercetin significantly decreased diarrhea rate and diarrhea index (P < 0.05) and significantly increased the content of serum transforming growth factor (TGF-β) in weaned piglets (P < 0.05); the content of serum NF-κB was significantly decreased in the 750 mg/kg quercetin treatment (P < 0.05); moreover, quercetin significantly increased diversity of colonic flora (P < 0.05), and at the phylum level, the relative abundance of Actinobacteria in the 500 and 750 mg/kg treatments was significantly increased (P < 0.05), and the relative abundance of Proteobacteria in the three quercetin treatments were significantly decreased (P < 0.05) in the colon of weaned piglets; at the genus level, the relative abundance of Clostridium-sensu-stricto-1, Turicibacter, unclassified_f_Lachnospiraceae, Phascolarctobacterium, and Family_XIII _AD3011_group was significantly increased (P < 0.05); the relative abundance of Subdollgranulum and Blautia was significantly decreased in the 500 and 750 mg/kg treatments (P < 0.05); the relative abundance of Eschericha-Shigella, Terrisporobacter, and Eubacterium-coprostanoligenes was significantly increased (P < 0.05); the relative abundance of Streptocococcus, Sarcina, Staphylococcus, and Ruminococcaceae_UCG-008 was significantly decreased in the three quercetin treatments (P < 0.05); the relative abundance of Ruminococcaceae_UCG_014 was significantly increased in the 250 mg/kg quercetin treatment in the colon of weaned piglets (P < 0.05). The results of Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis showed that differentially expressed genes (DEGs) from the quercetin treatments were significantly enriched in nuclear transcription factor-κB (NF-κB) signal pathway (P < 0.05); mRNA expression of tumor necrosis factor-α (TNF-α), interleukin-1R1 (IL-1R1), conserved helix-loop-helix ubiquitous kinase (CHUK), toll-like receptor 4 (TLR4), and IL-1β from quercetin treatments were significantly decreased in colonic mucosa of weaned piglets (P < 0.05). In summary, quercetin increased feed conversion ratio and decreased diarrhea through regulating NF-κB signaling pathway, controlling the balance between anti-inflammatory and proinflammatory factors, and modulating intestinal flora, thus promoting the absorption of nutrients in weaned piglets. These results provided the theoretical foundation for applying quercetin in preventing weaning piglets' diarrhea and animal husbandry practices.

Selected phytocannabinoids inhibit SN-38- and cytokine-evoked increases in epithelial permeability and improve intestinal barrier function in vitro

Irinotecan use is linked to the development of gastrointestinal toxicity and inflammation, or gastrointestinal mucositis. Selected phytocannabinoids have been ascribed anti-inflammatory effects in models of gastrointestinal inflammation, associated with maintaining epithelial barrier function. We characterised the mucoprotective capacity of the phytocannabinoids: cannabidiol, cannabigerol, cannabichromene and cannabidivarin in a cell-based model of intestinal epithelial stress occurring in mucositis. Transepithelial electrical resistance (TEER) was measured to determine changes in epithelial permeability in the presence of SN-38 (5 μM) or the pro-inflammatory cytokines TNFα and IL-1β (each at 100 ng/mL), alone or with concomitant treatment with each of the phytocannabinoids (1 μM). The DCFDA assay was used to determine the ROS-scavenging ability of each phytocannabinoid following treatment with the lipid peroxidant tbhp (200 μM). Each phytocannabinoid provided significant protection against cytokine-evoked increases in epithelial permeability. Cannabidiol, cannabidivarin and cannabigerol were also able to significantly inhibit SN-38-evoked increases in permeability. None of the tested phytocannabinoids inhibited tbhp-induced ROS generation. These results highlight a novel role for cannabidiol, cannabidivarin and cannabigerol as inhibitors of SN-38-evoked increases in epithelial permeability and support the rationale for the further development of novel phytocannabinoids as supportive therapeutics in the management of irinotecan-associated mucositis.

A derivative of 3-(1,3-diarylallylidene)oxindoles inhibits dextran sulfate sodium-induced colitis in mice

BACKGROUND

IA-0130 is a derivative of 3-(1,3-diarylallylidene)oxindoles, which is a selective estrogen receptor modulator (SERM). A previous study demonstrated that SERM exhibits anti-inflammatory effects on colitis by promoting the anti-inflammatory phenotype of monocytes in murine colitis. However, the therapeutic effects of oxindole on colitis remain unknown. Therefore, we evaluated the efficacy of IA-0130 on dextran sulfate sodium (DSS)-induced mouse colitis.

METHODS

The DSS-induced colitis mouse model was established by administration of 2.5% DSS for 5 days. Mice were orally administered with IA-0130 (0.01 mg/kg or 0.1 mg/kg) or cyclosporin A (CsA; 30 mg/kg). Body weight, disease activity index score and colon length of mice were calculated and histological features of mouse colonic tissues were analyzed using hematoxylin and eosin staining. The expression of inflammatory cytokines and tight junction (TJ) proteins were analyzed using quantitative real-time PCR and enzyme-linked immunosorbent assay. The expression of interleukin-6 (IL-6) signaling molecules in colonic tissues were investigated using Western blotting and immunohistochemistry (IHC).

RESULTS

IA-0130 (0.1 mg/kg) and CsA (30 mg/kg) prevented colitis symptom, including weight loss, bleeding, colon shortening, and expression of pro-inflammatory cytokines in colon tissues. IA-0130 treatment regulated the mouse intestinal barrier permeability and inhibited abnormal TJ protein expression. IA-0130 down-regulated IL-6 expression and prevented the phosphorylation of signaling molecules in colonic tissues.

CONCLUSIONS

This study demonstrated that IA-0130 suppressed colitis progression by inhibiting the gp130 signaling pathway and expression of pro-inflammatory cytokines, and maintaining TJ integrity.

Lactobacillus rhamnosus GG and Tannic Acid Synergistically Promote the Gut Barrier Integrity in a Rat Model of Experimental Diarrhea via Selective Immunomodulatory Cytokine Targeting

SCOPE

Diarrhea is a common health issue that contributes to a significant annual death rate among children and the elderly worldwide. The anti-diarrheal activity of Lactobacillus rhamnosus GG (LGG) and tannic acid (TA), alone or combined, is examined, in addition to their effect on intestinal barrier integrity.

METHODS AND RESULTS

Fifty-six adult male Wistar rats are randomly assigned into seven groups: control, LGG alone, TA alone, diarrhea model, diarrhea+LGG, diarrhea+TA, and diarrhea+LGG+TA-treated groups. Diarrhea is induced by high-lactose diet (HLD) consumption. LGG (1x109 CFU/rat) and TA (100 mg Kg-1 d-1) were given orally 4 days after HLD feeding and continued for 10 days. Ileum specimens are processed for biochemical analysis of the local intestinal cytokines, polymerase chain reaction (PCR), and histological study. Also, immunohistochemistry-based identification of Proliferating Cell Nuclear Antigen (PCNA) and zonula occludens 1 (ZO-1) is performed. Compared to the diarrhea model group, both treatments maintain the intestinal mucosal structure and proliferative activity and preserve ZO-1 expression, with the combination group showing the maximal effect. However, LGG-treated diarrheic rats show a remarkable decrease in the intestinal tissue concentrations of tumor necrosis factor-alpha (TNF-α) and nuclear factor Kappa beta (NF-κB); meanwhile, TA treatment leads to a selective decrease of interferon-gamma (INF-γ) and transforming growth factor-beta (TGF-β1).

CONCLUSION

Individual LGG and TA treatments significantly alleviate diarrhea, probably through a selective immunomodulatory cytokine-dependent mechanism, while the combination of both synergistically maintains the intestinal mucosa by keeping the intestinal epithelial barrier function and regenerative capability.

Elucidating the modulatory role of dietary hydroxyproline on the integrity and functional performance of the intestinal barrier in early-weaned piglets: A comprehensive analysis of its interplay with the gut microbiota and metabolites

Piglets receive far less hydroxyproline (Hyp) from a diet after weaning than they obtained from sow's milk prior to weaning, suggesting that Hyp may play a protective role in preserving intestinal mucosal homeostasis. This study aimed to evaluate the effect of Hyp on intestinal barrier function and its associated gut microbiota and metabolites in early-weaned piglets. Eighty weaned piglets were divided into four groups and fed diets containing different Hyp levels (0 %, 0.5 %, 1 %, or 2 %) for 21 days. Samples, including intestinal contents, tissues, and blood, were collected on day 7 for analysis of microbial composition, intestinal barrier function, and metabolites. We demonstrated that dietary supplementation with 2 % Hyp improved the feed conversion ratio and reduced the incidence of diarrhea in early-weaned piglets compared to the control group. Concurrently, Hyp enhanced intestinal barrier function by facilitating tight junction protein (zonula occludens (ZO)-1 and occludin) expression and mucin production in the jejunal, ileal, and colonic mucosas. It also improved mucosal immunity (by increasing the amount of secretory IgA (sIgA) and the ratio of CD4+/CD8+ T lymphocytes and decreasing NF-κB phosphorylation) and increased antioxidant capacity (by raising total antioxidant capacity (T-AOC) and glutathione levels) in the intestinal mucosa. In addition, Hyp supplementation resulted in an increase in the levels of glycine, glutathione, and glycine-conjugated bile acids, while decreasing the concentrations of cortisol and methionine sulfoxide in plasma. Intriguingly, piglets fed diet containing Hyp exhibited a remarkable increase in the abundance of probiotic Enterococcus faecium within their colonic contents. This elevation occurred alongside an attenuation of pro-inflammatory responses and an enhancement in intestinal barrier integrity. Further, these changes were accompanied by a rise in anti-inflammatory metabolites, specifically glycochenodeoxycholic acid and guanosine, along with a suppression of pro-inflammatory lipid peroxidation products, including (12Z)-9,10-dihydroxyoctadec-12-enoic acid (9,10-DHOME) and 13-L-hydroperoxylinoleic acid (13(S)-HPODE). In summary, Hyp holds the capacity to enhance the intestinal barrier function in weaned piglets; this effect is correlated with changes in the gut microbiota and metabolites. Our findings provide novel insights into the role of Hyp in maintaining gut homeostasis, highlighting its potential as a dietary supplement for promoting intestinal health in early-weaned piglets.

Cadmium modulates intestinal Wnt/β-catenin signaling ensuing intestinal barrier disruption and systemic inflammation

The intricate architecture of the intestinal epithelium, crucial for nutrient absorption, is constantly threatened by environmental factors. The epithelium undergoes rapid turnover, which is essential for maintaining homeostasis, under the control of intestinal stem cells (ISCs). The central regulator, Wnt/β-catenin signaling plays a key role in intestinal integrity and turnover. Despite its significance, the impact of environmental factors on this pathway has been largely overlooked. This study, for the first time, investigates the influence of Cd on the intestinal Wnt signaling pathway using a mouse model. In this study, male BALB/c mice were administered an environmentally relevant Cd dose (0.98 mg/kg) through oral gavage to investigate the intestinal disruption and Wnt signaling pathway. Various studies, including histopathology, immunohistochemistry, RT-PCR, western blotting, ELISA, intestinal permeability assay, and flow cytometry, were conducted to study Cd-induced changes in the intestine. The canonical Wnt signaling pathway experienced significant downregulation as a result of sub-chronic Cd exposure, which caused extensive damage throughout the small intestine. Increased intestinal permeability and a skewed immune response were also observed. To confirm that Wnt signaling downregulation is the key driver of Cd-induced gastrointestinal toxicity, mice were co-exposed to LiCl (a recognized Wnt activator) and Cd. The results clearly showed that the harmful effects of Cd could be reversed, which is strong evidence that Cd mostly damages the intestine through the Wnt/β-catenin signalling axis. In conclusion, this research advances the current understanding of the role of Wnt/β catenin signaling in gastrointestinal toxicity caused by diverse environmental pollutants.

Dietary nutrition, intestinal microbiota dysbiosis and post-weaning diarrhea in piglets

Weaning is a critical transitional point in the life cycle of piglets. Early weaning can lead to post-weaning syndrome, destroy the intestinal barrier function and microbiota homeostasis, cause diarrhea and threaten the health of piglets. The nutritional components of milk and solid foods consumed by newborn animals can affect the diversity and structure of their intestinal microbiota, and regulate post-weaning diarrhea in piglets. Therefore, this paper reviews the effects and mechanisms of different nutrients, including protein, dietary fiber, dietary fatty acids and dietary electrolyte balance, on diarrhea and health of piglets by regulating intestinal function. Protein is an essential nutrient for the growth of piglets; however, excessive intake will cause many harmful effects, such as allergic reactions, intestinal barrier dysfunction and pathogenic growth, eventually aggravating piglet diarrhea. Dietary fiber is a nutrient that alleviates post-weaning diarrhea in piglets, which is related to its promotion of intestinal epithelial integrity, microbial homeostasis and the production of short-chain fatty acids. In addition, dietary fatty acids and dietary electrolyte balance can also facilitate the growth, function and health of piglets by regulating intestinal epithelial function, immune system and microbiota. Thus, a targeted control of dietary components to promote the establishment of a healthy bacterial community is a significant method for preventing nutritional diarrhea in weaned piglets.

Exploring the therapeutic potential of cinnamoyl derivatives in attenuating inflammation in lipopolysaccharide-induced Caco-2 cells

Aim: In gastrointestinal (GI) diseases, lipopolysaccharide (LPS) exacerbates gut-barrier dysfunction and inflammation. Cinnamoyl derivatives show potential in mitigating LPS-induced inflammation.Materials & methods: We assessed intestinal epithelial barrier function using Trans-epithelial electrical resistance values and measured inflammatory mediators through real-time PCR and ELISA in Caco-2 cells.Results: LPS treatment increased IL-6, IL-1β, TNF-α, PGE2 and TRL4 expression in Caco-2 cells. Pre-treatment with DM1 (1 or 10 μM) effectively countered LPS-induced TLR4 overexpression and reduced IL-6, IL-1β, TNF-α and PGE2 levels.Conclusion: DM1 holds promise in regulating inflammation and maintaining intestinal integrity by suppressing TLR4 and inflammatory mediators in Caco-2 cells. These findings suggest a potential therapeutic avenue for GI diseases.

L-Glutamine Substantially Improves 5-Fluorouracil-Induced Intestinal Mucositis by Modulating Gut Microbiota and Maintaining the Integrity of the Gut Barrier in Mice

SCOPE

This study investigates the potential of glutamine to mitigate intestinal mucositis and dysbiosis caused by the chemotherapeutic agent 5-fluorouracil (5-FU).

METHODS AND RESULTS

Over twelve days, Institute of Cancer Research (ICR) mice are given low (0.5 mg kg-1) or high (2 mg kg-1) doses of L-Glutamine daily, with 5-FU (50 mg kg-1) administered between days six and nine. Mice receiving only 5-FU exhibited weight loss, diarrhea, abnormal cell growth, and colonic inflammation, correlated with decreased mucin proteins, increased endotoxins, reduced fecal short-chain fatty acids, and altered gut microbiota. Glutamine supplementation counteracted these effects by inhibiting the Toll-like receptor 4/nuclear factor kappa B (TLR4/NF-κB) pathway, modulating nuclear factor erythroid 2-related factor 2/heme oxygenase 1 (Nrf2/HO-1) oxidative stress proteins, and increasing mammalian target of rapamycin (mTOR) levels, thereby enhancing microbial diversity and protecting intestinal mucosa.

CONCLUSIONS

These findings underscore glutamine's potential in preventing 5-FU-induced mucositis by modulating gut microbiota and inflammation pathways.

hUC-MSCs therapy for Crohn's disease: efficacy in TNBS-induced colitis in rats and pilot clinical study

BACKGROUND

The use of mesenchymal stem cells (MSCs) has recently emerged as a promising new therapeutic strategy for many diseases including perianal fistulizing Crohn's disease (CD). Whether hUC-MSCs can promote the healing of luminal ulcer in CD has not been studied so far.

METHODS

The model of TNBS-induced colitis in rats was used to confirm the efficacy of hUC-MSCs in the treatment of CD. Then, seventeen CD patients refractory to or unsuitable for currently available therapies were enrolled and received once submucosal local injection through colonoscopy combined with once intravenous drip on the next day. All patients received a 24-week follow-up. Clinical and laboratory assessments were monitored at baseline, week 4, 8, 12, and 24. Endoscopic evaluations were conducted at baseline and week 12. Mucosal specimens were obtained at the margin of lesions by endoscopy biopsies and used for RNA sequencing. Two hUC-MSCs co-culture systems were established in vitro, one with the mucosa specimens and the other with M1 macrophages induced from THP1. The expressions of genes representing inflammation (TNFα, IL-6, and IL-1β) and intestinal barrier function (ZO1, CLAUDIN1, and CDH1) were tested by RT-PCR.

FINDINGS

hUC-MSCs treatment increased body weight and decreased disease activity index (DAI), colon macroscopic damage index (CMDI), and histopathological score (HPS) of rats with TNBS-induced colitis. The results of the clinical study also showed that this mode of hUC-MSCs application was associated with regression of intestinal ulceration. Eight patients (47%) got endoscopic responses (SES-CD improvement of ≥50% from baseline) and three patients (17.65%) got mucosal healing (SES-CD is zero), with a parallel improvement of clinical and laboratory parameters without serious adverse events. RNA sequencing showed hUC-MSCs therapy was associated with an upregulation of transcripts linked to intestinal epithelial barrier integrity and a downregulation of inflammatory signaling pathways in the intestinal mucosa, especially the TNF signaling pathway, IL-17 signaling pathway, and TLR signaling pathway. RNA expression of intestinal epithelial tight junction protein (ZO1, CLAUDIN1, and CDH1), and the RNA expression of major intestinal inflammatory factors in CD (IL-1β, IL-6, and TNFα, p < 0.001 for all) were improved significantly. Moreover, hUC-MSCs could attenuate the polarization of M1 macrophage induced from THP1, thereby decreasing the mRNA expression of IL-1β, IL-6, and TNFα significantly (p < 0.05 for all). TSG-6 expression was evaluated in hUC-MSCs culture supernatant after treatment with TNFα, IFNγ, and LPS for 48 h. And hUC-MSCs could inhibit the phosphorylation of JAK/STAT1 in the intestinal mucosa of CD patients.

INTERPRETATION

hUC-MSCs transplantation alleviated TNBS-induced colitis in rats. In this pilot clinical study, preliminary data suggested that this approach to administering hUC-MSCs might have potential for clinical efficacy and manageable safety in treating refractory CD, potentially providing hope for better outcomes. No serious adverse events were observed.

FUNDING

This work was funded by General Program of National Natural Science Foundation of China (Grant No. 82270639), the Scientific research project of Shanghai Municipal Health Committee (Grant No. 202240001), Specialty Feature Construction Project of Shanghai Pudong New Area Health Commission (Grant No. PWZzb2022-05), Shanghai East Hospital Youth Research and Cultivation Foundation program (Grant No. DFPY2022015), Peak Disciplines (Type IV) of Institutions of Higher Learning in Shanghai and Technology Development Project of Pudong Science, Technology and Economic Commission of Shanghai (Grant No. PKJ2021-Y08).

Effect of Salvia sclarea L. extract on growth performance, antioxidant capacity, and immune function in lambs

The aim of this experiment is to explore the effects of salvia sclarea extract on the growth performance, apparent nutrient digestibility, antioxidant capacity, and immune function of lambs. Sixty female lambs (Chinese Merino sheep) aged 2 months and weighing 20 ± 2 kg were selected and randomly divided into five groups of twelve lambs in each. While the control group (CK) received only basal feed, the experimental group was supplemented with different concentrations of salvia sclarea extract in the basal feed at 0.04 mL/kg (group CL1), 0.08 mL/kg (group CL2), 0.12 mL/kg (group CL3), and 0.16 mL/kg (group CL4). The feeding period was 85 days, including 15 days of pre-feeding and 70 days of regular feeding. Body weight and feed intake were recorded during the test period, and blood was collected at the end of the test for the determination of immune and antioxidant indices. The results showed that the average daily gain and average daily feed intake of lambs were significantly increased in CL3 group compared to CK group (p < 0.05). Also, the apparent nutrient digestibility of crude protein and neutral detergent fiber was significantly increased (p < 0.05). The Dry matter, acid detergent fiber and Ether extract were not significantly different (p > 0.05). The serum levels of superoxide dismutase, catalase, glutathione peroxidase, and antioxidant capacity were significantly higher in the CL2, CL3, and CL4 groups compared to CK group, while malondialdehyde levels were significantly lower (p < 0.05). The serum levels of immune globulin A, immune globulin G, immune globulin M, interferon-γ, and interleukin-10 were significantly higher and the levels of tumor necrosis factor-α and interleukin-1β were significantly lower in the CL2, CL3, and CL4 groups (p < 0.05). In conclusion, the addition of salvia sclarea extract to the ration promotes growth performance and nutrient digestion in lambs. Improvement of immune response by increasing immunoglobulin and cytokine concentrations. And it enhances the antioxidant status by increasing the antioxidant enzyme activity in lambs.

Introduction

This study aimed to explore the effects of Salvia sclarea extract on the growth performance, apparent nutrient digestibility, antioxidant capacity, and immune function of the lambs.

Methods

Sixty female lambs (Chinese Merino sheep) aged 2 months and weighing 20 ± 2 kg were selected and randomly divided into five groups of 12 lambs each. The control group (CK) received only basal feed, whereas the experimental group was supplemented with different concentrations of salvia sclarea extract in the basal feed at 0.04, 0.08, 0.12, and 0.16 mL/kg (CL1, CL2, CL3, and CL4, respectively). The feeding period was 85 days, including 15 days of pre-feeding and 70 days of regular feeding. Body weight and feed intake were recorded during the test period, and blood was collected at the end of the test to determine immune and antioxidant indices.

Results

The results showed that the average daily weight gain and feed intake of the lambs were significantly higher in the CL3 group than in the CK group (p < 0.05). In addition, the apparent nutrient digestibility of crude protein and neutral detergent fiber increased significantly (p < 0.05). The dry matter, acid detergent fiber, and ether extract were not significantly different (p > 0.05). Serum levels of superoxide dismutase, catalase, and glutathione peroxidase and antioxidant capacity were significantly higher in the CL2, CL3, and CL4 groups than in the CK group, whereas malondialdehyde levels were significantly lower (p < 0.05). The serum levels of immune globulin immune globulin A, immune globulin G, immune globulin M, interferon-γ, and interleukin-10 were significantly higher and the levels of tumor necrosis factor-α and interleukin-1β were significantly lower in the CL2, CL3, and CL4 groups (p < 0.05).

Discussion

In conclusion, the addition of the S. sclarea extract to the diet promoted growth performance and nutrient digestion in lambs. Immune response was improved by increasing Ig and cytokine concentrations. It enhances antioxidant status by increasing antioxidant enzyme activity in lambs.

Clostridium butyricum isolated from giant panda can attenuate dextran sodium sulfate-induced colitis in mice

Objective

Probiotics are beneficial to the intestinal barrier, but few studies have investigated probiotics from giant pandas. This study aims to explore the preventive effects of giant panda-derived Clostridium butyricum on dextran sodium sulfate (DSS)-induced colitis in mice.

Methods

Clostridium butyricum was administered to mice 14 days before administering DSS treatment to induce enteritis.

Results

Clostridium butyricum B14 could more effectively prevent colitis in mice than C. butyricum B13. C. butyricum B14 protected the mouse colon by decreasing the histology index and serum interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α) levels, which improved intestinal inflammation-related symptoms. In addition, the treatment led to the regulation of the expression of Tifa, Igkv12-89, and Nr1d1, which in turn inhibited immune pathways. The expression of Muc4, Lama3, Cldn4, Cldn3, Ocln, Zo1, Zo2, and Snai is related the intestinal mucosal barrier. 16S sequencing shows that the C. butyricum B14 significantly increased the abundance of certain intestinal probiotics. Overall, C. butyricum B14 exerted a preventive effect on colitis in mice by inhibiting immune responses, enhancing the intestinal barrier and increasing the abundance of probiotic species. Thus, C. butyricum B14 administration helps regulate the balance of the intestinal microecology. It can suppress immune pathways and enhance barrier-protective proteins.

Agaro-oligosaccharides mitigate deoxynivalenol-induced intestinal inflammation by regulating gut microbiota and enhancing intestinal barrier function in mice

Agarose-derived agaro-oligosaccharides (AgaroS) have been extensively studied in terms of structures and bioactivities; they reportedly possess antioxidant and anti-inflammatory activities that maintain intestinal homeostasis and host health. However, the protective effects of AgaroS on deoxynivalenol (DON)-induced intestinal dysfunction remain unclear. We investigated the effects of AgaroS on DON-induced intestinal dysfunction in mice and explored the underlying protective mechanisms. In total, 32 mice were randomly allocated to four treatments (n = 8 each) for 28 days. From day 1 to day 21, the control (CON) and DON groups received oral phosphate-buffered saline (200 μL per day); the AgaroS and AgaroS + DON groups received 200 mg AgaroS per kg body weight once daily by orogastric gavage. Experimental intestinal injury was induced by adding DON (4.8 mg per kg body weight) via gavage from day 21 to day 28. Phosphate-buffered saline was administered once daily by gavage in the CON and AgaroS groups. Herein, AgaroS supplementation led to a higher final body weight and smaller body weight loss and a lower concentration of plasma inflammatory cytokines, compared with the DON group. The DON group showed a significantly reduced ileal villus height and villus height/crypt depth, compared with the CON and AgaroS + DON groups. However, AgaroS supplementation improved DON-induced intestinal injury in mice. Compared with the DON group, ileal and colonic protein expression levels of claudin, occludin, Ki67, and mucin2 were significantly higher in the AgaroS supplementation group. Colonic levels of the anti-inflammatory cytokine IL-1β tended to be higher in the DON group than in the AgaroS + DON group. AgaroS altered the gut microbiota composition, accompanied by increased production of short-chain fatty acids in mice. In conclusion, our findings highlight a promising anti-mycotoxin approach whereby AgaroS alleviate DON-induced intestinal inflammation by modulating intestinal barrier functional integrity and gut microbiota in mice.

Maternal supplementation with konjac glucomannan improves maternal microbiota for healthier offspring during lactation

BACKGROUND

The maternal diet during gestation and lactation affects the health of the offspring. Konjac glucomannan (KGM) is a significantly functional polysaccharide in food research, possessing both antioxidant and prebiotic properties. However, the mechanisms of how KGM regulates maternal nutrition remain insufficient and limited. This study aimed to investigate maternal supplementation with KGM during late gestation and lactation to benefit both maternal and offspring generations.

RESULTS

Our findings indicate that KGM improves serum low density lipoprotein cholesterol (LDL-C) and antioxidant capacity. Furthermore, the KGM group displayed a significant increase in the feed intake-related hormones neuropeptide tyrosine (NPY), Ghrelin, and adenosine monophosphate-activated kinase (AMPK) levels. KGM modified the relative abundance of Clostridium, Candidatus Saccharimonas, unclassified Firmicutes, and unclassified Christensenellaceae in sow feces. Acetate, valerate, and isobutyrate were also improved in the feces of sows in the KGM group. These are potential target bacterial genera that may modulate the host's health. Furthermore, Spearman's correlation analysis unveiled significant correlations between the altered bacteria genus and feed intake-related hormones. More importantly, KGM reduced interleukin-6 (IL-6) levels in milk, further improved IL-10 levels, and reduced zonulin levels in the serum of offspring.

CONCLUSION

In conclusion, maternal dietary supplementation with KGM during late gestation and lactation improves maternal nutritional status by modifying maternal microbial and increasing lactation feed intake, which benefits the anti-inflammatory capacity of the offspring serum. © 2024 Society of Chemical Industry.

Trends in 3D models of inflammatory bowel disease

Inflammatory bowel disease (IBD) encompasses a set of chronic inflammatory conditions, namely Crohn's disease and ulcerative colitis. Despite all advances in the management of IBD, a definitive cure is not available, largely due to a lack of a holistic understanding of its etiology and pathophysiology. Several in vitro, in vivo, and ex vivo models have been developed over the past few decades in order to abbreviate remaining gaps. The establishment of reliable and predictable in vitro intestinal inflammation models may indeed provide valuable tools to expedite and validate the development of therapies for IBD. Three-dimensional (3D) models provide a more accurate representation of the different layers of the intestine, contributing to a stronger impact on drug screening and research on intestinal inflammation, and bridging the gap between in vitro and in vivo research. This work provides a critical overview on the state-of-the-art on existing 3D models of intestinal inflammation and discusses the remaining challenges, providing insights on possible pathways towards achieving IBD mimetic models. We also address some of the main challenges faced by implementing cell culture models in IBD research while bearing in mind clinical translational aspects.

The exposure in ovo to glyphosate on the integrity of intestinal epithelial tight junctions of chicks

Glyphosate is an ingredient widely used in various commercial formulations, including Roundup®. This study focused on tight junctions and the expression of inflammatory genes in the small intestine of chicks. On the sixth day of embryonic development, the eggs were randomly assigned to three groups: the control group (CON, n = 60), the glyphosate group (GLYP, n = 60), which received 10 mg of active glyphosate/kg egg mass, and the Roundup®-based glyphosate group also received 10 mg of glyphosate. The results indicated that the chicks exposed to glyphosate or Roundup® exhibited signs of oxidative stress. Additionally, histopathological alterations in the small intestine tissues included villi fusion, complete fusion of some intestinal villi, a reduced number of goblet cells, and necrosis of some submucosal epithelial cells in chicks. Genes related to the small intestine (ZO-1, ZO-2, Claudin-1, Claudin-3, JAM2, and Occludin), as well as the levels of pro-inflammatory cytokines (IFNγ, IL-1β, and IL-6), exhibited significant changes in the groups exposed to glyphosate or Roundup® compared to the control group. In conclusion, the toxicity of pure glyphosate or Roundup® likely disrupts the small intestine of chicks by modulating the expression of genes associated with tight junctions in the small intestine.

Bergenin Alleviates Ulcerative Colitis By Decreasing Gut Commensal Bacteroides vulgatus-Mediated Elevated Branched-Chain Amino Acids

Ulcerative colitis is closely associated with the dysregulation of gut microbiota. There is growing evidence that natural products may improve ulcerative colitis by regulating the gut microbiota. In this research, we demonstrated that bergenin, a naturally occurring isocoumarin, significantly ameliorates colitis symptoms in dextran sulfate sodium (DSS)-induced mice. Transcriptomic analysis and Caco-2 cell assays revealed that bergenin could ameliorate ulcerative colitis by inhibiting TLR4 and regulating NF-κB and mTOR phosphorylation. 16S rRNA sequencing and metabolomics analyses revealed that bergenin could improve gut microbiota dysbiosis by decreasing branched-chain amino acid (BCAA) levels. BCAA intervention mediated the mTOR/p70S6K signaling pathway to exacerbate the symptoms of ulcerative colitis in mice. Notably, bergenin greatly decreased the symbiotic bacteria Bacteroides vulgatus (B. vulgatus), and the gavage of B. vulgatus increased BCAA concentrations and aggravated the symptoms of ulcerative colitis in mice. Our findings suggest that gut microbiota-mediated BCAA metabolism plays a vital role in the protective effect of bergenin on ulcerative colitis, providing novel insights for ulcerative colitis prevention through manipulation of the gut microbiota.

Effects of Dietary Aflatoxin B1 on Hybrid Grouper (Epinephelus fuscoguttatus ♀ × Epinephelus lanceolatus ♂) Growth, Intestinal Health, and Muscle Quality

This study investigated the effects of varying doses of dietary aflatoxin B1 (AFB1) on the growth, intestinal health, and muscle quality of hybrid grouper. Four diets with varying AFB1 concentrations (0, 30, 445, and 2,230 μg kg-1) were used. Elevating AFB1 concentrations led to a decline in growth indexes, specifically the weight gain rate and the specific growth rate, although the survival rate remained unchanged. Morphological indicators showed a dose-dependent decline with AFB1 exposure. Intestinal MDA content and hindgut reactive oxygen species (ROS) levels increased, while antioxidant indexes and digestive enzymes decreased with higher AFB1 levels. AFB1 negatively influenced hindgut tight junction protein and antioxidant-related gene expression while promoting inflammation-related gene expression. The presence of AFB1 in the experiment led to a decrease in beneficial intestinal bacteria, such as Prevotella, and an increase in harmful intestinal bacteria, such as Prevotellaceae_NK3B31_group. Muscle lipid and unsaturated fatty acid content significantly decreased, while muscle protein and liver AFB1 content increased dramatically with higher AFB1 concentrations. AFB1 caused myofibrillar cleavage and myofilament damage, leading to increased spaces between muscle fibers. In conclusion, diets with AFB1 levels exceeding 30 μg kg-1 inhibited hybrid grouper growth, while levels surpassing 445 μg kg-1 resulted in hindgut ROS accumulation, inflammation, elevated intestinal permeability, reduced digestive enzyme activity, and compromised muscle quality.

Fermentation enhances the amelioration effect of bee pollen on Caco-2 monolayer epithelial barrier dysfunction based on NF-κB-mediated MLCK-MLC signaling pathway

Intestinal barrier integrity is essential for normal nutrient digestion and absorption and disease resistance. This study aims to investigate how fermentation affects the ameliorative effect of bee pollen on the intestinal barrier dysfunction stimulated by interferon-γ and tumor necrosis factor (IFN-γ/TNF-α) cytokines. The results indicated that fermentation enhances the alleviating effect of bee pollen on intestinal barrier dysfunction (including elevated trans epithelial electrical resistance and decreased paracellular permeability). In addition, fermented bee pollen (FBP) significantly decreased (p < 0.05) the secretion levels of interleukin (IL)-6, IL-8, and IL-1β and expression of cyclooxygenase (COX)-2 protein in intestinal barrier cells. Furthermore, fermentation improved the ability of bee pollen to up-regulate the expression of tight junction proteins including zonula occludens (ZO)-1, occluding, and claudin-1. Notably, FBP showed stronger ability to inhibit the expression of nuclear factor kappa-B (NF-κB) mediated myosin light chain kinase (MLCK) and myosin light chain (MLC) signaling pathway associated with phosphorylated proteins. Overall, our results indicated that fermentation enhances the protective effect of bee pollen on the intestinal barrier, and FBP has promising potential to be used as a novel functional food to protect the intestinal barrier.

Zinc glycine chelate ameliorates DSS-induced intestinal barrier dysfunction via attenuating TLR4/NF-κB pathway in meat ducks

BACKGROUND

Zinc glycine chelate (Zn-Gly) has anti-inflammation and growth-promoting properties; however, the mechanism of Zn-Gly contribution to gut barrier function in Cherry Valley ducks during intestinal inflammation is unknown. Three-hundred 1-day-old ducks were divided into 5 groups (6 replicates and 10 ducks per replicate) in a completely randomized design: the control and dextran sulfate sodium (DSS) groups were fed a corn-soybean meal basal diet, and experimental groups received supplements of 70, 120 or 170 mg/kg Zn in form of Zn-Gly. The DSS and treatment groups were given 2 mL of 0.45 g/mL DSS daily during d 15-21, and the control group received normal saline. The experiment lasted 21 d.

RESULTS

Compared with DSS group, 70, 120 and 170 mg/kg Zn significantly increased body weight (BW), villus height and the ratio of villus to crypt, and significantly decreased the crypt depth of jejunum at 21 d. The number of goblet cells in jejunal villi in the Zn-Gly group was significantly increased by periodic acid-Schiff staining. Compared with control, the content of intestinal permeability marker D-lactic acid (D-LA) and fluxes of fluorescein isothiocyanate (FITC-D) in plasma of DSS group significantly increased, and 170 mg/kg Zn supplementation significantly decreased the D-LA content and FITC-D fluxes. Compared with control, contents of plasma, jejunum endotoxin and jejunum pro-inflammatory factors IL-1β, IL-6 and TNF-α were significantly increased in DSS group, and were significantly decreased by 170 mg/kg Zn supplementation. Dietary Zn significantly increased the contents of anti-inflammatory factors IL-10, IL-22 and sIgA and IgG in jejunum. Real-time PCR and Western blot results showed that 170 mg/kg Zn supplementation significantly increased mRNA expression levels of CLDN-1 and expression of OCLN protein in jejunum, and decreased gene and protein expression of CLDN-2 compared with DSS group. The 120 mg/kg Zn significantly promoted the expressions of IL-22 and IgA. Dietary Zn-Gly supplementation significantly decreased pro-inflammatory genes IL-8 and TNF-α expression levels and TNF-α protein expression in jejunum. Additionally, Zn significantly reduced the gene and protein expression of TLR4, MYD88 and NF-κB p65.

CONCLUSIONS

Zn-Gly improved duck BW and alleviated intestinal injury by regulating intestinal morphology, barrier function and gut inflammation-related signal pathways TLR4/MYD88/NF-κB p65.

Gut toxicity of polystyrene microplastics and polychlorinated biphenyls to Eisenia fetida: Single and co-exposure effects with a focus on links between gut bacteria and bacterial translocation stemming from gut barrier damage

Microplastics' (MPs) ability to sorb and transport polychlorinated biphenyls (PCBs) in soil ecosystems warrants significant attention. Although organisms mainly encounter pollutants through the gut, the combined pollution impact of MPs and PCBs on soil fauna gut toxicity remains incompletely understood. Consequently, this study examined the gut toxicity of polystyrene MPs (PS-MPs) and PCB126 on Eisenia fetida, emphasizing the links between gut bacteria and bacterial translocation instigated by gut barrier impairment. Our findings underscored that E. fetida could ingest PS-MPs, which mitigated the PCB126 accumulation in E. fetida by 9.43 %. Exposure to PCB126 inhibited the expression of gut tight junction (TJ) protein genes. Although the presence of PS-MPs attenuated this suppression, it didn't alleviate gut barrier damage and bacterial translocation in the co-exposure group. This group demonstrated a significantly increased level of gut bacterial load (BLT, ANOVA, p = 0.005 vs control group) and lipopolysaccharide-binding protein (LBP, ANOVA, all p < 0.001 vs control, PCB, and PS groups), both of which displayed significant positive correlations with antibacterial defense. Furthermore, exposure to PS-MPs and PCB126, particularly within the co-exposure group, results in a marked decline in the dispersal ability of gut bacteria. This leads to dysbiosis (Adonis, R2 = 0.294, p = 0.001), with remarkable signature taxa such as Janthinobacterium, Microbacterium and Pseudomonas, being implicated in gut barrier dysfunction. This research illuminates the mechanism of gut toxicity induced by PS-MPs and PCB126 combined pollution in earthworms, providing novel insights for the ecological risk assessment of soil.

Microalgae polysaccharides exert antioxidant and anti-inflammatory protective effects on human intestinal epithelial cells in vitro and dextran sodium sulfate-induced mouse colitis in vivo

Microalgae polysaccharides (MAPS) have emerged as novel prebiotics, but their direct effects on intestinal epithelial barrier are largely unknown. Here, MAPS isolated from Chlorella pyrenoidosa, Spirulina platensis, and Synechococcus sp. PCC 7002 were characterized as mainly branched heteropolysaccharides, and were bioavailable to Caco-2 cells based on fluorescein isothiocyanate labeling and flow cytometry analysis. These MAPS were equally effective to scavenge hydroxyl and superoxide radicals in vitro and to attenuate the H2O2-, dextran sodium sulfate-, tumor necrosis factor α-, and interleukin 1β-induced burst of intracellular reactive oxygen species and mitochondrial superoxide radicals, interleukin-8 production, cyclooxygenase-2 and inducible nitric oxide synthase expression, and/or tight junction disruption in polarized Caco-2 cells. MAPS and a positive drug Mesalazine were intragastrically administered to C57BL/6 mice daily for 7 d during and after 4-d dextran sodium sulfate exposure. Clinical signs and colon histopathology revealed equivalent anti-colitis efficacies of MAPS and Mesalazine, and based on biochemical analysis of colonic tight junction proteins, goblet cells, mucin 2 and trefoil factor 3 transcription, and colonic and peripheral pro-inflammatory cytokines, MAPS alleviated dextran sodium sulfate-induced intestinal epithelial barrier dysfunction, and their activities were even superior than Mesalazine. Overall, MAPS confer direct antioxidant and anti-inflammatory protection to intestinal epithelial barrier function.

Protective effects of metformin in the pro-inflammatory cytokine induced intestinal organoids injury model

Pathogenesis of inflammatory bowel disease (IBD) accompanies disrupted intestinal tight junctions. However, many approaches of therapeutics for IBD are focused only on anti-inflammatory effects and most cellular experiments are based on two-dimensional cell lines which have insufficient circumstances of intestine. Thus, here, we used three-dimensional structure intestinal organoids to investigate effects of metformin in the in vitro IBD condition. In this study, we focused on both tight junctions and the levels of inflammatory cytokines. Metformin enhances the intestinal barrier in injured intestine via upregulation of AMP-activated protein kinase, dysfunction of which contributes to the pathogenesis of intestinal diseases. We aim to investigate the effects of metformin on cytokine-induced injured intestinal organoids. Tumor necrosis factor-alpha (TNF-α) was used to induce intestinal injury in an organoid model, and the effects of metformin were assessed. Cell viability and levels of inflammatory cytokines were quantified in addition to tight junction markers. Furthermore, 4 kDa FITC-dextran was used to assess intestinal permeability. The upregulation of inflammatory cytokine levels was alleviated by metformin, which also restored the intestinal epithelium permeability in TNF-α-treated injury organoids. We confirmed that claudin-2 and claudin-7, representative tight junction markers, were also protected by metformin treatment. This study confirms the protective effects of metformin, which could be used as a therapeutic strategy for inflammatory intestinal diseases.

Allergic Airway Inflammation Emerges from Gut Inflammation and Leakage in Mouse Model of Asthma

Asthma is an allergic airway inflammatory disease characterized by type 2 immune responses. Growing evidence suggests an association between allergic airways and intestinal diseases. However, the primary site of disease origin and initial mechanisms involved in the development of allergic airway inflammation (AAI) is not yet understood. Therefore, the initial contributing organs and mechanisms involved in the development of AAI are investigated using a mouse model of asthma. This study, without a local allergen challenge into the lungs, demonstrates a significant increase in intestinal inflammation with signature type-2 mediators including IL-4, IL-13, STAT6, eosinophils, and Th2 cells. In addition, gut leakage and mRNA expressions of gut leakage markers significantly increase in the intestine. Moreover, reduced mRNA expressions of tight junction proteins are observed in gut and interestingly, in lung tissues. Furthermore, in lung tissues, an increased pulmonary barrier permeability and IL-4 and IL-13 levels associated with significant increase of lipopolysaccharide-binding protein (LBP-gut leakage marker) and eosinophils are observed. However, with local allergen challenges into the lungs, these mechanisms are further enhanced in both gut and lungs. In conclusion, the primary gut originated inflammatory responses translocates into the lungs to orchestrate AAI in a mouse model of asthma.

Lactiplantibacillus plantarum HY7718 Improves Intestinal Integrity in a DSS-Induced Ulcerative Colitis Mouse Model by Suppressing Inflammation through Modulation of the Gut Microbiota

Inflammatory bowel disease (IBD), a chronic condition that causes persistent inflammation in the digestive system, is closely associated with the intestinal microbiome. Here, we evaluated the effects of Lactiplantibacillus plantarum HY7718 (HY7718) on IBD symptoms in mice with dextran sulfate sodium (DSS)-induced colitis. Oral administration of HY7718 led to significant improvement in the disease activity index score and the histological index, as well as preventing weight loss, in model mice. HY7718 upregulated the expression of intestinal tight junction (TJ)-related genes and downregulated the expression of genes encoding pro-inflammatory cytokines and genes involved in the TLR/MyD88/NF-κB signaling pathway. Additionally, HY7718 reduced the blood levels of pro-inflammatory cytokines, as well as reversing DSS-induced changes to the composition of the intestinal microbiome. HY7718 also increased the percentage of beneficial bacteria (Lactiplantibacillus and Bifidobacterium), which correlated positively with the expression of intestinal TJ-related genes. Finally, HY7718 decreased the population of pathogens such as Escherichia, which correlated with IBD symptoms. The data suggest that HY7718 improves intestinal integrity in colitis model mice by regulating the expression of TJ proteins and inflammatory cytokines, as well as the composition of the intestinal microflora. Thus, L. plantarum HY7718 may be suitable as a functional supplement that improves IBD symptoms and gut health.

Feeding Strategies with Multi-Strain Probiotics Affect Growth, Health Condition, and Disease Resistance in Asian Seabass (Lates calcarifer)

A 16-week feeding trial was done to examine the impacts of continuous feeding (CF) or pulse-feeding (PF) of multi-strain probiotics on Asian seabass (Lates calcarifer, 30.0 ± 0.1 g) juveniles. In this study, three different multi-strain probiotic mixtures were added to a basal diet, including (I) a mixture of different strains of Lactobacillus plantarum, (II) a mixture of the first probiotic (I) + L. delbrueckii sub bulgaricus, L. rhamnosus and L. acidophilus, and (III) a mixture of the second probiotic (II) + two quorum quenching (QQ) bacteria (Bacillus thuringiensis QQ1 and B. cereus QQ2). CF (every day) or PF (every two weeks) strategies were applied for using the abovementioned probiotics to design seven experimental groups including C (control, without probiotics), CF-I (continuous feeding of fish with the probiotic mixture I), CF-II (continuous feeding of fish with the probiotic mixture II), CF-III (continuous feeding of fish with the probiotic mixture III), PF-I (pulse-feeding of fish with the probiotic mixture I), PF-II (pulse-feeding of fish with the probiotic mixture II), and PF-III (pulse-feeding of fish with the probiotic mixture III). Four hundred and twenty fish were stocked into 21 circular polyethylene tanks with 220 L volume (20 fish/tank). Each dietary treatment had three replicates. Tanks were supplied with seawater (temperature = 30.5 °C, salinity = 45 g L-1) in a flow-throw system. Fish in CF-I, CF-II, and CF-III had higher growth rate (ca. 113-145%) and better feed conversion ratio than fish fed C and PF-I (P < 0.05). Fish in the CF-III group had the highest protease activity. Continuous feeding strategy resulted in a higher amount of glutathione and catalase activities in both the liver and plasma as well as higher superoxide dismutase activity in the liver of fish. Pulse-feeding strategy resulted in lower plasma lactate dehydrogenase and aspartate aminotransferase levels than the CF strategy. Regardless of feeding strategy, different probiotic mixtures significantly enhanced blood hemoglobin and hematocrit levels compared to the control. Continuous feeding with the multi-strain probiotics resulted in a higher survival rate against Vibrio harveyi than the PF method. Continuous feeding induced higher mRNA transcription levels of granulocyte-macrophage colony-forming cells and interleukin 10 genes in the gut of fish than PF strategy. In conclusion, continuous feeding with multi-strain probiotics is better than pulse-feeding on growth, feed utilization, antioxidant capacity, and the gut's immune-related genes and led to higher resistance of L. calcarifer in challenge with V. harveyi.

A proteomic insight reveals the role of food-associated Lactiplantibacillus plantarum C9O4 in reverting intestinal inflammation

Nowadays, Western diets and lifestyle lead to an increasing occurrence of chronic gut inflammation that represents an emerging health concern with still a lack of successful therapies. Fermented foods, and their associated lactic acid bacteria, have recently regained popularity for their probiotic potential including the maintenance of gut homeostasis by modulating the immune and inflammatory response. Our study aims to investigate the crosstalk between the food-borne strain Lactiplantibacillus plantarum C9O4 and intestinal epithelial cells in an in vitro inflammation model. Cytokines profile shows the ability of C9O4 to significantly reduce levels of IL-2, IL-5, IL-6, and IFN-γ. Proteomic functional analysis reveals an immunoregulatory role of C9O4, able to revert the detrimental effects of IFN-γ through the JAK/STAT pathway in inflamed intestinal cells. These results suggest a promising therapeutic role of fermented food-associated microbes for the management of gastrointestinal inflammatory diseases. Data are available via ProteomeXchange with identifier PXD042175.

Deciphering the interplay between LPS/TLR4 pathways, neurotransmitter, and deltamethrin-induced depressive-like behavior: Perspectives from the gut-brain axis

The improper use of deltamethrin (DM) can result in its accumulation in soil, water, food, and even the human body, which is associated with an elevated risk of neurotoxicity and behavioral abnormalities; however, the underlying mechanisms remain insufficiently investigated. Emerging evidence underscores the significance of the gut-brain axis in central nervous system (CNS) dysfunctions. Accordingly, this study investigates the role of the gut-brain axis in DM-induced behavioral anomalies in mice. The results showed that DM exposure induced depressive-like behavior, and the hippocampus, the region that is responsible for the modulation of emotional behavior, showed structural integrity disrupted (neuronal nuclear shrinkage and decreased tight junction protein expression). In addition, DM exposure led to compromised gut barrier integrity (disruptions on crypt surfaces and decreased tight junction protein expression), which might contribute to the gut bacterial-derived lipopolysaccharide (LPS) leakage into the bloodstream and reaching the brain, triggering LPS/toll-like receptor (TLR) 4 -mediated increases in brain pro-inflammatory cytokines. Subsequently, we observed a disturbance in neurotransmitter metabolic pathways following DM exposure, which inhibited the production of 5-hydroxytryptamine (5-HT). Additionally, DM exposure resulted in gut microbiota dysbiosis. Characteristic bacteria, such as Alistipes, Bifidobacterium, Gram-negative bacterium cTPY-13, and Odoribacter exhibited significant correlations with behavior, tight junction proteins, inflammatory response, and neurotransmitters. Further fecal microbiota transplantation (FMT) experiments suggested that DM-induced gut microbiota dysbiosis might contribute to depressive-like behavior. These results provide a new perspective on the toxicity mechanism of DM, indicating that its neurotoxicity may be partially regulated by the microbiota-gut-brain axis.

Exploring the links between necrotizing enterocolitis and cow's milk protein allergy in preterm infants: a narrative review

A broad range of allergic disorders and intolerance are associated with cow's milk protein in the infant diet. Allergy and intolerance to cow's milk proteins are commonly recognized in the healthy term infant, and the prevalence cow's milk protein intolerance (CMPI) varies widely but 5 challenge confirmed studies free from selection bias ranged from 1.9%-4.9%. These disorders are classified by the presence of IgE, non-IgE or T-cell-mediated signaling. Additionally, the severity of these adverse food reactions can range from mild gastrointestinal symptoms to severe sepsis-like episodes, as in the case of food protein-induced enterocolitis syndrome (FPIES). Food protein-induced intolerance in the healthy young infant lies in stark contrast to enterocolitis that typically occurs in the preterm neonate. Necrotizing enterocolitis (NEC) is a distinct progressive disease process, usually characterized by a high mortality rate, with a risk of death from 30% to 50%. While its exact etiology is unclear, its main triggers include formula (cow's milk protein), hypoxia, perfusion-related issues, and unregulated inflammation in the premature intestine. The distinction between NEC and cow's milk protein intolerance is difficult to discern in some cases. In the late preterm population, infants with colitis can have both NEC and cow's milk intolerance on the differential. In infants with multiple episodes of mild NEC, cow's milk protein intolerance may be the underlying diagnosis. In this review, we compare the pathophysiological characteristics, diagnosis and treatment of disorders of cow's milk protein intolerance with the entity of preterm NEC. This review highlights similarities in both entities and may inspire future cross-disciplinary research.

Mesobiliverdin IXα-enriched microalgae feed additive eliminates reliance on antibiotic tylosin to promote intestinal health of weaning piglets

Weaning is a critical period in raising pigs. Novel animal feed additives that promote gut health and regulate immune function of piglets without antibiotics are needed. In this study, we aimed to test the ability of mesobiliverdin IXα-enriched microalgae (MBV IXα-enriched microalgae) to eliminate reliance on antibiotics to promote intestinal health in piglets. Eighty 28-day-old weaned piglets were randomly allocated to four groups each with four replicate pens and five piglets per pen. The dietary treatments were a basal diet as control (NC), basal diet plus 0.05% tylosin (PC), basal diet plus 0.1% or 0.5% MBV IXα-enriched microalgae as low (MBV-SP1) or high (MBV-SP2) dose respectively. All treated animals showed no significant differences in live weight, average daily gain and feed efficiency compared to control animals. Histological examination showed that MBV-SP1 and particularly MBV-SP2 increased the ratio of villus height to crypt depth in the jejunum and ileum compared to NC (p < 0.05). Similarly, tylosin treatment also increased villi lengths and the ratio of villus height to crypt depth in the jejunum and ileum compared to the NC (p < 0.05). MBV-SP1 and particularly MBV-SP2 reduced the levels of inflammatory cytokines interleukin-6 and tumour necrosis factor-alpha in the small intestine. MBV-SP2 and tylosin similarly reduced the lipid peroxidation marker (TBARS value) in the duodenum and ileum. In conclusion, feed supplementation with MBV IXα-enriched microalgae improved gut health by villus height and production of immunomodulators that correlated with down-regulated secretion of inflammatory cytokines.

Cinnamon (Cinnamomum cassia) hot water extract improves inflammation and tight junctions in the intestine in vitro and in vivo

The natural byproduct Cinnamomum cassia was widely used in ancient Asia to cure disease because of its various pharmacological effects. Despite its ethnomedicinal benefits, few studies on the intestinal anti-inflammatory effect of C. cassia have been reported. Therefore, this study aimed to evaluate the potential beneficial effects of C. cassia on the intestine in vitro and in vivo. Herein, the effects of cinnamon hot water extract (CWE) on tight junction (TJ) barrier function, transepithelial electrical resistance, and mRNA expression were confirmed in Caco-2 cells. The CWE treatment groups showed significantly enhanced cell permeability, proinflammatory cytokine mRNA expression, and TJ expression. CWE-treated mice showed an improved histological index and decreased cytokine concentrations compared with those of colitis model mice. These results suggest that CWE alleviated inflammatory damage and improved the TJ barrier, indicating that CWE may be used as a functional food to improve intestinal health.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10068-023-01292-3.

Effects of combined application of benzoic acid and 1-monolaurin on growth performance, nutrient digestibility, gut microbiome and inflammatory factor levels in weaned piglets

BACKGROUND

Our previous study observed that benzoic acid and 1-monolaurin have a synergistic bactericidal effect. Moreover, their improvement effect of benzoic acid and 1-monolaurin on the growth performance and diarrhea of weaned piglets was better than the two feedings alone. However, it is not clear how the combination of benzoic acid and 1-monolaurin affects the growth performance of weaned piglets. Therefore, 100 weaned piglets (mean weight 7.03 ± 1.04 kg, mean weaning age 26 d) were randomly divided into two groups: (1) basal diet control (CON); (2) basal diet supplemented with 0.6% benzoic acid and 0.1% 1-monolaurin (CA). The experiment lasted 28 days after weaning. The effects of benzoic acid and 1-monolaurin supplementation on growth performance, apparent nutrient digestibility, intestinal flora composition and function, and inflammatory factor levels of weaned piglets were investigated.

RESULTS

The feed conversion efficiency of piglets in the CA group between 15 and 28 d and 1 and 28 d after weaning was significantly higher than that in the CON group (P < 0.05). Additionally, the diarrhea proportion and frequency of piglets in the CA group 1-14 days post-weaning were significantly decreased (P < 0.05). The apparent digestibility of dry matter, organic matter and crude protein of piglets in the CA group was significantly higher than the CON group on days 14 and 28 (P < 0.05). The microbial composition in the cecal digesta of piglets was detected. The results indicated that the CA group piglets were significantly supplemented with g_YRC22 at day 14 and g_Treponema, g_Pseudomonas, and g_Lachnobacterium at day 28 (P < 0.05; log LDA > 2). No significant difference was observed between the CON and CA groups in the content of short-chain fatty acids. In addition, serum IL-1β level significantly decreased at day 28 in the CA group compared with the CON group, while serum endotoxin content was significantly reduced at day 14.

CONCLUSION

Therefore, dietary supplementation of 0.6% benzoic acid and 0.1% 1-monolaurin enhanced growth performance and nutrient digestibility, affected gut microflora composition, and decreased systemic inflammatory response and intestinal permeability of weaned piglets. These outcomes provide a theoretical basis for applying of benzoic acid and 1-monolaurin over weaned piglets.

Konjac glucomannan-assisted curcumin alleviated dextran sulfate sodium-induced mice colitis via regulating immune response and maintaining intestinal barrier integrity

Curcumin has been proven to be an effective strategy for reducing inflammatory responses. However, low bioavailability and instability at the physiological pH have limited its anti-inflammatory activity in ulcerative colitis patients. In the present study, a complex of curcumin and konjac glucomannan (KGM) effectively inhibited intestinal inflammation and this effect was associated with KGM degradation degrees. Results demonstrated that treatment with the complex markedly mitigated colitis symptoms and decreased inflammatory cytokines levels, especially in the complex treatment groups with K110 (KGM treated in 110 °C) and konjac oligosaccharides (KOSs). Furthermore, increasing the KOS content in KOC (the complex of curcumin and KOS) promoted the gene expressions of the intestinal barrier and inhibited the gene expressions of inflammatory cytokines, as well as improved gut microbiota dysregulation. Overall, our studies suggest that the complex of curcumin and KGM exerts effective anti-inflammatory effects by regulating the intestinal immune response and modulating microbiota diversity and composition.

The effects of sodium butyrate (NaB) combination with soy saponin dietary supplementation on the growth parameters, intestinal performance and immune-related genes expression of hybrid grouper (Epinephelus fuscoguttatus♀ × E. lanceolatus♂)

Soy saponins are generally known to have negative effects on growth and the intestines of aquatic animals, and appropriate levels of sodium butyrate (NaB) may provide some mitigating effects. We investigated the effects of low and high levels of soy saponin and the protective effects of NaB (based on high level of soy saponin) on growth, serum cytokines, distal intestinal histopathology, and inflammation in hybrid grouper (Epinephelus fuscoguttatus ♀ × E. lanceolatus ♂). The experiment included four groups: fishmeal group (FM, 0.00% saponin and 0.00% NaB), low saponin group (SL, 0.30% saponin and 0.00% NaB), high saponin group (SH, 1.50% saponin and 0.00% NaB) and high saponin with NaB group (SH-NaB, 1.50% saponin and 0.13% NaB). The results showed compared to FM, the final body weight (FBW) and weight gain (WG) were significantly higher and lower in SL and SH, respectively (P < 0.05). Compared to SH, the FBW and WG were significant higher in SH-NaB (P < 0.05). In the serum, compared to FM, the interferon γ (IFN-γ) and interleukin-1β (IL-1β) levels in SH were significantly increased (P < 0.05). Compared to SH, the IFN-γ level was significantly decreased in SH-NaB (P < 0.05). In the distal intestine, based on Alcian Blue-Periodic Acid-Schiff (AB-PAS) observation, the goblet cell/μm was significantly increased and decreased in the SL and SH, respectively, compared to FM. The intestinal diameter/plica height ratio in the SH was significantly higher than those in the FM, SL and SH-NaB (P < 0.05). The NO and ONOO- levels in the SH were significantly higher than that in FM and SL (P < 0.05). At the transcriptional level in the distal intestine, compared to FM, the mRNA levels of tumor necrosis factor (tnfα), il1β, interleukin-8 (il8) and ifnγ were significantly up-regulated in the SH (P < 0.05). Compared to the SH, tnfα, il8 and ifnγ were significantly down-regulated in the SH-NaB (P < 0.05). Compared to the FM, the mRNA levels of claudin3, claudin15, zo2 and zo3 were significantly up-regulated in the SL (P < 0.05). The mRNA levels of occludin, claudin3, claudin12, claudin15, zo1, zo2 and zo3 were significantly down-regulated in the SH compared to the FM (P < 0.05). Additionally, compared to the SH, the mRNA levels of occludin, claudin3, claudin12, claudin15, zo1, zo2 and zo3 were significantly up-regulated in the SH-NaB (P < 0.05). After the 7-day Vibrio parahaemolyticus challenge test, the survival was significantly higher and lower in the SL and SH, respectively, compared to FM (P < 0.05). Overall, low and high levels of soy saponins had positive and negative effects on growth, disease resistance, serum cytokines, and distal intestinal development and anti-inflammation, respectively, in hybrid grouper. NaB effectively increased disease resistance and improved distal intestinal inflammation in hybrid grouper, but the effects of NaB were mainly observed in improving distal intestinal tight junctions.

A blend of selected botanicals maintains intestinal epithelial integrity and reduces susceptibility to Escherichia coli F4 infection by modulating acute and chronic inflammation in vitro

In the pig production cycle, the most delicate phase is weaning, a sudden and early change that requires a quick adaptation, at the cost of developing inflammation and oxidation, especially at the intestinal level. In this period, pathogens like enterotoxigenic Escherichia coli (ETEC) contribute to the establishment of diarrhea, with long-lasting detrimental effects. Botanicals and their single bioactive components represent sustainable well-recognized tools in animal nutrition thanks to their wide-ranging beneficial functions. The aim of this study was to investigate the in vitro mechanism of action of a blend of botanicals (BOT), composed of thymol, grapeseed extract, and capsicum oleoresin, in supporting intestinal cell health during inflammatory challenges and ETEC infections. To reach this, we performed inflammatory and ETEC challenges on Caco-2 cells treated with BOT, measuring epithelial integrity, cellular oxidative stress, bacterial translocation and adhesion, gene expression levels, and examining tight junction distribution. BOT protected enterocytes against acute inflammation: while the challenge reduced epithelial tightness by 40%, BOT significantly limited its drop to 30%, also allowing faster recovery rates. In the case of chronic inflammation, BOT systematically improved by an average of 25% the integrity of challenged cells (p < 0.05). Moreover, when cells were infected with ETEC, BOT maintained epithelial integrity at the same level as an effective antibiotic and significantly reduced bacterial translocation by 1 log average. The mode of action of BOT was strictly related to the modulation of the inflammatory response, protecting tight junctions' expression and structure. In addition, BOT influenced ETEC adhesion to intestinal cells (-4%, p < 0.05), also thanks to the reduction of enterocytes' susceptibility to pathogens. Finally, BOT effectively scavenged reactive oxygen species generated by inflammatory and H2O2 challenges, thus alleviating oxidative stress by 40% compared to challenge (p < 0.05). These results support the employment of BOT in piglets at weaning to help manage bacterial infections and relieve transient or prolonged stressful states thanks to the modulation of host-pathogen interaction and the fine-tuning activity on the inflammatory tone.

Dietary lysozyme improves growth performance and intestinal barrier function of weaned piglets

Lysozyme (LZ) is a purely natural, nonpolluting and nonspecific immune factor, which has beneficial effects on the healthy development of animals. In this study, the influences of LZ on the growth performance and intestinal barrier of weaned piglets were studied. A total of 48 weaned piglets (Landrace × Yorkshire, 22 d old) were randomly divided into a control group (basal diet) and a LZ group (0.1% LZ diet) for 19 d. The results showed that LZ could significantly improve the average daily gain (ADG, P < 0.05) and average daily feed intake (ADFI, P < 0.05). LZ also improved the intestinal morphology and significantly increased the expression of occludin in the jejunum (P < 0.05). In addition, LZ down-regulated the expression of interleukin-1β (IL-1β, P < 0.05) and tumor necrosis factor-α (TNF-α, P < 0.05), and inhibited the expression of the genes in the nuclear factor-k-gene binding (NF-κB, P < 0.05) signaling pathway. More importantly, the analysis of intestinal flora showed LZ increased the abundance of Firmicutes (P < 0.05) and the ratio of Firmicutes to Bacteroidota (P = 0.09) at the phylum level, and increased the abundance of Clostridium_sensu_stricto_1 (P < 0.05) and reduced the abundance of Olsenella and Prevotella (P < 0.05) at the genus level. In short, this study proved that LZ could effectively improve the growth performance, relieve inflammation and improve the intestinal barrier function of weaned piglets. These findings provided an important theoretical basis for the application of LZ in pig production.