Clostridium butyricum protects the epithelial barrier by maintaining tight junction protein expression and regulating microflora in a murine model of dextran sodium sulfate-induced colitis

Berberine hydrochloride alleviates chronic prostatitis/chronic pelvic pain syndrome by modifying gut microbiome signaling

ABSTRACT

Chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) is highly prevalent worldwide and poses a significant threat to men's health, particularly affecting young men. However, the exact causes and mechanisms behind CP/CPPS remain unclear, leading to challenges in its treatment. In this research, a CP/CPPS rat model was established with complete Freund's adjuvant (CFA), and berberine hydrochloride was administered through daily gavage to assess its therapeutic effects. The alterations in the gut microbiome induced by CP/CPPS and berberine hydrochloride were investigated through 16S ribosomal RNA sequencing of cecum content and colonic epithelial cells. To investigate the impact of the gut microbiome on CP/CPPS, a pseudo germ-free rat model was established, and fecal microbiome transplantation (FMT) was performed on these rats. In all, berberine hydrochloride demonstrated effective reduction of inflammation and oxidative stress in the prostate, offering significant therapeutic advantages for CP/CPPS. Through analysis of the gut microbiome using 16S ribosome RNA sequencing, distinct differences were observed between CP/CPPS rats and control rats, and Clostridium butyricum was identified as a key bacteria. Pseudo germ-free rats that underwent FMT from CP/CPPS rats or rats treated with berberine hydrochloride displayed varying levels of inflammatory cytokine production, oxidative stress, and activity of associated signaling pathways. In conclusion, the therapeutic potential of berberine hydrochloride in addressing CP/CPPS is highly significant. The gut microbiome has emerged as a critical factor in the development of CP/CPPS and plays a pivotal role in mediating the therapeutic effects of berberine hydrochloride.

Matrine Ameliorates DSS-Induced Colitis by Suppressing Inflammation, Modulating Oxidative Stress and Remodeling the Gut Microbiota

Matrine (MT) possesses anti-inflammatory, anti-allergic and antioxidative properties. However, the impact and underlying mechanisms of matrine on colitis are unclear. The purpose of this research was to examine the protective impact and regulatory mechanism of matrine on dextran sulfate sodium (DSS)-induced ulcerative colitis (UC) in mice. MT alleviated DSS-induced UC by inhibiting weight loss, relieving colon shortening and reducing the disease activity index (DAI). Moreover, DSS-induced intestinal injury and the number of goblet cells were reversed by MT, as were alterations in the expression of zonula occludens-1 (ZO-1) and occludin in colon. Simultaneously, matrine not only effectively restored DSS-induced oxidative stress in colonic tissues but also reduced the production of inflammatory cytokines. Furthermore, MT could treat colitis mice by regulating the regulatory T cell (Treg)/T helper 17 (Th17) cell imbalance. We observed further evidence that MT alleviated the decrease in intestinal flora diversity, reduced the proportion of Firmicutes and Bacteroidetes, decreased the proportion of Proteobacteria and increased the relative abundance of Lactobacillus and Akkermansia in colitis mice. In conclusion, these results suggest that MT may mitigate DSS-induced colitis by enhancing the colon barrier integrity, reducing the Treg/Th17 cell imbalance, inhibiting intestinal inflammation, modulating oxidative stress and regulating the gut microbiota. These findings provide strong evidence for the development and application of MT as a dietary treatment for UC.

Chlorogenic acid protects against intestinal inflammation and injury by inactivating the mtDNA-cGAS-STING signaling pathway in broilers under necrotic enteritis challenge

This study aimed to determine the effects of chlorogenic acid (CGA) on the growth performance, intestinal health, immune response, and mitochondrial DNA (mtDNA)-cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) signaling pathway in broilers under necrotic enteritis (NE) challenge. The 180 one-day-old male Cobb 500 broilers with similar body weight of 44.59 ± 1.39 g were randomly allocated into 3 groups. The groups were control diet (Control group), control diet + NE challenge (NE group), and control diet + 500 mg/kg CGA + NE challenge (NE + CGA group), with 6 replicates per treatment. All broilers except the Control group were given sporulated coccidian oocysts (d 14) and Clostridium perfringens (d 19-21) by oral gavage. Our findings showed that CGA improved the growth performance and intestinal morphology in broilers under NE challenge. CGA supplementation elevated the barrier function in broilers under NE challenge, which reflected in the decreased serum concentrations of D-lactate and diamine oxidase, and upregulated jejunal protein expression of occludin. CGA supplementation also improved the immune function, which reflected in the increased concentrations and gene expressions of anti-inflammatory factors, and decreased concentrations and gene expressions of proinflammatory factors. CGA supplementation further enhanced intestinal cell proliferation and differentiation, which manifested in the increased number of goblet cells and positive cells of proliferating cell nuclear antigen on d 28 and 42. Furthermore, CGA supplementation decreased the mtDNA (d 42) and mitochondrial reactive oxygen species levels (d 28 and 42), and increased the mitochondrial membrane potential (d 42) and mitochondrial complex I (d 28 and 42) or III (d 28) activity. Broilers challenged with NE had upregulated jejunal protein expressions of cGAS, phospho-TANK-binding kinase 1, and phospho-interferon regulatory factor 7 compared with the Control group, which were downregulated after CGA supplementation. In conclusion, dietary supplementation CGA could protect against intestinal inflammation and injury by reducing the leakage of mtDNA and inactivating the cGAS-STING signaling pathway in broilers under NE challenge.

Effect of the Combination of Clostridium butyricum and Mycelium of Phellinus igniarius on Intestinal Microbiota and Serum Metabolites in DSS-Induced Colitis

Clostridium butyricum (CB) and Phellinus igniarius (PI) have anti-inflammatory, immune regulation, anti-tumor, and other functions. This study aimed to explore the therapeutic effect of CB and mycelium of PI (MPI) alone and in combination on colitis mice induced by dextran sodium sulfate (DSS). Mice were randomly assigned to five groups: (1) control (CTRL), (2) DSS, (3) CB, (4) MPI, and (5) CB + MPI (CON). The weight of the mice was recorded daily during the experiment, and the length of the colon was measured on the last day of the experiment. The colons were collected for hematoxylin and eosin staining, colon contents were collected for intestinal flora analysis, and serum was collected for metabolite analysis. The results showed that compared with the DSS group, CB, MPI, and CON treatments inhibited the weight loss and colon length shortening caused by DSS, significantly increased the concentrations of interleukin (IL)-4, IL-10, and superoxide dismutase, and significantly decreased the concentrations of IL-6, tumor necrosis factor-α, and myeloperoxidase. Gene sequence analysis of 16S rRNA showed that CB, MPI, and CON treatments changed the composition and structure of intestinal microorganisms. Metabolome results showed that CB, MPI, and CON treatments changed serum metabolites in DSS-treated mice, including dodecenoylcarnitine, L-urobilinogen, and citric acid. In conclusion, CB, MPI, and CON treatments alleviated DSS-induced colitis in mice by regulating intestinal flora and metabolites, with the CON group having the best effect.

Effects of Huzhangoside C on Dextran Sodium Sulfate-Stimulated Colitis in Mice

Chronic inflammation is a major risk factor for cancer. Inflammatory bowel disease (IBD) is a chronic inflammatory disease of the gastrointestinal tract, ultimately leading to a breakdown of intestinal barrier function. Clematis florida var. plena is a folk prescription used to treat inflammation and rheumatism in She pharmacy. The bioactivity of C. florida var. plena is primarily due to triterpene saponins. Huzhangoside C (HZ) is an active component of C. florida var. plena. In this study, the anti-inflammatory effect of HZ on a mouse colitis model induced by dextran sulfate sodium (DSS) was investigated. Result indicated a notable reduction in body weight loss and colon length shortening in HZ-mediated mice compared to DSS-stimulated control mice. Furthermore, inflammatory signaling mechanisms involving interleukin-6 and tumor necrosis factor-α were suppressed in HZ-treated mice. HZ treatment significantly suppressed the expression of nuclear factor kappa B (NF-κB), STAT3, and iNOS in colon tissue. After HZ treatment, malondialdehyde and nitric oxide levels were significantly decreased, while Nrf-2, superoxide dismutase, and glutathione expression levels were notably improved. The result indicated that HZ could activate the Nrf-2 signal cascade, inhibit the expression of NF-κB, eNOS, and STAT3, and enhance the intestinal barrier function of DSS stimulated ulcerative colitis intestinal injury. The results suggest that HZ is potential anti-inflammatory agent for treating IBD.

Protective Effect and Mechanism of Aspirin Eugenol Ester on Lipopolysaccharide-Induced Intestinal Barrier Injury

Intestinal inflammation is a complex and recurrent inflammatory disease. Pharmacological and pharmacodynamic experiments showed that aspirin eugenol ester (AEE) has good anti-inflammatory, antipyretic, and analgesic effects. However, the role of AEE in regulating intestinal inflammation has not been explored. This study aimed to investigate whether AEE could have a protective effect on LPS-induced intestinal inflammation and thus help to alleviate the damage to the intestinal barrier. This was assessed with an inflammation model in Caco-2 cells and in rats induced with LPS. The expression of inflammatory mediators, intestinal epithelial barrier-related proteins, and redox-related signals was analyzed using an enzyme-linked immunosorbent assay (ELISA), Western blotting, immunofluorescence staining, and RT-qPCR. Intestinal damage was assessed by histopathological examination. Changes in rat gut microbiota and their functions were detected by the gut microbial metagenome. AEE significantly reduced LPS-induced pro-inflammatory cytokine levels (p < 0.05) and oxidative stress levels in Caco-2 cells and rats. Compared with the LPS group, AEE could increase the relative expression of Occludin, Claudin-1, and zonula occludens-1 (ZO-1) and decrease the relative expression of kappa-B (NF-κB) and matrix metalloproteinase-9. AEE could significantly improve weight loss, diarrhea, reduced intestinal muscle thickness, and intestinal villi damage in rats. Metagenome results showed that AEE could regulate the homeostasis of the gut flora and alter the relative abundance of Firmicutes and Bacteroidetes. Flora enrichment analysis indicated that the regulation of gut flora with AEE may be related to the regulation of glucose metabolism and energy metabolism. AEE could have positive effects on intestinal inflammation-related diseases.

Effects of Lactobacillus plantarum HW1 on Growth Performance, Intestinal Immune Response, Barrier Function, and Cecal Microflora of Broilers with Necrotic Enteritis

The purpose of the study was to investigate the effects of Lactobacillus plantarum HW1 on growth performance, intestinal immune response, barrier function, and cecal microflora of broilers with necrotic enteritis. In total, 180 one-day-old male Cobb 500 broilers were randomly allocated into three groups comprising a non-infected control (NC) group, basal diet + necrotic enteritis challenge (NE) group, and basal diet + 4 × 106 CFU/g Lactobacillus plantarum HW1 + necrotic enteritis challenge (HW1) group. Broilers in the NE and HW1 groups were orally given sporulated coccidian oocysts at day 14 and Clostridium perfringens from days 19 to 21. The results showed that the HW1 treatment increased (p < 0.05) the average daily gain of broilers from days 15 to 28 and from days 0 to 28 compared with the NE group. Moreover, the HW1 treatment decreased (p < 0.05) the oocysts per gram of excreta, intestinal lesion scores, ileal interleukin (IL) 1β and tumor necrosis factor α levels, and serum D-lactic acid and diamine oxidase levels, while increasing (p < 0.05) the ileal IL-10 level, thymus index, and protein expressions of ileal occludin and ZO-1. Additionally, the HW1 treatment decreased (p < 0.05) the jejunal and ileal villus height, jejunal villus height/crypt depth value, and cecal harmful bacterial counts (Clostridium perfringens, Salmonella, Escherichia coli, and Staphylococcus aureus), and increased (p < 0.05) the cecal Lactobacillus count. In conclusion, dietary supplementation with 4 × 106 CFU/g Lactobacillus plantarum HW1 could relieve necrotic enteritis infection-induced intestinal injury and improve growth performance in broilers by improving intestinal barrier function and regulating intestinal microbiology.

The possible effect of lycopene in ameliorating experimentally induced ulcerative colitis in adult male albino rats (A histological, immunohistochemical, and ultrastructural study)

Ulcerative colitis (UC) is considered a long-term inflammatory disorder worldwide. Its pathogenesis is associated with reduced antioxidant capacity. Lycopene (LYC) is a powerful antioxidant with strong free radical scavenging property. The present work has done to assess changes of colonic mucosa in induced UC and the possible ameliorative effects of LYC. Forty-five adult male albino rats were randomly divided into four groups: group I (control), group II was given 5 mg/kg/day (LYC) by oral gavage for 3 weeks. Group III (UC) was received single intra-rectal injection of acetic acid. Group IV (LYC+UC) received LYC in same dose and duration as before and acetic acid on 14th day of the experiment. UC group showed loss of surface epithelium with destructed crypts. Congested blood vessels with heavy cellular infiltration were observed. Significant decrease in goblet cell numbers and the mean area percentage of ZO-1 immunoexpression were noticed. Significant increase in the mean area percentage of collagen and the mean area percentage of COX-2 were also noticed. Ultrastructural changes were matched with light microscopic results that showed abnormal destructive columnar and goblet cells. Histological, immunohistochemical, and ultrastructural findings in group IV supported the ameliorative role of LYC against destructive changes induced by UC.

Clostridium butyricum Can Promote Bone Development by Regulating Lymphocyte Function in Layer Pullets

Bone health problems are a serious threat to laying hens; microbiome-based therapies, which are harmless and inexpensive, may be an effective solution for bone health problems. Here, we examined the impacts of supplementation with Clostridium butyricum (CB) on bone and immune homeostasis in pullets. The results of in vivo experiments showed that feeding the pullets CB was beneficial to the development of the tibia and upregulated the levels of the bone formation marker alkaline phosphatase and the marker gene runt-related transcription factor 2 (RUNX2). For the immune system, CB treatment significantly upregulated IL-10 expression and significantly increased the proportion of T regulatory (Treg) cells in the spleen and peripheral blood lymphocytes. In the in vitro test, adding CB culture supernatant or butyrate to the osteoblast culture system showed no significant effects on osteoblast bone formation, while adding lymphocyte culture supernatant significantly promoted bone formation. In addition, culture supernatants supplemented with treated lymphocytes (pretreated with CB culture supernatants) stimulated higher levels of bone formation. In sum, the addition of CB improved bone health by modulating cytokine expression and the ratio of Treg cells in the immune systems of layer pullets. Additionally, in vitro CB could promote the bone formation of laying hen osteoblasts through the mediation of lymphocytes.

New Advances in Improving Bone Health Based on Specific Gut Microbiota

The gut microbiota has been shown to play an important role in the pathogenesis of various diseases, including metabolic diseases, cardiovascular diseases, and cancer. Recent studies suggest that the gut microbiota is also closely associated with bone metabolism. However, given the high diversity of the gut microbiota, the effects of different taxa and compositions on bone are poorly understood. Previous studies demonstrated that the mechanisms underlying the effects of the gut microbiota on bone mainly include its modulation of nutrient absorption, intestinal permeability, metabolites (such as short-chain amino acids), immune responses, and hormones or neurotransmitters (such as 5-hydroxytryptamine). Several studies found that external interventions, such as dietary changes, improved bone health and altered the composition of the gut microbiota. This review summarises the beneficial gut bacteria and explores how dietary, natural, and physical factors alter the diversity and composition of the gut microbiota to improve bone health, thereby providing potential new insight into the prevention of osteoporosis.

DNMT3a-Mediated Enterocyte Barrier Dysfunction Contributes to Ulcerative Colitis via Facilitating the Interaction of Enterocytes and B Cells

Objective

Dysfunction of the enterocyte barrier is associated with the development of ulcerative colitis (UC). This study was aimed at exploring the effect of DNMT3a on enterocyte barrier function in the progression of UC and the underlying mechanism.

Method

Mice were given 3.5% dextran sodium sulphate (DSS) in drinking water to induce colitis. The primary intestinal epithelial cells (IECs) were isolated and treated with lipopolysaccharide (LPS) to establish an in vitro inflammatory model. We detected mouse clinical symptoms, histopathological damage, enterocyte barrier function, B cell differentiation, DNA methylation level, and cytokine production. Subsequently, the effect of DNMT3a from IECs on B cell differentiation was explored by a cocultural experiment.

Result

DSS treatment significantly reduced the body weight and colonic length, increased disease activity index (DAI), and aggravated histopathological damage. In addition, DSS treatment induced downregulation of tight junction (TJ) protein, anti-inflammatory cytokines (IL-10 and TGF-β), and the number of anti-inflammatory B cells (CD1d+) in intestinal epithelial tissues, while upregulated proinflammatory cytokines (IL-6 and TNF-α), proinflammatory B cells (CD138+), and DNA methylation level. Further in vitro results revealed that DNMT3a silencing or TNFSF13 overexpression in IECs partly abolished the result of LPS-induced epithelial barrier dysfunction, as well as abrogated the effect of IEC-regulated B cell differentiation, while si-TACI transfection reversed these effects. Moreover, DNMT3a silencing decreased TNFSF13 methylation level and induced CD1d+ B cell differentiation, and the si-TNFSF13 transfection reversed the trend of B cell differentiation but did not affect TNFSF13 methylation level.

Conclusion

Our study suggests that DNMT3a induces enterocyte barrier dysfunction to aggravate UC progression via TNFSF13-mediated interaction of enterocyte and B cells.

Clostridium butyricum therapy for mild-moderate Clostridioides difficile infection and the impact of diabetes mellitus

The therapeutic effect of Clostridium butyricum for adults with Clostridioides difficile infection (CDI) was investigated. A retrospective study was conducted in medical wards of Tainan Hospital, Ministry of Health and Welfare, between January 2013 and April 2020. The disease severity of CDI was scored based on the Clinical Practice Guidelines of the IDSA/SHEA. Treatment success was defined as the resolution of diarrhea within six days of a therapeutic intervention without the need to modify the therapeutic regimen. In total, 241 patients developed CDI during hospitalization in the study period. The treatment success rates for the 99 patients with mild-moderate CDI among them were as follows: metronidazole, 69.4%; C. butyricum, 68.2%; metronidazole plus C. butyricum, 66.7%; and oral vancomycin, 66.7% (p=1.00). Patients with treatment success were less likely to have diabetes mellitus than those with treatment failure (38.2% vs. 61.3%, p=0.05). Patients treated with C. butyricum alone or in combination with metronidazole had shorter durations of diarrhea than those treated with metronidazole alone (3.1 ± 2.0 days or 3.5 ± 2.4 days vs. 4.2 ± 3.5 days; p=0.43 or 0.71), although the differences were not statistically significant. In conclusion, the treatment success rate of C. butyricum alone or in combination with metronidazole for patients with CDI was non inferior to that of metronidazole alone. The presence of diabetes mellitus in affected individuals is a risk factor for treatment failure.

Overview of the Importance of Biotics in Gut Barrier Integrity

Increased gut permeability is suggested to be involved in the pathogenesis of a growing number of disorders. The altered intestinal barrier and the subsequent translocation of bacteria or bacterial products into the internal milieu of the human body induce the inflammatory state. Gut microbiota maintains intestinal epithelium integrity. Since dysbiosis contributes to increased gut permeability, the interventions that change the gut microbiota and correct dysbiosis are suggested to also restore intestinal barrier function. In this review, the current knowledge on the role of biotics (probiotics, prebiotics, synbiotics and postbiotics) in maintaining the intestinal barrier function is summarized. The potential outcome of the results from in vitro and animal studies is presented, and the need for further well-designed randomized clinical trials is highlighted. Moreover, we indicate the need to understand the mechanisms by which biotics regulate the function of the intestinal barrier. This review is concluded with the future direction and requirement of studies involving biotics and gut barrier.

Licoflavone B, an isoprene flavonoid derived from licorice residue, relieves dextran sodium sulfate-induced ulcerative colitis by rebuilding the gut barrier and regulating intestinal microflora

Ulcerative colitis (UC) is a major inflammatory disease worldwide. We previously demonstrated that licorice residue flavones (LFs) showed satisfactory efficacy in the treatment of UC. Therefore, research into the ingredients of LFs may lead to the discovery of novel anti-UC targets. In the current study, we separated licoflavone B (LB) from LFs and administered it to dextran sodium sulfate (DSS)-exposed C57BL/6 mice for 14 days. Our results demonstrated that high dose LB (120mg/kg) significantly prevented DSS-induced weight loss, disease activity index (DAI) increase, histological damage, and colonic inflammation, indicating that LB has ameliorative effects on UC. We also investigated the composition of the intestinal barrier and microflora in an attempt to explore the mechanisms of LB against UC. As a result, we found that LB preserved the integrity of the colonic barrier by inhibiting colonic cell apoptosis and protecting the expression of occludin, claudin-1, and ZO-1. Moreover, LB reshaped the microflora composition by suppressing harmful bacteria (Enterococcus et al.) and boosting beneficial microorganisms (Bacteroides et al.). Further molecular exploration implied that LB exerted anti-UC activity through blocking the MAPK pathway. Here, we explored anti-UC activity of LB for the first time and clarified its mechanisms. These results will provide valuable clues for the discovery of novel anti-UC agents.

L-citrulline enriched fermented milk with Lactobacillus helveticus attenuates dextran sulfate sodium (DSS) induced colitis in mice

Inflammatory bowel disease (IBD) is a group of chronic inflammatory gastrointestinal diseases that causes worldwide suffering. L. helveticus is a probiotic that can enhance intestinal barrier function via alleviation of excessive inflammatory response. Citrulline, a functional amino acid, has been reported to stimulate muscle synthesis and to function with a prebiotic-like action with certain Lactobacillus strains. The aim of this study was to investigate the potential synergistic effect of combining L. helveticus and citrulline on protection against damage induced by dextran sulfate sodium (DSS) in a mouse model. 6-week-old male C57BL/6J mice were fed with DSS water and randomly divided for administering with different milk treatments: 1) plain milk (control or DSS control), 2) 1% (w/v) citrulline enriched milk (Cit_milk), 3) milk fermented with L. helveticus (LHFM) and 4) DSS+milk fermented with L. helveticus with 1% (w/v) citrulline (Cit_LHFM). The treatment effects on the survival and macroscopic and microscopic signs were examined. All treatments presented different degrees of protective effects on attenuating the damages induced by DSS. All treatments reduced the body weight loss, disease activity index (DAI), histological scores, pro-inflammatory cytokine expression (IL-6, TNF-α and IFN-γ) and production (IL-4) (all P <0.05) and the tight junction (TJ) protein (zonula occluden-1 (ZO-1) expression. LHFM and Cit_LHFM improved survival rate (both at P<0.05). Particularly, Cit_LHFM showed greater effects on protecting the damages induced by DSS, especially in ameliorating colonic permeability, TJ protein (ZO-1, occludin and claudin-1) expression and distribution as well as in reducing IL-4 and IL-17 expression (all P <0.05). Our findings suggested that the combination of and citrulline had significant synergistic effect on protecting against injury from DSS-induced colitis. Therefore, citrulline enriched L. helveticus fermented milk is suggested to be a potential therapy for treating IBD.

Keratin 1 maintains the intestinal barrier in ulcerative colitis

BACKGROUND

The intestinal mechanical barrier plays a key role in the pathogenesis of ulcerative colitis (UC). Our previous study showed keratin 1 (KRT1) was downregulated in UC, but the mechanism by which KRT1 affects the intestinal barrier remains unknown.

OBJECTIVES

To explore the mechanism of KRT1 in the intestinal barrier in UC.

METHODS

Colonic tissues were collected from 20 UC patients before and after mucosal healing (MH) and 15 healthy controls. The expression of KRT1 was measured by PCR, western blotting and immunohistochemistry (IHC). A dextran sulfate sodium (DSS)-induced colitis model was established in krt1 transgenic (TG) mice, and the mice were treated with methylprednisolone (MP) to explore the role of KRT1 in the intestinal barrier. Inflammation was evaluated through the DAI score, colon, spleen and H&E. The expression of KRT1 and tight junction (TJ) proteins in mouse was analysed by the same methods.

RESULTS

The transcription and expression of KRT1 in UC was decreased and recovered after MH but did not reach the level of the healthy controls. Similar to the clinical results, the expression of krt1 was decreased in DSS-induced colitis and upregulated after MP. Moreover, the krt1 TG group exhibited less inflammation than wild-type (WT) group. The expression of Occludin and ZO-1 decreased after DSS induction, the decreases in Occludin and ZO-1 in the krt1 TG group were lower than WT group, which was significantly increased after MP, while the expression of Claudin-2 exhibited the opposite effect.

CONCLUSIONS

Keratin 1 maintains the intestinal barrier by upregulating TJ proteins in UC.

Clostridium butyricum CB1 up-regulates FcRn expression via activation of TLR2/4-NF-κB signaling pathway in porcine small intestinal cells

The neonatal Fc receptor (FcRn) mediates the bidirectional transport of immunoglobulin G (IgG) across hyperpolarized epithelial cells. Overexpression of FcRn increases serum IgG and humoral immune response. Probiotics can improve the host's serum and intestinal mucosal IgG. However, whether probiotics regulate FcRn and its specific mechanism are still unclear. Our research showed that heat inactivated Clostridium butyricum CB1 (heat-inactivated CB1) up-regulated FcRn expression in porcine small intestinal epithelial (IPI-2I) cells. Furthermore, heat-inactivated CB1 stimulation activated the nuclear factor kappa B (NF-κB) signaling pathway. Moreover, FcRn expression decreased after blocking the NF-κB signaling pathway by NF-κB inhibitor BAY11-7028, suggesting that heat-inactivated CB1 induced FcRn expression via the NF-κB signaling pathway. Using small interfering RNAs (siRNAs), we found that knockdown of TLR2/4, MyD88 and TRIF reduced NF-κB activity induced by heat-inactivated CB1, as well as up-regulation of FcRn expression after heat-inactivated CB1 stimulation. Taken together, our data indicated that heat-inactivated CB1 up-regulated FcRn expression via TLR2/4-MyD88/TRIF-NF-κB signaling pathway. These results provided a new perspective for us to understand the enhancement of C. butyricum on intestinal mucosal immunity.

Enterococcus faecium HDRsEf1 inhibits LPS-induced downregulation of ZO-1 expression via TLR2/4-mediated JNK/AP-1 signalling pathways

AIMS

ZO-1 is a key regulatory tight junction protein that plays an important role in maintaining gastrointestinal health. In this study, we investigated the protective effect and regulation mechanism of the probiotic Enterococcus faecium HDRsEf1 on tight junction protein ZO-1 at the cellular and molecular levels.

METHODS AND RESULTS

We established LPS-induced intestinal epithelial cell injury model, and detected the protective effect of HDRsEf1 on ZO-1 in IPEC-J2 cells by Real-time PCR and Western blot. The results showed that HDRsEf1 inhibited the downregulation of ZO-1 expression induced by LPS. HDRsEf1 stabilized the destruction of the ZO-1 structure caused by LPS in an immunofluorescence assay. Through gene overexpression and siRNA interference tests, we found that transcription factor AP-1 inhibited the level of ZO-1 expression. Silencing experiment further supported that the protective effect of HDRSEF1 might mediated by suppression of LPS-provoked activation of ASK1/MKK7/JNK signalling pathways. In addition, HDRsEf1 could stabilize ZO-1 expression by increasing TLR2 expression and competing with LPS for the TLR4 binding site. More interestingly, we also found that HDRsEf1 could stabilize ZO-1 expression through inhibiting the production of TNF-α induced by LPS.

CONCLUSIONS

HDRsEf1 could protect the IPEC-J2 cell against LPS induced down-regulation of ZO-1 expression by inhibiting the activation of TLR2/4-mediated JNK-AP-1 and signalling cascade and the production of TNF-α.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study can provide a theoretical basis for probiotics to regulate the expression of intestinal tight junction proteins, and supply technical support for probiotics to prevent and treat animal intestinal infectious diseases.

Molecular characterization, developmental expression, and modulation of occludin by early intervention with Clostridium butyricum in Muscovy ducks

Occludin is an important component of tight junction proteins and has been extensively studied in animals such as mice, chickens, geese, and pigs. As one of the most important waterfowl species in China, Muscovy duck (Cairina moschata) is an important economic animal for meat. However, research on the occludin gene in Muscovy duck is lacking. In the present study, Muscovy duck occludin cDNA was cloned for the first time. The length of the cDNA was 1,699 bp, and it showed a high sequence similarity with the Anser cygnoides domesticus and Gallus gallus occludin genes. The occludin gene was differentially expressed in the tissues of healthy ducks. The highest and lowest expressions of occludin were observed in the crop and the spleen, respectively. After the oral administration of Clostridium butyricum (CB), the occludin expression in the ileum of 7-day-old Muscovy ducks was significantly upregulated and subsequently showed a decreasing trend in 14-day-old Muscovy ducks. Under the early intervention of CB, no significant difference was observed in the occludin expression of cecum between the control and CB group. Collectively, these results suggest that CB plays an important role in regulating the expression of the occludin gene in Muscovy ducks, and adding CB in feed may maintain the intestinal barrier of ducks by regulating the expression of occludin.

Clostridium butyricum Alleviates Gut Microbiota Alteration-Induced Bone Loss after Bariatric Surgery by Promoting Bone Autophagy

Bariatric surgery is the most common and effective treatment of severe obesity; however, these bariatric procedures always result in detrimental effects on bone metabolism by underlying mechanisms. This study aims to investigate the skeletal response to bariatric surgery and to explore whether Clostridium butyricum alleviates gut microbiota alteration-induced bone loss after bariatric surgery. Consequently, male SD rats received Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG) surgery, respectively, followed by body weight recording. The bone loss after bariatric surgery was further determined by dual-energy X-ray absorptiometry (DXA), micro-CT measurement, histologic analyses, and Western blot. Besides, 16S rDNA gene sequencing was performed to determine the gut microbiota alteration after surgery, and intervention with fecal microbiota from RYGB donor was conducted in obese SD rats, followed by C. butyricum administration. Accordingly, rats in the RYGB and SG groups maintained sustained weight loss, and DXA and micro-CT measurement further demonstrated significant bone loss after bariatric surgery. Besides, histologic and Western blot analyses validated enhanced osteoclastogenesis and inhibited osteoblastogenesis and defective autophagy after surgery. The 16S rDNA gene sequencing suggested a significant alteration of gut microbiota composition in the RYGB group, and intervention with fecal microbiota from RYGB donor further determined that this kind of alteration contributed to the bone loss after RYGB. Meanwhile, C. butyricum might protect against this postoperative bone loss by promoting osteoblast autophagy. In summary, this study suggests novel mechanisms to clarify the skeletal response to bariatric surgery and provides a potential candidate for the treatment of bone disorder among bariatric patients. SIGNIFICANCE STATEMENT: The significance of this study is the discovery of obvious bone loss and defective autophagy after bariatric surgery. Besides, it is revealed that gut microbiota alterations could be the reason for impaired bone mass after bariatric surgery. Furthermore, Clostridium butyricum could alleviate the gut microbiota alteration-induced bone loss after bariatric surgery by promoting osteoblast autophagy.

Dysbiosis of the intestinal microbiome as a component of pathophysiology in the inborn errors of metabolism

Inborn errors of metabolism (IEMs) represent monogenic disorders in which specific enzyme deficiencies, or a group of enzyme deficiencies (e.g., peroxisomal biogenesis disorders) result in either toxic accumulation of metabolic intermediates or deficiency in the production of key end-products (e.g., low cholesterol in Smith-Lemli-Opitz syndrome (Gedam et al., 2012 [1]); low creatine in guanidinoacetic acid methyltransferase deficiency (Stromberger, 2003 [2])). Some IEMs can be effectively treated by dietary restrictions (e.g., phenylketonuria (PKU), maple syrup urine disease (MSUD)), and/or dietary intervention to remove offending compounds (e.g., acylcarnitine excretion with the oral intake of l-carnitine in the disorders of fatty acid oxidation). While the IEMs are predominantly monogenic disorders, their phenotypic presentation is complex and pleiotropic, impacting multiple physiological systems (hepatic and neurological function, renal and musculoskeletal impairment, cardiovascular and pulmonary activity, etc.). The metabolic dysfunction induced by the IEMs, as well as the dietary interventions used to treat them, are predicted to impact the gut microbiome in patients, and it is highly likely that microbiome dysbiosis leads to further exacerbation of the clinical phenotype. That said, only recently has the gut microbiome been considered as a potential pathomechanistic consideration in the IEMs. In this review, we overview the function of the gut-brain axis, the crosstalk between these compartments, and the expanding reports of dysbiosis in the IEMs recently reported. The potential use of pre- and probiotics to improve clinical outcomes in IEMs is also highlighted.

Maintaining intestinal structural integrity is a potential protective mechanism against inflammation in goose fatty liver

Overfeeding causes severe steatosis but not inflammation in goose liver, suggesting existence of protective components. Previous studies have shown that some intestinal microbes and their metabolites damage intestinal structural integrity and function, thus causing inflammation in the development of human and mouse nonalcoholic fatty liver disease. Therefore, this study hypothesizes that intestinal structural integrity of goose is maintained during overfeeding, which may provide goose fatty liver a protective mechanism against inflammation. To test this hypothesis, 48 seventy-day-old healthy Landes male geese were overfed (as overfeeding group) or normally fed (as control group). Blood and intestine (jejunum, ileum, and cecum) samples were harvested on the 12^th and 24^th d of overfeeding. Data showed that goose fatty liver was successfully induced by 24 d of overfeeding. Hematoxylin-eosin staining analysis indicated that the arrangement of villi and crypts in the intestine was orderly, and the intestinal structure was intact with no pathological symptoms in the 2 groups. Enzyme-linked immunosorbent assay and quantitative PCR analysis indicated no significant differences in the expression of tight junction and inflammation-related genes as well as plasma lipopolysaccharide concentration between the groups. Ileal hypertrophy and cecal atrophy were observed in the overfed vs. control geese, probably because of change of sphingolipid metabolism. Activation of apoptotic pathway may help cecum avoid necrosis-induced inflammation. In conclusion, healthy and intact intestine provides a layer of protection for goose fatty liver against inflammation. Sphingolipid metabolism may be involved in the adaptation of ileum and cecum to overfeeding. The hypertrophy of ileum makes it an important contributor to the development of goose fatty liver. The atrophy and decline in the function of cecum may be caused by apoptosis induced by overfeeding.

Baicalin-Copper Complex Modulates Gut Microbiota, Inflammatory Responses, and Hormone Secretion in DON-Challenged Piglets

Simple Summary

Deoxynivalenol (DON) is the most common mycotoxin contaminant in the agriculture industry worldwide. Copper is very efficacious in promoting growth performance and improving feed remuneration, and baicalin may alleviate oxidative stress and inflammatory responses in humans and animals. We speculated that the combined effect of baicalin and copper would have some effect in DON-challenged piglets. The present study examined the effects of a baicalin-copper complex on inflammatory responses, hormone secretion, and gut microbiota in DON challenged piglets. These findings provide new application prospects in piglets involving the combination of baicalin and copper.

Abstract

The present experiment assessed the inflammatory responses, hormone secretion, and gut microbiota of weanling piglets administered baicalin-copper complex (BCU) or deoxynivalenol (DON) supplementation diets. Twenty-eight piglets were randomly assigned to four groups: control diet (Con group), a 4 mg DON/kg diet (DON group), a 5 g BCU/kg diet (BCU group), a 5 g BCU + 4 mg DON/kg diet (DBCU group). After 14 days, the results showed that dietary BCU supplementation remarkably increased the relative abundance of Clostrium bornimense and decreased the relative abundance of Lactobacillus in the DBCU group (p < 0.05). BCU decreased the serum concentration of IgG, IL-2, IFN-γ, and IgA in DON treated piglets (p < 0.05), and promoted the serum concentration of IL-1β, IgG, IL-2, IFN-γ, IgA, IL-6, IgM, and TNFα in normal piglets (p < 0.05). BCU increased the concentrations of serum IGF1, insulin, NPY, GLP-1, and GH, and decreased the concentrations of serum somatostatin in no DON treated piglets (p < 0.05). Dietary BCU supplementation significantly promoted the secretion of somatostatin, and inhibited the secretion of leptin in piglets challenged with DON (p < 0.05). BCU regulated the expression of food intake-related genes in the hypothalamus and pituitary of piglets. Collectively, dietary BCU supplementation alleviated inflammatory responses and regulated the secretion of appetite-regulating hormones and growth-axis hormones in DON challenged piglets, which was closely linked to changes of intestinal microbes.

Protective Effects of Clostridium Butyricum in a Murine Model of Dextran Sodium Sulfate-Induced Colitis That Involve Inhibition of the TLR2 Signaling Pathway and T Helper 17 Cells

BACKGROUND

This study aimed to investigate the role of Clostridium butyricum (C. butyricum) in conjunction with the Toll-like receptor2 (TLR2) signaling pathway and T helper 17 (Th17) cells in dextran sodium sulfate (DSS)-induced colitis in mice.

METHODS

Forty 8-week-old BALB/c mice were randomly divided into 5 groups of 8 mice for 7 days: control, DSS (5% DSS), DSS+C. butyricum (1 × 10⁹ CFU), DSS+C. butyricum (1 × 10⁸ CFU) and DSS+C. butyricum (1 × 10⁷ CFU) groups. We assessed the disease activity index (DAI) and histological damage scores. The expression levels of TLR2, myeloid differentiation factor 88 (MyD88), nuclear factor kappa-B p65 (NF-κBp65), interleukin (IL) 17 (IL17), IL23 and retineic acid receptor related orphan nuclear receptor gamma t (RORγt) were determined through immunohistochemical staining, western blot and quantitative real-time PCR (qRT-PCR). The expression levels of CD3⁺CD4⁺IL17⁺ cells in peripheral blood were measured by flow cytometry.

RESULTS

C. butyricum dose-dependently decreased DAI and histological damage scores in DSS mice and down-regulated the mRNA and protein levels of TLR2, MyD88 and NF-κBp65 in mouse colon tissue (all P < 0.05). In addition, C. butyricum dose-dependently decreased the levels of CD3⁺CD4⁺IL17⁺ cells in peripheral blood and down-regulated the mRNA and protein levels of IL17, IL23 and RORγt in mouse colon tissue (all P < 0.05). Moreover, the effect of C. butyricum on TLR2 was positively correlated with IL17, IL23 and RORγt.

CONCLUSIONS

C. butyricum exerts a dose-dependently protective effect on acute intestinal inflammation induced by DSS in mice, by inhibiting the TLR2 signaling pathway, down-regulating the expression of IL23 and RORγt, and inhibiting the secretion of IL17.

Heat shock transcription factor 2 inhibits intestinal epithelial cell apoptosis through the mitochondrial pathway in ulcerative colitis

UC is a chronic inflammatory disease of the colonic mucosa and lacks effective treatments because of unclear pathogenesis. Excessive apoptosis of IECs damages the intestinal epithelial barrier and is involved in the progression of UC, but the mechanism is unknown. HSPs are important in maintaining homeostasis and regulate apoptosis through the mitochondrial pathway. In our previous studies, HSF2, an important regulator of HSPs, was highly expressed in UC patients and negatively correlated with inflammation in mice and IECs. Therefore, we hypothesized that HSF2 may protect against intestinal mucositis by regulating the apoptosis of IECs. In this study, a DSS-induced colitis model of hsf2^-/- mice was used to explore the relationship between HSF2 and apoptosis in IECs for the first time. The expression of HSF2 increased in the WT + DSS group compared with that in the WT + H₂O group. Moreover, the extent of apoptosis was more severe in the KO + DSS group than in the WT + DSS group. The results showed that HSF2 was negatively correlated with apoptosis in vivo. The expression of HSF2 in Caco-2 cells was changed by lentiviral transfection, and the expression of Bax, cytoplasmic Cyto-C, Cleaved Caspase-9 and Cleaved Caspase-3 were negatively correlated with the different levels of HSF2. These results suggest that HSF2 negatively regulates apoptosis of IECs through the mitochondrial pathway. This may be one of the potential mechanisms to explain the protective role of HSF2 in UC.

Oral administration of Lactobacillus plantarum 06CC2 prevents experimental colitis in mice via an anti‑inflammatory response

Dysbiosis of the enteric microbiota causes gastrointestinal diseases, including colitis. The present study investigated the beneficial effect of Lactobacillus plantarum 06CC2 in experimental colitis in mice. An experimental colitis model in C57BL6 mice was induced using dextran sulfate sodium. Mice were orally administered 06CC2 (06CC2 group) or PBS only (control group) by gavage. The disease activity index (DAI), histological grading, and colon tissue and colonic lamina propria mononuclear cells (LPMCs) were examined macroscopically and histopathologically, and the expression levels of inflammation‑associated cytokines (IL‑6, IL‑12, TNF‑α and IL‑10) in these samples were determined. Compared with the control group, the 06CC2 group exhibited a significantly lower DAI (1.5±0.8 vs. 0.2±0.3, respectively; P<0.05) and pathology score (6.3±1.5 vs. 3.8±1.3, respectively; P<0.05). IL‑10 expression in colonic LPMCs was higher in the 06CC2 group than in the control group, although there was no significant difference in IFN‑γ, IL‑6 or IL‑12 expression in colonic LPMCs between the two groups. In addition, 06CC2 stimulated the production of IL‑10 from CD11b‑positive cells and CD11c‑positive cells in the colon. The 06CC2 strain induced IL‑10 production in the colon and attenuated colon inflammation.

Andrographolide derivative AL-1 reduces intestinal permeability in dextran sulfate sodium (DSS)-induced mice colitis model

AIMS

This study was to assess whether andrographolide derivative (AL-1) could restore mucosal homeostasis and regulate tight junctions through MLCK-dependent pathway in DSS-induced colitis mice.

MAIN METHODS

Colitis mice model was induced by daily administration of 2.5% DSS for seven days. The therapeutic effect was determined by evaluating the histopathological changes and the pro-inflammatory cytokine level. In addition, the effects of AL-1 on tight junctions were examined by immunohistochemistry and Western blot. The expressions of factors in MLCK-dependent pathway were evaluated by immunofluorescence and Western blot.

KEY FINDINGS

AL-1 protected the intestinal barrier function in DSS-induced colitis mice. These protective effects were achieved by maintaining the normal mucus secretion and preserving tight junctions via suppression of the MLCK-dependent pathway.

SIGNIFICANCE

AL-1 could prevent the increase in the DSS-induced intestinal permeability. These data indicated that AL-1 could be a promising agent for UC treatment.

The effect of dietary supplementation with Clostridium butyricum on the growth performance, immunity, intestinal microbiota and disease resistance of tilapia (Oreochromis niloticus)

This study was conducted to assess the effects of dietary Clostridium butyricum on the growth, immunity, intestinal microbiota and disease resistance of tilapia (Oreochromis niloticus). Three hundreds of tilapia (56.21 ± 0.81 g) were divided into 5 groups and fed a diet supplemented with C. butyricum at 0, 1 x 10⁴, 1 x 10⁵, 1 x 10⁶ or 1 x 10⁷ CFU g^-1 diet (denoted as CG, CB1, CB2, CB3 and CB4, respectively) for 56 days. Then 45 fish from each group were intraperitoneally injected with Streptococcus agalactiae, and the mortality was recorded for 14 days. The results showed that dietary C. butyricum significantly improved the specific growth rate (SGR) and feed intake in the CB2 group and decreased the cumulative mortality post-challenge with S. agalactiae in the CB2, CB3 and CB4 groups. The serum total antioxidant capacity and intestinal interleukin receptor-associated kinase-4 gene expression were significantly increased, and serum malondialdehyde content and diamine oxidase activity were significantly decreased in the CB1, CB2, CB3 and CB4 groups. Serum complement 3 and complement 4 concentrations and intestinal gene expression of tumour necrosis factor α, interleukin 8, and myeloid differentiation factor 88 were significantly higher in the CB2, CB3 and CB4 groups. Intestinal toll-like receptor 2 gene expression was significantly upregulated in the CB3 and CB4 groups. Dietary C. butyricum increased the diversity of the intestinal microbiota and the relative abundance of beneficial bacteria (such as Bacillus), and decreased the relative abundance of opportunistic pathogenic bacteria (such as Aeromonas) in the CB2 group. These results revealed that dietary C. butyricum at a suitable dose enhanced growth performance, elevated humoral and intestinal immunity, regulated the intestinal microbial components, and improved disease resistance in tilapia. The optimal dose was 1 x 10⁵ CFU g^-1 diet.

Potential of myricetin to restore the immune balance in dextran sulfate sodium-induced acute murine ulcerative colitis

OBJECTIVES

Myricetin is a bioactive compound in many edible plants with anti-inflammatory and anticarcinogenic activity. The current study aimed to determine the protective effects and mechanism of myricetin against ulcerative colitis (UC).

METHODS

Myricetin was orally administered at doses of 40 and 80 mg/kg to C57BL/6 mice with UC induced using dextran sulfate sodium. The disease-associated index and colon length were determined at the end of the experiment, the proportion of Treg, Th1 and Th17 was analysed by cytometry, and cytokines were detected using ELISA.

KEY FINDINGS

Myricetin (80 mg/kg) ameliorated the severity of inflammation in acute UC and significantly improved the condition. Myricetin (80 mg/kg) elevated the levels of IL-10 and transforming growth factor β. In addition, the proportion of regulatory T cells significantly increased in mice in the myricetin treatment group.

CONCLUSIONS

Taking together, these results suggest that myricetin exhibits significant protective effects against UC and it could be used as a potential treatment for UC.

The Effect of Clostridium butyricum on Gut Microbiota, Immune Response and Intestinal Barrier Function During the Development of Necrotic Enteritis in Chickens

Necrotic enteritis (NE) causes huge economic losses to the poultry industry. Probiotics are used as potential alternatives to antibiotics to prevent NE. It is known that Clostridium butyricum can act as a probiotic that can prevent infection. However, whether or not it exerts a beneficial effect on NE in chickens remains elusive. Therefore, we investigated the impact of C. butyricum on immune response and intestinal microbiota during the development of NE in chickens, including experimental stages with basal diets, high-fishmeal-supplementation diets, and Clostridium perfringens challenge. Chickens were divided into two groups from day 1 to day 20: one group had its diet supplemented with C. butyricum supplementation and one did not. At day 20, the chickens were divided into four groups: C. perfringens challenged and unchallenged chickens with and without C. butyricum supplementation. All groups were fed a basal diet for 13 days and thereafter a basal diet with 50% fishmeal from day 14 to 24. Chickens were infected with C. perfringens from day 21 to 23. At days 13, 20 and 24, samples were collected for analysis of the relative expression of immune response and intestinal mucosa barrier-related genes and intestinal microbes. The results show that C. butyricum can inhibit the increase in IL-17A gene expression and the reduction in Claudin-1 gene induced-expression caused by C. perfringens challenge. Moreover, C. butyricum was found to increase the expression of anti-inflammatory IL-10 in infected chickens. Although C. butyricum was found to have a significant beneficial effect on the structure of intestinal bacteria in the basal diet groups and decrease the abundance of C. perfringens in the gut, it did not significantly affect the occurrence of intestinal lesions and did not significantly correct the shift in gut bacterial composition post C. perfringens infection. In conclusion, although C. butyricum promotes the expression of anti-inflammatory and tight junction protein genes and inhibits pro-inflammatory genes in C. perfringens-challenged chickens, it is not adequate to improve the structure of intestinal microbiota in NE chickens. Therefore, more effective schemes of C. butyricum supplementation to prevent and treat NE in chickens need to be identified.

Mechanism of gut butyric acid producing bacteria for prevention and treatment of inflammatory bowel disease

Inflammatory bowel disease (IBD) represents a group of intestinal disorders with uncontrolled and chronic inflammation which include Crohn¡¯s disease (CD) and ulcerative colitis (UC). The incidence of IBD is increasing dramatically in Asian countries, especially in China. Recent studies have observed changes in the amount and structure of the gut butyrate-producing bacteria in IBD patients, which suggested that butyrate-producing bacteria might be related to the occurrence and development of IBD. This review will focus on the anti-inflammatory effects of butyrate-producing bacteria by producing butyric acid and butyrate and inhibiting inflammation as well as the immune characteristics of three species of butyrate-producing bacteria: Roseburia intestinalis, Faecalibacterium prausnitzii, and Clostridium butyricum. These mechanisms provide some new ideas and clues for IBD prevention and treatment.

Roseburia intestinalis inhibits oncostatin M and maintains tight junction integrity in a murine model of acute experimental colitis

Objective: Levels of oncostatin M (OSM) and the composition of gut microbiota predict responses to anti-TNF agents used for IBD therapy. Here, the aim was to investigate the effects of Roseburia intestinalis, a gut microbiota, on OSM and on intestinal barrier in colitis. Methods: In the murine model of 3% dextran sulfate sodium (DSS)-induced colitis, we tested disease activity index (DAI), colon length, histological score and expression of tight junction (TJ) proteins (ZO-1, occludin and claudin-1), OSM, TNF-α and TLR5. In addition, a cellular model was used to examine the role of R. intestinalis during secretion of OSM by lipopolysaccharide (LPS)-induced bone marrow-derived macrophages (BMDMs) isolated from wild-type (WT) and TLR5 knockout (TLR5 KO) mice. Furthermore, we evaluated the impact of OSM on expressions of TJ proteins by Caco-2 cells. Results: R. intestinalis in DSS-induced colitis decreased DAI score (p < .001), colon length shortening (6.46 ± 0.36 cm vs 5.65 ± 0.47 cm, p = .022), histological score (2.667 ± 1.15 vs 5.33 ± 1.14, p = .018) and increased expression of TJ proteins (p < .05). In addition, R. intestinalis reduced expression of OSM (p < .05) and TNF-α (p < .05), while increasing expression of TLR5 (p < .05). Furthermore, R. intestinalis reduced secretion of OSM (p < .05) by LPS-induced BMDMs isolated from WT and TLR5 KO mice. Moreover, OSM downregulated expression of TJ proteins (p < .05) by Caco-2 cells in a concentration-dependent manner. Conclusions: These results indicate that R. intestinalis attenuates inflammation in IBD by decreasing secretion of OSM and by promoting intestinal barrier function. Taken together, the data provide insight into the role of the gut microbiota in patients with IBD who are resistant to anti-TNF therapy.