Background:Inflammatory bowel disease(IBD)is a chronic inflammatory disease of the gastrointestinal tract.The destruction of the intestinal epithelial barrier is one of the major pathological processes in IBD patholog...Background:Inflammatory bowel disease(IBD)is a chronic inflammatory disease of the gastrointestinal tract.The destruction of the intestinal epithelial barrier is one of the major pathological processes in IBD pathology.Growing evidence indicated that epithelial cell ferroptosis is linked to IBD and is considered a target process.Methods:RAS-selective lethal 3(RSL3)was used to induce ferroptosis in intestinal epithelial cell line No.6(IEC-6)cells,and cell ferroptosis and the effects of tanshinone IIA(Tan IIA)were determined by cell counting kit-8(CCK-8),reactive oxygen species(ROS)staining,Giemsa staining and transmission electron microscope(TEM).The cell viability of natural product library compounds was determined by CCK-8.The expression of ferroptosis-related genes were detected by real-time quantitative polymerase chain reaction(RT-qPCR)and western blot.Results:Treatment of IEC-6 cells results in the accumulation of ROS and typical morphological characteristics of ferroptosis.RSL3 treatment caused rapid cellular cytotoxicity which could be reversed by ferrostatin-1(Fer-1)in IEC-6 cells.Natural product library screening revealed that Tan IIA is a potent inhibitor of IEC-6 cell ferroptosis.Tan IIA could significantly protect the RSL3-induced ferroptosis of IEC-6 cells.Furthermore,the ferroptosis suppressors,glutathione peroxidase 4(GPX4),solute carrier family 7 member 11(SLC7A11),and miR-17-92 were found to be early response genes in RSL3-treated cells.Treatment of IEC-6 cells with Tan IIA resulted in upregulation of GPX4,SLC7A11,and miR-17-92.Conclusion:Our study demonstrated that Tan IIA protects IEC-6 cells from ferroptosis through the upregulation of GPX4,SLC7A11,and miR-17-92.The findings might provide a theoretical grounding for the future application of Tan IIA to treat or prevent IBD.展开更多
The pathogenesis of inflammatory bowel diseases (IBDs) seems to involve a primary defect in one or more of the elements responsible for the maintenance of intestinal homeostasis and oral tolerance. The most important ...The pathogenesis of inflammatory bowel diseases (IBDs) seems to involve a primary defect in one or more of the elements responsible for the maintenance of intestinal homeostasis and oral tolerance. The most important element is represented by the intestinal barrier, a complex system formed mostly by intestinal epithelial cells (IECs). IECs have an active role in producing mucus and regulating its composition; they provide a physical barrier capable of controlling antigen traff ic through the intestinal mucosa. At the same time, they are able to play the role of non-professional antigen presenting cells, by processing and presenting antigens directly to the cells of the intestinal immune system. On the other hand, immune cells regulate epithelial growth and differentiation, producing a continuous bi-directional cross-talk within the barrier. Several alterations of the barrier function have been identif ied in IBD, starting from mucus features up to its components, from epithelial junctions up to the Toll-like receptors, and altered immune responses. It remains to be understood whether these defects are primary causes of epithelial damage or secondary effects. We review the possible role of the epithelial barrier and particularly describe the role of IECs in the pathogenesis of IBD.展开更多
BACKGROUND Recent studies have demonstrated that dysfunction of the intestinal barrier is a significant contributing factor to the development of severe acute pancreatitis(SAP).A stable intestinal mucosa barrier funct...BACKGROUND Recent studies have demonstrated that dysfunction of the intestinal barrier is a significant contributing factor to the development of severe acute pancreatitis(SAP).A stable intestinal mucosa barrier functions as a major anatomic and functional barrier,owing to the balance between intestinal epithelial cell(IEC)proliferation and apoptosis.There is some evidence that calcium overload may trigger IEC apoptosis and that calcineurin(CaN)/nuclear factor of activated Tcells(NFAT)signaling might play an important role in calcium-mediated apoptosis.AIM To investigate the potential mechanisms underlying the therapeutic effect of Qingyi decoction(QYD)in SAP.METHODS A rat model of SAP was created via retrograde infusion of sodium deoxycholate.Serum levels of amylase,tumor necrosis factor(TNF-α),interleukin(IL)-6,D-lactic acid,and diamine oxidase(DAO);histological changes;and apoptosis of IECs were examined in rats with or without QYD treatment.The expression of the two subunits of CaN and NFAT in intestinal tissue was measured via quantitative realtime polymerase chain reaction and western blotting.For in vitro studies,Caco-2 cells were treated with lipopolysaccharide(LPS)and QYD serum,and then cell viability and intracellular calcium levels were detected.RESULTS Retrograde infusion of sodium deoxycholate increased the severity of pancreatic and intestinal pathology and the levels of serum amylase,TNF-α,and IL-6.Both the indicators of intestinal mucosa damage(D-lactic acid and DAO)and the levels of IEC apoptosis were elevated in the SAP group.QYD treatment reduced the serum levels of amylase,TNF-α,IL-6,D-lactic acid,and DAO and attenuated the histological findings.IEC apoptosis associated with SAP was ameliorated under QYD treatment.In addition,the protein expression levels of the two subunits of CaN were remarkably elevated in the SAP group,and the NFATc3 gene was significantly upregulated at both the transcript and protein levels in the SAP group compared with the control group.QYD significantly restrained CaN and NFATc3 gene expression in the intestine,which was upregulated in the SAP group.Furthermore,QYD serum significantly decreased the LPS-induced elevation in intracellular free Ca^(2+)levels and inhibited cell death.CONCLUSION QYD can exert protective effects against intestinal mucosa damage caused by SAP and the protective effects are mediated,at least partially,by restraining IEC apoptosis via the CaN/NFATc3 pathway.展开更多
BACKGROUND Conventional Crohn’s disease(CD)treatments are supportive rather than curative and have serious side effects.Adipose-derived mesenchymal stem cells(ADSCs)have been gradually applied to treat various diseas...BACKGROUND Conventional Crohn’s disease(CD)treatments are supportive rather than curative and have serious side effects.Adipose-derived mesenchymal stem cells(ADSCs)have been gradually applied to treat various diseases.The therapeutic effect and underlying mechanism of ADSCs on CD are still not clear.AIM To investigate the effect of ADSC administration on CD and explore the potential mechanisms.METHODS Wistar rats were administered with 2,4,6-trinitrobenzene sulfonic acid(TNBS)to establish a rat model of CD,followed by tail injections of green fluorescent protein(GFP)-modified ADSCs.Flow cytometry,qRT-PCR,and Western blot were used to detect changes in the Wnt signaling pathway,T cell subtypes,and their related cytokines.RESULTS The isolated cells showed the characteristics of ADSCs,including spindle-shaped morphology,high expression of CD29,CD44,and CD90,low expression of CD34 and CD45,and osteogenic/adipogenic ability.ADSC therapy markedly reduced disease activity index and ameliorated colitis severity in the TNBS-induced rat model of CD.Furthermore,serum anti-sacchromyces cerevisiae antibody and panti-neutrophil cytoplasmic antibody levels were significantly reduced in ADSCtreated rats.Mechanistically,the GFP-ADSCs were colocalized with intestinal epithelial cells(IECs)in the CD rat model.GFP-ADSC delivery significantly antagonized TNBS-induced increased canonical Wnt pathway expression,decreased noncanonical Wnt signaling pathway expression,and increased apoptosis rates and protein level of cleaved caspase-3 in rats.In addition,ADSCs attenuated TNBS-induced abnormal inflammatory cytokine production,disturbed T cell subtypes,and their related markers in rats.CONCLUSION Successfully isolated ADSCs show therapeutic effects in CD by regulating IEC proliferation,the Wnt signaling pathway,and T cell immunity.展开更多
AIM To investigate toll-like receptor 2(TLR2) and TLR4 expression, following bifidobacteria and low-dose EPEC endotoxin treatment, and intestinal barrier function in rat intestinal epithelial cell-18(IEC-18).METHODS S...AIM To investigate toll-like receptor 2(TLR2) and TLR4 expression, following bifidobacteria and low-dose EPEC endotoxin treatment, and intestinal barrier function in rat intestinal epithelial cell-18(IEC-18).METHODS Six experimental groups were established-normal control, EPEC, Bifidobacteria infantis(B. infantis), B. longum, B. bifidum, and B. youth groups. Optimal EPEC endotoxin concentration, bifidobacteria fold dilution, and treatment duration were determined. Quantitative real-time polymerase chain reaction and western blot, respectively, were conducted to detect TLR2 and TLR4 m RNA and protein expression in IEC-18 cells. Transepithelial electrical resistance(TEER) was measured by the EVOM chopstick voltohmmeter in each group. All experiments were conducted in triplicate and data were analyzed on SPSS 16.RESULTS TLR2 and TLR4 m RNA and protein expression in the EPEC group were significantly higher than in the control group(P < 0.05). TLR2 m RNA and protein expression in the B. infantis, B. longum and B. youth groups were significantly lower than in the normal control group(P < 0.05). TLR4 m RNA and protein expression in the B. bifidum and B. youth groups were significantly lower than in normal controls(P < 0.05). In addition, the TEER in B. infantis, B. longum, B. bifidum, and B. youth groups were decreased by 19%, 18%, 23% and 23%, respectively, after 120 min of intervention, as compared to the control group. However, the TEER in the EPEC group was significantly decreased by 67% in comparison to the normal control group(P < 0.05).CONCLUSION Bifidobacteria protect IEC-18 cells against injury by down-regulating TLR2 and TLR4 expression and enhance intestinal barrier function to protect the intestinal epithelial cells from pathogenic invasion.展开更多
CDC42 controls intestinal epithelial(IEC)stem cell(IESC)division.How aberrant CDC42 initiates intestinal inflammation or neoplasia is unclear.We utilized models of inflam-matory bowel diseases(IBD),colorectal cancer,a...CDC42 controls intestinal epithelial(IEC)stem cell(IESC)division.How aberrant CDC42 initiates intestinal inflammation or neoplasia is unclear.We utilized models of inflam-matory bowel diseases(IBD),colorectal cancer,aging,and IESC injury to determine the loss of intestinal Cdc42 upon inflammation and neoplasia.Intestinal specimens were collected to determine the levels of CDC42 in IBD or colorectal cancer.Cdc42 floxed mice were crossed with Villin-Cre,Villin-CreERT2 and/or Lgr5-eGFP-IRES-CreERT2,or Bmi1-CreERT2 mice to generate Cdc42 deficient mice.Irradiation,colitis,aging,and intestinal organoid were used to evaluate CDC42 upon mucosal inflammation,IESC/progenitor regenerative capacity,and IEC repair.Our studies revealed that increased CDC42 in colorectal cancer correlated with lower survival;in contrast,lower levels of CDC42 were found in the inflamed IBD colon.Colonic Cdc42 depletion significantly reduced Lgr5+IEsCs,increased progenitors'hyperplasia,and induced mucosal inflammation,which led to crypt dysplasia.Colonic Cdc42 depletion markedly enhanced irra-diation-or chemical-induced colitis.Depletion or inhibition of Cdc42 reduced colonic Lgr5+IESC regeneration.In conclusion,depletion of Cdc42 reduces the IESC regeneration and IEC repair,leading to prolonged mucosal inflammation.Constitutive monogenic loss of Cdc42 in-duces mucosal inflammation,which could result in intestinal neoplasia in the context of aging.展开更多
Deubiquitinates(DUBs) alter the stabilities, localizations or activities of substrates by removing their ubiquitin conjugates,which are closely related to the development of inflammatory response. Here, we show that u...Deubiquitinates(DUBs) alter the stabilities, localizations or activities of substrates by removing their ubiquitin conjugates,which are closely related to the development of inflammatory response. Here, we show that ubiquitin-specific protease 47(USP47) prevents inflammation development in inflammatory bowel disease(IBD). Compared with wild-type mice, Usp47 knockout mice are more susceptible to dextran sodium sulfate(DSS)-induced acute and chronic colitis with higher inflammatory cytokines expression and severe intestinal tissue damage. Chimeric mouse experiments suggest that non-hematopoietic cells mainly contribute to the phenotype. And, DSS-induced colitis of the Usp47 knockout mice depends on commensal bacteria.Mechanistically, down-regulation of USP47 aggravates the activation of NF-κB signaling pathway by increasing the K63-linked poly-ubiquitination of tumor necrosis factor receptor-associated factor 6(TRAF6) in intestinal epithelial cells. Furthermore, the expression of USP47, negatively correlated with the degree of inflammation, is lower at colonic inflammatory lesions than that non-inflammatory sites from the intestine from ulcerative colitis(UC) and Crohn's disease(CD) patients. These data, taken together, indicate that USP47 regulates intestinal inflammation through de-ubiquitination of K63-linked poly-ubiquitination TRAF6 in intestinal epithelial cells.展开更多
Bacillus anthracis lethal toxin(LT)is a determinant of lethal anthrax.Its function in myeloid cells is required for bacterial dissemination,and LT itself can directly trigger dysfunction of the cardiovascular system.T...Bacillus anthracis lethal toxin(LT)is a determinant of lethal anthrax.Its function in myeloid cells is required for bacterial dissemination,and LT itself can directly trigger dysfunction of the cardiovascular system.The interplay between LT and the host responses is important in the pathogenesis,but our knowledge on this interplay remains limited.Tumor necrosis factor-a(TNF-a)is a pleiotropic pro-inflammatory cytokine induced by bacterial infections.Since LT accumulates and cytokines,predominantly TNF,amass during B.anthracis infection,co-treatment of TNF+LT in mice was used to mimic in vivo conditions for LT to function in inflamed hosts.Bone marrow transplantation and genetically engineered mice showed unexpectedly that the death of intestinal epithelial cells(IECs)rather than that of hematopoietic cells led to LT+TNF-induced lethality.Inhibition of p38a mitogen-activated protein kinase(MAPK)signaling by LT in IECs promoted TNF-induced apoptosis and necroptosis of IECs,leading to intestinal damage and mouse death.Consistently,p38a inhibition by LT enhanced TNF-mediated cell death in human colon epithelial HT-29 cells.As intestinal damage is one of the leading causes of lethality in anthrax patients,the IEC damage caused by LT+TNF would most likely be a mechanism underneath this clinical manifestation and could be a target for interventions.展开更多
Objective To investigate the effect of Chang’an Ⅱ Decoction(肠安Ⅱ号方))-containing serum on intestinal epithelial barrier dysfunction in rats.Methods Tumor necrosis factor(TNF)-α-induced injury of Caco-2 monolayer...Objective To investigate the effect of Chang’an Ⅱ Decoction(肠安Ⅱ号方))-containing serum on intestinal epithelial barrier dysfunction in rats.Methods Tumor necrosis factor(TNF)-α-induced injury of Caco-2 monolayers were established as an inflammatory model of human intestinal epithelium.Caco-2 monolayers were treated with blank serum and Chang’an Ⅱ Decoction-containing serum that obtained from the rats which were treated with distilled water and Chang’an Ⅱ Decoction intragastrically at doses of 0.49,0.98,1.96 g/(kg·d)for 1 week,respectively.After preparation of containing serum,cells were divided into the normal group,the model group,the Chang’an Ⅱ-H,M,and L groups(treated with 30 ng/mL TNF-αand medium plus 10%high,middle-,and low-doses Chang’an Ⅱ serum,respectively).Epithelial barrier function was assessed by transepithelial electrical resistance(TER)and permeability of fluorescein isothiocyanate(FITC)-labeled dextran.Transmission electron microscopy was used to observe the ultrastructure of tight junctions(TJs).Immunofluorescence of zonula occludens-1(ZO-1),claudin-1 and nuclear transcription factor-kappa p65(NF-κBp65)were measured to determine the protein distribution.The mRNA expression of myosin light chain kinase(MLCK)was measured by real-time polymerase chain reaction.The expression levels of MLCK,myosin light chain(MLC)and p-MLC were determined by Western blot.Results Chang’an Ⅱ Decoction-containing serum significantly attenuated the TER and paracellular permeability induced by TNF-α.It alleviated TNF-α-induced morphological alterations in TJ proteins.The increases in MLCK mRNA and MLCK,MLC and p-MLC protein expressions induced by TNF-αwere significantly inhibited in the Chang’an Ⅱ-H group.Additionally,Chang’an Ⅱ Decoction significantly attenuated translocation of NF-κBp65 into the nucleus.Conclusion High-dose Chang’an Ⅱ-containing serum attenuates TNF-α-induced intestinal barrier dysfunction.The underlying mechanism may be involved in inhibiting the MLCK-MLC phosphorylation signaling pathway mediated by NF-κBp65.展开更多
Dioscorea batatas Decne(DBD)has been used to heal various illnesses of the kidney and intestine as an herbal medicine in Asia.As a source of therapeutic agents,many glycoproteins have been isolated from mushrooms and ...Dioscorea batatas Decne(DBD)has been used to heal various illnesses of the kidney and intestine as an herbal medicine in Asia.As a source of therapeutic agents,many glycoproteins have been isolated from mushrooms and plants,but the functional role of glycoprotein in intestinal epithelial wound healing has not been understood yet.In the present study,we investigated the wound healing potentials of the 30 kDa glycoprotein(DBD glycoprotein)isolated from DBD in human intestinal epithelial(INT-407)cells.We found that DBD glycoprotein(100μg·mL^-1)significantly increased the motility of INT-407 cells for 24 h by activating protein kinase C(PKC).DBD glycoprotein stimulated the activation of p38 mitogen-activated protein kinase(MAPK),which is responsible for the phosphorylation of NF-κB inhibitorα(IκBα).DBD glycoprotein increased the level of profilin-1(PFN1),α-actinin and F-actin expression via activation of transcription factor,nuclear factor-kappa B(NF-κB)during its promotion of cell migration.Experimental mouse colitis was induced by adding dextran sulfate sodium(DSS)to the drinking water at a concentration of 4%(W/V)for 7 days.We figured out that administration of DBD glycoprotein(10 and 20 mg·kg-1)lowers the levels of disease activity index and histological inflammation in DSS-treated ICR mice.In this regard,we suggest that DBD glycoprotein has ability to promote the F-actin-related migration signaling events via activation of PKC and NF-κB in intestinal epithelial cells and prevent inflammatory bowel disease.展开更多
[Objective]This study was conducted to investigate the mechanism of Echinacea polysaccharide(EPS) in treatment of various bacterial infection and reduction of inflammation,so as to provide a theoretical basis for clin...[Objective]This study was conducted to investigate the mechanism of Echinacea polysaccharide(EPS) in treatment of various bacterial infection and reduction of inflammation,so as to provide a theoretical basis for clinic application of EPS.[Method]Nuclear protein extracted from six groups,the normal control group,the simple lipopolysaccharide(LPS) group and the EPS(with concentrations of 50,100,200 and 500 μg/ml,respectively) + LPS groups was subjected to SDS-PAGE electrophoresis,and pIkB-α protein contents in the extracts were analyzed by Coomassie brilliant blue(CBB) staining and Western-Blot method.[Result]The simple LPS group showed the highest pIkB-α protein level,and in the EPS concentration range of 0-200 μg/ml,the expression level of pIkB-α protein was improved with the increase of EPS concentration.[Conclusion]The expression level of pIkB-α protein was improved under the simulation of IEC-6 by LPS,while EPS could effectively inhibit the expression of pIkB-α protein.The expression level of pIkB-α was the lowest in the LPS +500 μg/ml EPS group.展开更多
Intestinal epithelial homeostasis plays an important role in intestinal morphology and function.However,the developmental changes in intestinal epithelial cell turnover in piglets during early weaning are unknown so f...Intestinal epithelial homeostasis plays an important role in intestinal morphology and function.However,the developmental changes in intestinal epithelial cell turnover in piglets during early weaning are unknown so far.Thus,the aim of this work was to detect changes in piglet gut development from weaning to post-weaning d 14.Accordingly,40 piglets were used in the present study,and 8 piglets were randomly selected for sampling at d 0,1,3,7 and 14 post-weaning,respectively.The results showed that weaning stress significantly affected small intestinal morphological architecture,and this impact was the worst on d 3,and then returned to normal on d 14.Furthermore,the number of the marker of proliferation Ki-67(Ki67)positive cells was decreased on d 1 and 3,and then recovered on d 14(P<0.001).Also,weaning strikingly increased jejunal epithelial cell shedding on d 1 to 7 compared on d 0(P<0.05).Moreover,weaning remarkably affected the number of small intestinal enterocytes,goblets and endocrine cells(P<0.05),and there were also significant differences in genes expression related to proliferation and differentiation(P<0.05).Additionally,the mechanistic target of rapamycin(mTOR)phosphorylation level was higher on d 3(P<0.05).However,the Wingless/Int1(WNT)/b-catenin pathway was not influenced by post-weaning days.Taken together,weaning induced noteworthy changes in intestinal epithelial cell proliferation,differentiation and shedding,and the mTOR signaling pathway was involved in this process.Our findings provide a cellular mechanism for intestinal developmental changes during weaning periods.This may provide nutritionists with better insight into designing efficient in-feed alternatives for preventing the unfavorable gut development in weaning piglets.展开更多
The gut microbiota plays a key role in host health and disease,particularly through their interactions with the immune system.Intestinal homeostasis is dependent on the symbiotic relationships between the host and the...The gut microbiota plays a key role in host health and disease,particularly through their interactions with the immune system.Intestinal homeostasis is dependent on the symbiotic relationships between the host and the diverse gut microbiota,which is influenced by the highly co-evolved immune-microbiota interactions.The first step of the interaction between the host and the gut microbiota is the sensing of the gut microbes by the host immune system.In this review,we describe the cells of the host immune system and the proteins that sense the components and metabolites of the gut microbes.We further highlight the essential roles of pattern recognition receptors(PRRs),the G protein-coupled receptors(GPCRs),aryl hydrocarbon receptor(AHR)and the nuclear receptors expressed in the intestinal epithelial cells(IECs)and the intestine-resident immune cells.We also discuss the mechanisms by which the disruption of microbial sensing because of genetic or environmental factors causes human diseases such as the inflammatory bowel disease(IBD).展开更多
Mannose is a naturally occurring sugar widely consumed in the daily diet;however,mechanistic insights into how mannose metabolism affects intestinal inflammation remain lacking.Herein,we reported that mannose suppleme...Mannose is a naturally occurring sugar widely consumed in the daily diet;however,mechanistic insights into how mannose metabolism affects intestinal inflammation remain lacking.Herein,we reported that mannose supplementation ameliorated colitis development and promoted colitis recovery.Macrophage-secreted inflammatory cytokines,particularly TNF-α,induced pathological endoplasmic reticulum stress(ERS)in intestinal epithelial cells(IECs),which was prevented by mannose via normalization of protein N-glycosylation.By preserving epithelial integrity,mannose reduced the inflammatory activation of colonic macrophages.On the other hand,mannose directly suppressed macrophage TNF-αproduction translationally by reducing the glyceraldehyde 3-phosphate level,thus promoting GAPDH binding to TNF-αmRNA.Additionally,we found dysregulated mannose metabolism in the colonic mucosa of patients with inflammatory bowel disease.Finally,we revealed that activating PMM2 activity with epalrestat,a clinically approved drug for the treatment of diabetic neuropathy,elicited further sensitization to the therapeutic effect of mannose.Therefore,mannose metabolism prevents TNF-α-mediated pathogenic crosstalk between IECs and intestinal macrophages,thereby normalizing aberrant immunometabolism in the gut.展开更多
The latest guideline about ulcerative colitis(UC) clinical practice stresses that mucosal healing, rather than anti-inflammation, is the main target in UC clinical management. Current mucosal dysfunction mainly closel...The latest guideline about ulcerative colitis(UC) clinical practice stresses that mucosal healing, rather than anti-inflammation, is the main target in UC clinical management. Current mucosal dysfunction mainly closely relates to the endoscopic intestinal wall(mechanical barrier) injury with the imbalance between intestinal epithelial cells(IECs) regeneration and death, as well as tight junction(TJ) dysfunction. It is suggested that biological barrier(gut microbiota), chemical barrier(mucus protein layer, MUC) and immune barrier(immune cells) all take part in the imbalance, leading to mechanical barrier injury. Lots of experimental studies reported that acupuncture and moxibustion on UC recovery by adjusting the gut microbiota, MUC and immune cells on multiple targets and pathways, which contributes to the balance of IEC regeneration and death, as well as TJ structure recovery in animals. Moreover, the validity and superiority of acupuncture and moxibustion were also demonstrated in clinic. This paper aims to review the achievements of acupuncture and moxibustion on mucosal healing and analyse the underlying mechanisms.展开更多
As the first line of defence against pathogens and endotoxins crossing the intestine-blood barrier,the intestinal epithelial barrier plays a determinant role in pigs’health and growth.4-Phenylbutyric acid(4-PBA),an a...As the first line of defence against pathogens and endotoxins crossing the intestine-blood barrier,the intestinal epithelial barrier plays a determinant role in pigs’health and growth.4-Phenylbutyric acid(4-PBA),an aromatic fatty acid,was reported to benefit homeostasis of endoplasmic reticulum and protein synthesis.However,whether 4-PBA affects intestinal epithelial barrier function in pigs is unknown.This study aimed to explore the effects of 4-PBA on the intestinal barrier function,using in vitro models of well-differentiated intestinal porcine epithelial cell(IPEC-J2)monolayers in the transwell plates.Cell monolayers with or without 4-PBA(1.0 mmol/L)treatment were challenged with physical scratch,deoxynivalenol(DON,2.0μg/mL,48 h),and lipopolysaccharide(LPS,5.0μg/mL,48 h),respectively.Transepithelial electrical resistance(TEER)and fluorescein isothiocyanate-dextran(FD-4)permeability were measured to indicate barrier integrity and permeability.Real-time PCR and Western blot were conducted to determine relative gene and protein expressions of tight junction proteins.As expected,physical scratch,DON,and LPS challenges decreased TEER and increased FD-4 permeability.4-PBA treatment accelerated cell mitigation and rehabilitation of the physical scratch-damaged intestinal epithelial barrier but did not alleviate DON or LPS induced barrier damage.However,once 48-h DON and LPS challenges were removed,rehabilitation of the epithelial barrier function of IPEC-J2 monolayer was accelerated by the 4-PBA treatment.Also,the relative gene and protein expressions of zonula occludens-1(ZO-1),occludin,and claudin-1 were further upregulated by the 4-PBA treatment during the barrier rehabilitation.Taken together,4-PBA accelerated the IPEC-J2 cell monolayer barrier recovering from physical scratch,DON-,and LPS-induced damage,via enhancing cell mitigation and expressions of tight junction proteins.展开更多
Deoxynivalenol(DON)is considered to be the most harmful mycotoxin that affects the intestinal health of animals and humans.Phenethyl isothiocyanate(PEITC)in feedstuff is an anti-nutritional factor and impairs nutrient...Deoxynivalenol(DON)is considered to be the most harmful mycotoxin that affects the intestinal health of animals and humans.Phenethyl isothiocyanate(PEITC)in feedstuff is an anti-nutritional factor and impairs nutrient digestion and absorption in the animal intestinal.In the current study,we aimed to explore the effects of PEITC on DON-induced apoptosis,intestinal tight junction disorder,and its potential molecular mechanism in the porcine jejunum epithelial cell line(IPEC-J2).Our results indicated that PEITC treatment markedly alleviated DON-induced cytotoxicity,decreasing the apoptotic cell percentage and pro-apoptotic mRNA/protein levels,and increasing zonula occludens-1(ZO-1),occludin and claudin-1 mRNA/protein expression.Meanwhile,PEITC treatment ameliorated DON-induced an increase of the inducible nitric oxide synthase(iNOS)and cyclooxygenase 2(COX-2)mRNA levels and intracellular reactive oxygen species(ROS)level,and a decrease of glutathione peroxidase 1(GPx1),superoxide dismutase 2(SOD2),catalase(CAT)and heme oxygenase 1(HO-1)mRNA levels.Additionally,PEITC treatment significantly down-regulated autophagy-related protein 5(ATG5),beclin-1 and microtubuleassociated protein 1 light chain 3B(LC3-II)mRNA/protein levels,decreased the number of green fluorescent protein-microtubule-associated protein 1 light-chain 3(GFP-LC3)puncta and phosphatidylinositol 3 kinase(PI3K)protein expression,and up-regulated phospho-protein kinase B(p-Akt)and phospho-mammalian target of rapamycin(p-mTOR)protein expression against DON.However,the activation of autophagy by rapamycin,an autophagy agonist,abolished the protective effects of PEITC against DON-induced cytotoxicity,apoptosis and intestinal tight junction disorder.Collectively,PEITC could confer protection against DON-induced porcine intestinal epithelial cell injury by suppressing ROSmediated autophagy.展开更多
基金supported by the National Key Research and Development Program(Grant Number:2017YFA0105303)the Natural Science Foundation of Shandong Province(Grant Number:ZR2020MH327).
文摘Background:Inflammatory bowel disease(IBD)is a chronic inflammatory disease of the gastrointestinal tract.The destruction of the intestinal epithelial barrier is one of the major pathological processes in IBD pathology.Growing evidence indicated that epithelial cell ferroptosis is linked to IBD and is considered a target process.Methods:RAS-selective lethal 3(RSL3)was used to induce ferroptosis in intestinal epithelial cell line No.6(IEC-6)cells,and cell ferroptosis and the effects of tanshinone IIA(Tan IIA)were determined by cell counting kit-8(CCK-8),reactive oxygen species(ROS)staining,Giemsa staining and transmission electron microscope(TEM).The cell viability of natural product library compounds was determined by CCK-8.The expression of ferroptosis-related genes were detected by real-time quantitative polymerase chain reaction(RT-qPCR)and western blot.Results:Treatment of IEC-6 cells results in the accumulation of ROS and typical morphological characteristics of ferroptosis.RSL3 treatment caused rapid cellular cytotoxicity which could be reversed by ferrostatin-1(Fer-1)in IEC-6 cells.Natural product library screening revealed that Tan IIA is a potent inhibitor of IEC-6 cell ferroptosis.Tan IIA could significantly protect the RSL3-induced ferroptosis of IEC-6 cells.Furthermore,the ferroptosis suppressors,glutathione peroxidase 4(GPX4),solute carrier family 7 member 11(SLC7A11),and miR-17-92 were found to be early response genes in RSL3-treated cells.Treatment of IEC-6 cells with Tan IIA resulted in upregulation of GPX4,SLC7A11,and miR-17-92.Conclusion:Our study demonstrated that Tan IIA protects IEC-6 cells from ferroptosis through the upregulation of GPX4,SLC7A11,and miR-17-92.The findings might provide a theoretical grounding for the future application of Tan IIA to treat or prevent IBD.
文摘The pathogenesis of inflammatory bowel diseases (IBDs) seems to involve a primary defect in one or more of the elements responsible for the maintenance of intestinal homeostasis and oral tolerance. The most important element is represented by the intestinal barrier, a complex system formed mostly by intestinal epithelial cells (IECs). IECs have an active role in producing mucus and regulating its composition; they provide a physical barrier capable of controlling antigen traff ic through the intestinal mucosa. At the same time, they are able to play the role of non-professional antigen presenting cells, by processing and presenting antigens directly to the cells of the intestinal immune system. On the other hand, immune cells regulate epithelial growth and differentiation, producing a continuous bi-directional cross-talk within the barrier. Several alterations of the barrier function have been identif ied in IBD, starting from mucus features up to its components, from epithelial junctions up to the Toll-like receptors, and altered immune responses. It remains to be understood whether these defects are primary causes of epithelial damage or secondary effects. We review the possible role of the epithelial barrier and particularly describe the role of IECs in the pathogenesis of IBD.
基金Supported by the National Key R and D Program of China,No.2019YFE0119300National Natural Science Foundation of China,No.82074158+2 种基金Project funded by China Postdoctoral Science Foundation,No.2018M631793Natural Science Foundation of Liaoning Province,No.2019-ZD-0624Dalian Traditional Chinese Medicine-Related Scientific Research Project,No.18Z2002.
文摘BACKGROUND Recent studies have demonstrated that dysfunction of the intestinal barrier is a significant contributing factor to the development of severe acute pancreatitis(SAP).A stable intestinal mucosa barrier functions as a major anatomic and functional barrier,owing to the balance between intestinal epithelial cell(IEC)proliferation and apoptosis.There is some evidence that calcium overload may trigger IEC apoptosis and that calcineurin(CaN)/nuclear factor of activated Tcells(NFAT)signaling might play an important role in calcium-mediated apoptosis.AIM To investigate the potential mechanisms underlying the therapeutic effect of Qingyi decoction(QYD)in SAP.METHODS A rat model of SAP was created via retrograde infusion of sodium deoxycholate.Serum levels of amylase,tumor necrosis factor(TNF-α),interleukin(IL)-6,D-lactic acid,and diamine oxidase(DAO);histological changes;and apoptosis of IECs were examined in rats with or without QYD treatment.The expression of the two subunits of CaN and NFAT in intestinal tissue was measured via quantitative realtime polymerase chain reaction and western blotting.For in vitro studies,Caco-2 cells were treated with lipopolysaccharide(LPS)and QYD serum,and then cell viability and intracellular calcium levels were detected.RESULTS Retrograde infusion of sodium deoxycholate increased the severity of pancreatic and intestinal pathology and the levels of serum amylase,TNF-α,and IL-6.Both the indicators of intestinal mucosa damage(D-lactic acid and DAO)and the levels of IEC apoptosis were elevated in the SAP group.QYD treatment reduced the serum levels of amylase,TNF-α,IL-6,D-lactic acid,and DAO and attenuated the histological findings.IEC apoptosis associated with SAP was ameliorated under QYD treatment.In addition,the protein expression levels of the two subunits of CaN were remarkably elevated in the SAP group,and the NFATc3 gene was significantly upregulated at both the transcript and protein levels in the SAP group compared with the control group.QYD significantly restrained CaN and NFATc3 gene expression in the intestine,which was upregulated in the SAP group.Furthermore,QYD serum significantly decreased the LPS-induced elevation in intracellular free Ca^(2+)levels and inhibited cell death.CONCLUSION QYD can exert protective effects against intestinal mucosa damage caused by SAP and the protective effects are mediated,at least partially,by restraining IEC apoptosis via the CaN/NFATc3 pathway.
基金National Natural Science Foundation of China,No.81770574,No.81600414,and No.81600447.
文摘BACKGROUND Conventional Crohn’s disease(CD)treatments are supportive rather than curative and have serious side effects.Adipose-derived mesenchymal stem cells(ADSCs)have been gradually applied to treat various diseases.The therapeutic effect and underlying mechanism of ADSCs on CD are still not clear.AIM To investigate the effect of ADSC administration on CD and explore the potential mechanisms.METHODS Wistar rats were administered with 2,4,6-trinitrobenzene sulfonic acid(TNBS)to establish a rat model of CD,followed by tail injections of green fluorescent protein(GFP)-modified ADSCs.Flow cytometry,qRT-PCR,and Western blot were used to detect changes in the Wnt signaling pathway,T cell subtypes,and their related cytokines.RESULTS The isolated cells showed the characteristics of ADSCs,including spindle-shaped morphology,high expression of CD29,CD44,and CD90,low expression of CD34 and CD45,and osteogenic/adipogenic ability.ADSC therapy markedly reduced disease activity index and ameliorated colitis severity in the TNBS-induced rat model of CD.Furthermore,serum anti-sacchromyces cerevisiae antibody and panti-neutrophil cytoplasmic antibody levels were significantly reduced in ADSCtreated rats.Mechanistically,the GFP-ADSCs were colocalized with intestinal epithelial cells(IECs)in the CD rat model.GFP-ADSC delivery significantly antagonized TNBS-induced increased canonical Wnt pathway expression,decreased noncanonical Wnt signaling pathway expression,and increased apoptosis rates and protein level of cleaved caspase-3 in rats.In addition,ADSCs attenuated TNBS-induced abnormal inflammatory cytokine production,disturbed T cell subtypes,and their related markers in rats.CONCLUSION Successfully isolated ADSCs show therapeutic effects in CD by regulating IEC proliferation,the Wnt signaling pathway,and T cell immunity.
基金Supported by Medjaden Academy and Research Foundation for Young Scientists,No.MJA20170410
文摘AIM To investigate toll-like receptor 2(TLR2) and TLR4 expression, following bifidobacteria and low-dose EPEC endotoxin treatment, and intestinal barrier function in rat intestinal epithelial cell-18(IEC-18).METHODS Six experimental groups were established-normal control, EPEC, Bifidobacteria infantis(B. infantis), B. longum, B. bifidum, and B. youth groups. Optimal EPEC endotoxin concentration, bifidobacteria fold dilution, and treatment duration were determined. Quantitative real-time polymerase chain reaction and western blot, respectively, were conducted to detect TLR2 and TLR4 m RNA and protein expression in IEC-18 cells. Transepithelial electrical resistance(TEER) was measured by the EVOM chopstick voltohmmeter in each group. All experiments were conducted in triplicate and data were analyzed on SPSS 16.RESULTS TLR2 and TLR4 m RNA and protein expression in the EPEC group were significantly higher than in the control group(P < 0.05). TLR2 m RNA and protein expression in the B. infantis, B. longum and B. youth groups were significantly lower than in the normal control group(P < 0.05). TLR4 m RNA and protein expression in the B. bifidum and B. youth groups were significantly lower than in normal controls(P < 0.05). In addition, the TEER in B. infantis, B. longum, B. bifidum, and B. youth groups were decreased by 19%, 18%, 23% and 23%, respectively, after 120 min of intervention, as compared to the control group. However, the TEER in the EPEC group was significantly decreased by 67% in comparison to the normal control group(P < 0.05).CONCLUSION Bifidobacteria protect IEC-18 cells against injury by down-regulating TLR2 and TLR4 expression and enhance intestinal barrier function to protect the intestinal epithelial cells from pathogenic invasion.
基金supported by NIDDK RO1,USA(No.R01DK123299)(X.H.)MHMC/CWRU start-up(X.H.).R.M.was supported by a private cancer metabolism grant donation from Liechtenstein and the Austrian Science Fund(FWF)(No.SFB F4707 and SFB-F06105).
文摘CDC42 controls intestinal epithelial(IEC)stem cell(IESC)division.How aberrant CDC42 initiates intestinal inflammation or neoplasia is unclear.We utilized models of inflam-matory bowel diseases(IBD),colorectal cancer,aging,and IESC injury to determine the loss of intestinal Cdc42 upon inflammation and neoplasia.Intestinal specimens were collected to determine the levels of CDC42 in IBD or colorectal cancer.Cdc42 floxed mice were crossed with Villin-Cre,Villin-CreERT2 and/or Lgr5-eGFP-IRES-CreERT2,or Bmi1-CreERT2 mice to generate Cdc42 deficient mice.Irradiation,colitis,aging,and intestinal organoid were used to evaluate CDC42 upon mucosal inflammation,IESC/progenitor regenerative capacity,and IEC repair.Our studies revealed that increased CDC42 in colorectal cancer correlated with lower survival;in contrast,lower levels of CDC42 were found in the inflamed IBD colon.Colonic Cdc42 depletion significantly reduced Lgr5+IEsCs,increased progenitors'hyperplasia,and induced mucosal inflammation,which led to crypt dysplasia.Colonic Cdc42 depletion markedly enhanced irra-diation-or chemical-induced colitis.Depletion or inhibition of Cdc42 reduced colonic Lgr5+IESC regeneration.In conclusion,depletion of Cdc42 reduces the IESC regeneration and IEC repair,leading to prolonged mucosal inflammation.Constitutive monogenic loss of Cdc42 in-duces mucosal inflammation,which could result in intestinal neoplasia in the context of aging.
基金supported in part by the National Key Research and Development Program of China (2017YFA0505202)the National Natural Science Foundation of China (81700475)the Shanghai Frontiers Science Center of Cellular Homeostasis and Human Diseases and the State Key Laboratory of Oncogenes and Related Genes (KF2107)。
文摘Deubiquitinates(DUBs) alter the stabilities, localizations or activities of substrates by removing their ubiquitin conjugates,which are closely related to the development of inflammatory response. Here, we show that ubiquitin-specific protease 47(USP47) prevents inflammation development in inflammatory bowel disease(IBD). Compared with wild-type mice, Usp47 knockout mice are more susceptible to dextran sodium sulfate(DSS)-induced acute and chronic colitis with higher inflammatory cytokines expression and severe intestinal tissue damage. Chimeric mouse experiments suggest that non-hematopoietic cells mainly contribute to the phenotype. And, DSS-induced colitis of the Usp47 knockout mice depends on commensal bacteria.Mechanistically, down-regulation of USP47 aggravates the activation of NF-κB signaling pathway by increasing the K63-linked poly-ubiquitination of tumor necrosis factor receptor-associated factor 6(TRAF6) in intestinal epithelial cells. Furthermore, the expression of USP47, negatively correlated with the degree of inflammation, is lower at colonic inflammatory lesions than that non-inflammatory sites from the intestine from ulcerative colitis(UC) and Crohn's disease(CD) patients. These data, taken together, indicate that USP47 regulates intestinal inflammation through de-ubiquitination of K63-linked poly-ubiquitination TRAF6 in intestinal epithelial cells.
基金supported by the National Natural Science Foundation of China (grant 82388201 to J.H.,grant 31701205 to P.Z.,grant 31801158 to Y.z.)the National Key R&D Program of China (2020YFA0803500 to J.H.)+2 种基金the CAMS Innovation Fund for Medical Sciences (CIFMS) (2019-I2M-5-062 to J.H.)the Fujian Province Central to Local Science and Technology Development Special Program (2022L3079 to J.H.)the Fu-Xia-Quan Zi-Chuang District Cooperation Program (3502ZCQXT2022003 to J.H.).
文摘Bacillus anthracis lethal toxin(LT)is a determinant of lethal anthrax.Its function in myeloid cells is required for bacterial dissemination,and LT itself can directly trigger dysfunction of the cardiovascular system.The interplay between LT and the host responses is important in the pathogenesis,but our knowledge on this interplay remains limited.Tumor necrosis factor-a(TNF-a)is a pleiotropic pro-inflammatory cytokine induced by bacterial infections.Since LT accumulates and cytokines,predominantly TNF,amass during B.anthracis infection,co-treatment of TNF+LT in mice was used to mimic in vivo conditions for LT to function in inflamed hosts.Bone marrow transplantation and genetically engineered mice showed unexpectedly that the death of intestinal epithelial cells(IECs)rather than that of hematopoietic cells led to LT+TNF-induced lethality.Inhibition of p38a mitogen-activated protein kinase(MAPK)signaling by LT in IECs promoted TNF-induced apoptosis and necroptosis of IECs,leading to intestinal damage and mouse death.Consistently,p38a inhibition by LT enhanced TNF-mediated cell death in human colon epithelial HT-29 cells.As intestinal damage is one of the leading causes of lethality in anthrax patients,the IEC damage caused by LT+TNF would most likely be a mechanism underneath this clinical manifestation and could be a target for interventions.
基金Supported by the National Nature Science Foundation of China(No.81373580,81173209,81704070)Visiting Scientist Program of China Academy of Chinese Medical Sciences(No.ZZ070801)"Ten Diseases and Ten Drugs"Program of Beijing Municipal Science and Technology Commission(No.Z161100000116046)。
文摘Objective To investigate the effect of Chang’an Ⅱ Decoction(肠安Ⅱ号方))-containing serum on intestinal epithelial barrier dysfunction in rats.Methods Tumor necrosis factor(TNF)-α-induced injury of Caco-2 monolayers were established as an inflammatory model of human intestinal epithelium.Caco-2 monolayers were treated with blank serum and Chang’an Ⅱ Decoction-containing serum that obtained from the rats which were treated with distilled water and Chang’an Ⅱ Decoction intragastrically at doses of 0.49,0.98,1.96 g/(kg·d)for 1 week,respectively.After preparation of containing serum,cells were divided into the normal group,the model group,the Chang’an Ⅱ-H,M,and L groups(treated with 30 ng/mL TNF-αand medium plus 10%high,middle-,and low-doses Chang’an Ⅱ serum,respectively).Epithelial barrier function was assessed by transepithelial electrical resistance(TER)and permeability of fluorescein isothiocyanate(FITC)-labeled dextran.Transmission electron microscopy was used to observe the ultrastructure of tight junctions(TJs).Immunofluorescence of zonula occludens-1(ZO-1),claudin-1 and nuclear transcription factor-kappa p65(NF-κBp65)were measured to determine the protein distribution.The mRNA expression of myosin light chain kinase(MLCK)was measured by real-time polymerase chain reaction.The expression levels of MLCK,myosin light chain(MLC)and p-MLC were determined by Western blot.Results Chang’an Ⅱ Decoction-containing serum significantly attenuated the TER and paracellular permeability induced by TNF-α.It alleviated TNF-α-induced morphological alterations in TJ proteins.The increases in MLCK mRNA and MLCK,MLC and p-MLC protein expressions induced by TNF-αwere significantly inhibited in the Chang’an Ⅱ-H group.Additionally,Chang’an Ⅱ Decoction significantly attenuated translocation of NF-κBp65 into the nucleus.Conclusion High-dose Chang’an Ⅱ-containing serum attenuates TNF-α-induced intestinal barrier dysfunction.The underlying mechanism may be involved in inhibiting the MLCK-MLC phosphorylation signaling pathway mediated by NF-κBp65.
基金Daegu Haany University Ky·lin Foundation in 2018。
文摘Dioscorea batatas Decne(DBD)has been used to heal various illnesses of the kidney and intestine as an herbal medicine in Asia.As a source of therapeutic agents,many glycoproteins have been isolated from mushrooms and plants,but the functional role of glycoprotein in intestinal epithelial wound healing has not been understood yet.In the present study,we investigated the wound healing potentials of the 30 kDa glycoprotein(DBD glycoprotein)isolated from DBD in human intestinal epithelial(INT-407)cells.We found that DBD glycoprotein(100μg·mL^-1)significantly increased the motility of INT-407 cells for 24 h by activating protein kinase C(PKC).DBD glycoprotein stimulated the activation of p38 mitogen-activated protein kinase(MAPK),which is responsible for the phosphorylation of NF-κB inhibitorα(IκBα).DBD glycoprotein increased the level of profilin-1(PFN1),α-actinin and F-actin expression via activation of transcription factor,nuclear factor-kappa B(NF-κB)during its promotion of cell migration.Experimental mouse colitis was induced by adding dextran sulfate sodium(DSS)to the drinking water at a concentration of 4%(W/V)for 7 days.We figured out that administration of DBD glycoprotein(10 and 20 mg·kg-1)lowers the levels of disease activity index and histological inflammation in DSS-treated ICR mice.In this regard,we suggest that DBD glycoprotein has ability to promote the F-actin-related migration signaling events via activation of PKC and NF-κB in intestinal epithelial cells and prevent inflammatory bowel disease.
基金Supported by Natural Science Foundation of China(31472230)Natural Science Foundation of Hebei Province(C2014407068)Fund from Science and Technology Department of Hebei Province(NO.14966610D)
文摘[Objective]This study was conducted to investigate the mechanism of Echinacea polysaccharide(EPS) in treatment of various bacterial infection and reduction of inflammation,so as to provide a theoretical basis for clinic application of EPS.[Method]Nuclear protein extracted from six groups,the normal control group,the simple lipopolysaccharide(LPS) group and the EPS(with concentrations of 50,100,200 and 500 μg/ml,respectively) + LPS groups was subjected to SDS-PAGE electrophoresis,and pIkB-α protein contents in the extracts were analyzed by Coomassie brilliant blue(CBB) staining and Western-Blot method.[Result]The simple LPS group showed the highest pIkB-α protein level,and in the EPS concentration range of 0-200 μg/ml,the expression level of pIkB-α protein was improved with the increase of EPS concentration.[Conclusion]The expression level of pIkB-α protein was improved under the simulation of IEC-6 by LPS,while EPS could effectively inhibit the expression of pIkB-α protein.The expression level of pIkB-α was the lowest in the LPS +500 μg/ml EPS group.
基金the Hunan Province’s Changsha-Zhuzhou-Xiangtan National Independent Innovation Demonstration Zone projects(Grant No.2017XK2058).
文摘Intestinal epithelial homeostasis plays an important role in intestinal morphology and function.However,the developmental changes in intestinal epithelial cell turnover in piglets during early weaning are unknown so far.Thus,the aim of this work was to detect changes in piglet gut development from weaning to post-weaning d 14.Accordingly,40 piglets were used in the present study,and 8 piglets were randomly selected for sampling at d 0,1,3,7 and 14 post-weaning,respectively.The results showed that weaning stress significantly affected small intestinal morphological architecture,and this impact was the worst on d 3,and then returned to normal on d 14.Furthermore,the number of the marker of proliferation Ki-67(Ki67)positive cells was decreased on d 1 and 3,and then recovered on d 14(P<0.001).Also,weaning strikingly increased jejunal epithelial cell shedding on d 1 to 7 compared on d 0(P<0.05).Moreover,weaning remarkably affected the number of small intestinal enterocytes,goblets and endocrine cells(P<0.05),and there were also significant differences in genes expression related to proliferation and differentiation(P<0.05).Additionally,the mechanistic target of rapamycin(mTOR)phosphorylation level was higher on d 3(P<0.05).However,the Wingless/Int1(WNT)/b-catenin pathway was not influenced by post-weaning days.Taken together,weaning induced noteworthy changes in intestinal epithelial cell proliferation,differentiation and shedding,and the mTOR signaling pathway was involved in this process.Our findings provide a cellular mechanism for intestinal developmental changes during weaning periods.This may provide nutritionists with better insight into designing efficient in-feed alternatives for preventing the unfavorable gut development in weaning piglets.
基金We would like to thank W.Tao,H.Ma,and other members of Zhu laboratory and Z.Wei in Richard Flavell’s lab for helpful discussions.This work was supported by grants from the National Key R&D Program of China(Grant No.2018YFA0508000,S.Z.)the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB29030101,S.Z.)+1 种基金the CAS Project for Young Scientists in Basic Research(Grant No.YSBR-074,S.Z.)the National Natural Science Foundation of China(Grant No.82061148013,S.Z.).
文摘The gut microbiota plays a key role in host health and disease,particularly through their interactions with the immune system.Intestinal homeostasis is dependent on the symbiotic relationships between the host and the diverse gut microbiota,which is influenced by the highly co-evolved immune-microbiota interactions.The first step of the interaction between the host and the gut microbiota is the sensing of the gut microbes by the host immune system.In this review,we describe the cells of the host immune system and the proteins that sense the components and metabolites of the gut microbes.We further highlight the essential roles of pattern recognition receptors(PRRs),the G protein-coupled receptors(GPCRs),aryl hydrocarbon receptor(AHR)and the nuclear receptors expressed in the intestinal epithelial cells(IECs)and the intestine-resident immune cells.We also discuss the mechanisms by which the disruption of microbial sensing because of genetic or environmental factors causes human diseases such as the inflammatory bowel disease(IBD).
基金supported by the National Natural Science Foundation of China(82271862 and 81873418 to YK,82171730 to PX,81970484 to QC)the Zhejiang Provincial Ten Thousand Program for Leading Talents of Science and Technology Innovation(2021R52015 to YK)the Natural Science Foundation of Zhejiang Province(LY20H160032 to PX,LQ21H090064 to TP).
文摘Mannose is a naturally occurring sugar widely consumed in the daily diet;however,mechanistic insights into how mannose metabolism affects intestinal inflammation remain lacking.Herein,we reported that mannose supplementation ameliorated colitis development and promoted colitis recovery.Macrophage-secreted inflammatory cytokines,particularly TNF-α,induced pathological endoplasmic reticulum stress(ERS)in intestinal epithelial cells(IECs),which was prevented by mannose via normalization of protein N-glycosylation.By preserving epithelial integrity,mannose reduced the inflammatory activation of colonic macrophages.On the other hand,mannose directly suppressed macrophage TNF-αproduction translationally by reducing the glyceraldehyde 3-phosphate level,thus promoting GAPDH binding to TNF-αmRNA.Additionally,we found dysregulated mannose metabolism in the colonic mucosa of patients with inflammatory bowel disease.Finally,we revealed that activating PMM2 activity with epalrestat,a clinically approved drug for the treatment of diabetic neuropathy,elicited further sensitization to the therapeutic effect of mannose.Therefore,mannose metabolism prevents TNF-α-mediated pathogenic crosstalk between IECs and intestinal macrophages,thereby normalizing aberrant immunometabolism in the gut.
基金Supported by National Key Research and Development Program of China(No.2019YFC1709002)National Natural Science Foundation of China(No.81973947 and 82004453)+4 种基金Natural Science Foundation of Nanjing University of Chinese Medicine(No.XZR2020043)Jiangsu Province Chinese Medicine Science and Technology Development Program(No.YB201951)Changzhou Science and Technology Program(No.CJ20190070)Changzhou Municipal Health Commission Science and Technology Program(No.QN 201939)Changzhou Municipal Health Qing Miao Talent Training Program(No.CZQM2020083)。
文摘The latest guideline about ulcerative colitis(UC) clinical practice stresses that mucosal healing, rather than anti-inflammation, is the main target in UC clinical management. Current mucosal dysfunction mainly closely relates to the endoscopic intestinal wall(mechanical barrier) injury with the imbalance between intestinal epithelial cells(IECs) regeneration and death, as well as tight junction(TJ) dysfunction. It is suggested that biological barrier(gut microbiota), chemical barrier(mucus protein layer, MUC) and immune barrier(immune cells) all take part in the imbalance, leading to mechanical barrier injury. Lots of experimental studies reported that acupuncture and moxibustion on UC recovery by adjusting the gut microbiota, MUC and immune cells on multiple targets and pathways, which contributes to the balance of IEC regeneration and death, as well as TJ structure recovery in animals. Moreover, the validity and superiority of acupuncture and moxibustion were also demonstrated in clinic. This paper aims to review the achievements of acupuncture and moxibustion on mucosal healing and analyse the underlying mechanisms.
基金funded by the“Shennong Scholar funding of Hunan Agricultural University”,the“Changsha Municipal Natural Science Foundation(Grant No.kq2014068)”the“Open Project Program of Key Laboratory of Feed Biotechnology,the Ministry of Agriculture and Rural Affairs of the People’s Republic of China”。
文摘As the first line of defence against pathogens and endotoxins crossing the intestine-blood barrier,the intestinal epithelial barrier plays a determinant role in pigs’health and growth.4-Phenylbutyric acid(4-PBA),an aromatic fatty acid,was reported to benefit homeostasis of endoplasmic reticulum and protein synthesis.However,whether 4-PBA affects intestinal epithelial barrier function in pigs is unknown.This study aimed to explore the effects of 4-PBA on the intestinal barrier function,using in vitro models of well-differentiated intestinal porcine epithelial cell(IPEC-J2)monolayers in the transwell plates.Cell monolayers with or without 4-PBA(1.0 mmol/L)treatment were challenged with physical scratch,deoxynivalenol(DON,2.0μg/mL,48 h),and lipopolysaccharide(LPS,5.0μg/mL,48 h),respectively.Transepithelial electrical resistance(TEER)and fluorescein isothiocyanate-dextran(FD-4)permeability were measured to indicate barrier integrity and permeability.Real-time PCR and Western blot were conducted to determine relative gene and protein expressions of tight junction proteins.As expected,physical scratch,DON,and LPS challenges decreased TEER and increased FD-4 permeability.4-PBA treatment accelerated cell mitigation and rehabilitation of the physical scratch-damaged intestinal epithelial barrier but did not alleviate DON or LPS induced barrier damage.However,once 48-h DON and LPS challenges were removed,rehabilitation of the epithelial barrier function of IPEC-J2 monolayer was accelerated by the 4-PBA treatment.Also,the relative gene and protein expressions of zonula occludens-1(ZO-1),occludin,and claudin-1 were further upregulated by the 4-PBA treatment during the barrier rehabilitation.Taken together,4-PBA accelerated the IPEC-J2 cell monolayer barrier recovering from physical scratch,DON-,and LPS-induced damage,via enhancing cell mitigation and expressions of tight junction proteins.
基金This study was financially supported by the National Natural Science Foundation of China(32072926,31772811)the Priority Academic Program Development of Jiangsu Higher Education Institutions(Jiangsu,China).
文摘Deoxynivalenol(DON)is considered to be the most harmful mycotoxin that affects the intestinal health of animals and humans.Phenethyl isothiocyanate(PEITC)in feedstuff is an anti-nutritional factor and impairs nutrient digestion and absorption in the animal intestinal.In the current study,we aimed to explore the effects of PEITC on DON-induced apoptosis,intestinal tight junction disorder,and its potential molecular mechanism in the porcine jejunum epithelial cell line(IPEC-J2).Our results indicated that PEITC treatment markedly alleviated DON-induced cytotoxicity,decreasing the apoptotic cell percentage and pro-apoptotic mRNA/protein levels,and increasing zonula occludens-1(ZO-1),occludin and claudin-1 mRNA/protein expression.Meanwhile,PEITC treatment ameliorated DON-induced an increase of the inducible nitric oxide synthase(iNOS)and cyclooxygenase 2(COX-2)mRNA levels and intracellular reactive oxygen species(ROS)level,and a decrease of glutathione peroxidase 1(GPx1),superoxide dismutase 2(SOD2),catalase(CAT)and heme oxygenase 1(HO-1)mRNA levels.Additionally,PEITC treatment significantly down-regulated autophagy-related protein 5(ATG5),beclin-1 and microtubuleassociated protein 1 light chain 3B(LC3-II)mRNA/protein levels,decreased the number of green fluorescent protein-microtubule-associated protein 1 light-chain 3(GFP-LC3)puncta and phosphatidylinositol 3 kinase(PI3K)protein expression,and up-regulated phospho-protein kinase B(p-Akt)and phospho-mammalian target of rapamycin(p-mTOR)protein expression against DON.However,the activation of autophagy by rapamycin,an autophagy agonist,abolished the protective effects of PEITC against DON-induced cytotoxicity,apoptosis and intestinal tight junction disorder.Collectively,PEITC could confer protection against DON-induced porcine intestinal epithelial cell injury by suppressing ROSmediated autophagy.
