Objective:To investigate the effect of synbiotic mulberry on kidney injury in a dextran sodium sulfate(DSS)-induced colitis model.Methods:Male Wistar rats were given drinking water containing 4%DSS for 7 days.Subseque...Objective:To investigate the effect of synbiotic mulberry on kidney injury in a dextran sodium sulfate(DSS)-induced colitis model.Methods:Male Wistar rats were given drinking water containing 4%DSS for 7 days.Subsequently,the rats were treated by oral gavage with synbiotic mulberry at 250,500,and 1000 mg/kg,sulfasalazine at 100 mg/kg,or synbiotic at 1000 mg/kg for an additional 7 days while receiving 0.4%DSS in drinking water.The severity of colitis was evaluated based on the disease activity index score.On day 14,plasma was collected,and the kidneys were harvested to evaluate kidney injury parameters and histological changes.In addition,the expression of genes associated with kidney injury was determined by quantitative RT-PCR.Results:Treatment with all doses of synbiotic mulberry significantly lowered the disease activity index score,accompanied by reductions in kidney histopathological changes,malondialdehyde concentration,and plasma cystatin C levels.Kidney fibrosis was also ameliorated by 500 and 1000 mg/kg of synbiotic mulberry.Treatment with 250 and 500 mg/kg of synbiotic mulberry downregulated IL-18 mRNA expression,while KIM-1 mRNA expression was reduced and plasma lipopolysaccharide-binding protein level was restored by 1000 mg/kg of synbiotic mulberry.Conclusions:Synbiotic mulberry ameliorates kidney injury in rats with DSS-induced colitis.It may be further explored as a treatment of kidney injury under colitis conditions.展开更多
Chondroitin sulfate(CS)is one of the main bioactive compounds in animal cartilage.In this study,the antiinflammatory activity of sturgeon-derived chondroitin sulfate(SCS)was evaluated in the dextran sulfate sodium(DSS...Chondroitin sulfate(CS)is one of the main bioactive compounds in animal cartilage.In this study,the antiinflammatory activity of sturgeon-derived chondroitin sulfate(SCS)was evaluated in the dextran sulfate sodium(DSS)-induced BALB/c mice model.Orally administration of SCS significantly alleviated the DSSinduced colitis symptoms,including the reduction of crypt depth,inhibition of the abnormal crypt foci formation,down-regulation of the proinflammatory biomarkers(NO,interleukin(IL)-6,IL-1βand tumor necrosis factor-α)and up-regulation of the anti-inflammatory biomarkers(IL-10 and IL-4).The gut microbiota analysis revealed that SCS alters the intestinal microbiota composition in colitis mice,especially the increase of the relative abundance of Ruminococcaceae and Lachnospiraceae.This alternation further induced primary bile acids convert into secondary bile acids.With SCS administration,the levels of deoxycholic acid(DCA)and litho cholic acid(LCA)were increased by 1.5-and 2.5-fold,respectively.The stimulated secretion of DCA and LCA showed further activation of the NF-κB signaling pathway,thereby suppressing the inflammatory response and attenuating inflammatory bowel disease(IBD)in mice.This study provided a valuable strategy for colitis prevention and treatment with sturgeon cartilage by-products.展开更多
Idiopathic pulmonary fibrosis(IPF)is a progressive and fatal interstitial lung disease characterized by excessive fibrotic remodeling,for which effective therapeutic options remain severely limited.Among the pathogeni...Idiopathic pulmonary fibrosis(IPF)is a progressive and fatal interstitial lung disease characterized by excessive fibrotic remodeling,for which effective therapeutic options remain severely limited.Among the pathogenic mechanisms implicated in IPF,epithelial-to-mesenchymal transition(EMT)is recognized as a pivotal driver of fibroblast activation and extracellular matrix deposition.In this study,we aimed to develop low-molecular-weight dextran sulfate sodium(LMW-DSS)derivatives and assess their capacity to interfere with EMT,thereby offering novel therapeutic avenues for IPF management.Starting with dextran(2 kDa)as a precursor,we successfully synthesized two sulfated derivatives,DSS-LS and DSS-HS,via distinct sulfonation processes.Using a TGF-β1-stimulated A549 alveolar epithelial cell model,we demonstrated that LMW-DSS compounds exhibited no cytotoxicity,as validated by CCK-8 viability assays.Importantly,Transwell migration assays revealed that LMW-DSS markedly attenuated TGF-β1-induced A549 cell migration,indicating a potent anti-fibrotic effect.Moreover,qPCR and Western blotting analyses confirmed that LMW-DSS significantly suppressed the expression and secretion of key pro-fibrotic mediators,including TGF-β1 and VEGF-A,and downregulated critical EMT-associated markers such as Snail and vimentin.Notably,reducedα-SMA expression following LMW-DSS treatment further substantiated its role in hindering EMT progression.Collectively,these findings highlighted the capacity of LMW-DSS to effectively impede EMT and fibrotic processes,thereby delaying the progression of pulmonary fibrosis.This work not only underscored the therapeutic potential of LMW-DSS in IPF but also provided compelling experimental evidence to support its development as a promising anti-fibrotic agent for clinical application.展开更多
Inflammatory bowel disease(IBD)is a complex relapsing inflammatory disease in the gut and is driven by complicated host-gut microbiome interactions.Gut commensals have shown different functions in IBD prevention and t...Inflammatory bowel disease(IBD)is a complex relapsing inflammatory disease in the gut and is driven by complicated host-gut microbiome interactions.Gut commensals have shown different functions in IBD prevention and treatment.To gain a mechanistic understanding of how different commensals affect intestinal inflammation,we compared the protective effects of 6 probiotics(belonging to the genera Akkermansia,Bifidobacterium,Clostridium,and Enterococcus)on dextran sulfate sodium(DSS)-induced colitis in mice with or without gut microbiota.Anti-inflammatory properties(ratio of interleukin(IL)-10 and IL-12)of these strains were also evaluated in an in vitro mesenteric lymph nodes(MLN)co-culture system.Results showed that 4 probiotics(belonging to the species Bifidobacterium breve,Bifidobacterium bifidum,and Enterococcus faecalis)can alleviate colitis in normal mice.The probiotic strains differed in regulating the intestinal microbiota,cytokines(IL-10,IL-1βand interferon(IFN)-γ),and tight junction function(Zonulin-1 and Occludin).By constrast,Akkermansia muciniphila AH39 and Clostridium butyricum FHuNHHMY49T1 were not protective.Interestingly,B.breve JSNJJNM2 with high anti-inflammatory potential in the MLN model could relieve colitis symptoms in antibiotic cocktail(Abx)-treated mice.Meanwhile,E.faecalis FJSWX25M1induced low levels of cytokines in vitro and showed no beneficial effects.Therefore,we provided insight into the clinical application of probiotics in IBD treatment.展开更多
BACKGROUND Ulcerative colitis is a chronic inflammatory disease of the colon with an unknown etiology.Alkaline sphingomyelinase(alk-SMase)is specifically expressed by intestinal epithelial cells,and has been reported ...BACKGROUND Ulcerative colitis is a chronic inflammatory disease of the colon with an unknown etiology.Alkaline sphingomyelinase(alk-SMase)is specifically expressed by intestinal epithelial cells,and has been reported to play an anti-inflammatory role.However,the underlying mechanism is still unclear.AIM To explore the mechanism of alk-SMase anti-inflammatory effects on intestinal barrier function and oxidative stress in dextran sulfate sodium(DSS)-induced colitis.METHODS Mice were administered 3%DSS drinking water,and disease activity index was determined to evaluate the status of colitis.Intestinal permeability was evaluated by gavage administration of fluorescein isothiocyanate dextran,and bacterial translocation was evaluated by measuring serum lipopolysaccharide.Intestinal epithelial cell ultrastructure was observed by electron microscopy.Western blotting and quantitative real-time reverse transcription-polymerase chain reaction were used to detect the expression of intestinal barrier proteins and mRNA,respectively.Serum oxidant and antioxidant marker levels were analyzed using commercial kits to assess oxidative stress levels.RESULTS Compared to wild-type(WT)mice,inflammation and intestinal permeability in alk-SMase knockout(KO)mice were more severe beginning 4 d after DSS induction.The mRNA and protein levels of intestinal barrier proteins,including zonula occludens-1,occludin,claudin-3,claudin-5,claudin-8,mucin 2,and secretory immunoglobulin A,were significantly reduced on 4 d after DSS treatment.Ultrastructural observations revealed progressive damage to the tight junctions of intestinal epithelial cells.Furthermore,by day 4,mitochondria appeared swollen and degenerated.Additionally,compared to WT mice,serum malondialdehyde levels in KO mice were higher,and the antioxidant capacity was significantly lower.The expression of the transcription factor nuclear factor erythroid 2-related factor 2(Nrf2)in the colonic mucosal tissue of KO mice was significantly decreased after DSS treatment.mRNA levels of Nrf2-regulated downstream antioxidant enzymes were also decreased.Finally,colitis in KO mice could be effectively relieved by the injection of tertiary butylhydroquinone,which is an Nrf2 activator.CONCLUSION Alk-SMase regulates the stability of the intestinal mucosal barrier and enhances antioxidant activity through the Nrf2 signaling pathway.展开更多
Dextran in sugarcane production process is formed by Leuconostoc rnesenteroides. The content levels of dextran is related to sugarcane varieties, field condition （planting pattern, temperature, humidity, sunlight, so...Dextran in sugarcane production process is formed by Leuconostoc rnesenteroides. The content levels of dextran is related to sugarcane varieties, field condition （planting pattern, temperature, humidity, sunlight, soil, foreign material）, de- gree of injury （refractory cane, harvesting methods）, and can be rapidly and accu- rately measured by Dextran Immunonephelometric Test Kit. The presence of dextran indicates that sucrose has been lost, so sugarcane dextran is a direct and reliable indicator to measure sugarcane freshness and quality.展开更多
Aim To investigate the effect in berberine chloride （BER） on experimental ulcerative colitis in mice. Methods BALB/C mice in 6 groups were allowed to drink either 4% dextran sulfate sodium （DSS） solution or distil...Aim To investigate the effect in berberine chloride （BER） on experimental ulcerative colitis in mice. Methods BALB/C mice in 6 groups were allowed to drink either 4% dextran sulfate sodium （DSS） solution or distilled water freely with different doses of BER （15 mg·kg^-1, 45 mg·kg^-1, 150 mg·kg^-1） or sallcylazosulfapyridine （SASP, 520 mg·kg^-1）, and solvent （0. 2 mL/10 mg Wt） once a day for 7 d, respectively. The symptom of ulcerative colitis was evaluated by disease activity index （DAI）. Myeloperoxidase （MPO） and superoxide dismutase （SOD） activities and malondialdehyde （MDA） content were determined by HE staining and immunohistochemistry of expressions of NF-κB p65 and intercellular adhesion molecule 1 （ ICAM-1 ） proteins to observe the damage to colon tissues and possible mechanisms. Results DAI, MPO activity, MDA content and expressions of ICAM-1 and NF-κB p65 were markedly increased, while SOD activity decreased in DSS-treated mice. Treatment of mice with different doses of BER or SASP significantly decreased DAI, MPO activity and MDA content, improved histological changes of colon tissues, blunted the expressions of NF-κB p65 and ICAM-1 proteins, and enhanced SOD activity. Conclusion Berberine chloride has excellent therapeutic effect on ulcerative colitis caused by DSS in mice. The possible mechanism may be related to its antioxidant and anti-inflammatory activities associated with inhibiting the NF-κB activation and ICAM-1 expression.展开更多
Inflammatory bowel diseases(IBD),including Crohn's disease and ulcerative colitis,are complex diseases that result from the chronic dysregulated immune response in the gastrointestinal tract. The exact etiology is...Inflammatory bowel diseases(IBD),including Crohn's disease and ulcerative colitis,are complex diseases that result from the chronic dysregulated immune response in the gastrointestinal tract. The exact etiology is not fully understood,but it is accepted that it occurs when an inappropriate aggressive inflammatory respon-se in a genetically susceptible host due to inciting environmental factors occurs. To investigate the path-ogenesis and etiology of human IBD,various animal models of IBD have been developed that provided indispensable insights into the histopathological and morphological changes as well as factors associated with the pathogenesis of IBD and evaluation of therapeutic options in the last few decades. The most widely used experimental model employs dextran sodium sulfate(DSS) to induce epithelial damage. The DSS colitis model in IBD research has advantages over other various chemically induced experimental models due to its rapidity,simplicity,reproducibility and controllability. In this manuscript,we review the newer publicized advances of research in murine colitis models that focus upon the disruption of the barrier function of the intestine,effects of mucin on the development of colitis,alterations found in microbial balance and resultant changes in the metabolome specifically in the DSS colitis murine model and its relation to the pathogenesis of IBD.展开更多
AIM:To investigate the effects of mesenchymal stem cells(MSCs)on dextran sulfate sodium-induced inflammatory bowel disease(IBD).METHODS:C57BL/6 mice were fed 3.5%(g/L)dextran sulfate sodium.On day seven,the mice recei...AIM:To investigate the effects of mesenchymal stem cells(MSCs)on dextran sulfate sodium-induced inflammatory bowel disease(IBD).METHODS:C57BL/6 mice were fed 3.5%(g/L)dextran sulfate sodium.On day seven,the mice received intraperitoneal injections of 1×106 MSCs.The survival rate,disease activity index values,and body weight,were monitored daily.On day ten,colon lengths and histopathologic changes were assessed.In addition,immunoregulatory changes following MSC administration were evaluated by determining the levels of effector T cell responses in the spleen and mesenteric lymph nodes,and the expression levels of inflammatory cytokines in homogenized colons.RESULTS:Intraperitoneal administration of MSCs did not prevent development of colitis and did not reduce the clinicopathologic severity of IBD.No significant difference was evident in either survival rate or disease activity index score between the control and MSCtreated group.Day ten-sacrificed mice exhibited no significant difference in either colon length or histopathologic findings.Indeed,the MSC-treated group exhibited elevated levels of interleukin(IL)-6 and transforming growth factor-β,and a reduced level of IL-10,in spleens,mesenteric lymph nodes,and homogenized colons.The IL-17 level was lower in the mesenteric lymph nodes of the MSC-treated group(P=0.0126).In homogenized colons,the IL-17 and tumor necrosis factor-α(P=0.0092)expression levels were also lower in the treated group.CONCLUSION:MSC infusion provided no significanthistopathologic or clinical improvement,thus representing a limited therapeutic approach for IBD.Functional enhancement of MSCs is needed in further study.展开更多
Objective:To investigate the effects of pectic polysaccharides extracted from Rauwolfia verticillata(Lour.) Baill.var.hainanensis Tsiang on an experimental murine colitis model.Methods:Experimental colitis was induced...Objective:To investigate the effects of pectic polysaccharides extracted from Rauwolfia verticillata(Lour.) Baill.var.hainanensis Tsiang on an experimental murine colitis model.Methods:Experimental colitis was induced by dextran sulfate sodium(DSS),and mice were divided into 4 groups:control.DSS alone.DSS plus SASP,DSS plus pectic polysaccharides.The disease activity index(DAI) and histological score were observed.The tumor necrosis factor(TNF)-α and interleukin(IL)-17 levels were measured by enzyme-linked immunosorbent assay.I κ B and NF-κB p65 expression were assessed by western blot analysis.Myeloperoxidase(MPO) activity was determined by using MPO assay kit.Re.sults:Administration of pectic polysaccharides significantly reduced the severity of DSS-induced colitis as assessed by DAT and histological score,and resulted in down regulation of MPO activity and NF-κB p65 expression and subsequent degradation of IκB protein,strikingly reduced the production of TNF-α and IL-17.Conclusions:Pectic polysaccharides extracted from Rauvolfia verticillata(Lour.)Baill.var.hainanensis Tsiang exerts beneficial effects in experimental colitis and may therefore provide a useful therapeutic approach for the treatment of UC.展开更多
BACKGROUND Intestinal mucosal barrier dysfunction plays an important role in the pathogenesis of ulcerative colitis(UC).Recent studies have revealed that impaired autophagy is associated with intestinal mucosal dysfun...BACKGROUND Intestinal mucosal barrier dysfunction plays an important role in the pathogenesis of ulcerative colitis(UC).Recent studies have revealed that impaired autophagy is associated with intestinal mucosal dysfunction in the mucosa of colitis mice.Resveratrol exerts anti-inflammatory functions by regulating autophagy.AIM To investigate the effect and mechanism of resveratrol on protecting the integrity of the intestinal mucosal barrier and anti-inflammation in dextran sulfate sodium(DSS)-induced ulcerative colitis mice.METHODS Male C57BL/6 mice were divided into four groups:negative control group,DSS model group,DSS+resveratrol group,and DSS+5-aminosalicylic acid group.The severity of colitis was assessed by the disease activity index,serum inflammatory cytokines were detected by enzyme-linked immunosorbent assay.Colon tissues were stained with haematoxylin and eosin,and mucosal damage was evaluated by mean histological score.The expression of occludin and ZO-1 in colon tissue was evaluated using immunohistochemical analysis.In addition,the expression of autophagy-related genes was determined using reverse transcription-polymerase chain reaction and Western-blot,and morphology of autophagy was observed by transmission electron microscopy.RESULTS The resveratrol treatment group showed a 1.72-fold decrease in disease activity index scores and 1.42,3.81,and 1.65-fold decrease in the production of the inflammatory cytokine tumor necrosis factor-α,interleukin-6 and interleukin-1β,respectively,in DSS-induced colitis mice compared with DSS group(P<0.05).The expressions of the tight junction proteins occludin and ZO-1 in DSS model group were decreased,and were increased in resveratrol-treated colitis group.Resveratrol also increased the levels of LC3B(by 1.39-fold compared with DSS group)and Beclin-1(by 1.49-fold compared with DSS group)(P<0.05),as well as the number of autophagosomes,which implies that the resveratrol may alleviate intestinal mucosal barrier dysfunction in DSS-induced UC mice by enhancing autophagy.CONCLUSION Resveratrol treatment decreased the expression of inflammatory factors,increased the expression of tight junction proteins and alleviated UC intestinal mucosal barrier dysfunction;this effect may be achieved by enhancing autophagy in intestinal epithelial cells.展开更多
AIM To investigate the temporal clinical, proteomic, histological and cellular immune profiles of dextran sulfate sodium(DSS)-induced acute colitis.METHODS Acute colitis was induced in C57 BL/6 female mice by administ...AIM To investigate the temporal clinical, proteomic, histological and cellular immune profiles of dextran sulfate sodium(DSS)-induced acute colitis.METHODS Acute colitis was induced in C57 BL/6 female mice by administration of 1%, 2% or 3% DSS in drinking water for 7 d. Animals were monitored daily for weight loss, stool consistency and blood in the stool, while spleens and colons were harvested on day 8. A time course analysis was performed in mice ingesting 3% DSS, which included colon proteomics through multiplex assay, colon histological scoring by a blinded investigator, and immune response through flow cytometry or immunohistochemistry of the spleen, mesenteric lymph node and colon.RESULTS Progressive worsening of clinical colitis was observed with increasing DSS from 1% to 3%. In mice ingesting 3% DSS, colon shortening and increase in proinflammatory factors starting at day 3 was observed, with increased spleen weights at day 6 and day 8. This coincided with cellular infiltration in the colon from day 2 to day 8, with progressive accumulation of macrophages F4/80^+, T helper CD4^+(Th), T cytotoxic CD8^+(Tcyt) and T regulatory CD25^+(Treg) cells, and progressive changes in colonic pathology including destruction of crypts, loss of goblet cells and depletion of the epithelial barrier. Starting on day 4, mesenteric lymph node and/or spleen presented with lower levels of Treg, Th and Tcyt cells, suggesting an immune cell tropism to the gut. CONCLUSION These results demonstrate that the severity of experimental colitis is dependent on DSS concentration, correlated with clinical, proteomic, histological and cellular immune response on 3% DSS.展开更多
In this study, biotinylated dextran amine （BDA） was microinjected into the left cortical motor area of the canine brain. Fluorescence microscopy results showed that a large amount of BDA-labeled pyramidal cells were...In this study, biotinylated dextran amine （BDA） was microinjected into the left cortical motor area of the canine brain. Fluorescence microscopy results showed that a large amount of BDA-labeled pyramidal cells were visible in the left cortical motor area after injection. In the left medulla oblongata, the BDA-labeled corticospinal tract was evenly distributed, with green fluorescence that had a clear boundary with the surrounding tissue. The BDA-positive corticospinal tract entered into the right lateral funiculus of the spinal cord and descended into the posterior part of the right lateral funiculus, close to the posterior horn, from cervical to sacral segments. There was a small amount of green fluorescence in the sacral segment. The distribution of BDA labeling in the canine central nervous system was consistent with the course of the corticospinal tract. Fluorescence labeling for BDA gradually diminished with time after injection. Our findings indicate that the BDA anterograde tracing technique can be used to visualize the localization and trajectory of the corticospinal tract in the canine central nervous system.展开更多
BACKGROUND Intestinal inflammation is a common digestive tract disease, which is usually treated with hormone medicines. Hormone medicines are effective to some extent, but long-term use of them may bring about many c...BACKGROUND Intestinal inflammation is a common digestive tract disease, which is usually treated with hormone medicines. Hormone medicines are effective to some extent, but long-term use of them may bring about many complications.AIM To explore the protective effects of panax notoginseng saponin(PNS) against dextran sulfate sodium(DSS)-induced intestinal inflammatory injury through phosphoinositide-3-kinase protein kinase B(PI3K/AKT) signaling pathway inhibition in rats.METHODS Colitis rat models were generated via DSS induction, and rats were divided into control(no modeling), DSS, DSS + PNS 50 mg/k, and DSS + PNS 100 mg/kg groups. Then, the intestinal injury, oxidative stress parameters, inflammatory indices, tight junction proteins, apoptosis, macrophage polarization, and TLR4/AKT signaling pathway in colon tissues from rats in each of the groups were detected. The PI3 K/AKT signaling pathway in the colon tissue of rats was blocked using the PI3K/AKT signaling pathway inhibitor, LY294002.RESULTS Compared with rats in the control group, rats in the DSS group showed significantly shortened colon lengths, and significantly increased disease activity indices, oxidative stress reactions and inflammatory indices, as well as significantly decreased expression of tight junction-associated proteins. In addition, the DSS group showed significantly increased apoptotic cell numbers,and showed significantly increased M1 macrophages in spleen and colon tissues.They also showed significantly decreased M2 macrophages in colon tissues, as well as activation of the PI3K/AKT signaling pathway(all P < 0.05). Compared with rats in the DSS group, rats in the DSS + PNS group showed significantly lengthened colon lengths, decreased disease activity indices, and significantly alleviated oxidative stress reactions and inflammatory responses. In addition, this group showed significantly increased expression of tight junction-associated proteins, significantly decreased apoptotic cell numbers, and significantly decreased M1 macrophages in spleen and colon tissues. This group further showed significantly increased M2 macrophages in colon tissues, and significantly suppressed activation of the PI3K/AKT signaling pathway, as well as a dose dependency(all P < 0.05). When the PI3K/AKT signaling pathway was inhibited, the apoptosis rate of colon tissue cells in the DSS + LY294002 group was significantly lower than that of the DSS group(P < 0.05).CONCLUSION PNS can protect rats against DSS-induced intestinal inflammatory injury by inhibiting the PI3K/AKT signaling pathway, and therefore may be potentially used in the future as a drug for colitis.展开更多
AIM: To study whether matrix metalloproteinase-9 (MMP-9) is a key factor in epithelial damage in the dextran sodium sulphate (DSS) model of colitis in mice.METHODS: MMP-9-deficient and wild-type (wt) mice were given 5...AIM: To study whether matrix metalloproteinase-9 (MMP-9) is a key factor in epithelial damage in the dextran sodium sulphate (DSS) model of colitis in mice.METHODS: MMP-9-deficient and wild-type (wt) mice were given 5% DSS in drinking water for 5 d followed by recovery up to 7 d. On d 5 and 12 after induction of colitis, gelatinases, MMP-2 and MMP-9, were measured in homogenates of colonic tissue by zymography and Western blot, whereas tissue inhibitor of metalloproteinases (TIMPs) were measured by reverse zymography. The gelatinolytic activity was also determined in supernatants of polymorphonuclear leukocytes (PMN) isolated from mice blood. Moreover, intestinal epithelial cells were stimulated with TNF-α to study whether these cells were able to produce MMPs. Finally, colonic mucosal lesions were measured by microscopic examination. RESULTS: On d 5 of colitis, the activity of MMP-9 was increased in homogenates of colonic tissues (0.24 ± 0.1 vs 21.3 ± 6.4, P < 0.05) and PMN from peripheral blood in wt (0.5 ± 0.1 vs 10.4 ± 0.7, P < 0.05), but not in MMP-9-deficient animals. The MMP-9 activity was also up-regulated by TNF-α in epithelial intestinal cells (2.5 ± 0.5 vs 14.7 ± 3.0, P < 0.05). Although colitis also led to increase of TIMP-1 activity, the MMP-9/TIMP-1 balance remained elevated. Finally, in the MMP-9-deficient colitic mice both the extent and severity of intestinal epithelialinjury were significantly attenuated when compared with wt mice. CONCLUSION: We conclude that DSS induced colitis is markedly attenuated in animals lacking MMP-9. This suggests that intestinal injury induced by DSS is modu-lated by MMP-9 and that inhibition of this gelatinase may reduce inflammation.展开更多
基金supported by the Mae Fah Luang University Research Development Grant 2023,Mae Fah Luang University,Chiang Rai Thailand(Grant no.661B07007 to KW)the Technology and Innovation-Based Enterprise Development Fund:Fund(Grant no.YP043/2565 to AO and PW).
文摘Objective:To investigate the effect of synbiotic mulberry on kidney injury in a dextran sodium sulfate(DSS)-induced colitis model.Methods:Male Wistar rats were given drinking water containing 4%DSS for 7 days.Subsequently,the rats were treated by oral gavage with synbiotic mulberry at 250,500,and 1000 mg/kg,sulfasalazine at 100 mg/kg,or synbiotic at 1000 mg/kg for an additional 7 days while receiving 0.4%DSS in drinking water.The severity of colitis was evaluated based on the disease activity index score.On day 14,plasma was collected,and the kidneys were harvested to evaluate kidney injury parameters and histological changes.In addition,the expression of genes associated with kidney injury was determined by quantitative RT-PCR.Results:Treatment with all doses of synbiotic mulberry significantly lowered the disease activity index score,accompanied by reductions in kidney histopathological changes,malondialdehyde concentration,and plasma cystatin C levels.Kidney fibrosis was also ameliorated by 500 and 1000 mg/kg of synbiotic mulberry.Treatment with 250 and 500 mg/kg of synbiotic mulberry downregulated IL-18 mRNA expression,while KIM-1 mRNA expression was reduced and plasma lipopolysaccharide-binding protein level was restored by 1000 mg/kg of synbiotic mulberry.Conclusions:Synbiotic mulberry ameliorates kidney injury in rats with DSS-induced colitis.It may be further explored as a treatment of kidney injury under colitis conditions.
基金funded by grants from Beijing Fishery Innovation Team Project(BAIC07-2023-13)National Natural Science Foundation of China(32201994)。
文摘Chondroitin sulfate(CS)is one of the main bioactive compounds in animal cartilage.In this study,the antiinflammatory activity of sturgeon-derived chondroitin sulfate(SCS)was evaluated in the dextran sulfate sodium(DSS)-induced BALB/c mice model.Orally administration of SCS significantly alleviated the DSSinduced colitis symptoms,including the reduction of crypt depth,inhibition of the abnormal crypt foci formation,down-regulation of the proinflammatory biomarkers(NO,interleukin(IL)-6,IL-1βand tumor necrosis factor-α)and up-regulation of the anti-inflammatory biomarkers(IL-10 and IL-4).The gut microbiota analysis revealed that SCS alters the intestinal microbiota composition in colitis mice,especially the increase of the relative abundance of Ruminococcaceae and Lachnospiraceae.This alternation further induced primary bile acids convert into secondary bile acids.With SCS administration,the levels of deoxycholic acid(DCA)and litho cholic acid(LCA)were increased by 1.5-and 2.5-fold,respectively.The stimulated secretion of DCA and LCA showed further activation of the NF-κB signaling pathway,thereby suppressing the inflammatory response and attenuating inflammatory bowel disease(IBD)in mice.This study provided a valuable strategy for colitis prevention and treatment with sturgeon cartilage by-products.
基金the National Natural Science Foundation of China(Grant Nos.92478133,81930097,and 82151223)by the State Key Laboratory of Natural and Biomimetic Drugs(Grant No.K202430).
文摘Idiopathic pulmonary fibrosis(IPF)is a progressive and fatal interstitial lung disease characterized by excessive fibrotic remodeling,for which effective therapeutic options remain severely limited.Among the pathogenic mechanisms implicated in IPF,epithelial-to-mesenchymal transition(EMT)is recognized as a pivotal driver of fibroblast activation and extracellular matrix deposition.In this study,we aimed to develop low-molecular-weight dextran sulfate sodium(LMW-DSS)derivatives and assess their capacity to interfere with EMT,thereby offering novel therapeutic avenues for IPF management.Starting with dextran(2 kDa)as a precursor,we successfully synthesized two sulfated derivatives,DSS-LS and DSS-HS,via distinct sulfonation processes.Using a TGF-β1-stimulated A549 alveolar epithelial cell model,we demonstrated that LMW-DSS compounds exhibited no cytotoxicity,as validated by CCK-8 viability assays.Importantly,Transwell migration assays revealed that LMW-DSS markedly attenuated TGF-β1-induced A549 cell migration,indicating a potent anti-fibrotic effect.Moreover,qPCR and Western blotting analyses confirmed that LMW-DSS significantly suppressed the expression and secretion of key pro-fibrotic mediators,including TGF-β1 and VEGF-A,and downregulated critical EMT-associated markers such as Snail and vimentin.Notably,reducedα-SMA expression following LMW-DSS treatment further substantiated its role in hindering EMT progression.Collectively,these findings highlighted the capacity of LMW-DSS to effectively impede EMT and fibrotic processes,thereby delaying the progression of pulmonary fibrosis.This work not only underscored the therapeutic potential of LMW-DSS in IPF but also provided compelling experimental evidence to support its development as a promising anti-fibrotic agent for clinical application.
基金supported by the Natural Science Foundation of Jiangsu Province (BK20200084)The National Natural Science Foundation of China (U1903205 and 31972971)Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province。
文摘Inflammatory bowel disease(IBD)is a complex relapsing inflammatory disease in the gut and is driven by complicated host-gut microbiome interactions.Gut commensals have shown different functions in IBD prevention and treatment.To gain a mechanistic understanding of how different commensals affect intestinal inflammation,we compared the protective effects of 6 probiotics(belonging to the genera Akkermansia,Bifidobacterium,Clostridium,and Enterococcus)on dextran sulfate sodium(DSS)-induced colitis in mice with or without gut microbiota.Anti-inflammatory properties(ratio of interleukin(IL)-10 and IL-12)of these strains were also evaluated in an in vitro mesenteric lymph nodes(MLN)co-culture system.Results showed that 4 probiotics(belonging to the species Bifidobacterium breve,Bifidobacterium bifidum,and Enterococcus faecalis)can alleviate colitis in normal mice.The probiotic strains differed in regulating the intestinal microbiota,cytokines(IL-10,IL-1βand interferon(IFN)-γ),and tight junction function(Zonulin-1 and Occludin).By constrast,Akkermansia muciniphila AH39 and Clostridium butyricum FHuNHHMY49T1 were not protective.Interestingly,B.breve JSNJJNM2 with high anti-inflammatory potential in the MLN model could relieve colitis symptoms in antibiotic cocktail(Abx)-treated mice.Meanwhile,E.faecalis FJSWX25M1induced low levels of cytokines in vitro and showed no beneficial effects.Therefore,we provided insight into the clinical application of probiotics in IBD treatment.
基金the Natural Science Foundation of Hainan Province,No.823MS046the Talent Program of Hainan Medical University,No.XRC2022007.
文摘BACKGROUND Ulcerative colitis is a chronic inflammatory disease of the colon with an unknown etiology.Alkaline sphingomyelinase(alk-SMase)is specifically expressed by intestinal epithelial cells,and has been reported to play an anti-inflammatory role.However,the underlying mechanism is still unclear.AIM To explore the mechanism of alk-SMase anti-inflammatory effects on intestinal barrier function and oxidative stress in dextran sulfate sodium(DSS)-induced colitis.METHODS Mice were administered 3%DSS drinking water,and disease activity index was determined to evaluate the status of colitis.Intestinal permeability was evaluated by gavage administration of fluorescein isothiocyanate dextran,and bacterial translocation was evaluated by measuring serum lipopolysaccharide.Intestinal epithelial cell ultrastructure was observed by electron microscopy.Western blotting and quantitative real-time reverse transcription-polymerase chain reaction were used to detect the expression of intestinal barrier proteins and mRNA,respectively.Serum oxidant and antioxidant marker levels were analyzed using commercial kits to assess oxidative stress levels.RESULTS Compared to wild-type(WT)mice,inflammation and intestinal permeability in alk-SMase knockout(KO)mice were more severe beginning 4 d after DSS induction.The mRNA and protein levels of intestinal barrier proteins,including zonula occludens-1,occludin,claudin-3,claudin-5,claudin-8,mucin 2,and secretory immunoglobulin A,were significantly reduced on 4 d after DSS treatment.Ultrastructural observations revealed progressive damage to the tight junctions of intestinal epithelial cells.Furthermore,by day 4,mitochondria appeared swollen and degenerated.Additionally,compared to WT mice,serum malondialdehyde levels in KO mice were higher,and the antioxidant capacity was significantly lower.The expression of the transcription factor nuclear factor erythroid 2-related factor 2(Nrf2)in the colonic mucosal tissue of KO mice was significantly decreased after DSS treatment.mRNA levels of Nrf2-regulated downstream antioxidant enzymes were also decreased.Finally,colitis in KO mice could be effectively relieved by the injection of tertiary butylhydroquinone,which is an Nrf2 activator.CONCLUSION Alk-SMase regulates the stability of the intestinal mucosal barrier and enhances antioxidant activity through the Nrf2 signaling pathway.
基金Supported by Special Fund for Construction Project of Bagui ScholarsSpecial Fund for Modern Agricultural Industry Technology System Construction(CARS-20-4-5)
文摘Dextran in sugarcane production process is formed by Leuconostoc rnesenteroides. The content levels of dextran is related to sugarcane varieties, field condition （planting pattern, temperature, humidity, sunlight, soil, foreign material）, de- gree of injury （refractory cane, harvesting methods）, and can be rapidly and accu- rately measured by Dextran Immunonephelometric Test Kit. The presence of dextran indicates that sucrose has been lost, so sugarcane dextran is a direct and reliable indicator to measure sugarcane freshness and quality.
基金AProject of the Health Bureau of Chongqing (No.2004-B-31)
文摘Aim To investigate the effect in berberine chloride （BER） on experimental ulcerative colitis in mice. Methods BALB/C mice in 6 groups were allowed to drink either 4% dextran sulfate sodium （DSS） solution or distilled water freely with different doses of BER （15 mg·kg^-1, 45 mg·kg^-1, 150 mg·kg^-1） or sallcylazosulfapyridine （SASP, 520 mg·kg^-1）, and solvent （0. 2 mL/10 mg Wt） once a day for 7 d, respectively. The symptom of ulcerative colitis was evaluated by disease activity index （DAI）. Myeloperoxidase （MPO） and superoxide dismutase （SOD） activities and malondialdehyde （MDA） content were determined by HE staining and immunohistochemistry of expressions of NF-κB p65 and intercellular adhesion molecule 1 （ ICAM-1 ） proteins to observe the damage to colon tissues and possible mechanisms. Results DAI, MPO activity, MDA content and expressions of ICAM-1 and NF-κB p65 were markedly increased, while SOD activity decreased in DSS-treated mice. Treatment of mice with different doses of BER or SASP significantly decreased DAI, MPO activity and MDA content, improved histological changes of colon tissues, blunted the expressions of NF-κB p65 and ICAM-1 proteins, and enhanced SOD activity. Conclusion Berberine chloride has excellent therapeutic effect on ulcerative colitis caused by DSS in mice. The possible mechanism may be related to its antioxidant and anti-inflammatory activities associated with inhibiting the NF-κB activation and ICAM-1 expression.
基金Supported by the Department of Veterans Affairs,Office of Research and Development(Biomedical Laboratory Research and Development)No.BX001155
文摘Inflammatory bowel diseases(IBD),including Crohn's disease and ulcerative colitis,are complex diseases that result from the chronic dysregulated immune response in the gastrointestinal tract. The exact etiology is not fully understood,but it is accepted that it occurs when an inappropriate aggressive inflammatory respon-se in a genetically susceptible host due to inciting environmental factors occurs. To investigate the path-ogenesis and etiology of human IBD,various animal models of IBD have been developed that provided indispensable insights into the histopathological and morphological changes as well as factors associated with the pathogenesis of IBD and evaluation of therapeutic options in the last few decades. The most widely used experimental model employs dextran sodium sulfate(DSS) to induce epithelial damage. The DSS colitis model in IBD research has advantages over other various chemically induced experimental models due to its rapidity,simplicity,reproducibility and controllability. In this manuscript,we review the newer publicized advances of research in murine colitis models that focus upon the disruption of the barrier function of the intestine,effects of mucin on the development of colitis,alterations found in microbial balance and resultant changes in the metabolome specifically in the DSS colitis murine model and its relation to the pathogenesis of IBD.
基金Supported by Korea Healthcare Technology R and D Project No.HI12C0193(A120241)the Ministry for Health,Welfare,and Family Affairs,South Korea
文摘AIM:To investigate the effects of mesenchymal stem cells(MSCs)on dextran sulfate sodium-induced inflammatory bowel disease(IBD).METHODS:C57BL/6 mice were fed 3.5%(g/L)dextran sulfate sodium.On day seven,the mice received intraperitoneal injections of 1×106 MSCs.The survival rate,disease activity index values,and body weight,were monitored daily.On day ten,colon lengths and histopathologic changes were assessed.In addition,immunoregulatory changes following MSC administration were evaluated by determining the levels of effector T cell responses in the spleen and mesenteric lymph nodes,and the expression levels of inflammatory cytokines in homogenized colons.RESULTS:Intraperitoneal administration of MSCs did not prevent development of colitis and did not reduce the clinicopathologic severity of IBD.No significant difference was evident in either survival rate or disease activity index score between the control and MSCtreated group.Day ten-sacrificed mice exhibited no significant difference in either colon length or histopathologic findings.Indeed,the MSC-treated group exhibited elevated levels of interleukin(IL)-6 and transforming growth factor-β,and a reduced level of IL-10,in spleens,mesenteric lymph nodes,and homogenized colons.The IL-17 level was lower in the mesenteric lymph nodes of the MSC-treated group(P=0.0126).In homogenized colons,the IL-17 and tumor necrosis factor-α(P=0.0092)expression levels were also lower in the treated group.CONCLUSION:MSC infusion provided no significanthistopathologic or clinical improvement,thus representing a limited therapeutic approach for IBD.Functional enhancement of MSCs is needed in further study.
基金supported by National Natural Science Foundation of China(Grant No.81360603)Natural Science Foundation of Hainan Province(Grant No.813215)
文摘Objective:To investigate the effects of pectic polysaccharides extracted from Rauwolfia verticillata(Lour.) Baill.var.hainanensis Tsiang on an experimental murine colitis model.Methods:Experimental colitis was induced by dextran sulfate sodium(DSS),and mice were divided into 4 groups:control.DSS alone.DSS plus SASP,DSS plus pectic polysaccharides.The disease activity index(DAI) and histological score were observed.The tumor necrosis factor(TNF)-α and interleukin(IL)-17 levels were measured by enzyme-linked immunosorbent assay.I κ B and NF-κB p65 expression were assessed by western blot analysis.Myeloperoxidase(MPO) activity was determined by using MPO assay kit.Re.sults:Administration of pectic polysaccharides significantly reduced the severity of DSS-induced colitis as assessed by DAT and histological score,and resulted in down regulation of MPO activity and NF-κB p65 expression and subsequent degradation of IκB protein,strikingly reduced the production of TNF-α and IL-17.Conclusions:Pectic polysaccharides extracted from Rauvolfia verticillata(Lour.)Baill.var.hainanensis Tsiang exerts beneficial effects in experimental colitis and may therefore provide a useful therapeutic approach for the treatment of UC.
基金Supported by the National Natural Science Foundation of China,No.81600414Medical Health Science and Technology Project of Zhejiang Provincial Health Commission,No.2018255969Zhejiang TCM Science and Technology Project,No.2016ZA123 and No.2018ZA013.
文摘BACKGROUND Intestinal mucosal barrier dysfunction plays an important role in the pathogenesis of ulcerative colitis(UC).Recent studies have revealed that impaired autophagy is associated with intestinal mucosal dysfunction in the mucosa of colitis mice.Resveratrol exerts anti-inflammatory functions by regulating autophagy.AIM To investigate the effect and mechanism of resveratrol on protecting the integrity of the intestinal mucosal barrier and anti-inflammation in dextran sulfate sodium(DSS)-induced ulcerative colitis mice.METHODS Male C57BL/6 mice were divided into four groups:negative control group,DSS model group,DSS+resveratrol group,and DSS+5-aminosalicylic acid group.The severity of colitis was assessed by the disease activity index,serum inflammatory cytokines were detected by enzyme-linked immunosorbent assay.Colon tissues were stained with haematoxylin and eosin,and mucosal damage was evaluated by mean histological score.The expression of occludin and ZO-1 in colon tissue was evaluated using immunohistochemical analysis.In addition,the expression of autophagy-related genes was determined using reverse transcription-polymerase chain reaction and Western-blot,and morphology of autophagy was observed by transmission electron microscopy.RESULTS The resveratrol treatment group showed a 1.72-fold decrease in disease activity index scores and 1.42,3.81,and 1.65-fold decrease in the production of the inflammatory cytokine tumor necrosis factor-α,interleukin-6 and interleukin-1β,respectively,in DSS-induced colitis mice compared with DSS group(P<0.05).The expressions of the tight junction proteins occludin and ZO-1 in DSS model group were decreased,and were increased in resveratrol-treated colitis group.Resveratrol also increased the levels of LC3B(by 1.39-fold compared with DSS group)and Beclin-1(by 1.49-fold compared with DSS group)(P<0.05),as well as the number of autophagosomes,which implies that the resveratrol may alleviate intestinal mucosal barrier dysfunction in DSS-induced UC mice by enhancing autophagy.CONCLUSION Resveratrol treatment decreased the expression of inflammatory factors,increased the expression of tight junction proteins and alleviated UC intestinal mucosal barrier dysfunction;this effect may be achieved by enhancing autophagy in intestinal epithelial cells.
基金supported by the Intramural Research Programs of the Clinical Center, the National Institute of Biomedical Imaging and Bioengineering at the National Institutes of Health and CAPES (Coordination for the Training of Higher Education Personnel Ministry of Education) from Brazil
文摘AIM To investigate the temporal clinical, proteomic, histological and cellular immune profiles of dextran sulfate sodium(DSS)-induced acute colitis.METHODS Acute colitis was induced in C57 BL/6 female mice by administration of 1%, 2% or 3% DSS in drinking water for 7 d. Animals were monitored daily for weight loss, stool consistency and blood in the stool, while spleens and colons were harvested on day 8. A time course analysis was performed in mice ingesting 3% DSS, which included colon proteomics through multiplex assay, colon histological scoring by a blinded investigator, and immune response through flow cytometry or immunohistochemistry of the spleen, mesenteric lymph node and colon.RESULTS Progressive worsening of clinical colitis was observed with increasing DSS from 1% to 3%. In mice ingesting 3% DSS, colon shortening and increase in proinflammatory factors starting at day 3 was observed, with increased spleen weights at day 6 and day 8. This coincided with cellular infiltration in the colon from day 2 to day 8, with progressive accumulation of macrophages F4/80^+, T helper CD4^+(Th), T cytotoxic CD8^+(Tcyt) and T regulatory CD25^+(Treg) cells, and progressive changes in colonic pathology including destruction of crypts, loss of goblet cells and depletion of the epithelial barrier. Starting on day 4, mesenteric lymph node and/or spleen presented with lower levels of Treg, Th and Tcyt cells, suggesting an immune cell tropism to the gut. CONCLUSION These results demonstrate that the severity of experimental colitis is dependent on DSS concentration, correlated with clinical, proteomic, histological and cellular immune response on 3% DSS.
基金Fsupported by the Priority Academic Development Program of Jiangsu Higher Education Institutions
文摘In this study, biotinylated dextran amine （BDA） was microinjected into the left cortical motor area of the canine brain. Fluorescence microscopy results showed that a large amount of BDA-labeled pyramidal cells were visible in the left cortical motor area after injection. In the left medulla oblongata, the BDA-labeled corticospinal tract was evenly distributed, with green fluorescence that had a clear boundary with the surrounding tissue. The BDA-positive corticospinal tract entered into the right lateral funiculus of the spinal cord and descended into the posterior part of the right lateral funiculus, close to the posterior horn, from cervical to sacral segments. There was a small amount of green fluorescence in the sacral segment. The distribution of BDA labeling in the canine central nervous system was consistent with the course of the corticospinal tract. Fluorescence labeling for BDA gradually diminished with time after injection. Our findings indicate that the BDA anterograde tracing technique can be used to visualize the localization and trajectory of the corticospinal tract in the canine central nervous system.
基金National Natural Science Foundation of China,No.81704059Scientific Research Project of Hebei Province Traditional Chinese Medicine Administration,No.2017130。
文摘BACKGROUND Intestinal inflammation is a common digestive tract disease, which is usually treated with hormone medicines. Hormone medicines are effective to some extent, but long-term use of them may bring about many complications.AIM To explore the protective effects of panax notoginseng saponin(PNS) against dextran sulfate sodium(DSS)-induced intestinal inflammatory injury through phosphoinositide-3-kinase protein kinase B(PI3K/AKT) signaling pathway inhibition in rats.METHODS Colitis rat models were generated via DSS induction, and rats were divided into control(no modeling), DSS, DSS + PNS 50 mg/k, and DSS + PNS 100 mg/kg groups. Then, the intestinal injury, oxidative stress parameters, inflammatory indices, tight junction proteins, apoptosis, macrophage polarization, and TLR4/AKT signaling pathway in colon tissues from rats in each of the groups were detected. The PI3 K/AKT signaling pathway in the colon tissue of rats was blocked using the PI3K/AKT signaling pathway inhibitor, LY294002.RESULTS Compared with rats in the control group, rats in the DSS group showed significantly shortened colon lengths, and significantly increased disease activity indices, oxidative stress reactions and inflammatory indices, as well as significantly decreased expression of tight junction-associated proteins. In addition, the DSS group showed significantly increased apoptotic cell numbers,and showed significantly increased M1 macrophages in spleen and colon tissues.They also showed significantly decreased M2 macrophages in colon tissues, as well as activation of the PI3K/AKT signaling pathway(all P < 0.05). Compared with rats in the DSS group, rats in the DSS + PNS group showed significantly lengthened colon lengths, decreased disease activity indices, and significantly alleviated oxidative stress reactions and inflammatory responses. In addition, this group showed significantly increased expression of tight junction-associated proteins, significantly decreased apoptotic cell numbers, and significantly decreased M1 macrophages in spleen and colon tissues. This group further showed significantly increased M2 macrophages in colon tissues, and significantly suppressed activation of the PI3K/AKT signaling pathway, as well as a dose dependency(all P < 0.05). When the PI3K/AKT signaling pathway was inhibited, the apoptosis rate of colon tissue cells in the DSS + LY294002 group was significantly lower than that of the DSS group(P < 0.05).CONCLUSION PNS can protect rats against DSS-induced intestinal inflammatory injury by inhibiting the PI3K/AKT signaling pathway, and therefore may be potentially used in the future as a drug for colitis.
基金Supported by Instituto de Salud Carlos Ⅲ (C03/02), FEDER funds, Fundación Canaria de Investigación (PI 21/02), and Spanish Ministry of Education to CM (EX2004-0396)
文摘AIM: To study whether matrix metalloproteinase-9 (MMP-9) is a key factor in epithelial damage in the dextran sodium sulphate (DSS) model of colitis in mice.METHODS: MMP-9-deficient and wild-type (wt) mice were given 5% DSS in drinking water for 5 d followed by recovery up to 7 d. On d 5 and 12 after induction of colitis, gelatinases, MMP-2 and MMP-9, were measured in homogenates of colonic tissue by zymography and Western blot, whereas tissue inhibitor of metalloproteinases (TIMPs) were measured by reverse zymography. The gelatinolytic activity was also determined in supernatants of polymorphonuclear leukocytes (PMN) isolated from mice blood. Moreover, intestinal epithelial cells were stimulated with TNF-α to study whether these cells were able to produce MMPs. Finally, colonic mucosal lesions were measured by microscopic examination. RESULTS: On d 5 of colitis, the activity of MMP-9 was increased in homogenates of colonic tissues (0.24 ± 0.1 vs 21.3 ± 6.4, P < 0.05) and PMN from peripheral blood in wt (0.5 ± 0.1 vs 10.4 ± 0.7, P < 0.05), but not in MMP-9-deficient animals. The MMP-9 activity was also up-regulated by TNF-α in epithelial intestinal cells (2.5 ± 0.5 vs 14.7 ± 3.0, P < 0.05). Although colitis also led to increase of TIMP-1 activity, the MMP-9/TIMP-1 balance remained elevated. Finally, in the MMP-9-deficient colitic mice both the extent and severity of intestinal epithelialinjury were significantly attenuated when compared with wt mice. CONCLUSION: We conclude that DSS induced colitis is markedly attenuated in animals lacking MMP-9. This suggests that intestinal injury induced by DSS is modu-lated by MMP-9 and that inhibition of this gelatinase may reduce inflammation.
