Colitis Tissue Research Articles

Secoisolariciresinol diglucoside suppresses Dextran sulfate sodium salt-induced colitis through inhibiting NLRP1 inflammasome

Inflammatory bowel disease (IBD) is a chronic and recurrent intestinal inflammatory disease with high risks for colorectal cancer and extremely affect people's health. Secoisolariciresinol diglucoside (SDG), a major component of lignans, exerts anti-inflammatory effects against digestive system diseases through a multi-target mechanism. However, the effect of SDG on IBD is not clear. In the present study, we aimed to investigate the effects of SDG on IBD and elucidate the underlying mechanism. The Dextran Sulfate Sodium Salt (DSS)-induced colitis model and lipopolysaccharide (LPS) stimulated RAW264.7 mouse macrophages cellular inflammation model were established. Morphological and pathological changes in colitis tissue in mice were observed by HE staining. Macrophage infiltration was detected by flow cytometry. The levels of nucleotide oligomerization domain-like receptor protein 1 (NLRP1) inflammasome complexes, nuclear factor-kappa B (NF-κB) and inflammatory cytokines were determined using quantitative real-time polymerase chain reaction, western blotting, and enzyme-linked immunosorbent assay. The results showed that SDG significantly attenuated the pathological severity and the number of macrophage infiltration of colitis in mice. Besides, SDG decreased the levels of inflammatory cytokines (IL-1β, IL-18 and TNF-α) and inhibited the activation of the NLRP1 inflammasome in DSS-induced colitis mice and RAW264.7 mouse macrophages. Moreover, the inhibitory effect of SDG was partly dependent on the disruption of NF-κB activation. Our results indicated that SDG relieves colitis by inhibiting NLRP1 inflammasome, and partly dependent on the disruption of NF-κB activation. Therefore, SDG may be a potential treatment option for IBD.

NEK7 interacts with NLRP3 to modulate the pyroptosis in inflammatory bowel disease via NF-\u03baB signaling

Inflammatory bowel disease (IBD) is one of the most common diseases in the gastrointestinal tract related to aberrant inflammation. Pyroptosis, which is characterized by inflammasome formation, the activation of caspase-1, and the separation of the N- and C-terminals of GSDMD, might be related to IBD pathogenesis. NEK7 is an important component of the NLRP3 inflammasome in macrophages. We attempted to investigate the mechanism of NEK7 interacting with NLRP3 to modulate the pyroptosis in IBD. NEK7 mRNA and protein expression and pyroptosis-associated factors, including Caspase-1 (p45, p20), NLRP3, and GSDMD, were upregulated in IBD tissues. NEK7 knockdown abolish ATP + LPS-induced pyroptosis in vitro and improved DSS-induced chronic colitis in vivo. NEK7 interacted with NLRP3, as revealed by Co-IP and GST pull-down assays, to exert its effects. Moreover, short-term LPS treatment alone induced no significant changes in NEK7 protein level. TLR4/NF-κB signaling in MODE-K cells could be activated by LPS treatment. LPS-induced NEK7 upregulation could be significantly reversed by JSH-23, an inhibitor of p65. Furthermore, LUC and ChIP assays revealed that RELA might activate the transcription of NEK7 via targeting its promoter region. LPS-induced TLR4/NF-κB activation causes an increase in NEK7 expression by RELA binding NEK7 promoter region. In conclusion, NEK7 interacts with NLRP3 to modulate NLRP3 inflammasome activation, therefore modulating the pyroptosis in MODE-K cells and DSS-induced chronic colitis in mice. We provide a novel mechanism of NEK7-NLRP3 interaction affecting IBD via pyroptosis.

Antibody responses to influenza vaccine in patients on biological therapy: Results of RIER cohort study

Background and objectivesInfluenza vaccine is recommended for patients with autoimmune inflammatory rheumatic diseases who receive biological therapy. To evaluate if biological therapy impairs immunization after seasonal influenza vaccine. Material and methodsPatients with inflammatory arthopathies, psoriasis, inflammatory bowel disease or connective tissue diseases who were receiving or were going to initiate biological therapy were included and vaccinated during 2014–2015 influenza season. ELISA was used to measure influenza antigen A and B antibodies, before and after vaccination. Demographic parameters, diagnosis and kind of treatment were recorded and their influence on the final serological status against influenza was studied. Results253 subjects were analyzed. After vaccination, 77% of participants presented detectable antibodies against antigen A and 50.6% of them had detectable antibodies against antigen B. Final seropositivity rate against antigen B antibodies increased from baseline (50.6% vs 43.5%, p<0.001). Anti-TNF drugs were associated with better response and rituximab with the worst (79.2% vs 55.0% for final seropositivity against antigen A, p=0.020). Vaccine response in the rituximab group tended to improve when the interval between the drug administration and the vaccination was at least 12 weeks (seropositivity rate 80.0% in those with the longer interval vs 25.0% in the other group, p=0.054). ConclusionsAmong the patients on biological therapy vaccinated against influenza, anti-TNF therapy was identified as a predictive factor of final seropositivity. Rituximab presented a lower rate of final seropositivity, which could be increased with an accurate administration schedule.

Induction of Inflammatory Macrophages in the Gut and Extra-Gut Tissues by Colitis-Mediated Escherichia coli.

SummaryInflammatory macrophages play a critical role in gut and extra-gut inflammatory disorders, which may be promoted through the dysbiosis of gut microbiota. However, it is poorly understood how gut microbiota affect inflammatory macrophages. Here, we found that increased Escherichia coli (E. coli) in inflamed colon may induce inflammatory macrophages in gut and extra-gut tissues. These E. coli are different from other commensal and pathogenic E. coli in genomic components and also in ability to induce inflammatory responses. Dominant E. coli from colitic tissues induce gut inflammatory macrophages through a regulating network consisted of IL-18, IFN-γ, IL-12, and IL-22 in gut tissues. These E. coli also directly activate macrophages. Cytosolic inflammasome components PCKδ, NLRC4, caspase8, and caspase1/11 are involved in E. coli-mediated activation in both gut epithelial cells and macrophages. These disclose a novel mechanism for how dysbiosis of gut microbiota in colitis cause inflammatory macrophages related to multiple diseases.

1619 Not All Intra-Peritoneal Free Air Is Created Equal. Pneumatosis Cystoides Intestinalis Causing Massive Pneumoperitoneum After a Colonoscopy, a Benign Finding

INTRODUCTION: Pneumoperitoneum is the presence of free air in the peritoneal cavity. Visceral perforation, obstruction, and infection are the most ominous causes and usually present with signs of acute peritonitis requiring emergent surgery. CASE DESCRIPTION/METHODS: A 60-year-old man was found to have extensive colonic wall bullae (pneumatosis coli) in the transverse colon during a colonoscopy (Figure 1). Contrast-enhanced abdominal computed tomography (CT) 6 days later detected free air in the peritoneal cavity, the umbilical subcutaneous fat, and pneumatosis intestinalis in the distal transverse colon (Figure 2). Patient reported mild abdominal distension which quickly improved, otherwise he was asymptomatic. His abdomen was distended, but benign with no signs of peritoneal irritation. His laboratory work was unremarkable with normal white blood cell count and lactic acid. He was managed conservatively with nothing by mouth, intravenous fluids and systemic antibiotic therapy. He completed a 10-day course of antibiotics at home. A CT abdomen 2 months later showed complete resolution of the pneumoperitoneum (Figure 3). DISCUSSION: Prompt diagnosis of pneumoperitoneum and its cause is crucial, and it may require timely surgical intervention. However, there are causes of pneumoperitoneum that do not require surgery; these cases must be readily distinguished. One of the etiologies of asymptomatic pneumoperitoneum is rupture of the sub-serosal cysts present in the colonic wall of patients with idiopathic pneumatosis cystoides intestinalis. Primary pneumatosis intestinalis (15% of cases) is a benign idiopathic condition in which thin-walled cysts develop in the submucosa or subserosa of the colon. The secondary form (85% of cases) is associated with obstructive pulmonary disease, as well as with obstructive and necrotic gastrointestinal disease, infection, inflammatory bowel disease, medication-induced (chemotherapy and steroid), autoimmune disease, immunosuppression, and connective tissue disorders. In conclusion, intraperitoneal air is not always related to life-threatening conditions e.g. visceral perforation requiring invasive interventions; sometimes it is related to benign causes, one of them which we mentioned in our case. Therefore, the correlation should be made with the clinical presentation, frequent abdominal exams, imaging findings, and laboratory tests to prevent unnecessary interventions.

A qualitative transcriptional signature for the early diagnosis of colorectal cancer.

Currently, using biopsy specimens for the early diagnosis of colorectal cancer (CRC) is not entirely reliable due to insufficient sampling amount and inaccurate sampling location. Thus, it is necessary to develop a signature that can accurately identify patients with CRC under these clinical scenarios. Based on the relative expression orderings of genes within individual samples, we developed a qualitative transcriptional signature to discriminate CRC tissues, including CRC adjacent normal tissues from non‐CRC individuals. The signature was validated using multiple microarray and RNA sequencing data from different sources. In the training data, a signature consisting of 7 gene pairs was identified. It was well validated in both biopsy and surgical resection specimens from multiple datasets measured by different platforms. For biopsy specimens, 97.6% of 42 CRC tissues and 94.5% of 163 non‐CRC (normal or inflammatory bowel disease) tissues were correctly classified. For surgically resected specimens, 99.5% of 854 CRC tissues and 96.3% of 81 CRC adjacent normal tissues were correctly identified as CRC. Notably, we additionally measured 33 CRC biopsy specimens by the Affymetrix platform and 13 CRC surgical resection specimens, with different proportions of tumor epithelial cells, ranging from 40% to 100%, by the RNA sequencing platform, and all these samples were correctly identified as CRC. The signature can be used for the early diagnosis of CRC, which is also suitable for minimum biopsy specimens and inaccurately sampled specimens, and thus has potential value for clinical application.

Profiling the lncRNA-miRNA-mRNA ceRNA network to reveal potential crosstalk between inflammatory bowel disease and colorectal cancer

BackgroundBecause of the increasing dysplasia rate in the lifelong course of inflammatory bowel disease (IBD) patients, it is imperative to characterize the crosstalk between IBD and colorectal cancer (CRC). However, there have been no reports revealing the occurrence of the ceRNA network in IBD-related CRC.MethodsIn this study, we conducted gene expression profile studies of databases and performed an integrated analysis to detect the potential of lncRNA-miRNA-mRNA ceRNA in regulating disease transformation. R packages were used to screen differentially expressed mRNA, lncRNA and miRNA among CRC, IBD and normal tissue. The lncRNA-miRNA-mRNA network was constructed based on predicted miRNA-targeted lncRNAs and miRNA-targeted mRNAs. Functional analyses were then conducted to identify genes involved in the ceRNA network, and key lncRNAs were evaluated based on several clinical outcomes.ResultsA total of three lncRNAs, 15 miRNAs, and 138 mRNAs were identified as potential mediators in the pathophysiological processes of IBD-related CRC. Gene Ontology annotation enrichment analysis confirmed that the dysplasia process was strongly associated with immune response, response to lipopolysaccharide, and inflammatory response. Survival analysis showed that LINC01106 (HR = 1.7; p < 0.05) were strongly associated with overall survival of colorectal cancer patients. The current study identified a series of IBD-related mRNAs, miRNA, and lncRNAs, and highlighted the important role of ceRNAs in the pathogenesis of IBD-related CRC. Among them, the LINC01106-miRNA-mRNA axis was identified as vital targets for further research.

Long non-coding RNA CRNDE promotes cell apoptosis by suppressing miR-495 in inflammatory bowel disease

ObjectiveThis article aims to investigate the mechanism of microRNA-495 (miR-495) and long non-coding RNA CRNDE on the apoptosis of colonic epithelial cells in inflammatory bowel diseases (IBDs). MethodsThe mouse model of IBD was induced by dextran sulfate sodium (DSS), and human colonic epithelial cell lines (HT-29, LOVO, and Caco-2) were treated with DSS, and received cell transfection. RNA interference was used to down-regulate CRNDE expression. ResultsCRNDE and SOCS1 were highly expressed, but miR-495 was lowly expressed in the DSS-induced colitis tissues and colonic epithelial cell lines. Interference of CRNDE inhibited cell apoptosis of DSS-induced colonic epithelial cells. The interaction between CRNDE and miR-495 was confirmed by RNA immunoprecipitation and RNA pull-down assay. The target relationship between miR-495 and SOCS1 was confirmed by the luciferase reporter assay. CRNDE promoted DSS-induced colonic epithelial cell apoptosis via miR-495/SOCS1. CRNDE interference in DSS-induced colitis mouse model alleviated clinical manifestations of IBD. ConclusionsOur findings demonstrated that CRNDE promoted DSS-induced colonic epithelial cell apoptosis via suppressing miR-495 and increasing SOCS1, indicating CRNDE as a novel target of treating IBD.

Oral Targeted Delivery by Nanoparticles Enhances Efficacy of an Hsp90 Inhibitor by Reducing Systemic Exposure in Murine Models of Colitis and Colitis-Associated Cancer.

Heat shock protein 90 [Hsp90]-targeted therapy has been proposed as a promising strategy for the treatment of ulcerative colitis [UC] and colitis-associated cancer [CAC]. Systemic administration of the Hsp90 inhibitor, 17-AAG, was found to be profoundly protective in preclinical mouse models of inflammatory bowel disease [IBD]. However, the therapeutic potential of 17-AAG is limited by potential side effects associated with its systemic exposure and the modest bioavailability afforded by its oral administration. To address these issues, we used a versatile single-step surface-functionalizing technique to prepare a 17-AAG oral delivery system using PLGA/PLA-PEG-FA nanoparticles [NP-PEG-FA/17-AAG]. NP-PEG-FA could be efficiently taken up by mouse Colon-26 cells and activated Raw 264.7 cells in vitro and by inflamed mouse colitis tissues in vivo. The therapeutic efficacy of orally administrated NP-PEG-FA/17-AAG was evaluated in in vivo models using dextran sulphate sodium [DSS]-induced UC and azoxymethane [AOM]/DSS-induced CAC, and the results indicated that NP-PEG-FA/17-AAG significantly alleviated the symptoms of UC and CAC. More importantly, our inflamed colitis-targeted 17-AAG nano-formulation reduced systemic exposure and provided a degree of therapeutic response similar to that obtained by systemic administration [intraperitoneal] of 17-AAG, but at a ten-fold lower dose. We describe a convenient, orally administrated 17-AAG delivery system that exhibits enhanced efficacy in UC and CAC therapy while reducing systemic exposure. This system may represent a promising therapeutic approach for treating UC and CAC.

RICK/RIP2 is a NOD2-independent nodal point of gut inflammation.

Previous studies have shown that inhibition of receptor-interacting serine/threonine kinase (RICK) (also known as RIP2) results in amelioration of experimental colitis. This role has largely been attributed to nucleotide-binding oligomerization domain 2 (NOD2) signaling since the latter is considered a major inducer of RICK activation. In this study, we explored the molecular mechanisms accounting for RICK-mediated inhibition of inflammatory bowel disease (IBD). In an initial series of studies focused on trinitrobenzene sulfonic acid (TNBS)-colitis and dextran sodium sulfate (DSS)-colitis we showed that down-regulation of intestinal RICK expression in NOD2-intact mice by intra-rectal administration of a plasmid expressing RICK-specific siRNA was accompanied by down-regulation of pro-inflammatory cytokine responses in the colon and protection of the mice from experimental colitis. Somewhat surprisingly, intra-rectal administration of RICK-siRNA also inhibited TNBS-colitis and DSS-colitis in NOD2-deficient and in NOD1/NOD2-double deficient mice. In complementary studies of humans with IBD we found that expression of RICK, cellular inhibitor of apoptosis protein 2 (cIAP2) and downstream signaling partners were markedly increased in inflamed tissue of IBD compared to controls without marked elevations of NOD1 or NOD2 expression. In addition, the increase in RICK expression correlated with disease activity and pro-inflammatory cytokine responses. These studies thus suggest that NOD1- or NOD2-independenent activation of RICK plays a major role in both murine experimental colitis and human IBD.

Antibody responses to influenza vaccine in patients on biological therapy: Results of RIER cohort study

Background and objectivesInfluenza vaccine is recommended for patients with autoimmune inflammatory rheumatic diseases who receive biological therapy. To evaluate if biological therapy impairs immunization after seasonal influenza vaccine. Material and methodsPatients with inflammatory arthopathies, psoriasis, inflammatory bowel disease or connective tissue diseases who were receiving or were going to initiate biological therapy were included and vaccinated during 2014–2015 influenza season. ELISA was used to measure influenza antigen A and B antibodies, before and after vaccination. Demographic parameters, diagnosis and kind of treatment were recorded and their influence on the final serological status against influenza was studied. Results253 subjects were analyzed. After vaccination, 77% of participants presented detectable antibodies against antigen A and 50.6% of them had detectable antibodies against antigen B. Final seropositivity rate against antigen B antibodies increased from baseline (50.6% vs 43.5%, p<0.001). Anti-TNF drugs were associated with better response and rituximab with the worst (79.2% vs 55.0% for final seropositivity against antigen A, p=0.020). Vaccine response in the rituximab group tended to improve when the interval between the drug administration and the vaccination was at least 12 weeks (seropositivity rate 80.0% in those with the longer interval vs 25.0% in the other group, p=0.054). ConclusionsAmong the patients on biological therapy vaccinated against influenza, anti-TNF therapy was identified as a predictive factor of final seropositivity. Rituximab presented a lower rate of final seropositivity, which could be increased with an accurate administration schedule.

Increased Risk of Autoimmune Disorders in 21-Hydroxylase Deficiency: A Swedish Population-Based National Cohort Study.

ContextThe prevalence of autoimmune disorders in individuals with 21-hydroxylase deficiency (21OHD) is unclear. The gene responsible, CYP21A2, is located in a highly immunologically active region.ObjectiveTo study the prevalence of autoimmune disorders in individuals with 21OHD.Design, Setting, and ParticipantsPatients with 21OHD (n = 714) were compared with controls matched for sex, year, and place of birth (n = 71,400). Data were derived by linking National Population-Based Registers. Subgroup analyses were performed regarding phenotype and CYP21A2 genotype.Main Outcome MeasuresNumber and type of autoimmune disorders.ResultsMean age (± SD) was 29.8 ± 18.4 years. Individuals with 21OHD had more autoimmune disorders than did controls [7.4% vs 5.1%, P < 0.01; relative risk (RR) 1.47 (95% CI, 1.13 to 1.91)], especially male patients [6.8% vs 4.1%, P < 0.05; RR, 1.64 (95% CI, 1.08 to 2.49)], whereas it did not reach significance for female patients [7.9% vs 5.8%, P = 0.068; RR, 1.37 (95% CI, 0.98 to 1.92)]. Among the specific autoimmune groups and disorders, autoimmune endocrine disorders and autoimmune thyroid disorders, including Graves disease, were significantly increased in the entire cohort of patients and for male and female patients separately. Inflammatory bowel disease (IBD) and systemic connective tissue disorders did not reach significant levels for the entire cohort (P = 0.075 and 0.05, respectively), but male patients were more affected by IBD (P = 0.022). The groups with milder phenotypes and genotypes seemed to be more affected by autoimmune disorders.Conclusions21OHD was associated with an increased prevalence of autoimmune disorders. The relatively young age of the patient cohort and possible protective effects by glucocorticoid treatment may have underestimated the risk.

Decursinol Angelate Ameliorates Dextran Sodium Sulfate-Induced Colitis by Modulating Type 17 Helper T Cell Responses.

Angelica gigas has been used as a Korean traditional medicine for pain relief and gynecological health. Although the extracts are reported to have an anti-inflammatory property, the bioactive compounds of the herbal plant and the effect on T cell responses are unclear. In this study, we identified decursinol angelate (DA) as an immunomodulatory ingredient of A. gigas and demonstrated its suppressive effect on type 17 helper T (Th17) cell responses. Helper T cell culture experiments revealed that DA impeded the differentiation of Th17 cells and IL-17 production without affecting the survival and proliferation of CD4 T cells. By using a dextran sodium sulfate (DSS)-induced colitis model, we determined the therapeutic potential of DA for the treatment of ulcerative colitis. DA treatment attenuated the severity of colitis including a reduction in weight loss, colon shortening, and protection from colonic tissue damage induced by DSS administration. Intriguingly, Th17 cells concurrently with neutrophils in the colitis tissues were significantly decreased by the DA treatment. Overall, our experimental evidence reveals for the first time that DA is an anti-inflammatory compound to modulate inflammatory T cells, and suggests DA as a potential therapeutic agent to manage inflammatory conditions associated with Th17 cell responses.

Chemopreventive Activity of Red Ginseng Oil in a Mouse Model of Azoxymethane/Dextran Sulfate Sodium-Induced Inflammation-Associated Colon Carcinogenesis.

Our previous studies have demonstrated antioxidant and cytoprotective properties of red ginseng oil (RGO). However, the role of RGO in models of intestinal inflammation has not been elucidated. In this study, we evaluated the chemopreventive effect of RGO in a mouse model of azoxymethane/dextran sulfate sodium (AOM/DSS)-induced colitis and explored its underlying mechanisms. Male C57BL/6 mice were intraperitoneally injected with a single dose of AOM (10 mg/kg), followed by 1.5% DSS in drinking water for 7 days to produce colon carcinogenesis. RGO at 10 or 100 mg/kg was orally given for 17 weeks. RGO supplementation reduced the plasma nitric oxide (NO) concentration as well as lipid peroxidation and inhibited the production of proinflammatory factors such as inducible NO synthase, cyclooxygenase-2, interleukin 1β, IL-6, and tumor necrosis factor-α in the mouse colitis tissue. Increased phosphorylation levels of p65 and IκB by AOM/DSS exposure were attenuated by the presence of RGO. In addition, RGO supplementation induced the activity of primary antioxidant enzymes such as superoxide dismutase and catalase as well as the expression of nuclear factor erythroid 2-related factor 2-mediated antioxidant enzyme hemeoxygenase-1 in the colons of AOM/DSS-treated mice. These findings indicate that RGO may be a potent natural chemopreventive agent for ameliorating inflammatory bowel diseases.

Reduced CD27-IgD- B Cells in Blood and Raised CD27-IgD- B Cells in Gut-Associated Lymphoid Tissue in Inflammatory Bowel Disease.

The intestinal mucosa in inflammatory bowel disease (IBD) contains increased frequencies of lymphocytes and a disproportionate increase in plasma cells secreting immunoglobulin (Ig)G relative to other isotypes compared to healthy controls. Despite consistent evidence of B lineage cells in the mucosa in IBD, little is known of B cell recruitment to the gut in IBD. Here we analyzed B cells in blood of patients with Crohn's disease (CD) and ulcerative colitis (UC) with a range of disease activities. We analyzed the frequencies of known B cell subsets in blood and observed a consistent reduction in the proportion of CD27−IgD− B cells expressing all Ig isotypes in the blood in IBD (independent of severity of disease and treatment) compared to healthy controls. Successful treatment of patients with biologic therapies did not change the profile of B cell subsets in blood. By mass cytometry we demonstrated that CD27−IgD− B cells were proportionately enriched in the gut-associated lymphoid tissue (GALT) in IBD. Since production of TNFα is a feature of IBD relevant to therapies, we sought to determine whether B cells in GALT or the CD27−IgD− subset in particular could contribute to pathology by secretion of TNFα or IL-10. We found that donor matched GALT and blood B cells are capable of producing TNFα as well as IL-10, but we saw no evidence that CD27−IgD− B cells from blood expressed more TNFα compared to other subsets. The reduced proportion of CD27−IgD− B cells in blood and the increased proportion in the gut implies that CD27−IgD− B cells are recruited from the blood to the gut in IBD. CD27−IgD− B cells have been implicated in immune responses to intestinal bacteria and recruitment to GALT, and may contribute to the intestinal inflammatory milieu in IBD.

CCAT1 lncRNA Promotes Inflammatory Bowel Disease Malignancy by Destroying Intestinal Barrier via Downregulating miR-185-3p.

The long noncoding RNA (lncRNA) colon cancer-associated transcript-1 (CCAT1) has been reported to play a vital role in the development of cancer. Although the link between inflammation and cancer initiation is well established, whether CCAT1 is involved in inflammation and promotes inflammatory bowel disease (IBD) malignancy remains undetermined. We aimed to investigate the expression of CCAT1 in IBD and the effect of CCAT1 overexpression on intestinal epithelial barrier function. The relationship between CCAT1 and the inflammation-related pathway was analyzed in both colorectal cancer (CRC) and IBD patients. Gene expression was detected by real-time polymerase chain reaction and Western blot. Transepithelial electrical resistance (TEER) and FD-4 flux measurement were used to test the effect of CCAT1 and miR-185-3p on intestinal epithelial barrier function. Luciferase assay was performed to validate the target site of miR-185-3p on 3'-UTR of MLCK mRNA. Gene set enrichment analysis revealed that several inflammation-related genes were enriched in the CCAT1 high-expressed group of CRC patients. The relationship between CCAT1 and inflammation activation in IBD patients was further confirmed. CCAT1 expression positively correlated with MLCK, which acts as a protein kinase to phosphorylate myosin light chain and induces tight junction protein distribution, whereas it was negatively correlated with miR-185-3p in IBD tissues. We also determined that CCAT1 overexpression increased Caco-2 monolayer permeability and upregulated MLCK. Furthermore, CCAT1-induced MLCK overexpression and IBD disease progression were significantly attenuated by miR-185-3p. The CCAT1/miR-185-3p/MLCK signaling pathway is strongly activated to destroy barrier function and promotes the pathogenesis of IBD.

Oral administration of colitis tissue-accumulating porous nanoparticles for ulcerative colitis therapy

To improve the penetration and accumulation of anti-inflammatory drugs in colitis tissue, we functionalized the surface of porous poly(lactic-co-glycolic acid) nanoparticles (NPs) using pluronic F127 (PF127) and loaded curcumin (CUR) into the resulting NPs to obtain porous PF127-functionalized CUR-loaded NPs (porous PF127-NPs). These NPs had an average hydrodynamic diameter of about 270 nm with a highly monodisperse size distribution, slightly negative surface charge and controllable CUR release profile. It was found that they had good biocompatibility and yielded a much higher cellular uptake rate of CUR than porous CUR-loaded NPs without PF127 modification (porous NPs). In addition, porous PF127-NPs showed a greater capacity to inhibit the major pro-inflammatory cytokines (IL-6, IL-12 and TNF-α) secreted from lipopolysaccharide-activated macrophages than porous NPs and non-porous PF127-NPs. In vivo experiments suggested that porous PF127-NPs achieved the best therapeutic outcomes against ulcerative colitis (UC) in mice compared with porous NPs and non-porous PF127-NPs. Our results clearly demonstrate that these fabricated porous PF127-NPs show a great promise as an efficient CUR nanocarrier for UC therapy.

Combination therapy of mesenchymal stromal cells and sulfasalazine attenuates trinitrobenzene sulfonic acid induced colitis in the rat: The S1P pathway.

Adipose derived mesenchymal stem cells (ASCs) transplantation is a novel immunomodulatory therapeutic tool to ameliorate the symptom of inflammatory bowel disease (IBD). The objective of this study was to investigate the therapeutic effects of combined sufasalazine and ASCs therapy in a rat model of IBD. After induction of colitis in rats, ASCs were cultured and intraperitoneally injected (3 × 106 cells/kg) into the rats on Days 1 and 5 after inducing colitis, in conjunction with daily oral administration of low dose of sulfasalazine (30 mg/kg). The regenerative effects of combination of ASCs and sulfasalazine on ulcerative colitis were assessed by measuring body weight, colonic weight/length ratio, disease activity index, macroscopic scores, histopathological examinations, cytokine, and inflammation markers profiles. In addition, western blot analysis was used to assess the levels of nuclear factor-kappa B (NF-κB) and apoptosis related proteins in colitis tissues. Simultaneous treatment with ASCs and sulfasalazine was associated with significant amelioration of disease activity index, macroscopic and microscopic colitis scores, as well as inhibition of the proinflammatory cytokines in trinitrobenzene sulfonic acid (TNBS)-induced colitis. Moreover, combined ASCs and sulfasalazine therapy effectively inhibited the NF-κB signaling pathway, reduced the expression of Bax and prevented the loss of Bcl-2 proteins in colon tissue of the rats with TNBS-induced colitis. Furthermore, combined treatment with ASCs and sulfasalazine shifted inflammatory M1 to anti-inflammatory M2 macrophages by decreasing the levels of MCP1, CXCL9 and increasing IL-10, Arg-1 levels. In conclusion, combination of ASCs with conventional IBD therapy is potentially a much more powerful strategy to slow the progression of colitis via reducing inflammatory and apoptotic markers than either therapy alone.

EW-7197 prevents ulcerative colitis-associated fibrosis and inflammation.

EW-7197 is a transforming growth factor-β type I receptor kinase inhibitor with potential anti-inflammatory and antifibrotic properties. Here, we investigate the potential therapeutic effects of EW-7197 in a murine model of ulcerative colitis. EW-7197 attenuated the colitis disease activity index by improving rectal bleeding, body weight, and degree of stool consistency. EW-7197 also reduced colorectal tissue damage and the colon histopathological score by reducing crypt loss, mucosal damage, and tissue inflammation. Moreover, EW-7197 appeared to ameliorate the inflammatory and fibrotic responses by reducing oxidative stress, reducing submucosal edema and inflammatory cell infiltration, downregulating proinflammatory and pro-fibrotic genes, and inhibiting excessive collagen deposition in inflamed and fibrotic ulcerative colitis tissues. These results suggest that EW-7197 has potentially useful therapeutic properties against colitis, with clinically translational potential of inhibiting key pathological responses of inflammation and fibrosis in patients with colitis.

MicroRNA 429 regulates the expression of CHMP5 in the inflammatory colitis and colorectal cancer cells.

MicroRNAs (miRNAs) play an important role in the pathogenesis of human diseases by regulating the expression of target genes in specific cells or tissues. In this study, we analyzed the association between the MIR429 and its target gene, charged multivesicular body protein 5 (CHMP5), in human colon cancer cells and in a DSS-induced colitis mouse model. A luciferase reporter system was used to confirm the effect of MIR429 on CHMP5 expression. Protein or mRNA expression of the target gene and associated molecules were measured by Western blot or quantitative RT-PCR (qRT-PCR), respectively. Flow cytometry was used to compare cell viability or cell cycle progression. CHMP5 mRNA and protein expression was directly down-regulated by MIR429. We found that MIR429 inhibited colon cancer cell growth and cell cycle progression, and CHMP5 was overexpressed in the DSS-induced colitis mouse model and human ulcerative colitis (UC) tissues. Our findings show that CHMP5 is a direct target of MIR429 in human colon cancer cell lines and suggest that CHMP5 up-regulation as a result of reduced MIR429 expression in DSS-induced mice colitis tissues and human UC tissues may restrict apoptosis and promote cell proliferation.