Construction of the underlying circRNA-miRNA-mRNA regulatory network and a new diagnostic model in ulcerative colitis by bioinformatics analysis.

BACKGROUND: Circular RNAs (circRNAs) are involved in the pathogenesis of many diseases through competing endogenous RNA (ceRNA) regulatory mechanisms. AIM: To investigate a circRNA-related ceRNA regulatory network and a new predictive model by circRNA to understand the diagnostic mechanism of circRNAs in ulcerative colitis (UC). METHODS: We obtained gene expression profiles of circRNAs, miRNAs, and mRNAs in UC from the Gene Expression Omnibus dataset. The circRNA-miRNA-mRNA network was constructed based on circRNA-miRNA and miRNA-mRNA interactions. Functional enrichment analysis was performed to identify the biological mechanisms involved in circRNAs. We identified the most relevant differential circRNAs for diagnosing UC and constructed a new predictive nomogram, whose efficacy was tested with the C-index, receiver operating characteristic curve (ROC), and decision curve analysis (DCA). RESULTS: A circRNA-miRNA-mRNA regulatory network was obtained, containing 12 circRNAs, three miRNAs, and 38 mRNAs. Two optimal prognostic-related differentially expressed circRNAs, hsa_circ_0085323 and hsa_circ_0036906, were included to construct a predictive nomogram. The model showed good discrimination, with a C-index of 1(> 0.9, high accuracy). ROC and DCA suggested that the nomogram had a beneficial diagnostic ability. CONCLUSION: This novel predictive nomogram incorporating hsa_circ_0085323 and hsa_circ_0036906 can be conveniently used to predict the risk of UC. The circRNa-miRNA-mRNA network in UC could be more clinically significant.

JMJD3/H3K27me3 epigenetic modification regulates Th17/Treg cell differentiation in ulcerative colitis.

Ulcerative colitis (UC) is a chronic nonspecific inflammatory bowel disease characterized by chronic inflammation and ulceration of the colonic mucosa, frequent relapse, and cancerization that is difficult to cure. In recent years, the incidence of UC has increased. However, its etiology and pathogenesis are still not completely clear. In this study, dextran sodium sulfate (DSS) was used to induce the model, and GSK-J1 and dexamethasone were administered to the mice. A variety of molecular biology and immunological techniques, such as immunofluorescence, PCR and chromatin immunoprecipitation (ChIP), were used to examine JMJD3/H3K27me3-mediated regulation of Th17/Treg cell differentiation in UC by targeting histone modification. This study will provide an important theoretical basis for understanding the pathogenesis and potential therapeutic targets of UC.

Compound sophorae decoction enhances intestinal barrier function of dextran sodium sulfate induced colitis via regulating notch signaling pathway in mice.

BACKGROUND: Compound sophorae decoction (CSD), a Chinese Herbal decoction, is frequently clinically prescribed for patients suffered from ulcerative colitis (UC) characterized by bloody diarrhea. Yet, the underlying mechanism about how this formulae works is remain elusive. METHODS: In the present study, the experimental colitis in C57BL/6 J mice was induced by oral administration of standard diets containing 3% dextran sodium sulfate (DSS), and CSD was given orally for treatment at the same time. The clinical symptoms including stool and body weight were recorded each day, and colon length and its histopathological changes were observed. Apoptosis of colonic epithelium was studied by detecting protein expression of cleaved caspase-3, and cell proliferation by Ki-67 immunohistochemistry. Tight junction complex like ZO-1 and occludin were also determined by transmission electron microscope and immunofluorescence. The concentration of FITC-dextran 4000 was measured to evaluate intestinal barrier permeability and possible signaling pathway was investigated. Mucin2 (MUC2) and notch pathway were tested through western blot. The M1/M2 ratio in spleen and mesenteric lymph nodes were detected by flow cytometry. And the mRNA levels of iNOS and Arg1 were examined by qRT-PCR. RESULTS: CSD could significantly alleviate the clinical manifestations and pathological damage. Body weight loss and DAI score of mice with colitis were improved and shortening of colon was inhibited. The administration of CSD was able to reduce apoptotic epithelial cells and facilitate epithelial cell regeneration. Increased intestinal permeability was reduced in DSS-induced colitis mice. In addition, CSD treatment obviously up-regulated the expression of ZO-1 and occludin and the secretion of MUC2, regulated notch signaling, and decreased the ratio of M1/M2. CONCLUSIONS: These data together suggest that CSD can effectively mitigate intestinal inflammation, promote phenotypic change in macrophage phenotype and enhance colonic mucosal barrier function by, at least in part, regulating notch signaling in mice affected by DSS-induced colitis.

Autotaxin-Lysophosphatidic Acid Axis Blockade Improves Inflammation by Regulating Th17 Cell Differentiation in DSS-Induced Chronic Colitis Mice.

Autotaxin-lysophosphatidic acid (ATX-LPA) axis is closely associated with several inflammation-related diseases. In the colonic mucosa of patients with chronic ulcerative colitis (UC), the expression of ATX and the percentage of Th17 cells are found to increase. However, it is unclear whether ATX-LPA axis affects the differentiation of Th17 cells in chronic UC. To investigate whether ATX-LPA axis contributes to Th17 cell differentiation, a mouse model of chronic UC was established by drinking water with DSS at intervals. ATX inhibitor was used as an intervention. The disease active index (DAI), colonic weight to length ratio, colon length, colon histopathology, and MAdCAM-1 were observed. Additionally, the expression of ATX, LPA receptor, CD34, IL-17A, IL-21, IL-6, ROR-γt, STAT3 in colonic tissue, and the percentage of Th17 cells in spleens and mesenteric lymph nodes (MLNs) were measured using different methods. ATX blockade was able to relieve symptoms and inflammatory response of DSS-induced chronic colitis. The DAI and colonic weight to length ratio were apparently decreased, while the colon length was increased. The pathological damage and colitis severity were lighter in the inhibitor group than that in the DSS group. Inhibiting ATX reduced the expression of ATX, LPA receptor, and CD34 and also decreased the percentages of Th17 cells in spleens and MLNs and the expressions of IL-17A and IL-21, as well as the factors in Th17 cell signaling pathway including IL-6, ROR-γt, and STAT3 in colonic tissue. ATX-LPA axis blockade could alleviate inflammation by suppressing Th17 cell differentiation in chronic UC.

Alpha-glucosidase inhibitor 1-Deoxynojirimycin promotes beige remodeling of 3T3-L1 preadipocytes via activating AMPK.

Obesity is a serious health challenge in the world, and searching effective drugs to cure obesity is of great importance. 1-Deoxynojirimycin (DNJ) is extracted from mulberry leaves and acts as an α-glucosidase inhibitor to lower blood glucose. Recent studies demonstrated that it also has anti-obesity effect, but the mechanisms remain unknown. In our present study, we mainly examined the effects of DNJ on beige remodeling of 3T3-L1 preadipocytes. We observed that DNJ didn't affect the mRNA levels of fatty acid binding protein 4 (aP2), peroxisome proliferator-activated receptor γ (PPARγ), preadipocyte factor-1 (Pref-1) as well as the mitochondrial uncoupling protein 1 (UCP1), PR domain containing protein 16 (PRDM16), transmembrane protein 26 (TMEM26) in undifferentiated preadipocytes. But after inducing 3T3-L1 preadipocytes to differentiation with white or beige adipogenic medium, DNJ significantly reduced aP2, PPARγ and Pref-1 expressions, while up-regulated the expressions of UCP1, PRDM16 and TMEM26, accompanying with decreased lipid deposition. The ratio of p-AMPK/AMPK was up-regulated by DNJ (10 µM) treatment for 10 days, and the effects of DNJ on p-AMPK/AMPK, UCP1 and PRDM16 could be blocked by AMPK inhibitor Compound C. These results demonstrated that hypoglycemic agent DNJ could suppress the adipogenesis during the differentiation of white preadipocytes, and promote the switch of white preadipocytes to beige adipocytes via activating AMPK, which provided new mechanisms for explaining the benefits of DNJ on obesity-related disorders.

Effect of compound sophorae decoction on dextran sodium sulfate (DSS)-induced colitis in mice by regulating Th17/Treg cell balance.

OBJECTIVE: Compound sophorae decoction, a Chinese medicinal formulae composed of six Chinese herbs, is effective for the clinical treatment of ulcerative colitis (UC). Some of its effective monomers had been proven to have suppressive effect on UC models. The aim of this study is to further explore the mechanism whether compound sophorae decoction ameliorates dextran sodium sulfate (DSS)-induced mice colitis by regulating the balance between T helper (Th) 17 and regulatory T (Treg) cells. METHODS: Experimental model of UC, established by drinking water with DSS, was treated with compound sophorae decoction and mesalazine. The stool, activity, body weight of the mice, colon length and colon histopathology were observed to evaluate severity of colitis. The concentration of cytokines in colonic tissues were detected by ELISA. The expression of phosphorylated nuclear factor-kappaB (NF-κB) p65, STAT3 and phosphorylated STAT3 in colonic tissues were determined by western blotting and immunohistochemistry. The percentage of Th17 and Treg cells in spleen and mesenteric lymph nodes (MLNs) were detected by flow cytometry. The levels of transcription factor ROR-γt and FOXP3 in colon tissues were detected by qRT-PCR and immunohistochemistry. RESULTS: The aqueous extract of compound sophorae decoction was able to improve the symptoms and pathological damage of mice. The body weight of mice were increased and DAI were significantly decreased; ulcers were slighter than DSS group. The administration of compound sophorae decoction reduced the level of inflammatory factors interleukin (IL)-1ß, tumor necrosis factor (TNF)-α and phospho-NF-κB p65, and also decreased the proportions of Th17 cells in spleen and MLNs and the expression of ROR-γt, IL-17A, STAT3, IL-6 in colonic tissues; while the percentage of Treg cells in spleen and MLNs and the expression of FOXP3, transforming growth factor (TGF)-ß1, IL-10 in colonic tissues were upregulated. CONCLUSION: Overall, this study suggested that compound sophorae decoction significantly improves the symptoms and the pathological damage of mice with colitis and influences the immune function by regulating Th17/Treg cell balance in DSS-induced colitis in mice.

Extracellular Vesicles Derived from Bone Marrow Mesenchymal Stem Cells Protect against Experimental Colitis via Attenuating Colon Inflammation, Oxidative Stress and Apoptosis.

The administration of bone mesenchymal stem cells (BMSCs) could reverse experimental colitis, and the predominant mechanism in tissue repair seems to be related to their paracrine activity. BMSCs derived extracellular vesicles (BMSC-EVs), including mcirovesicles and exosomes, containing diverse proteins, mRNAs and micro-RNAs, mediating various biological functions, might be a main paracrine mechanism for stem cell to injured cell communication. We aimed to investigate the potential alleviating effects of BMSC-EVs in 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis model. Intravenous injection of BMSC-EVs attenuated the severity of colitis as evidenced by decrease of disease activity index (DAI) and histological colonic damage. In inflammation response, the BMSC-EVs treatment significantly reduced both the mRNA and protein levels of nuclear factor kappaBp65 (NF-κBp65), tumor necrosis factor-alpha (TNF-α), induciblenitric oxidesynthase (iNOS) and cyclooxygenase-2 (COX-2) in injured colon. Additionally, the BMSC-EVs injection resulted in a markedly decrease in interleukin-1ß (IL-1ß) and an increase in interleukin-10 (IL-10) expression. Therapeutic effect of BMSC-EVs associated with suppression of oxidative perturbations was manifested by a decrease in the activity of myeloperoxidase (MPO) and Malondialdehyde (MDA), as well as an increase in superoxide dismutase (SOD) and glutathione (GSH). BMSC-EVs also suppressed the apoptosis via reducing the cleavage of caspase-3, caspase-8 and caspase-9 in colitis rats. Data obtained indicated that the beneficial effects of BMSC-EVs were due to the down regulation of pro-inflammatory cytokines levels, inhibition of NF-κBp65 signal transduction pathways, modulation of anti-oxidant/ oxidant balance, and moderation of the occurrence of apoptosis.