ABSTRACT
AIM:To observe the effect of interleukin-27 (IL-27) on the pathological changes and the expres-sion and activation of NOD-like receptor protein 3 (NLRP3) inflammasome in the colonic tissues of the mice with dextran sodium sulfate (DSS)-induced experimental colitis. METHODS:Male C57BL/6 mice (n=48) were randomly divided into control group (given unrestricted diet), DSS group (drinking 3% DSS solution), IL-27 (500 ng) group and IL-27 (1 μg) group (intraperitoneal injection of 500 ng and 1 μg IL-27 on the basis of drinking DSS solution, respectively). After treatment for 12 d, intestinal inflammation in the mice was evaluated, the pathological changes of the colonic tissues were observed by HE staining, and the disease activity index ( DAI) score and histological index ( HI) score were calculated. The colonic tissues were collected for immunohistochemistry, qPCR and Western blot detections. The serum was prepared for ELISA. RESULTS:Compared with control group, the DAI score and HI score in model group indicated that the colo-nic inflammation was more obvious (P<0.05), the mRNA expression of NLRP3 and IL-1β was increased, the protein levels of NLRP3 and cleaved caspase-1 were elevated, and the releases of IL-1β and IL-18 in the serum were also increased (P<0.05). Compared with DSS group, the DAI score and HI score in IL-27 (1 μg) group indicated that the colonic in-flammation was obviously attenuated, the mRNA expression of NLRP3 and IL-1β was decreased, the protein levels of NLRP3 and cleaved caspase-1 were suppressed, and the releases of IL-1β 和 IL-18 in the serum were also decreased (P<0.05). No difference of the above indexes between DSS group and IL-27 (500 ng) group was observed except the de-creases in the releases of IL-1β and IL-18 in the serum in IL-27 (500 ng) group. CONCLUSION:IL-27 alleviates the inflammation in DSS-induced colitis mice and inhibits the expression and activation of NLRP3 inflammasome.
ABSTRACT
AIM:To detect the expression of CBir1 in the serum and colon tissue and mast cell degranulation in the tissue of 2,4,6-trinito-benzene-sulfonic acid ( TNBS)-induced colitis in mice with different interventions. ME-THODS:SPF male BALB/c mice were randomized into 6 groups (12 mice in each group):normal control group, normal saline group, 50% alcohol group, 50% alcohol+TNBS group, 50% alcohol+TNBS+lipopolysaccharide (LPS) +ovalbu-min (OVA) group and 50% alcohol+TNBS+ketotifen group. Corresponding treatment was given to each group, and the disease activity index (DAI) of the mice was evaluated. The mice were sacrificed on day 22 after treatment. The colon tis-sues were evaluated by histological index (HI) scoring. Serum concentrations of anti-CBir1, mast cell tryptase (MCT) and histamine were measured by ELISA. The expression of CBir1, toll-like receptor 5 (TLR5) and MCT in the colon tissues was detected by immunohistochemistry. RESULTS:Compared with the normal control group, the DAI score, HI score and CBir1, anti-CBir1, MCT, TLR5, histamine concentrations in colon tissues and serum were all significantly higher in 50% alcohol+TNBS group, 50% alcohol+TNBS+ketotifen group and 50% alcohol+TNBS+LPS+OVA group (P<0.05). The DAI score, HI score and anti-CBir1, CBir1, MCT, histamine levels in 50% alcohol+TNBS group were lower than those in 50% alcohol+TNBS+LPS+OVA group (P<0.05). The DAI score, HI score and anti-CBir1, TLR5, hista-mine, CBir1 Levels in 50% alcohol+TNBS group were higher than those in 50% alcohol+TNBS+ketotifen group ( P<0.05). Normal saline group and 50% alcohol group had no statistically significant difference in comparison with normal control group. In TNBS model group, serum concentration of anti-CBir1 was positively correlated with MCT concentration (r=0.648, P<0.01) and histamine concentration (r=0.751, P<0.01). CONCLUSION:The heavier degree of in-flammation in TNBS-induced colitis, the higher levels of the CBir1 and the degranulation of mast cells. There is a positive correlation between the expression of CBir1 and the degranulation of mast cells in TNBS-induced colitic mice.
ABSTRACT
AIM:To investigate the protective effect of mucin 2(MUC2)on intestinal mucosa of colitis model mice,and to explore the correlation between the expression of anti-CBir1 flagellin antibody and MUC2.METHODS:The mice were randomly divided into normal control group,2,4,6-trinitrobenzenesulfonic acid(TNBS)group,lipopolysaccha-ride(LPS)+ovalalbumin(OVA)+TNBS group and ketotifen+TNBS group.The expression of MUC2 in colon tissue was determined by PAS staining and immunohistochemistry, and the anti-CBir1 antibody level in the serum of mice in each group was measured by ELISA.RESULTS:The scores of disease activity index and histological index in TNBS group were higher than those in normal control group(P<0.05).The scores in LPS +OVA+TNBS group were much higher than those in TNBS group(P<0.05).However, the values in ketotifen +TNBS group were lower than those in TNBS group (P<0.05).PAS staining showed a decrease in goblet cells in TNBS group.Compared with TNBS group,the colonic mu-cosa integrity in LPS+OVA+TNBS group was destroyed, and the number of goblet cells in ketotifen +TNBS group in-creased significantly.Immunohistochemical staining showed that the expression of MUC 2 in the intestinal tract of each mo-del group was basically consistent with the results of PAS staining.The serum anti-CBir1 antibody level in TNBS group was higher than that in normal control group(P<0.05), and that in LPS+OVA+TNBS group was significantly higher than that in TNBS group(P<0.05),whereas that in ketotifen +TNBS group was decreased slightly(P<0.05).CONCLU-SION:MUC2 plays a protective role in the pathogenesis of colitis in mice,and there is a negative correlation between the expression of MUC2 and the bacterial flagellin in the intestinal mucosa of mice with colitis.