目的:本研究的目的是探讨MAFbZIP转录因子B(MAFB)是否可以减轻葡聚糖硫酸钠(DSS)诱导的小鼠和LPS诱导的IEC-6细胞的溃疡性结肠炎(UC)。
方法:利用DSS和LPS建立UC体内外模型,分别。每天记录小鼠体重和疾病活动指数(DAI)评分,测量结肠长度。此外,利用异硫氰酸荧光素葡聚糖(FITC-葡聚糖)探针评价渗透性。利用H&E染色评估DSS诱导的结肠炎小鼠的组织病理学变化。接下来,qRT-PCR检测IL-1β,IL-6,TNF-α,体内和体外IL-10水平。此外,MDA的水平,SOD,CAT,在结肠组织中评估GSH。此外,免疫印迹法检测结肠炎小鼠和IEC-6细胞中紧密连接蛋白和NF-κB通路相关蛋白的表达,免疫组织化学和免疫荧光。
结果:在DSS诱导的结肠炎小鼠中,MAFB水平下调。此外,MAFB的上调通过抑制DSS诱导的炎症保护小鼠免受DSS诱导的结肠炎,氧化应激,肠屏障受损。我们还证明了在DSS引起的结肠炎小鼠中,MAFB的上调使NF-κB途径失活。随后,我们观察到MAFB上调可抑制LPS引起的IEC-6细胞上皮屏障损伤和炎症反应。此外,MAFB过表达可抑制IEC-6细胞NF-κB通路的激活。
结论:MAFB的上调可能通过抑制NF-κB通路抑制炎症和肠屏障损伤来保护UC。
OBJECTIVE: The aim of this study was to explore whether MAF bZIP transcription factor B (
MAFB) might alleviate ulcerative colitis (UC) in dextran sulfate sodium (DSS)-induced mice and LPS-induced IEC-6 cells.
METHODS: UC in vivo and in vitro model was established by using DSS and LPS, respectively. The mice body weight and disease activity index (DAI) score were recorded daily, and colon length was measured. Moreover, the permeability was evaluated utilizing a fluorescein isothiocyanate dextran (FITC-Dextran) probe. Histopathological changes of DSS-induced colitis mice was assessed utilizing H&E staining. Next, qRT-PCR was performed to detect IL-1β, IL-6, TNF-α, and IL-10 level in in vivo and in vitro. Furthermore, the level of MDA, SOD, CAT, and GSH were evaluated in colon tissues. Besides, the expressions of tight junction proteins and NF-κB pathway relative proteins were examined in colitis mice and IEC-6 cells using western blot, immunohistochemistry and immunofluorescence.
RESULTS: MAFB level was downregulated in DSS-induced colitis mice. Moreover, the upregulation of
MAFB protected mice from DSS-induced colitis by suppressing DSS-induced inflammation, oxidative stress, and intestinal barrier impairment. We also demonstrated that the upregulation of
MAFB inactivated NF-κB pathway in DSS-caused colitis mice. Subsequently, we observed that MAFB upregulation could inhibit LPS-caused epithelial barrier impairment and inflammation in IEC-6 cells. Additionally,
MAFB overexpression could suppress the activation of NF-κB pathway in IEC-6 cells.
CONCLUSIONS: The upregulation of MAFB could protect against UC via the suppression of inflammation and the intestinal barrier impairment through inhibiting the NF-κB pathway.