芒果苷对DSS诱导的小鼠溃疡性结肠炎的预防作用及其抗炎机制初步研究

Preventive Effect of Mangiferin on DSS Induced Ulcerative Colitis in Mice and Preliminary Study of the Mechanisms on Anti-inflammation

本文研究芒果苷(MGF)对小鼠溃疡性结肠炎(UC)的预防作用及其作用机制。选用昆明种小鼠,用葡聚糖硫酸钠(DSS)复制UC模型。动物随机分成空白对照组、DSS模型对照组、柳氮磺胺吡啶(SASP)阳性对照组(900 mg/kg)、MGF组(300、150、75 mg/kg)、MGF固体分散体(MGF-SD)组(折合成MGF为300 mg/kg)。除空白对照组外,其他组小鼠自由饮用2.5%DSS水溶液造模,连续14 d,造模的同时灌胃给予相应药物干预。隔天进行疾病活动指数(DAI)评分。于第14 d处死小鼠,对结肠进行大体形态损伤指数(CMDI)评分,HE染色后进行结肠病理组织学指数(CHPI)评分,ELISA法检测结肠组织IL-1β、IL-4、IL-6和IL-10水平。结果显示,模型对照组小鼠DAI、CMDI和CHPI评分均显著增加(P<0.05),结肠组织中IL-1β、IL-6水平显著升高(P<0.05),IL-4、IL-10水平显著降低(P<0.01)。MGF可显著改善UC小鼠的DAI、CMDI和CHPI评分。MGF组和MGFSD组均能显著降低结肠组织IL-1β水平(P<0.05);MGF高剂量组和MGF-SD组显著降低结肠组织IL-6水平,但组间无显著差异(P>0.05);各药物组对结肠组织IL-4和IL-10水平的影响与模型组比较均无显著性(P>0.05)。表明MGF对DSS诱导的小鼠UC具有较好的预防作用,可能与下调结肠组织中IL-1β、IL-6水平有关,进而调节结肠组织中促炎因子与抗炎因子的平衡。提高MGF的溶解度不能提高其对UC的防治作用。

In this study,the preventive effect of mangiferin （MGF） on dextran sulfate sodium （DSS） induced ulcerative colitis （UC） in mice and its influence on inflammatory cytokines were investigated. KM mice were randomly divided into blank control group, model control group, SASP positive control group （900 mg/kg）, M GF groups （ 300,150,75 mg/kg ） and MGF-SD group （equivalent to 300 mg/kg of MGF）. Ulcerative colitis in mice model induced by DSS was prepared within 14 days. After intervened with medical drug daily on time, disease activity index （DAI）, colon gross morphological damage index （CMDI） and colon histopathology index （CMDI） should be recorded as a judgment to evaluate the effect. The contents of IL-1β, IL-4,IL-6 and IL-10 were detected by ELISA. As shown in the result, there were significandy increased for CHPI,DAI,CMDI scores and the IL-1β,IL-6 levels （P 〈0.05） in modal group,but obviously decreased for IL-4, IL-10 levels. Compared to model group, CHPI, DAI and CMDI of MGF were significantly decreased （P〈0.05） ,the level of IL-1β in MGF and MGF-SD groups were significantly decreased （ P 〈 0.05 ）, the level of IL-6 in MGF high dose group and MGF-SD group were signitl- candy down regulated （P 〈 0.05）, but there was no signifi- cant difference between the two groups （ P 〉 0. 05 ）, the same to the levels of IL-4 and IL-10 in all drug intervention groups. It was indicated that MGF showed obvious preventive effect against DSS induced ulcerative colitis in mice. It may be related to the down-regulation of IL-1 and IL-6 in colon tlssues,and further to regulate the balance of pro-inflammatory eytokines and anti-inflammatory factors. Increasing the solubillty of MGF could not result in the enhancement of this preventive effect.