黄芩多糖提取条件优化方法及其对溃疡性结肠炎小鼠的疗效研究

Optimization of Extraction Condition for Polysaccharides from Scutellaria Baicalensis Georgi and Study of Its Effect on Mice with Ulcerative Colitis

目的:基于响应面法探讨黄芩多糖提取工艺的优化方法,并评价优化条件下所得黄芩多糖对溃疡性结肠炎(UC)模型小鼠的疗效。方法:以多糖得率为指标,在单因素试验的基础上,对实验数据进行二项式回归拟合,得到提取多糖的最优工艺参数。取60只C57BL/6小鼠适应性喂养1周,随机分为空白组、模型组、阳性药组(美沙拉嗪,100 mg/kg)及黄芩多糖低、中、高剂量组(50,100,200 mg/kg) 6组,每组10只。除空白组外,其余各组均连续7 d自由饮用3%葡聚糖硫酸钠(DSS)水溶液建立急性期UC小鼠模型。造模开始即按分组灌胃给药,空白组及模型组给予等量生理盐水,每天1次,连续10 d。计算小鼠疾病活动指数(DAI),观察结肠组织病理学改变,进行组织学损伤评分,测定结肠组织中髓过氧化物酶(MPO)活性,检测小鼠血清及结肠组织中白细胞介素(IL)-1β、IL-18、肿瘤坏死因子-α(TNF-α)的水平。结果:提取多糖的最优工艺参数为提取时间4.3 h、提取温度93℃、液料比24∶1,在此条件下多糖得率预测值为6.58%,验证值6.45%,两者偏差为2.02%,该模型预测性良好。动物实验表明,黄芩多糖可回调溃疡性结肠炎小鼠DAI,修复病理组织损伤、降低组织学损伤评分,降低MPO活性,并降低血清及结肠组织中IL-1β、IL-18、TNF-α水平。结论:响应面法得到的黄芩多糖提取工艺参数准确、可靠,所提取的黄芩多糖对UC小鼠具有较好的治疗作用。

Objective:To optimize the extraction condition for polysaccharides from Scutellaria baicalensis Georgi(PSB) using response surface methodology(RSM) and to study its effect on ulcerative colitis(UC) in mice. Methods:Taking the yield of PSB as the index,on the basis of single factor experiment,binomial regression was fit using experimental data to obtain the optimized parameters for the extraction of polysaccharides. After adaptive feeding for one week 60 C57 BL/6 mice were randomly divided into blank group,model group,positive drug group(mesalazine,100 mg/kg) and PSB low,medium and high dose groups(50,100,200 mg/kg),totally 6 groups,10 mice in each group. Except for the blank group,the mice in other groups drank 3% dextran sodium sulfate(DSS) aqueous solution freely for 7 days to establish an acute UC mouse model. At the beginning of modeling,the mice were given intragastric administration in each group. The blank group and model group were given the same amount of normal saline once a day for 10 consecutive days. The disease activity index(DAI) of mice was scored,the pathological changes of colon tissue were observed,histological damage score,myeloperoxidase(MPO) activity was measured,and levels of interleukin(IL)-1β,IL-18,tumor necrosis factor(TNF)-α in mouse serum and colon tissue were de tected. Results:On the optimal condition for extracting PSB,extraction time was 4.3 h,temperature was at 93 ℃,and the ratio of V/W was 24∶1. Under this condition,the predicted and experimentally measured yield of PSB were 6.58% and 6.45%,respectively,with a relative error between them at 2.02%,indicating a good predictive ability of this model. Animal experiments showed that PSB could regulate DAI of mice with UC,alleviate pathological tissue injury,reduce histological damage score,reduce the MPO activity,and reduce the expression levels of pro-inflammatory cytokines of IL-1β,IL-18 and TNF-α both in serum and colon tissues. Conclusion:The extraction process parameters for PSB obtained by RSM are accurate and reliable,and the obtained PSB has a good therapeutic effect on mice with UC.