五甲基槲皮素及胃袖状切除术对乳鼠腹腔注射链脲佐菌素诱导2型糖尿病大鼠模型的效应研究

发布时间：2018-04-05 21:22

本文选题：五甲基槲皮素　切入点：STZ　出处：《华中科技大学》2011年博士论文

【摘要】：T2DM是最常见的内分泌代谢紊乱性疾病之一,近年来其发病率在全世界范围内迅速攀升。T2DM在临床上主要以外周组织对胰岛素的敏感性进行性下调且胰腺β细胞凋亡坏死及其功能持续性衰退为主要病理生理表现。基于T2DM的流行病学特点,近年来有关T2DM的病因学、病理生理学及其治疗学的研究在全世界范围内开展得如火如荼。五甲基槲皮素是天然多甲氧基黄酮家族(PMF)的成员之一,也是槲皮素的甲基化衍生物之一,主要存在于沙棘果中。大量研究结果表明,PMF家族成员具有多种药理活性,如抗糖尿病、抗炎等；相应的,也有文献报道PMQ具有抗肿瘤、抗心肌肥厚等作用,然而迄今为止,有关PMQ调节机体糖脂代谢稳态的研究还未见诸报道。胃袖状切除术原是外科减肥手术的一部分,由于其具有手术时间短、难度低、术后并发症少等特点而广受外科医生和病患的青睐。有研究结果表明,胃袖状切除术在减肥的同时还可显著降低肥胖患者显著升高的血糖水平,改善胰岛素抵抗,调节脂代谢紊乱等。鉴于以上研究基础,我们设想：PMQ及胃袖状切除术在乳鼠腹腔注射STZ诱导T2DM大鼠模型中是否也具有改善糖脂代谢紊乱的作用呢?据此,本研究主要分为三个部分。第一部分乳鼠腹腔注射STZ诱导2型糖尿病大鼠模型的建立目的：建立乳鼠腹腔注射STZ诱导T2DM大鼠模型并掌握其基本特点,为后期研究打下基础。方法：于华中科技大学同济医学院动物饲养中心购回健康SD大鼠(160-180 g,雌性大鼠数量：雄性大鼠数量=2：1)正常饲养,至雌性大鼠体重达280 g且雄性大鼠体重达350 g左右时按照1雄2雌比例进行配种,期间正常饲养,保持饲养间温度22±2℃,湿度50±5%及12h光照周期,并密切跟踪观察雌性大鼠的体重及体型。于雌性大鼠产前3天将其提出分笼,单独饲养。雄性乳鼠出生后48±2h内腹腔注射STZ(90mg/kg)。待乳鼠28日龄时断乳分笼,正常饲养,于其6、8、10、12、14及16周龄时检测其空腹及餐后血糖、甘油三酯、胆固醇、胰岛素及体重水平,以掌握该模型的基本特征。结果：按此方法造模,模型鼠成年后状态较好,但体重显著性降低,空腹血糖水平进行性升高,餐后血糖及餐后甘油三酯水平显著高于正常大鼠,空腹甘油三酯水平、空腹和餐后胆固醇水平升高不明显,空腹胰岛素水平显著性降低。结论：乳鼠腹腔注射STZ诱导T2DM大鼠模型较好的模拟了人类T2DM的病理生理特征及其典型病程,即疾病早期主要表现为显著升高的餐后血糖水平及糖耐量受损,后期空腹血糖水平升高且伴有明显的脂代谢紊乱。该模型的成模率为100%,是一种较理想的T2DM动物模型,可为抗糖尿病新药的初期筛选提供理想平台。第二部分PMQ对乳鼠腹腔注射STZ诱导2型糖尿病大鼠模型的药效学研究目的：于乳鼠腹腔注射STZ诱导2型糖尿病大鼠模型中筛选PMQ是否具有改善糖脂代谢紊乱的作用。方法：实验分为六组(n=9-12)：正常对照组；糖尿病组(模型对照组)；PMQ各剂量组(模型鼠分别灌胃给予PMQ 2.5,5,10,20mg/kg)。各组大鼠自6周龄开始给药,给药时间定为每日8：30 a.m.,持续10周。正常对照组和糖尿病组大鼠给予药物溶剂灌胃给药。本研究中所选PMQ剂量是基于本实验室前期PMQ于大鼠体内药代动力学特征的实验结果。给药期间每日称取大鼠体重,并跟踪记录其饮水和进食量。分别在大鼠12和16周龄(给药后6和10周)时检测各组大鼠空腹及餐后血糖、甘油三酯和胰岛素水平。给药结束后进行OGTT实验,宰杀大鼠取肝、胰腺、肾脏等器官,计算器官指数,并做胰腺组织切片行HE染色。结果：PMQ给药可剂量依赖性地降低模型大鼠显著升高的餐后血糖和甘油三酯水平,延缓其空腹血糖水平的升高,改善糖尿病大鼠的多饮多食症状及其糖耐量受损程度,显著上调外周组织的胰岛素敏感性,降低糖尿病大鼠异常升高的血清谷丙转氨酶水平。结论：PMQ在乳鼠腹腔注射STZ诱导T2DM大鼠模型中表现出显著的改善糖脂代谢紊乱的作用。第三部分胃袖状切除术对乳鼠腹腔注射STZ诱导2型糖尿病大鼠模型的效应研究目的：研究胃袖状切除术于乳鼠腹腔注射STZ诱导T2DM大鼠模型中对模型大鼠体重及其糖代谢的影响。方法：实验分为手术组(n=6)和假手术组(n=6)。模型大鼠术前禁食12h,可自由摄水。大鼠腹腔注射苯巴比妥钠(40 mg/kg),待动物麻醉好后将其仰面固定于动物手术台上,术前30min预防性肌注青霉素G(50 mg/kg)以防止术后感染。备皮,沿腹中线做一长约3-4厘米的切口,分离皮肤及肌肉层,小心将胃游离出来,用无创性止血钳沿胃大弯将胃固定,用无菌外科手术刀片沿着胃大弯切除约70%-80%体积的胃组织,残胃用碘伏擦拭消毒后用5-0规格手术线缝合,缝合结束后松开无创止血钳,检查缝合效果,如有出血点适当补针。手术完毕后用无菌生理盐水冲洗腹腔,最后用3-0规格手术线缝合腹腔。假手术组与手术组步骤基本相同,但并不切除胃组织。各组大鼠术后恢复一周,至第2周开始每周记录其体重、进食和饮水量,术后第4周和第8周两个时间点分别检测大鼠空腹和餐后血糖水平,实验结束时检测各组大鼠空腹胰岛素、GIP、活性GLP-1及ghrelin水平。结果：与假手术组相比,胃袖状切除术可显著控制模型大鼠术后的体重增长,减少其饮水和进食量,但胃袖状切除术在乳鼠腹腔注射STZ诱导T2DM大鼠模型中没有明显的改善糖代谢紊乱的作用,相应的,两组大鼠糖代谢相关激素如GLP-1、GIP和胰岛素水平没有统计学差异。与假手术组大鼠相比,SG术后手术组大鼠的ghrelin水平显著降低。结论：胃袖状切除术可显著控制大鼠体重,但不能改善乳鼠腹腔注射STZ诱导T2DM大鼠的糖代谢紊乱。
[Abstract]:T2DM is one of the most common endocrine and metabolic disorders in the world . In recent years , the incidence of T2DM has been increasing rapidly worldwide . In recent years , the sensitivity of T2DM to insulin has been downregulated and the necrosis of pancreatic 尾 - cell apoptosis and its function continue to decline . Based on the epidemiological characteristics of T2DM , the study of etiology , physiopathology and therapeutics of T2DM in recent years has been in full swing around the world .

The pentamethylquercetin is one of the members of the natural polymethoxyflavone family ( PMF ) , also one of the methylated derivatives of quercetin , which is mainly found in the fruit of sea buckthorn . The results show that the PMF family members have various pharmacological activities , such as anti - diabetes , anti - inflammation , etc .
It is also reported that PMQ has anti - tumor and anti - myocardial hypertrophy . So far , the study of PMQ regulating the steady state of glycolipid metabolism has not been reported .

The gastrectomy is a part of the surgical weight - losing operation , because it has the characteristics of short operation time , low difficulty , less postoperative complications and so on . The results show that the gastrectomy can significantly reduce the blood sugar level , improve insulin resistance , regulate lipid metabolism disorder , etc . , while losing weight .

In view of the above research foundation , it is envisaged that PMQ and gastrectomy can improve the metabolism of glycolipids in the model of rats with T2DM induced by intraperitoneal injection in rats .

Establishment of Model 2 Diabetic Rat Model Induced by Intraperitoneal Injection of Diabetic Mice

Objective : To establish a model of rats with T2DM induced by intraperitoneal injection of diabetic rats and to grasp the basic characteristics of rats . The results showed that the rats with T2DM induced T2DM were fed with intraperitoneal injection ( 90 mg / kg ) at the age of 6 , 8 , 10 , 12 , 14 and 16 .

Effect of the second PMQ on the model of 2 - type diabetic rats induced by intraperitoneal injection in rats

Objective : To investigate whether PMQ has the effect of improving the metabolism of glycolipids in rats with type 2 diabetes induced by intraperitoneal injection in rats . Methods : The experiment was divided into six groups ( n = 9 - 12 ) : normal control group ;
Diabetic group ( model control group ) ;
PMQ 2.5 , 5 , 10 , 20 mg / kg was administered in each dose group of PMQ ( model mice respectively ) . Plasma glucose , triglyceride and insulin levels were measured in rats at 12 and 16 weeks of age ( 6 and 10 weeks after administration ) .

Effect of third partial gastrectomy on model of 2 - type diabetic rats induced by intraperitoneal injection in rats

Objective : To study the effects of gastric sleeve resection on body weight and glucose metabolism in rats with T2DM induced by intraperitoneal injection in rats . Methods : The rats were divided into two groups : operation group ( n = 6 ) and sham operation group ( n = 6 ) .

【学位授予单位】：华中科技大学
【学位级别】：博士
【学位授予年份】：2011
【分类号】：R285.5;R-332

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