运动结合单不饱和脂肪酸摄入对大鼠胰岛素抵抗的影响

目的:通过观察运动结合单不饱和脂肪酸对SD大鼠胰岛素抵抗的影响,为糖尿病患者科学合理饮食及运动提供理论依据。方法:将SD大鼠随机分为空白对照组(C组)、饱和脂肪酸组(S组)、单不饱和脂肪酸膳食组(M组)、单不饱和脂肪酸+运动组(ME组),分别观察体重、体脂、血糖、空腹胰岛素(FINS)、总胆固醇(TC)、甘油三酯(TG)、内脏脂肪素(visfatin)的变化。结果:与C组相比,S组体重、体脂均增加(P0.01),血糖、FINS、TG、TC升高(P0.01),visfatin降低(P0.05);与S组相比,M组体重及体脂无明显变化,但ME组体重及体脂相比S组及M组均有降低(P0.05),M组及ME组血糖、FINS下降,TG、TC降低(P0.01),LDL-C的水平下降(P0.01),visfatin的水平升高(P0.01),并且ME组血糖、FINS、TG、TC、LDL-C的水平低于M组(P0.05),而血浆visfatin的水平则明显高于M组(P0.05)。结论:与饱和脂肪酸饮食相比,运动及单不饱和脂肪酸饮食共同干预可以明显改善大鼠的胰岛素抵抗,并且变化的机制可能与内脏脂肪素的降低有关。     

普洱茶提取物对单纯性肥胖大鼠MC4R基因表达的影响

为观察普洱茶提取物对高脂饮食诱导肥胖大鼠脂肪组织中黑皮素受体-4(MC4R)基因表达的影响,进一步探讨普洱茶抗肥胖的相关机制,本试验将大鼠随机分为正常对照组、高脂饲料组、高脂饲料+普洱茶提取物干预组,构建单纯性肥胖模型。每周测量大鼠体重,3个月试验结束后测量大鼠终末体重、脂肪组织重量,检测甘油三酯(TG)、总胆固醇(TC)、低密度脂蛋白(LDL-C)等血脂水平。提取大鼠附睾脂肪组织,采用实时荧光定量逆转录聚合酶链反应(RT-PCR)和免疫印迹试验(Western blot)检测肥胖相关基因MC4R mRNA和蛋白的表达水平。结果显示:普洱茶能显著减轻高脂饮食大鼠体重和脂肪组织重量,降低体脂比,并降低各项血脂水平;普洱茶提取物能显著上调MC4R基因和蛋白的表达。这表明普洱茶提取物具有减肥降脂作用,其分子机制可能与上调肥胖重要调节因子MC4R有关。     

下丘脑Orexin 对肥胖大鼠能量代谢的影响

目的:探讨下丘脑注射OXR-1选择性受体拮抗剂ACT-335827对肥胖大鼠代谢的效果。方法:通过高脂饮食建立肥胖大鼠模型,采用CODA 8通道高通量非侵入性血压系统(EMKA)测量血压;所有脂类都使用商品酶试剂盒和TOSHIBA-40FR全自动分析仪测量;空腹血糖采用葡萄糖氧化酶法;空腹胰岛素采用放射免疫法测定。肥胖大鼠出现代谢紊乱后,给予ACT-335827处理,检测大鼠体重、血压、脂肪、甘油三酯、总胆固醇、高密度脂蛋白、低密度脂蛋白、游离脂肪酸(NEFA)、瘦素、空腹血糖及空腹胰岛素等的变化。结果:与普通饮食组相比,经过10周高脂饮食,高脂饮食组大鼠体重显著升高(P0.05),给予ACT-335827处理后,普通大鼠的体重、血压、脂肪含量、脂代谢等均无明显变化;与高脂饮食和高脂饮食加生理盐水处理组大鼠比较,高脂饮食加ACT-335827处理组肥胖大鼠的体重显著下降(P0.05),腹部和附睾脂肪含量下降(P0.05),低密度脂蛋白、甘油三酯、总胆固醇、瘦素水平下降(P0.05),空腹血糖及空腹胰岛素也显著降低(P0.05),但血压、肠系膜脂肪和肩胛棕色脂肪、高密度脂蛋白和NEFA无明显变化(P0.05)。结论:ACT-335827对肥胖大鼠的代谢紊乱具有改善作用,对肥胖大鼠有一定的减肥作用。     

葛根素对2型糖尿病大鼠的治疗作用*

目的:观察葛根素对2型糖尿病(T2DM)大鼠的治疗作用。方法:采用高糖高脂饲料喂养加一次性腹腔注射60 mg/kg链脲佐菌素的方法建立T2DM 大鼠模型,随机分为正常组,模型组,二甲双胍(40 mg/kg)组,葛根素低、中、高剂量(40,80,160 mg/kg)组,每组10只大鼠;造模成功后,灌胃给药4周,每周测量大鼠体重和空腹血糖(FBG),末次给药24 h后取血,收集血清,检测各组大鼠的血糖、血清甘油三酯(TG)、总胆固醇(TC) 、低密度脂蛋白-胆固醇(LDL-C)水平、高密度脂蛋白-胆固醇(HDL-C),血清天门冬氨酸氨基转移酶(AST)、丙氨酸氨基转移酶(ALT)活性,血清尿素氮(BUN)、肌酐(SCr)、尿酸(UA)水平。结果:干预4周后,与正常组比较,模型组大鼠体重显著降低(P＜0.01),FBG,TC,TG,LDL-C,ALT,AST,BUN,SCr,UA均显著升高(P＜0.01),而HDL-C 显著降低(P＜0.01);与模型组比较,二甲双胍组和葛根素各剂量组大鼠体重均显著增加(P＜0.01),FBG,TC,TG,LDL-C,ALT,AST,BUN,SCr,UA均显著降低(P＜0.01),而HDL-C显著升高(P＜0.01)。结论:葛根素能够减少T2DM大鼠体重降低幅度,降低血脂、血糖水平,可用于T2DM的治疗。     

罗格列酮对血脂异常大鼠氧化应激及炎症反应的影响

目的:探讨罗格列酮对血脂异常大鼠的氧化应激和炎症反应损伤的保护作用。方法:2月龄健康成年雄性大鼠30只,随机分成3组,每组10只,分别为对照组(普通饲料饲养)、高脂组(高脂饲料饲养)和罗格列酮组(高脂饲料饲养后5 mg·kg-1罗格列酮灌胃),其中血脂异常模型构建时间为5周,罗格列酮的干预时间为1周。第6周实验结束后对各组大鼠进行准确称重,采血,离心留取上清,全自动生化分析仪用于检测待测血清中甘油三脂(TG)、总胆固醇(TC)和低密度脂蛋白胆固醇(LDL-C)水平,酶联免疫吸附法(ELISA)用于检测过氧化物歧化酶(SOD)、丙二醛(MDA)、C-反应蛋白(CRP)、不对称二甲基精氨酸(ADMA)及一氧化氮(NO)产生量。在无菌条件下分别分离各组大鼠肾周、附睾和腹膜后的脂肪组织并准确称量,即为大鼠的内脏脂肪重量,并对上述10项指标进行两两相关性分析。结果:与对照组相比,高脂组的大鼠体重和内脏脂肪重量均显著增加(P0.05),血清TG、TC和LDL-C水平均显著增加(P0.05);NO产生量和血清SOD水平均显著减少(P0.05);血清MDA、CRP和ADMA水平均显著增加(P0.05)。与高脂组相比,罗格列酮组的大鼠体重和内脏脂肪重量均显著降低(P0.05),TG、TC和LDL-C水平略有改善,但差异并不显著(P0.05);NO产生量和血清SOD水平均显著增加(P0.05);血清MDA、CRP、ADMA水平均显著减少(P0.05),血清TG水平和SOD水平呈负相关(Y=-0.014X+2.967,P=0.001)。结论:罗格列酮对血脂异常的大鼠具有氧化应激和炎症反应损伤的保护作用。     

长短日照下绍鸭性成熟时间,下丘脑GnRH-I、POMC和NPY mRNA表达的差异

利用长日照和短日照环境调控绍鸭的性成熟时间,并采用反转录多聚酶链式反应(RT-PCR)方法, 检测两种日照组(n=6)鸭性成熟过程中下丘脑促性腺激素释放激素-Ⅰ(GnRH-Ⅰ)、阿片促黑激素皮质素 原(POMC)和神经肽Y(NPY)mRNA表达的发育性变化及日龄间差异。结果表明,长日照组性成熟时间较短 日照组提前30d。RT-PCR结果显示,两组鸭下丘脑GnRH-Ⅰ mRNA的发育性表达模式相似,从出雏至性成熟 过程中,其表达水平呈逐渐增加趋势;长日照组下丘脑GnRH-Ⅰ mRNA表达丰度均高于同日龄短日照组,并于 120日龄时其差异达显著水平。两组POMC mRNA的表达丰度呈现先增加后降低趋势,于性成熟前后显著下降; 日照长度对其基因表达具有显著影响。两组NPY mRNA表达水平分别于60和90日龄时显著升高,于性成熟时 显著下降,但光照对其基因表达无显著影响。下丘脑GnRH-Ⅰ基因表达的显著上调可能是禽类性成熟启动的关 键因素,也是长日照条件下绍鸭性早熟的主要原因;GnRH-Ⅰ表达的上调与下丘脑POMC和NPY mRNA表达变 化有关。     

脂肪因子Vaspin在运动与甲鱼油对老年肥胖大鼠胰岛素抵抗的作用*

目的: 从Vaspin在内脏脂肪组织mRNA表达、蛋白表达以及血浆浓度角度,探讨Vaspin在运动结合甲鱼油对老年肥胖大鼠胰岛素抵抗(IR)的调节作用。方法: 选取鼠龄3周的雄性SD大鼠(n=50),持续喂普通饲料至大鼠55周龄,根据体重无差异选取38只喂饲高脂饲料(脂肪含量占40%),建立老年肥胖模型,喂饲至大鼠周龄60周。建模成功后,随机选取24只分为4组(n=6),分别为肥胖模型组(OA)、运动组(OB)、单纯补充甲鱼油组(OF)、运动结合甲鱼油组(OBF)。(运动)干预方案:大鼠运动跑台坡度为0°、速度和时间(15 m/min,15 min)、组间休息5 min、4组/次,甲鱼油灌胃0.3～0.4 ml,1次/天,其他组灌胃相等剂量的生理盐水,5次/周,持续8周。8周后,取血测定大鼠血糖、血浆胰岛素和Vaspin浓度,取肾和睾丸周围内脏脂肪组织,检测脂肪组织Vaspin mRNA及蛋白的表达。结果: 与肥胖模型组相比,8周干预后,OB、OF和OBF组的血糖水平明显降低(P＜0.05,P＜0.01),OB和OBF组的血浆Vaspin浓度明显降低(P＜0.05,P＜0.01),血浆胰岛素浓度无明显变化,OB、OF和OBF组的IR、内脏脂肪组织中Vaspin mRNA和蛋白表达均明显降低(P＜0.01);与OBF组相比,OB和OF组的血糖、IR、血浆Vaspin浓度、内脏脂肪组织中Vaspin mRNA和蛋白表达各组间均无统计学意义(P＞0.05)。结论: 运动与甲鱼油均可以改善老年肥胖大鼠IR、降低血糖,伴随着内脏脂肪Vaspin mRNA表达、蛋白表达及其血浆浓度降低,但运动结合甲鱼油并不能取得更好的协同效果。     

运动对胰岛素抵抗大鼠肝脏BIM信号通路的影响*

目的: 探究运动干预对肥胖诱导的胰岛素抵抗大鼠肝脏BIM-JNK1-IRS1-Akt信号通路的影响。方法: 40只雄性SD大鼠随机分4组(n=10):对照组(普通膳食喂养16周);高脂膳食安静组(高脂膳食喂养16周);慢性运动组(高脂膳食喂养16周且后8周进行慢性运动干预,5%体重负重的游泳运动,1 h/d,5天/周)和急性运动组(高脂膳食喂养16周后进行同样5%体重负重的6 h急性运动干预,分两个3 h进行,中间间隔休息45 min)。干预结束后,所有大鼠称重后进行口服糖耐量和胰岛素释放实验,分别使用罗氏血糖仪和大鼠胰岛素ELISA试剂盒测定血糖含量和血清胰岛素含量,以胰岛素敏感性指数衡量胰岛素抵抗状态。Western blot方法检测肝脏Bcl-2细胞死亡调节因子(BIM),磷酸化c-Jun氨基末端激酶1(p-JNK1), 磷酸化胰岛素受体底物1(p-IRS1)和磷酸化蛋白激酶B(p-Akt)蛋白水平。结果: 与对照组大鼠相比,高脂膳食安静组大鼠体重和内脏脂肪质量显著增加(P＜0.01),胰岛素敏感性指数显著下降((P＜0.01);肝脏中BIM蛋白水平显著增加(P＜0.01),JNK1和IRS1磷酸化水平显著增加(P＜0.01),Akt磷酸化水平显著下降(P＜0.01)。与高脂膳食安静组相比,慢性运动组大鼠体重和内脏脂肪质量显著降低(P＜0.01),急性运动组大鼠体重和内脏脂肪质量无明显变化。与高脂膳食安静组相比,慢性运动组和急性运动组大鼠的胰岛素敏感性指数显著提高(P＜0.05),肝脏中BIM蛋白水平显著减少(P＜0.01),JNK1和IRS1磷酸化水平显著降低(P＜0.01),Akt磷酸化水平显著增加(P＜0.01)。结论: 慢性运动降低大鼠体重和内脏脂肪质量,急性运动并不影响大鼠体重和内脏脂肪质量,但两种运动方式都可以改善肥胖诱导的胰岛素抵抗,这可能与大鼠肝脏中BIM调节的JNK1-IRS1-Akt信号通路的改变有关。     

Dietary diacylglycerol suppresses high fat and high sucrose diet-induced body fat accumulation in C57BL/6J mice

Diacylglycerol (DG) comprises up to approximately 10% of various edible oils. In the present study, we examined the effects of dietary DG consisting mainly of 1,3-species on body weight, body fat accumulation, and mRNA levels of various genes involved in energy homeostasis in obesity-prone C57BL/6J mice. Five-month feeding with the high triacylglycerol (TG) diet (30% TG + 13% sucrose) resulted in significant increases in body weight, visceral fat accumulation, and circulating insulin and leptin levels compared with mice fed the control diet (5% TG). Compared with mice fed the high TG diet, body weight gain and visceral fat weight were reduced by 70% and 79%, respectively, in those fed the high DG diet (30% DG + 13% sucrose). In addition, circulating leptin and insulin levels were reduced to the respective control levels. Compared with high TG feeding, high DG feeding suppressed the elevation of leptin mRNA expression in adipose tissue, and up-regulated acyl-coenzyme (Co)A oxidase and acyl-CoA synthase mRNA expression in the liver. These results indicate that dietary DG is beneficial for suppression of high fat diet-induced body fat accumulation. Furthermore, it is suggested that structural differences in DG and TG, but not the composition of fatty acid, markedly affect nutritional behavior of lipids. -- Murase, T., T. Mizuno, T. Omachi, K. Onizawa, Y. Komine, H. Kondo, T. Hase, and I. Tokimitsu. Dietary diacylglycerol suppresses high fat and high sucrose diet-induced body fat accumulation in C57BL/6J mice. J. Lipid Res. 2001. 42: 372--378.     

No Specific Effect of Fluoxetine Treatment on Fasting Glucose,Insulin, Lipid Levels,and Blood Pressure in Healthy Men with Abdominal Obesity

In this paper we investigated the effect of fluoxetine (60 mg/d) on serum lipids, glucose and insulin concentrations and blood pressure by means of a randomized, double-blind placebo controlled trial. Thirty-eight overweight BMI: 26–30 kg/m²), nondiabetic, nonhypertensive men with an abdominal fat distribution (waist/hip ratio: >0.97) received dietary advice and placebo or fluoxetine for 12 weeks. The changes in serum parameters and blood pressure in the fluoxetine treated group were not different from the placebo treated group, despite a significantly larger weight loss in the fluoxetine group. In both groups serum total-cholesterol concentrations, serum LDL-cholesterol concentrations and tlie HDL/LDL ratio were significantly improved after treatment. Reductions in fasting glucose concentration and systolic blood pressure were only significant in the placebo group. A reduction of serum triglycerides and an increase of HDL-cholesterol were found in the fluoxetine treated group. In the total study population the changes in serum lipids seemed to be more strongly related to the change in total body fat or subcutaneous abdominal fat (assessed by MRI) compared to the change in visceral fat. The improvement of most of the serum lipids was related to tlie change in total body fat independent of the mechanism for attaining this fat loss. Our results indicate that fluoxetine treatment has no specific effect beyond that expected for weight loss on serum lipid, glucose and insulin concentrations, and blood pressure in overweight men.     

急、慢性运动对2型糖尿病大鼠脂肪PI3K/AKT/GLUT4通路的影响

目的:探讨急性和慢性运动对2型糖尿病(T2DM)大鼠脂肪组织明磷脂酰肌醇3激酶(PI3K)/蛋白激酶B(AKT)/葡萄糖运载体4(GLUT4)信号通路的影响。方法:15月龄SD雄性大鼠52只随机分为正常对照组(n=13)和高脂组(n=39),分别喂养普通和高脂饲料。8周后,高脂组体重＞正常对照组20％,注射小剂量STZ后,血糖＞16.7 mmol/l,造模成功。将糖尿病模型组随机分为糖尿病对照组(DC,n=13),糖尿病慢性运动组(DCE,n=13),糖尿病急性运动组(DAE,n=13)。DCE组进行8周的游泳运动,DAE组进行一次性游泳运动。测定血脂,血糖和血清胰岛素,Western blot法测定脂肪PI3K、AKT和GLUT4蛋白含量。结果:糖尿病组体重、血脂、血糖、胰岛素显著高于正常对照组(P均＜0.01);高密度脂蛋白胆固醇(HDL-C)水平降低(P＜0.05),脂肪组织中PI3K、AKT和GLUT4蛋白表达下降(P均＜0.01)。糖尿病慢性运动组体重、血脂、血糖、胰岛素均出现显著性下降(P均＜0.01);HDL-C升高(P＜0.05),脂肪PI3K、AKT和GLUT4蛋白表达上升(P＜0.01)。糖尿病急性运动组血脂、血糖、胰岛素下降(P均＜0.05);HDL-C升高(P＜0.05),脂肪PI3K、AKT和GLUT4含量显著上升(P均＜0.05)。结论:①高脂饮食结合小剂量STZ诱导的T2DM大鼠脂肪组织PI3K/AKT通路受损,降低了胰岛素的敏感性。②急性、慢性有氧运动,均可以通过PI3K/AKT通路,改善糖脂代谢紊乱,慢性运动略优于急性运动。     

Effects of diabetes on the dietary lipid alteration of R3230AC mammary carcinoma growth in rats

To examine the effects of diabetes on the alteration of R3230AC mammary tumor growth by dietary lipids, streptozotocin-induced diabetic rats were fed diets containing either 20% corn oil (HF), 20% hydrogenated cottonseed oil (HCTO), or 0% fat (FF). Diabetes resulted in lower tumor weights and body weights compared to those of intact animals. Unlike intact animals, relative tumor weight (g tumor/100 g body wt) of diabetic animals fed HF diets were not greater than those from animals fed FF diets. However, in these diabetic animals, growth of tumors in HF-fed rats was faster than in HCTO-fed rats, a relationship similar to that seen in intact rats. A surprising result was the almost twofold greater tumor weight/100 g body wt observed in diabetic FF-fed rats compared to those fed HCTO diets. Insulin binding to tumor plasma membranes from diabetic animals was higher in rats fed HF diets than in rats fed FF or HCTO diets. The tumor plasma membrane fatty acid composition of diabetic rats fed FF and HCTO diets displayed higher proportions of the monounsaturates (C18:1 and C21:1) and decreased amounts of the polyunsaturates (C18:2 and C20:4) compared to the levels observed in membranes from HF-fed rats. These results, as well as the insulin binding data, were similar to those obtained using intact animals. The data presented here indicate that the more rapid growth of the R3230AC mammary tumor seen in intact animals fed high polyunsaturated fat vs fat-free diets did not occur in diabetic animals.     

不同脂肪高脂日粮诱发胰岛素抵抗综合征大鼠模型的比较

目的分析猪油、豆油、氢化椰子油、乳脂四种不同脂肪的高脂日粮分别诱发胰岛素抵抗综合征（IRS）大鼠的血液生化指标差异,为此类模型的建立及实验研究提供参考。方法雄性SD大鼠随机分为5组,对照组给予普通日粮,高脂组给予脂肪热量比相同的高脂日粮。喂养6周,每两周测定空腹血糖、甘油三酯（TG）、高密度脂蛋白胆固醇（HDL-c）、总胆固醇（TC）、胰岛素,根据胰岛素敏感性指数（ISI）=ln1/（FPG×FINS）评定大鼠的胰岛素敏感性。结果6周后,猪油组、乳脂组、豆油组血清胰岛素均显著高于对照组（P〈0.05）;乳脂组血清TG显著高于其它高脂组（P〈0.05）;高脂组血清HDL-c均显著低于对照组（P〈0.05）并以豆油组下降幅度最大;猪油组、乳脂组ISI显著低于对照组（P〈0.05）;而各组间血清总胆固醇、血糖及体重无明显差异（P〉0.05）。结论4种高脂日粮诱发IRS大鼠模型的综合效果依次为乳脂、猪油、豆油、氢化椰子油。     

高脂饲料诱导的肥胖大鼠网膜素水平的实验研究

人群调查发现肥胖人群网膜素水平较正常人群低,而正常及肥胖大鼠血清网膜素水平及其基因表达情况尚不清楚.将SD大鼠随机分为正常组(n=10)和高脂组(n=30),分别喂养普通饲料和高脂饲料.6 w后从高脂组选取体重增长最快的20只,再从中随机抽取10只继续喂养高脂饲料,12 w后两组各剩9只,采用全自动生化仪ADVIA2400测定血糖及血脂、ELISA检测血清胰岛素及网膜素水平、RT-PCR检测网膜脂肪组织网膜素mRNA表达水平.结果显示高脂组大鼠体重、体重增加值、肥胖指数、低密度脂蛋白、胰岛素、血清网膜素水平及网膜脂肪组织网膜素mRNA表达水平均高于正常组(P<0.05).首次发现肥胖大鼠血清网膜素水平及网膜脂肪组织中网膜素mRNA表达水平较正常大鼠显著增高,与人群调查结果不一致.     

Lipidomic Profiling of Di- and Tri-Acylglycerol Species in Weight-Controlled Mice

Weight control by dietary calorie restriction (DCR) or exercise has been shown to prevent cancer in various models. However, the mechanisms as to how weight control is beneficial are not well understood. While previous reports have investigated the effects of weight control on total lipid levels or lipid composition within cellular membranes, there has been little work surrounding changes to individual lipids following weight control interventions. In this study, using a model of skin carcinogenesis centered on the tumor promotion stage, CD-1 mice were randomly assigned into 4 groups: ad libitum and sedentary (control), ad libitum with exercise (AL+Exe), exercise with pair feeding of a diet isocaloric with control (PF+Exe), and sedentary with 20% DCR compared to control. After ten weeks, body weight and body fat percentages significantly decreased in the PF+Exe and DCR groups but not AL+Exe when compared with sedentary controls. Murine skin and plasma samples were obtained for analysis. Lipidomics using electrospray ionization MS/MS was employed to profile triacylglycerol (TG) and diacylglycerol (DG) species. Both plasma and tissue TG species containing fatty acid chains with length 18:1 were significantly decreased following DCR when compared to sedentary control animals. In regards to DG, the most significant changes occurred in the plasma. DG species containing fatty acids with lengths 16:1 or 18:1 were significantly decreased in PF+Exe and DCR groups when compared to sedentary controls. Due to the significant role of TG in energy storage and DG in cellular signaling, our findings of the effects of weight control on individual TG and DG species in plasma and skin tissue following exposure to a tumor promoter, may provide insight into the mechanism of weight control on cancer prevention.     

Effects of clenbuterol on insulin resistance in conscious obese Zucker rats

The present study was conducted to determine the effect of chronic administration of the long-acting beta(2)-adrenergic agonist clenbuterol on rats that are genetically prone to insulin resistance and impaired glucose tolerance. Obese Zucker rats (fa/fa) were given 1 mg/kg of clenbuterol by oral intubation daily for 5 wk. Controls received an equivalent volume of water according to the same schedule. At the end of the treatment, rats were catheterized for euglycemic-hyperinsulinemic (15 mU insulin. kg(-1). min(-1)) clamping. Clenbuterol did not change body weight compared with the control group but caused a redistribution of body weight: leg muscle weights increased, and abdominal fat weight decreased. The glucose infusion rate needed to maintain euglycemia and the rate of glucose disappearance were greater in the clenbuterol-treated rats. Furthermore, plasma insulin levels were decreased, and the rate of glucose uptake into hindlimb muscles and abdominal fat was increased in the clenbuterol-treated rats. This increased rate of glucose uptake was accompanied by a parallel increase in the rate of glycogen synthesis. The increase in muscle glucose uptake could not be ascribed to an increase in the glucose transport protein GLUT-4 in clenbuterol-treated rats. We conclude that chronic clenbuterol treatment reduces the insulin resistance of the obese Zucker rat by increasing insulin-stimulated muscle and adipose tissue glucose uptake. The improvements noted may be related to the repartitioning of body weight between tissues.     

木犀草素预防高脂膳食诱导的小鼠胰岛素抵抗的实验研究

目的:探讨黄酮类成分木犀草素对高脂饮食诱导的肥胖小鼠模型的胰岛素抵抗的影响。方法:30只C57BL/6J小鼠分正常饮食对照组(10只),高脂膳食组(对照组,10只)和高脂膳食加2%木犀草素组(木犀草素组,10只),干预16周,观察体重、血脂水平、血糖、胰岛素敏感性及胰岛素水平的变化。结果:小鼠在给予高脂膳食16周后,体重水平、血脂水平、血糖水平、胰岛素水平显著高于木犀草素组,胰岛素敏感性显著下降,与木犀草素组比较,P<0.05或P<0.01。而木犀草素组则可显著抑制体重、血脂、血糖及胰岛素水平的升高,与胰岛素敏感性未见明显下降,与正常对照组比较,P>0.05。结论:木犀草素可预防高脂膳食诱导的胰岛素抵抗。