银杏叶提取物对糖尿病大鼠肾脏组织型转谷氨酰胺酶表达的影响

目的观察银杏叶提取物对糖尿病大鼠肾脏组织型转谷氨酰胺酶（tTG）表达的影响。方法链脲佐菌素（STZ）复制糖尿病动物模型,将糖尿病动物随机分为,糖尿病组（DM）,银杏叶提取物组（GBE）;另设正常对照组（Con-trol）。逆转录聚合酶链式反应（RT-PCR）检测肾皮质tTG mRNA的表达、Western blot检测肾皮质tTG蛋白表达,PAS染色评估ECM含量。结果与正常对照组比较,糖尿病大鼠肾脏细胞外基质（ECM）积聚,tTG mRNA及蛋白表达均明显增高（P〈0.01）;给予银杏叶提取物可明显减轻ECM积聚,同时tTG表达量也明显降低（P〈0.01）。结论银杏叶提取物可以明显减轻糖尿病大鼠肾脏ECM积聚,提示银杏叶提取物可能通过降低tTG的表达,改善糖尿病肾脏ECM积聚。     

绿原酸对糖尿病大鼠肾脏氧化应激作用的实验研究

目的 探讨绿原酸对糖尿病大鼠肾脏氧化及抗氧化系统的影响.方法 将36只大鼠随机分成N组(正常组)、DM组(糖尿病组)及CA组(绿原酸干预组).DM组和CA组造糖尿痛模型,分别给予腹腔注射生理盐水和绿原酸,饲养10周后,测定血糖、肾脏重量、体重变化,肾皮质超氧化物歧化酶(SOD)、谷胱甘肽过氧化酶(GSH-PX)、丙二醛(MDA)含量及尿微量白蛋白排泄率(UAER).结果 与DM组大鼠相比,CA组大鼠血糖无明显差别,而肾重、体重明显增加,肾皮质SOD、GSH-PX活性明显上升,MDA含量及UAER则明显减少(均P<0.05).结论 绿原酸有改善糖尿病大鼠的一般状况,提高抗氧化能力,抑制氧化应激.减少尿蛋白的作用.     

黄芪多糖对糖尿病大鼠血糖、胰岛素和C肽含量的影响

目的:观察黄芪多糖对糖尿病大鼠血糖、血清胰岛素和C肽含量的影响,初步探讨其抗糖尿病的作用及作用机制. 方法:采用链脲佐菌素55mg·kg-1腹腔注射建立DM大鼠模型,实验分为4组:正常组、DM组、APS低剂量组和APS高剂量组,APS低剂量组和APS高剂量组分别给予APS200、400mg·kg-1·d-1腹腔注射,连续用药6周,ONE TOUCHⅡ尾静脉采血法测定血糖含量,放射免疫分析法检测血清胰岛素和C肽水平.结果:①DM组大鼠的血糖水平较正常组明显升高(P<0.05),血清胰岛素水平和C肽含量明显下降(P<0.05);②APS低剂量组和高剂量组血糖水平较DM组明显降低(P<0.05),但血清胰岛素和C肽含量则没有明显改变(P>0.05).结论:APS可显著降低DM大鼠血糖水平,但对血清胰岛素水平和C肽含量没有显著影响,推测APS治疗糖尿病可能与降低血糖有关,而对胰岛β细胞的分泌功能没有明显影响.     

银杏叶提取物对大鼠脑缺血再灌注后自由基损伤的保护作用

目的 :研究银杏叶提取物 (GBE)对大鼠局灶性脑缺血再灌注后SOD、MDA及NO含量的影响 ,探讨GBE的脑保护作用的机制。方法 :4 0只Wistar雄性大鼠随机分为假手术组 (A)、缺血组 (B)、小剂量GBE组 (C)、大剂量GBE组 (D)。制造大鼠大脑中动脉缺血再灌注模型。C、D组于术前 30min及术后 1h分别给予银杏叶提取物2 0mg/Kg、4 0mg/Kg腹腔内注射。应用TTC染色观察梗死体积、检测脑缺血组织SOD活性、MDA和NO含量。结果 :①SOD活性C、D组明显高于B组 (P <0 .0 1) ,D组高于C组 (P <0 .0 5 )。②MDA和NO含量C、D组明显低于B组(P <0 .0 1) ,D组低于C组 (P <0 .0 5 )。③梗死体积C、D组明显小于B组 (P <0 .0 1) ,D组小于C组 (P <0 .0 5 )。结论 :银杏叶提取物可减少脑缺血再灌注后自由基生成及梗死体积 ,疗效与剂量有关。     

黄芪注射液对糖尿病动物不同器官病理进程的影响

目的探讨黄芪注射液对糖尿病大鼠心、肾、肝、胰腺器官病理改变进程的影响,寻找出黄芪治疗的敏感器官,有针对性地使用该中药制剂进行糖尿病治疗。方法注射使Wistar大鼠建立糖尿病模型,将糖尿病大鼠分为糖尿病组(DM)和黄芪治疗组(RA),另设一正常组动物。黄芪治疗组动物每天给予黄芪注射液腹腔注射3.3 ml/kg,糖尿病组动物每天给予生理盐水腹腔注射3.3 ml/kg,连续注射30天,观察各组大鼠肝脏、肾脏、心脏和胰腺形态的变化。结果 RA治疗7 d、14 d、30 d和60 d时,RA组和DM组大鼠的肝脏、肾脏和心脏的病理改变没有显著的差异,与正常大鼠的组织结构相似。30 d时,DM组大鼠的胰腺的病理改变明显,胰腺内有较多的炎细胞浸润,并且细胞数目减少。RA治疗60天时,RA组和DM组大鼠肝脏、心脏的病理组织改变不明显,与正常大鼠的组织结构相似。与RA组相比较,60 d时,DM组大鼠肾脏和胰腺的病理改变明显,胰岛内细胞松散明显,细胞数明显减少,细胞核大小不一,半数细胞内可见明显的空泡,可见明显的炎细胞浸润。RA治疗组大鼠的肾脏和胰腺的病理组织改变不明显,与正常大鼠的组织结构相似。结论 RA能够延缓或阻止STZ诱导的糖尿病大鼠组织器官的病理进程。     

银杏叶提取物减轻糖基化终末产物对大鼠肾脏TGF-β及CTGF表达的影响

目的观察银杏叶提取物对糖基化终末产物（AGEs）引起的大鼠肾脏TGF-β及CTGF过表达的影响。方法每日给正常大鼠尾静脉注射AGE-修饰大鼠血清蛋白（AGEs组）,部分大鼠同时灌胃给予银杏叶提取物（GBE组）,注射天然大鼠血清蛋白（RSP组）和不施加处理的正常大鼠（空白对照组）作为对照。Elisa法检测肾皮质TGF-β及CTGF蛋白的表达,RT-PCR检测TGF-β及CTGF mRNA的表达。结果与RSP组及空白对照组比较,AGEs组大鼠尿蛋白含量明显增加（P〈0.05）,TGF-β及CTGF蛋白、mRNA的表达均增高（P〈0.01）,给予GBE后尿蛋白含量明显降低（P〈0.01）,TGF-β及CTGF蛋白含量及mRNA表达均明显降低（P〈0.05,P〈0.01）。结论 GBE改善AGEs引起的肾功能变化,减轻AGEs诱导的大鼠肾皮质TGF-β及CTGF过表达。提示GBE可通过抑制AGEs引起的TGF-β及CTGF过表达而在糖尿病中起到肾脏保护作用。     

银杏叶提取物对糖尿病肾病的防治作用与机制研究

目的:观察银杏叶提取物(GBE)对糖尿病肾病大鼠核转录因子-κB(NF-κB)活性、肿瘤坏死因子-α(TNF-α)和白细胞介素-6(IL-6)水平的影响,探讨其对糖尿病肾病的防治作用及其机制.方法:22只Wistar大鼠分为正常对照组(A组),糖尿病无干预组(B组),GBE干预组(C组).以一次性腹腔注射链脲佐菌素60 mg/kg制备糖尿病大鼠模型.12周后取肾组织进行病理学观察,以电泳迁移率变动分析法检测肾组织NF-κB活性,放射免疫法测定血清TNF-α和IL-6水平.结果:B、C组大鼠饲养过程中各死亡2只,存活大鼠空腹血糖>13.9 mmol/L,模型制作成功.B组肾小球基底膜厚度、肾小球内细胞数和单个核细胞数显著多于A组,C组显著少于B组而多于A组(P均<0.05).与A组比较,B组肾组织NF-κB活性、TNF-α和IL-6水平均显著升高,C组也有升高但明显低于B组(P均<0.05).TNF-α、IL-6水平与NF-κB活性呈正相关(r1=0.83,r2=0.78;P均<0.05).结论:银杏叶提取物可以通过抑制肾组织中NF-κB的活化、减轻过度的炎症反应而延缓糖尿病肾病的发生、发展.     

银杏叶提取物抑制Bcl-2表达后对糖尿病心肌病的影响

目的探讨银杏叶提取物(GBE)对链脲佐菌素(STZ)大鼠糖尿病心肌病(DCM)后的作用,阐明银杏叶提取物对STZ大鼠糖尿病心肌病后Bcl-2表达的影响。方法 40只雄性Wistar大鼠分对照组(10只)、模型组(10只)、阳性药组(10只)和治疗组(10只)。观察GBE干预STZ大鼠心肌损伤后,大鼠体质量、血糖、形态学及Bcl-2蛋白表达。结果对照组体重高于模型组(P0.05)。暴露于GBE后,模型组大鼠体重增高(P0.05);模型组Bcl-2的蛋白表达水平较正常组降低(P0.05),而治疗组较模型组升高(P0.05)。结论 GBE可能增强STZ诱导的大鼠糖尿病心肌病中Bcl-2的表达,进而调控心肌的损害。     

普罗布考对2型糖尿病大鼠胰岛功能的干预作用

目的探讨抗氧化剂普罗布考对2型糖尿病大鼠胰岛细胞氧化应激和胰岛分泌功能的影响。方法选择6周龄雄性Wistar大鼠24只,随机分为3组,每组8只:正常对照组,糖尿病组和普罗布考组。采用高脂饲料喂养加小剂量链脲佐菌素腹腔注射的方法建立2型糖尿病大鼠模型。普罗布考组给予普罗布考500mg/(kg·d),早晚各1次,灌胃1个月。应用葡萄糖氧化酶法﹑酶终点法﹑放射免疫法连续多次检测大鼠空腹血糖(FBG)和餐后2h血糖(PBG)、甘油三酯(TG)、总胆固醇(T-ch)以及空腹胰岛素(FINS)水平,胰腺组织匀浆检测丙二醛(MDA)、一氧化氮(NO)、超氧化物歧化酶(SOD)及谷胱甘肽过氧化物酶(GSH-Px)含量。应用免疫组化法检测胰岛素表达变化。结果与正常对照组比较,糖尿病组大鼠胰腺匀浆MDA、NO含量升高,SOD、GSH-Px含量降低,胰岛素表达明显降低,差异均有统计学意义(P均0.05);与糖尿病组比较,普罗布考组大鼠胰腺匀浆MDA、NO含量降低,SOD、GSH-Px含量升高,胰岛素表达升高,胰岛素分泌功能明显增强(P均0.05)。结论抗氧化剂可提高2型糖尿病大鼠胰腺对抗氧化应激能力,增强2型糖尿病大鼠胰岛细胞内分泌功能。     

银杏叶对大鼠脊髓缺血再灌注损伤保护作用的实验研究

目的探讨预先给予银杏叶提取物能否预防大鼠脊髓缺血再灌注损伤。方法将30只大鼠随机分为3组,假手术组(S组)、缺血再灌注组(IR组)、银杏叶提取物保护组(G组)。其中G组每日腹腔注射给予0.83 ml.kg-1GBE,连续给药5天。采用腹主动脉缺血法制备大鼠的脊髓缺血再灌注损伤模型。缺血45 min,再灌注24 h后进行Tarlov神经功能评价和病理组织学改变的观察。结果 G组与IR组相比较,神经功能评分结果显示IR组后肢神经功能改善明显,神经功能评分结果差异具有显著的统计学意义(P0.05)。病理组织学结果表明,IR组出现明显的病理改变,神经细胞固缩、组织内血管充血等病理改变,G组的病理改变较轻,明显好于IR组。结论银杏叶对大鼠脊髓缺血再灌注损伤具有明显的保护作用。     

PKCβ inhibition with ruboxistaurin reduces oxidative stress and attenuates left ventricular hypertrophy and dysfunction in rats with streptozotocin-induced diabetes

Oxidative stress plays critical roles in the development of diabetic cardiovascular complications, including myocardial hypertrophy. The β isoform of PKC (protein kinase C) is preferentially overexpressed in the myocardium of diabetic subjects accompanied with increased activation of the pro-oxidant enzyme NADPH oxidase, which may exacerbate oxidative stress. We hypothesized that myocardial PKCβ is a major upstream mediator of oxidative stress in diabetes and that PKCβ inhibition can attenuate myocardial hypertrophy and dysfunction. Control or streptozotocin-induced diabetic rats were treated with the selective PKCβ inhibitor RBX (ruboxistaurin; 1?mg/kg of body weight per day) or the antioxidant NAC (N-acetylcysteine) for 4?weeks. LV (left ventricular) dimensions and functions were detected by echocardiography. 15-F2t-isoprostane (a specific index of oxidative stress) and myocardial activities of superoxide dismutase as well as protein levels of NADPH oxidase were assessed by immunoassay or Western blotting. Echocardiography revealed that the LV mass/body weight ratio was significantly increased in diabetic rats (P<0.01 compared with the control group) in parallel with the impaired LV relaxation. A significant increase in cardiomyocyte cross-sectional area was observed in diabetic rats accompanied by an increased production of O2- (superoxide anion) and 15-F2t-isoprostane (all P<0.05 compared with the control group). RBX normalized these changes with concomitant inhibition of PKCβ2 activation and prevention of NADPH oxidase subunit p67phox membrane translocation and p22phox overexpression. The effects of RBX were comparable with that of NAC, except that NAC was inferior to RBX in attenuating cardiac dysfunction. It is concluded that RBX can ameliorate myocardial hypertrophy and dysfunction in diabetes, which may represent a novel therapy in the prevention of diabetic cardiovascular complications.     

Effects of melatonin on plasma oxidative stress in rats with streptozotocin induced diabetes.

The aim of this study was to evaluate the effect of single melatonin injection on plasma oxidative stress in rats with streptozotocin induced diabetes. Diabetes was induced after a single intraperitoneal dose of streptozotocin (60 mg/kg), while hyperglycemia was determined 10 days upon injection. Diabetic rats were divided into two groups. In the first group the injection of melatonin was applied intraperitoneally (20 mg/kg), while the second group received physiological solution. Twenty-four hours later the rats were killed and their blood was centrifuged. In the rat plasma the following parameters were evaluated: the glucose level, superoxide radical, lipid peroxidation, reduced glutathione, total antioxidant capacity, antioxidant enzymes and the aldose reductase activity. The injected melatonin decreased the superoxide radical in the rat plasma. Moreover, melatonin increased the total antioxidative capacity and the activity of antioxidative enzymes superoxide dismutase and glutathione peroxidase. These results indicate that melatonin is a strong scavenger, which may diminish negative effects of oxidative stress in diabetic rats 24 hours after its application The findings suggest that melatonin is also a strong antioxidant. It increases the antioxidant enzymes activity, inhibiting the release of superoxide radicals. A high total antioxidative capacity and the lower activity of aldose reductase enlarge melatonin scavenger capacity against reactive oxygen species in diabetic rats.     

高血糖对大鼠肾皮质葡萄糖转运蛋白1 mRNA表达的影响

【摘要】目的探讨葡萄糖转运蛋白1（glucosetransporter1,GLUT1）在糖尿病。肾病（diabeticnephropathy,DN）发病机制中的作用。方法将36只Wistar大鼠随机分为对照组10只、高血糖组及2型糖尿病组各13只,分别采用腹腔内注射链脲佐菌素及高脂饮食加腹腔内注射链脲佐菌素方法制备高血糖及2型糖尿病模型。10W末实验结束后,取大鼠肾皮质,同时检测大鼠体重、肾重、肾重百分比,血清BUN;采用逆转录聚合酶链反应半定量分析肾皮质GLUT1 mRNA的表达。结果高血糖组大鼠的体重显著降低,肾重、肾重百分比、BUN、FPG和ISI水平均高于2型糖尿病组及对照组．差异均有统计学意义（P〈0．05）。而FINS的水平低于2型糖尿病组及对照组,差异亦均有统计学意义（P均〈0．05）。高血糖组和2型糖尿病组GLUTlmRNA在‘肾皮质中的表达均显著高于对照组．且高血糖组GLUT1mR．NA在肾皮质的表达显著高于2型糖尿病组（P均〈0．05）。结论GLUT1在肾皮质中有表达．高血糖可以上调肾皮质GLUT1表达,GLUT1可能与DN的发病相关。     

柚皮素对糖尿病视网膜病变大鼠氧化损伤、细胞凋亡及Nrf2-ARE的影响

目的探讨柚皮素对糖尿病视网膜病变(DR)大鼠氧化损伤、细胞凋亡及核因子E2相关因子2(Nrf2)-抗氧化反应元件(ARE)的影响。方法随机数字表法将健康雄性SD大鼠分为空白对照组、模型组、阳性对照组、低剂量柚皮素组、中剂量柚皮素组、高剂量柚皮素组。采用腹腔注射链脲佐菌素(STZ)法建立DR大鼠模型。阳性对照组灌胃150 mg·kg^-1·d^-1羟苯磺酸钙,低、中、高剂量柚皮素组分别灌胃25 mg·kg^-1·d^-1、50 mg·kg^-1·d^-1、100 mg·kg^-1·d^-1柚皮素,空白对照组和模型组灌胃1%二甲基亚砜(DMSO),连续灌胃60 d。取各组大鼠视网膜组织,试剂盒检测丙二醛(MDA)含量、超氧化物歧化酶(SOD)和谷胱甘肽还原酶(GSH-Px)活力,TUNEL染色法检测视网膜组织的神经节细胞凋亡情况,Western blot法检测核因子E2相关因子2(Nrf2)、醌氧化还原酶-1(NQO1)和血红素加氧酶-1(HO-1)蛋白表达。结果与空白对照组比,模型组大鼠视网膜组织MDA含量、细胞凋亡指数显著升高(P<0.05),SOD和GSH-Px活力、Nrf2、HO-1、NQO1蛋白表达显著降低(P<0.05)。与模型组比,中、高剂量柚皮素组和阳性对照组大鼠视网膜组织MDA含量、细胞凋亡指数显著降低(P<0.05),SOD和GSH-Px活力、Nrf2、HO-1、NQO1蛋白表达显著降低显著升高(P<0.05),但低剂量组各指标均无显著差异(P>0.05)。结论柚皮素可能通过激活Nrf2-ARE信号通路降低糖尿病视网膜病变大鼠氧化应激损伤,其作用呈剂量依赖性。     

Sesame oil protects against lipopolysaccharide-stimulated oxidative stress in rats

OBJECTIVE: The aim of this study was to determine the effects and the defense mechanisms of sesame oil on lipopolysaccharide-induced oxidative stress in rats. DESIGN: Laboratory in vivo study of the effect of sesame oil on lipid peroxide, superoxide anion, superoxide dismutase, catalase, glutathione, and nitrite concentrations. To assess the effect of sesame oil on hepatic function, we determined serum aspartate aminotransferase, total bilirubin, and liver histology. SETTING: University laboratory. SUBJECTS: Male SPF Wistar rats. INTERVENTIONS: Blood testing, administration of oils, and liver biopsies. MEASUREMENTS AND MAIN RESULTS: Oxidative stress induced by lipopolysaccharide (5 mg/kg, intraperitoneally) was assessed by determination of lipid peroxidation. Sesame oil was given orally immediately after lipopolysaccharide administration, and lipid peroxidation concentrations were determined. The reactive oxygen species superoxide anion was measured by chemiluminescence analyzer. The enzyme activities of superoxide dismutase and catalase and the concentrations of glutathione and nitrite also were determined. Hepatic injury was evaluated by determining the concentrations of serum aspartate aminotransferase and total bilirubin and by liver histologic examination. Sesame oil significantly reduced lipid peroxidation but failed to affect nitrite concentrations in lipopolysaccharide-treated rats. Superoxide anion counts were decreased, and glutathione, but not superoxide dismutase or catalase, was increased in sesame oil-treated groups with lipopolysaccharide-induced oxidative stress. Only sesame oil-treated groups, but not corn oil- or mineral oil-treated groups, showed attenuated hepatic disorder induced by lipopolysaccharide. In addition, sesame oil given 6 hrs after lipopolysaccharide also attenuated lipid peroxidation and hepatic disorder. Furthermore, sesame oil given immediately or 6 hrs after lipopolysaccharide administration significantly reduced morphologic changes induced by lipopolysaccharide. CONCLUSION: A single dose of sesame oil may attenuate oxidative stress and subsequently relieve hepatic disorder in endotoxemic rats.     

乌司他丁对百草枯中毒大鼠氧化应激及核因子κB的影响

目的观察急性百草枯（PQ）中毒大鼠氧化应激及肺组织核因子-κB（NF-κB）的变化,探讨乌司他丁（UTI）的治疗机制。方法将72只SD大鼠按随机数字表法分为A、B、C 3组,每组各24只。B、C组PQ灌胃（80 mg·kg^-1）染毒建立SD大鼠肺损伤模型;A组生理盐水1 mL灌胃。C组于PQ灌胃后30 min腹腔内注射UTI 10 U·kg^-1·d^-1;A、B组腹腔注射等量生理盐水。注射后12、24、48、72 h观察3组大鼠肺组织病理改变;测定血清中丙二醛（MDA）含量及谷胱甘肽过氧化物酶（GSH-Px）、超氧化物歧化酶（SOD）的变化;计算肺湿/干重比（W/D）及肺组织中NF-κB p65 mRNA的表达。结果肺组织病理变化：B、C组PQ中毒后肺泡壁充血、炎性细胞浸润,并有局灶性出血;A组无明显变化。MDA含量：B、C组各时间点明显高于A组,C组较B组明显降低（P〈0.05或P〈0.01）。SOD、GSH-Px：B组各时间点较A组明显下降（P〈0.01）,C组较B组明显升高（P〈0.05或P〈0.01）。NF-κB p65 mRNA表达：B、C组肺组织表达明显高于A组（P〈0.05或P〈0.01）,C组明显低于B组（P〈0.01）。肺W/D：B、C组各时间点较A组明显增强（P〈0.05或P〈0.01）,C组较B组明显下降（P〈0.05）。结论氧化应激及NF-κB活化是参与PQ中毒肺损伤的重要因素;UTI能纠正氧化还原失衡,抑制NF-κB活化,减轻PQ中毒大鼠的肺损伤。     

筋脉通对糖尿病大鼠背根神经节氧化应激的影响

  目的  探讨中药复方筋脉通对糖尿病大鼠背根神经节尼氏染色及NADPH氧化酶、诱导型一氧化氮合酶(inducible nitric oxide synthase, iNOS)表达的影响。  方法  70只雄性Sprague Dawley大鼠腹腔注射链脲佐菌素诱导糖尿病大鼠模型后, 随机分为模型组、筋脉通大、中、小剂量组和维生素C对照组, 每组14只, 同时设正常对照组(n=10);筋脉通大、中、小剂量组分别按成人剂量20倍、10倍、5倍、维生素C组按成人剂量10倍灌胃给药, 模型组和正常对照组予等量蒸馏水灌胃; 16周后对各组背根神经节切片行尼氏染色, 免疫组化法检测NADPH氧化酶p22 phox亚基和iNOS的表达。  结果  模型组神经元胞体中尼氏体缺失, 筋脉通大、中剂量组尼氏体改变明显轻于模型组; 筋脉通各剂量组NADPH氧化酶p22 phox亚基、iNOS表达均明显低于模型组(P < 0.05)。  结论  糖尿病大鼠周围感觉神经节存在氧化应激反应, 筋脉通可减轻氧化应激损伤, 保护神经元。