牛磺酸对链脲佐菌素糖尿病大鼠胰岛β细胞的保护作用

利用链脲佐菌素诱导的Wistar糖尿病大鼠观察牛磺酸对其的防治作用。结果表明：①正常大鼠口服牛磺酸（8g·kg-1／d）对血糖和血清胰岛素浓度无明显影响；②糖尿病大鼠服用牛磺酸后可明显抑制其高血糖效应（P＜0．05，0．01，0．001）；③对链脲佐菌素诱致的大鼠血清胰岛素浓度的降低，牛磺酸具有明显的反转作用（P＜0．05，0．01，0．001）；④免疫组化结果表明，经牛磺酸防治的糖尿病大鼠表达胰岛素的胰岛数量较对照组显著增多（P＜0．05）。提示牛磺酸具有对抗和修复链脲佐菌素所引起的大鼠胰岛β细胞损伤的作用。     

青钱柳对链脲佐菌素诱导大鼠胰岛细胞损伤的保护作用

目的 探讨青钱柳对链脲佐菌素(STZ)诱导的大鼠胰岛细胞损伤的保护作用。方法 60只大鼠,随机选取10只为正常组,其余1次性腹腔注射STZ建立大鼠糖尿病模型后随机分为模型组,青钱柳低、中、高剂量组和罗格列酮药物组。持续给药4 w,测定空腹血糖值、流式细胞仪测定胰岛细胞凋亡情况、荧光分光光度计法测定半胱氨酸蛋白酶(Caspase)-3的含量及Western印迹法测定B细胞淋巴瘤(Bcl)-2相关X蛋白(Bax)和Bcl-2蛋白表达。结果 青钱柳可显著改善STZ诱导的大鼠糖尿病症状,抑制胰岛细胞的凋亡及Caspase-3和Bax蛋白表达,促进Bcl-2蛋白表达,与模型组比较具有显著性差异(P<0.05,P<0.01)。结论 青钱柳具有抗STZ诱导的大鼠胰岛细胞凋亡作用,其主要作用机制与抑制凋亡相关蛋白表达有关。     

通络方药对糖尿病大鼠胰岛β细胞的保护作用

目的研究通络方药（TLR）对链脲佐菌素（STZ）所致大鼠胰岛β细胞损伤的保护作用。方法建立糖尿病大鼠模型前8天开始给予TLR直至实验结束。实验结束时测血糖、体重;取胰腺测定胰腺匀浆中丙二醛（MDA）及谷胱甘肽过氧化物酶（GSH-Px）水平,透射电镜检测胰岛口细胞。结果与正常组相比,STZ组胰腺内MDA水平明显升高（P〈0．05）,GSH—Px活性明显降低（P〈0．05）,血糖明显升高。TLR预处理明显降低STZ组大鼠的血糖水平,同时降低大鼠胰腺匀浆内MDA含量（P〈0．05）,升高GSH—Px活性（P〈0．05）。透射电镜显示TLR预处理使胰岛β细胞的损伤明显减轻。结论TLR通过减轻胰腺内氧化应激水平保护胰岛β细胞完整并有效防止STZ诱导的糖尿病发生。     

对链脲佐菌素诱导的糖尿病大鼠壁细胞和G细胞的体视学研究

采用ＨＥ染色和免疫组化方法结合生物体视学技术，对链脲佐菌素诱导的糖尿病大鼠在胃底腺的壁细胞和幽门部胃粘膜的Ｇ细胞进行立体计量研究。结果显示：糖尿病状态的早期，壁细胞和Ｇ细胞的体积均明显增大，数量却显著减少。根据正常情况下壁细胞和Ｇ细胞的细胞动力学变化、胃泌素的生物学作用和上述实验结果，认为大鼠胃底腺峡部的干细胞向壁细胞分化成熟的功能及Ｇ细胞的分裂增殖活动，在胰岛素缺乏的情况下受到一定程度的抑制，而这种功能的抑制是糖尿病状态下易出现胃粘膜萎缩、胃酸分泌减少和胃轻瘫的重要原因之一。     

链脲佐菌素诱导的糖尿病大鼠壁细胞和G细胞的超微结构改变

继本实验室对链脲佐菌素 (streptozotocin,STZ)诱导的糖尿病大鼠的壁细胞和 G细胞进行立体计量研究之后 [1 ] ,我们对糖尿病大鼠壁细胞和 G细胞的超微结构又进行了观察 ,现报告如下。材料和方法将 12只月龄为 8周左右的雄性 Wistar大鼠随机分为糖尿病组和对照组 ,每组 6只。糖尿病组按 5 0 mg/ kg腹腔内一次注射 STZ(Sigma Chemical Co,L ouis,USA)溶液 ;对照组大鼠腹腔内注射相同剂量的溶剂 ;然后分笼饲养 ,自由进食和饮水。每日监测每只大鼠尿糖的变化 ,每周使用 One Touch 血糖仪测血糖一次。于有效建立糖尿病状态的第 2 1天 ,…     

链脲佐菌素糖尿病大鼠的肝脏损伤

本实验旨在通过建立链脲佐菌素(STZ)糖尿病大鼠模型,观察该实验模型的肝脏损伤,并探讨其可能的相关因素。     

α-硫辛酸抑制IκB激酶β对胰岛细胞的影响

目的 探讨脂肪细胞对共培养体系中胰岛细胞炎症状态的影响,以及α-硫辛酸对抗胰岛细胞炎症反应的作用.方法 以单纯胰岛细胞培养为对照组、胰岛细胞-脂肪细胞共培养为实验组、胰岛细胞-脂肪细胞共培养加α-硫辛酸为干预组.以胰岛素释放试验比较胰岛细胞的功能,采用实时荧光PCR和Western印迹法检测细胞内IκB激酶(IKK)B的mRNA和蛋白水平.结果 实验组胰岛索释放试验的分泌指数明显低于对照组和干预组(1.0±0.1vs2.6±0.2和2.5±0.5,P<0.01).实时荧光PCR显示,实验组的IKKβ mRNA水平明显高于对照组和干预组(4.62±0.60 vs 1.00±0.46和2.25±O.75,P相似文献   

烟酰胺对链脲佐菌素引致糖尿病的防治作用

３０只ＳＤ大鼠随机分成三组，在给在鼠腹腔注射链脲佐菌素为３天，分别予以生理盐水喂服、烟酰胺喂服和肌注，并连续用药两周。结果表明烟酰胺对链脲佐菌素引致糖尿病有较好的防治作用。     

链脲佐菌素糖尿病大鼠痛阈的变化

链脲佐菌素糖尿病大鼠痛阈的变化张巧俊，赵英贤，刘健糖尿病性神经病通常伴有对痛刺激的敏感性升高、感觉异常和其它的神经功能障碍［１］。本实验采用行为学方法，对大鼠腹腔注射链脲佐菌素（ＳＴＺ）后，对非伤害性温度刺激（１０～４２℃）、伤害性温度刺激（甩尾反射...     

原花青素对STZ致胰岛细胞损伤的保护作用

目的 探讨原花青素(PC)对链脲佐菌素(STZ)损伤大鼠胰岛素瘤细胞(INS-1)的保护作用.方法 INS-1细胞培养24 h后,以链脲佐菌素(STZ)损伤细胞,将细胞分为正常对照组、STZ组、PC保护组(PC +STZ),PC保护组培养液中加入不同浓度的PC干预12h后,用MTT比色法测定细胞存活率,用放免法检测培养细胞上清液胰岛素分泌量的变化,用比色法测定培养细胞上清液丙二醛( MDA)和超氧化物歧化酶(SOD)等指标的变化.结果 PC可以减少STZ对INS-1细胞的损伤,PC保护组的INS-1细胞存活率增加(P＜0.01);与STZ组比较,PC保护组促进了INS-1细胞的胰岛素分泌(P＜0.01),降低了INS-1细胞的MDA含量(P＜0.01),增强了T-AOC的活性(P＜0.01).结论 原花青素对STZ损伤INS-1细胞有一定的保护作用,其机制可能是通过降低MDA生成,提高T-AOC能力有关.     

依达拉奉对大鼠急性坏死性胰腺炎的保护作用

目的:探讨自由基清除剂依达拉奉对大鼠急性坏死性胰腺炎的保护作用及其机制.方法:90只♂SD大鼠随机分为假手术组(SHAM组)、坏死性胰腺炎组(ANP组)、依达拉奉治疗组(EDA组),每组30只.SHAM组为开腹后只翻动十二指肠及胰腺后关腹;ANP组胰胆管内逆行输注1.5%脱氧胆酸钠制备急性坏死性胰腺炎模型;EDA组为ANP造模后立即尾静脉注射依达拉奉(6mg/kg).分别于术后6、12、24h处死大鼠(每个时点10只),观察胰腺病理形态改变并评分;检测血清淀粉酶、TNF-α、ET-1、sICAM-1含量;检测胰腺组织中丙二醛(MDA)含量及总超氧化物歧化酶(T-SOD)活力.结果:与ANP组比较,EDA治疗组在胰腺病理改变、血清TNF-α水平(6h:109.6ng/L±49.0ng/Lvs190.2ng/L±46.6ng/L,12h:405.4ng/L±116.3ng/Lvs559.7ng/L±203.9ng/L,24h:415.4ng/L±164.6ng/Lvs648.7ng/L±222.1ng/L,均P<0.05)、血清ET-1水平(6h:45.6ng/L±13.5ng/Lvs66.0ng/L±16.0ng/L,12h:83.5ng/L±15.4ng/Lvs96.8ng/L±23.0ng/L,24h:85.1ng/L±25.8ng/Lvs103.9ng/L±28.9ng/L),血清sICAM-1水平(6h:0.58ng/L±0.13ng/Lvs0.78ng/L±0.14ng/L,12h:0.78ng/L±0.10ng/Lvs0.94ng/L±0.12ng/L,24h:0.96ng/L±0.16ng/Lvs1.24ng/L±0.30ng/L,均P<0.05)、胰腺组织MDA含量(6h:4.22nmol/mgprot±0.40nmol/mgprotvs8.79nmol/mgprot±0.80nmol/mgprot,12h:5.90nmol/mgprot±0.51nmol/mgprotvs12.30nmol/mgprot±1.02nmol/mgprot,24h:9.10nmol/mgprot±0.84nmol/mgprotvs17.88nmol/mgprot±1.43nmol/mgprot)均有不同程度减轻(均P<0.05),T-SOD活力增强(6h:88.6U/mgprot±7.1U/mgprotvs68.8U/mgprot±10.5U/mgprot,12h:77.6U/mgprot±6.8U/mgprotvs46.0U/mgprot±8.9U/mgprot,24h:45.5U/mgprot±5.3U/mgprotvs27.8U/mgprot±4.3U/mgprot,均P<0.05);血清淀粉酶变化无显著差异.与SHAM组比较,ANP组胰腺组织病理评分、血清淀粉酶、TNF-α、ET-1、sICAM-1明显升高,胰腺组织MDA含量升高,T-SOD活力下降,差异均有统计学意义.结论:依达拉奉可以清除坏死性胰腺炎体内过量生成的氧自由基并减少炎性因子的表达,减轻胰腺组织损伤.     

Oxidative stress in diabetic rats induced by streptozotocin: Protective effects of melatonin

Abstract: We have studied the effect of the administration of two doses of melatonin (melatonin 100 and melatonin 200 μg/kg bw) on diabetes and oxidative stress experimentally induced by the injection of streptozotocin (STZ) in female Wistar rats. STZ was injected as a single dose (60 mg/kg i.p. in buffered citrate solution, pH 4.0) and melatonin (melatonin 100, 100 μg/kg/day i.p.; melatonin 200, 200 μg/kg/day i.p.) beginning 3 days before diabetes induction and continuing until the end of the study (8 weeks). The parameters analysed to evaluate oxidative stress and the diabetic state were a) for oxidative stress, changes of lipoperoxides (i.e., malondialdehyde, MDA) in plasma and erythrocytes and the changes in reduced glutathione (GSH) in erythrocytes and b) for diabetes, changes in glycemia, lipids (triglycerides: TG; total cholesterol: TC; HDL-cholesterol, HDL-c), percentage of glycosylated hemoglobin (Hb%), and plasma fructosamine. The injection of STZ caused significant increases in the levels of glycemia, percentage of glycosylated hemoglobin, fructosamine, cholesterol, triglycerides, and lipoperoxides in plasma and erythrocytes, whereas it decreased the levels of HDL-c and the GSH content in erythrocytes. The melatonin 100 dose reduced significantly all these increases, except the percentage of glycosylated hemoglobin. With regard to the decreases of plasma HDL-c and GSH content in erythrocytes, this melatonin dose returned them to normal levels. The melatonin 200 dose produced similar changes, though the effects were especially noticeable in the decrease of glycemia (55% vs. diabetes), percentage of hemoglobin (P < 0.001 vs diabetes), and fructosamine (31% vs. diabetes). This dose also reversed the decreases of HDL-c and GSH in erythrocytes. Both doses of melatonin caused significant reduction of the percentage of glycosylated hemoglobin in those groups that were non-diabetic. These illustrate the protective effect of melatonin against oxidative stress and the severity of diabetes induced by STZ. In particular, this study confirms two facts: 1) the powerful antioxidant action of this pineal indole and 2) the importance of the severity of oxidative stress to maintain hyperglycemia and protein glycosylation, two pathogenetic cornerstones indicative of diabetic complications. Melatonin reduces remarkably the degree of lipoperoxidation, hyperglycemia, and protein glycosylation, which gives hope to a promising perspective of this product, together with other biological antioxidants, in the treatment of diabetic complications where oxidative stress, either in a high or in a low degree, is present.     

α-硫辛酸对2型糖尿病氧化应激状态和内皮功能的影响

目的观察α-硫辛酸对2型糖尿病患者氧化应激状态及血管内皮功能的影响。方法30例2型糖尿病患者每日给予α-硫辛酸600mg,治疗2周,检测治疗前后氧化还原系统指标、全血Na -K -ATP酶活力以及血流介导的内皮依赖性血管舒张功能。结果治疗后患者血清丙二醛含量降低、超氧化物歧化酶活力增高,差异有非常显著性(P<0.01),谷胱甘肽、维生素E含量增加,Na -K -ATP酶活力增强,血流介导的内皮依赖性的血管舒张功能增强,但差异无显著性(P>0.05),总体症状评分明显下降(P<0.01)。结论抗氧化剂α-硫辛酸治疗能改善2型糖尿病患者氧化应激状态及血管内皮功能,缓解临床症状。     

抗氧化剂α-硫辛酸对2型糖尿病大鼠肾脏的保护作用

2型糖尿病模型Goto Kakisaki大鼠12周出现尿蛋白排泄率增高，肾脏氧化应激指标异常，肾组织NF-κB、p22phox和p47phox表达上调，肾组织形态学改变明显，肾组织丙二醛与p22phox、p47phox和NF-κB呈显著正相关，而隔日腹腔内注射1次硫辛酸（35mg／kg）治疗可减轻上述异常变化，表明硫辛酸通过抗氧化作用而对这一类型糖尿病大鼠肾脏具有保护效应。     

Cytoprotective effects of amifostine,ascorbic acid and N-acetylcysteine against methotrexate-induced hepatotoxicity in rats

AIM:To investigate the potential role of oxidative stress and the possible therapeutic effects of N-acetyl cysteine(NAC),amifostine(AMF)and ascorbic acid(ASC)in methotrexate(MTX)-induced hepatotoxicity.METHODS:An MTX-induced hepatotoxicity model was established in 44 male Sprague Dawley rats by administration of a single intraperitoneal injection of20 mg/kg MTX.Eleven of the rats were left untreated(Model group;n=11),and the remaining rats were treated with a 7-d course of 50 mg/kg per day NAC (MTX+NAC group;n=11),50 mg/kg per single dose AMF(MTX+AMF group;n=11),or 10 mg/kg per day ASC(MTX+ASC group;n=11).Eleven rats that received no MTX and no treatments served as the negative control group.Structural and functional changes related to MTX-and the various treatments were assessed by histopathological analysis of liver tissues and biochemical assays of malondialdehyde(MDA),superoxide dismutase(SOD),catalase,glutathione(GSH)and xanthine oxidase activities and of serum levels of aspartate aminotransferase,alanine aminotransferase,alkaline phosphatase and total bilirubin.RESULTS:Exposure to MTX caused structural and functional hepatotoxicity,as evidenced by significantly worse histopathological scores[median(range)injury score:control group:1(0-3)vs 7(6-9),P=0.001]and significantly higher MDA activity[409(352-466)nmol/g vs 455.5(419-516)nmol/g,P<0.05].The extent of MTX-induced perturbation of both parameters was reduced by all three cytoprotective agents,but only the reduction in hepatotoxicity scores reached statistical significance[4(3-6)for NAC,4.5(3-5)for AMF and 6(5-6)for ASC;P=0.001,P=0.001 and P<0.005vs model group respectively].Exposure to MTX also caused a significant reduction in the activities of GSH and SOD antioxidants in liver tissues[control group:3.02(2.85-3.43)μmol/g and 71.78(61.88-97.81)U/g vs model group:2.52(2.07-3.34)μmol/g and 61.46(58.27-67.75)U/g,P<0.05];however,only the NAC treatment provided significant increases in these antioxidant enzyme activities[3.22(2.54-3.62)μmol/g and 69.22(61.13-100.88)U/g,P<0.05 and P<0.01vs model group respectively].CONCLUSION:MTX-induced structural and functional damage to hepatic tissues in rats may involve oxidative stress,and cytoprotective agents(NAC>AMF>ASC)may alleviate MTX hepatotoxicity.     

Protective effects of D-002 on experimentally induced gastroesophageal reflux in rats

AIM:To investigate the effects of beeswax alcohols(D-002)on the esophageal damage induced by gastroesophageal reflux(GER)in rats.METHODS:Sixty male rats were randomized into six groups(10 rats/group):a negative control and five groups with experimentally induced GER:a positive vehicle control,three treated with D-002(25,100 and 200mg/kg,respectively),and one with omeprazole 10 mg/kg.All treatments were given by gastric gavage.One hour after dosing,GER was produced by simultaneous ligation of the pyloric end and the forestomach.Esophageal lesions index(ELI),gastric secretion volume and acidity,and esophageal malondialdehyde(MDA)and sulfhydryl(SH)group concentrations were measured.Statistical significance was considered at P<0.05.RESULTS:As compared to the negative control,the positive control group exhibited increased ELI(5.2±0.33 vs 0±0,P=0.0003),gastric secretion volume(2.69±0.09 vs 0.1±0.0,P=0.0003)and acidity(238±19.37 vs 120.0±5.77,P=0.001),and esophageal concentrations of MDA(2.56±0.1 vs 1.76±0.28,P=0.001)and SH groups(1.02±0.05 vs 0.56±0.08,P=0.0003).D-002(25,100 and 200 mg/kg)reduced ELI(3.36±0.31,2.90±0.46 and 2.8±0.23,respectively)vs the positive control(5.2±0.33)(P=0.004;P=0.002;P=0.001,respectively).There were no significant changes in acidity with D-002 treatment,and only the highest dose reduced the volume of the gastric secretion(1.92±0.25)vs the positive control(2.69±0.09,P=0.013).D-002(25,100 and 200 mg/kg)lowered the esophageal MDA(2.05±0.16,1.98±0.22and 1.93±0.22,respectively)(P=0.01;P=0.03;P=0.03,respectively)and SH group concentration(0.87±0.06,0.79±0.08 and 0.77±0.06,respectively)(P=0.04;P=0.04;P=0.02)vs the positive control(2.56±0.10 and 1.02±0.05,respectively).Omeprazole decreased ELI(2.54±0.47),gastric secretion volume(1.97±0.14)and acidity(158.5±22.79),esophageal MDA(1.87±0.13)and SH group(0.72±0.05)concentrations vs the positive control(P=0.002;P=0.001;P=0.02;P=0.003;P=0.002,respectively).CONCLUSION:Acute oral administration of D-002 decreased macroscopic esophageal lesions and oxidative stress in rats with experimentally induced GER,without modifying gastric secretion acidity.     

α-硫辛酸降低糖尿病大鼠肾脏氧化应激水平

将大鼠分成正常对照（NC）组、糖尿病（DM）组及糖尿病加α-硫辛酸（DM＋ALA）组进行实验。4周后DM组24小时尿白蛋白（UAlb/24h）、肾重/体重（KW/BW）和丙二醛（MDA）含量均较NC组增加，总超氧化物歧化酶（TSOD）活性降低，谷胱甘肽过氧化物酶（GSH-Px）活性升高，过氧化氢酶（CAT）活性无变化；DM＋ALA组较DM组UAlb/24h、KW/BW和MDA水平降低，TSOD、GSH-Px和CAT活性无改变。结果说明，ALA能减低DM大鼠肾皮质氧化应激水平，延缓糖尿病肾病进展。     

Nicorandil improves diabetes and rat islet beta-cell damage induced by streptozotocin in vivo and in vitro

OBJECTIVE: N-(2-hydroxyethyl)-nicotinamide nitrate (nicorandil) is a unique anti-anginal agent, reported to act as both an ATP-sensitive K(+) channel opener (PCO) and a nitric oxide donor. It also has an anti-oxidant action. We examined the effects of nicorandil on streptozotocin (STZ)-induced islet beta-cell damage both in vivo and in vitro. DESIGN AND METHODS: STZ-induced diabetic Brown Norway rats (STZ-DM) were fed with nicorandil-containing chow from day 2 (STZ-DM-N48), 3 (STZ-DM-N72), and 4 (STZ-DM-N96) to day 30. Body weight, blood glucose, and plasma insulin were measured every week. For the in vitro assay, neonatal rat islet-rich cultures were performed and cells were treated with nicorandil from 1 h before to 2 h after exposure to STZ for 30 min. Insulin secretion from islet cells was assayed after an additional 24 h of culture. We also observed the effect of nicorandil on the generation of reactive oxygen species (ROS) from rat inslinoma cells (RINm5F). RESULTS: Body weight loss and blood glucose levels of STZ-DM-N48 rats were significantly lower than those of STZ-DM rats. Immunohistochemical staining of insulin showed preservation of insulin-secreting islet beta-cells in STZ-DM-N48 rats. Nicorandil also dose-dependently recovered the insulin release from neonatal rat islet cells treated with STZ in in vitro experiments. Nicorandil did not act as a PCO on neonatal rat islet beta-cells or RINm5F cells, and did not show an inhibitory effect on poly(ADP-ribose) polymerase-1. However, the drug inhibited the production of ROS stimulated by high glucose (22.0 mmol/l) in RINm5F cells. CONCLUSIONS: These results suggested that nicorandil improves diabetes and rat islet beta-cell damage induced by STZ in vivo and in vitro. It protects islet beta-cells, at least partly, via a radical scavenging effect.