诱导型一氧化氮合酶在GK糖尿病大鼠心肌梗死后的表达

目的本研究通过制作GK糖尿病大鼠及非糖尿病大鼠心肌梗死模型,观察诱导型一氧化氮合酶(iNOS)的表达在糖尿病大鼠合并心肌梗死时与非糖尿病大鼠心肌梗死时的变化,为冠心病合并糖尿病的心脏病理改变提供理论基础与科学依据。方法应用体质量在200～250g的雄性GK糖尿病大鼠及其对照雄性Wistar大鼠通过开胸手术结扎麻醉大鼠冠状动脉左前降支制作大鼠在体心肌梗死模型。心肌梗死模型制作前测量血糖。手术成功后分组饲养大鼠3周。3周后,测量血糖,活体剪取心脏,进行iNOS的免疫组织化学染色及实时聚合酶链反应(RT-PCR)检测。结果①GK糖尿病大鼠血糖明显高于Wistar大鼠血糖(P<0.05);②Wistar心肌梗死组与GK心肌梗死组在缺血区可见到心肌细胞iNOS大量阳性染色,但GK心肌梗死组与Wistar心肌梗死组相比,iNOS阳性染色减少,二者吸光度测定值差异有统计学意义(P<0.05);③Wistar心肌梗死组与GK心肌梗死组iNOSmRNA表达在缺血区明显增加,但GK心肌梗死组iNOSmRNA表达减少,二者之间差异有统计学意义(P<0.05)。结论iNOS在糖尿病大鼠合并心肌梗死时其在缺血区的表达是降低的,表明高血糖可能抑制iNOS的表达,使体内一氧化氮(NO)生成减少,不利于梗死后血供的恢复。     

胃癌中诱导型一氧化氮合酶、IL-8的表达与意义

目的探讨诱导型一氧化氮合酶(inducible NOS,iNOS)和白介素8(IL-8)在胃癌中的表达及意义。方法胃癌组织标本70例(包括癌组织和非癌组织),采用HE染色对胃癌标本进行组织分型,免疫组织化学sABC法检测不同类型胃癌组织和不同位置中的iNOS和IL-8的表达。结果①64．29％(45／70)胃癌组织中表达iNOS蛋白,在高、中分化腺癌中iNOS表达占46．67％(14／30);在低分化腺癌iNOS表达占77．50％(31／40);iNOS的表达与胃癌组织分化程度显著相关;②IL-8在高、中分化与低分化腺癌中的表达率没有差异,在癌组织和非癌组织两组中IL-8的表达率,有显著性差异。结论iNOS和IL-8可能在胃黏膜细胞癌变过程中起重要作用。     

布地奈德对哮喘大鼠中性粒细胞诱导型一氧化氮合酶表达的影响

目的：观察诱导型一氧化氮合酶（iNOS）蛋白在哮喘大鼠血中性粒细胞（PMN）中的表达,探讨PMN参与哮喘炎症的可能机制,并研究布地奈德的影响。方法：采用卵白蛋白（OVA）和Al（OH）3制备大鼠哮喘模型,分离纯化血PMN,免疫细胞化学法检测PMN中iNOS蛋白的表达水平,比色法测定支气管肺泡灌洗液（BALF）中NO浓度。结果：哮喘组大鼠PMN中iNOS蛋白的表达水平显著高于正常对照组（P〈0.01）,布地奈德治疗组PMN中iNOS蛋白的表达水平显著低于哮喘组（P〈0.01）;哮喘组支气管壁iNOS蛋白的表达水平显著高于正常对照组（P〈0.01）,布地奈德治疗组支气管壁iNOS蛋白的表达水平显著低于哮喘组且高于正常对照组（均P〈0.01）;哮喘组BALF中NO浓度显著高于正常对照组（P〈0.01）,布地奈德治疗组BALF中NO浓度显著低于哮喘组（P〈0.01）;PMN中iNOS蛋白的表达水平与BALF中NO浓度呈显著正相关（n=29,r=0.754,P〈0.01）;支气管壁iNOS蛋白的表达水平与BALF中NO浓度呈显著正相关（n=29,r=0.760,P〈0.01）。结论：哮喘大鼠PMN合成iN-OS蛋白的功能增加,PMN可能部分通过iNOS参与哮喘的发病,这种功能可以部分被布地奈德所抑制。     

诱导型一氧化氮合酶在哮喘大鼠肺组织及中性粒细胞中的表达及地塞米松对其的影响

目的：观察诱导型一氧化氮合酶（iNOS）在哮喘大鼠肺组织及血中性粒细胞（PMN）中的表达,探讨PMN参与哮喘炎症的可能作用机制。方法：采用大鼠哮喘模型,随机分成哮喘组、对照组、地塞米松干预组,分离纯化血PMN,免疫组织化学法检测iNOS蛋白的表达水平,测定支气管肺泡灌洗液（BALF）中NO浓度。结果：哮喘组PMNiNOS蛋白光密度（OD）值（0.122±0.017）的表达水平显著高于对照组OD值（0.076±0.014）（P〈0.01）,地塞米松干预组OD值（0.089±0.013）PMNiNOS蛋白的表达水平显著低于哮喘组OD值（P〈0.01）,但与对照组相比差异无统计学意义。哮喘组支气管壁iNOS蛋白OD值（0.243±0.039）的表达水平显著高于对照组（0.119±0.016）（P〈0.01）,地塞米松干预组OD值（0.164±0.016）支气管壁iNOS蛋白的表达水平显著低于哮喘组且高于对照组（P均〈0.01）。哮喘组BALFNO浓度（8.59±1.07）ng/mL显著高于对照组（3.69±1.00）ng/mL（P〈0.01）,地塞米松干预组BALFNO浓度（4.28±0.89）ng/mL显著低于哮喘组（P〈0.01）,但与对照组相比差异无统计学意义。PMNiNOS蛋白的表达水平与BALFNO浓度呈显著正相关（n=29,r=0.770,P〈0.01）。支气管壁iNOS蛋白的表达水平与BALFNO浓度呈显著正相关（n=29,r=0.802,P〈0.01）。结论：哮喘大鼠PMN合成iNOS蛋白的功能增加,PMN可能通过iNOS参与哮喘的发病机制,这种功能可以部分被地塞米松所抑制。     

五味子乙素对染矽尘大鼠肺组织一氧化氮水平和诱导型一氧化氮合酶mRNA表达动态变化的影响

目的观察五味子乙素(Sch-B)对染矽尘大鼠肺组织一氧化氮(NO)水平和诱导型一氧化氮合酶(iNOS)mRNA动态变化的影响。方法将96只大鼠随机分为对照组、染矽尘组、Sch-B组,每组32只,气管暴露法建立大鼠矽肺模型,造模后d 1开始灌胃给予Sch-B治疗,药物治疗3 d、7 d、14 d和28 d后,HE染色检测肺组织病理改变;硝酸还原酶法测肺组织NO含量;RT-PCR检测肺组织iNOS mRNA的表达。结果 HE染色显示Sch-B组大鼠肺损伤较染矽尘组明显减轻。NO含量和iNOS mRNA表达在染尘后各个时间点均较相应的对照组明显升高(P<0.01),其中NO含量在d 7时达到高峰后开始下降,iNOS mRNA的峰值出现在d 14。五味子组与染矽尘组相比,各时间点NO含量均明显降低(P<0.05或P<0.01),而iNOS mRNA表达仅在d 3和d 7时降低明显(P<0.05)。结论染矽尘大鼠肺组织存在着NO含量和iNOS mRNA的动态变化。Sch-B能减轻染矽尘大鼠肺组织的纤维化程度,其机制可能与染尘初期Sch-B降低iNOS mRNA转录水平,抑制NO炎症介质的合成与释放有关。     

结肠癌组织中诱导型一氧化氮合酶、p53、nm23表达及其相关关系

目的 探讨结肠癌组织中诱导型一氧化氯合酶(iNOS)表达与Dukes分期之间的相关关系，iNOS表达与p53、nm23之间有无相关性。方法 应用免疫组织化学检测49例结肠癌、30例癌旁组织及30例正常结肠粘膜中iNOS蛋白表达，同时检测49例结肠癌中p53、nm23蛋白表达。应用原位分子杂交方法检测49例结肠癌中iNOS mRNA表达。结果 49例结肠癌组织中iNOS表达阳性率为75．5％(37／49)，30例癌旁组织中iNOS阳性表达率为20％(6／30)，30例正常结肠粘膜组织中iNOS呈阴性表达。结肠癌组织中iNOS表达明显高于癌旁组织，统计学分析有显性差异(P＜0．01)。DukesA、B期iNOS蛋白及iNOSmRNA的表达明显高于DukesC、D期，有显性差异(P＜0．01)。iNOS表达与p53表达呈正相关性(r＝0．7432，P＜0．001)，iNOS表达与nm23表达呈负相关性(r＝-0．6597，P＜0．001)。结论 (1)iNOS在结肠癌组织中表达明显上调，提示iNOS表达可能在结肠癌的发生发展过程中起重要的作用。(2)结肠癌组织中iNOS表达与p53基因的突变有关，两可能在结肠癌的形成过程中起互相促进作用。(3)结肠癌组织中iNOS表达伴有nm23基因表达的缺失，表明iNOS表达可能在结肠癌转移中有促进作用。     

金钗石斛对糖尿病大鼠肾组织中糖基化终产物表达的干预作用

目的研究金钗石斛对糖尿病(DM)大鼠肾组织中肾脏糖基化终产物受体(RAGE)表达的干预作用。方法将W istar大鼠随机分3组,用链脲佐菌素(STZ)建立DM模型,金钗石斛水煎剂10 g/(kg.d)灌胃给药12周后,肾组织病理切片HE染色观察肾组织病理变化;生化法测定血糖、尿蛋白、肌酐浓度;荧光光谱法测定尿液和血清糖基化终产物(AGE)含量;免疫组化检测肾组织RAGE蛋白;实时荧光定量PCR检测肾组织RAGE mRNA表达。结果金钗石斛可降低DM模型大鼠血糖,减轻肾脏损害,降低血清中AGE以及肾组织RAGE mRNA和蛋白表达水平。结论金钗石斛干预减轻DM肾脏功能损害可能通过降低血清中AGE和下调肾组织中RAGE表达而实现。     

贫铀对大鼠肺诱导型一氧化氮合酶基因表达的影响

目的通过研究贫铀(depleted uranium,DU)颗粒气管灌注大鼠肺中的诱导型一氧化氮合酶(iNOS)基因表达的变化,揭示DU对肺组织的毒性作用机制。方法Wistar大鼠20只随机分为4组,1个对照组,3个染铀组,剂量分别为1、3、5 mg/ml气管灌注不同剂量DU颗粒3个月后,将大鼠肺组织iNOS mRNA进行RT-PCR并通过凝胶成像分析系统扫描RT-PCR产物,用内参半定量法分析iNOS mRNA的变化。结果对照组无iNOS mRNA表达,各染铀组扩增产物电泳条带吸光度值(A)明显高于对照组(P<0.05);其中13、mg组产物电泳条带A值逐渐增高,3 mg组到达高峰,5 mg组产物电泳条带A值明显低于13、mg组(P<0.05)。结论DU颗粒气管灌注能使大鼠肺组织iNOS mRNA表达水平升高,并与DU剂量呈正相关。DU剂量增高到一定程度则使iNOS mRNA表达水平降低,这种变化可能与DU化学毒性和辐射损伤的复合作用有关。     

糖肾康对糖尿病大鼠肾脏诱导型一氧化氮合酶基因表达的影响

目的:探讨中药复方糖肾康对糖尿病大鼠肾脏诱导型一氧化氮合酶(iNOS)基因表达的影响。方法:采用链脲佐菌素(STZ)腹腔注射建立模型,随机分为正常对照组、模型组、中药治疗组、中药对照组、西药对照组,并应用反转录多聚酶链反应技术(RT-PCR),观察iNOSmRNA在各组间的表达情况。结果:与正常对照组相比,模型组肾脏iNOS表达明显增高,中药及西药均可使iNOS表达水平下调,中药治疗组下调更为明显。结论:糖肾康能明显降低糖尿病大鼠升高的血糖,并纠正了升高的iNOSmRNA的表达,推测抑制NO的合成可能是其机制之一。     

FK506抑制脊髓挫伤后诱导型一氧化氮合酶表达的实验研究

目的观察大鼠脊髓挫伤后早期应用FK506对诱导型一氧化氮合酶(iNOS)表达的抑制作用。方法45只成年雄性大鼠随机分为假手术组、对照组和治疗组。治疗组在脊髓挫伤后5 min一次性经尾静脉注射FK506(0.3mg/kg),其余两组以相同方法给予0.9%生理盐水。伤后3,7,14,21 d采用BBB评分法进行后肢运动功能评价,应用逆转录聚合酶链反应(RT-PCR)和免疫组织化学染色检测iNOS的mRNA和蛋白质的表达,同时行脊髓组织尼氏染色病理学观察。结果治疗组病理学观察和行为学评分明显优于对照组(P<0.05,P<0.01);iNOS的mRNA和蛋白质的表达均于伤后7 d达高峰,两者表达在治疗组明显低于对照组(P<0.05,P<0.01)。结论FK506能抑制大鼠脊髓挫伤后iNOS表达,减轻继发性损害,从而改善脊髓损伤后的功能恢复。     

冠心病合并2型糖尿病患者糖基化终产物与单核细胞TLR4的关系

目的：探讨分析冠心病(CHD)合并糖尿病(DM)患者糖基化终产物(AGEs)与单核细胞toll样受体4(TLR4)的关系。方法CHD+DM患者58例(CHD+DM组), CHD患者60例(CHD组),健康对照组50例。采用酶联免疫吸附测定(ELISA)法检测各组的AGEs,用流式细胞仪检测外周血单核细胞TLR4mRNA相对表达量及TLR4阳性单核细胞比率。结果与健康对照组比较, CHD+DM组及CHD组AGEs及外周血单核细胞TLR4mRNA相对表达量、TLR4阳性单核细胞比率明显增高(P<0.05);CHD+DM组与CHD组比较, CHD+DM组AGEs及外周血单核细胞TLR4mRNA相对表达量、TLR4阳性单核细胞比率增高(P<0.05);相关性分析显示升高的AGEs与升高的TLR4mRNA相对表达量及TLR4阳性单核细胞比率呈正相关。结论 CHD+DM患者AGEs及TLR4表达高于CHD患者;CHD患者AGEs及TLR4表达高于健康对照组。AGEs与TLR4的表达呈正相关。     

2型糖尿病大鼠超声心动图的变化

目的 探讨2型糖尿病(Type 2 diabetes mellitus,T2DM)大鼠超声心动图的变化及胰岛素对其的影响.方法 高糖高脂饮食加小剂量链脲佐菌素腹腔注射(STZ,30 mg/kg)制备T2DM大鼠模型,随机临床对照试验(randomized controlled trials RCT)分为正常对照组、糖尿病(Diabetes mellitus,DM)组和胰岛素治疗组(每只3 U/d股内侧皮下注射),对照组和DM组注射等剂量的生理盐水(股内侧皮下注射),每天1次,持续喂养2个月.结果 与对照组组比较,糖尿病模型组大鼠LVEDV、LVESV和SV均明显降低;其他有所增加(P＜0.05),胰岛素能显著降低LVFS、EF,对其他超声心动图指标无明显影响.结论 胰岛素能降低2型糖尿病大鼠的血糖,改善心功能,可不同程度下调SAN间质胶原的沉积.     

糖尿病性阴茎勃起功能障碍大鼠阴茎海绵体Cx43的表达

目的观察糖尿病(DM)性勃起功能障碍(ED)大鼠阴茎海绵体缝隙连接蛋白Cx43的表达。方法Wistar大鼠135只,随机分为Ⅰ、Ⅱ、Ⅲ三组,每组分为DM组25只,非糖尿病组(NDM)20只。DM组腹腔注射链尿菌素(50mg/kg体重)建立DM动物模型后,注射阿朴吗啡观察8、12及16周大鼠阴茎勃起情况,筛选DM性ED大鼠模型,测定其阴茎海绵体组织Cx43表达情况。结果DM性ED大鼠阴茎海绵体平滑肌组织Cx43表达与对照组相比显著降低(P<0·05),随DM病程延长,Cx43表达明显下降(P<0·01)。结论DM严重影响阴茎勃起功能,海绵体平滑肌组织Cx43表达降低可能是其发病机制之一。     

The effect of resveratrol on glycation and oxidation products in plasma and liver of chronic methylglyoxal-treated rats

Background

Methylglyoxal (MG) is a highly reactive dicarbonyl compound. It is produced by processes like glycolysis, glucose autooxidation, lipid peroxidation, and protein glycation. It is a major precursor of advanced glycation end products (AGE). It also exacerbates oxidative stress in the organism. Although there are some in vitro studies investigating the effect of resveratrol (RES) as an antioxidant and antiglycating agent on MG-induced toxicity, in vivo effect of RES is unknown. Therefore, we aimed to investigate the efficiency of RES in chronic MG-treated rats.

前列地尔对局灶性脑缺血模型大鼠大脑皮层中iNOS和eNOS表达的影响

目的:探讨前列地尔对局灶性脑缺血模型大鼠大脑皮层中诱导型一氧化氮合酶(iNOS)和内皮型一氧化氮合酶(eNOS)表达的影响。方法:取大鼠随机分为假手术组、模型组、阳性对照(尼莫地平1mg.kg-1)组和前列地尔低、中、高剂量(1.25、2.50、5.00μg.kg-1)组,每组10只,腹腔注射相应药物6d,每日1次,末次给药后建立局灶性脑缺血模型,大鼠清醒后进行神经功能缺损评分,采用免疫组化法和免疫印迹法检测各组大鼠建模2h后iNOS、eNOS的表达。结果:与假手术组比较,其余各组神经功能缺损评分均明显增加,iNOS阳性细胞数和表达量均明显增加,除模型组外其余各组eNOS阳性表达量均增加(P均<0.05);与模型组比较,阳性对照组和前列地尔中、高剂量组神经功能缺损评分均明显降低,阳性对照组和前列地尔3个剂量组iNOS阳性细胞数和表达量均明显降低、eNOS阳性细胞数和表达量均明显增加(P均<0.05)。结论:前列地尔预处理对局灶性脑缺血模型大鼠具有保护作用,其机制可能与下调大脑皮层iNOS、上调eNOS的表达有关。     

Deficiency of iNOS Does Not Prevent Isoproterenol-induced Cardiac Hypertrophy in Mice

We investigated whether deficiency of inducible nitric oxide synthase (iNOS) could prevent isoproterenol-induced cardiac hypertrophy in iNOS knockout (KO) mice. Isoproterenol was continuously infused subcutaneously (15 mg/kg/day) using an osmotic minipump. Isoproterenol reduced body weight and fat mass in both iNOS KO and wild-type mice compared with saline-infused wild-type mice. Isoproterenol increased the heart weight in both iNOS KO and wild-type mice but there was no difference between iNOS KO and wild-type mice. Posterior wall thickness of left ventricle showed the same tendency with heart weight. Protein level of iNOS in the left ventricle was increased in isoproterenol-infused wild-type mice. The gene expression of interleukin-6 (IL-6) and transforming growth factor-β (TGF-β) in isoproterenol-infused wild-type was measured at 2, 4, 24, and 48-hour and isoproterenol increased both IL-6 (2, 4, 24, and 48-hour) and TGF-β (4 and 24-hour). Isoproterenol infusion for 7 days increased the mRNA level of IL-6 and TGF-β in iNOS KO mice, whereas the gene expression in wild-type mice was not increased. Phosphorylated form of extracellular signal-regulated kinases (pERK) was also increased by isoproterenol at 2 and 4-hour but was not increased at 7 days after infusion in wild-type mice. However, the increased pERK level in iNOS KO mice was maintained even at 7 days after isoproterenol infusion. These results suggest that deficiency of iNOS does not prevent isoproterenol-induced cardiac hypertrophy and may have potentially harmful effects on cardiac hypertrophy.     

Long-term methylglyoxal intake aggravates murine Th2-mediated airway eosinophil infiltration

Asthma outcomes is aggravated in obese patients. Excess of methylglyoxal (MGO) in obese/diabetic patients has been associated with diverse detrimental effects on cell function. This study aimed to evaluate the effects of long-term oral intake of MGO on ovalbumin-induced eosinophil inflammation. Male C57/Bl6 mice received 0.5% MGO in the drinking water for 12 weeks. Mice were sensitized and challenged with ovalbumin (OVA), and at 48 h thereafter, bronchoalveolar lavage (BAL) fluid and lungs were collected for cell counting, morphological analysis, and ELISA, mRNA expressions and DHE assays. In MGO-treated mice, OVA challenge significantly increased the peribronchiolar infiltrations of inflammatory cells and eosinophils compared with control group. Higher levels of IL-4, IL-5, and eotaxin in BAL fluid were also detected in MGO compared with control group. In addition, lung tissue of MGO-treated mice displayed significant increases in mRNA expressions of NF-κB and iNOS whereas COX-2 expression remained unchanged. The high TNF-α mRNA expression observed in lungs of OVA-challenged control mice was not further increased by MGO treatment. In MGO group, OVA-challenge increased significantly the NOX-2 and NOX-4 mRNA expressions, without affecting the NOX-1 expression. Levels of reactive-oxygen species (ROS) were significantly higher in lungs of MGO-treated mice, and no further increase by OVA-challenge was observed. In conclusion, 12-week intake of MGO exacerbates Th2-mediated airway eosinophil infiltration by activation of NF-kB/iNOS-dependent signaling pathway and positive regulation of NOX-2 and NOX-4 in the lung tissues. Scavengers of MGO could be an option to prevent obesity-related asthma.     

Therapeutic administration of 3,4,5-trimethoxy-4'-fluorochalcone,a selective inhibitor of iNOS expression,attenuates the development of adjuvant-induced arthritis in rats

We have previously investigated the effects of a series of dimethoxy- and trimethoxychalcone derivatives, with various patterns of fluorination, on nitric oxide production in LPS-stimulated murine RAW 264.7. The present study was designed to determine if 3,4,5-trimethoxy-4'-fluorochalcone (CH 17) could modulate the production of NO and/or prostaglandins in vivo. On the mouse macrophage cell line RAW 264.7 CH 17 inhibited dose-dependently NO production, with an IC₅₀ value in the nanomolar range, and reduced PGE₂ levels by a 58% at 10 M. This compound had no direct inhibitory effect on iNOS and COX-2 activities. NO reduction was the consequence of inhibition of the expression of iNOS. In vitro experiments indicated that CH 17 is an inhibitor of the nuclear factor-B (NF-B) pathway of cellular activation in macrophages. This compound exhibited in vivo an inhibitory behaviour correlated with its in vitro results on nitrite and PGE₂ accumulation. In the rat adjuvant-induced arthritis, oral administration of CH 17 (25 mg/kg) on days 17–24 after adjuvant injection, significantly inhibited paw oedema, protected from weight loss and reduced the levels of inflammatory mediators (nitrites and PGE₂) in paw homogenates, without affecting PGE₂ levels in stomach homogenates. The profile and potency of this compound, a selective inhibitor of iNOS expression that interferes with NF-B activation, may have relevance for the inhibition of the inflammatory response, representing a new approach to the modulation of different inflammatory pathologies.     

还原型谷胱甘肽对糖尿病大鼠视网膜病变干预研究

目的探讨糖尿病视网膜病变与诱导型一氧化氮合酶的表达的关系并探讨还原型谷胱甘肽对诱导型一氧化氮合酶表达的影响以及对糖尿病视网膜病变的防治作用。方法雄性SD大鼠70只随机分成对照组10只,糖尿病1、3、6月组以及还原型谷胱甘肽干预3、6月组各12只。分别留取视网膜标本,部分标本观测视网膜病理改变;部分标本采用免疫组化法测定诱导型一氧化氮合酶表达。结果视网膜病理结果显示：与正常对照组相比,糖尿病1、3、6月组视网膜病理改变逐步加重;免疫组化分析结果显示诱导型一氧化氮合酶表达在糖尿病各组均明显增强（P均〈0.05）,干预组较糖尿病各组均有明显改善（P均〈0.05）。结论糖尿病视网膜病变早期就出现视网膜诱导型一氧化氮合酶表达增强,且随着视网膜组织病理学改变而持续活化。还原型谷胱甘肽有效抑制了诱导型一氧化氮合酶表达,从而达到视网膜保护的目的 。