Nitric oxide synthases modulate progenitor and resident endothelial cell behavior in galactosemia

We used knockout animals of either inducible nitric oxide synthase (iNOS(/)) or endothelial NOS (eNOS(/)) to characterize the role of NOS in galactosemia, a model of diabetic retinopathy. NADH oxidase and nitrotyrosine were used as biomarkers of oxidative stress and vascular dysfunction. These animals were engrafted with hematopoietic stem cells (HSC) expressing green fluorescence protein (gfp(+)) to characterize the contribution of HSC and endothelial progenitor cells to neovascularization. Increased NADH oxidase activity and superoxide generation occurred in all galactose-fed mice. eNOS(/) mice demonstrated increased iNOS immunoreactivity in their retinal vasculature. Nitrotyrosine levels were low at baseline in the wild-type (WT) mice, eNOS(/) and iNOS(/) mice, and the galactose-fed iNOS mice and increased following galactose feeding in eNOS(/) and WT. Galactose-fed WT.gfp and iNOS(/).gfp chimeric animals had areas of perfused new vessels composed of gfp(+) cells. In contrast, galactose-fed eNOS(/).gfp mice produced copious, unbranched, nonperfused tubes. Thus, nitric oxide modulates HSC behavior and vascular phenotype in the retina. Although there is increased NADH oxidase and superoxide in galactosemic mice of all isoforms, iNOS is the source of nitric oxide responsible for peroxynitrite and nitrotyrosine formation that leads to the pathology observed in galactosemic mice.     

骨髓间充质干细胞移植对缺血心肌的血管新生及增殖-凋亡影响

 目的 探讨骨髓间充质干细胞（BMSC）移植对缺血心肌的血管新生及增殖-凋亡的影响。方法 将雄性小鼠BMSC经尾静脉输入异丙肾上腺素性心肌缺血雌性小鼠（BMSC组）。另设正常对照组和未治疗组。5周后处死小鼠,荧光定量PCR检测心肌Y染色体鉴别基因(SRY)、血管内皮生长因子（VEGF）的表达。天狼猩红染色分析心肌胶原含量。免疫组织化学染色观察心肌VEGF、核增殖抗原(PCNA)和细胞凋亡蛋白酶（caspase-3）的分布。 结果 BMSC组心肌SRY表达明显升高（11.22±0.90 vs 1.05±0.47, P<0.05）。与未治疗组相比,BMSC组的心肌胶原沉积减少(3.44±0.84 vs 8.44±1.09, P<0.05),VEGF(14.19±0.37 vs 11.88±0.28, P<0.05)和PCNA(4.08±0.18 vs 0.64±0.05, P<0.05)表达上调,caspase-3降低（0.46±0.11 vs 3.12±0.28, P<0.05）。 结论 BMSC能归巢至缺血心肌并促进微血管新生,改善心肌增殖-凋亡状态。     

体外反搏对心肌梗死犬一氧化氮系统的影响

目的:探讨体外反搏对心肌梗死犬一氧化氮(NO)、一氧化氮合酶(NOS)和其基因表达的影响。方法:19只健康杂种犬随机分为对照组、缺血组和缺血+反搏组(反搏组)3组,采用开胸结扎冠状动脉左前降支的方法建立心肌缺血模型,用改良硝酸还原酶法测定心肌缺血前后血清NO含量、以及心肌组织的NO含量和NOS比活性,采用免疫组化方法检测缺血区心肌组织的NOS亚型即诱导型NOS(iNOS)和内皮型NOS(eNOS)的蛋白合成,用原位杂交方法检测构成型NOS(cNOS)信使核糖核酸(mRNA)的基因表达。结果:在冠状动脉结扎前和结扎后60min,3组犬血清NO含量均无明显差异(P＞0.05);结扎后120min和180min时,反搏组犬血清NO含量明显高于缺血组(P＜0.05)。正常组和反搏组犬心肌组织NO含量和NOS比活性均大于缺血组(P＜0.05)。免疫组化结果表明心肌缺血时iNOS蛋白合成增多,而eNOS蛋白合成减少;体外反搏对iNOS有抑制作用,对eNOS有促进作用。此外心肌缺血时cNOSmRNA的表达明显减少,反搏可促进cNOSmRNA的表达。结论:体外反搏促进NO的产生可能是其抗心肌缺血性损伤的重要机制之一。     

高原低氧对大鼠下丘脑谷氨酸、天门冬氨酸和NOS的影响

目的:观察高原低氧大鼠下丘脑谷氨酸(Glu)、天门冬氨酸(Asp)和一氧化氮合酶(NOS)的变化。方法:应用氨基酸测定和NADPH-d组化法,检测高原低氧模型大鼠下丘脑Glu、Asp含量和NADPH-d阳性神经元的数量。结果:高原低氧大鼠下丘脑Glu、Asp含量明显增多,室旁核、视上核可见密集深染的NADPH-d阳性神经元;用NMDA受体拮抗剂氯氨酮(Ketamine)和AP-V对高原低氧大鼠进行预处理后置于低压氧舱,观察到大鼠下丘脑室旁核、视上核NADPH-d阳性神经元数明显少于相应时间的高原低氧组(P＜0.01)。结论:NMDA受体可能参与了高原低氧引起的下丘脑NOS的表达。     

Association of the eNOS E298D polymorphism and the risk of myocardial infarction in the Greek population

Background  

Nitric oxide (NO), produced by endothelial nitric oxide synthase (eNOS), plays a key role in the regulation of vascular tone. Endothelium-derived NO exerts vasoprotective effects by suppressing platelet aggregation, leukocyte adhesion and smooth muscle cell proliferation. The E298D polymorphic variant of eNOS has been associated with myocardial infarction (MI), but data relating to this variant are divergent in Greece. Accordingly, we examined a possible association between the E298D polymorphism of the eNOS gene and MI in a subgroup of the Greek population.     

Inducible and endothelial nitric oxide synthase expression during development of transplant arteriosclerosis in rat aortic grafts.

In the vascular system, distinct isoforms of nitric oxide synthase (NOS) generate nitric oxide (NO), which acts as a biological messenger. Its role in the development of transplant arteriosclerosis (TA) is still unclear. To investigate whether NO is involved in TA, we studied the expression of NOS isoforms, inducible NOS (iNOS) and endothelial NOS (eNOS), by immunohistochemistry and in situ hybridization during the first two post-transplantation months and their relation with cold ischemia (1 to 24 hours) and reperfusion injury using an aortic transplantation model in the rat. We found an increased iNOS expression in the intima and adventitia and a decreased expression in the media, whereas eNOS expression was not significantly altered during the development of TA. Co-localization studies suggested that iNOS-positive cells were vascular smooth muscle cells, monocyte-derived macrophages, and endothelial cells. Prolonged ischemic storage time resulted in an increase in eNOS expression in the neointima. In situ hybridization showed iNOS mRNA expression by vascular cells in the neointima and media. NO produced by iNOS and eNOS may be involved, at least in part, in the pathogenesis of TA in aortic grafts. Additional studies are needed to confirm the modulatory mechanism of NO during the development of TA.     

内皮型一氧化氮合酶基因G894T突变与中国人冠状动脉粥样硬化性心脏病的相关研究

目的 探讨内皮型一氧化氮合酶（endothelial nitric oxide synthase,e NOS）基因第7外显子G894T点突变与中国人冠状动脉粥样硬化性心脏病（简称冠心病）发病之间的关系。方法 应用聚合酶链反应技术，限制性内切酶分析和病例－对照方法，检测了108名中国汉族正常人，106例冠心病患者的eNOS基因G894T点突变频率。比较各组间的基因型频率与等位基因频率。结果 （1）中国汉族正常人eNOS基因G894T突变GG，GT，TT基因型频率分布为0.9095,0.0883和0.0021;G,T等位基因频率分别为0．9537和0．0463。（2）冠心病及其心肌梗塞亚组eNOS基因GT＋TT型频率分别为0．2219和0．2387，与GG型相比，均显著高于正常人（P＜0．05；冠心病组及心肌梗塞亚组T等位基因频率分别为0．1179和0．1275，均极显著高于正常人（P＜0．01。（3）冠状动脉造影确诊的冠心病患者eNOS基因G894T突变频率在单支，双支和多支病变组之间差异均无显著性（P＞0．05）。结论 eNOS基因G894T突变可能是中国人冠心病遗传易感性的基因标志之一。     

甘氨酸对心肌缺血-再灌注小鼠一氧化氮系统和Bcl-2 mRNA表达的影响

目的:探讨甘氨酸(Gly)对心肌缺血-再灌注(MI/R)损伤的防治作用及机制,为临床缺血性心脏病的防治提供新的思路与方法。方法: 将小鼠随机分为5组,以Gly等药物定量灌胃处理。1周后,腹腔注射垂体后叶素和硝酸甘油复制MI/R模型,同时记录不同时点的肢体Ⅱ导联心电图。4 h后,分别用比色法和硝酸还原酶法检测小鼠心肌组织中一氧化氮合酶(NOS)、诱导型一氧化氮合酶的活性(iNOS)和一氧化氮(NO)的含量;用逆转录-多聚酶链式反应(RT-PCR)测定各组小鼠心肌组织Bcl-2 mRNA的表达。结果: MI/R组小鼠心电图J点发生明显偏移。 Gly预处理组小鼠心肌组织总NOS活性、NO含量及Bcl-2 mRNA的表达显著升高,而iNOS的活性显著下降。结论: Gly能保护心脏,减轻MI/R引发的损伤。Gly的这一作用可能与其增加缺血再灌注心肌组织中NOS的活性及NO的生成,抑制iNOS的活性,以及促进Bcl-2 mRNA的表达有关。     

从氧自由基、一氧化氮探讨四逆汤抗急性失血性休克的肝脏机制

目的:从氧自由基、一氧化氮探讨四逆汤抗急性失血性休克的肝脏机制。方法:复制急性失血性休克大鼠模型, 分为假手术对照组;单纯休克模型组;休克+生理盐水复苏组;休克+四逆注射液复苏组。四逆注射液(浓度1000g生药/L), 剂量0.1mL/200g大鼠。用生理盐水或四逆注射液治疗3h后处死动物并取组织。测定各组肝脏超氧化物歧化酶(SOD)活性、丙二醛(MDA)水平, 一氧化氮(NO)水平。采用免疫组化染色法, 观察诱导型一氧化氮合酶(iNOS)在肝细胞中的变化特点。RT-PCR观测肝细胞iNOS和内皮源性一氧化氮合酶(eNOS)基因表达的变化。结果:模型组在休克1h后SOD活性明显低于对照组(P＜0.01)、MDA水平明显高于对照组(P＜0.01)。四逆汤组复苏3h后肝组织SOD明显高于生理盐水组(P＜0.01)、MDA低于生理盐水组(P＜0.01)、NO水平明显高于生理盐水组(P＜0.01)。生理盐水组iNOS在肝细胞中染色阳性单位明显高于四逆汤组(P＜0.05)。生理盐水组促进iNOSmRNA的表达。四逆汤组eNOSmRNA的表达增强。结论:四逆汤通过清除氧自由基, 升高NO, 改善肝组织微循环, 减少诱导型iNOS表达的各种因素, 理论上减轻了NO与氧自由基生成的ONOO的细胞毒作用和血管的低反应性, 并对肝脏起到保护作用。     

兔股动脉结扎诱导动脉生成过程中iNOS和eNOS的表达

目的:研究兔后肢动脉生成过程中诱导型一氧化氮合酶(iNOS)和内皮型一氧化氮合酶(eNOS)表达特征.方法:将兔一侧股动脉结扎,另一侧设为对照组.1周后动物被处死.应用免疫荧光组织化学技术检测侧支血管中iNOS及eNOS的表达.用Leica激光共聚焦显微镜观察并拍照.图片用silicongraphicsoctane进行处理.结果:在正常小动脉血管中iNOS的表达很低,在生长的侧支血管iNOS的表达显著上调,是正常小动脉血管的2.8倍.其表达在血管壁的各层可见.正常小动脉血管eNOS的表达呈现一定基础水平,在生长的侧支血管中eNOS的表达呈强阳性,集中在内皮细胞,是正常小动脉血管的2.2倍.结论:侧支血管发育过程中iNOS的表达上调,上调的iNOS和eNOS可能通过生成NO,调节内皮细胞的增殖、移动及炎症的形成,从而对侧支血管的生长发挥重要作用.     

Cardiac repair achieved by bone marrow mesenchymal stem cells/silk fibroin/hyaluronic acid patches in a rat of myocardial infarction model

Bone marrow mesenchymal stem cells/silk fibroin/hyaluronic acid (BMSC/SH) patches were implanted into myocardial infarction (MI) rat hearts to investigate the efficacies of them on enhancing left ventricular (LV) remodeling and cardiac repair. 45 rats were divided into four groups: Sham, MI (MI hearts, induced by a cryo-injury technique), SH and BMSC/SH (MI hearts with implantations of SH and BMSC/SH patches, respectively). After eight weeks of post-implantation, the patches for the SH and BMSC/SH groups were intact and well adhered on the MI zones with no and minor immunological responses, respectively, examined by a CD68 marker, while severe inflammation on the zones was observed for the MI group. The SH group showed the efficacy of cardiac repair on MI zones. Moreover, BMSC/SH group significantly improved the wall thickness of LV, assessed by echocardiography, and had high viability of delivery BMSC, largely reduced apoptosis, significantly promoted neo-vascularization and stimulated the secretions of various paracrine factors such as VEGF, examined by real-time PCR, in MI zones compared with those of the SH and MI groups. In conclusion, the therapeutic efficacies of using BMSC/SH patches for repairing MI hearts were demonstrated by showing the advantages of both bioactive SH patches and BMSC-based therapy.     

Determination of nitric oxide synthase activity and apoptosis of germ cells in different obstruction models

We aimed to determine the changes of inducible nitric oxide synthase (iNOS) and endothelial nitric oxide synthase (eNOS) immunoreactivity and apoptosis after proximal and distal obstruction models on ipsilateral and contralateral testicular tissues. Male albino Wistar rats were randomly divided into three groups (n=30): a control group which underwent sham operations (n=10), a unilateral vasal ligation (n=10) and a unilateral epididymal ligation group (n=10). iNOS and eNOS distribution and apoptosis were studied in both ipsilateral and contralateral testes using quantitative immunohistochemistry. Nitric oxide synthase activity was significantly affected in ipsilateral and contralateral testes cells after vasal and epididymal ligation. eNOS immunoreactivity increased markedly after ipsilateral vasal ligation (ILVL). Degeneration-related changes were also associated with changes in apoptotic rate. Analysis using the terminal dUTP nick end-labeling TUNEL method revealed that apoptotic cell numbers significantly increased after ILVL. p53 and bcl-2 immunoreactivity increased in both experimental groups compared with the sham-operated group. Changes in iNOS and eNOS immunolocalisation were strongly associated with cell damage, because germ cell degeneration was more prominent in the ILVL group. Altered p53 immunolocalisation was also associated with cell degeneration, and a rise in bcl-2 immunoreactivity might be considered to reflect a protective mechanism in the testis. These cellular changes could enlighten understanding of the interaction between testicular functioning and damage.     

Regulation of iNOS-Derived ROS Generation by HSP90 and Cav-1 in Porcine Reproductive and Respiratory Syndrome Virus-Infected Swine Lung Injury

In the lungs, endothelial nitric oxide synthase (eNOS) is usually expressed in endothelial cells and inducible nitric oxide synthase (iNOS) is mainly expressed in alveolar macrophages and epithelial cells. Both eNOS and iNOS are involved in lung inflammation. While they play several roles in lung inflammation formation and resolution, their expression and activity are also regulated by inflammatory factors. Their expression relationship in virus infection-induced lung injury is not well addressed. In this report, we analyzed expression of both eNOS and iNOS, the production of nitric oxide (NO) and reactive oxygen species (ROS), and expression of their associated regulatory proteins, heat shock protein 90 (HSP90) and caveolin-1 (Cav-1), in a swine lung injury model induced by porcine reproductive and respiratory syndrome virus (PRRSV) infection. The combination of upregulation of iNOS and downregulation of eNOS was observed in both natural and experimental PRRSV-infected lungs, while the combination is much enhanced in natural infected lungs. While NO production is much reduced in both infections, ROS was enhanced only in natural infected lungs. Moreover, HSP90 is increased in both natural and experimental infection and less Cav-1 expressed was observed only in the natural PRRSV-infected lungs. Therefore, the increased ROS generation is likely due to the increased iNOS and its unbalanced regulation by HSP90 and Cav-1, and it also likely causes higher endothelial dysfunction in clinical PRRSV-infected lungs.     

血管内皮生长因子基因转染骨髓间充质干细胞同种异体移植治疗大鼠急性心肌梗死

目的探讨同种异体血管内皮生长因子(VEGF)基因转染的骨髓间充质干细胞(MSCs)在大鼠梗死心脏局部存活、分化及对心功能的影响;明确同种异体干细胞及VEGF基因转染干细胞移植治疗急性心肌梗死(AMI)的可行性及效果。方法雄性SD大鼠30只,随机分为单纯注射培养基对照组、MSCs治疗组及VEGF基因转染MSCs治疗组。分离纯化雄性Wistar大鼠骨髓间充质干细胞(rMSCs),于左冠状动脉前降支结扎1h后植入到SD大鼠心组织,移植4周后检测心功能并取心脏行组织染色检查。结果异体大鼠MSCs可在梗死心组织定居、生存;免疫组化检测MSCs转化为心肌细胞及血管内皮细胞;与对照组比较VEGF基因转染异体细胞移植组左室射血分数升高(P<0.05),梗死边缘区心肌面毛细血管数目明显增加(P<0.05)。结论同种异体VEGF基因转染MSCs移植治疗AMI可行、有效。     

CD4+与T淋巴细胞干扰素γ/诱导型一氧化氮合酶/一氧化氮通路在脐带间充质干细胞移植治疗重症肌无力中的作用

背景：有研究表明,CD4+、干扰素γ/诱导型一氧化氮合酶/一氧化氮通路与重症肌无力的发生密切相关。 目的：探讨CD4+ T细胞与干扰素γ/诱导型一氧化氮合酶/一氧化氮通路在脐带间充质干细胞移植治疗重症肌无力中的作用机制。 方法：建立重症肌无力大鼠模型,并进行脐带间充质干细胞经静脉移植治疗,同时设立对照组。流式细胞术检测移植后大鼠腋窝淋巴结细胞CD4+的表达,ELISA法检测其干扰素γ的表达,Griess试剂和比色法检测一氧化氮和一氧化氮合酶水平。 结果与结论：移植1周后,移植组大鼠腋窝淋巴结的淋巴细胞CD4+的表达显著高于模型组(P < 0.01),干扰素γ、一氧化氮及诱导型一氧化氮合酶水平显著低于模型组(P < 0.01)。证实,脐带间充质干细胞移植可上调重症肌无力模型大鼠淋巴细胞CD4+的表达,并调节干扰素γ/诱导型一氧化氮合酶/一氧化氮通路,下调一氧化氮水平,以减轻机体的免疫损伤。     

半枝莲黄酮对Aβ 25-35引起的大鼠皮层星形胶质细胞NOS、HSP70及apoE异常表达的影响

 目的:探讨半枝莲黄酮对Aβ 25-35引起大鼠皮层星形胶质细胞一氧化氮合酶（NOS）热休克蛋白70（HSP70）及载脂蛋白E（apoE）蛋白表达异常变化的影响。方法:培养第3代的大鼠星形胶质细胞随机分为空白对照组、模型组和3个剂量药物组,药物组细胞分别加入17.5、35和70 mg/L半枝莲黄酮作用24 h后,模型组和3个剂量药物组均加入Aβ 25-35 100 μmol/L作用24 h,免疫组化法测定星形胶质细胞中内皮型一氧化氮合酶 (eNOS)、诱导型一氧化氮合酶 (iNOS) 和神经元型一氧化氮合酶 (nNOS)蛋白的表达;Western blotting检测星形胶质细胞中HSP70蛋白的表达; RT-PCR测定细胞中apoE mRNA的表达。结果:与空白组相比,模型组eNOS蛋白含量降低60.83%（P<0.01）,iNOS蛋白含量增加215.03%（P<0.01）,HSP70蛋白含量增加166.67%（P<001）,apoE mRNA含量增加150.00% (P<0.01);半枝莲黄酮17.5、35及70 mg/L能不同程度地提高eNOS蛋白含量73.66%～137.77% (P<0.05),降低iNOS蛋白含量19.40%～44.50%（P<0.01）,降低HSP70蛋白含量1852%～49.38%（P<0.01）,降低apoE mRNA的含量14.17%～41.67% (P<0.01)。结论:半枝莲黄酮对Aβ 25-35引起的大鼠皮层星形胶质细胞的损伤具有抑制作用。半枝莲黄酮可能通过影响星形胶质细胞发挥对阿尔茨海默病的治疗作用。     

间歇性低氧预处理对缺血心肌的促血管生成作用的实验研究

目的:采用冠状动脉左前降支部分结扎的方法复制慢性心肌缺血的动物模型,观察间歇性低压低氧预处理的促血管生成作用。方法: 成年雄性新西兰家兔29只,体重2.0-2.5 kg,随机分为3大组:正常组(N组,n=7),对照组(C组,n=11)和间歇性低氧预处理组(H组,n=11)。C组、H组行冠状动脉左前降支部分结扎,H组动物进行间歇性低氧预处理(5 000 m,6 h/d,连续7 d者为H1组,42 d者为H2组),按计划完成实验后测定血管内皮生长因子mRNA (VEGFmRNA)、低氧诱导因子-1 α mRNA (HIF-1 α mRNA)、内皮细胞一氧化氮合酶mRNA(eNOSmRNA)及血管内皮生长因子(VEGF)蛋白表达及毛细血管密度。结果: 间歇性低氧预处理VEGF mRNA、HIF-1 α mRNA、eNOS mRNA及VEGF蛋白持续增加,毛细血管密度增高。结论: 间歇性低氧预处理能促进慢性缺血心肌内的血管生成。     

The effect of spermatic vessel ligation on testicular nitric oxide levels and germ cell-specific apoptosis in rat testis

Management of high testis may vary but the most popular method in surgical treatment is the Fowler-Stephens maneuver. The aim of the present study was to investigate the effects of spermatic vessel ligation on testicular nitric oxide (NO) levels, expression of inducible nitric oxide synthase (iNOS), and endothelial nitric oxide synthase (eNOS) and germ cell-specific apoptosis in both ipsilateral and contralateral testes in rats. Twenty-eight animals were randomly allocated into four groups (n=7 each). The spermatic vessels were ligated as a simulation of the Fowler-Stephens maneuver. The groups of animals were sacrificed at 2 h (group 1), 4 h (group 2) and 24 h (group 3) after ligation, respectively. Sham-operated animals served as controls (group 4). Biochemical assessment of testicular NO levels was performed by the Griess method. iNOS and eNOS expression and apoptosis were studied in ipsilateral and contralateral testes. Testicular NO levels at 24 h after the simulated Fowler-Stephens maneuver were found to be significantly increased in both ipsilateral and contralateral testes when compared with the sham-operated group. eNOS expression was clearly increased in ipsilateral testes, whereas moderate expression was detected in the contralateral seminiferous tubules at 24 h after ligation. Mild focal iNOS immunostaining was also observed in seminiferous tubules of the ipsilateral testis at 24 h after the simulated Fowler-Stephens maneuver. Apoptosis was dramatically increased in ipsilateral testes; however, it was only detected in single cells in the contralateral side at 24 h after ligation. In conclusion, the simulated Fowler-Stephens maneuver induces testicular nitric oxide synthesis and germ cell-specific apoptosis in the ipsilateral testis. These results suggest that high levels of NO induce apoptosis and may impair spermatogenesis thus explaining the unsuccessful outcome of the Fowler-Stephens maneuver.