Effects of Ang-( 1-7 ) on the apoptosis of cultured endothelial cells induced by Ang Ⅱ

Objective To investigate the effect of Ang-(1-7) on the apoptosis in human umbilical vein endothelial cells (HUVECs) induced by Ang Ⅱ.Methods HUVECs were isolated and cultured.Cultured HUVECs were incubated for 24 h with Ang-(1-7), Ang Ⅱ, Ang-(1-7) A-779, Ang-(1-7) + Ang Ⅱ, A-779 + Ang Ⅱ + Ang-( 1-7), respectively.Cultured HUVECs without incubating stimulator were chosen as controls.The apoptosis of endothelial cells were detected by flow cytometry.Results The apoptosis of endothelial cells in HUVECs were upregulated by AngⅡ ( 10-6 mol/L) (25.60% ±3.17% vs 2.32% ±0.24%, P ＜0.005).Compared with the AngⅡ group, Ang-(1-7) dose-dependently inhibited the apoptosis of endothelial cells in HUVECs ( (20.04% ± 2.21% ,16.04% ± 1.32 %, 10.04% ±2.05,7.79% ±1.50% vs AngⅡ group 25.60% ±3.17%, P ＜0.05 , P ＜0.05).The effects of Ang-(1-7) could be blocked by A-779 (23.37% ±0.75% vs 20.04% ± 2.21%, 16.04% ± 1.32,10.04% ± 2.05% ,7.79%± 1.50%, P ＜ 0.05 ).Conclusion Ang-(1-7) can attenuate the apoptosis of endothelial cells induced by Ang Ⅱ in HUVECs in a dose-dependent manner.The effects of Ang-(1-7) could be blocked by A-779( P＜0.05).     

血管紧张素－（1—7）对血管紧张素Ⅱ诱导人脐静脉内皮细胞凋亡的影响

目的 观察血管紧张素（1-7）[Ang-（1-7）]对血管紧张素Ⅱ（AngⅡ）诱导人脐静脉内皮细胞（HUVECs）凋亡的影响.方法 采用胰蛋白酶消化法原代培养HUVECs,取2～5代用于实验,培养的HUVECs随机分为：对照组、AngⅡ组、Ang-（1-7）组、AngⅡ＋Ang-（1-7）组、AngⅡ＋Ang-（1-7）＋A-779组,用吖啶橙（AO）/溴乙锭（BE）法观察细胞凋亡的形态学变化,用流式细胞术检测内皮细胞的凋亡率.结果 （1）AngⅡ（10-6 mol/L）可以诱导HUVECs凋亡率明显增加,与对照组相比差异有统计学意义（25.60%±3.17% vs 2.32%±0.24%,P＜0.005）;不同浓度的Ang-（1-7）（10-9～10-6 mol/L）呈剂量依赖性抑制AngⅡ所诱导的内皮细胞的凋亡,与AngⅡ组相比差异有统计学意义（20.04%±2.21%,16.04%±1.32%,10.04%±2.05%,7.79%±1.50%,P＜0.05）;力Ⅱ用Ang-（1-7）特异性受体拮抗剂A-779可阻断Ang-（1-7）的上述效应,与AngⅡ＋Ang-（1-7）组比较差异有统计学意义（23.37%±0.75%vs 20.04%±2.21%,16.04%±1.32%,10.04%±2.05%,7.79%±1.50%,P＜0.05）.结论 AngⅡ可诱导内皮细胞凋亡增加,Ang-（1-7）呈浓度依赖性抑制AngⅡ的上述效应,并且是通过其特异性受体Mas发挥作用.     

Ang1-7抑制AngⅡ诱导子痫前期的作用及机制研究

目的探讨血管紧张素1-7(Ang1-7)抑制血管紧张素Ⅱ(AngⅡ)诱导子痫前期的作用及机制。方法收集足月经阴道分娩子痫前期患者及足月经阴道分娩正常妊娠孕产妇胎盘组织标本。通过RT-PCR检测胎盘中AngⅡ及Ang1-7 mRNA表达情况。检测胎盘组织中滋养细胞衰老情况:检测细胞周期变化,检测SA-β-gal染色情况,通过RT-PCR方法检测P53、P21、白细胞介素-1β(IL-1β)等细胞因子表达水平变化。用AngⅡ、Ang1-7及Ang1-7抑制剂A779刺激滋养细胞系,检测滋养细胞衰老情况。结果与正常妊娠孕产妇比较,子痫前期患者胎盘AngⅡmRNA表达水平升高,Ang1-7 mRNA表达水平降低,多数细胞阻滞于S期,进入G2/M期细胞数减少,细胞活性降低,SA-β-Gal染色阳性细胞比例增加,P53、P21、IL-1β等细胞因子mRNA表达水平升高。与对照组相比,AngⅡ处理后,多数细胞阻滞于S期,进入G2/M期细胞数减少,细胞活性降低,SA-β-Gal染色阳性细胞比例增加。与AngⅡ组相比,AngⅡ+Ang1-7处理后,进入G2/M期细胞增加,滋养细胞活性增加,SA-β-Gal染色阳性细胞比例降低。与AngⅡ+Ang1-7组相比,AngⅡ+Ang1-7+A779处理后,多数细胞阻滞于G0/G1S期,进入S期、G2/M期细胞数减少,滋养细胞活性降低,SA-β-Gal染色阳性细胞比例增加。结论AngⅡ可通过促进滋养细胞衰老加速而导致子痫前期发生,Ang1-7可以抑制AngⅡ的上述作用。     

血管紧张素-(1-7)抑制血管紧张素Ⅱ诱导的大鼠系膜细胞增殖

目的 探讨血管紧张素-(1-7)[Ang-(1-7)]对血管紧张素Ⅱ(AngⅡ)诱导大鼠系膜细胞(GMC)增殖的影响。方法 在AngⅡ诱导培养的GMC中，应用Ang-(1-7)，通过[^3H]-Thymidine及[^3H]-Leucine掺入分别测定GMC的DNA、蛋白质合成；结晶紫染色检测细胞数目，观察系膜细胞增殖情况；分别用特异性AngⅡ受体1(AT1受体)拮抗剂[Sar^1，Ⅱe^8]-AngⅡ和血管紧张素Ⅱ受体2(AT2受体)拮抗剂PD123319与Ang-(1-7)共同培养，探讨Ang-(1-7)是否通过AngⅡ受体发挥作用。结果 Ang-(1-7)呈剂量依赖性抑制AngⅡ诱导GMC的DNA、蛋白质合成及细胞数目增加；[Sar^1，Ⅱe^8]-AngⅡ和PD123319不影响Ang-(1-7)的上述作用。结论 Ang-(-1-7)能抑制基础和AngⅡ诱导的GMC增殖，其作用的发挥不通过AngⅡ的AT1和AT2受体介导。     

Effects of zoledronic acid on the expression of HIF-1α and VEGF in the osteosarcoma cell line LM8 under hypoxic condition

Objective To investigate the effects of zoledronic acid on the expression of HIF-1α and VEGF in osteosarcoma LM8 cell line under hypoxic condition. Methods The hypoxic culture model was established. After LM8 cells were treated with zoledronic acid, semi-quantitative PCR was used to assess the expression of HIF-1α and VEGF mRNA. The expression of HIF-lct and VEGF protein was de-tected by immunohistochemical staining and ELISA respectively. Results Compared with cells in normoxic conditions, cells in the hypoxic environment and cells treated with zoledronic acid in the hypoxic condition did not show a significant change in the mRNA level of HIF-1α(P >0. 05). However, the protein expression of HIF-1α was markedly decreased in the cells treated with zoledronic acid in the hypoxic envi-ronment. In contrast, both mRNA and protein expression levels of VEGF were down-regulated in the zoledronic acid treatment hypoxic group (P <0.05). Conclusion Under hypoxic conditions in vitro, zoledronic acid inhibited the expression of HIF-1α protein, which decreased VEGF mRNA level and protein expression in osteosarcorna LM8 cell line.     

血管紧张素-(1-7)对压力负荷增高大鼠血管紧张素Ⅱ及受体的影响

目的探讨血管紧张素-(1-7)[Ang-(1-7)]对压力负荷增高大鼠血管紧张素Ⅱ及受体的影响。方法采用腹主动脉缩窄术制成压力负荷增高大鼠模型,45只SD大鼠随机分为假手术组、模型对照组、Ang-(1-7)治疗组。Ang-(1-7)治疗组大鼠通过颈静脉插管和置入式微量泵,持续给予Ang-(1-7),剂量为25μg·kg-1·h-1,共4周。假手术组和模型对照组经微量泵只给予同量的生理盐水。术后4周检测大鼠左心室重量/体重比、血浆及心肌血管紧张素Ⅱ浓度、并采用逆转录-聚合酶链反应检测左心室心肌血管紧张素Ⅱ1型(AT1)、2型(AT2)受体mRNA的表达水平。结果与假手术组比较,模型对照组术后4周心肌血管紧张素Ⅱ浓度及心肌AT1受体mRNA的表达水平明显增高,左心室重量/体重比也明显增高;与模型对照组比较,Ang-(1-7)治疗组术后4周血浆及心肌血管紧张素Ⅱ浓度无明显变化,但心肌中AT1受体mRNA的表达水平降低,左心室重量/体重比也明显降低。心肌中AT2受体mRNA的表达在3组中无明显差异。结论外源性Ang-(1-7)可减轻压力负荷增高所致的心肌肥厚,可能与它抑制心肌中AT受体表达有关。     

全反式视黄酸对体外培养的人体大隐静脉内膜平滑肌细胞增殖与凋亡的影响

目的研究全反式视黄酸(atRA)对体外培养的人体大隐静脉内膜增厚、平滑肌细胞增生与凋亡的影响。方法30小段(1 cm长)人体大隐静脉(HSV),随机分成HSV组、atRA组和对照组(n=10),atRA组和对照组均体外培养14 d。atRA组:培养液中含atRA100μM;对照组:培养液中含同等量无水酒精(atRA溶剂)。对HSV组及培养后的atRA组、对照组标本进行取材固定,M asson染色,免疫组化测定增殖细胞核抗原(PCNA)及TUNEL法检测平滑肌细胞凋亡,计算机图象分析仪测量血管内膜厚度、计算内膜增生指数及细胞增殖和凋亡百分比。结果体外培养人体大隐静脉能产生明显的内膜增生和平滑肌细胞增殖(P<0.05);atRA组内膜厚度、增生指数及PCNA阳性细胞百分数均明显低于对照组(P<0.05)。而凋亡细胞百分数则明显高于对照组(P<0.05)。结论atRA可以抑制体外培养人体大隐静脉内膜增厚及平滑肌细胞增生,促进平滑肌细胞凋亡。     

血管紧张素-(1-7)对血管紧张素Ⅱ诱导的子宫内膜上皮细胞增殖和转分化的影响

目的了解血管紧张素Ⅱ(AngⅡ)和血管紧张素-(1-7)[Ang-(1-7)]对子宫内膜上皮细胞(EECs)增殖和活性的影响。方法体外分离、培养和鉴定EECs。试验分4组:对照组、AngⅡ组、Ang-(1-7)组和AngⅡ+Ang-(1-7)组,采用噻唑蓝(MTT)法观察各组EECs增殖的影响;免疫细胞化学染色法检测各组EECs中的α-平滑肌肌动蛋白(α-SMA)和上皮性钙粘附素(E-cadherin)的表达水平;用酶联免疫吸附试验(ELISA)检测各组上清液中Ⅰ型胶原(ColⅠ)和纤粘连蛋白(FN)的含量。结果在48和72 h时,AngⅡ组EECs数量明显增加;细胞中α-SMA蛋白的表达升高(77.67±1.78),E-cadherin的表达降低(26.56±2.09);ColⅠ和FN分泌均增加(0.832 0±0.029 2,0.752 8±0.071 2),与对照组相比,其差异有统计学意义(P<0.05)。Ang-(1-7)+AngⅡ组的EECs数量减少;细胞胞质中α-SMA的含量降低(33.58±1.34),而E-cadherin的含量升高(66.86±2.76);ColⅠ和FN分泌均减少(0.635 5±0.026 5,0.557 3±0.038 5),与AngⅡ组相比,其差异有统计学意义(P<0.05)。结论 Ang-(1-7)不仅可拮抗AngⅡ刺激的EECs增殖,还可抑制其活性。