绿茶多酚抑制LDL诱导的血管平滑肌细胞增殖

The proliferation and migration of vascular smooth muscle cells (VSMCs) is one of the major mechanisms of intimal thickening in atherosclerosis and post-angioplasty restenosis. Elevated plasma levels of low-density lipoprotein (LDL) have been implicated in the pathogenesis of atherosclerotic vascular diseases. The purpose of this study was to determine the effects of green tea polyphenols on the proliferation and p44/42 mitogen-activated protein kinase (MAPK) activity in rat VSMCs simulated by native LDL. Rat aortic VSMCs were cultured and treated with LDL (100 microg/ml) in the absence or presence of green tea polyphenols, and the cell proliferation was subsequently quantified by non-radioactive MTS/PES assay and the cell cycle analyzed by flow cytometry. The p44/42 MAPK activity was evaluated by immunoblotting using anti-p44/42 phospho-MAPK antibody. Compared with the cells without polyphenol treatment, the proliferation of the VSMCs induced by LDL was dose-dependently inhibited by green tea polyphenols (P<0.05), with more numerous cells in G(0)G(1) phase (P<0.05) as shown by flow cytometry analysis. LDL significantly enhanced the p44/42 MAPK activity, an effect obviously inhibited by green tea polyphenols (at 100 microg/ml). These results suggest that green tea polyphenols can inhibit high levels of LDL-induced proliferation of phosphorylated p44/42 MAPK expression in rat VSMCs. Green tea polyphenols may, therefore, offer vascular protection by inhibiting VSMC growth in response to hypercholesterolemia.     

绿茶多酚抑制晚期糖基化终产物诱导的大鼠血管平滑肌细胞增殖

目的本研究观察绿茶多酚对晚期糖基化终产物(AGEs)刺激下离体大鼠胸主动脉血管平滑肌细胞增殖的影响。方法体外培养大鼠主动脉血管平滑肌细胞(VSMCs)应用不同浓度的AGEs分别刺激VSMCs并设立对照组进行比较,将不同剂量的绿茶多酚与AGEs共同作用并设立对照组进行比较,采用非放射性的MTS/PES法确定血管平滑肌细胞的增殖状态。结果与对照组相比,晚期糖基化终产物对血管平滑肌细胞增殖具有明显的刺激作用。在晚期糖基化终产物刺激下,绿茶多酚可明显抑制血管平滑肌细胞的生长。AGEs对p44/42 MAPK磷酸化蛋白表达有显著的增强作用,此作用可被绿茶多酚抑制。结论本研究提示绿茶多酚可抑制晚期糖基化终产物诱导的血管平滑肌细胞增殖及p44/p42 MAPK磷酸化蛋白的表达。     

绿茶多酚抑制晚期糖基化终产物诱导的大鼠血管平滑肌细胞增殖

目的 本研究观察绿茶多酚对晚期糖基化终产物(AGEs)刺激下离体大鼠胸主动脉血管平滑肌细胞增殖的影响。方法 体外培养大鼠主动脉血管平滑肌细胞(VSMCs)应用不同浓度的AGEs分别刺激VSMCs并设立对照组进行比较．将不同剂量的绿茶多酚与AGEs共同作用并设立对照组进行比较，采用非放射性的MTS／PES法确定血管平滑肌细胞的增殖状态。结果 与对照组相比，晚期糖基化终产物对血管平滑肌细胞增殖具有明显的刺激作用。在晚期糖基化终产物刺激下．绿茶多酚可明显抑制血管平滑肌细胞的生长。AGEs对p44／42MAPK磷酸化蛋白表达有显著的增强作用，此作用可被绿茶多酚抑制。结论 本研究提示绿茶多酚可抑制晚期糖基化终产物诱导的血管平滑肌细胞增殖及p44／p42 MAPK磷酸化蛋白的表达。     

丝裂素活化蛋白激酶磷酸酶-1对血管平滑肌细胞增殖的影响及其机制

目的 研究丝裂素活化蛋白激酶磷酸酶-1(MKP1)对血管平滑肌细胞增殖的影响及机制。方法 转染MKP1质粒72h后，收集培养的血管平滑肌细胞(VSMC)，利用P^42／P^44磷酸化抗MAPK抗体通过免疫印迹法测定MAPK活性，用流试细胞仪测定细胞周期、细胞周期素和P27蛋白的表达。结果 转染MKP1质粒后，MAPK活性明显下降，VSMC阻滞于G0-G1期，同时抑制了细胞周期素D、E的表达，P27蛋白表达却明显增加。结论 MKP1抑制VSMC增殖可能是通过降低MAPK活性，抑制细胞周期素表达和增加P27蛋白表达途径实现的。     

阿司匹林对血管内皮细胞增殖及磷酸化p44／42 MAPK表达的抑制作用

OBJECTIVE: To observe the effects of aspirin on vascular endothelial cell proliferation in vitro and on the activity of p44/p42 mitogen-activated protein kinase (MAPK) phosphorylation. METHODS: ECV 304 cells cultured in vitro were treated with aspirin (1, 2, 5, and 10 mmol/L, respectively) and observed for their proliferation in comparison with the control group. The ratio of cell proliferation was determined by non-radioactive MTS/PES assay. The expression of phosphorylated p44/42 MAPK protein was evaluated by the immunoblotting technique using anti-p44/42 phospho-MAPK antibody. RESULTS: The proliferation rate of the endothelial cell was 1.533+/-0.286 in the control group, and 0.459+/-0.107, 0.708+/-0.125, 0.953+/-0.149 and 1.253+/-0.225 in aspirin-treated groups corresponding to aspirin concentrations of 10, 5, 2 and 1 mmol/L, respectively. It was shown that aspirin significantly inhibited the vascular endothelial cell proliferation at the concentration above 1 mmol/L (P<0.05), in a dose-dependent manner as compared with the control group (P<0.05). The expression of phosphorylated p44/42 MAPK protein was significantly inhibited by aspirin. CONCLUSIONS: Aspirin decreases vascular endothelial cell proliferation, and arrest of endothelial cell proliferation may be an important mechanism by which aspirin produces protective effect against acute coronary disease.     

血管紧张素转换酶2基因转染抑制平滑肌细胞增殖

目的 通过血管紧张素转换酶2(ACE2)基因转染大鼠血管平滑肌细胞(VSMC),观察其对血管紧张素Ⅱ(AngⅡ)促VSMC增殖的影响.方法 将大鼠VSMC分为正常细胞组、AngⅡ组、空载体+AngⅡ组及pm-ACE2+AngⅡ组,通过CCK8细胞计数试剂盒和流式细胞仪检测各组细胞周期,观察ACE2基因转染对AngⅡ促VSMC增殖效应的影响.结果 与正常细胞组相比,AngⅡ组细胞计数明显增高,pm-ACE2+AngⅡ组与AngⅡ组相比显著降低(0.535±0.004比0.866±0.026,P＜0.05);同时,AngⅡ组在G0/G1期细胞的百分率明显降低(58.80%±2.00%,P＜0.05),S期的则显著增高(35.90%±1.00%,P＜0.05),与AngⅡ组相比,pmACE2+AngⅡ组在G0/G1期的百分率明显升高(63.90%±1.40%,P＜0.05),S期则显著降低(27.80%±0.46%,P＜0.05).结论 ACE2基因转染能抑制AngⅡ的促VSMC异常增殖效应.

Abstract：

Objective To investigate the effect of Ang Ⅱ on the proliferation of vascular smooth muscle cell (VSMC) in rats after the transfection of ACE2 gene. Methods pm-ACE2 was transfected into the cultured VSMC by Lipofectamine 2000. The normal cell group, Ang Ⅱ group and pcDNA3. 1/Hygro( + )transfected + Ang Ⅱ group were taken as controls respectively. After the transfection of ACE2 gene, the cell proliferative effect of Ang Ⅱ on VSMC was investigated by cell counting kit-8 (CCK8) and cell cycle detection by fluorescence activated cell sorter (FACS). Results The (optical density) OD value of Ang Ⅱgroup was obviously higher than that of other groups. And it was obviously lower in the pm-ACE2 + Ang Ⅱgroup than the Ang Ⅱ group (0. 535 ± 0. 004 vs 0.866 ± 0.026, P ＜ 0. 05 ). Compared with other groups, the G0/G1 stage percentage of VSMC was obviously lower in the Ang Ⅱ group(58. 80% ±2. 00%, P ＜0. 05)while the percentage of S stage was obviously higher ( 35.90% ± 1.00%, P ＜ 0.05 ). Compared with the Ang Ⅱ group , the G0/G1 stage percentage of VSMC was obviously higher( 63. 90% ± 1.40%, P ＜ 0. 05 ) in the pm-ACE2 + Ang Ⅱ group while the percentage of S stage was obviously lower( 27.80% ± 0. 46%, P ＜0. 05 ). Conclusion The over-expression of ACE2 gene can inhibit the proliferation of Ang Ⅱ-induced VSMC.     

L-精氨酸及牛磺酸对溶血性磷脂酸诱导的血管平滑肌增殖的作用

目的 :观察牛黄酸 (TAU)及L -精氨酸 (L -Arg)对溶血性磷脂酸 (LPA)诱导的血管平滑肌 (VSMC)增殖的影响并探讨其可能的机制。方法 :贴块法培养大鼠胸主动脉VSMC ;3H -胸腺嘧啶 (3H -TdR)掺入测定VSMCDNA合成 ;γ - 32 P -ATP标记的同位素法测定丝裂素活化蛋白激酶 (MAPK)活性。结果 :与对照组相比 ,LPA(10 - 8mol L)可分别使VSMC3H -TdR掺入和MAPK活性增高 5 8%和 16 4 % (P <0 .0 1)。L -Arg及TAU均能浓度依赖性地抑制LPA诱导的VSMC3H -TdR掺入和MAPK激活。混合应用牛磺酸和L -精氨酸对LPA诱导的VSMC增殖及MAPK活性的抑制作用显著大于单用L -Arg和TAU(P <0 .0 1)。结论 :L -Arg及TAU均能抑制LPA诱导的VSMC增殖和MAPK激活 ,而合用L -Arg及TAU对抑制LPA诱导的VSMC增殖及MAPK活性具有协同和叠加效应     

TRPC6介导血管紧张素Ⅱ诱导血管平滑肌细胞的增殖

目的 探讨瞬时受体电位阳离子通道6(TRPC6)在血管紧张素Ⅱ(AngⅡ)诱导大鼠的血管平滑肌细胞(VSMC)增殖中的作用.方法 应用组织贴块法培养大鼠主动脉VSMC,用AngⅡ刺激VSMC建立细胞增殖模型,应用Western blot技术检测平滑肌细胞的TRPC6表达水平,采用四甲基偶氮唑蓝比色法(MTT法)检测不同浓度的SKF96365(TRPC通道阻断剂)和不同浓度的flufenamic acid(TRPC6激动剂)对VSMC增殖的影响.结果 Western blot显示在VSMC中TRPC6通道蛋白表达水平很高.用SKF96365(10、50、100 μmol/L)阻断TRPC6通道后.经过72h的作用抑制AngⅡ诱导的VSMC的增殖,且呈剂量依赖性.用flufenamic acid(10、20、40 μmol/L)激动TRPC6通道,经过24 h的作用促进了VSMC的增殖.结论 在AngⅡ诱导大鼠的血管平滑肌细胞增殖中,TRPC6通道起着很重要的作用.     

血管紧张素Ⅱ诱导血管平滑肌细胞肥厚过程中MAPK对细胞周期素依赖性激酶抑制因子的调节作用

目的观察在血管紧张素Ⅱ(AngⅡ)诱导血管平滑肌细胞(VSMC)肥厚过程中,丝裂原活化蛋白激酶(MAPK)活性和细胞周期素依赖性激酶抑制因子p27、p21、p57蛋白表达量的变化,探讨MAPK对细胞周期素依赖性激酶抑制因子的调节作用。方法分离SD大鼠主动脉中层平滑肌,贴壁法培养平滑肌细胞,无血清培养基培养静止后,加入AngⅡ1×10-6 mol/L和/或豆蔻酸佛波酰乙酯(PMA)20nmol/L,以无血清培养基培养的VSMC作对照。在刺激后90min收集细胞,用免疫沉淀法检测MAPK活性的改变。在刺激后6和24h收集细胞,用Western blotting法检测p27、p57和p21蛋白表达量。结果AngⅡ可以使MAPK活性升高,但其升高幅度较低(仅较对照组增加了138%),未能抑制p27蛋白的表达,不能使VSMC增殖。PMA和AngⅡ共同作用时,可以轻度抑制p27蛋白的表达,但仍未能使VSMC增殖。结论MAPK通路是VSMC胞外增殖肥厚刺激信号进入核内的一条重要信息传导通路。     

阿司匹林对血管内皮细胞增殖及磷酸化p44/42MAPK表达的抑制作用

目的 观察阿司匹林对体外培养的血管内皮细胞的增殖和磷酸化p44/42丝裂素活化蛋白激酶(MAPK)表达的影响。方法 体外培养血管内皮细胞株ECV304,应用1、2、5、10 mmol/L的阿司匹林分别作用并设立对照进行比较,采用MTS/PES法确定ECV304细胞的增殖状态。利用p44/42磷酸化抗MAPK抗体的蛋白免疫印迹法测定磷酸化p44/42 MAPK蛋白表达。结果 各组的细胞增殖率分别为对照组1.533±0.286,阿司匹林1 mmol/L组1.253±0.225,2 mmol/L组0.953±0.149,5 mmol/L组0.708±0.125,10 mmol/L组0.459±0.107。统计分析显示低至1 mmol/L的阿司匹林仍能明显抑制ECV304细胞的增殖(P<0.05),并呈现剂量依赖性。阿司匹林对ECV304细胞的磷酸化p44/p42 MAPK表达有显著的抑制作用(P<0.05)。结论 阿司匹林对体外培养的血管内皮细胞的增殖和内皮细胞中磷酸化p44/42 MAPK的表达均有明显的抑制作用。     

茶多酚对大鼠血管平滑肌细胞增殖的影响

目的　探讨茶多酚对离体大鼠胸主动脉血管平滑肌细胞增殖的影响。方法　体外培养大鼠主动脉血管平滑肌细胞 ,应用不同剂量的茶多酚作用 2 4 h后 ,采用 MTS/ PES法确定血管平滑肌细胞的增殖状态。应用流式细胞术测定细胞周期。结果　与对照组相比 ,茶多酚对血管平滑肌细胞增殖具有明显的抑制作用 (P<0 .0 0 1)。流式细胞术检测结果表明 ,茶多酚可以使血管平滑肌细胞大部分处于 G0 / G1 期 ,与对照组相比有明显差异 (P<0 .0 5 ) ,并且可以诱导其凋亡。结论　茶多酚可明显抑制离体大鼠血管平滑肌细胞的增殖。     

ORC1基因RNA干扰对大鼠血管平滑肌细胞增殖的影响

目的以RNA干扰抑制血管平滑肌细胞(vascu lar smooth musc le cells,VSMCs)ORC1基因,探讨ORC1基因表达抑制后VSMCs增殖的变化。方法实验设置正常对照组、阴性siRNA组及阳性(ORC1 A、ORC1 B、ORC1 C)siR-NA组。应用W estern b lot检测ORC1基因表达的变化;应用MTT比色试验、3H-TdR掺入试验检测VSMCs增殖的情况。免疫细胞化学染色观察增殖细胞核抗原(proliferating cell nuc lear antigen,PCNA)表达。结果①siRNA转染后,3个阳性siRNA转染组ORC1基因表达水平均降低,尤以第2对阳性siRNA抑制效果最为显著,而空白对照组及阴性对照组间ORC1基因表达水平无显著差异。②siRNA转染使ORC1表达减弱后,VSMCs的MTT吸光度值3、H-TdR掺入量和PCNA表达量均较空白对照组及阴性对照组显著降低。结论RNA干扰介导的ORC1基因沉寂可显著抑制VSMCs增殖。     

内皮祖细胞对血管平滑肌细胞增殖的影响

目的：观察内皮祖细胞(endothelial progenitor cell,EPCs)对血管平滑肌细胞(vascular smooth muscle cell,VSMCs)增殖的影响。方法：采用6%羟乙基淀粉沉降红细胞和密度梯度离心法分离人脐血单个核细胞,EGM-2细胞培养基进行培养,诱导单个核细胞贴壁并向EPCs分化;采用荧光显微镜双染色、流式细胞术鉴定EPCs,间接免疫荧光检测VSMCs收缩表型标志物α-SM-actin和calponin的表达;Transwell培养板建立早期EPCs和大鼠VSMCs共培养模式,以20%胎牛血清刺激VSMCs增殖,分别共培养6,12,24,48,72 h后收集VSMCs,采用BrdU标记法、蛋白定量、流式细胞术分析VSMCs DNA合成能力、细胞总蛋白含量以及细胞周期进程。结果：从脐血单个核细胞成功培养了EPCs。EPCs和大鼠VSMCs共培养12,24,48,72 h后,VSMCs DNA合成能力、细胞总蛋白含量均较对照组明显降低(P＜0.05),其中以48 h最明显;流式细胞术显示,共培养组VSMCs细胞周期中S期细胞所占百分率较对照组显著降低(P＜0.05),而细胞周期中G1期细胞所占百分率均相应高于对照组(P＜0.05),其中均以48 h最明显。结论：早期EPCs能够抑制VSMCs增殖。     

胰岛素对大鼠血管平滑肌细胞增殖及胶原蛋白合成的影响

目的 观察胰岛素对分离培养的大鼠血管平滑肌细胞(vascular smooth muscle cells,VSMCs)增殖及胶原蛋白合成的影响.方法 采用大鼠的腹主动脉血管平滑肌细胞分离培养,应用3H-TdR和3H-脯氨酸掺人方法检测胰岛素对大鼠VSMCs干预后,VSMCs内DNA合成以及胶原蛋白合成.结果 胰岛素可促进处于静止状态的大鼠VSMCs DNA及胶原蛋白的合成,并呈现明显的浓度依赖关系,在40 nmol/L的浓度时DNA及胶原蛋白的合成达到高峰,DNA及胶原蛋白分别处于36 h和48 h时合成最为显著.结论 胰岛素可明显促进培养的VSMCs增殖及胶原蛋白的合成.     

超声造影剂对血管平滑肌细胞增殖的影响

目的观察超声造影剂对大鼠胸主动脉血管平滑肌细胞(VSMC)增殖的影响.方法血小板衍生生长因子-BB(PDGF-BB)刺激大鼠VSMC建立细胞增殖模型.在培养基中加或不加脂质体微泡(1μl/ml),采用台盼蓝排斥染色、MTT法和3H-TdR掺入法检测不同强度、时间的连续波超声辐照对VSMC的毒性作用以及增殖和DNA合成的抑制作用.结果频率1MHz、声强0.3W/cm2的超声联合造影荆辐照VSMC,未见细胞溶解,24h后细胞核蓝染率较辐照即刻显著降低(P＜0.01);辐照30s即可显著抑制PDGF-BB所致的VSMC增殖和DNA合成(P＜0.05),随着辐照时间延长,抑制作用增强,60s时抑制程度最强(P＜0.01).结论低强度超声辐照下超声造影荆的空化效应可抑制VSMC增殖,并对细胞膜有暂时性的损伤作用.     

自噬对血管平滑肌细胞增殖的影响

血管平滑肌细胞异常增殖是血管增殖性疾病的病理基础,自噬是真核生物维持细胞内环境稳态的一种自我保护机制。近年来的研究发现,自噬参与多种细胞因子、血管活性物质、剪切应力、ncRNA等诱导的血管平滑肌细胞增殖,一些抗血管增生性疾病的药物往往通过调节自噬通量和自噬活性发挥抗血管平滑肌细胞增殖作用。本文综述了自噬对血管平滑肌细胞增殖的影响,为探索血管增生性疾病的病理生理机制提供新的思路。