Fluvastatin enhances apoptosis in cytokine-stimulated vascular smooth muscle cells.

Hydroxymethylglutaryl coenzyme A reductase inhibitors (statins) have been shown to attenuate proliferation of vascular smooth muscle cells (VSMCs) by mechanisms independent of lipid reduction. In the current study, we investigated the effect of lipophilic and hydrophilic statins (fluvastatin and pravastatin) on apoptosis in unstimulated or cytokine-stimulated VSMCs. The presence of apoptosis in rat VSMCs was evaluated by electrophoresis of DNA fragments and 4'6'-diamidine-2'-phenylindole staining and quantified by flow cytometry. Fluvastatin but not pravastatin enhanced apoptosis in interleukin-1beta-stimulated VSMCs. The proapoptotic effect of fluvastatin was fully reversed by mevalonate and geranylgeranyl-pyrophosphate, and partially by farnesyl-pyrophosphate, but not by squalene. Inhibition of the extracellular signal-regulated protein kinase (ERK1/2) pathway significantly increased fluvastatin-enhanced apoptosis, whereas inhibition of the p38-mitogen-activated protein kinase (MAPK) pathway significantly prevented this increase. However, fluvastatin showed no effect on the activity of ERK1/2 and p38-MAPK. Furthermore, fluvastatin-induced apoptosis was inhibited by YVAD-FMK (a caspase-1/interleukin-1beta-converting enzyme-like protease inhibitor) and DEVD-FMK (a caspase-3/CPP32 inhibitor), indicating involvement of an important segment in the apoptosis signaling pathway. These findings suggest that fluvastatin enhances apoptosis in cytokine-stimulated VSMCs and that protein prenylation, MAPK (ERK1/2 and p38-MAPK), and caspases are critically involved in the pathways of fluvastatin-enhanced apoptosis.     

曲古菌素A抑制血管平滑肌增殖和诱导凋亡的研究

目的观察曲古菌素A(TrichostatinA,TSA)体外抑制血管平滑肌细胞(VSMC)增殖和诱导凋亡的作用。方法采用MTT比色法和BrdU参入法观察TSA对血清诱导的VSMC增殖的抑制作用;采用流式细胞仪和检测细胞周期蛋白表达的方法观察TSA对VSMC细胞周期的影响;采用测定DNA片段和活化caspase-3表达的方法观察TSA诱导VSMC发生凋亡的作用。结果小剂量TSA抑制血清诱导的VSMC增殖而无明显的细胞毒作用,大剂量TSA激活caspase-3并诱导VSMC发生凋亡。TSA干预可延缓血清诱导VSMC进入S期,此效应与抑制cyclinD1和cyclinA表达有关。结论TSA能抑制血清诱导的VSMC增殖,使VSMC停滞于静止期,大剂量条件下诱导VSMC凋亡。TSA有望成为治疗血管增殖性疾病的新策略。     

福辛普利对平滑肌细胞凋亡及凋亡调控基因的影响

目的：探讨血管紧张素Ⅱ在不同浓度和不同作用时间下对血管平滑肌细胞凋亡及凋亡调控基因表达的作用，并研究福辛普利对其的影响。方法：采用流式细胞技术测定在不同浓度和不同作用时间血管紧张素Ⅱ作用下血管平滑肌细胞凋亡率及凋亡调控基因Fas、Bcl-2表达的变化和福辛普利对其的影响。结果：血管紧张素Ⅱ对血管平滑肌细胞凋亡和凋亡调控基因表达有较明显的诱导作用。福辛普利可抑制AngⅡ作用，对细胞凋亡有一定的影响，同时可影响凋亡调控基因的表达。结论：血管紧张素Ⅱ具有一定的的促进血管平滑肌细胞凋亡作用和调节凋亡调控基因表达的作用，尤其大剂量作用较明显。而福辛普利可明显抑制AngⅡ对血管平滑肌细胞的作用。     

色满卡林对自发性高血压大鼠血管平滑肌细胞凋亡的影响

目的：观察色满卡林对自发性高血压大鼠(SHR)血管平滑肌细胞(VSMCs)凋亡的影响。方法：30只12 wk龄SHR,随机分为高血压组、色满卡林组,另设正常对照组。色满卡林组给予色满卡林0.6 mg·kg~(-1)·d~(-1),分2次灌胃；另2组每日给予等量的生理盐水,共16 wk。监测尾动脉收缩压。用免疫组化法检测Bcl-2,Bax和PCNA蛋白表达。荧光标记TUNEL法检测VSMCs凋亡,计算VSMCs凋亡指数(SMAI)。结果：高血压组与正常对照组比较,收缩压明显增高(P＜0.05)；VSMCs中的Bcl-2,PCNA蛋白表达明显增强(P＜0.05)；SMAI明显减少(P＜0.01)；Bax蛋白表达2组间差异无显著意义(P＞0.05)。与高血压组比较,色满卡林组尾动脉收缩压呈降低趋势,但差别无显著意义(P＞0.05)；VSMCs的Bcl-2和PCNA蛋白的表达减少(P＜0.05),Bcl-2/Bax比值下降；SMAI增加(P＜0.05)。结论：色满卡林促进了SHR的VSMCs凋亡,可能机制是通过调节VSMCs的Bcl-2/Bax蛋白表达平衡。     

氧化型低密度脂蛋白诱导血管平滑肌细胞凋亡

AIM: To examine whether oxidized low density lipoproteins (ox-LDL) could induce apoptosis in rabbit aortic smooth muscle cells (VSMC). METHODS: Low density lipoproteins (n-LDL) were isolated from healthy human plasma by gradient ultracentrifugation and oxidized by CuSO4 10 mumol.L-1. VSMC were exposed to ox-LDL, n-LDL, or phosphate-buffer solution (PBS) as control. Morphological changes were observed under fluorescene microscope after Hoechst 33258 staining. Extracted DNA was electrophoresized on agarose gel. RESULTS: Incubation of VSMC with ox-LDL 300 mg.L-1, not n-LDL, for 24 h induced morphological apoptosis changes (chromatin condensation, nucleus fragmentation) and DNA fragmentation, which was furthered with the incubation time up to 48 h or at a concentration of 400 mg.L-1. Dextran sulfate, a scavenger receptor blocker and butylated hydroxytoluene (BHT), an antioxidant, exhibited no effect on DNA fragmentation. Lysophosphatidylcholine (LPC) at a concentration up to 125 mumol.L-1 (equivalent to ox-LDL 300 mg.L-1) did not elicit DNA fragmentation. CONCLUSION: Ox-LDL induced apoptosis in VSMC without involving oxygen free radicals and LPC.     

细胞内游离钙在辛伐他汀诱导大鼠血管平滑肌细胞凋亡中的作用

目的　研究 3 羟 3 甲戊二酰辅酶A (HMG CoA)还原酶抑制剂辛伐他汀诱导血管平滑肌细胞(VSMC)凋亡的机制。方法　以荧光染料Fura 2 /AM负载后荧光分光光度计法检测细胞内游离钙浓度 ,以DNA琼脂糖凝胶电泳、流式细胞仪PI/膜联蛋白 (an nexin)V染色及半胱天冬酶 3激活来检测细胞凋亡。结果　辛伐他汀 30 μmol·L- 1孵育VSMC后 ,细胞内游离钙浓度显著升高 ,6h时达对照的 3倍以上 (P <0 .0 1) ,维拉帕米 80 μmol·L- 1与辛伐他汀 30 μmol·L- 1共同孵育VSMC 6h后细胞内游离钙浓度为 (14 4± 34)nmol·L- 1(P <0 .0 1)。辛伐他汀可诱导细胞凋亡率增高、“DNA梯状”样改变及半胱天冬酶 3的激活 ,这些变化均可被维拉帕米所逆转。结论辛伐他汀通过使细胞外钙大量内流而诱导VSMC凋亡。     

雌激素对血管平滑肌细胞凋亡的影响

目的 :观察雌激素对血管平滑肌细胞 (SMC)凋亡的影响。方法 :以大鼠为对象 ,观察正常对照组、去卵巢组及去卵巢 +雌二醇治疗组大鼠血管平滑肌细胞凋亡的关系。结果 :雌二醇治疗组血管平滑肌细胞凋亡较去卵巢组相比明显减少(P>0 .0 5 ) ,与正常对照组比较差别无显著性意义 (P >0 .0 5 )。结论 :雌二醇对血管平滑肌细胞的凋亡有抑制作用 ,可能是其预防动脉粥样硬化的机制     

甲氨喋呤对血管平滑肌细胞增殖、迁移和凋亡的影响

目的　观察甲氨喋呤 (MTX)对体外培养的血管平滑肌细胞增殖、迁移和凋亡的影响。方法　体外培养兔胸主动脉血管平滑肌细胞 ,在培养基中加入不同浓度的MTX ,采用细胞计数及检测细胞周期的方法观察MTX对细胞增殖的影响 ,采用细胞刮片的方法观察MTX对细胞迁移的作用 ,采用检测DNA片断化的方法观察细胞凋亡现象。结果　①MTX在 2 5～ 10 0nmol·L-1的浓度范围内呈剂量依赖性地抑制VSMC增殖。② 2 5nmol·L-1及 5 0nmol·L-1MTX显著增加细胞周期中S期细胞的百分含量 ,减低G2 /M期细胞的百分含量 (P <0 0 5 ) ,10 0nmol·L-1MTX显著增加了G0 /G1期细胞的百分含量 (P <0 0 1)。③加入MTX的VSMC对血清刺激的迁移受到抑制。④ 10 0nmol·L-1及 2 0 0nmol·L-1的MTX作用于VSMC后 ,流式细胞仪检测亚二倍体的细胞数高于对照组 (P <0 0 1) ;DNA凝胶电泳可以见到梯形条带 ;TUNEL染色阳性细胞的百分数高于对照组 ,具有统计学差异 (P <0 0 1)。结论　甲氨喋呤能够抑制体外培养的血管平滑肌细胞增殖和迁移 ,并促进细胞凋亡。     

泛素-蛋白酶体抑制剂对血管平滑肌细胞凋亡的影响

血管平滑肌细胞(Vascular smooth muscle,VSMC)是构成血管壁的重要成分。在动脉粥样硬化(Atherosclerosis,AS)病变中,VSMC在病理状态下凋亡失平衡引起血管重塑,导致动脉粥样硬化的发生。目前研究发现,细胞凋亡在动脉粥样硬化形成的发病和治疗中具有重要意义,而泛素-蛋白酶体抑制剂(The ubiquitinproteasome inhibitor,UPI)能够促进VSM C凋亡进而影响动脉粥样硬化。本文对泛素-蛋白酶体抑制剂影响VSM C凋亡的机制进行了综述。     

镁离子对大鼠血管平滑肌细胞钙化的影响 , 镁离子对大鼠血管平滑肌细胞钙化的影响

目的 探讨不同浓度镁离子对大鼠血管平滑肌细胞(VSMCs)钙化的影响。方法 原代培养获取 VSMCs,进行形态学及免疫细胞鉴定,后将VSMCs随机分为阴性对照组、高磷组、镁干预组。阴性对照组采用含10%胎牛血清培养,高磷组采用高磷培养基培养,镁干预组在高磷培养基的基础上分别加入不同浓度氯化镁,使镁离子终浓度分别为1、2、3 mmol/L（镁干预组1~3）,刺激7 d后行钙化检测,测定钙含量及碱性磷酸酶（ALP）活性,并行反转录聚合酶链反应（RT-PCR）检测细胞内核心结合因子α1（Cbfα1）mRNA的表达。结果 高磷组和镁干预组VSMCs均有钙盐沉积,其钙含量均高于阴性对照组;镁干预组随镁离子浓度增大钙化结节逐渐缩小,除镁干预组1钙含量与高磷组无差异外,镁干预组2和镁干预组3均低于高磷组（均P＜0.05）。VSMCs ALP活性和Cbfα1 mRNA的表达除镁干预组3与阴性对照组无差异外,其余组均高于阴性对照组（P＜0.05）。镁干预组随镁离子浓度增大,ALP活性和Cbfα1 mRNA的表达水平均逐渐降低,且均低于高磷组（P＜0.05）。结论 镁离子可在一定程度上抑制高磷诱导的VSMCs钙化和成骨样转分化,其可能是通过降低VSMCs中Cbfα1的表达来实现的。     

葛根素对血管平滑肌细胞凋亡的影响

葛根素是中药葛根的有效成分 ,对心脑血管疾病具有广泛的药理作用[1] 。研究表明 ,经皮腔内冠状动脉成型术(ＰＴＣＡ)后最主要的并发症为再狭窄 ,其主要表现为血管平滑肌细胞 (ＶＳＭＣ)的增殖和迁移以及细胞外基质的增多 ,而ＶＳＭＣ和巨噬细胞的凋亡功能失调和 (或 )凋亡小体的清除不足是促进动脉粥样硬化发生、发展的重要因素[2 ] 。因而寻找能够促进动脉粥样硬化中ＶＳＭＣ凋亡的手段具有重要的临床意义。本实验利用体外细胞培养技术、流式细胞术、荧光显微镜观察了葛根素对ＶＳＭＣ凋亡的影响。1　材料和方法1.1　血管平滑肌原代细胞的…     

丹参素对血管平滑肌细胞钙化和凋亡的抑制作用

目的：探讨丹参素对血管平滑肌细胞（VSMCs）凋亡和钙化的影响。方法：β-磷酸甘油诱导培养的VSMCs发生钙化;通过细胞钙含量和碱性磷酸酶（ALP）活性测定,判断钙化程度;用Western blot方法检测细胞中骨形成蛋白BMP-2、凋亡相关蛋白Bax、Bcl-2和cleaved caspase 3的蛋白水平。结果：与正常组相比,β-磷酸甘油引起VSMCs中钙含量和ALP活性明显增加。丹参素显著抑制β-磷酸甘油引起的钙化VSMCs中的钙含量和ALP活性。Western blot结果显示β-磷酸甘油可引起VSMCs中BMP-2,bax和cleaved caspase 3的蛋白水平显著增高,Bcl-2蛋白水平明显降低;丹参素可明显改善钙化的VSMCs中上述蛋白的变化。结论：丹参素可以抑制VSMCs发生钙化和凋亡,此效应可能与抑制BMP-2、bax和cleaved caspase 3的蛋白水平,上调Bcl-2蛋白水平有关。     

雷公藤甲素对兔血管平滑肌细胞增生和凋亡的影响

目的：研究雷公藤甲素（TP）是否具有抑制血管平滑肌细胞（VSMCs）增殖并诱导其发生凋亡的作用,为临床开发新型药物洗脱支架提供实验依据。方法：体外主动脉SMCs培养和流式细胞仪检测,DNA凝胶电泳。结果：TP组与空白对照组及地塞米松组相比,凋亡率有显著提高;TP干预组凝胶电泳谱型呈凋亡特征性梯状条带。结论：TP可抑制指数生长期SMCs增殖并诱导其凋亡。     

泛素-蛋白酶体抑制剂对血管平滑肌细胞凋亡和动脉粥样硬化的影响

泛素-蛋白酶体系统(Ubiquitin proteasome system,UPS)是真核细胞内蛋白质降解的核心途径,对细胞周期、炎症反应、细胞凋亡的调节起十分重要的作用。血管平滑肌细胞(Vascular smooth muscle cells,VSM C)作为血管壁的重要细胞成分,其增殖与凋亡的失平衡是决定动脉粥样硬化发生、发展的关键环节。在VSM C中,细胞凋亡与UPS活性密切相关,且UPS对动脉粥样硬化各个阶段有显著的调节作用。泛素-蛋白酶体抑制剂(Ubiquitin-proteasome inhibitors,UPI)通过抑制凋亡相关蛋白的降解,从而调控VSMC的凋亡,影响动脉粥样硬化形成的各个阶段。本文综述了UPI对VSMC凋亡的影响及其在动脉粥样硬化各阶段的调节作用。     

他汀类药物与血管平滑肌细胞凋亡

血管平滑肌细胞（VSMC）的异常增殖和迁移在粥样斑块形成和冠状动脉介入治疗（PCI）后再狭窄中起非常重要的作用。他汀类药物不仅是一种有效的调脂药，同时还有多种调脂以外的作用。如他汀类药物可以抑制VSMC的增殖和迁移，并诱导其凋亡。临近病变部位的中层VSMC的凋亡可能造成斑块纤维帽容易破裂，进而引起斑块不稳定和临床事件。但研究证实他汀类药物有稳定斑块的作用，且新生内膜VSMC对他汀类药物诱导的凋亡作用比普通的血管中层VSMC更敏感。因此，他汀类药物的促新生内膜VSMC凋亡作用可能对预防PCI术后再狭窄起有益作用。具体作用机制以及临床上如何合理发挥此类作用尚待进一步研究。     

Magnolol induces apoptosis in vascular smooth muscle

Magnolol, an active component extracted from Magnolia officinalis, has various pharmacological effects, including potent antioxidant activity. In the present study, we investigated the effect of magnolol on apoptosis in rat vascular smooth muscle cells (VSMCs), using terminal-deoxynucleotidyl-transferase-mediated deoxyuridine triphosphate nick end labelling (TUNEL) and flow cytometric analysis. Magnolol (5–20 µM) concentration-dependently induced significant VSMC apoptosis, this effect being blocked by the caspase inhibitor benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone (z-VAD-fmk, 50 µM). To study the molecular mechanism, the mitochondrial death pathway was examined. Magnolol increased caspase-3 and caspase-9 activities significantly and reduced the mitochondrial potential (_m). The levels of B-cell leukaemia/lymphoma-2 (Bcl-2), but not those of Bcl-2-associated X protein (Bax) or Bcl-x_L, were down-regulated concentration dependently by magnolol. In an animal model, balloon angioplasty-induced neointima formation was inhibited significantly by magnolol and Bcl-2 protein levels were reduced. Taken together, these results show that magnolol induces apoptosis in VSMCs via the mitochondrial death pathway. This effect is mediated through down-regulation of Bcl-2 protein levels, both in vivo and in vitro. Magnolol thus shows potential as a novel therapeutic agent for the treatment of atherosclerosis and re-stenosis.     

卡维地洛对血管平滑肌细胞DNA合成的影响

目的 :探讨卡维地洛对血管平滑肌细胞(VSMC)增殖的影响及其可能机制。方法 :通过贴壁细胞培养法建立豚鼠主动脉血管平滑肌细胞模型 ,应用 [3 H]TDR掺入试验研究卡维地洛对反应性氧族 (reactiveoxygenspecies ,ROS)、血管紧张肽Ⅱ(angiotensinⅡ ,AngⅡ )及胎牛血清 (fetalcalfserum ,FCS)诱导的血管平滑肌细胞增殖的影响。结果 :卡维地洛呈剂量依赖性地抑制ROS ,AngⅡ及FCS诱导的血管平滑肌细胞DNA合成 ,最大抑制率分别为 (48± 15 ) % ,(42± 7) %和 (44± 14) %。结论 :卡维地洛对ROS及AngⅡ诱导的血管平滑肌细胞DNA合成呈剂量相关性的抑制作用 ,提示卡维地洛可能通过抗氧化的途径抑制血管平滑肌细胞增殖     

半胱氨酸对人血管平滑肌细胞增殖和凋亡的影响

目的 观察半胱氨酸(Cys)对人血管平滑肌细胞(VSMCs)增殖和凋亡的影响.方法 采用组织贴块法体外培养人VSMCs,用不同浓度的Cys培养液孵育细胞24h,用MTT法检测VSMCs增殖,流式细胞术检测VSMCs凋亡.RT-PCR法检测bax mRNA的表达.结果 体外培养的人VSMCs在终浓度为100、200、500和10001μmol/L Cys的培养液中孵育24h后的吸光度(A)值均高于对照组(P<0.05),表明Cys可诱导人VSMCs增殖;但同时.VSMCs凋亡细胞数明显高于对照组(P<0.05),bax的表达增强,表明Cys亦诱导了人VSMCs凋亡.结论 浓度较高时半胱氨酸可同时诱导VSMCs增殖和凋亡.     

Concentration-dependent differential effects of udenafil on viability,proliferation, and apoptosis in vascular endothelial and smooth muscle cells

Objectives:

Local strategies directed against vascular smooth muscle cell (VSMC) proliferation, such as drug-eluting stents (DES), reduce the occurrence of restenosis. However, these approaches may also inhibit vascular endothelial cell (VEC) proliferation and impair reendothelialization, and hence, increase susceptibility to late thrombosis. In this study we examined the differential effects of various concentrations of the type 5 phosphodiesterase (PDE-5) inhibitor, udenafil, on viability, proliferation, and apoptosis of VEC and VSMC, in order to identify the optimal concentration of udenafil that minimizes inhibition of VEC survival and growth, and maximizes inhibition of VSMC survival and growth.

Materials and Methods:

VEC from human umbilical veins and VSMC from human aorta were exposed to various concentrations of udenafil (1, 10, and 100 μmol/l and 1 mmol/l) for 24 h, and its effects on cell viability, proliferation, and apoptosis were studied using 5-bromo-2’- deoxyuridine (BrdU), methylthiazoletetrazolium (MTT) assay, trypan blue dye exclusion, and flow cytometry.

Results:

Udenafil inhibited the survival and growth of VEC and VSMC in a concentration-dependent manner over a range of concentrations. At 100 μmol/l, udenafil, inhibited VEC proliferation significantly less than VSMC proliferation (P < 0.05), and could significantly induce VEC apoptosis less than VSMC apoptosis (P < 0.05).

Conclusions:

Udenafil has a differential effect on survival and growth in VEC and VSMC. The maximal differential effect, with minimal inhibition of VEC and maximal inhibition of VSMC, occurs at 100 μmol/l. This characteristic suggests that udenafil is a promising agent for use in DES.KEY WORDS: Drug-eluting stent, proliferation, udenafil