降钙素基因相关肽对大鼠血管平滑肌细胞CDK2和Cyclin E的影响

目的:研究降钙素基因相关肽(CGRP)对大鼠血管平滑肌细胞中细胞周期蛋白依赖性激酶2(cyclin-dependent kinase 2,CDK2)和细胞周期蛋白E(Cyclin E)的影响,为阐明CGRP抑制血管平滑肌细胞增殖的细胞周期机制提供实验依据。方法:培养大鼠胸主动脉血管平滑肌细胞,分别用CGRP或/和10%FBS处理细胞。噻唑蓝比色法(MTT)观察CGRP对10%FBS诱导大鼠血管平滑肌细胞增殖的影响;流式细胞术分析细胞周期;Western blot检测CDK2和Cyclin E的表达。结果:CGRP能抑制10%FBS诱导的血管平滑肌细胞增殖,升高G0/G1期细胞百分比,降低S+G2+M期细胞百分比,抑制细胞内CDK2和Cyclin E表达。结论:CGRP能通过阻滞细胞周期由G0/G1期进入S期而抑制血管平滑肌细胞增殖,其作用机制可能与降低CDK2和Cyclin E表达有关。     

Endothelin—1 promoted proliferation of vascular smooth muscle cell through pathway of extracellular signal—regulated kinase and cyclin D1

目的:探讨内皮素-1是否通过细胞周期蛋白质D1与细胞外调节蛋白激酶通路促进人脐动脉平滑肌细胞增殖。方法:采用MTT法观察ET-1和PD98059对人脐动脉平滑肌细胞生长的作用;[~3H]TdR法观察对细胞DNA合成的作用;流式细胞仪法观察对细胞增殖周期的影响;蛋白质印迹法观察对细胞外调节蛋白激酶和细胞周期蛋白质D1表达的影响。结果:首先,同没有ET-1组和PD98059组比较,ET-1促进平滑肌细胞增殖(P<0.05)。PD98059抑制ET-1诱导的血管平滑肌细胞增殖。第二,与没有ET-1组比较,ET-1促进平滑肌细胞DNA合成(P<0.05)。第三,ET-1促进平滑肌细胞增殖周期从G_0/G_1期向S期的转变,与没有ET-1组比较,G_0/G_1期细胞百分比明显减少,S期细胞百分比明显增加(P<0.05)。第四,ET-1增加细胞外信号调节性激酶的磷酸化水平和细胞周期蛋白质D1的蛋白表达,ERK的抑制剂可以抑制细胞外信号调节性激酶的磷酸化水平和细胞周期蛋白质D1的蛋白表达,与没有ET-1组比较,磷酸化-ERK和细胞周期蛋白质D1表达明显增强,对非磷酸化ERK表达没有影响。结论:内皮素-1可以通过细胞周期调节素D1与细胞外信号调节性激酶通路促进平滑肌细胞增殖。     

Roscovitine对TNF-α诱导的大鼠血管平滑肌细胞增殖及细胞周期的影响

目的观察Roscovitine对TNF-α诱导的大鼠血管平滑肌细胞(VSMC)增殖及细胞周期的影响。方法组织贴块法培养大鼠VSMC细胞,采用TNF-α诱导其增殖,加入不同浓度的Roscovitine预处理15 h,将细胞分为:对照组、TNF-α组、Roscovitine 5、10、15、30μmol·L~(-1)组。MTT比色法检测细胞增殖活性;Western blot检测增殖细胞核抗原(PCNA);流式细胞仪检测细胞周期;荧光定量RT-PCR及Western blot检测细胞周期蛋白(Cyclin A、Cyclin B、Cyclin D、Cyclin E)、细胞周期蛋白依赖激酶(CDK4、CDK5)、细胞周期抑制蛋白(p53、p21、p27)的表达。结果 Roscovitine能抑制VSMC增殖;抑制细胞周期从G_0/G_1期向S期转化。与TNF-α组比较,Roscovitine 5、10、15、30μmol·L~(-1)组能降低细胞周期蛋白Cyclin A、Cyclin B、Cyclin D、Cyclin E蛋白表达,降低细胞周期蛋白依赖激酶CDK4、CDK5蛋白表达,升高细胞周期抑制蛋白p53、p21、p27蛋白表达(P<0.05)。结论 Roscovitine可抑制大鼠VSMC细胞周期进程及增殖活性。     

中介素对缺氧/复氧大鼠肾小管上皮细胞增殖作用及细胞周期的影响及其机制

目的探讨中介素(intermedin,IMD)对大鼠近端肾小管上皮细胞NRK-52E缺氧/复氧(H/R)后细胞增殖、细胞周期的影响。方法 NRK-52E细胞随机分为对照组,模型组:缺氧/复氧组(H/R)、H/R+空质粒组、H/R+IMD质粒组。MTT法检测细胞增殖,比色法检测培养基上清LDH含量,流式细胞术检测细胞周期,Real time-PCR法和Western blot法检测cyclin D1、CDK、p57 mRNA及蛋白表达,间接免疫荧光染色检测cyclin D1亚细胞定位。结果 1与对照组相比,H/R组培养基中LDH含量升高了106%,同时细胞存活率明显下降,与H/R组比较,H/R+IMD组培养基中LDH含量下降了33.85%(P<0.01),而细胞存活率增高(79.15%±1.42%vs 61.22%±1.63%,P<0.05),2细胞周期结果显示,与对照组相比,H/R组细胞G0/G1期比例增加,S期细胞比例降低(P<0.05);与H/R组比较,H/R+IMD组G0/G1期细胞比例明显降低,而S及G2期细胞比例增加(P<0.05)。3H/R可增加cyclin D1、CDK4及p57的表达也增加(与对照组比较,P<0.05);而IMD可进一步上调cyclin D1、CDK4的表达,同时下调p57的表达,与对照组及H/R组相比差异具有显著性(P<0.05)。4免疫荧光检测结果可见,cyclin D1呈红色荧光,在NRK-52E细胞内主要表达在细胞核中。结论 IMD可以上调cyclin D1、CDK4蛋白表达,下调p57的表达,促进细胞周期进展,从而加速肾组织IRI后细胞增殖和修复。     

黄芪抑制血管平滑肌细胞增殖及其作用机制

目的 观察黄芪(AS)对血管平滑肌细胞(VSMC)增殖的抑制作用,了解黄芪是否通过刺激VSMC产生一氧化氮(nitric oxide,NO),使细胞周期停滞于G0／G1期,从而抑制平滑肌细胞增殖。方法 [3H]-胸腺嘧啶核苷酸([3H]-TdR)掺入测定VSMCDNA合成,流式细胞仪检测细胞周期情况,硝酸还原酶法测定细胞培养上清中NO水平。结果 黄芪以剂量依赖关系抑制血清诱导的VSMC[3H]-胸腺嘧啶核苷酸掺入,使G0／G1期细胞比例明显增多,S期细胞比例显著减少,黄芪刺激VSMC后,细胞培养上清中NO水平呈剂量依赖上升。结论黄芪能抑制VSMC增殖,使细胞周期停滞于G0／G1期,这一过程可能与黄芪刺激VSMC产生NO有关。     

二氢青蒿素对体外培养胃癌细胞株BGC-823周期蛋白D1 P16蛋白表达的影响

目的探讨二氢青蒿素(DHA)对人胃癌细胞BGC-823增殖的抑制作用及周期蛋白D1、P16蛋白表达的影响。方法以25～100μmol/L DHA干预人胃癌细胞株BGC-823细胞后通过四甲基偶氮唑盐(MTT)比色法测定细胞增殖率,吖啶橙-溴化乙定(AO-EB)染色观察细胞凋亡情况、流式细胞仪检测细胞凋亡周期、蛋白质印迹法检测细胞中周期蛋白D1、P16蛋白表达情况。结果 DHA对人胃癌细胞具有时间、浓度依赖性抑制作用;且浓度依赖性阻滞细胞周期,使G0/G1期细胞增多,S期细胞减少(P<0.05)。DHA浓度依赖性下调cyclin D1蛋白,上调p16蛋白的表达(P<0.05)。结论 DHA通过下调cyclin D1蛋白,上调p16蛋白的表达,调节细胞周期调控通路,阻滞细胞于G0/G1期,有效抑制人胃癌细胞的增殖。     

人参总皂苷对PDGF-BB所致血管平滑肌细胞增殖周期的影响

目的研究人参总皂苷(totel ginsenosides,TG)对血小板源性生长因子BB型(PDGF-BB)所致血管平滑肌细胞(VSMC)增殖周期的影响并探讨其可能的机制。方法组织块贴壁法培养SD大鼠胸主动脉平滑肌细胞,MTT比色法观察TG(10、30、100mg·L-1)对PDGF-BB(25μg·L-1)所致的VSMC增殖的影响;流式细胞仪分析细胞增殖周期;Re-al-timeRT-PCR检测VSMC中内皮型一氧化氮合酶(eNOS)、周期蛋白依赖性蛋白激酶抑制因子P27(KIP1)、原癌基因c-fos、周期蛋白D1(CyclinD1)mRNA的表达。结果在正常细胞中加入TG100mg·L-1不影响细胞的吸光度值及G0/G1期、G2/M期、S期细胞比例(P>0.05);PDGF-BB可明显升高吸光度值(P<0.01),增加S期细胞比例而降低G0/G1期细胞比例(P<0.01),并明显增加c-fos、CyclinD1 mRNA的表达,下调eNOS和P27(KIP1)的表达(P<0.01)。TG低、中、高浓度均明显抑制PDGF-BB诱导的吸光度值升高(P<0.01),降低S期细胞比例而升高G0/G1期细胞比例,明显下调PDGF-BB所致的c-fos及CyclinD1 mRNA高表达(P<0.01),并使eNOS mRNA表达升高(P<0.05),但对P27(KIP1)的表达无明显影响(P>0.05)。结论 TG通过阻止VSMC由G0/G1期进入S期而抑制PDGF-BB所致的增殖,其作用机制可能与其提高eNOSmRNA表达、降低c-fos和CyclinD1 mRNA高表达有关。     

Apelin-13促大鼠血管平滑肌细胞增殖的PKC-ERK1/2信号通路研究

目的研究G蛋白偶联受体APJ(血管紧张素受体样受体或称血管紧张素受体AT1相关的受体蛋白,putativere-ceptor protein related to the angiotensin receptor AT1)的内源性配体apelin-13通过PKC-ERK1/2-Cyclins信号通路促进大鼠血管平滑肌细胞(vascular smooth muscle cells,VSMCs)增殖的影响。方法培养SD大鼠胸主动脉VSMCs,Western blot检测p-ERK1/2、ERK1/2、细胞周期蛋白CyclinD1和CyclinE的表达,四噻唑蓝比色法观察PKC阻断剂GF109203X对apelin-13促大鼠VSMCs增殖的影响。结果Apelin-13剂量依赖性和时间依赖性地促进大鼠VSMCsp-ERK1/2表达增加,对ERK1/2表达没有明显影响,GF109203X可明显抑制apelin-13诱导的细胞增殖及p-ERK1/2、CyclinD1和CyclinE的表达。结论Apelin-13促进大鼠VSMCs增殖可能与ape-lin-APJ-PKC-ERK1/2-Cyclins信号通路有关。     

shRNA介导的Iduna沉默对肺癌A549细胞系细胞周期及其相关蛋白表达的影响

目的利用shRNA沉默E3泛素连接酶Iduna基因,观察Iduna对非小细胞肺癌细胞系A549细胞周期及其相关蛋白表达的影响。方法采用反转录聚合酶链反应(RT-PCR)和蛋白印迹法筛选Iduna高表达细胞系。构建shRNA-Iduna真核表达载体,瞬时转染A549细胞,蛋白印迹法检测转染效率。流式细胞仪检测细胞周期变化。蛋白印迹法检测细胞周期相关蛋白的表达。结果蛋白印迹法筛选Iduna高表达细胞系显示A549和SPC细胞中Iduna mRNA和蛋白水平高于其他细胞系。shRNA-Iduna转染A549细胞系后,流式细胞仪检测细胞周期显示干扰组G0/G1期比例增加,S期比例相对减少(P<0.05)。蛋白印迹法检测与细胞周期相关的G1/S期调控蛋白[细胞周期蛋白(cyclin)A、cyclin D1、cyclin E、CDK2、CDK4、CDK6、P21、P27、P53等]的表达情况,结果显示干扰组cyclin D1、cyclin E和CDK4蛋白表达减少(P<0.05)。结论 Iduna可能通过调控cyclin D1、cyclin E和CDK4蛋白的表达,使细胞阻滞于G0/G1期,从而调节肺癌细胞周期进程。     

姜黄素烟酸酯对血管平滑肌细胞增殖及ERK1/2信号通路的影响

目的探讨姜黄素烟酸酯(curcumin trinicotinate,Cur Tn)对血管平滑肌细胞(vascular smooth muscle cell,VSMC)增殖的影响及其可能机制。方法体外培养VSMC,体积分数为0.1的FBS刺激VSMC生长。MTT法观察CurT n对VSMC活力的影响;流式细胞术分析细胞周期;Western blot检测PCNA、p-ERK1/2、CyclinD 1蛋白的表达。结果 CurT n抑制VSMC增殖并呈现一定量效、时效关系,并且使G1期的细胞比例增加,S期细胞比例下降,PCNA蛋白表达下调。同时发现CurT n能明显抑制p-ERK1/2、CyclinD 1蛋白表达。结论 CurT n能明显抑制VSMC增殖,其作用机制可能与p-ERK1/2、CyclinD 1蛋白表达下调有关。     

Growth-inhibitory effect of cyclic GMP- and cyclic AMP-dependent vasodilators on rat vascular smooth muscle cells: effect on cell cycle and cyclin expression

1. The possibility that the antiproliferative effect of cyclic GMP- and cyclic AMP-dependent vasodilators involves an impaired progression of vascular smooth muscle cells (VSMC) through the cell cycle and expression of cyclins, which in association with the cyclin-dependent kinases control the transition between the distinct phases of the cell cycle, was examined. 2. FCS (10%) stimulated the transition of quiescent VSMC from the G0/G1 to the S phase (maximum within 18-24 h and then to the G2/M phase (maximum within 22-28 h). Sodium nitroprusside and 8-Br-cyclic GMP, as well as forskolin and 8-Br-cyclic AMP markedly reduced the percentage of cells in the S phase after FCS stimulation. 3. FCS stimulated the low basal protein expression of cyclin D1 (maximum within 8-24 h) and E (maximum within 8-38 h) and of cyclin A (maximum within 14-30 h). The stimulatory effect of FCS on cyclin D1 and A expression was inhibited, but that of cyclin E was only minimally affected by the vasodilators. 4. FCS increased the low basal level of cyclin D1 mRNA after a lag phase of 2 h and that of cyclin A after 12 h. The vasodilators significantly reduced the FCS-stimulated expression of cyclin D1 and A mRNA. 5. These findings indicate that cyclic GMP- and cyclic AMP-dependent vasodilators inhibit the proliferation of VSMC by preventing the progression of the cell cycle from the G0/G1 into the S phase, an effect which can be attributed to the impaired expression of cyclin D1 and A.     

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。     

Apamin inhibits PDGF-BB-induced vascular smooth muscle cell proliferation and migration through suppressions of activated Akt and Erk signaling pathway

The increased proliferation and migration of vascular smooth muscle cells (VSMC) are key process in the development of atherosclerosis lesions. Platelet-derived growth factor (PDGF) initiates a multitude of biological effects that contribute to VSMC proliferation and migration. Apamin, a component of bee venom, has been known to block the Ca^2 +-activated K⁺ channels. However, the effects of apamin in the regulation PDGF-BB-induced VSMC proliferation and migration has not been identified. In this study, we investigate the inhibitory effect of apamin on PDGF-BB-induced VSMC proliferation and migration. Apamin suppressed the PDGF-BB-induced VSMC proliferation and migration with no apparent cytotoxic effect. In accordance with these findings, apamin induced the arrest of cell cycle progression at G0/G1 phase. Apamin also decreased the expressions of G0/G1 specific regulatory proteins including proliferating cell nuclear antigen (PCNA), cyclin D1, cyclin-dependent kinases (CDK) 4, cyclin E and CDK2, as well as increased the expression of p21^Cip1 in PDGF-BB-induced VSMC. Moreover, apamin inhibited PDGF-BB-induced phosphorylation of Akt and Erk1/2. These results suggest that apamin plays an important role in prevention of vascular proliferation and migration through the G0/G1 cell cycle arrest by PDGF signaling pathway. Thus, apamin may be a promising candidate for the therapy of atherosclerosis.     

Artemisinin inhibits tumour necrosis factor‐α‐induced vascular smooth muscle cell proliferation in vitro and attenuates balloon injury‐induced neointima formation in rats

The aim of this study was to evaluate the effect of artemisinin (ART) on rat vascular smooth muscle cell (VSMC) proliferation induced by tumour necrosis factor (TNF)‐α, cell cycle arrest, and apoptosis, and its effect on neointima formation after balloon injury of rat carotid artery. Primary rat VSMC were identified by immunofluorescence assay. The proliferation of VSMC induced by TNF‐α was significantly inhibited by ART treatment in a dose‐dependent manner. Treatment with 100‐μM ART significantly reduced the expression of proliferating cell nuclear antigen. In contrast, the same treatment arrested the cell cycle in G0/G1 phase. Western blot analysis showed that the cell cycle‐related proteins cyclin D1, cyclin E, cyclin‐dependent kinase 2, and cyclin‐dependent kinase 4 were downregulated by ART in TNF‐α‐stimulated VSMC. For apoptosis induced by ART, cleaved caspase‐3/‐9 was detected, and the pro‐apoptotic protein Bcl‐2‐associated X protein was upregulated while the anti‐apoptotic protein Bcl‐2 was downregulated. The results suggest that ART can effectively inhibit the proliferation of VSMC induced by TNF‐α through the apoptotic induction pathway and cell cycle arrest. Also, balloon injury indicated that ART significantly inhibited neointima formation in the rat carotid arteries.     

钩藤碱和异钩藤碱抑制血管紧张素Ⅱ诱导血管平滑肌细胞增殖及相关机制

目的探讨钩藤碱和异钩藤碱对血管紧张素Ⅱ诱导的血管平滑肌细胞增殖的抑制效应及相关机制。方法建立血管紧张素Ⅱ诱导血管平滑肌细胞增殖模型,通过四甲基偶氮唑盐比色法、流式细胞术和逆转录聚合酶链反应观察钩藤碱和异钩藤碱对其增殖活性、细胞周期、细胞膜AT1R蛋白表达、信号转导通路NF-κB和Stat3蛋白表达、原癌基因c-Myc和c-Fos蛋白表达与mRNA转录的影响。结果血管紧张素Ⅱ明显刺激血管平滑肌细胞增殖,钩藤碱和异钩藤碱呈剂量依赖性抑制血管紧张素Ⅱ诱导的血管平滑肌细胞增殖;在钩藤碱和异钩藤碱干预下,血管平滑肌细胞处于G0/G1期的细胞数明显增多,S期的细胞数明显减少,c-Myc、c-Fos、AT1R、NF-κB、Stat3的蛋白表达以及c-MycmRNA和c-FosmRNA转录也明显降低。结论钩藤碱和异钩藤碱对血管紧张素Ⅱ诱导血管平滑肌细胞增殖有明显抑制效应,其机制与阻滞血管平滑肌细胞G0/G1期向S期转化以及下调AT1R、NF-κB、Stat3、c-Myc、c-Fos蛋白的表达以及c-MycmR-NA和c-FosmRNA转录有关。     

2,3,4',5-Tetrahydroxystilbene-2-O-β-d-glucoside inhibits platelet-derived growth factor-induced proliferation of vascular smooth muscle cells by regulating the cell cycle

1. 2,3,4',5-Tetrahydroxystilbene-2-O-β-d-glucoside (TSG) has been shown to have an anti-atherosclerotic effect. Vascular smooth muscle cell (VSMC) proliferation contributes to the pathobiology of atherosclerosis. The aim of the present study was to investigate the effects of TSG on platelet-derived growth factor (PDGF)-BB-induced VSMC proliferation and to explore the molecular mechanisms underlying the effects. 2. Cultured rat VSMC were pretreated with TSG (l-50 μmol/L) for 1 h, followed by exposure to PDGF-BB (10 ng/mL) for 24 h, after which cell proliferation and cell cycle stages were examined. The expression of protein cell cycle regulators, including retinoblastoma (Rb), cyclin D1/E, cyclin-dependent kinase (CDK) 2/4, CDK inhibitors p21 and p27 and proliferative cell nuclear antigen (PCNA), was examined. Activation of extracellular signal-regulated kinase (ERK) 1/2 was evaluated to elucidate the possible upstream mechanism by which TSG affects cell cycle regulators. 3. The results showed that TSG dose-dependently inhibited PDGF-BB-induced VSMC proliferation, possibly by blocking the progression of the cell cycle from the G(1) to S phase. In addition, TSG significantly inhibited PDGF-BB-induced phosphorylation of Rb and the expression of cyclin D1, CDK4, cyclin E, CDK2 and PCNA. In addition, TSG suppressed PDGF-BB-induced downregulation of p27 and upregulation of p21, as well as PDGF-BB-induced activation of ERK1/2. 4. Together, the findings of the present study provide the first evidence that TSG can inhibit PDGF-BB-stimulated VSMC proliferation via cell cycle arrest in association with modulation of the expression of cell cycle regulators, which may be mediated, at least in part, by suppression of ERK1/2 activation.     

牛磺酸对心肌成纤维细胞细胞周期的影响及其机制的研究

目的研究牛磺酸(taurine,Tau)对血管紧张素Ⅱ(an-giotensinⅡ,AngⅡ)诱导的新生大鼠心肌成纤维细胞(cardiacfibroblast,CFb)增殖的抑制作用,并初步探讨其作用机制。方法用AngⅡ诱导新生大鼠CFb增殖,建立心肌纤维化模型,采用四甲基偶氮唑盐(MTT)法检测细胞增殖;羟脯氨酸测定检测胶原含量;流式细胞仪检测细胞周期及细胞周期蛋白依赖性激酶抑制物p27的变化;免疫细胞化学法测定细胞周期调控蛋白D(cyclin D)及p27蛋白的含量。结果Tau(40、80、160mmol.L-1)可明显抑制AngⅡ诱导的CFb增殖与胶原合成,同AngⅡ组比较差异有显著性(P<0.05或P<0.01),且呈现剂量依赖性。流式细胞仪检测表明Tau在80、160mmol.L-1可促进p27的蛋白表达;细胞G0/G1期百分率随Tau浓度增加而增加,S期细胞百分率随Tau浓度增加而减少,与AngⅡ组相比差异有显著性(P<0.05或P<0.01)。免疫细胞化学染色结合图像分析系统的分析结果也表明Tau可增加p27的蛋白表达,与AngⅡ组相比差异具有统计学意义(P<0.01)。结论牛磺酸通过促进p27的表达,使细胞周期阻滞于G0/G1期,而抑制CFb增殖和胶原含量的增加。     

Hemin inhibits hypertensive rat vascular smooth muscle cell proliferation through regulation of cyclin D and p21

We tested the hypothesis that HO-1 (heme oxygenase-1) activity varied between vascular smooth muscle cells (VSMC) in spontaneously hypertensive (SHR) and normotensive Wistar-Kyoto (WKY) rats. HO-1 levels were measured under baseline and hemin-stimulated conditions and cell proliferation was monitored. Basal HO-1 levels in untreated cells were lower in SHR compared to WKY rats. Treatment with hemin increased HO-1 mRNA and protein levels in the cells obtained from WKY rats compared to that of SHR rats. However, hemin-treatment showed a greater inhibitory effect on VSMC proliferation in SHR rats than in WKY rats. Tin protoporphyrin IX (SnPPIX) showed a greater reversal of the anti-proliferative effect of hemin on cells from SHR rats than WKY. Similarly, VSMC proliferation from SHR was significantly inhibited in VSMC transfected with the HO-1 gene. These inhibitory effects were associated with cell cycle arrest in the G1 phase. The level of cyclin D, and cyclin dependent kinase inhibitor p21 was higher in SHR cells progressing through the G1 phase. Treatment of the cells with hemin down-regulated the expression of cyclin D and up-regulated that of p21. These results indicate that hemin, an HO-1 inducer, may play a more critical role in VSMC proliferation in SHR than WKY.     

Ferulic acid inhibits vascular smooth muscle cell proliferation induced by angiotensin II

The aim of this study was to determine the effects of ferulic acid on the proliferation and molecular mechanism in cultured vascular smooth muscle cell (VSMC) induced by angiotensin II. It was shown that ferulic acid significantly inhibited angiotensin II-induced VSMC proliferation in a dose-dependent manner. Western blotting analyses suggest that the antiproliferative effect of ferulic acid was involved in the mitogen-activated protein kinases (MAPKs) pathway. While no effect on p38, ferulic acid markedly inactivated the extracellular signal-regulated kinases (ERK1/2) and c-Jun N-terminal kinases (JNK), indicating that the inhibition of ferulic acid on VSMC proliferation was associated with ERK1/2 and JNK rather than p38 pathway. On the expression of cell cycle regulatory proteins, ferulic acid elevated the protein content of p21(waf1/cip1), decreased expression of cyclin D1 and inhibited phosphorylation of retinoblastoma protein, suggesting that ferulic acid inhibited VSMC proliferation by regulating the cell progression from G1 to S phase. The inactivation of MAPKs and modulation of cell cycle proteins of ferulic acid may be of importance in preventing cardiovascular disease.