青蒿素对血管平滑肌细胞增殖的影响

目的 :观察青蒿素 (artemisinin ,Art)对体外培养大鼠主动脉平滑肌细胞 (VSMC)的增殖、DNA合成及细胞周期的影响 ,探讨作用机制。方法 :体外培养大鼠主动脉VSMC ,分为不同浓度的Art组及对照组。观察细胞生长曲线 ;四甲基偶氮唑盐微量酶反应 (MTT)法检测细胞活性 ;3H 胸腺嘧啶脱氧核苷(3H- TdR)掺入法观察其对DNA合成的影响 ;通过HE染色、DNA梯带检测和流式细胞术观察细胞的凋亡并测定细胞周期。结果 :与对照组相比 ,各浓度Art组VSMC计数不同程度减少 ,3H- TdR掺入率降低 ,细胞增殖受抑制 ,VSMC凋亡增加 ,并呈浓度依赖性 ;Art诱导细胞凋亡 ;使细胞周期阻滞于G0 / G1 期。结论 :Art对体外培养VSMC的增殖有抑制作用 ,可能通过抑制细胞DNA合成 ,诱导细胞凋亡及干扰细胞周期等途径发挥作用     

三氧化二砷对培养的兔血管平滑肌细胞增殖和迁移的影响

目的研究中药三氧化二砷(As2O3)对兔血管平滑肌细胞(VSMC)增殖及迁移的影响。方法采用四氮唑蓝(MTT)还原反应和3H-TdR掺入率观察该药对细胞增殖和DNA合成的影响;相差显微镜下测量细胞迁移。结果As2O3对VSMC增殖具有抑制作用,作用呈剂量及时间的依赖性;随着As2O3浓度增加体外培养的VSMC迁移距离缩短。结论适宜浓度的As2O3可明显抑制体外培养的兔VSMC的增殖、迁移。     

西拉普利对血小板源生长因子诱导的血管平滑肌细胞增殖的影响

目的 为探讨西拉普利预防再狭窄及动脉粥样硬化的可能性，研究了西拉普利对血小板源生长因子（PDGF）诱导的血管平滑细胞（VSMC）增殖的影响。方法 以培养的大鼠VSMG为模型、应用^H－TdR掺入试验观察VSMC增殖情况。结果 PDGF能明显促进VSMC DNA合成，大剂量西拉普利能抑制PDGF诱导的细胞DNA合成，小剂量西拉普利增加细胞DNA合成。结论 大剂量西拉普利能明显抑制VSMC增殖、对防治再狭窄及动脉粥样硬化可能有效。     

CD40-CD40配体对大鼠主动脉平滑肌细胞增殖及迁移影响

目的:观察CD40-CD40配体(CD40-CD40L)相互作用对体外培养的大鼠主动脉平滑肌细胞(VSMC)增殖及迁移的影响。方法:应用组织贴块法进行SD大鼠主动脉VSMC原代培养,以3H-胸腺嘧啶脱氧核苷(3H-TdR)、3H-亮氨酸(3H-Leu)掺入法分别测定VSMC增殖,VSMC的迁移采用琼脂糖凝胶刮取法,用倒置显微镜观察。结果:CD40-CD40L相互作用能明显促进VSMC3H-TdR、3H-Leu向细胞的掺入率,两者具有时间、剂量依赖性,CD40-CD40L相互作用随CD40L浓度的增加及刺激时间延长(30h内),能明显增加VSMC迁移率,抗-CD40单克隆抗体能明显抑制上述效应。结论:CD40-CD40L相互作用能明显促进主动脉VSMC增殖和迁移。     

槲皮素及异鼠李素对人血管平滑肌细胞增殖的抑制作用

目的观察槲皮素(QUE)及异鼠李素(ISOR)对培养人血管平滑肌细胞增殖的影响。方法本实验利用培养的人主动脉平滑肌细胞(VSMC),采用细胞计数、3H-胸腺嘧啶核苷酸(3H-TdR)掺入法,观察QUE、ISOR、去甲肾上腺素(NE)对VSMC增殖、DNA合成的影响,以及QUE、ISOR、酚托拉明(Ph)对NE促VSMC增殖、DNA合成的的影响。结果①QUE有明显抑制VSMC增殖、DNA合成的作用,而ISOR作用较弱。在所观察的1～200(滋mol/L的浓度范围内,QUE和ISOR均在200滋mol/L浓度发挥了最大的抑制作用,其抑制作用有剂量依赖关系。②NE有促进VSMC增殖、DNA合成的作用,而这些促进作用能被Ph所阻滞。③QUE和ISOR均剂量依赖地抑制NE促VSMC增殖和DNA合成的作用,且QUE和ISOR有明显的协同作用。④QUE和ISOR对NE刺激作用的抑制明显强于Ph的作用。⑤QUE和ISOR对VSMC无细胞毒作用。结论QUE和ISOR是细胞毒性很低,对VSMC的增殖、DNA合成尤其是对NE刺激的VSMC增殖、DNA合成有很强的抑制作用的天然黄酮类物质。     

腺病毒介导反义AT1R转染对大鼠血管平滑肌细胞增殖的抑制作用

目的　观察腺病毒介导反义AT1基因转染对培养的大鼠动脉平滑肌细胞 (VSMCs)增殖的影响。方法　用定向克隆和同源重组方法构建携带人反义AT1基因的复制 -缺陷型重组腺病毒 (Ad/CMV·ahAT1) ,转染体外培养的VSMCs,用RT PCR半定量法和免疫组化法检测AT1R的表达 ,用3 H TdR掺入实验和流式细胞仪检测VSMCs的DNA合成和增殖指数。结果　与对照组相比 ,转染Ad/CMV·ahAT1后 4 8h的VSMCs,AT1R的mRNA表达低 5 0 % ,蛋白表达也显著低于对照组 (P <0 0 1)。给予AngⅡ刺激的VSMCs的3 H TdR掺入量和增殖指数明显高于空白对照组 (分别为P <0 0 5和P <0 0 1) ;转染Ad/CMV·ahAT1组3 H TdR掺入量和增殖指数则显著降低 (与DMEM组比P <0 0 5 ,与AngⅡ对照组比P <0 0 1)。 结论　腺病毒介导的反义AT1R转染 ,通过抑制AT1R的表达 ,明显抑制VSMCs的增殖和AngⅡ刺激的VSMCs增殖     

欧亚旋覆花总黄酮对血管平滑肌细胞增殖和迁移的影响

目的 探讨欧亚旋覆花总黄酮(TFIB)对培养血管平滑肌细胞(VSMC)增殖及迁移的影响.方法 采用大鼠胸腹主动脉的动脉中膜平滑肌细胞,用贴块法培养,实验用4～7代细胞,加入不同浓度的TFIB共同孵育24 h.采用噻唑蓝(MTT)法观察该药对细胞增殖的影响,倒置显微镜下观察该药对细胞迁移的影响.结果 与对照组相比,TFIB对VSMC增殖具有抑制作用,该作用呈剂量依赖性;随着TFIB浓度增加体外培养的VSMC迁移距离缩短.结论 适宜浓度的TFIB可明显抑制体外培养的大鼠VSMC的增殖、迁移.     

莲心碱对自发性高血压大鼠血管平滑肌细胞增殖及对PDGF-B、bFGF、c-sis、c-myc的影响

用[~3H]胸腺嘧定核苷([~3H]TdR)掺入法、电镜、免疫组化和原位杂交方法,在自发性高血压大鼠(SHR)观察了莲心碱(Lien)对血管平滑肌细胞(VSMC)增殖的作用及对生长因子PDGFB、bFGF及其相关癌基因c-sis和c-myc表达的影响.结果发现Lien在降低SHR血压同时,能减少VSMC的线粒体,粗面内质网和[~3H]TdR掺入量,并能逆转VSMC增殖时PDGF-B、bFGF抗原及c-sis和c-myc mRNA的表达增强.提示Lien能抑制SHR的VSMC增殖,与生长因子及癌基因调控的分子生物学机制有关.     

雷公藤内酯醇对大鼠血管平滑肌细胞的增殖及DNA合成的影响

目的：探讨中药制剂雷公藤内酯醇对培养血管平滑肌细胞（VSMCs）增殖及DNA合成的影响。方法：体外培养大鼠胸主动脉平滑肌细胞，用^3H-TdR掺入率观察该药对细胞增殖和DNA合成的影响，采用流式细胞技术观察该药对细胞增殖周期的影响。结果：雷公藤内酯醇以剂量依赖性方式，抑制VSMCs的DNA合成；阻断细胞周期的中G0/G1期向DNA合成的S期转化。结论：雷公藤内酯醇能够有效地抑制VSMC的增殖，具有潜在的预防再狭窄价值。     

西拉普利对血小板源生长因子诱导的血管平滑肌细胞增殖的影响

目的为探讨西拉普利预防再狭窄及动脉粥样硬化的可能性,研究了西拉普利对血小板源生长因子(PDGF)诱导的血管平滑细胞(VSMC)增殖的影响。方法以培养的大鼠VSMG为模型、应用3H-TdR掺入试验观察VSMC增殖情况。结果PDGF能明显促进VSMCDNA合成,大剂量西拉普利能抑制PDGF诱导的细胞DNA合成,小剂量西拉普利增加细胞DNA合成。结论大剂量西拉普利能明显抑制VSMC增殖、对防治再狭窄及动脉粥样硬化可能有效。     

色素上皮衍生因子对缺氧/复氧血管平滑肌细胞增殖及凋亡的影响

目的:观察重组人源性色素上皮衍生因子（Pigment epithelium-derived factor,PEDF）对缺氧/复氧(H/R)后平滑肌细胞（vascular smooth muscle cells,VSMCs）增殖和凋亡的影响。方法:以组织贴块法培养VSMCs后,随机分为3组,即对照组、H/R模型组及模型+PEDF组。模型+PEDF组又按PEDF的浓度(50、100、200及400 ng/ml)分为4组。用MTT比色法检测VSMCs增殖的变化;用Hoechst/PI双染色法和流式细胞仪法(FCM)检测VSMCs的凋亡;用Western blot法测定凋亡相关蛋白Bcl-2、Bax的表达。结果:①MTT比色法检测显示,缺氧、复氧可促进VSMCs增殖;PEDF能够抑制VSMCs增殖,以200 ng/ml的PEDF作用更显著。Hoechst/PI双染色法和FCM检测显示,经100、200 ng/ml的PEDF作用后,VSMCs的凋亡率较对照组和H/R组明显增高(P<0.01)。与对照组和H/R组比较,Western blot检测显示,100、200 ng/ml的PEDF能够下调Bcl-2蛋白表达并上调Bax蛋白表达(P<0.05,P<0.01)。结论:H/R后,VSMCs增殖增多,PEDF可抑制H/R后VSMCs增殖,其作用可能与Bcl-2、Bax通路促进VSMCs凋亡有关。     

DNA synthesis and apoptosis in smooth muscle cells from a model of genetic hypertension

The present study was designed to assess vascular smooth muscle cell (VSMC) proliferation and apoptosis in primary cultured VSMCs prepared from the aortic tunica media of adult (4 to 5 months old) age- and gender-matched groups of stroke-prone spontaneously hypertensive rats (SHRSP) and the normotensive reference strain, Wistar-Kyoto (WKY) rats. In the present study, VSMC proliferation was assessed with measurement of DNA synthesis in response to stimulation of G(0)/G(1) arrested VSMCs with 10% serum, whereas apoptosis was measured in response to serum deprivation. Apoptosis in aortic VSMCs was assessed in vitro with the technique of Annexin V binding in combination with propidium iodide exclusion with bivariate flow cytometric analysis. The percentage of necrotic VSMCs in the cell populations was assessed simultaneously. The light-scattering properties of the cells were assessed to provide further information on cell shrinkage and chromatin condensation. Results of the present study have shown enhanced DNA synthesis in VSMCs from SHRSP (n=10; 5.2+/-0.9 cpmx10(3)/mg protein) compared with WKY (n=12; 2.4+/-0.7 cpmx10(3) /mg protein; P<0.05, 95% CI, -5271 to -296). In addition, the results of the present study have demonstrated the role of serum in the survival of VSMCs in vitro, because SHRSP VSMCs underwent significantly more apoptosis in response to insult by serum deprivation (n=13; 10.21+/-1.8%) than WKY VSMCs (n=7; 3.44+/-1.4%; P<0.01, 95% CI, -11.5 to -2.0). Thus, it appears that both proliferation and apoptosis are enhanced in synthetic phenotype aortic medial VSMCs from the SHRSP in vitro.     

Active oxygen species stimulate vascular smooth muscle cell growth and proto-oncogene expression.

Vascular smooth muscle cells (VSMCs) proliferate in response to arterial injury. Recent findings suggest that, in addition to platelet-derived growth factors, growth factors from inflammatory cells and endothelial cells at the site of injury may contribute to VSMC proliferation. We hypothesized that a common mechanism by which endothelial cells and inflammatory cells stimulate VSMC growth could be the active oxygen species (i.e., O2-, H2O2, and .OH) generated during arterial injury. Using xanthine/xanthine oxidase to generate active oxygen species, we studied the effects of these agents on VSMC growth. Xanthine/xanthine oxidase (100 microM xanthine and 5 microunits/ml xanthine oxidase) stimulated DNA synthesis in growth-arrested VSMCs by 180% over untreated cells. Administration of the scavenging enzymes superoxide dismutase and catalase demonstrated that H2O2 was primarily responsible for xanthine/xanthine oxidase-induced VSMC DNA synthesis. H2O2 directly increased VSMC DNA synthesis and cell number (maximal at 200 microM) but decreased DNA synthesis of endothelial cells and fibroblasts. This effect was protein kinase C independent: sphingosine, a potent protein kinase C inhibitor, failed to block H2O2-induced VSMC DNA synthesis. H2O2 (200 microM) stimulated c-myc and c-fos mRNA levels by fourfold and 20-fold, respectively, as compared with quiescent levels. In contrast to DNA synthesis, H2O2 induction of c-myc and c-fos mRNA was primarily protein kinase C dependent. These findings show that H2O2 specifically increases VSMC DNA synthesis and suggest a role for this oxidant in intimal proliferation, especially after arterial injury.     

多巴胺D3受体对胰岛素受体介导的促血管平滑肌细胞增殖作用的影响

目的研究多巴胺D3受体对胰岛素受体介导的促血管平滑肌细胞增殖作用的影响。方法以胚胎大鼠胸主动脉血管平滑肌细胞株(A10)为研究对象,观察在D3受体激动剂作用下,胰岛素受体促血管平滑肌细胞增殖作用的变化。利用[3H]-TdR细胞掺入实验观察细胞增殖状况,并利用免疫印迹法观察D3受体对胰岛素受体蛋白表达的影响,初步探讨D3受体影响胰岛素受体介导的促血管平滑肌细胞增殖作用的机制。结果D3受体激动剂(PD128907)本身对血管平滑肌细胞增殖没有影响,但可抑制胰岛素受体介导的促血管平滑肌细胞增殖作用。刺激D3受体可降低胰岛素受体的表达,提示D3受体可能通过影响胰岛素受体的表达,从而影响胰岛素受体促血管平滑肌细胞增殖的过程。结论D3受体对胰岛素受体介导的促血管平滑肌细胞增殖具有一定的抑制作用。     

Ascorbate Affects Proliferation of Guinea-pig Vascular Smooth Muscle Cells by Direct and Extracellular Matrix-mediated Effects

Proliferation of smooth muscle cells and deposition of extracellular matrix proteins are important events in the formation of atherosclerotic plaques. We have investigated the direct and matrix-mediated effects of ascorbate on the proliferation rate of vascular smooth muscle cells (VSMC) isolated from the guinea-pig aorta. In the presence of ascorbate, cells showed a bi-phasic growth pattern. At 125μmascorbate, [³H]-thymidine incorporation was stimulated 25%. However, higher concentrations of ascorbate gradually decreased cell-incorporated radioactivity up to 50% at 2 mmascorbate. These effects of ascorbate on DNA synthesis in VSMC were paralleled by the changes in cell number and were not due to ascorbate cytotoxicity. Alpha-tocopherol (0.1 mm), individually and in combinations with 1 mmascorbate, also inhibited DNA synthesis in VSMC. Ascorbate also influenced proliferation of smooth muscle cells through matrix-mediated effect. New VSMC culture plated on extracellular matrices deposited by smooth muscle cells in the presence of 0.1–1 mmascorbate had up to 50% lower proliferation rate than on matrices from ascorbate-deficient cells, as assessed by [³H]-thymidine incorporation. This effect was independent from alpha-tocopherol and specific inhibitors of collagen synthesis:l-azetidine-2-carboxylic acid and pyridine-2,4-dicarboxylic acid. An ascorbate-dependent matrix effect was specific for smooth muscle cells grown on VSMC and human skin fibroblast-originated matrices, but not for human vascular endothelial cells. The possible involvement of ascorbate in the regulation of smooth muscle cells proliferation by its antioxidant/pro-oxidant effects and regulation of extracellular matrix composition are discussed.     

Ca2+]i reduction increases cellular proliferation and apoptosis in vascular smooth muscle cells: relevance to the ADPKD phenotype

Cardiovascular complications are the leading cause of morbidity and mortality in autosomal dominant polycystic kidney disease. Pkd2+/- vascular smooth muscle cells (VSMCs) have an abnormal phenotype and defective intracellular Ca2+ ([Ca2+]i) regulation. We examined cAMP content in vascular smooth muscles from Pkd2+/- mice because cAMP is elevated in cystic renal epithelial cells. We found cAMP concentration was significantly increased in Pkd2+/- vessels compared with wild-type vessels. Furthermore, reducing the wild-type VSMC [Ca2+]i by Verapamil or BAPTA-AM significantly increased cellular cAMP concentration (mainly by phosphodiesterase [PDE] inhibition), the rate of VSMC proliferation (determined by direct cell counting, 3H-incorporation, FACS analysis of cells entering S phase, and quantitative Western PCNA and ERK1/2 analyses), and the rate of apoptosis (by Hoechst staining, FACS analysis of the Annexin-V positive cells, and quantitative Western Bax, cytochrome c, and activated caspase 9 and 3 analyses). The low [Ca2+]i induced VSMC proliferation was independent of cAMP/B-Raf signaling, while that of apoptosis was promoted by cAMP. In summary, Pkd2+/- VSMCs have elevated cAMP levels. This elevation can also be induced by reducing [Ca2+]i in wild-type VSMCs. The [Ca2+]i reduction and cAMP accumulation can cause an increase in both cellular proliferation and apoptosis, resembling Pkd mutant phenotype.     

Tributyrin inhibits human gastric cancer SGC-7901 cell growth by inducing apoptosis and DNA synthesis arrest

AIM: To evaluate the effects of tributyrin, a pro-drug of natural butyrate and a neutral short-chain fatty acid triglyceride, on the growth inhibition of human gastric cancer SGC-7901 cell.METHODS: Human gastric cancer SGC-7901 cells were 24-72 h. MTT assay was applied to detect the cell proliferation.[3H]-TdR uptake was measured to determine DNA synthesis.Apoptotic morphology was observed by electron microscopy and Hoechst-33258 staining. Flow cytometry and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay were performed to detect tributyrin-triggered apoptosis. The expressions of PARP, Bcl-2 and Bax were examined by Western blot assay.RESULTS: Tributyrin could initiate growth inhibition of SGC7901 cell in a dose- and time-dependent manner. [3H]-TdR uptake by SGC-7901 cells was reduced to 33.6% after 48 h control (P＜0.05). Apoptotic morphology was detected by TUNEL assay. Flow cytometry revealed that tributyrin could induce apoptosis of SGC-7901 cells in dose-dependent manner. After 48 hours incubation with tributyrin at 2 mmol.L-1, the level of Bcl-2 protein was lowered, and the level of Bax protein was increased in SGC-7901, accompanied by PARP cleavage.CONCLUSION: Tributyrin could inhibit the growth of gastric cancer cells effectively in vitro by inhibiting DNA synthesis and inducing apoptosis, which was associated with the downregulated Bcl-2 expression and the up-regulated Bax expression. Therefore, tributyrin might be a promising chemopreventive and chemotherapeutic agent against human gastric carcinogenesis.     

多巴胺D1类受体对胰岛素受体介导的血管平滑肌细胞增殖的影响

目的 观察多巴胺D1类受体对胰岛素受体介导的血管平滑肌细胞增殖的影响.方法 本研究以A10细胞为研究对象,观察刺激D1类受体对胰岛素促增殖作用的影响,并用免疫印迹研究D1类受体影响胰岛素作用的机制.细胞增殖作用采用[3H]胸腺嘧啶核苷(3H-TdR)掺入量表示.结果 胰岛素可促进A10细胞的增殖,该作用呈现浓度依赖性的.D1类受体激动剂Fenoldopam本身对A10细胞无增殖影响,但Fenoldopam通过D1类受体可完全阻断胰岛素介导的血管平滑肌细胞增殖作用.免疫印迹显示刺激D1类受体可降低胰岛素受体的蛋白表达,提示该机制可能参与了D1类受体对胰岛素受体作用的过程.结论 D1类受体对胰岛素受体介导的血管平滑肌细胞增殖具有抑制作用,该作用可能在高血压的发生发展中发挥一定作用.