血小板衍生生长因子—BB对血管内皮细胞、平滑肌细胞及成纤维细胞增殖的影响

目的 观察血小板衍生生长因子—BB对培养的人血管内皮细胞、兔平滑肌细胞和人成纤维细胞增殖的影响。方法 采用培养的人脐静脉血管内皮细胞、兔动脉血管平滑肌细胞和人血管成纤维细胞，应用^3H—TdR掺入方法，观察血小板衍生生长因子—BB对三种细胞DNA合成的影响。结果 血小板衍生生长因子—BB可促进处于静止状态的三种细胞DNA的合成，并呈现出明显的浓度依赖关系，在30ng／ml的浓度时成纤维细胞DNA的合成达到高峰，在40ng／ml的浓度时内皮细胞、平滑肌细胞DNA的合成达到高峰。成纤维细胞、平滑肌细胞分别在PDCF-BB作用24h和36h年到DNA合成的高峰，内皮细胞在48h时DNA合成量最高。结论 血小板衍生生长因子—BB可明显促进培养的人脐静脉血管内皮细胞、兔动脉血管平滑肌细胞和人血管成纤维细胞的增殖。     

胰岛素对SHR大鼠血管平滑肌细胞体外增殖相关基因表达的影响

目的　探讨胰岛素对体外培养的血管平滑肌细胞 (vascularsmoothmusclecell,VSMC)增殖相关基因表达的影响。方法　用贴块法分离培养VSMC ,应用含 4 4 8个与细胞增殖相关基因靶基因芯片分析大鼠血管平滑肌细胞在胰岛素干预后基因表达的差异 ,RT PCR检测胰岛素作用后VSMC中bFGF、TGFβ、PDGF、MatrixGla和OPN各目的基因mRNA相对表达水平 ,采用免疫组织化学检测胰岛素作用后VSMC肌动蛋白 (α SMactin)。结果　胰岛素组VSMC的3 H TdR掺入值 (cpm)比对照组高 5 4 .6 % (P <0 0 1) ;基因芯片分析发现与细胞增殖相关等 36个基因的mRNA胰岛素干预前后培养的细胞表达差异 (8 0 4 % ) ;RT PCR检测MatrixGla和OPN在培养的VSMC中mRNA的表达量 ,胰岛素组明显高于对照组 (P <0 0 5 ) ,同时bFGF、TGFβ、PDGF的表达也是胰岛素组明显高于对照组 (P <0 0 5 ) ;α SMactin免疫组化结果显示对照组的α SMactin比胰岛素组染色深。结论　提示胰岛素介导大鼠血管平滑肌细胞增殖是多基因效应 ,胰岛素促进了VSMC的增殖与VSMC表型转换有关。     

槲皮素对家兔主动脉血管平滑肌细胞胞内游离钙浓度的影响

目的：探讨槲皮素（Ｑｕｅ）对智力这平滑肌细胞胞内游离钙浓度（〖Ｃａ＾２＋）〗ｉ的影响。方法：采用新一代钙荧光探剂Ｆｌｕｏ－３／ＡＭ检测Ｑｕｅ对培养的兔主动脉血管平滑肌细胞（ＡＳＭＣ）〖Ｃａ＾２＋〗ｉ在高Ｋ＾＋、去甲肾上腺素（ＮＥ）、血管紧张素Ⅱ（ＡｎｇⅡ）刺作用下的改变,并与Ｖｅｒａｐａｍｉｌ进行对照研究。结果：Ｑｕｅ（１０＾－６、１０＾－４ｍｏｌ／ｌ）呈剂量依赖性抑制高Ｋ＾＋去极化引起的〖Ｃａ＾     

血管内皮细胞对平滑肌细胞表型转化的影响

目的分析共培养时大鼠血管内皮细胞(VECs)对大鼠血管平滑肌细胞(VSMCs)表型转化的影响。方法 VSMCs直接种植于培养板表面,VECs则种植于与VSMCs相对的浮胶底面。免疫荧光方法观察和鉴定VECs和VSMCs,RT-PCR和共聚焦显微镜分析表型相关基因的表达。结果原代培养的大鼠VECs呈铺路石样形态,vWF染色阳性。原代培养的大鼠VSMCs免疫荧光染色α-SMA呈阳性。RT-PCR检测结果表明,48h共培养组VSMCs的合成表型相关基因CRBP-1、Smemb的表达水平显著高于单独培养组,分别为1.4倍、1.5倍;72h达到峰值,分别为1.7倍、2.1倍,96h开始下降;共培养组中收缩表型标记物Smoothelin-B和SM-MHC的基因表达水平在48h、72h显著低于单独培养组,96hSmoothelin-B却高于单独培养组。单独培养组上述各基因的变化趋势不变或保持稳定。免疫荧光结果显示SM-MHC蛋白表达在共培养组中96h后从下降转为升高(P<0.05)。结论在共培养体系中,血管内皮细胞对血管平滑肌细胞表型转化的作用表现为先促进向合成型转化,96h后促进向收缩型转化。     

Alteration of Human Placental Vascular Tone by Antiarrhythmic Medications In Vitro

Antiarrhythmic and Placental Vessels. Introduction : Antiarrhythmic medications are commonly used during pregnancy for treatment of maternal or fetal arrhythmias, but little is known about their effect on human placental vascular tone and, consequently, placental blood flow. The objective of this study was to evaluate the tone responses caused by antiarrhythmic medications in human placental vessels from normal term pregnancies in vitro.
Methods and Results : Isolated human placental arteries and veins from uncomplicated term pregnancies incubated in Krebs'-bicarbonate under 5% oxygen/5% carbon dioxide/balance nitrogen (PO₂ 35 to 38 torr) were exposed to cumulative doses of quinidine, procainamide, lidocaine, flecainide, propranolol, amiodarone, verapamil, digoxin, and adenosine after submaximal contraction with 5-hydroxytryptamine. The study was conducted both in the presence and absence of endothelium. The addition of the tested medications caused a significant, dose-dependent relaxation of human placental arteries and veins except for adenosine, which induced a sustained, dose-dependent contraction of human placental vessels regardless of the presence or absence of tone. Removal of the endothelium did not alter these responses.
Conclusions : Based on these results, the medications tested should have no decremental effect on placental blood flow, with the possible exception of adenosine, which causes significant. dosedependent contraction of human placental vessels in vitro. Should similar contraction be present in vivo, it may have an adverse effect on the fetus when administering adenosine to pregnant women at term or during labor.     

Autocrine Effects of Endothelin on In Vitro Proliferation of Vascular Smooth Muscle Cells from Spontaneously Hypertensive and Normotensive Rats

According to previous studies, endothelin-1 (ET-1) is the most potent growth factor in the regulation of vascular smooth muscle cell (VSMC) proliferation in spontaneously hypertensive rats (SHR). To evaluate if the dominant effect of ET-1-induced VSMC proliferation is achieved by autocrine regulation, aortic smooth muscle cells from four-week-old SHR and WKY (Wistar-Kyoto) rats were cultured in 24-well dishes, and the effects of ET-1 on VSMC proliferation were determined by (a) ³H-thymidine incorporation assays with different ET-1 blocking treatments, including a specific anti-ET-1 antibody; BQ-123, an ETA receptor blocker; and BQ-788, an ETB receptor blocker; and (b) examining the ET-1 blockade on the effects of treatment with other growth factors, including thrombin and angiotension II (AT-II). These results demonstrated that the anti-ET-1 antibody, BQ-123, BQ-788, and BQ-123 plus BQ-788 all caused dose-dependent inhibition of proliferation. A 90% inhibitory effect was observed at the maximum doses used except for BQ-123. The ET-1 receptor blockers inhibited thrombin-induced VSMC growth; however, they did not efficiently inhibit AT-II-induced VSMC growth. These results indicate that the autocrine effects of ET-1 play a predominant role in the proliferation of VSMCs from SHR and WKY rats. They also suggest that thrombin-induced VSMC growth is mediated by the autocrine effects of ET-1, and angiotensin II-induced VSMC growth is mediated by other signal pathways.     

Insulin and its analogue glargine do not affect viability and proliferation of human coronary artery endothelial and smooth muscle cells

Aims/hypothesis Present guidelines for the treatment of type 2 diabetes recommend HbA₁c values of less than 7%. As beta cell function worsens during progress of the disease, insulin therapy is often necessary to achieve this ambitious goal. However, due to peripheral insulin resistance, many patients need rather high insulin dosages. In the light of the extremely high cardiovascular risk of diabetic patients, it is important to determine whether high concentrations of insulin or its frequently used analogues are harmful to the cardiovascular system. We therefore investigated the modulatory effects of regular human insulin and its analogue glargine on proliferation and apoptosis of human coronary artery endothelial cells (HCAECs) and human coronary artery smooth muscle cells (HCASMCs).Methods Cells were treated with regular human insulin or insulin glargine. Proliferation was determined by [³H]thymidine incorporation and by flow cytometric analysis of Ki-67 expression. Apoptosis was assessed by flow cytometry (cell cycle analysis and annexin V staining) and determination of caspase-3 activity.Results HCAECs and HCASMCs treated with regular human insulin or insulin glargine did not show significant increases in DNA synthesis or Ki-67 expression. Administration of regular human insulin or insulin glargine did not modulate the extent of apoptotic events. No influence of insulin on lipoapoptotic vascular cell death could be detected.Conclusions/interpretation Taken together, neither regular human insulin nor insulin glargine influences growth and apoptosis of human coronary artery cells in vitro. Our data do not suggest that regular human insulin or insulin glargine promote atherosclerosis through mechanisms affecting the cellularity of human coronary arteries.     

In Vitro Vascular Reactivity to Endothelin: A Comparison Between Young and Old Normotensive and Hypertensive Rats

In this study we have investigated whether the vascular smooth muscle of a large capacitance artery of spontaneously hypertensive rats (SHR) is hyperresponsive to endothelin-1 and whether the arterial responsiveness to endothelin-1 is affected by aging. Isometric contractions of spirally cut aortic strips from SHR of 11, 22, 33 and 44 weeks of age and from age-matched WKY were measured in parallel. The vessels from SHR did not exhibit a greater responsiveness to endothelin-1 than those from WKY. No difference of responsiveness to the peptide was found among the arteries isolated from WKY of different ages. In contrast, a progressive decrease of responsiveness to endothelin-1 with aging was observed in SHR. This finding seems to be specific for endothelin-1, since the responsiveness to norepinephrine was unchanged. The significant decrease of aortic responsiveness in SHR with aging might be due to chronic hypertension and indicate desensitization to endothelin-1. The latter might be related to chronic in vivo hyperproduction of endothelin, either genetically determined or related to the hypertension-induced endothelial damage.     

Association between high levels of growth factors in plasma and progression of coronary atherosclerosis.

Although intimal proliferation of smooth muscle cells (SMC) is recognized as one of the key mechanisms in the development of atherosclerosis, our knowledge of the role of circulating growth factors for SMC in this process is limited. In the present study the plasma levels of platelet-derived growth factor (PDGF), beta-thromboglobulin (beta-TG), platelet factor 4 (PF 4) and total growth factor activity were determined in a group of 30 young postinfarction patients who had participated in an angiographic study of mechanisms associated with progression of coronary atherosclerosis. Significant correlations were found between the total growth factor activity in plasma and progression (r = 0.42, P < 0.05), as well as severity (r = 0.52, P < 0.01), of global coronary atherosclerosis. Attempts to identify the nature of the total growth factor activity indicated that less than 20% could be attributed to PDGF, the major serum mitogen for SMC. PDGF levels determined by radioimmunoassay were not related to progression or severity of global coronary atherosclerosis, but showed a significant association with the number and severity of distinct stenoses (r = 0.40, P < 0.05). Due to the retrospective design of this study, it is not possible to conclude whether there is a causal relationship between circulating growth factors and development of coronary atherosclerosis.     

促炎因子介导的体外培养人主动脉血管平滑肌细胞凋亡

目的 :探讨促炎因子对体外培养的人主动脉平滑肌细胞有无致凋亡作用。　　方法 :体外原代培养人主动脉平滑肌细胞 ,用免疫组化方法鉴定 ;肿瘤坏死因子 α (TNF α)和白细胞介素 1β (IL 1β)分别以浓度 2 0 μg/ml单独或二者共同与平滑肌细胞培养 3 6h ,实验分 4组 :TNF α组 (T组 )、IL 1β组 (I组 )、TNF α+IL 1β组 (TI组 )及对照组 ,采用流式细胞仪分析细胞凋亡及细胞周期。　　结果 :①细胞凋亡分析显示 :TI组两种因子的联合作用诱导人平滑肌细胞凋亡与对照组比明显增加 ,有显著性差异 (P <0 0 5 ) ,而二者单独作用未能诱导人平滑肌细胞凋亡。②细胞周期分析发现TI组在TNF α +IL 1β刺激下 ,细胞增殖能力与其他组比有明显下降 ,有显著性差异 (P <0 0 5 ) ,生长逐渐停滞 ,而二者单独作用对细胞增殖有轻微刺激作用 ,但与对照组无显著性差异。　　结论 :促炎因子TNF α和IL 1β的相互作用 ,可以诱导人平滑肌细胞凋亡。     

Statin Therapy for Vascular Failure

There is increasing evidence that statins reduce cardiovascular events such as coronary artery disease or stroke in hypercholesterolemic patients in both primary and secondary prevention. The striking benefit achieved with statin treatments in patients with a wide range of cholesterol levels cannot be attributed to their cholesterol lowering effect alone. Substantial data has recently accumulated showing that statins exert various effects on multiple targets, namely pleiotropic effects, especially targeting the concept of ‘vascular failure’, including the improvement of vascular endothelial function, inhibition of vascular smooth muscle cell proliferation and migration, anti-inflammatory actions, anti-oxidative effects or stabilization of vulnerable plaques. These effects have potential in the treatments of coronary artery disease in various settings, such as prevention of its onset as well as its progression, or plaque rupture. Statin therapy should be more extensively applied even in normolipidemic patients if there are additional risk factors such as hypertension, diabetes mellitus, or others. Furthermore, statins may be used to intervene in earlier stage risk conditions such as postprandial hyperlipidemia or hyperglycemia, insulin resistant state, masked hypertension, or metabolic syndrome to further reduce mortality or morbidity of coronary artery disease and heart failure.     

Systemic Thrombin Inhibition by Hirulog Does Not Alter Medial Smooth Muscle Cell Proliferation and Inflammatory Activation after Vascular Injury in the Rabbit

Summary. The study evaluated the role of thrombin in activation of vascular smooth muscle cells early after vascular injury. The direct thrombin inhibitor Hirulog (10 mg/kg SQ tid) or vehicle was administered to rabbits over 3 days following balloon injury to the abdominal aorta and the right iliac artery. Hirulog treatment yielded marked systemic anticoagulation as evidenced by an about 3.5-fold prolongation of quantitative thrombin time one hour after an injection, but with a reduction to almost baseline levels at the end of the dosing interval. After 3 days, proliferating cells in the right iliac artery were enumerated. The expression of intercellular adhesion molecule 1, macrophage-colony stimulating factor, tumor necrosis factor , and interleukin-1 as markers for inflammatory activation of the vessel wall was examined by immunohistochemistry and graded semiquantitatively. Mitotic indices did not differ between control and Hirulog-treated animals. There was also no difference in the expression of markers of inflammatory activation between both groups. In conclusion, thrombin inhibition by Hirulog administration does not reduce acutely (within 3 days) vascular smooth muscle cell proliferation or inflammatory activation after angioplasty. Thrombin inhibitors may therefore limit restenosis in the rabbit by acting later or via other, unknown pathways. The lack of effect of the thrombin inhibitor on the cellular events during the early phase of the response to balloon injury may explain the failure of such strategies to reduce restenosis in recent clinical trials despite effects towards acute thrombotic complications. Together, these results suggest that acute thrombin generation is not a crucial stimulus for early smooth muscle cell proliferation and inflammatory activation after vascular injury.     

血管平滑肌细胞凋亡与动脉粥样硬化研究进展

血管平滑肌细胞是构成血管壁的重要组成成分,其凋亡参与了动脉粥样硬化及再狭窄的发生发展,现就最近研究对血管平滑肌细胞凋亡诱导因素、相关基因、及其在动脉粥样硬化发生发展作用作一综述。     

Evaluation of Corrosion Behavior and In Vitro of Strontium-Doped Calcium Phosphate Coating on Magnesium

This study investigated the biocompatibility of strontium-doped calcium phosphate (Sr-CaP) coatings on pure magnesium (Mg) surfaces for bone applications. Sr-CaP coated specimens were obtained by chemical immersion method on biodegradable magnesium. In this study, Sr-CaP coated magnesium was obtained by immersing pure magnesium in a solution containing Sr-CaP at 80 °C for 3 h. The corrosion resistance and biocompatibility of magnesium according to the content of Sr-CaP coated on the magnesium surface were evaluated. As a result, the corrosion resistance of Sr-CaP coated magnesium was improved compared to pure magnesium. In addition, it was confirmed that the biocompatibility of the group containing Sr was increased. Thus, the Ca-SrP coating with a reduced degradation and improved biocompatibility could be used in Mg-based orthopedic implant applications.     

Effects of phytoestrogens on DNA synthesis and creatine kinase activity in vascular cells

BACKGROUND: The aim of this study was to assess the effect of phytoestrogens on the human vascular wall in vitro. METHODS: We compared the effects of E2 to those of genistein (G), daidzein (D), biochanin A (BA), equol (EQ), and quecertin (Qu) on 3[H] thymidine incorporation and creatine phosphokinase (CK) activity in human vascular smooth muscle cells (VSMC) and in a human endothelial cell line (E304). RESULTS: In VSMC, E2, the estrogen antagonist raloxifene (RAL), G, and D stimulated DNA synthesis at low concentrations and suppressed 3[H] thymidine incorporation at higher concentrations. In contrast, BA and EQ had a monophasic stimulatory effect on 3[H] thymidine incorporation (87% +/- 9% and 54% +/- 17%, respectively) whereas Qu had only an inhibitory effect (-36 +/- 16% at 30 nmol/L). In E304 cells, all phytoestrogens stimulated DNA synthesis in a dose-related manner. In both cell types E2, RAL as well as all phytoestrogens increased CK-specific activity. The administration of phytoestrogens to immature female rats resulted in increased CK in the aorta (Ao) (60% to 220%) and in the left ventricle of the heart (Lv) (45% to 160%). Similar increases in Ao and Lv CK were also induced by E2 and all five phytoestrogens in ovariectomized (OVX) female rats. RAL antagonized phytoestrogen-induced CK activity in human vascular cells and in the rat Ao and Lv tissue but did not block phytoestrogen effects on DNA synthesis in human VSMC. CONCLUSIONS: Although phytoestrogens have estrogen-mimetic effects on cell growth and CK in cultured human vascular cells and on CK in rat vascular tissues in vivo, the effects on human VSMC replication are highly dependent on the concentration and the particular phytoestrogen under investigation.     

内皮细胞表型改变对平滑肌细胞表型转换及迁移的作用

目的　观察内皮细胞表型改变对平滑肌细胞表型转换及迁移的作用。方法　建立Transwell共培养体系 ,将内皮细胞和平滑肌细胞分别接种于下室和上室 ,检测不同内皮表型对平滑肌细胞表型基因α SM actinmRNA表达及迁移的影响。结果　与内参照相比 ,融合生长内皮使平滑肌α SM actinmRNA表达增加 ,而对数生长内皮细胞使平滑肌α SM actinmRNA表达明显减少。对照组平滑肌细胞在基础状态下存在少量迁移 ,对数增殖内皮细胞组平滑肌迁移数比对照组增高约 4倍 (P <0 0 1) ,而融合生长内皮细胞组平滑肌迁移数仅为对照组的 0 5倍 (P <0 0 5)。结论　内皮细胞表型不同 ,对平滑肌细胞生物学特性的影响也不同 ,增殖期内皮明显减少平滑肌细胞表型基因α SM actinmR NA的表达、促进平滑肌表型向合成型转换和迁移     

辛伐他汀对大鼠平滑肌祖细胞和内皮祖细胞迁移的影响

目的观察辛伐他汀对平滑肌祖细胞(smooth muscle progenitor cell,SPC)和内皮祖细胞(endothelialprogenitor cell,EPC)迁移的影响,筛选新一代包被洗脱支架药物。方法采用密度梯度离心法获取大鼠骨髓单个核细胞,重悬于SPC培养基或EPC培养基,接种在纤维连接素包被培养板,平滑肌肌动蛋白免疫荧光染色鉴定骨髓源性SPC,激光共聚焦显微镜鉴定Dil标记乙酰化低密度脂蛋白(DiI-acLDL)和FITC标记的荆豆凝集素Ⅰ(FITC-UEA-Ⅰ)双染阳性细胞为正在分化的EPC。分别收集培养8 d的SPC和EPC,加入不同浓度辛伐他汀(0,0.01,0.1,1,10μmol/L)培养24 h。采用改良Boyden小室检测SPC和EPC迁移能力。结果辛伐他汀显著抑制SPC迁移,0.01μmol/L辛伐他汀作用24 h,迁移SPC数量减少,0.01μmol/L辛伐他汀组与对照组SPC迁移比较,差异有统计学意义(39±3 vs.44±3,n=5,P0.05)。与SPC相反,辛伐他汀显著促进EPC迁移,其促进作用随辛伐他汀浓度升高而增加,1.0μmol/L时达最大效应,1.0μmol/L辛伐他汀组与对照组EPC计数比较,差异有统计学意义(37±5 vs.6±3,n=5,P0.01)。结论辛伐他汀选择性抑制SPC迁移,促进EPC迁移,其双向调节作用呈浓度依赖性,局部应用有促进损伤血管再内皮化和抑制新内膜过度增生的可能。