Am80抑制血管内皮细胞增殖和血管新生内膜形成的机制研究

摘要

AIM:To explore the inhibitory effects of Am 80 on the proliferation in the vascular endothelial cells ( VECs) and neointima hyperplasia of the carotid arteries after balloon injury in the rats .METHODS:The proliferation of EA-hy926 cells were detected by cell counting and MTS assay after the cells were treated with various doses of Am 80 for 24 h.The cell cycle was analyzed by flow cytometry after the cells were stained with PI .The mRNA expression of cyclinB1, P21 and matrix metalloproteinase (MMP)-2 in the EA-Hy926 cells was detected by real-time PCR.The changes of neointi-ma hyperplasia in the carotid arteries were observed under microscope with hemotoxylin and eosin (HE) staining, and the expression of cyclinB 1 was examined by the method of immunohistochemistry .RESULTS:The proliferation of EA-Hy926 cells was obviously inhibited in a dose-dependent manner when the cells were treated with various doses of Am 80 for 24 h. The cell cycle was arrested at G2/S stage in response to Am80 treatment.The mRNA expression of P21 was increased, however , the mRNA expression of cyclinB 1 and MMP-2 was decreased when the cells were treated with Am 80 at 4 μmol/L for various times.In addition, the vivo experiment demonstrated that Am80 not only significantly reduced neointimal hy-perplasia and the thickness ratio of intima to tunicae media compared with injured group , but also inhibited cyclinB 1 ex-pression in the carotid arteries .CONCLUSION:Am80 inhibits the proliferation of VECs and neointima hyperplasia in the carotid arteries after balloon injury by promoting P 21 expression and decreasing cyclinB 1 expression .%目的：探讨维甲酸衍生物Am80抑制血管内皮细胞增殖和大鼠颈总动脉内皮剥脱术后新生内膜增生的机制。方法：用不同浓度Am80处理EA-hy926细胞24 h后，应用细胞计数和MTS细胞活力分析检测细胞的增殖情况；将Am80处理的细胞进行PI染色，用流式细胞术检测细胞周期的变化情况；通过real-time PCR方法分析Am80处理后EA-hy926细胞中cyclinB1、P21和基质金属蛋白酶（ MMP）-2表达的变化；制备SD大鼠颈总动脉内皮球囊损伤模型，通过HE和免疫组化染色方法，观察Am80对球囊损伤后新生内膜形成的影响。结果：细胞计数和MTS细胞活力分析结果显示，Am80以浓度依赖性方式抑制EA-hy926血管内皮细胞增殖；流式细胞分析显示，Am80可使EA-hy926细胞周期停滞在G2／S期；real-time PCR结果表明，Am80处理后，EA-hy926细胞中P21表达上调，cy-clinB1和MMP-2表达水平降低；内皮损伤动物模型结果显示，Am80处理后新生内膜的形成受到显著抑制。结论：Am80可通过促进P21而抑制cyclinB1表达，从而抑制血管内皮细胞增殖和血管新生内膜的形成。