| 摘要: | 動脈壁血管平滑肌細胞異常增生是動脈粥狀硬化（atherosclerosis）和血管成形術後再狹窄(restenosis)的一個重要致病因子。瘦體素(Leptin)是一種胜?荷爾蒙(peptide hormone)，在控制體重上佔有重要的地位，Leptin也會增加潛在的動脈粥樣硬化機會，如誘導血管內皮功能損傷、遷移、肥厚和血管平滑肌細胞增生。阿魏酸為當歸、川芎乾燥根莖的有效成分之一，研究已指出阿魏酸具有改善血液動力學、抗發炎和抗氧化等藥理作用。阿魏酸乙酯（FAEE）為阿魏酸的酯類衍生物，目前已知具有抗血栓、鎮痛、調節免疫功能。因此，本研究以Leptin (10 ng/mL)誘發大鼠主動脈平滑肌細胞(A10細胞)增生及遷移，模擬肥胖者誘發心血管疾病模式，探討FAEE是否能抑制由Leptin誘導的A10細胞增生及遷移作用，並進一步了解其作用機制。本實驗利用A10細胞分別給予Leptin 0.06, 0.6, 6 nM (1, 10, 100 ng/mL) 72小時後進行細胞增生觀察，實驗結果發現，Leptin具有濃度依賴性的誘導A10細胞增生。同時Leptin可增加p44/42 MAPK 磷酸化反應，且具有濃度依賴性。若先給予U0126 (MAPK inhibitor)處理，則Leptin誘發A10細胞增生及p44/42 MAPK 磷酸化作用均受到抑制，由此可推論Leptin誘發A10細胞增生與p44/42 MAPK 磷酸化反應相關。同時，實驗結果也發現Leptin可增加細胞週期調控蛋白 cyclin D1、p21cip1、β-catenine 蛋白質表現，降低CDKs 抑制劑 p27Kip1 蛋白質表現量。若將A10細胞預先給予FAEE (1,10 μM)處理後可抑制 Leptin (10 ng/mL) 誘導的 p44/42 MAPK 磷酸化作用以及cyclin D1、p21cip1、β-catenine 蛋白質表現，同時增加p27Kip1 蛋白質表現量。除此之外，在細胞遷移實驗（Transwell Assay）中，將A10細胞種至Transwell insert中，細胞會爬行穿越底層的微膜（semipermeable membrance），由此可知Leptin具有濃度依賴性的誘導A10細胞遷移。而FAEE (1,10 μM) 透過降低Leptin (10 ng/mL) 誘發之A10細胞中 MMP-2、MMP-9 蛋白質表現量，明顯抑制 Leptin (10 ng/mL) 誘發A10細胞的遷移作用。因此我們認為FAEE為預防治療因肥胖所引發動脈粥狀硬化極具潛能治療之用藥。
The abnormal proliferation of vascular smooth muscle cells (VSMCs) in arterial wall is an important pathogenic factor for vascular disorders such as atherosclerosis and restenosis after angioplasty. Leptin is a peptide hormone which plays a central role in the regulation of body weight. Leptin exerts many potentially atherogenic effects such as induction of endothelial dysfunction, migration, hypertrophy and proliferation of VSMC. Ferulic Acid is widely exist in Angelica sinensis, Ligusticum chuanxiong and so on Chinese medicine, has been approved for anti-inflammatory and antioxidant properties. Ferulic Acid Ethyl Ester (FAEE) is an ester derivative of ferulic acid, the latter known for its anti-thrombus, analgesia, and regulation of immunologic function. The aim of this study was to investigate whether FAEE can inhibit the proliferation and migration of vascular smooth muscle cells induced by leptin and the possible molecular mechanism of its action. Rat aortic smooth muscle cells (A10 cells) were serum-starved and subsequently treated with leptin at increasing concentrations (1, 10, 100 ng/mL) for 72h. Both of cell proliferation and migration were measured when the cell treated with leptin and/or FAEE in A10 cells. Phosphorylated p44/42 MAPK, cyclin D1, p21cip1, β-catenine, p27Kip1, MMP-2, MMP-9 protein level were also measured in A10 cells. Results demonstrated that leptin increased the proliferation of A10 cells as well as the phosphorylation of p44/42 MAPK in a concentration-dependent manner in A10 cells. These effect of leptin were significantly reduced by the pretreatment of U0126, a MAPK inhibitor, in A10 cells. There results suggested that leptin-induced cell proliferation were through the phosphorylation of p44/42 MAPK. Furthermore, leptin also significantly increased the expression of cyclin D1, p21cip1 and β-catenine protein, as well as decreased the expression of p27Kip1, a cyclin-dependent kinase inhibitor, in A10 cells. Above effect of leptin were significantly reduced by the pretreatment of FAEE (1, 10 μM) in A10 cells. In transwell migration assay, the A10 cells were seeded into the insert and move through the pores of the membrane at the bottom of the insert. Leptin (10, 100 ng/mL) significantly increased the migration of A10 cells in a concentration-dependent manner. Meanwhile, the expression of MMP-2 and MMP-9 protein were significantly increased when the cell treated with leptin (10 ng/mL). Pretreatment of FAEE (1, 10 μM) significantly inhibited the migration of cells and the expression of MMP-2 and MMP-9 protein induced by leptin (10 ng/mL) in A10 cells. In conclusion, FAEE significantly attenuated the proliferation and migration of cell induced by leptin through the regulation of p44/42 MAPK, cell cycle protein, and MMPs. Therefore, this study provides a rationale for the therapeutic use of FAEE in atherosclerosis. |
