透過您的圖書館登入
IP:3.84.7.255
  • 學位論文

AP-1活化對於香菸萃取物在HUVECs中誘發 黏著分子表現之探討

The role of AP-1 activation in cigarette smoke extract- induced adhesion molecule expression in HUVECs

指導教授 : 陳暉雯

摘要


流行病學指出抽煙與心血管疾病具有高度相關性,香菸燃燒後所釋出的煙霧可分為氣相與微粒相,在氣相與微粒相中均含有多種高濃度的氧化物和自由基,這些活性氧自由基被證實可導致血管內皮細胞功能受損,造成慢性發炎。當發炎反應發生時,血管內皮細胞上的黏著分子(E-selectin, VCAM-1, ICAM-1)會大量表現,這些黏著分子會促使白血球黏著及進入血管壁內,而導致動脈硬化。 本實驗將人類臍帶靜脈內皮細胞(human umbilical vein endothelial cells, HUVEC)以香菸萃取物(CSE)處理,利用西方墨點法和流式細胞儀證明CSE會誘發黏著分子(ICAM-1、E-selectin)的表現,以electrophoretic mobility shift assay (EMSA) 證明CSE、GPE、PPE具有活化轉錄因子AP-1的能力,以西方墨點法發現CSE可以誘發MAPKs中ERK1/2和JNK1的活性,但對於P38卻無影響。此外,我們也發現預處理F-actin filament抑制劑(cytochalasin D)可以部份抑制CSE所誘發的ICAM-1、E-selectin膜蛋白質表現,但是預處理ERK1/2抑制劑(PD98059)和JNK1抑制劑(SP600125)雖然可以抑制CSE所引起的ERK1/2和JNK1活性,卻對CSE誘發ICAM-1、E-selectin膜蛋白質表現影響不大。這些結果顯示,在CSE誘發ICAM-1和E-selectin膜蛋白質表現中,F-actin filament扮演重要角色,CSE雖然可以透過JNK1和ERK1/2增加AP-1的活性,但是JNK1、ERK1/2和AP-1的活化對於CSE誘發ICAM-1和E-selectin膜蛋白質表現可能不是主要的調節機制。

關鍵字

AP-1 MAPKs 黏著分子 香菸萃取物 自由基

並列摘要


Epidemiological studies demonstrated a relationship between cigarette smoking and cardiovascular disease. Smoke from burned cigarettes produces various oxidative species and free radicals in gas or particle phase. These species cause endothelial dysfunction and inflammation. Adhesion of leukocytes and activation of adhesion molecules (E-selectin, VCAM-1, ICAM-1 ) are present in atherosclerosis. In this study, CSE-induced surface expression of ICAM-1 and E-selectin in human umbilical vein endothelial cells was investigated. Also, the binding activity of transcription factors (AP-1) was determined by electrophoretic mobility shift assay (EMSA). Results showed that cigarette smoke extracts (CSE) induced AP-1 binding activity. We examined MAPKs (JNK1, ERK1/2) activities by using Western blot assay. Furthermore, CSE-stimulated phosphorylation of ERK1/2 and JNK1 was attenuated by the pretreatment with PD98059 and SP600125 respectively, although CSE-induced expression of ICAM-1 and E-selectin was not attenuated. CSE-induced surface expression of ICAM-1 and E-selectin was attenuated by the pretreatment with F-actin filament inhibitor cytochalasinD. These results suggested that HUVECs pretreated with F-actin filament inhibitor (cytochalasin D) would effectively inhibit CSE-induced expression of ICAM-1 and E-selectin, Although the ERK1/2, JNK1 and AP-1 activation was enhanced by CSE treatment, the enhanced activation may not be necessary in the expression of the ICAM-1 and E-selectin in HUVECs.

參考文獻


行政院衛生署:中華民國公共衛生概況。(2004) 台北:衛生署
林威龍,香菸燃燒之主流煙中活性含氧物種(ROS)之分析與探討,國立臺灣大學環境衛生研究所碩士論文,民國91年6月
Ambrose, J. A., and Barua, R. S. (2004). The pathophysiology of cigarette smoking and cardiovascular disease: an update. J. Am. Coll. Cardiol. 43, 1731-1737.
Anazawa, T., Dimayuga, P. C., Li, H., Tani, S., Bradfield, J., Chyu, K. Y., Kaul, S., Shah, P. K., and Cercek, B. (2004). Effect of exposure to cigarette smoke on carotid artery intimal thickening: the role of inducible NO synthase. Arterioscler. Thromb. Vasc. Biol. 24, 1652-1658.
Barua, R. S., Ambrose, J. A., Eales-Reynolds, L. J., DeVoe, M. C., Zervas, J. G., and Saha, D. C. (2001). Dysfunctional endothelial nitric oxide biosynthesis in healthy smokers with impaired endothelium-dependent vasodilatation. Circulation 104, 1905-1910.

延伸閱讀