林淑萍臺灣大學：醫事技術學研究所程珮瑜Cheng, Pei-YuPei-YuCheng2007-11-292018-07-062007-11-292018-07-062004http://ntur.lib.ntu.edu.tw//handle/246246/62851白藜蘆醇是一種多弁鄋漱捄M物，在釵h植物中皆有豐富的蘊藏量。之前的研究發現其具有抗氧化能力，並且具有能防止癌症的發生、惡化與進展，影響細胞內訊息傳遞路徑，促使細胞走向凋亡，或使某些未分化細胞走向分化…..等釵h生理效能。我們發現低濃度的白藜蘆醇可誘導K562細胞走向紅血球系分化。可能因為抑制細胞中DNA合成，白藜蘆醇能抑制K562細胞生長，且抑制程度隨其濃度增加而增加。進一步的研究發現其於高濃度時能使K562細胞停滯在G2/M期並誘導細胞走向細胞凋亡，此現象可經由觀察sub-G1細胞群量的增加與TUNEL染色證實。G2/M期停滯可能是細胞分裂被干擾所導致。我們針對在DNA合成與細胞分裂機制中扮演重要角色的拓樸異構酶進行研究。經體外試驗之解螺旋實驗與解連鎖反應測試發現白藜蘆醇對於拓樸異構酶的影響，發現白藜蘆醇能特異性的抑制第二型拓樸異構酶的作用。利用EMSA 與SPR的技術，發現白藜蘆醇能影響拓樸異構酶與DNA的交互作用。本篇論文是第一篇發現白藜蘆醇能抑制拓樸異構酶作用的報告。Resveratrol (3, 5, 4’-trihydroxystilbene) is a multifunctional natural product that is abundant in many plants. Previous studies have demonstrated that resveratrol is capable of inhibiting the initiation, promotion and progression of carcinogenesis; interfering with cell-signaling transduction, inducing cell apoptosis; and promoting cell differentiation. In this study, low dosage of resveratrol was found to induce erythroid differentiation in K562 cells. On the other hand, inhibition of the proliferation of K562 cells was found in highly dosage and that was likely due to the inhibition of cellular DNA synthesis. Further study showed that high dosage of resveratrol caused cell cycle arrested at G2/M phase and induced cell apoptosis, which was shown by the increases in sub-G1 cell population and TUNEL assay. The arrest of cells in G2/M phase may be caused by the disturbance of cell division. Subsequently, the study was focused on topoisomerases since they are among the important enzymes involved in the above mechanisms. In vitro relaxation and decatenation assay showed that resveratrol specifically inhibited the activity of topoisomerase II which could account for the DNA synthesis inhibition. The results obtained from electrophoretic mobility shift assay and surface plasmon resonance study indicated that the resveratrol affects the interaction of DNA duplex and topoisomerase II. This is the first report to demonstrate the inhibition of topoisomerase II by resveratrol.FIGURE CONTENTS 02 APPENDIX CONTENTS 04 ABBREVIATIONS 05 ENGLISH ABSTRACT 06 CHINESE ABSTRACT 07 1. INTRODUCTION 08 2. AIM 19 3. MATERIALS AND METHODS 20 4. RESULTS 37 5. DISCUSSION 43 FIGURES 47 TABLE 67 6. REFERENCE 68 7. APPENDIX 833213427 bytesapplication/pdfen-US拓樸異構酶白藜蘆醇K562 cell linetopoisomeraseresveratrolotherhttp://ntur.lib.ntu.edu.tw/bitstream/246246/62851/1/ntu-93-R91424004-1.pdf