論文發表人: 吳雨軒 (南加大化學工程與材料工程研究所博士班)
http://www.mrs.org/s_mrs/index.asp
脈衝電場技術廣泛的使用在癌症治療, 基因工程和細胞生物學上. 為了最佳化脈衝療程, 進一步了解影響細胞在脈衝作用下的敏感度是必須的. 在這個研究中, 我們借由分子模擬和細胞實驗調查了細胞膜氧化程度對電脈衝造成的細胞模穿透率的影響. T 淋巴白血病细胞被過氧化處理, 然後在細胞培養液中施加30 ns, 3 MV/m 的電脈衝. 培養液添加了YO-PRO-1(YP). YP 通常不會進入健康細胞, 然而一但細胞穿透率增加, YP 會進入細胞, 發綠色螢光.實驗結果顯示過氧化處理明顯的增加脈衝穿透引起的細胞模穿透率. 分子模擬結果顯示, 和含有低含量脂分子的系統相比, 當系統中含較高濃度的氧化脂分子時, 更少的時間和更低的電場就可以形成電場引起的親水性孔洞. 實驗結果和模擬結果相符合.
Pulsed electric field technology is used in cancer therapy, genetic engineering, and cell biology. To optimize pulsing protocols, a better understanding of the factors affecting the susceptibility of cells to electric pulse exposure is needed. In this work, the effects of membrane oxidation on electropermeabilization sensitivity are investigated by molecular dynamics (MD) simulations and in vitro cell experiments. Jurkat T lymphoblast cells were gently peroxidized and then exposed to 30 ns, 3 MV/m pulses and also to conventional electroporation pulses in medium containing YO-PRO-1 (YP), a membrane-impermeant dye that fluoresces significantly only when cell membranes become permeabilized. The results reveal that peroxidation significantly increases electroporative and nanopulse-induced influx of YP into Jurkat cells. In MD simulations we applied electric fields to phospholipid bilayers containing varying concentrations of oxidized lipid species. Systems with higher concentrations of oxidized lipids form hydrophilic electropores in significantly shorter times and at lower electric fields than do systems with lower oxidized lipid concentrations. Sites of water defect formation and electroporation appear to coincide with the clustering of oxidized lipids in the bilayer. In large-area simulations containing localized high oxidized lipid concentrations, pores formed preferentially in these oxidized regions. The presence of aldehyde and hydroperoxy oxygens on an otherwise nonpolar lipid tail appears to facilitate the penetration of water into the bilayer interior. 
