期刊
FREE RADICAL BIOLOGY AND MEDICINE
卷 44, 期 11, 页码 1926-1934出版社
ELSEVIER SCIENCE INC
DOI: 10.1016/j.freeradbiomed.2008.02.011
关键词
diffusion; fibroblasts; kinetics; near infrared; photodynamic therapy; photosensitizer; porphyrin; singlet oxygen; subcellular localization; time resolved
The roles played by singlet oxygen (O-1(2)) in photodynamic therapy are not fully understood yet. In particular, the mobility of O-1(2) within cells has been a subject of debate for the last two decades. In this work, we report on the kinetics of O-1(2) formation, diffusion, and decay in human skin fibroblasts. O-1(2) has been photosensitized by two water-soluble porphyrins targeting different subcellular organelles, namely the nucleus and lysosomes, respectively. By recording the time-resolved near-IR phosphorescence of O-1(2) and that of its precursor the photosensitizer's triplet state, we find that the kinetics of singlet oxygen formation and decay are strongly dependent on the site of generation. O-1(2) photosensitized in the nucleus is able to escape out of the cells while O-1(2) photosensitized in the lysosomes is not. Despite showing a lifetime in the microsecond time domain, O-1(2) decay is largely governed by interactions with the biomolecules within the organelle where it is produced. This observation may reconcile earlier views that singlet oxygen-induced photodamage is highly localized, while its lifetime is long enough to diffuse over long distances within the cells. (C) 2008 Elsevier Inc. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据