紫外A(UVA,320 nm~400 nm)诱发的脂质过氧化反应是通过活性氧(ROS)介导的.在UVA照射之后,单线态氧(^1O2)和超氧阴离子(O2^-·)是细胞内最初产生的ROS,它们进一步生成过氧化氢(H2O2),羟自由基(·OH)等其它自由基.为了探讨UVA照射后最早生成的^1O2和O2^-·与细胞氧化损伤后果的关系,我们采用一种特异性检测1O2和O2^-·的高灵敏度化学发光探针MCLA(2-methyl-6-(4-methoxyphenyl)-3,7-dihydroimidazo[1,2-α]pyrazin-3-one hydrochloride)检测人外周血淋巴细胞经UVA照射后的化学发光变化.发现不同剂量UVA照射后,细胞MCLA化学发光变化和MDA浓度变化一致.结果表明UVA照射后^1O2和O2^-·的水平与由此引发的脂质过氧化损伤存在正相关关系.因此,MCLA化学发光方法可望作为一种检测UVA诱发脂质过氧化水平的简单快速方法.
Ultraviolet A (UVA, 320 nm ~ 400 nm) induced lipid peroxidation is mainly mediated by reactive oxygen species (ROS) such as singlet oxygen (^1O2), superoxide anion (O2^-·), hydrogen peroxide (H2O2), and hydroxyl radical ( ·OH). Among them, O2^-· and 1O2 seem to be the precursors of other ROS after UVA radiation. In this study, we aim to discuss the role of ^1O2 and O2^-· in UVA induced lipid peroxidation. A highly sensitive chemiluminescence (CL) probe, 2-methyl-6-(4-methoxyphenyl)-3, 7-dihydroimidazo [ 1, 2-α] pyrazin-3-one hydrochloride (MCLA) was applied to evaluate the production of O2^-·and ^1O2 in UVA induced lipid peroxidation in human peripheral lymphocytes. Lipid peroxidation degree was also detected by conventional malondialdehyde (MDA) assay. Experiment results indicate that UVA induced lipid oxidative damage has a positive relationship with ^1O2 and O2^-·level. The MCLA-dependent CL method can be used to assess the degree of UVA-induced lipid peroxidation quickly and simply.