光照条件下核黄素对宫颈癌细胞的毒性作用

Toxic effects of riboflavin on cervical cancer cells under illumination

目的:观察核黄素对宫颈癌细胞的光敏损伤作用,并初步探讨其可能的作用位点。方法:体外培养宫颈癌细胞,MTT法观察无光照状态及光照状态(365 nm,照射45 min)下10、50、100、150、250μmol/L核黄素共孵育对宫颈癌细胞存活率的影响;荧光显微镜法观察10、50、100、150、250μmol/L核黄素共孵育后核黄素在宫颈癌细胞中的亚细胞定位;光学显微镜下观察单独核黄素(100μmol/L)、单独光照(365 nm,照射45 min)、核黄素(100μmol/L)+光照(365 nm,照射45 min)及正常培育组宫颈癌细胞的形态学变化。结果:与正常培育组细胞相比,无光照条件下,不同浓度核黄素共孵育组宫颈癌细胞存活率无明显改变;光照条件下,不同浓度核黄素共孵育组宫颈癌细胞存活率明显降低(P<0.05)。荧光显微镜观察结果表明,当浓度较低(25μmol/L)时,核黄素主要集中在核膜上和核内;当浓度较高(200μmol/L)时,细胞膜上也有分布。结论:光照条件下核黄素体外对宫颈癌细胞具有毒性作用,其损伤位点既涉及细胞核也涉及细胞膜,是一种综合损伤机制。

Objective:To observe photodamage effect of riboflavin on Hela cells,and preliminarily explore its subcellular localization.Methods:The survival rate of Hela cells without or with illumination(365 nm,45 min)treated by 10,50,100,150,and 250μmol/L riboflavin was observed using the MTT method.The subcellular localization of riboflavin with above concentrations in Hela cells was observed under fluorescence microscope.The morphological change of Hela cells was observed in single riboflavin(100μmol/L),single illumination(365 nm,45 min),riboflavin(100μmol/L)plus illumination(365 nm,45 min),and normal conditions under optical microscope.Results:Compared with the normal group,the survival rate of Hela cells was not changed by riboflavin co-incubation with above concentrations in non-illumination condition.However,the survival rate of Hela cells was reduced by riboflavin co-incubation under illumination(P<0.05).Fluorescence microscopy results showed that the riboflavin localized mainly in the perinuclear area and nuclear membrane when its concentration was low(25μmol/L),and also localized in the cytoplasmic membrane when its concentration was high(200μmol/L).Conclusions:The riboflavin could induce photodamage to Hela cells,the subcellular localization involves both cell nucleus and cell membrane,which is a comprehensive damage mechanism.