Santocono Marcello, Zurria Monica, Berrettini Marco, Fedeli Donatella, Falcioni Giancarlo
Medical Department, SIFI SpA, Via E. Patti 36, Lavinaio (CT), Italy.
J Photochem Photobiol B. 2007 Jul 27;88(1):1-10. doi: 10.1016/j.jphotobiol.2007.04.007. Epub 2007 May 1.
The purpose of this study was to evaluate the ability of the predominant carotenoids (lutein and zeaxanthin) of the macular pigment of the human retina, to protect SK-N-SH human neuroblastoma cells against DNA damage induced by different RNOS donors. Although astaxanthin has never been isolated from the human eye, it was included in this study because its structure is very close to that of lutein and zeaxanthin and because it affords protection from UV-light. DNA damage was induced by GSNO-MEE, a nitric oxide donor, by Na(2)N(2)O(3), a nitroxyl anion donor and by SIN-1, a peroxynitrite-generating agent. DNA damage was assessed using the comet assay, a rapid and sensitive single cell gel electrophoresis technique able to detect primary DNA damage in individual cells. The tail moment parameter was used as an index of DNA damage. The values of tail moment increased in all the samples incubated with the RNOS donors, indicating DNA impairment. Data obtained show that the ability of zeaxanthin, lutein, and astaxanthin to reduce the DNA damage depends on the type of RNOS donor and the carotenoid concentration used. All the carotenoids studied were capable of protecting against DNA damage in neuroblastoma cells when the cells were exposed to GSNO-MEE. However, a different behaviour was present when the other two RNOS donors were used. The presence of a carotenoid alone (without an RNOS donor) did not cause DNA damage. Spectrophotometric studies showed that the order with which tested carotenoids reacted with RNOS was not always in agreement with the DNA protection results. The data from this study provides additional information on the activities of the macular pigment carotenoids of the human retina.
本研究的目的是评估人类视网膜黄斑色素中的主要类胡萝卜素（叶黄素和玉米黄质）保护SK-N-SH人神经母细胞瘤细胞免受不同活性氮氧化物供体诱导的DNA损伤的能力。尽管虾青素从未在人眼中分离出来，但本研究将其纳入，因为它的结构与叶黄素和玉米黄质非常接近，并且能提供紫外线防护。DNA损伤由一氧化氮供体GSNO-MEE、硝酰阴离子供体Na(2)N(2)O(3)和过氧亚硝酸盐生成剂SIN-1诱导。使用彗星试验评估DNA损伤，彗星试验是一种快速且灵敏的单细胞凝胶电泳技术，能够检测单个细胞中的原发性DNA损伤。尾矩参数用作DNA损伤的指标。与活性氮氧化物供体孵育的所有样品中尾矩值均增加，表明DNA受损。获得的数据表明，玉米黄质、叶黄素和虾青素减少DNA损伤的能力取决于活性氮氧化物供体的类型和所用类胡萝卜素的浓度。当细胞暴露于GSNO-MEE时，所有研究的类胡萝卜素都能够保护神经母细胞瘤细胞免受DNA损伤。然而，当使用其他两种活性氮氧化物供体时，情况有所不同。单独存在类胡萝卜素（无活性氮氧化物供体）不会导致DNA损伤。分光光度研究表明，受试类胡萝卜素与活性氮氧化物反应的顺序并不总是与DNA保护结果一致。本研究的数据提供了关于人类视网膜黄斑色素类胡萝卜素活性的更多信息。
