Wrona Marta, Rózanowska Malgorzata, Sarna Tadeusz
Department of Biophysics, Faculty of Biotechnology, Jagiellonian University, Kraków, Poland.
Free Radic Biol Med. 2004 May 1;36(9):1094-101. doi: 10.1016/j.freeradbiomed.2004.02.005.
The antioxidant action of carotenoids is believed to involve quenching of singlet oxygen and scavenging of reactive oxygen radicals. However, the exact mechanism by which carotenoids protect cells against oxidative damage, particularly in the presence of other antioxidants, remains to be elucidated. This study was carried out to examine the ability of exogenous zeaxanthin alone and in combination with vitamin E or C, to protect cultured human retinal pigment epithelium cells against oxidative stress. The survival of ARPE-19 cells, subjected to merocyanine 540-mediated photodynamic action, was determined by the MTT test and the content of lipid hydroperoxides in photosensitized cells was analyzed by HPLC with electrochemical detection. We found that zeaxanthin-supplemented cells, in the presence of either alpha-tocopherol or ascorbic acid, were significantly more resistant to photoinduced oxidative stress. Cells with added antioxidants exhibited increased viability and accumulated less lipid hydroperoxides than cells without the antioxidant supplementation. Such a synergistic action of zeaxanthin and vitamin E or C indicates the importance of the antioxidant interaction in efficient protection of cell membranes against oxidative damage induced by photosensitized reactions.
类胡萝卜素的抗氧化作用被认为涉及单线态氧的猝灭和活性氧自由基的清除。然而，类胡萝卜素保护细胞免受氧化损伤的确切机制，尤其是在存在其他抗氧化剂的情况下，仍有待阐明。本研究旨在检测外源性玉米黄质单独以及与维生素E或C联合使用时，保护培养的人视网膜色素上皮细胞免受氧化应激的能力。通过MTT试验测定经部花青540介导的光动力作用处理的ARPE - 19细胞的存活率，并采用电化学检测的高效液相色谱法分析光敏细胞中脂质氢过氧化物的含量。我们发现，在α-生育酚或抗坏血酸存在的情况下，补充玉米黄质的细胞对光诱导的氧化应激具有显著更高的抗性。与未补充抗氧化剂的细胞相比，添加了抗氧化剂的细胞活力增加，脂质氢过氧化物积累减少。玉米黄质与维生素E或C的这种协同作用表明抗氧化剂相互作用在有效保护细胞膜免受光敏反应诱导的氧化损伤中的重要性。
