Department of Metabolism and Nutrition, Instituto de Ciencia y Tecnología de Alimentos y Nutrición-ICTAN-CSIC, Madrid 28040, Spain.
Nutrients. 2013 Jul 31;5(8):2955-68. doi: 10.3390/nu5082955.
Diabetes mellitus is associated with reductions in glutathione, supporting the critical role of oxidative stress in its pathogenesis. Antioxidant food components such as flavonoids have a protective role against oxidative stress-induced degenerative and age-related diseases. Flavonoids constitute an important part of the human diet; they can be found in most plant foods, including green tea, grapes or cocoa and possess multiple biological activities. This study investigates the chemo-protective effect of a cocoa phenolic extract (CPE) containing mainly flavonoids against oxidative stress induced by tert-butylhydroperoxide (t-BOOH) on Ins-1E pancreatic beta cells. Cell viability and oxidative status were evaluated. Ins-1E cells treatment with 5-20 μg/mL CPE for 20 h evoked no cell damage and did not alter ROS production. Addition of 50 μM t-BOOH for 2 h increased ROS and carbonyl groups content and decreased reduced glutathione level. Pre-treatment of cells with CPE significantly prevented the t-BOOH-induced ROS and carbonyl groups and returned antioxidant defences to adequate levels. Thus, Ins-1E cells treated with CPE showed a remarkable recovery of cell viability damaged by t-BOOH, indicating that integrity of surviving machineries in the CPE-treated cells was notably protected against the oxidative insult.
糖尿病与谷胱甘肽减少有关，支持氧化应激在其发病机制中的关键作用。抗氧化食品成分，如类黄酮，具有对抗氧化应激诱导的退行性和与年龄相关的疾病的保护作用。类黄酮构成人类饮食的重要组成部分；它们存在于大多数植物性食物中，包括绿茶、葡萄或可可，并具有多种生物活性。本研究调查了主要含有类黄酮的可可酚提取物（CPE）对 t-BOOH 诱导的 Ins-1E 胰腺β细胞氧化应激的化学保护作用。评估了细胞活力和氧化状态。Ins-1E 细胞用 5-20 μg/mL CPE 处理 20 h 不会引起细胞损伤，也不会改变 ROS 的产生。添加 50 μM t-BOOH 2 h 会增加 ROS 和羰基含量，并降低还原型谷胱甘肽水平。CPE 预处理可显著预防 t-BOOH 诱导的 ROS 和羰基，并使抗氧化防御恢复到适当水平。因此，用 CPE 处理的 Ins-1E 细胞对 t-BOOH 损伤的细胞活力有明显的恢复，表明 CPE 处理细胞中存活机制的完整性明显受到氧化损伤的保护。
