Incani Alessandra, Serra Gessica, Atzeri Angela, Melis Maria Paola, Serreli Gabriele, Bandino Giovanni, Sedda Piergiorgio, Campus Marco, Tuberoso Carlo I G, Deiana Monica
Department of Biomedical Sciences, University of Cagliari, Cagliari, Italy.
AGRIS Sardinia, Agricultural Research Agency of Sardinia, Sassari, Italy.
Food Chem Toxicol. 2016 Apr;90:171-80. doi: 10.1016/j.fct.2016.02.015. Epub 2016 Feb 18.
The phenolic fraction of extra virgin olive oil (EVOO) concentrates before absorption in the intestinal lumen, where it may contribute to the modulation of enterocytes response to oxidative and inflammatory stimuli. We evaluated the ability of two monovarietal EVOOs phenolic extracts, Bosana and Nera di Gonnos/Tonda di Cagliari, typical and widespread varieties in Sardinia (Italy), to counteract in enterocytes like Caco-2 cells the pro-oxidant action of oxidized lipids, tert-butyl hydroperoxide (TBH) or a mixture of oxysterols of dietary origin. We confirmed that TBH treatment causes a significant increase of ROS production, GSH depletion, increase of MDA, fatty acids hydroperoxides and 7-ketocholesterol, and showed first evidence of oxidative imbalance and cell damage due to oxysterols exposure. Preincubation of cells with the phenolic extracts significantly attenuated oxidative modifications. Bosana extract showed the highest concentration of total phenols, mainly hydroxytyrosol and tyrosol, and was the most active in presence of TBH, where the free radical scavenging activity of these simple phenols seems to be a determining factor. The two extracts were equally effective, in spite of the different composition, in presence of oxysterols, where ROS production probably occurs according to different and more complex mechanisms.
特级初榨橄榄油（EVOO）的酚类成分在肠道腔内吸收前会浓缩，在那里它可能有助于调节肠细胞对氧化和炎症刺激的反应。我们评估了两种单一品种的EVOO酚类提取物，即博萨纳（Bosana）和内拉迪贡诺斯/卡利亚里圆橄榄（Nera di Gonnos/Tonda di Cagliari），这两种在意大利撒丁岛典型且广泛种植的品种，在类似Caco-2细胞的肠细胞中对抗氧化脂质、叔丁基过氧化氢（TBH）或膳食来源的氧化甾醇混合物的促氧化作用的能力。我们证实，TBH处理会导致活性氧生成显著增加、谷胱甘肽消耗、丙二醛、脂肪酸氢过氧化物和7-酮胆固醇增加，并首次证明了氧化甾醇暴露导致的氧化失衡和细胞损伤。用酚类提取物对细胞进行预孵育可显著减轻氧化修饰。博萨纳提取物的总酚含量最高，主要是羟基酪醇和酪醇，并且在TBH存在时活性最强，这些简单酚类的自由基清除活性似乎是一个决定性因素。尽管成分不同，但在氧化甾醇存在时，这两种提取物同样有效，在氧化甾醇存在的情况下，活性氧的产生可能是通过不同且更复杂的机制发生的。
