Manna C, Galletti P, Cucciolla V, Moltedo O, Leone A, Zappia V
Institute of Biochemistry of Macromolecules, Medical School, Second University of Naples, Italy.
J Nutr. 1997 Feb;127(2):286-92. doi: 10.1093/jn/127.2.286.
We investigated the injurious effects of reactive oxygen metabolites on the intestinal epithelium and the possible protective role played by two olive oil phenolic compounds, (3,4-dihydroxyphenyl)ethanol and (p-hydroxyphenyl)ethanol, using the Caco-2 human cell line. We induced oxidative stress in the apical compartment, either by the addition of 10 mmol/L H2O2 or by the action of 10 U/L xanthine oxidase in the presence of xanthine (250 micromol/L); after the incubation, we evaluated the cellular and molecular alterations. Both treatments produced significant decreases in Caco-2 viability as assessed by the neutral red assay. Furthermore, we observed a significant increase in malondialdehyde intracellular concentration and paracellular inulin transport, indicating the occurrence of lipid peroxidation and monolayer permeability changes, respectively. The H2O2-induced alterations were completely prevented by preincubating Caco-2 cells with (3,4-dihydroxyphenyl)ethanol (250 micromol/L); when the oxidative stress was induced by xanthine oxidase, complete protection was obtained at a concentration of polyphenol as small as 100 micromol/L. In contrast, (p-hydroxyphenyl)ethanol was ineffective up to a concentration of 500 micromol/L. Our data demonstrate that (3,4-dihydroxyphenyl)ethanol can act as a biological antioxidant in a cell culture experimental model and that the ortho-dihydroxy moiety of the molecule is essential for antioxidant activity. This study suggests that dietary intake of olive oil polyphenols may lower the risk of reactive oxygen metabolite-mediated diseases such as some gastrointestinal diseases and atherosclerosis.
我们使用Caco-2人细胞系，研究了活性氧代谢产物对肠上皮的损伤作用，以及两种橄榄油酚类化合物，即（3,4-二羟基苯基）乙醇和（对羟基苯基）乙醇可能发挥的保护作用。我们通过添加10 mmol/L过氧化氢或在黄嘌呤（250 μmol/L）存在的情况下，利用10 U/L黄嘌呤氧化酶的作用，在顶侧区诱导氧化应激；孵育后，我们评估了细胞和分子变化。通过中性红试验评估，两种处理均使Caco-2细胞活力显著降低。此外，我们观察到丙二醛细胞内浓度显著增加，以及细胞旁菊粉转运增加，分别表明发生了脂质过氧化和单层通透性变化。用（3,4-二羟基苯基）乙醇（250 μmol/L）预孵育Caco-2细胞，可完全防止过氧化氢诱导的变化；当由黄嘌呤氧化酶诱导氧化应激时，在低至100 μmol/L的多酚浓度下即可获得完全保护。相比之下，（对羟基苯基）乙醇在浓度高达500 μmol/L时均无效。我们的数据表明，在细胞培养实验模型中，（3,4-二羟基苯基）乙醇可作为生物抗氧化剂，且该分子的邻二羟基部分对抗氧化活性至关重要。这项研究表明，通过饮食摄入橄榄油多酚可能会降低活性氧代谢产物介导的疾病风险，如某些胃肠道疾病和动脉粥样硬化。
