Rosignoli Patrizia, Fuccelli Raffaela, Sepporta Maria Vittoria, Fabiani Roberto
Department of Chemistry, Biology and Biotechnologies, University of Perugia, Italy.
Food Funct. 2016 Jan;7(1):301-7. doi: 10.1039/c5fo00932d.
The co-incubation in the culture medium with hydroxytyrosol [3,4-dihydroxyphenyl ethanol (3,4-DHPEA)], the main phenolic compound present in extra-virgin olive oil, and H2O2 reduces the oxidative DNA damage in peripheral blood mononuclear cells (PBMC). In this study we investigate, by the comet assay, the ability of 3,4-DHPEA to inhibit the H2O2 induced DNA damage when pre-incubated with PBMC and then removed before the exposure of cells to H2O2. Low doses of 3,4-DHPEA (10-100 μM) pre-incubated for 30 min with PBMC reduced the DNA damage induced by the treatment with H2O2 200 μM for 5 min at 4 °C. Prolonging the exposure time up to 6 h completely prevented the DNA damage. Furthermore we extensively analysed, by the MTT assay, the anti-proliferative activities of 3,4-DHPEA on breast (MDA and MCF-7), prostate (LNCap and PC3) and colon (SW480 and HCT116) cancer cell lines and correlated these effects with the H2O2 accumulation. The concentration of H2O2 in the culture medium was measured by the ferrous ion oxidation-xylenol orange method. The proliferation of all the cell lines was inhibited but at different levels: the prostate cancer cells were more resistant to the growth inhibition with respect to breast and colon cancer cells. The ability of the different cell lines to remove H2O2 from the culture medium was inversely correlated with their sensitivity to the anti-proliferative effect of 3,4-DHPEA. Therefore, 3,4-DHPEA may act as a chemopreventive agent acting on both initiation and promotion/progression phases of carcinogenesis.
在培养基中，将特级初榨橄榄油中的主要酚类化合物羟基酪醇[3,4-二羟基苯乙醇(3,4-DHPEA)]与过氧化氢共同孵育，可减少外周血单核细胞(PBMC)中的氧化性DNA损伤。在本研究中，我们通过彗星试验研究了3,4-DHPEA在与PBMC预孵育然后在细胞暴露于过氧化氢之前去除时抑制过氧化氢诱导的DNA损伤的能力。低剂量的3,4-DHPEA(10 - 100μM)与PBMC预孵育30分钟，可减少在4°C下用200μM过氧化氢处理5分钟所诱导的DNA损伤。将暴露时间延长至6小时可完全防止DNA损伤。此外，我们通过MTT试验广泛分析了3,4-DHPEA对乳腺癌(MDA和MCF-7)、前列腺癌(LNCap和PC3)和结肠癌(SW480和HCT116)细胞系的抗增殖活性，并将这些效应与过氧化氢积累相关联。通过亚铁离子氧化-二甲苯酚橙法测量培养基中过氧化氢的浓度。所有细胞系的增殖均受到抑制，但程度不同：前列腺癌细胞对生长抑制的抗性高于乳腺癌和结肠癌细胞。不同细胞系从培养基中去除过氧化氢的能力与其对3,4-DHPEA抗增殖作用的敏感性呈负相关。因此，3,4-DHPEA可能作为一种化学预防剂，作用于致癌作用的起始和促进/进展阶段。
