Environmental Bioprocesses Laboratory, AUF Regional Excellence Pole (AUF-PER-LBP), Sfax Biotechnology Center, Sfax, Tunisia.
Food Chem Toxicol. 2011 Jan;49(1):179-84. doi: 10.1016/j.fct.2010.10.014. Epub 2010 Oct 16.
Throughout the history, olive (Olea europea L.) leaves have been heavily exploited for the prevention or the treatment of hypertension, carcinogenesis, diabetes, atherosclerosis and so many other traditional therapeutic uses. These activities are thought to be the output of olive micronutrients especially polyphenols. Hydroxytyrosol and oleuropein are considered as major polyphenolic compounds in olive leaf. In this work, a hydroxytyrosol rich olive leaves extract was investigated for potential anti-tumoral activities. In vitro cytotoxic effects against MCF-7 breast cancer cells were examined using MTT and neutral red tests. The anti-tumor activities were further investigated by flow cytometry and western blotting. Cytotoxicity assays resulted in a dose dependent growth inhibition of MCF-7 cells. This inhibition was due to the cell cycle arrest in the G0/G1 phase. The understanding of the molecular mechanism by which olive leaves extract arrested cell growth showed a down-expression of the peptidyl-prolyl cis-trans isomerase Pin1 which in turn decreased the level of a G1 key protein; Cyclin D1. Additionally, olive leaves extract treatment up-regulated the AP1 transcription factor member, c-jun. Therefore, olive leaves extract will necessitate further deep investigation for a probable use as a cancer preventive food additive.
在整个历史中，橄榄（Olea europaea L.）叶一直被广泛用于预防或治疗高血压、致癌、糖尿病、动脉粥样硬化等许多传统的治疗用途。这些活动被认为是橄榄微量营养素（特别是多酚）的作用。羟基酪醇和橄榄苦苷被认为是橄榄叶中的主要多酚化合物。在这项工作中，研究了一种富含羟基酪醇的橄榄叶提取物的潜在抗肿瘤活性。使用 MTT 和中性红试验检测了对 MCF-7 乳腺癌细胞的体外细胞毒性作用。通过流式细胞术和 Western blot 进一步研究了抗肿瘤活性。细胞毒性试验导致 MCF-7 细胞的生长呈剂量依赖性抑制。这种抑制是由于细胞周期停滞在 G0/G1 期。对橄榄叶提取物阻止细胞生长的分子机制的理解表明，肽基脯氨酰顺反异构酶 Pin1 的表达下调，进而降低了 G1 关键蛋白 cyclin D1 的水平。此外，橄榄叶提取物处理还上调了 AP1 转录因子成员 c-jun。因此，橄榄叶提取物可能需要进一步深入研究，作为一种预防癌症的食品添加剂。
