Bernhard David, Schwaiger Wolfgang, Crazzolara Roman, Tinhofer Inge, Kofler Reinhard, Csordas Adam
Tyrolean Cancer Research Institute, Innrain 66, A-6020 Innsbruck, Austria.
Cancer Lett. 2003 Jun 10;195(2):193-9. doi: 10.1016/s0304-3835(03)00157-5.
Inhibition of proliferation by resveratrol of CEM-C7H2 lymphocytic leukemia cells was paradoxically associated with an enhanced cellular 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT)-reducing activity. This phenomenon was most pronounced at the sub-apoptotic concentration range of 5-20 microM resveratrol. The results of our study show that the MTT-reducing activity can be increased by the polyphenolic antioxidant resveratrol without a corresponding increase in the number of living cells and that this occurs at a concentration range of the antioxidant which is not sufficient to induce apoptosis but suffices to slow down cell growth. This phenomenon appears to be restricted to proliferation inhibitors with antioxidant properties and is cell type-specific. Thus, in determining the effects of flavonoids and polyphenols on proliferation, in certain cell types this might represent a pitfall in the MTT proliferation assay.
白藜芦醇对CEM-C7H2淋巴细胞白血病细胞增殖的抑制作用，却出人意料地与增强的细胞3-[4,5-二甲基噻唑-2-基]-2,5-二苯基四氮唑溴盐（MTT）还原活性相关。这种现象在5-20微摩尔白藜芦醇的亚凋亡浓度范围内最为明显。我们的研究结果表明，多酚类抗氧化剂白藜芦醇可提高MTT还原活性，而活细胞数量却没有相应增加，且这种情况发生在抗氧化剂的浓度范围内，该浓度不足以诱导细胞凋亡，但足以减缓细胞生长。这种现象似乎仅限于具有抗氧化特性的增殖抑制剂，且具有细胞类型特异性。因此，在确定黄酮类化合物和多酚对增殖的影响时，在某些细胞类型中，这可能是MTT增殖试验中的一个陷阱。
