Laboratory of Experimental Endocrinology, University of Crete, School of Medicine, Heraklion, Greece.
J Nutr Biochem. 2012 Jun;23(6):656-66. doi: 10.1016/j.jnutbio.2011.03.010. Epub 2011 Jul 22.
Quercetin is a flavonol modifying a number of cell processes in different cell lines. Here, we present evidence that nonconjugated quercetin enters cells possibly via organic anion transporter polypeptides and quickly accumulates in the nucleus where it concentrates at distinct foci. Furthermore, it induces major transcriptional events with a high number of transcripts being modified over time and about 2200 transcripts being continuously influenced by the agent. The latter transcripts are related to cell cycle and adhesion, xenobiotic metabolism, immune-related factors and transcription. In addition, quercetin up-regulates the expression of estrogen receptors α and β. The overall outcome on cell fate is reflected by an inhibition of cell proliferation, cell cycle arrest in the G1 phase and reduction of the cells' migratory potential due to actin cytoskeleton disorganization. Finally, we report that the flavonol modifies the transcription and/or activity of numerous transcription factors. In conclusion, our data support the idea that quercetin may actively accumulate in discrete cell structures and exert more than just antioxidant actions on epithelial cells by regulating mechanisms related to gene transcription.
槲皮素是一种类黄酮，可调节不同细胞系中的多种细胞过程。在这里，我们提供的证据表明，非共轭槲皮素可能通过有机阴离子转运蛋白多肽进入细胞，并迅速积累在细胞核中，在细胞核中集中在特定的焦点处。此外，它会诱导主要的转录事件，随着时间的推移，大量转录本被修饰，约 2200 个转录本持续受到该物质的影响。后者的转录本与细胞周期和黏附、外源性代谢物、免疫相关因子和转录有关。此外，槲皮素还上调了雌激素受体 α 和 β 的表达。细胞命运的总体结果反映在细胞增殖的抑制、细胞周期停滞在 G1 期以及细胞迁移潜力的降低，这是由于肌动蛋白细胞骨架的紊乱。最后，我们报告说，这种类黄酮可以修饰许多转录因子的转录和/或活性。总之，我们的数据支持这样一种观点，即槲皮素可能通过调节与基因转录相关的机制，在离散的细胞结构中积极积累，并对上皮细胞发挥抗氧化作用以外的作用。
