Tourniaire Franck, Hassan Meryl, André Marc, Ghiringhelli Odette, Alquier Christian, Amiot Marie-Josèphe
UMR U-476 INSERM/U-1260 INRA, Faculté de Médecine, 27 Boulevard Jean Moulin, 13385 Marseille Cedex 5, France.
Mol Nutr Food Res. 2005 Oct;49(10):957-62. doi: 10.1002/mnfr.200500088.
Naringin, the main flavanone of grapefruit, was reported to display numerous biological effects: antioxidant, hypocholesteremic, anti-atherogenic and favoring drug absorption. Naringin absorption mechanisms were studied in Caco-2 cells (TC7 clone). We investigated the possible involvement of several membrane transporters implicated in polyphenolic compounds intestinal transport (sodium-dependent glucose transporter 1, monocarboxylate transporter, multidrug-associated resistance proteins 1 and 2, and P-glycoprotein). Naringin was poorly absorbed by Caco-2 cells, according to its low value of apparent permeability coefficient (P(app) = 8.1 +/- 0.9 x 10(-8) cm/s). In the presence of verapamil, a specific inhibitor of P-glycoprotein, cellular uptake was increased by almost threefold after 5 min, and P(app) was doubled after 30 min. Our results indicated the involvement of P-glycoprotein, an ATP-driven efflux pump, capable of transporting naringin from the Caco-2 cell to the apical side. This phenomenon could explain, at least in part, the low absorption of this flavanone at the upper intestinal level.
柚皮苷是葡萄柚的主要黄烷酮，据报道具有多种生物学效应：抗氧化、降胆固醇、抗动脉粥样硬化以及促进药物吸收。在Caco-2细胞（TC7克隆）中研究了柚皮苷的吸收机制。我们研究了几种参与多酚类化合物肠道转运的膜转运蛋白（钠依赖性葡萄糖转运蛋白1、单羧酸转运蛋白、多药耐药相关蛋白1和2以及P-糖蛋白）可能发挥的作用。根据其较低的表观渗透系数值（P(app) = 8.1 +/- 0.9 x 10(-8) cm/s），Caco-2细胞对柚皮苷的吸收较差。在维拉帕米（一种P-糖蛋白特异性抑制剂）存在的情况下，5分钟后细胞摄取量增加了近三倍，30分钟后P(app)增加了一倍。我们的结果表明P-糖蛋白（一种ATP驱动的外排泵）参与其中，它能够将柚皮苷从Caco-2细胞转运到顶端侧。这种现象至少可以部分解释这种黄烷酮在上肠道水平的低吸收情况。
