Micronutrient Research Group, Biophysics Div., Natl. Inst. of Nutrition (Indian Council of Medical Research), Jamai Osmania, Hyderabad 500 604, India.
J Food Sci. 2010 May;75(4):H123-8. doi: 10.1111/j.1750-3841.2010.01582.x.
The effect of red wine (RW), red grape juice (RGJ), green tea (GT), and representative polyphenols on Caco-2 cell (65)Zn uptake was explored. RW, RGJ, and GT enhanced the uptake of zinc from rice matrix. Fractionation of RW revealed that enhancing activity of zinc uptake was exclusively resided in the polyphenol fraction. Among the polyphenols tested, only tannic acid and quercitin stimulated the uptake of zinc while others did not influence the uptake. In tune with these results, only tannic acid and quercitin competed with zinquin (a zinc selective fluorophore) for zinc in vitro. Although all the polyphenols tested appear to enhance the expression of metallothionein (MT), the induction was higher with tannic acid, quercitin, and RW extract. Furthermore, phytic acid abrogated the tannic acid-induced MT expression. These results suggest that polyphenol-rich beverages, tannic acid, and quercitin bind and stimulate the zinc uptake and MT expression in Caco-2 cells.
研究了红酒（RW）、红葡萄汁（RGJ）、绿茶（GT）和代表性多酚对 Caco-2 细胞（65）Zn 摄取的影响。RW、RGJ 和 GT 增强了锌从大米基质中的摄取。RW 的分级分离表明，增强锌摄取的活性仅存在于多酚部分。在所测试的多酚中，只有单宁酸和槲皮素刺激锌的摄取，而其他多酚则不影响锌的摄取。与这些结果一致，只有单宁酸和槲皮素在体外与锌选择荧光团锌喹啉（zinquin）竞争锌。尽管所有测试的多酚似乎都能增强金属硫蛋白（MT）的表达，但单宁酸、槲皮素和 RW 提取物的诱导作用更高。此外，植酸废除了单宁酸诱导的 MT 表达。这些结果表明，富含多酚的饮料、单宁酸和槲皮素结合并刺激 Caco-2 细胞中的锌摄取和 MT 表达。
