为了探究茶黄素单体(TF1)与表没食子儿茶素没食子酸酯(EGCG)在生物体中的吸收规律,本实验建立了体外Caco-2单层细胞模型,模拟小肠对TF1与EGCG的吸收,并研究了浓度和时间对吸收的影响。结果表明,在10~100βµmol·L-1范围内,TF1与EGCG在Caco-2单层细胞模型中的吸收呈现表观渗透系数Papp随浓度增加而上升的规律。但两者的外排率也呈现同样的规律,并且外排率上升的幅度均大于二者吸收率上升的幅度。由于TF1与EGCG在细胞单层模型中的Papp均小于1×10-6βcm·s -1,说明两者都属于难吸收的药物,但是TF1在Caco-2细胞模型中的吸收率高于EGCG。因其外排比均大于2,说明两者在细胞模型上的外排是被动转运。从吸收时间看,TF1的外排规律与EGCG一致。
In order to explore the absorption regularity of TF1 and EGCG in the organism. This research used the Caco-2 cell monolayer model in vitro to simulate the absorption of TF1 and EGCG in the small intestine. The influences of concentration and time on the absorption regularity of TF1 and EGCG in Caco-2 cell monolayer model were investigated. The results illustrated that the absorption of TF1 and EGCG in Caco-2 model showed that the apparent permeability coefficient raised with the increasing of concentrations of two compound in the range of 10~100βµmol·L-1. The efflux rates of the TF1 and EGCG showed the same rules as absorption. However, the increasing range of efflux rate was higher than that of absorption rate. The values of Papp about TF1 and EGCG in the cell model were lower than 1×10-6βcm·s -1, which indicated that both of them belonged to the kind of drugs which were difficult to absorb. However, with comparing the absorption rate, TF1 was higher than EGCG in this model. Both of efflux transport showed the passive process because the efflux rates of TF1 and EGCG were larger than 2 and higher than in cell model. Because the efflux regulation of TF1 was in accordance with EGCG by temporal variation, it suggested that both of them were the substrate of the same efflux protein.
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