枸杞多糖对Caco-2细胞P-糖蛋白作用的影响

Effect of Lycium barbarum polysaccharide on the function and expression of P-glycoprote in Caco-2 cells

目的研究枸杞多糖(LBP)对Caco-2细胞P-糖蛋白(P-gp)功能和表达的影响。方法采用MTT法确定药物实验剂量;采用Rh-123摄取法评价P-gp的功能;利用流式细胞术与免疫荧光抗体检测P-gp的表达;采用经典的Caco-2细胞单层模型,研究P-gp外向转运这一动态过程受枸杞多糖作用后的变化。结果由MTT法得到枸杞多糖<100μg.mL-1时,细胞的存活率>90%;枸杞多糖使细胞内Rh-123累积增加,对功能表现为抑制作用;高浓度组(100μg·mL-1)枸杞多糖对P-gp表达有诱导作用;高浓度组(100μg.mL-1)枸杞多糖使Caco-2细胞单层模型外排率(ER)降低,对P-gp有抑制作用。结论枸杞多糖对P-gp功能表现为抑制作用,而对P-gp表达表现为诱导作用。

Objective To determine the effect of Lycium barbarum polysaccharide on the function and expression of P-glycoprotein（P-gp）in Caco-2 cell monolayers.Methods Cell viability of Caco-2 cells with different drug concentrations was measured by monotetrazolium colourmetric assay.The flow cytometry was used to detect the expression level of P-gp and the fluorescence intensity of rhodamine 123 and the latter showed the efflux function of P-gp.The Caco-2 cell monolayer model was built to determine the dynamic process of bi-directional transports of Rh-123.Results The cell viability of Caco-2 cells was higher than 90% when the concentration of Lycium barbarum polysaccharide was less than 100 μg·L-1 with MTT.In the rohamine accumulation assay,Lycium barbarum polysaccharide increased the cellular rhodamine concentration.Lycium barbarum polysaccharide up-regulated the expression levels of P-gp in Caco-2 cells.Lycium barbarum polysaccharide decreased the efflux rate in the Caco-2 cell monolayer model.Conclusion Lycium barbarum polysaccharide may suppress the function and up-regulate the expression level of P-gp in Caco-2 cells.