促红细胞生成素(EPO)对叶酸在Caco-2细胞中跨膜转运的影响  

Effects of erythropoietin(EPO)on the transport of folic acid across Caco-2monolayers

作　　者：言君凯[1] 靳桂英[1] 李豪男 杨青[1] 

机构地区：[1]复旦大学生命科学学院生物化学系,上海200433 [2]金日成综合大学生命科学系

出　　处：《复旦学报（医学版）》2014年第1期27-33,共7页Fudan University Journal of Medical Sciences

基　　金：国家自然科学基金(30873153)~~

摘　　要：目的采用人结肠腺癌细胞系（human colon adenocarcinoma cell line）Caco-2单细胞层模型观察促红细胞生成素（erythropoietin，EP0）对叶酸跨膜转运的影响。方法采用Caco-2单层细胞模型，观察不同剂量EPO（0．3、1、3U／mL）处理对叶酸在摄取与外排双向转运方面的影响。通过realtime-PCR与Westernblot观察EPO处理对质子偶联的叶酸转运体（protoncoupledfolatetransporter，PCFT）、还原叶酸载体（reducedfolatecarrier，RFC）以及多药耐药相关蛋白2（muhidrugresistance-associatedprotein2，MRP2）表达的影响。结果EPO在剂量0．3～3U／mL范围内可剂量依赖地增加叶酸在摄取方向的转运，增幅分别为31．6％、61．5％和120．5％。高剂量EPO（3U／mL）对叶酸在外排方向的转运也具有促进作用，增幅为56．9％，而中低剂量EPO（1、0．3U／mL）对叶酸外排无明显作用。叶酸转运体PCFT、RFC及MRP2均受EPO影响而表达上调，并呈剂量依赖和时间依赖关系。结论EP0可上调叶酸的摄取并呈剂量依赖关系，高剂量EPO对叶酸的摄取与外排具有双向促进作用。Objective To investigate the effect of erythropoietin （EPO） on the transport of folic acid across human colon adenocarcinoma cell line Caco-2 monolayers. Methods Transport assays of folic acid in uptake direction and efflux direction were performed in Caco-2 monolayers with or without the supplement of EPO （0.3,1 and 3 U/mL）. The effects of EPO on the expressions of folate transporters- proton coupled folate transporter （PCFT）, reduced folate carrier （RFC） and multidrug resistance- associated protein 2 （MRP2） were analyzed by real time-PCR and Western blot. Results Transporter-mediated uptake of folic acid was enhanced by EPO treatment in a dose-dependent manner, and the increasing degrees were 31.60% ,61.5% and 120.5% for 0.3,1 and 3 U/mL EPO,respectively. The etllux oi increasing degree was 56.9 were up-regulated by EPO iohc acid was enhanced only by EPO at high %. The expression levels of folate transporters dose （3 U/mL）,and the （PCFT, RFC and MRP2） in a dose- and time-dependent manner. Conclusions EPO at high does bidirectionally regulates the transport of folic acid. The uptake of folic acid was enhanced by EPO in a dose-dependent manner while the efflux of folio acid was enhanced by EPO of high dose.

关 键 词：叶酸 促红细胞生成素(EPO) CACO-2细胞 叶酸转运体 

分 类 号：Q563.8[生物学—生物化学] Q735