葛根素注射液对K562/Adr细胞化疗药物敏感性及机理研究

The Inhibition Effect and Mechanism of Puerarin Injection on K562/Adr Cells by Cytotoxic Drug

目的：通过观察葛根素注射液协同化疗药物对K562／Adr白血病耐药细胞的抑制作用，探讨葛根素增加白血病耐药细胞对化疗药物的敏感性及作用机理。方法：选K562／Adr耐药细胞株作为靶细胞，采用MTT法观察不同浓度的葛根素注射液对K562／Adr耐药细胞增殖的影响，及细胞对化疗药物的敏感性。RT—PCR的方法检测葛根素对耐药相关基因（MDR1／P-gp、MRP）表达的影响。结果：①MTT法结果显示低到中等浓度的葛根素（25～100μg／mL）对15562／Adr耐药株的生长与对照组相比无显著差异（P〉0.05），但当葛根素浓度提高至250μg／mL以上时，对细胞则出现增殖抑制作用，且随浓度增加抑制作用增强。②用不同浓度的葛根素和化疗药物（Adr 1μg/mL）合用时结果显示，低浓度（25～50μg／mL）的实验组与对照组无显著差异（P〉0．05）；随着葛根素浓度增加（100～500μg／mL），Adr对细胞的抑制作用明显，即K562／Adr对Adr的敏感性与葛根素呈剂量依赖吴系。③K562／Adr细胞经葛根素（100μg/mL）处理1周后，MDR1基因表达受到抑制，是未经处理细胞的2．5倍，MRP基因表达在处理前后无明显变化；当处理1个月后，细胞中MDR1、MRP两基因表达均明显低于未经处理过的细胞，分别是未经处理细胞的2．6倍和3．5倍。结论：葛根素注射液在一定浓度下，能直接抑制白血病耐药细胞增殖，并能提高耐药细胞对化疗药物的敏感性；其机制可能通过对耐药相关基因（MDR1、MRP）表达抑制来起作用。

Objective ：To explore the inhibition effect and mechanism of Puerain Injection on leukemia cell line （K562/Adr） resisted to cytotoxic drug （ Adramycin, Adr）. Methods ： the leukemia cell line of K562/Adr resisted to Adr was used to target cells. The inhibition effect of Puerarin Injection alone and the synergy with Adr were observed by MTr method. The expressions of drug- resisted reated gene（ MDR1 and MRP） were detected by PT- PCR. Results ：①The growth of K562/Adr cells was inhibited by higher concertration of Puerarin Injection （250 ～ 500μg/mL）, but not suppressed by low or medium concentration of Puerarin Injection （25 ～ 100μg/mL） in liquid culture system.②In the combination of Puerarin Injection （ 100～ 500μg,/mL） with cytotoxic drug, K562/Adr cells became more sensitive to low concentration of cytotoxic drug （1 μg/mL Adr） ,and inhibited obviously by Puerarin Injection in the manner of dose dependence. ③Mter K562/Adr cells were treated with Puerarin Injection （ 100μg/mL） one week,the expression level of MDR1 gene in K562/Adr cells was inhibited by 2.5 - fold below untreated ceils. And the level of MRP gene was no obvious change. When treated with Puerarin Injection one month, the expression levels of MDR1 and MRP gene were also repressed obviously by 2.6 - fold and 3.5 - fold respectively. Conclusion ： Puerarin Injection could inhibit k562/Adr cells in the presence of its higher concentrations, and meanwhile enhance susceptibility of leukemia ceils to cytotoxic drugs from resistance to response. The mechanisms of Puerarin Injection may repress the expression of drug - resistance related gene （MDR1 or MRP）, enhance susceptibility of K562/Adr cells to Adramycin, and inhibit the rowth of K562/Adr ceils.