目的:探讨葛根异黄酮(Total isoflavones from pueraria lobata,TIP)对1-甲基-4-苯基吡啶离子(1-methyl-4-phenylpyri-dinium,MPP+)诱导的PC12氧化应激的保护作用及其机制。方法:以不同浓度TIP预处理体外培养的PC12细胞后,加入MPP+诱导多巴胺能神经损伤模型。采用MTT法检测PC12细胞活力,黄嘌呤氧化酶法测定SOD活力,硫代巴比妥法测定MDA含量,DTNB法测定GSH-Px活性。结果:与空白对照组比较,模型对照组细胞活力明显降低,MDA含量升高,GSH-Px和SOD活性降低,差异均具有统计学意义。与模型对照组比较,TIP组细胞活力升高,MDA含量减少,GSH-Px和SOD活性升高,差异均具有统计学意义。结论:TIP对MPP+诱导的PC12细胞氧化应激具有抑制作用,提高GSH-Px和SOD活性可能是其抗氧化作用的机制之一。
Objective： The aim of the study was to observe the effect of total isoflavones from pueraria Iobata （TIP） on D2 dopamine receptor mRNA, preproenkephalin mRNA and prodynorphin mRNA expressions in Parkinson＇s disease （PD） model cells induced by 1-methyl-4-phenylpyridinium ion （MPP^＋）. Methods： TIP was dissolved in 0.1 M NaOH and added to the culture medium at a final concentrations of 50 mg/L, 100 mg/L and 200 mg/L. Some cells （control） were exposed to 0.001 M NaOH. TIP was added to PC12 cells 30 min prior to the administration of MPP^＋. TIP and MPP^＋ remained in the culture medium for 96 h. D2 dopamine receptor mRNA, preproenkephalin mRNA and prodynorphin mRNA expressions were assayed by real-time quantitative reverse transcription-PCR. Results： The D2 dopamine receptor mRNA and preproenkephalin mRNA expressions were up-regulated in MPP^＋ group compared with the control group, and prodynorphin mRNA expression was down-regulated in that. The D2 dopamine receptor mRNA expression being down-regulated and prodynorphin mRNA expression being up-regulated in TIP group compared with the MPP^＋ group. And there was no effect of TIP on preproenkephalin gene expression in PC12 cells induced by MPP^＋. Conclusion： The results suggest that TIP down-regulates the D2 dopamine receptor mRNA expression, up-regulates prodynorphin mRNA expression and not affects preproenkephalin gene expression in PC12 cells induced by MPP^＋.
