维生素C对左旋多巴致自由基系统动态平衡损害的保护作用

Vitamin C protects against L-DOPA-induced disruption of free radical dynamic balance in glial cell cultures

目的通过体外实验探讨维生素C对左旋多巴(L-DOPA)致胶质细胞培养液中自由基系统动态平衡损害的保护作用,防治L-DOPA加速帕金森病进展。方法在含有胶质细胞的中脑培养液中,加入L-DOPA(100μmol/L)、维生素C(200μmol/L)+L-DOPA(100μmol/L),分别在24、48和72h时间点取标本,设空白对照组,测定谷胱甘肽(GSH)的含量、谷胱甘肽过氧化物酶(GSH-Px)的活性、超氧化物歧化酶(SOD)的活力及丙二醛(MDA)的水平。结果L-DOPA100μmol/L各个时间点GSH的含量、GSH-Px的活性、SOD的活力较维生素C+L-DOPA、对照组显著的下降(P<0.05～0.01),MDA的水平显著的升高(P<0.05～0.01);维生素C+L-DOPA组各个时间点GSH的含量、GSH-Px的活性、SOD的活力、MDA的水平与对照组比较差异无统计学意义(P>0.05～0.01)。结论维生素C可增强GSH、GSH-Px、SOD水平或活性,以增强其清除自由基的能力,降低MDA的水平,维持自由基系统的动态平衡,降低L-DOPA对神经元的毒性作用。

Objective To investigate the protection by Vitamin C against L-DOPA-induced disruption of free radical dynamic balance in glial cell culture and to prevent accelerated progression of Parkinson＇s disease by L-DOPA in experimental studies. Methods Glia--containing cultures were treated with L-DOPA （100 μmol/L）, VitC （200 μmol/L） ＋L-DOPA （100 μmol/L） or nothing, Level of glutathione （GSH）, glutathione peroxidase （GSH-Px） activity, superexide dismutase （SOD） activity and malondialdehyde （MDA） contents were determined at 24h, 48h and 72h. Results At all time spots, L-DOPA alone induced a significant reduction in GSH content, GSH-Px and SOD activities （P〈0.05-0.01） and increase in MDA levels （P〈0.05-0.01） compared with VitC＋L-DOPA and blank controls. Treatment with VitC＋L- DOPA was not shown to significantly change the GSH content, GSH-Px and SOD activities and MDA levels （P〈0.05 or 0.01） at each time point, compared with blank controls. Conclusion Vit C appeared to enhance GSH content, GSH-Px and SOD activities, reduce MDA levels, maintain dynamical balance of free radicals in glial cell cultures and reduce L- DOPA toxicities on neurons.