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

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。

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

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, superoxide 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.