芯片毛细管电泳评估脂质体介导超氧化物歧化酶减低细胞内氧化应激

超氧化物歧化酶(SOD)可用作抗氧化的药物。它能催化并清除细胞内的活性氧组分(ROS),保护细胞免受自由基的氧化破坏。但是由于SOD分子量较大,难以透过细胞膜进入细胞内,显著降低了SOD的药效。本研究用激光共聚焦荧光显微镜拍摄的荧光图像说明,纳米脂质体可介导SOD进入细胞。用芯片毛细管电泳激光诱导荧光分析法(MCE-LIF)测定单细胞中ROS和谷胱甘肽(GSH)的荧光信号强度,评估了用脂质体包裹的SOD与细胞作用的抗氧化效果。用脂质体包裹的SOD与肝癌细胞共培养2h,与直接用SOD作用于肝癌细胞相比较,细胞内ROS明显降低,GSH明显提高。实验结果说明,用脂质体包裹SOD是一种减低细胞内氧化应激的有效给药途径。

Evaluation of the Effectiveness of Superoxide Dismutases Mediated by Liposomes for Reducing Intracellular Oxidative Stress Using Microchip Electrophoresis with Laser-Induced Fluorescence

Superoxide dismutases (SOD) can be used as anti-oxidization drugs. They eliminate superoxide radicals and thus protect cells from damage induced by free radicals. However, their drug effectiveness is greatly reduced owing to their large molecular weight and impermeability to cell membrane. Fluorescent microscopy images of cells demonstrated that nano-liposome can transfer SOD into cells. The anti-oxidization action of liposome-mediated SOD has been evaluated through the determination of fluorescent intensity of intracellular reactive oxygen species (ROS) and reduced glutathione (GSH) in single cells by microchip electrophoresis with laser-Induced fluorescence. It has been observed that intracellular ROS decreased and GSH increased after incubation with SOD encapsulated liposomes for 2 h compared with direct incubating cells with SOD. The results demonstrate that the drug effectiveness of SOD for reducing intracellular oxidative stress is significantly improved by delivery of SOD mediated by liposomes.