The ascorbate‐driven reduction of extracellular ascorbate free radical by the erythrocyte is an electrogenic process

FEBS Letters

Van der Zee, Jolanda¹  Van den Broek, Peter J.A¹  VanDuijn, Martijn M¹ 

[1] Department of Molecular Cell Biology, Sylvius Laboratory, Leiden University Medical Center, P.O. Box 9503, 2300 RA Leiden, The Netherlands

关键词: Ascorbate;    Ascorbate free radical;    Plasma membrane;    Membrane potential;    Redox system;    AFR;    ascorbate free radical;    DHA;    dehydroascorbic acid;    DiSC3(5);    3;    3′-dipropylthiadicarbocyanine iodide;    ESR;    electron spin resonance;    TEMPO;    2;    2;    6;    6-tetramethylpiperidine-N-oxyl;   

DOI  :  10.1016/S0014-5793(01)02152-4

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Erythrocytes can reduce extracellular ascorbate free radicals by a plasma membrane redox system using intracellular ascorbate as an electron donor. In order to test whether the redox system has electrogenic properties, we studied the effect of ascorbate free radical reduction on the membrane potential of the cells using the fluorescent dye 3,3′-dipropylthiadicarbocyanine iodide. It was found that the erythrocyte membrane depolarized when ascorbate free radicals were reduced. Also, the activity of the redox system proved to be susceptible to changes in the membrane potential. Hyperpolarized cells could reduce ascorbate free radical at a higher rate than depolarized cells. These results show that the ascorbate-driven reduction of extracellular ascorbate free radicals is an electrogenic process, indicating that vectorial electron transport is involved in the reduction of extracellular ascorbate free radical.

【 授权许可】

Unknown