Hemin-induced membrane sulfhydryl oxidation: possible involvement of thiyl radicals.
Sublytic levels (microM) of hemin destabilized RBC membrane as indicated by ghost fragmentation pattern using a laser viscodiffractometer. Furthermore, electron microscopic study shows that 5 microM of hemin induced echinocytic transformation whereas higher hemin concentration (40 microM) induced spherocytic transformation. In addition, hemin oxidized sulfhydryl groups in a dose dependent fashion and Electron Spin Resonance study suggests that such oxidation may involve a thiyl radical. Moreover, sulfhydryl compounds enhanced hemin-induced lipid peroxidation. Desferroxamine could prevent hemin-induced sulfhydryl oxidation as well as hemin-induced decrease in membrane stability. In contrast, vitamin E could effectively prevent hemin-induced lipid peroxidation but could not prevent hemin-mediated membrane destabilization.
Chiu
D T
DT
School of Medical Technology, Chang Gung College of Medicine & Technology, Kwei-Shan, Tao-Yuan, Taiwan. dtychiu@cguaplo.cgu.edu.tw
Huang
T Y
TY
Hung
I J
IJ
Wei
J S
JS
Liu
T Z
TZ
Stern
A
A
D003676:Deferoxamine / Q000494:pharmacology; D004578:Electron Spin Resonance Spectroscopy; D004910:Erythrocyte Membrane / Q000187:drug effects / Q000378:metabolism*; D004912:Erythrocytes / Q000187:drug effects / Q000378:metabolism / Q000502:physiology; D005609:Free Radicals / Q000378:metabolism; D005978:Glutathione / Q000378:metabolism / Q000494:pharmacology; D006427:Hemin / Q000494:pharmacology*; D006801:Humans; D015227:Lipid Peroxidation / Q000187:drug effects; D008623:Mercaptoethanol / Q000494:pharmacology; D010084:Oxidation-Reduction; D013438:Sulfhydryl Compounds / Q000378:metabolism*; D017392:Thiobarbituric Acid Reactive Substances / Q000378:metabolism; D014810:Vitamin E / Q000494:pharmacology
D005609:Free Radicals; D013438:Sulfhydryl Compounds; D017392:Thiobarbituric Acid Reactive Substances; D014810:Vitamin E; D008623:Mercaptoethanol; D006427:Hemin; D005978:Glutathione; D003676:Deferoxamine