Human thioredoxin attenuates hypoxia-reoxygenation injury of murine endothelial cells in a thiol-free condition.
The adult T cell leukemia-derived factor (ADF), or human thioredoxin (hTRX), has a radical scavenging effect similar to that of N-acetyl cysteine (NAC). We have recently shown that ADF/hTRX protects the lung and the heart from ischemia-reperfusion induced injury. To elucidate mechanisms of the protective effect, a hypoxia-reoxygenation (H-R) injury model was developed using a murine endothelial cell line, cultured in a thiol-free medium. In this condition, cells became much more vulnerable to H-R injury. The viability of cells decreased significantly after 1 h of hypoxic incubation followed by 1 h of reoxygenation. The injury was reduced by ADF/hTRX (100 microM) or NAC (10 mM). These two agents also demonstrated an additive protective effect. When cells were cultured in thiol-free medium for 2 h in a normoxic condition, intracellular hydrogen peroxide production was increased, which was associated with a decrease in glutathione level. NAC (10 mM) attenuated these changes whereas ADF/hTRX (100 microM) did not. These results suggest that although both ADF/hTRX and NAC protected cells from H-R injury, the underlying mechanisms are different. Because the cytoprotective effect of ADF/hTRX occurs in the thiol-free condition, it must be mediated via a novel mechanism other than enhancing thiol uptake. The additive cytoprotective effect between ADF/hTRX and NAC suggests that we should combine these two agents clinically.
Isowa
N
N
Department of Thoracic Surgery, Faculty of Medicine, Kyoto University, Kyoto, Japan.
Yoshimura
T
T
Kosaka
S
S
Liu
M
M
Hitomi
S
S
Yodoi
J
J
Wada
H
H
D000111:Acetylcysteine / Q000494:pharmacology; D000818:Animals; D000975:Antioxidants / Q000378:metabolism; D002448:Cell Adhesion / Q000187:drug effects; D015687:Cell Hypoxia; D002460:Cell Line; D048429:Cell Size / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D016207:Cytokines / Q000494:pharmacology; D019610:Cytoprotection; D004305:Dose-Response Relationship, Drug; D004727:Endothelium / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism; D005978:Glutathione / Q000378:metabolism; D006801:Humans; D006861:Hydrogen Peroxide / Q000378:metabolism; D051379:Mice; D008815:Mice, Inbred Strains; D009363:Neoplasm Proteins / Q000494:pharmacology; D016877:Oxidants / Q000378:metabolism; D010084:Oxidation-Reduction / Q000187:drug effects; D010100:Oxygen / Q000378:metabolism*; D013438:Sulfhydryl Compounds / Q000502:physiology*; D013879:Thioredoxins / Q000494:pharmacology*
D000975:Antioxidants; D016207:Cytokines; D009363:Neoplasm Proteins; D016877:Oxidants; D013438:Sulfhydryl Compounds; C055533:adult T cell leukemia-derived factor; D013879:Thioredoxins; D006861:Hydrogen Peroxide; D005978:Glutathione; D010100:Oxygen; D000111:Acetylcysteine