Targeted disruption of the glutaredoxin 1 gene does not sensitize adult mice to tissue injury induced by ischemia/reperfusion and hyperoxia.
To understand the physiological function of glutaredoxin, a thiotransferase catalyzing the reduction of mixed disulfides of protein and glutathione, we generated a line of knockout mice deficient in the cytosolic glutaredoxin 1 (Grx1). To our surprise, mice deficient in Grx1 were not more susceptible to acute oxidative insults in models of heart and lung injury induced by ischemia/reperfusion and hyperoxia, respectively, suggesting that either changes in S-glutathionylation status of cytosolic proteins are not the major cause of such tissue injury or developmental adaptation in the Glrx1-knockout animals alters the response to oxidative insult. In contrast, mouse embryonic fibroblasts (MEFs) isolated from Grx1-deficient mice displayed an increased vulnerability to diquat and paraquat, but they were not more susceptible to cell death induced by hydrogen peroxide (H(2)O(2)) and diamide. A deficiency in Grx1 also sensitized MEFs to protein S-glutathionylation in response to H(2)O(2) treatment and retarded deglutathionylation of the S-glutathionylated proteins, especially for a single prominent protein band. Additional experiments showed that MEFs lacking Grx1 were more tolerant to apoptosis induced by tumor necrosis factor alphaplus actinomycin D. These findings suggest that various oxidants may damage the cells via distinct mechanisms in which the action of Grx1 may or may not be protective and Grx1 may exert its function on specific target proteins.
Ho
Ye-Shih
YS
Institute of Environmental Health Sciences and Department of Biochemistry and Molecular Biology, Wayne State University, Detroit, MI 48201, USA. yho@wayne.edu
Xiong
Ye
Y
Ho
Dorothy S
DS
Gao
Jinping
J
Chua
Balvin H L
BH
Pai
Harish
H
Mieyal
John J
JJ
D000818:Animals; D017209:Apoptosis / Q000187:drug effects / Q000502:physiology; D002460:Cell Line; D003609:Dactinomycin / Q000494:pharmacology; D003958:Diamide / Q000737:chemistry; D004178:Diquat / Q000633:toxicity; D004220:Disulfides / Q000378:metabolism; D005347:Fibroblasts; D018390:Gene Targeting / Q000379:methods; D054477:Glutaredoxins / Q000737:chemistry / Q000172:deficiency* / Q000235:genetics / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000633:toxicity; D018496:Hyperoxia / Q000201:enzymology* / Q000235:genetics / Q000473:pathology; D008168:Lung / Q000098:blood supply / Q000378:metabolism / Q000473:pathology*; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D015428:Myocardial Reperfusion Injury / Q000201:enzymology* / Q000235:genetics / Q000473:pathology; D009206:Myocardium / Q000201:enzymology / Q000473:pathology; D018384:Oxidative Stress; D010269:Paraquat / Q000633:toxicity; D017382:Reactive Oxygen Species / Q000737:chemistry / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
D004220:Disulfides; C516006:Glrx protein, mouse; D054477:Glutaredoxins; D017382:Reactive Oxygen Species; D014409:Tumor Necrosis Factor-alpha; D003958:Diamide; D003609:Dactinomycin; D004178:Diquat; D006861:Hydrogen Peroxide; D010269:Paraquat