Transgenic mice overexpressing glutathione peroxidase 4 are protected against oxidative stress-induced apoptosis.
Glutathione peroxidase 4 (Gpx4) is uniquely involved in the detoxification of oxidative damage to membrane lipids. Our previous studies showed that Gpx4 is essential for mouse survival and that Gpx4 deficiency makes cells vulnerable to oxidative injury. In the present study, we generated two lines of transgenic mice overexpressing Gpx4 (Tg(GPX4) mice) using a genomic clone containing the human GPX4 gene. Both lines of Tg-(GPX4) mice, Tg5 and Tg6, had elevated levels of Gpx4 (mRNA and protein) in all tissues investigated, and overexpression of Gpx4 did not cause alterations in activities of glutathione peroxidase 1, catalase, Cu/Zn superoxide dismutase, and manganese superoxide dismutase. The human GPX4 transgene rescued the lethal phenotype of null mutation of the mouse Gpx4 gene, indicating that the transgene can replace the essential role of mouse Gpx4 in mouse development. Cell death induced by t-butylhydroperoxide and diquat was significantly less in murine embryonic fibroblasts from Tg(GPX4) mice compared with wild type mice. Liver damage and lipid peroxidation induced by diquat were reduced significantly in Tg(GPX4) mice. In addition, diquat-induced apoptosis was decreased in Tg(GPX4) mice, as evidenced by attenuated caspase-3 activation and reduced cytochrome c release from mitochondria. These data demonstrate that Gpx4 plays a role in vivo in the mechanism of apoptosis induced by oxidative stress that most likely occurs through oxidative damage to mitochondrial phospholipids such as cardiolipin.
Ran
Qitao
Q
Department of Cellular and Structural Biology, University of Texas Health Science Center at San Antonio, 7400 Merton Mintor Boulevard, San Antonio, TX 78229, USA.
Liang
Hanyu
H
Gu
Minjun
M
Qi
Wenbo
W
Walter
Christi A
CA
Roberts
L Jackson
LJ
Herman
Brian
B
Richardson
Arlan
A
Van Remmen
Holly
H
D000410:Alanine Transaminase / Q000097:blood; D000818:Animals; D000975:Antioxidants / Q000494:pharmacology; D017209:Apoptosis; D015152:Blotting, Northern; D015153:Blotting, Western; D002308:Cardiolipins / Q000378:metabolism; D053148:Caspase 3; D020169:Caspases / Q000378:metabolism; D002374:Catalase / Q000378:metabolism; D002470:Cell Survival; D002478:Cells, Cultured; D045304:Cytochromes c / Q000378:metabolism; D004178:Diquat / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004789:Enzyme Activation; D028441:F2-Isoprostanes / Q000097:blood; D005260:Female; D005347:Fibroblasts / Q000378:metabolism; D015723:Gene Library; D005979:Glutathione Peroxidase / Q000096:biosynthesis* / Q000378:metabolism; D006540:Herbicides / Q000494:pharmacology; D006801:Humans; D015227:Lipid Peroxidation; D008099:Liver / Q000378:metabolism; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D008928:Mitochondria / Q000378:metabolism; D008957:Models, Genetic; D018384:Oxidative Stress; D000080662:Phospholipid Hydroperoxide Glutathione Peroxidase; D012313:RNA / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D013482:Superoxide Dismutase / Q000378:metabolism; D014018:Tissue Distribution; D019076:Transgenes; D020122:tert-Butylhydroperoxide / Q000494:pharmacology; D000094765:Glutathione Peroxidase GPX1
D000975:Antioxidants; D002308:Cardiolipins; D028441:F2-Isoprostanes; D006540:Herbicides; D012333:RNA, Messenger; D012313:RNA; D045304:Cytochromes c; D020122:tert-Butylhydroperoxide; D004178:Diquat; D000080662:Phospholipid Hydroperoxide Glutathione Peroxidase; D002374:Catalase; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase; D000410:Alanine Transaminase; C505407:CASP3 protein, human; C505409:Casp3 protein, mouse; D053148:Caspase 3; D020169:Caspases; D000094765:Glutathione Peroxidase GPX1