Embryonic fibroblasts from Gpx4+/- mice: a novel model for studying the role of membrane peroxidation in biological processes.
A previous study using mice null for Gpx4 indicates that PHGPx plays a critical role in antioxidant defense and is essential for the survival of the mouse. In the present study, we further analyzed the stress response of MEFs (murine embryonic fibroblasts) derived from mice heterozygous for the Gpx4 gene (Gpx4(+/-) mice). MEFs from Gpx4(+/-) mice have a 50% reduction in PHGPx expression without any changes in the activities of other major antioxidant defense enzymes. Compared to MEFs from Gpx4(+/+) mice, MEFs from Gpx4(+/-) mice were more sensitive to exposure to the oxidizing agent t-butyl hydroperoxide (t-BuOOH), and t-BuOOH exposure induced increased apoptosis in MEFs from Gpx4(+/-) mice. When cultured at low cell density, MEFs from Gpx4(+/-) mice also showed retarded growth under normal culture conditions (20% oxygen) that was reversed by culturing under low oxygen (2% oxygen). In addition, oxidative damage was increased in the MEFs from the Gpx4(+/-) mice, as indicated by increased levels of F(2)-isoprostanes and 8-oxo-2-deoxyguanosine in these cells. Our data demonstrate that MEFs from Gpx4(+/-) mice are more sensitive to oxidative stress because of reduced expression of PHGPx.
Department of Physiology, University of Texas Health Science Center at San Antonio, San Antonio TX 78229-3900, USA.
Qitao
Q
Ran
Holly
H
Van Remmen
Mingjun
M
Gu
Wenbo
W
Qi
L Jackson
LJ
Roberts
Tomas
T
Prolla
Arlan
A
Richardson
D000080242:8-Hydroxy-2'-Deoxyguanosine; D000818:Animals; D000975:Antioxidants / Q000378:metabolism; D053148:Caspase 3; D020169:Caspases / Q000378:metabolism; D002374:Catalase / Q000378:metabolism; D002455:Cell Division / Q000187:drug effects; D002462:Cell Membrane / Q000378:metabolism*; D002478:Cells, Cultured; D003849:Deoxyguanosine / Q000031:analogs & derivatives* / Q000378:metabolism; D028441:F2-Isoprostanes / Q000378:metabolism; D005260:Female; D005347:Fibroblasts; D017353:Gene Deletion; D005979:Glutathione Peroxidase / Q000172:deficiency / Q000235:genetics* / Q000378:metabolism*; D006579:Heterozygote; D015227:Lipid Peroxidation; D008297:Male; D051379:Mice; D008822:Mice, Transgenic; D010084:Oxidation-Reduction; D018384:Oxidative Stress; D010100:Oxygen / Q000494:pharmacology; D000080662:Phospholipid Hydroperoxide Glutathione Peroxidase; D013482:Superoxide Dismutase / Q000378:metabolism
D000975:Antioxidants; D028441:F2-Isoprostanes; D000080242:8-Hydroxy-2'-Deoxyguanosine; D000080662:Phospholipid Hydroperoxide Glutathione Peroxidase; D002374:Catalase; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase; C505409:Casp3 protein, mouse; D053148:Caspase 3; D020169:Caspases; D003849:Deoxyguanosine; D010100:Oxygen