First Author | Van Remmen H | Year | 2004 |
Journal | Free Radic Biol Med | Volume | 36 |
Issue | 12 | Pages | 1625-34 |
PubMed ID | 15182862 | Mgi Jnum | J:90710 |
Mgi Id | MGI:3044494 | Doi | 10.1016/j.freeradbiomed.2004.03.016 |
Citation | Van Remmen H, et al. (2004) Multiple deficiencies in antioxidant enzymes in mice result in a compound increase in sensitivity to oxidative stress. Free Radic Biol Med 36(12):1625-34 |
abstractText | To examine the effect of compound deficiencies in antioxidant defense, we have generated mice (Sod2(+/-)/Gpx1(-/-)) that are deficient in Mn superoxide dismutase (MnSOD) and glutathione peroxidase 1 (Gpx1) by breeding Sod2(+/-) and Gpx1(-/-) mice together. Although Sod2(+/-)/Gpx1(-/-) mice showed a 50% reduction in MnSOD and no detectable Gpx1 activity in either mitochondria or cytosol in all tissues, they were viable and appeared normal. Fibroblasts isolated from Sod2(+/-)/Gpx1(-/-) mice were more sensitive (4- to 6-fold) to oxidative stress (t-butyl hydroperoxide or gamma irradiation) than fibroblasts from wild-type mice, and were twice as sensitive as cells from Sod2(+/-) or Gpx1(-/-) mice. Whole-animal studies demonstrated that survival of the Sod2(+/-)/Gpx1(-/-) mice in response to whole body gamma irradiation or paraquat administration was also reduced compared with that of wild-type, Sod2(+/-), or Gpx1(-/-) mice. Similarly, endogenous oxidative stress induced by cardiac ischemia/reperfusion injury led to greater apoptosis in heart tissue from the Sod2(+/-)/Gpx1(-/-) mice than in that from mice deficient in either MnSOD or Gpx1 alone. These data show that Sod2(+/-)/Gpx1(-/-) mice, deficient in two mitochondrial antioxidant enzymes, have significantly enhanced sensitivity to oxidative stress induced by exogenous insults and to endogenous oxidative stress compared with either wild-type mice or mice deficient in either MnSOD or Gpx1 alone. |