title: Involvement of mitochondria and other free radical sources in normal and abnormal fetal development.
abstract: Shepard and Mackler have documented quantitative increases in mitochondrial cristae between gestational days 10 and 14 in rats accompanied by decreased glucose utilization and increased NADH oxidase activity. Findings show a shift from glycolytic to oxidative metabolism starting at around the time of implantation. Exposure to many substances that cause transient uteroplacental hypoperfusion, including cocaine, phenytoin, calcium channel blockers, and nitric oxide synthase (NOS) inhibitors, induce limb and central nervous system (CNS) malformations while sparing the heart. We have reported that isolated electron transport particles prepared from sensitive tissues show reduced NADH oxidase activities compared with insensitive heart. They also have significantly greater superoxide formation in association with significantly reduced superoxide dismutase activities. NOS inhibitors induce severe limb reductions in late gestation. Exposure is associated with hemorrhage and nitrotyrosine (NT) formation shortly after treatment. Hemorrhage, malformations, and NT formation can be significantly reduced by coadministration of PBN, allopurinol, or aminoguanidine. On the basis of these findings, we have proposed a role for the formation of reactive oxygen species (ROS) and reactive nitrogen species (RNS) in the genesis of limb reduction defects. It is important to note that limb reduction defects occur in humans ( approximately 0.22/1000) and have been associated with the agents listed above.
authors.affiliation: Birth Defects Research Laboratory, Division of Genetics and Development, Department of Pediatrics, University of Washington, Seattle, Washington 98195, USA. agf@u.washington.edu
authors.forename: Alan G
authors.initials: AG
authors.lastname: Fantel
authors.forename: Richard E
authors.initials: RE
authors.lastname: Person
mesh_terms: D000818:Animals; D004622:Embryo, Mammalian / Q000033:anatomy & histology / Q000502:physiology*; D005314:Embryonic and Fetal Development; D004791:Enzyme Inhibitors / Q000633:toxicity; D005333:Fetus / Q000033:anatomy & histology / Q000502:physiology*; D005609:Free Radicals / Q000378:metabolism*; D005947:Glucose / Q000378:metabolism; D017880:Limb Deformities, Congenital / Q000209:etiology*; D008928:Mitochondria / Q000502:physiology*; D009097:Multienzyme Complexes / Q000378:metabolism; D009247:NADH, NADPH Oxidoreductases / Q000378:metabolism; D019331:NG-Nitroarginine Methyl Ester / Q000633:toxicity; D051381:Rats; D013482:Superoxide Dismutase / Q000378:metabolism
chemical_list: D004791:Enzyme Inhibitors; D005609:Free Radicals; D009097:Multienzyme Complexes; D013482:Superoxide Dismutase; C023107:NADH oxidase; D009247:NADH, NADPH Oxidoreductases; D005947:Glucose; D019331:NG-Nitroarginine Methyl Ester