Ascorbate prevents placental oxidative stress and enhances birth weight in hypoxic pregnancy in rats.

TitleAscorbate prevents placental oxidative stress and enhances birth weight in hypoxic pregnancy in rats.
Publication TypeJournal Article
Year of Publication2012
AuthorsRichter HG, Camm EJ, Modi BN, Naeem F, Cross CM, Cindrova-Davies T, Spasic-Boskovic O, Dunster C, Mudway IS, Kelly FJ, Burton GJ, Poston L, Giussani DA
JournalJ Physiol
Volume590
IssuePt 6
Pagination1377-87
Date Published2012 Mar 15
ISSN1469-7793
KeywordsAnimals, Animals, Newborn, Anoxia, Antioxidants, Ascorbic Acid, Birth Weight, Catalase, Cysteine, Disease Models, Animal, Female, Hematocrit, Oxidative Stress, Placenta, Pregnancy, Pregnancy Complications, Rats, Rats, Wistar, Superoxide Dismutase, Uric Acid
Abstract

This study isolated the effects of maternal hypoxia independent of changes in maternal nutrition on maternal circulatory and placental molecular indices of oxidative stress and determined whether maternal antioxidant treatment conferred protection. Pregnant rats were subjected to normoxic pregnancy or 13% O2 chronic hypoxia for most of gestation with and without maternal treatment with vitamin C in the drinking water. Maternal hypoxia with and without vitamin C did not affect maternal food or water intake and led to a significant increase in maternal and fetal haematocrit. At gestational day 20, maternal plasma urate and L-cysteine concentrations, and placental levels of 4-hydroxynonenal and heat shock protein 70 were increased while placental heat shock protein 90 levels were decreased in hypoxic pregnancy. The induction of maternal circulatory and placental molecular indices of oxidative stress in hypoxic pregnancies was prevented by maternal treatment with vitamin C. Maternal hypoxia during pregnancy with or without vitamin C increased placental weight, but not total or compartmental volumes. Maternal treatment with vitamin C increased birth weight in both hypoxic and normoxic pregnancies. The data show that maternal hypoxia independent of maternal undernutrition promotes maternal and placental indices of oxidative stress, effects that can be prevented by maternal treatment with vitamin C in hypoxic pregnancy. While vitamin C may not be the ideal candidate of choice for therapy in pregnant women, and taking into consideration differences in ascorbic acid metabolism between rats and humans, the data do underlie that antioxidant treatment may provide a useful intervention to improve placental function and protect fetal growth in pregnancy complicated by fetal hypoxia.

DOI10.1113/jphysiol.2011.226340
Alternate JournalJ. Physiol. (Lond.)
PubMed ID22289909