Developmental changes in antioxidant enzymatic defences against oxidative stress in sheep placentomes

Catherine Garrel, Paul Alfred Francois Fowler, Kais H. Al-Gubory

Research output: Contribution to journalArticle

33 Citations (Scopus)

Abstract

Early pregnancy is susceptible to oxidative stress, and thus characterisation of antioxidant systems and pro- and antiapoptotic pathways would improve understanding of placental development and function. We aimed, therefore, to determine the activities of the antioxidant enzymes, copper/zinc-superoxide dismutase (SOD1), manganese-SOD (SOD2), catalase (CAT), glutathione (GSH) peroxidase (GPX) and GSH reductase (GSR); and to quantify the expression of BAX and MCL1 proteins in relation to the developmental changes in antioxidant defences in sheep placentomes sampled on days 35, 55 and 80 of pregnancy. Placentome progesterone content was analyzed to determine steroidogenic capacity. Malondialdehyde (MDA) and protein carbonyl were quantified in placentomes as biomarkers of lipid peroxidation and protein damage respectively. Placentome tissues demonstrated significantly increased content of progesterone and MDA at day 80 of pregnancy and protein carbonyl as early as day 50 of pregnancy. Progesterone and MDA contents were not different between days 35 and 55 of pregnancy. While SOD1 and CAT activities did not alter significantly, SOD2 activity decreased from days 35 to 55. GPX activity increased from days 35 to 55 and increased further to day 80 of pregnancy. GSR activity increased from days 35 to 55 of pregnancy. BAX protein expression decreased, while MCL1 increased from days 35 to 55 and 80 of pregnancy. The increased GPX activity was associated with a decrease in the BAX/MCL1 protein expression ratio. Changes in the antioxidant enzymatic defences could be a part of placentome adaptation to reactive oxygen species-induced oxidative stress at specific early developmental stages of pregnancy. Journal of Endocrinology (2010) 205, 107-116

Original languageEnglish
Pages (from-to)107-116
Number of pages10
JournalJournal of Endocrinology
Volume205
Issue number1
Early online date22 Jan 2010
DOIs
Publication statusPublished - 1 Apr 2010

Keywords

  • glutathione-dependent enzymes
  • messenger-RNA expression
  • superoxide-dismutase
  • lipid-peroxidation
  • reactive oxgyen
  • corpus-luteum
  • progesterone concentrations
  • ovine placenta
  • free-radicals
  • in-vivo

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