title: Placental antioxidant enzyme status and lipid peroxidation in pregnant women with type 1 diabetes: The effect of vitamin C and E supplementation.
abstract: OBJECTIVE
  In view of the increased rates of pre-eclampsia observed in diabetic pregnancy and the lack of ex vivo data on placental biomarkers of oxidative stress in T1 diabetic pregnancy, the aim of the current investigation was to examine placental antioxidant enzyme status and lipid peroxidation in pregnant women with type 1 diabetes. A further objective of the study was to investigate the putative impact of vitamin C and E supplementation on antioxidant enzyme activity and lipid peroxidation in type 1 diabetic placentae.
  
  
  METHODS
  The current study measured levels of antioxidant enzyme [glutathione peroxidase (Gpx), glutathione reductase (Gred), superoxide dismutase (SOD) and catalase] activity and degree of lipid peroxidation (aqueous phase hydroperoxides and 8-iso-prostaglandin F2α) in matched central and peripheral samples from placentae of DAPIT (n=57) participants. Levels of vitamin C and E were assessed in placentae and cord blood.
  
  
  RESULTS
  Peripheral placentae demonstrated significant increases in Gpx and Gred activities in pre-eclamptic in comparison to non-pre-eclamptic women. Vitamin C and E supplementation had no significant effect on cord blood or placental levels of these vitamins, nor on placental antioxidant enzyme activity or degree of lipid peroxidation in comparison to placebo-supplementation.
  
  
  CONCLUSIONS
  The finding that maternal supplementation with vitamin C/E does not augment cord or placental levels of these vitamins is likely to explain the lack of effect of such supplementation on placental indices including antioxidant enzymes or markers of lipid peroxidation.
authors.affiliation: Regional Centre for Endocrinology and Diabetes, Royal Victoria Hospital, Belfast, United Kingdom.
authors.forename: Philip C
authors.initials: PC
authors.lastname: Johnston
authors.affiliation: Regional Centre for Endocrinology and Diabetes, Royal Victoria Hospital, Belfast, United Kingdom.
authors.forename: David R
authors.initials: DR
authors.lastname: McCance
authors.affiliation: Nutrition and Metabolism Group, Centre for Public Health, Queen's University, Belfast, United Kingdom.
authors.forename: Valerie A
authors.initials: VA
authors.lastname: Holmes
authors.affiliation: Nutrition and Metabolism Group, Centre for Public Health, Queen's University, Belfast, United Kingdom.
authors.forename: Ian S
authors.initials: IS
authors.lastname: Young
authors.affiliation: Nutrition and Metabolism Group, Centre for Public Health, Queen's University, Belfast, United Kingdom. Electronic address: a.mcginty@qub.ac.uk.
authors.forename: Ann
authors.initials: A
authors.lastname: McGinty
mesh_terms: D001205:Ascorbic Acid / Q000097:blood / Q000378:metabolism / Q000627:therapeutic use*; D015415:Biomarkers / Q000097:blood / Q000378:metabolism; D015331:Cohort Studies; D003922:Diabetes Mellitus, Type 1 / Q000097:blood / Q000150:complications / Q000178:diet therapy* / Q000378:metabolism; D019587:Dietary Supplements; D005260:Female; D005312:Fetal Blood; D006801:Humans; D015227:Lipid Peroxidation; D039382:Maternal Nutritional Physiological Phenomena; D009660:Northern Ireland / Q000453:epidemiology; D018384:Oxidative Stress; D010088:Oxidoreductases / Q000737:chemistry / Q000378:metabolism; D010920:Placenta / Q000201:enzymology* / Q000378:metabolism; D011225:Pre-Eclampsia / Q000453:epidemiology / Q000517:prevention & control; D011247:Pregnancy; D011254:Pregnancy in Diabetics / Q000097:blood / Q000178:diet therapy* / Q000201:enzymology / Q000378:metabolism; D018566:Pregnancy, High-Risk / Q000097:blood / Q000378:metabolism; D012306:Risk; D014810:Vitamin E / Q000097:blood / Q000378:metabolism / Q000627:therapeutic use*
chemical_list: D015415:Biomarkers; D014810:Vitamin E; D010088:Oxidoreductases; D001205:Ascorbic Acid
keywords: Antioxidant status; Lipid peroxidation; Placenta; Pre-eclampsia; Type 1 diabetes mellitus; Vitamin C and E supplementation