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New Emerging Team on FASD: Oxidative Stress, Biomarkers & Antioxidant Therapy Leader: James F. Brien, Queen’s University Canadian Institutes of Health Research
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Biomarkers B Antioxidant Therapy A Oxidative Stress C CIHR NEW EMERGING TEAM ON FASD
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Members of NET on FASD Alan D. Bocking, obstetrics and maternal-fetal physiology, University of Toronto; James F. Brien, basic developmental pharmacology & toxicology, Queen’s University; Gideon Koren, pediatrics and clinical pharmacology & toxicology, Hospital for Sick Children, Toronto; Stephen G. Matthews, developmental neuro-endocrinology, University of Toronto; James N. Reynolds, developmental neuroscience, Queen’s University; Joanne Rovet, developmental neuropsychology, Hospital for Sick Children; Wendy J. Ungar, health economics and population health, Hospital for Sick Children.
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RESEARCH OBJECTIVES A.To test the hypothesis that oxidative stress is an important mechanism of the brain injury of FASD; B.To identify and validate reliable biomarkers for fetal ethanol exposure at critical periods of vulnerability during gestation and for the magnitude of fetal ethanol exposure; C.To discover and develop innovative antioxidant treatment strategies for preventing or attenuating ethanol-induced oxidative stress in fetal life and decreasing its impact on brain function in postnatal life.
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Coronal Section of the Brain
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RESEARCH OBJECTIVES A.To test the hypothesis that oxidative stress is an important mechanism of the brain injury of FASD; B.To identify and validate reliable biomarkers for fetal ethanol exposure at critical periods of vulnerability during gestation and for the magnitude of fetal ethanol exposure; C.To discover and develop innovative antioxidant treatment strategies for preventing or attenuating ethanol-induced oxidative stress in fetal life and decreasing its impact on brain function in postnatal life.
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OBJECTIVE A To determine whether oxidative stress is a mechanism of the brain injury of FASD. Definition of Oxidative Stress Oxygen radicals: highly reactive molecules generated during cell metabolism. Cell production of O 2 radicals Cell degradation of O 2 radicals Overabundance of O 2 radicals/Oxidative Stress
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Proposed Mechanism of Brain Injury of FASD Maternal Ingestion of Ethanol Fetal Brain Exposure to Ethanol Damage to Key Cell Molecules (DNA, Proteins, Membrane Phospholipids) Neuronal Cell Death Oxidative Stress / Increased Reactive Oxygen Species H 2 O 2 O 2 – OH Brain Injury of FASD
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Measures of Oxidative Stress 1. Glutathione (GSH): Intracellular GSH localized primarily in mitochondria and cytoplasm. 2. F 2 -Isoprostanes: Prostaglandin F 2 -like compounds. Formed in vivo by nonenzymatic free radical- induced peroxidation of arachidonic acid. Specific and stable products of lipid peroxidation. 8-iso-Prostaglandin F 2
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HIPPOCAMPUS Ethanol Offspring Control Offspring
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Experimental Animal Study Design Timed Pregnant Guinea Pigs EthanolIsocaloric-Sucrose/Water (4g/kg MBW/day) Pair-Feeding Term Fetus (GD 65) [GSH] in mitochondria and cytoplasm [8-iso-PGF 2 ] in homogenate Hippocampus
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Fetal Hippocampus
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8-iso-PGF2
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G. Weaver, University of Colorado at Denver
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Modified from J.E. Dawson and L.M Winn Apoptosis (Programmed Cell Death) and Caspase-3
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CYTOCHROME C (FETAL HIPPOCAMPUS) EthanolSucrose
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ETHANOL SUCROSE WATER ACTIVATED CASPASE-3 (FETAL HIPPOCAMPUS)
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SUMMARY Chronic ethanol exposure produces in the fetal hippocampus: depletion of mitochondrial [GSH]; mitochondrial cytochrome c leakage into cytoplasm; increase in caspase-3 enzymatic activity; no change in [8-iso-PGF 2 ].
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Disruption of the mitochondria and consequent apoptosis play key roles in the mechanism of the brain injury of FASD involving the hippocampus. CONCLUSION
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RESEARCH OBJECTIVES A.To test the hypothesis that oxidative stress is an important mechanism of the brain injury of FASD; B.To identify and validate reliable biomarkers for fetal ethanol exposure at critical periods of vulnerability during gestation and for the magnitude of fetal ethanol exposure; C.To discover and develop innovative antioxidant treatment strategies for preventing or attenuating ethanol-induced oxidative stress in fetal life and decreasing its impact on brain function in postnatal life.
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Individual [FAEE] in meconium of term fetal offspring of the ethanol and isocaloric-sucrose/pair-fed groups
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Total [FAEEs] in meconium of term fetal offspring of the ethanol, isocaloric-sucrose/pair-fed and water groups
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RESEARCH OBJECTIVES A.To test the hypothesis that oxidative stress is an important mechanism of the brain injury of FASD; B.To identify and validate reliable biomarkers for fetal ethanol exposure at critical periods of vulnerability during gestation and for the magnitude of fetal ethanol exposure; C.To discover and develop innovative antioxidant treatment strategies for preventing or attenuating ethanol-induced oxidative stress in fetal life and decreasing its impact on brain function in postnatal life.
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Rationale for Vitamin C + Vitamin E Study In women at increased risk of pre-eclampsia, pharmacological doses of vitamin C (1000 mg/day) and vitamin E (400 IU natural-source/day) starting at 16-22 weeks’ gestation and continued throughout the second half of pregnancy: decreased the occurrence of pre-eclampsia. were apparently safe with no obvious adverse fetal effects. L.C. Chappell et al., Lancet (1999).
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Ethanol Vitamins C + EVehicleVitamins C + EVehicle Nutritional Control Chronic Treatment Regimen (term, about GD 68; range, GD 66-70): Daily oral administration of vitamins C (250mg) + E (100mg) OR vehicle (milk/cream, 0/1, v/v). Two hours later, Oral administration of 4g ethanol/kg maternal body weight OR isocaloric-sucrose/pair-feeding for five consecutive days, followed by no treatment for two days, each week. PD 0: Litters (n=3-4 littermates) born by spontaneous vaginal delivery. One littermate euthanized and brain weight determined. PD 45 (range, PD 43-47): Morris water-maze task for spatial learning and memory. Moving-platform paradigm with location of hidden platform changed to a new quadrant every second day; “new locations” versus “old locations” over eight consecutive days. Daily testing consisted of two blocks of two trials each, with 5-min period between each block. Chronic Treatment Regimen: Daily oral administration of vitamins C (250mg) + E (100mg) OR vehicle (milk/cream). Two hours later, Oral administration of 4g ethanol/kg maternal body weight OR isocaloric-sucrose/pair-feeding for five consecutive days, followed by no treatment for two days, each week. PD 45: Morris water-maze task for spatial learning and memory. Ethanol Vitamins C + EVehicleVitamins C + EVehicle Nutritional Control Ethanol Vitamins C + EVehicleVitamins C + EVehicle Nutritional Control Ethanol Vitamins C + EVehicleVitamins C + EVehicle Nutritional Control Ethanol Vitamins C + E VehicleVitamins C + EVehicle Nutritional Control
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MORRIS WATER MAZE
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Figure 1: PD0 brain and hippocampal weights. Ethanol decreased brain weight compared with control; Vitamin C plus E treatment protected hippocampal weight in ethanol offspring. E = Ethanol; S = Sucrose Nutritional Control; Vit = Vitamins C + E; Veh = Vehicle Group means with different letters are statistically different (p < 0.05) Figure 1: PD0 brain and hippocampal weights. Ethanol decreased brain weight compared with control; Vitamin C plus E treatment protected hippocampal weight in ethanol offspring. E = Ethanol; S = Sucrose Nutritional Control; Vit = Vitamins C + E; Veh = Vehicle Group means with different letters are statistically different (p < 0.05) Figure 1: PD0 brain and hippocampal weights. Ethanol decreased brain weight compared with control; Vitamin C plus E treatment protected hippocampal weight in ethanol offspring. E = Ethanol; S = Sucrose Nutritional Control; Vit = Vitamins C + E; Veh = Vehicle Group means with different letters are statistically different (p < 0.05) Figure 1: PD0 brain and hippocampal weights. Ethanol decreased brain weight compared with control; Vitamin C plus E treatment protected hippocampal weight in ethanol offspring. E = Ethanol; S = Sucrose Nutritional Control; Vit = Vitamins C + E; Veh = Vehicle Group means with different letters are statistically different (p < 0.05) Figure 1: PD0 brain and hippocampal weights. Ethanol decreased brain weight compared with control; Vitamin C plus E treatment protected hippocampal weight in ethanol offspring. E = Ethanol; S = Sucrose Nutritional Control; Vit = Vitamins C + E; Veh = Vehicle Group means with different letters are statistically different (p < 0.05) Figure 1: PD0 brain and hippocampal weights. Ethanol decreased brain weight compared with control; Vitamin C plus E treatment protected hippocampal weight in ethanol offspring. E = Ethanol; S = Sucrose Nutritional Control; Vit = Vitamins C + E; Veh = Vehicle Group means with different letters are statistically different (p < 0.05) Figure 1: PD0 brain and hippocampal weights. Ethanol decreased brain weight compared with control; Vitamin C plus E treatment protected hippocampal weight in ethanol offspring. E = Ethanol; S = Sucrose Nutritional Control; Vit = Vitamins C + E; Veh = Vehicle Group means with different letters are statistically different (p < 0.05) Figure 1: PD0 brain and hippocampal weights. Ethanol decreased brain weight compared with control; Vitamin C plus E treatment protected hippocampal weight in ethanol offspring. E = Ethanol; S = Sucrose Nutritional Control; Vit = Vitamins C + E; Veh = Vehicle Group means with different letters are statistically different (p < 0.05) PD0: Brain and hippocampal weights Ethanol decreased brain weight compared with control; Vitamin C plus E treatment protected hippocampal weight in ethanol offspring. Figure 1: PD0 brain and hippocampal weights. Ethanol decreased brain weight compared with control; Vitamin C plus E treatment protected hippocampal weight in ethanol offspring. E = Ethanol; S = Sucrose Nutritional Control; Vit = Vitamins C + E; Veh = Vehicle Group means with different letters are statistically different (p < 0.05) E = Ethanol; S = Sucrose Control; Vit = Vitamins C + E; Veh = Vehicle
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PD 45: Morris water maze Vitamins C + E protected against the ethanol-induced deficit in retention of new memory ( Old Locations ). Vitamins C + E produced deficits in both acquisition (New Locations) and retention (Old Locations) of new memory in control offspring. E = Ethanol; S = Sucrose Control; Vit = Vitamins C + E; Veh = Vehicle
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Chronic maternal ethanol administration: decreased brain weight in the neonate. impaired offspring performance in the Morris water-maze task, resulting in deficits in the acquisition and retention of new memory. Maternal administration of vitamins C + E: protected hippocampal weight in ethanol-exposed offspring at birth. protected ethanol-exposed offspring from deficit in retention of new memory. produced deficits in acquisition and retention of new memory in control offspring. SUMMARY
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Vitamins C + E dose studies are being conducted to determine optimal antioxidant vitamin therapy for the brain injury of FASD. CONCLUSION
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Biomarkers B Antioxidant Therapy Training D A Oxidative Stress C CIHR NEW EMERGING TEAM ON FASD PDF PhD MSc
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R. Cohen-Kerem & G. Koren, Neurotoxicol. Teratol. (2003). Ethanol- induced Oxidative Stress Mechanism
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HIPPOCAMPAL CA1 PYRAMIDAL CELL LOSS GD 62: No cell loss PD 1: 25% Cell Loss PD 5: 30% Cell Loss PD 12: 30% Cell Loss McGoey et al., 2003
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ETHANOLSUCROSEWATER CLEAVED PARP (FETAL HIPPOCAMPUS)
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PD 45: Morris water maze Ethanol and/or vitamins C + E treatment did not affect swim speed in locating the hidden platform. E = Ethanol; S = Sucrose Control; Vit = Vitamins C + E; Veh = Vehicle
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