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New Emerging Team on Fetal Alcohol Syndrome:Oxidative Stress, Biomarkers and
Antioxidant Therapy
New Emerging Team on Fetal Alcohol Syndrome:Oxidative Stress, Biomarkers and
Antioxidant Therapy
Leader: James F. Brien, Queen’s UniversityLeader: James F. Brien, Queen’s University
Fetal Alcohol SyndromeFetal Alcohol Syndrome
• Growth deficiency• Facial characteristics• Brain injury (structural and functional)
Alcohol-Related Neurodevelopmental Disorder
Alcohol-Related Neurodevelopmental Disorder
• Brain injury (structural and functional)
Fetal Alcohol Spectrum DisorderFetal Alcohol Spectrum Disorder
• All-inclusive term for the different manifestations of alcohol-induced birth defects (teratogenic effects).
Coronal Section of the BrainCoronal Section of the Brain
Critical Periods of Human DevelopmentCritical Periods of Human Development
K.L. Moore. The Developing Human, Clinically Oriented Embryology (1988).
Biomarkers
B
Antioxidant Therapy
AOxidative Stress
C
CIHR NEW EMERGING TEAM ON FASCIHR NEW EMERGING TEAM ON FAS
Members of NET on FASMembers of NET on FASAlan 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
Research ObjectivesResearch Objectives
A. To test the hypothesis that oxidative stress is an important mechanism of the brain injury of FAS.
B. To identify and validate reliable biomarkers for fetal alcohol exposure at critical periods of vulnerability
during gestation and for the magnitude of fetal alcohol exposure.
C. To discover and develop innovative antioxidant treatment strategies for preventing or attenuating the brain injury of FAS.
Objective AObjective ATo determine whether oxidative stress is a mechanism of
the brain injury of FAS.
Definition of Oxidative StressDefinition of Oxidative StressOxygen radicals: highly reactive molecules generated
during cell metabolism.
Cell production
of O2 radicals
Cell degradation
of O2 radicals
Overabundance of O2 radicals/Oxidative Stress
Proposed Mechanism of Brain Injury of FASProposed Mechanism of Brain Injury of FAS
Maternal Ingestion of Alcohol
Fetal Brain Exposure to Alcohol
Damage to Key Cell Macromolecules(DNA, Proteins, Membrane Phospholipids)
Fetal Brain Nerve Cell Death
Oxidative Stress / Increased Reactive Oxygen Species
H2O2 O2– OH
Brain Injury of FAS
Depletion of Glutathione(a peptide that protects against Oxidative Stress)
G. Weaver, University of Colorado at Denver
Measures of Oxidative StressMeasures of Oxidative Stress
Products of chemical reaction:reactive oxygen + membrane
species phospholipids
3. Neuroimaging of brain:magnetic resonance imaging - structural changes.magnetic resonance spectroscopy - oxidative stress.
2. F2-isoprostanes:
lipid peroxidation
8-iso-Prostaglandin F2
1. Glutathione (GSH):Small intracellular protein (peptide) localized in mitochondria (energy -producing organelles) and other sites within the cell.
Investigation of Occurrence of Oxidative StressInvestigation of Occurrence of Oxidative Stress
1. Guinea pig study (fetus and neonate) of key brain areas: GSH and 8-iso-PGF2.
Following chronic prenatal alcohol exposure:• Decreased mitochondrial GSH content in
fetal hippocampus (learning and memory).• No change in 8-iso-PGF2 content in fetal or neonatal
hippocampus or other key brain areas.
2. Study of FAS children: neuroimaging of brain for evidence of oxidative stress and relationship to structural changes and cognitive deficits.
Objective BObjective B
To identify biochemical markers in meconium (first stool passed by neonate) as measure of: gestational time and magnitude of fetal alcohol exposure resulting from maternal drinking.
Fatty acid ethyl esters (FAEEs)(family of chemical compounds)
Products of enzymatic reaction:Fatty acids + Ethanol in in body alcoholic beverages
FAEEs
Investigation of FAEEs as Biomarkers ofFetal Alcohol Exposure
Investigation of FAEEs as Biomarkers ofFetal Alcohol Exposure
1. Pregnant guinea pig study:identification of members of FAEEs family that constitute biomarkers of gestational time and magnitude of fetal alcohol exposure.
• FAEEs measurable in meconium of term fetus following chronic prenatal alcohol exposure.
• No measurable FAEEs in meconium of non-alcohol-exposed fetus.
• Five different FAEEs identified for chronic prenatal alcohol exposure; ethyl linoleate most common.
Investigation of FAEEs as Biomarkers ofFetal Alcohol Exposure
Investigation of FAEEs as Biomarkers ofFetal Alcohol Exposure
2. Human meconium clinical study:elucidation of prevalence of alcohol consumption by pregnant women in Canada.
• 6x Increase in FAEEs in neonatal meconium for heavy prenatal alcohol exposure compared with control.
• Seven different FAEEs identified for prenatal alcohol exposure; four FAEEs most common, including ethyl linoleate.
Objective CObjective C
To determine therapeutic efficacy and cost-effectiveness of antioxidant therapy for prevention/attenuation of brain injury of FAS.
Vitamin C + Vitamin E(pharmacological doses)
Investigation of Antioxidant TherapyInvestigation of Antioxidant Therapy
1. Guinea pig study:evaluation of efficacy of vitamin C + vitamin E to prevent/attenuate brain injury produced by chronic fetal alcohol exposure.
2. Human studies:• evaluation of therapeutic efficacy and
cost-effectiveness of vitamin C + vitamin E in preventing/attenuating brain injury of FAS.
• investigation of determinants of recruitment and retention of pregnant alcohol-using women in preventative treatment.
Biomarkers
B
Antioxidant Therapy
Training
D
AOxidative Stress
C
CIHR NEW EMERGING TEAM ON FASCIHR NEW EMERGING TEAM ON FAS
2 PDF
3 PhD
3 MSc