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FETAL ALCOHOL SPECTRUM DISORDERS : Current Science & Research Trends. May 14, 2009. Feng C. Zhou, Ph.D. Professor of Anatomy, Cell Biology, Neuroscience, & Psychology Indiana University School of Medicine Stark Neuroscience Research Institute. Fetal Alcohol Spectrum Disorder Study Group.
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FETAL ALCOHOL SPECTRUM DISORDERS: Current Science & Research Trends May 14, 2009 Feng C. Zhou, Ph.D. Professor of Anatomy, Cell Biology, Neuroscience, & Psychology Indiana University School of Medicine Stark Neuroscience Research Institute
Fetal Alcohol Spectrum Disorder Study Group http://www.rsoa.org/fas.html • The FASDSG has a membership of approximately 425 clinicians and researchers. • The binding interests of our members are the desire to fully understand the etiology of fetal alcohol syndrome (FAS), describe the characteristics of fetal alcohol spectrum disorders at multiple levels, and devise ways to improve the lives of children, adolescents, and adults with FAS and other alcohol-related disabilities.
Current Science & Research Trend An Update • Teratogenic effect • Diagnosis & Biomarkers • Prevention-intervention & Treatment
Teratogenic Effects • Neurodevelopmental deficit: brain • Craniofacial deformities • Malformed organs including the heart and the eyes • Growth and developmental retardation • Cognitive and behavioral abnormalities Differentiation (2007) 75:393–403
Possible FASD Symptoms: • Neurodevelopmental deficit: • small brain; faulty arrangement of brain cells; mental retardation -- learning disabilities; short attention span; irritability in infancy; hyperactivity in childhood; poor coordination, executive deficit. • Growth deficiencies: small head, body size, • slower development and failure to catch up. • Facial dysmorphology: small eye openings; • drooping eyelids; nearsightedness; short upturned nose; sunken nasal bridge; flat or absent philtrum ; thin upper lip; opening in roof of mouth; small jaw. • Skeletal deformities: deformed ribs and sternum; • curved spine; bent, fused, webbed, • or missing fingers or toes; limited movement of joints. • Organ deformities: heart defects; heart murmurs; genital malformations; kidney and urinary defects.
MRI Magnetic resonance imaging Alcohol Clin Exp Res, Vol 32, No 10, 2008: pp 1732–1740 Caudate Nucleus Putamen Globus Pallidus Thalamus
Mouse Embryos MRI Alcohol Clin Exp Res, Vol 33, No 4, 2009: pp 1–11
Animal model of Incompleted Neural Tube Closure Ventral view Coronal section
Gray matter asymmetry American Journal of Medical Genetics Part C (Semin. Med. Genet.) 127C:35–41 (2004)
Cortical Thickness Cerebral Cortex January 2008;18:136-144
Verbal activation Control Subjects Alcohol Exposed Alcohol-exposed subjects display greater activation relative to TD subjects suggest that frontal-parietal processing during verbal WM is less efficient in alcohol-exposed individuals.
Midline Abnormality-- Corpus callosum FAS FAS Normal Mattson et al, 1994
DTI Diffuse tensor imaging R L Body CC SLF SFO IFO Alcohol Clin Exp Res, Vol 32, No 10, 2008: pp 1732–1740 UF Splenium CC Cingulum CST ILF Genu CC
Corpus callosum American Journal of Medical Genetics Part C (Semin. Med. Genet.) 127C:35–41 (2004)
Eye Defect detected in Animal model: mouse Alcohol Clin Exp Res, Vol 33, No 4, 2009: pp 1–11
Eye Defect detected in Animal model: Zebrafish Differentiation (2007) 75:393–403
Brain chemistry • Glutamate and its receptor NMDA • GABA • Serotonin (5-HT) Neuronal Circuitry & Function • Fronto-Prietal circuitry: executive & sensory motor function, IQ • Hippocampal circuitry: learning, memory • Cerebellum circuitry: reflect, motor coordination • Limbic circuitry: emotion, EQ
5-HT neurons at E11 PF Alc
A Hypothesis: 5-HT Signals Cortical Differentiation Density of 5-HT fibers
Diagnosis • Maternal: Drinking history, Biomarkers (how about paternal?) • Prenatal: Ultrasound • New Born: Biochemical Biomarker • Children: Facial Dysmorphology, IQ, Learning disability…
Diagnosis: Facial Dysmorphology Am Fam Physician 2005;72:279-82, 285. Epicanthal folds Flat nasal bridge Small palpebral fissures “Railroad track” ears Upturned nose Smooth philtrum Thin upper lip
Facial Dysmorphology Alcohol Clin Exp Res, Vol 33, No 4, 2009: pp 1–11
Characteristic facial features in children of different ethnicities Am Fam Physician 2005;72:279-82, 285.
The Lip/Philtrum Guide American Journal of Medical Genetics 140A:137–143 (2006)
Facial measurement for diagnosis Med Eng Phys 29 (2007) 4, pp. 459-464
Anthropometry analysis Moore et al, 2006
Computational Facial Diagnosis: Future Telemedicine OrthodCraniofac Res 2008;11:162–171
FAEE as a biomarker for in utero alcohol exposure Fatty acid ethyl esters are a product of non-oxidative metabolism of ethanol, persisting in blood for >24 hours after significant alcohol consumption. Any FAEE detected in neonatal biological matrices are likely produced by the fetus from ethanol transferred to and metabolized by the fetus. Neurosci Biobehav Rev. 2007;31(2):254-60
Formation of FAEEs ANN IST SUPER SANITÀ 2006 | VOL. 42, NO. 1: 39-45 CMAJ • NOV. 25, 2003; 169 (11)
Meconium Screening • Meconium is a matrix unique to the developing fetus that is commonly used in neonatal drug screening. • FAEEs have the ability to accumulate in meconium. • Substances begin to accumulate in meconium from the 13th week of human gestation, allowing for analysis in the 2nd and 3rd trimesters. • FAEEs can be found independent of maternal alcohol consumption because ethanol is a common byproduct of metabolism. • A total FAEE accumulation of 2 nmol/g of meconium is the cutoff for distinguishing neonates of non-drinking mothers from offspring of heavy drinkers
FAEE Hair Testing • Neonatal hair collection can occur up to 3 months after birth; meconium is only available the first 2-3 days of life. • Neonatal hair begins its growth at approximately the third or fourth week of fetal life. Consequently, any exposures within the last trimester of pregnancy may be theoretically found in neonatal hair after birth. • FAEE have prolonged stability in the hair matrix. Neurosci Biobehav Rev. 2007;31(2):254-60
High throughput screening of Biomarkers • Gene array: Gene profile • Proteomics: Protein profile • Metabolomics: Metabolite profile • Epigenetics: epigenetic profile
global gene expression patterns Understand how transcription factors work cooperatively transcriptional machinery Identify Alcohol induced gene alteration : Gene Chip and informatics • From the global gene expression patterns (microarray data) to: • Identify genes altered by alcohol exposure • Identify transcription-factor binding sites (TFBS) • Evaluate the functions of predicted TFBS in response to certain biological treatment Gene chip & Informatics
Prevention of FASD • Best policy: The only guaranteed prevention of FASD is abstinence from alcohol during pregnancy. • Education and Awareness: Interventions aimed at ensuring that all community members understand the adverse consequences of drinking alcohol during pregnancy. • Targeting High Risk: Selective prevention interventions targeting women at higher risk of having an infant with a fetal alcohol spectrum disorder because they drink alcohol and are in the reproductive age range. Birth Defects Research (Part A) 85:8292 (2009)
Prevention (cont’d) • Prevention interventions targeting women who drink heavily while pregnant or at risk for pregnancy, or women who have given birth to a child with FAS. • Use of a brief intervention technique about alcohol use (10- to 15-minute sessions of counseling) among pregnant women or women of childbearing age has been shown to be effective. • In nonpregnant women, a brief motivational intervention was shown to decrease the risk of exposure to alcohol during pregnancy through decreasing risky drinking Birth Defects Research (Part A) 85:8292 (2009)
Treatment-prevention: Nutritional supplements Choline: In a rat model, Choline supplementation in postnatal rats was shown to reduce alcohol-related learning impairments, and choline’s therapeutic window may be quite large. Brain Res. 2008 Oct 27;1237:91-100 Folic Acid: Prevention of Neural tube defect
Treatment in animal studies: Drugs approved for other uses • Glutamate antagonist • Another study in ewes showed that acid-sensitive channel inhibition in TWIK-related acid-sensitive potassium channels (TASKs 1&3) prevented FASD fetal cerebellar Purkinje cell loss. Am J Physiol Regul Integr Comp Physiol 295: R596–R603, 2008.
Chow PF Alc Alc+SAL Chow+SAL Treatment in animal studies: Neurotrophic peptides
Alcohol and Neural Stem Cells • Neural stem cells exist throughout life span. • Neural stem cells, now believed, contribute to health and sickness. • Prenatal alcohol exposure reduce neural stem cells.
Treatment in animal studies: : Enriched environment • Most treatment methods focus on improving the behavioral and functional deficits seen in children with FASD, like learning disabilities, working memory deficits, attention deficits, and social deficits.