Maternal Iron Deficiency Worsens the Associative Learning Deficits and Hippocampal and Cerebellar Losses in a Rat Model of Fetal Alcohol Spectrum Disorders. (24th September 2015)

• Record Type: Journal Article
• Authors: Huebner, Shane M.; Tran, Tuan D.; Rufer, Echoleah S.; Crump, Peter M.; Smith, Susan M.
• Is Part Of: Alcoholism. Volume 39:Number 11(2015:Nov.)
• Page Start: 2097
• Page End: 2107
• Publication Date: 2015-09-24
• Subjects: Fetal Alcohol Spectrum Disorders -- Iron Deficiency -- Hippocampus -- Cerebellum -- Stereology -- Eyeblink Conditioning; Alcoholism -- Periodicals; Alcoholism -- Periodicals; Alcoolisme; Electronic journals; Périodique électronique (Descripteur de forme); Ressource Internet (Descripteur de forme); 616.861005
• DOI: 10.1111/acer.12876
• Languages: English
• ISSNs: 0145-6008

Abstract

Abstract : Background: Gestational alcohol exposure causes lifelong physical and neurocognitive deficits collectively referred to as fetal alcohol spectrum disorders (FASDs). Micronutrient deficiencies are common in pregnancies of alcohol‐abusing women. Here we show the most common micronutrient deficiency of pregnancy—iron deficiency without anemia—significantly worsens neurocognitive outcomes following perinatal alcohol exposure. Methods: Pregnant rats were fed iron‐deficient (ID) or iron‐sufficient diets from gestational day 13 to postnatal day (P) 7. Pups received alcohol (0, 3.5, 5.0 g/kg) from P 4 to P 9, targeting the brain growth spurt. At P 32, learning was assessed using delay or trace eyeblink classical conditioning (ECC). Cerebellar interpositus nucleus (IPN) and hippocampal CA1 cellularity was quantified using unbiased stereology. Results: Global analysis of variance revealed that ID and alcohol separately and significantly reduced ECC learning with respect to amplitude ( p s ≤ 0.001) and conditioned response [CR] percentage ( p s ≤ 0.001). Iron and alcohol interacted to reduce CR percentage in the trace ECC task ( p = 0.013). Both ID and alcohol significantly reduced IPN ( p s < 0.001) and CA1 cellularity ( p s < 0.005). CR amplitude correlated with IPN cellularity (delay: r = 0.871, trace: r = 0.703, p s < 0.001) and CA1 cellularity (delay: r = 0.792, trace: r = 0.846, p s < 0.001) across both tasks. The learning impairments persisted even though the offsprings' iron status had normalized. Conclusions: Supporting our previous work, gestational ID exacerbates the associative learning deficits in this rat model of FASD. This is strongly associated with cellular reductions within the ECC neurocircuitry. Significant learning impairments in FASD could be the consequence, in part, of pregnancies in which the mother was also iron inadequate.