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Milbocker KA, Smith IF, Brengel EK, LeBlanc GL, Roth TL, Klintsova AY. Exercise in Adolescence Enhances Callosal White Matter Refinement in the Female Brain in a Rat Model of Fetal Alcohol Spectrum Disorders. Cells 2023; 12:cells12070975. [PMID: 37048047 PMCID: PMC10092997 DOI: 10.3390/cells12070975] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Revised: 03/15/2023] [Accepted: 03/20/2023] [Indexed: 04/14/2023] Open
Abstract
A total of 1 in 20 infants born annually are exposed to alcohol prenatally, which disrupts neurodevelopment and results in several disorders categorized under the umbrella term Fetal Alcohol Spectrum Disorders (FASD). Children and adolescents affected by FASD exhibit delayed maturation of cerebral white matter, which contributes to deficits in executive function, visuospatial processing, sensory integration, and interhemispheric communication. Research using animal models of FASD have uncovered that oligoglia proliferation, differentiation, and survival are vulnerable to alcohol teratogenesis in the male brain due in part to the activation of the neuroimmune system during gestation and infancy. A comprehensive investigation of prenatal alcohol exposure on white matter development in the female brain is limited. This study demonstrated that the number of mature oligodendrocytes and the production of myelin basic protein were reduced first in the female corpus callosum following alcohol exposure in a rat model of FASD. Analysis of myelin-related genes confirmed that myelination occurs earlier in the female corpus callosum compared to their counterparts, irrespective of postnatal treatment. Moreover, dysregulated oligodendrocyte number and myelin basic protein production was observed in the male and female FASD brain in adolescence. Targeted interventions that support white matter development in FASD-affected youth are nonexistent. The capacity for an adolescent exercise intervention to upregulate corpus callosum myelination was evaluated: we discovered that volunteer exercise increases the number of mature oligodendrocytes in alcohol-exposed female rats. This study provides critical evidence that oligoglia differentiation is difficult but not impossible to induce in the female FASD brain in adolescence following a behavioral intervention.
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Affiliation(s)
- Katrina A Milbocker
- Department of Psychological and Brain Sciences, University of Delaware, Newark, DE 19716, USA
| | - Ian F Smith
- Department of Psychological and Brain Sciences, University of Delaware, Newark, DE 19716, USA
| | - Eric K Brengel
- Department of Psychological and Brain Sciences, University of Delaware, Newark, DE 19716, USA
| | - Gillian L LeBlanc
- Department of Psychological and Brain Sciences, University of Delaware, Newark, DE 19716, USA
| | - Tania L Roth
- Department of Psychological and Brain Sciences, University of Delaware, Newark, DE 19716, USA
| | - Anna Y Klintsova
- Department of Psychological and Brain Sciences, University of Delaware, Newark, DE 19716, USA
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2
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Smiley JF, Bleiwas C, Marino BM, Vaddi P, Canals-Baker S, Wilson DA, Saito M. Estimates of total neuron number show that neonatal ethanol causes immediate and lasting neuron loss in cortical and subcortical areas. Front Neurosci 2023; 17:1186529. [PMID: 37205048 PMCID: PMC10185770 DOI: 10.3389/fnins.2023.1186529] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Accepted: 04/13/2023] [Indexed: 05/21/2023] Open
Abstract
In neonatal brain development there is a period of normal apoptotic cell death that regulates adult neuron number. At approximately the same period, ethanol exposure can cause a dramatic spike in apoptotic cell death. While ethanol-induced apoptosis has been shown to reduce adult neuron number, questions remain about the regional selectivity of the ethanol effect, and whether the brain might have some capacity to overcome the initial neuron loss. The present study used stereological cell counting to compare cumulative neuron loss 8 h after postnatal day 7 (P7) ethanol treatment to that of animals left to mature to adulthood (P70). Across several brain regions we found that the reduction of total neuron number after 8 h was as large as that of adult animals. Comparison between regions revealed that some areas are more vulnerable, with neuron loss in the anterior thalamic nuclei > the medial septum/vertical diagonal band, dorsal subiculum, and dorsal lateral geniculate nucleus > the mammillary bodies and cingulate cortex > whole neocortex. In contrast to estimates of total neuron number, estimates of apoptotic cell number in Nissl-stained sections at 8 h after ethanol treatment provided a less reliable predictor of adult neuron loss. The findings show that ethanol-induced neonatal apoptosis often causes immediate neuron deficits that persist in adulthood, and furthermore suggests that the brain may have limited capacity to compensate for ethanol-induced neuron loss.
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Affiliation(s)
- John F. Smiley
- Nathan Kline Institute for Psychiatric Research, Orangeburg, NY, United States
- Department of Psychiatry, School of Medicine, New York University, New York, NY, United States
- *Correspondence: John F. Smiley,
| | - Cynthia Bleiwas
- Nathan Kline Institute for Psychiatric Research, Orangeburg, NY, United States
| | - Brandon M. Marino
- Nathan Kline Institute for Psychiatric Research, Orangeburg, NY, United States
| | - Prerana Vaddi
- Nathan Kline Institute for Psychiatric Research, Orangeburg, NY, United States
| | | | - Donald A. Wilson
- Nathan Kline Institute for Psychiatric Research, Orangeburg, NY, United States
- Department of Child and Adolescent Psychiatry, School of Medicine, New York University, New York, NY, United States
- Department of Neuroscience and Physiology, School of Medicine, New York University, New York, NY, United States
| | - Mariko Saito
- Nathan Kline Institute for Psychiatric Research, Orangeburg, NY, United States
- Department of Psychiatry, School of Medicine, New York University, New York, NY, United States
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3
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Smiley JF, Bleiwas C, Canals-Baker S, Williams SZ, Sears R, Teixeira CM, Wilson DA, Saito M. Neonatal ethanol causes profound reduction of cholinergic cell number in the basal forebrain of adult animals. Alcohol 2021; 97:1-11. [PMID: 34464696 DOI: 10.1016/j.alcohol.2021.08.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Revised: 05/24/2021] [Accepted: 08/12/2021] [Indexed: 11/26/2022]
Abstract
In animal models that mimic human third-trimester fetal development, ethanol causes substantial cellular apoptosis in the brain, but for most brain structures, the extent of permanent neuron loss that persists into adulthood is unknown. We injected ethanol into C57BL/6J mouse pups at postnatal day 7 (P7) to model human late-gestation ethanol toxicity, and then used stereological methods to investigate adult cell numbers in several subcortical neurotransmitter systems that project extensively in the forebrain to regulate arousal states. Ethanol treatment caused especially large reductions (34-42%) in the cholinergic cells of the basal forebrain, including cholinergic cells in the medial septal/vertical diagonal band nuclei (Ch1/Ch2) and in the horizontal diagonal band/substantia innominata/nucleus basalis nuclei (Ch3/Ch4). Cell loss was also present in non-cholinergic basal forebrain cells, as demonstrated by 34% reduction of parvalbumin-immunolabeled GABA cells and 25% reduction of total Nissl-stained neurons in the Ch1/Ch2 region. In contrast, cholinergic cells in the striatum were reduced only 12% by ethanol, and those of the brainstem pedunculopontine/lateral dorsal tegmental nuclei (Ch5/Ch6) were not significantly reduced. Similarly, ethanol did not significantly reduce dopamine cells of the ventral tegmental area/substantia nigra or serotonin cells in the dorsal raphe nucleus. Orexin (hypocretin) cells in the hypothalamus showed a modest reduction (14%). Our findings indicate that the basal forebrain is especially vulnerable to alcohol exposure in the late gestational period. Reduction of cholinergic and GABAergic projection neurons from the basal forebrain that regulate forebrain arousal may contribute to the behavioral and cognitive deficits associated with neonatal ethanol exposure.
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4
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Niedzwiedz-Massey VM, Douglas JC, Rafferty T, Wight PA, Kane CJM, Drew PD. Ethanol modulation of hippocampal neuroinflammation, myelination, and neurodevelopment in a postnatal mouse model of fetal alcohol spectrum disorders. Neurotoxicol Teratol 2021; 87:107015. [PMID: 34256161 PMCID: PMC8440486 DOI: 10.1016/j.ntt.2021.107015] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Revised: 06/24/2021] [Accepted: 07/08/2021] [Indexed: 01/15/2023]
Abstract
Fetal alcohol spectrum disorders (FASD) are alarmingly common and result in significant personal and societal loss. Neuropathology of the hippocampus is common in FASD leading to aberrant cognitive function. In the current study, we evaluated the effects of ethanol on the expression of a targeted set of molecules involved in neuroinflammation, myelination, neurotransmission, and neuron function in the developing hippocampus in a postnatal model of FASD. Mice were treated with ethanol from P4-P9, hippocampi were isolated 24 h after the final treatment at P10, and mRNA levels were quantitated by qRT-PCR. We evaluated the effects of ethanol on both pro-inflammatory and anti-inflammatory molecules in the hippocampus and identified novel mechanisms by which ethanol induces neuroinflammation. We further demonstrated that ethanol decreased expression of molecules associated with mature oligodendrocytes and greatly diminished expression of a lacZ reporter driven by the first half of the myelin proteolipid protein (PLP) gene (PLP1). In addition, ethanol caused a decrease in genes expressed in oligodendrocyte progenitor cells (OPCs). Together, these studies suggest ethanol may modulate pathogenesis in the developing hippocampus through effects on cells of the oligodendrocyte lineage, resulting in altered oligodendrogenesis and myelination. We also observed differential expression of molecules important in synaptic plasticity, neurogenesis, and neurotransmission. Collectively, the molecules evaluated in these studies may play a role in ethanol-induced pathology in the developing hippocampus and contribute to cognitive impairment associated with FASD. A better understanding of these molecules and their effects on the developing hippocampus may lead to novel treatment strategies for FASD.
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Affiliation(s)
- Victoria M Niedzwiedz-Massey
- Department of Neurobiology and Developmental Sciences, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - James C Douglas
- Department of Neurobiology and Developmental Sciences, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - Tonya Rafferty
- Department of Neurobiology and Developmental Sciences, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - Patricia A Wight
- Department of Physiology and Cell Biology, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - Cynthia J M Kane
- Department of Neurobiology and Developmental Sciences, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - Paul D Drew
- Department of Neurobiology and Developmental Sciences, University of Arkansas for Medical Sciences, Little Rock, AR, USA; Department of Neurology, University of Arkansas for Medical Sciences, Little Rock, AR, USA.
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5
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Savage LM, Nunes PT, Gursky ZH, Milbocker KA, Klintsova AY. Midline Thalamic Damage Associated with Alcohol-Use Disorders: Disruption of Distinct Thalamocortical Pathways and Function. Neuropsychol Rev 2021; 31:447-471. [PMID: 32789537 PMCID: PMC7878584 DOI: 10.1007/s11065-020-09450-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Accepted: 07/30/2020] [Indexed: 02/07/2023]
Abstract
The thalamus, a significant part of the diencephalon, is a symmetrical and bilateral central brain structure. The thalamus is subdivided into three major groups of nuclei based on their function: sensorimotor nuclei (or principal/relay nuclei), limbic nuclei and nuclei bridging these two domains. Anatomically, nuclei within the thalamus are described by their location, such as anterior, medial, lateral, ventral, and posterior. In this review, we summarize the role of medial and midline thalamus in cognition, ranging from learning and memory to flexible adaptation. We focus on the discoveries in animal models of alcohol-related brain damage, which identify the loss of neurons in the medial and midline thalamus as drivers of cognitive dysfunction associated with alcohol use disorders. Models of developmental ethanol exposure and models of adult alcohol-related brain damage and are compared and contrasted, and it was revealed that there are similar (anterior thalamus) and different (intralaminar [adult exposure] versus ventral midline [developmental exposure]) thalamic pathology, as well as disruptions of thalamo-hippocampal and thalamo-cortical circuits. The final part of the review summarizes approaches to recover alcohol-related brain damage and cognitive and behavioral outcomes. These approaches include pharmacological, nutritional and behavioral interventions that demonstrated the potential to mitigate alcohol-related damage. In summary, the medial/midline thalamus is a significant contributor to cognition function, which is also sensitive to alcohol-related brain damage across the life span, and plays a role in alcohol-related cognitive dysfunction.
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Affiliation(s)
- Lisa M Savage
- Developmental Ethanol Alcohol Research Center, Department of Psychology, Binghamton University, State University of New York, Binghamton, NY, 13902-6000, USA.
| | - Polliana T Nunes
- Developmental Ethanol Alcohol Research Center, Department of Psychology, Binghamton University, State University of New York, Binghamton, NY, 13902-6000, USA
| | - Zachary H Gursky
- Department of Psychological and Brain Sciences, University of Delaware, Newark, DE, USA
| | - Katrina A Milbocker
- Department of Psychological and Brain Sciences, University of Delaware, Newark, DE, USA
| | - Anna Y Klintsova
- Department of Psychological and Brain Sciences, University of Delaware, Newark, DE, USA
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6
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Dannenhoffer CA, Robertson MM, Macht VA, Mooney SM, Boettiger CA, Robinson DL. Chronic alcohol exposure during critical developmental periods differentially impacts persistence of deficits in cognitive flexibility and related circuitry. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2021; 160:117-173. [PMID: 34696872 DOI: 10.1016/bs.irn.2021.07.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Cognitive flexibility in decision making depends on prefrontal cortical function and is used by individuals to adapt to environmental changes in circumstances. Cognitive flexibility can be measured in the laboratory using a variety of discrete, translational tasks, including those that involve reversal learning and/or set-shifting ability. Distinct components of flexible behavior rely upon overlapping brain circuits, including different prefrontal substructures that have separable impacts on decision making. Cognitive flexibility is impaired after chronic alcohol exposure, particularly during development when the brain undergoes rapid maturation. This review examines how cognitive flexibility, as indexed by reversal and set-shifting tasks, is impacted by chronic alcohol exposure in adulthood, adolescent, and prenatal periods in humans and animal models. We also discuss areas for future study, including mechanisms that may contribute to the persistence of cognitive deficits after developmental alcohol exposure and the compacting consequences from exposure across multiple critical periods.
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Affiliation(s)
- C A Dannenhoffer
- Bowles Center for Alcohol Studies, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - M M Robertson
- Department of Psychology and Neuroscience, University of North Carolina, Chapel Hill, NC, United States
| | - Victoria A Macht
- Bowles Center for Alcohol Studies, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - S M Mooney
- Nutrition Research Institute and Department of Nutrition, University of North Carolina, Chapel Hill, NC, United States
| | - C A Boettiger
- Bowles Center for Alcohol Studies, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States; Department of Psychology and Neuroscience, University of North Carolina, Chapel Hill, NC, United States; Neuroscience Curriculum, University of North Carolina, Chapel Hill, NC, United States; Biomedical Research Imaging Center, University of North Carolina, Chapel Hill, NC, United States
| | - Donita L Robinson
- Bowles Center for Alcohol Studies, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States; Department of Psychiatry, University of North Carolina, Chapel Hill, NC, United States; Neuroscience Curriculum, University of North Carolina, Chapel Hill, NC, United States.
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7
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Pinson MR, Holloway KN, Douglas JC, Kane CJM, Miranda RC, Drew PD. Divergent and overlapping hippocampal and cerebellar transcriptome responses following developmental ethanol exposure during the secondary neurogenic period. Alcohol Clin Exp Res 2021; 45:1408-1423. [PMID: 34060105 PMCID: PMC8312515 DOI: 10.1111/acer.14633] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 04/16/2021] [Accepted: 05/11/2021] [Indexed: 12/24/2022]
Abstract
Background The developing hippocampus and cerebellum, unique among brain regions, exhibit a secondary surge in neurogenesis during the third trimester of pregnancy. Ethanol (EtOH) exposure during this period is results in a loss of tissue volume and associated neurobehavioral deficits. However, mechanisms that link EtOH exposure to teratology in these regions are not well understood. We therefore analyzed transcriptomic adaptations to EtOH exposure to identify mechanistic linkages. Methods Hippocampi and cerebella were microdissected at postnatal day (P)10, from control C57BL/6J mouse pups, and pups treated with 4 g/kg of EtOH from P4 to P9. RNA was isolated and RNA‐seq analysis was performed. We compared gene expression in EtOH‐ and vehicle‐treated control neonates and performed biological pathway‐overrepresentation analysis. Results While EtOH exposure resulted in the general induction of genes associated with the S‐phase of mitosis in both cerebellum and hippocampus, overall there was little overlap in differentially regulated genes and associated biological pathways between these regions. In cerebellum, EtOH additionally induced gene expression associated with the G2/M‐phases of the cell cycle and sonic hedgehog signaling, while in hippocampus, EtOH‐induced the pathways for ribosome biogenesis and protein translation. Moreover, EtOH inhibited the transcriptomic identities associated with inhibitory interneuron subpopulations in the hippocampus, while in the cerebellum there was a more pronounced inhibition of transcripts across multiple oligodendrocyte maturation stages. Conclusions These data indicate that during the delayed neurogenic period, EtOH may stimulate the cell cycle, but it otherwise results in widely divergent molecular effects in the hippocampus and cerebellum. Moreover, these data provide evidence for region‐ and cell‐type‐specific vulnerability, which may contribute to the pathogenic effects of developmental EtOH exposure.
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Affiliation(s)
- Marisa R Pinson
- Department of Neuroscience and Experimental Therapeutics, Texas A&M University Health Science Center, Bryan, TX, USA
| | - Kalee N Holloway
- Department of Neurobiology and Developmental Sciences, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - James C Douglas
- Department of Neurobiology and Developmental Sciences, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - Cynthia J M Kane
- Department of Neurobiology and Developmental Sciences, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - Rajesh C Miranda
- Department of Neuroscience and Experimental Therapeutics, Texas A&M University Health Science Center, Bryan, TX, USA
| | - Paul D Drew
- Department of Neurobiology and Developmental Sciences, University of Arkansas for Medical Sciences, Little Rock, AR, USA.,Department of Neurology, University of Arkansas for Medical Sciences, Little Rock, AR, USA
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8
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Gibula-Tarlowska E, Korz V, Lopatynska-Mazurek M, Chlopas-Konowalek A, Grochecki P, Kalaba P, Dragacevic V, Kotlinski R, Kujawski R, Szulc M, Czora-Poczwardowska K, Mikolajczak PL, Lubec G, Kotlinska JH. CE-123, a novel dopamine transporter inhibitor, attenuates locomotor hyperactivity and improves cognitive functions in rat model of fetal alcohol spectrum disorders. Behav Brain Res 2021; 410:113326. [PMID: 33940050 DOI: 10.1016/j.bbr.2021.113326] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 04/23/2021] [Accepted: 04/23/2021] [Indexed: 12/20/2022]
Abstract
Perinatal alcohol exposure can lead to fetal alcohol spectrum disorders (FASD), usually first diagnosed in childhood, that are characterized by hyperactivity, impulsivity and learning and memory disability, among others. To test the hypothesis that dopamine signaling is one of the main factors underlying these impairments, a new atypical dopamine transporter (DAT) inhibitor, CE-123 (1, 3 or 10 mg/kg) was assessed for its potential to overcome the ethanol-induced behavioral effects in a rat model of FASD. In the present study, neonatal rats were exposed to alcohol intubations across the neonatal period (postnatal day (PND)4-9, the third trimester equivalent of human gestation) and, after weaning, the animals (male rats) were assigned randomly to three groups. The first group was tested at PND21 (hyperactivity test). A second group was tested at PND45 (anxiety test), at PND47 (locomotor activity test), at PND49 (spatial cognitive test in the Barnes maze) and PND50 (reversal learning in the Barnes maze). The third group was tested at PND50 (dopamine receptor mRNA expression). Our results support the hypothesis that dopamine signaling is associated with FASD because the dopamine (D1, D2 and D5) receptor mRNA expression was altered in the striatum, hippocampus and prefrontal cortex in adult rats exposed to ethanol during neonatal period. CE-123 (3 and 10 mg/kg) inhibited the hyperactivity and ameliorated (10 mg/kg) the impairment of reversal learning in alcohol-exposed rats. Thus, these findings provide support that CE-123 may be a useful intervention for same of the deficits associated with neonatal ethanol exposure.
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Affiliation(s)
- Ewa Gibula-Tarlowska
- Department of Pharmacology and Pharmacodynamics, Medical University, Lublin, Poland
| | - Volker Korz
- Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | | | | | - Pawel Grochecki
- Department of Pharmacology and Pharmacodynamics, Medical University, Lublin, Poland
| | - Predrag Kalaba
- Department of Pharmaceutical Chemistry, Faculty of Life Sciences, University of Vienna, Vienna, Austria; Paracelsus Private Medical University, Salzburg, Austria
| | - Vladimir Dragacevic
- Department of Pharmaceutical Chemistry, Faculty of Life Sciences, University of Vienna, Vienna, Austria
| | - Robert Kotlinski
- Clinical Department of Cardiac Surgery, University of Rzeszow, Rzeszow, Poland
| | - Radosław Kujawski
- Department of Pharmacology, University of Medical Sciences, Poznan, Poland
| | - Michał Szulc
- Department of Pharmacology, University of Medical Sciences, Poznan, Poland
| | | | | | - Gert Lubec
- Paracelsus Private Medical University, Salzburg, Austria
| | - Jolanta H Kotlinska
- Department of Pharmacology and Pharmacodynamics, Medical University, Lublin, Poland.
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Saito M, Smiley JF, Hui M, Masiello K, Betz J, Ilina M, Saito M, Wilson DA. Neonatal Ethanol Disturbs the Normal Maturation of Parvalbumin Interneurons Surrounded by Subsets of Perineuronal Nets in the Cerebral Cortex: Partial Reversal by Lithium. Cereb Cortex 2020; 29:1383-1397. [PMID: 29462278 DOI: 10.1093/cercor/bhy034] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Revised: 01/02/2018] [Accepted: 01/25/2018] [Indexed: 02/07/2023] Open
Abstract
Reduction in parvalbumin-positive (PV+) interneurons is observed in adult mice exposed to ethanol at postnatal day 7 (P7), a late gestation fetal alcohol spectrum disorder model. To evaluate whether PV+ cells are lost, or PV expression is reduced, we quantified PV+ and associated perineuronal net (PNN)+ cell densities in barrel cortex. While PNN+ cell density was not reduced by P7 ethanol, PV cell density decreased by 25% at P90 with no decrease at P14. PNN+ cells in controls were virtually all PV+, whereas more than 20% lacked PV in ethanol-treated adult animals. P7 ethanol caused immediate apoptosis in 10% of GFP+ cells in G42 mice, which express GFP in a subset of PV+ cells, and GFP+ cell density decreased by 60% at P90 without reduction at P14. The ethanol effect on PV+ cell density was attenuated by lithium treatment at P7 or at P14-28. Thus, reduced PV+ cell density may be caused by disrupted cell maturation, in addition to acute apoptosis. This effect may be regionally specific: in the dentate gyrus, P7 ethanol reduced PV+ cell density by 70% at P14 and both PV+ and PNN+ cell densities by 50% at P90, and delayed lithium did not alleviate ethanol's effect.
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Affiliation(s)
- Mariko Saito
- Division of Neurochemistry, Nathan Kline Institute for Psychiatric Research, Orangeburg, NY, USA.,Department of Psychiatry, NYU School of Medicine, New York, NY, USA
| | - John F Smiley
- Division of Neurochemistry, Nathan Kline Institute for Psychiatric Research, Orangeburg, NY, USA.,Department of Psychiatry, NYU School of Medicine, New York, NY, USA
| | - Maria Hui
- Division of Neurochemistry, Nathan Kline Institute for Psychiatric Research, Orangeburg, NY, USA
| | - Kurt Masiello
- Division of Neurochemistry, Nathan Kline Institute for Psychiatric Research, Orangeburg, NY, USA
| | - Judith Betz
- Division of Neurochemistry, Nathan Kline Institute for Psychiatric Research, Orangeburg, NY, USA
| | - Maria Ilina
- Emotional Brain Institute, Nathan Kline Institute for Psychiatric Research, Orangeburg, NY, USA
| | - Mitsuo Saito
- Department of Psychiatry, NYU School of Medicine, New York, NY, USA.,Emotional Brain Institute, Nathan Kline Institute for Psychiatric Research, Orangeburg, NY, USA
| | - Donald A Wilson
- Division of Analytical Psychopharmacology, Nathan Kline Institute for Psychiatric Research, Orangeburg, NY, USA.,Department of Child and Adolescent Psychiatry, NYU School of Medicine, New York, NY, USA
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10
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Reid HMO, Lysenko-Martin MR, Snowden TM, Thomas JD, Christie BR. A Systematic Review of the Effects of Perinatal Alcohol Exposure and Perinatal Marijuana Exposure on Adult Neurogenesis in the Dentate Gyrus. Alcohol Clin Exp Res 2020; 44:1164-1174. [PMID: 32246781 DOI: 10.1111/acer.14332] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Accepted: 03/24/2020] [Indexed: 12/11/2022]
Abstract
BACKGROUND Marijuana and alcohol are both substances that, when used during pregnancy, may have profound effects on the developing fetus. There is evidence to suggest that both drugs have the capacity to affect working memory, one function of the hippocampal formation; however, there is a paucity of data on how perinatal exposure to alcohol or cannabis impacts the process of adult neurogenesis. METHODS This systematic review examines immunohistochemical data from adult rat and mouse models that assess perinatal alcohol or perinatal marijuana exposure. A comprehensive list of search terms was designed and used to search 3 separate databases. All results were imported to Mendeley and screened by 2 authors. Consensus was reached on a set of final papers that met the inclusion criteria, and their results were summarized. RESULTS Twelve papers were identified as relevant, 10 of which pertained to the effects of perinatal alcohol on the adult hippocampus, and 2 pertained to the effects of perinatal marijuana on the adult hippocampus. Cellular proliferation in the dentate gyrus was not affected in adult rats and mice exposed to alcohol perinatally. In general, perinatal alcohol exposure did not have a significant and reliable effect on the maturation and survival of adult born granule neurons in the dentate gyrus. In contrast, interneuron numbers appear to be reduced in the dentate gyrus of adult rats and mice exposed perinatally to alcohol. Perinatal marijuana exposure was also found to reduce inhibitory interneuron numbers in the dentate gyrus. CONCLUSIONS Perinatal alcohol exposure and perinatal marijuana exposure both act on inhibitory interneurons in the hippocampal formation of adult rats. These findings suggest simultaneous perinatal alcohol and marijuana exposure (SAM) may have a dramatic impact on inhibitory processes in the dentate gyrus.
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Affiliation(s)
- Hannah M O Reid
- From the, Division of Medical Sciences, (HMOR, MRL, TMS, BRC), University of Victoria, Victoria, British Columbia, Canada
| | - Melanie R Lysenko-Martin
- From the, Division of Medical Sciences, (HMOR, MRL, TMS, BRC), University of Victoria, Victoria, British Columbia, Canada
| | - Taylor M Snowden
- From the, Division of Medical Sciences, (HMOR, MRL, TMS, BRC), University of Victoria, Victoria, British Columbia, Canada
| | - Jennifer D Thomas
- Center for Behavioral Teratology, (JDT), San Diego State University, San Diego, California
| | - Brian R Christie
- From the, Division of Medical Sciences, (HMOR, MRL, TMS, BRC), University of Victoria, Victoria, British Columbia, Canada.,Island Medical Program and Department of Cellular and Physiological Sciences, (BRC), University of British Columbia, Victoria, British Columbia
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11
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Xu W, Li H, He C, Frank J, Chen G. Early Ethanol Exposure Inhibits the Differentiation of Hippocampal Dentate Gyrus Granule Cells in a Mouse Model of Fetal Alcohol Spectrum Disorders. Alcohol Clin Exp Res 2020; 44:1112-1122. [PMID: 32220014 DOI: 10.1111/acer.14330] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Accepted: 03/13/2020] [Indexed: 01/22/2023]
Abstract
BACKGROUND Alcohol consumption during pregnancy may damage the developing central nervous system of the fetus and lead to brain structural and functional deficits in the children, known as fetal alcohol spectrum disorders. The underlying mechanisms have not been fully elucidated. Previously, using a third trimester-equivalent mouse model, ethanol (EtOH)-induced behavioral deficits (including spatial learning and memory dysfunction) in the mice were detected on postnatal day (PD) 35. The hippocampal formation is critically involved in spatial learning/memory and contains 2 major neuron populations: the pyramidal cells in the hippocampus proper and the dentate gyrus granule cells (DGGCs) in the dentate gyrus (DG). In rodents, while the pyramidal cells are almost exclusively generated prenatally, the DG granule neurons are majorly generated during the first 2 weeks postnatally, which coincides with the period of EtOH exposure in our mouse model. Therefore, in the current study the effects of EtOH exposure on the development of the DGGCs were examined. METHODS C57BL/6 mice were treated with 4 g/kg of EtOH by intubation on PD 4 to 10 to mimic alcohol exposure to the fetus during the third trimester in humans, and the development of DGGCs was examined by immunohistochemistry and quantified on PD 35. RESULTS EtOH exposure does not affect the number of total or newly generated DGGCs, but reduces the number of mature DGGCs on PD 35 in both male and female mice. The ratio of immature DGGCs over total DGGCs was increased, and the ratio of mature DGGCs over total DGGCs was decreased by EtOH exposure. In addition, no sex-dependent effects of EtOH treatment were detected. CONCLUSION Our data indicate that EtOH exposure in mice during PD 4 to 10 does not affect the generation/proliferation but inhibits the differentiation of the DGGCs on PD 35.
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Affiliation(s)
- Wenhua Xu
- Department of Pharmacology & Nutritional Sciences, University of Kentucky College of Medicine, Lexington, Kentucky.,Department of Neurology, The First Affiliated Hospital of University of Science and Technology of China, Hefei, China
| | - Hui Li
- Department of Pharmacology & Nutritional Sciences, University of Kentucky College of Medicine, Lexington, Kentucky
| | - Caigu He
- Department of Pharmacology & Nutritional Sciences, University of Kentucky College of Medicine, Lexington, Kentucky.,Department of Histology and Embryology, Fujian University of Traditional Chinese Medicine, Fuzhou, China
| | - Jacqueline Frank
- Department of Pharmacology & Nutritional Sciences, University of Kentucky College of Medicine, Lexington, Kentucky
| | - Gang Chen
- Department of Pharmacology & Nutritional Sciences, University of Kentucky College of Medicine, Lexington, Kentucky
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12
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Shivakumar M, Subbanna S, Joshi V, Basavarajappa BS. Postnatal Ethanol Exposure Activates HDAC-Mediated Histone Deacetylation, Impairs Synaptic Plasticity Gene Expression and Behavior in Mice. Int J Neuropsychopharmacol 2020; 23:324-338. [PMID: 32170298 PMCID: PMC7251635 DOI: 10.1093/ijnp/pyaa017] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Revised: 03/06/2020] [Accepted: 03/12/2020] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Alcohol consumption during pregnancy is widespread and contributes to pediatric neurological defects, including hippocampal and neocortex dysfunction, causing cognitive deficits termed fetal alcohol spectrum disorders. However, the critical mechanisms underlying these brain abnormalities remain poorly described. METHODS Using a postnatal ethanol exposure (PEE) animal model and pharmacological, epigenetic, synaptic plasticity-related and behavioral approaches, we discovered a novel persistent epigenetic mechanism of neurodegeneration in neonatal hippocampus and neocortex brain regions and of cognitive decline in adult animals. RESULTS PEE, which activates caspase-3 (CC3, a neurodegeneration marker), enhanced histone deacetylase (HDAC1-HDAC3) levels and reduced histone 3 (H3) and 4 (H4) acetylation (ac) in mature neurons. PEE repressed the expression of several synaptic plasticity genes, such as brain-derived neurotrophic factor, C-Fos, early growth response 1 (Egr1), and activity-regulated cytoskeleton-associated protein (Arc). Detailed studies on Egr1 and Arc expression revealed HDAC enrichment at their promoter regions. HDAC inhibition with trichostatin A (TSA) before PEE rescued H3ac/H4ac levels and prevented CC3 formation. Antagonism/null mutation of cannabinoid receptor type-1 (CB1R) before PEE to inhibit CC3 production prevented Egr1 and Arc loss via epigenetic events. TSA administration before PEE prevented postnatal ethanol-induced loss of Egr1 and Arc expression and neurobehavioral defects in adult mice via epigenetic remodeling. In adult mice, 3-day TSA administration attenuated PEE-induced behavioral defects. CONCLUSIONS These findings demonstrate that CB1R/HDAC-mediated epigenetic remodeling disrupts gene expression and is a critical step in fetal alcohol spectrum disorder-associated cognitive decline but is reversed by restoration of histone acetylation in the brain.
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Affiliation(s)
- Madhu Shivakumar
- Division of Analytical Psychopharmacology, Nathan Kline Institute for Psychiatric Research, Orangeburg, New York
| | - Shivakumar Subbanna
- Division of Analytical Psychopharmacology, Nathan Kline Institute for Psychiatric Research, Orangeburg, New York
| | - Vikram Joshi
- Division of Analytical Psychopharmacology, Nathan Kline Institute for Psychiatric Research, Orangeburg, New York
| | - Balapal S Basavarajappa
- Division of Analytical Psychopharmacology, Nathan Kline Institute for Psychiatric Research, Orangeburg, New York,New York State Psychiatric Institute, New York, New York,Department of Psychiatry, College of Physicians and Surgeons, Columbia University, New York, New York,Department of Psychiatry, New York University Langone Medical Center, New York, New York,Correspondence: Balapal S. Basavarajappa, PhD, Division of Analytical Psychopharmacology, Nathan Kline Institute for Psychiatric Research, 140 Old Orangeburg Rd, Orangeburg, NY 10962 ()
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13
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Harvey RE, Berkowitz LE, Hamilton DA, Clark BJ. The effects of developmental alcohol exposure on the neurobiology of spatial processing. Neurosci Biobehav Rev 2019; 107:775-794. [PMID: 31526818 PMCID: PMC6876993 DOI: 10.1016/j.neubiorev.2019.09.018] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Revised: 08/02/2019] [Accepted: 09/11/2019] [Indexed: 01/20/2023]
Abstract
The consumption of alcohol during gestation is detrimental to the developing central nervous system. One functional outcome of this exposure is impaired spatial processing, defined as sensing and integrating information pertaining to spatial navigation and spatial memory. The hippocampus, entorhinal cortex, and anterior thalamus are brain regions implicated in spatial processing and are highly susceptible to the effects of developmental alcohol exposure. Some of the observed effects of alcohol on spatial processing may be attributed to changes at the synaptic to circuit level. In this review, we first describe the impact of developmental alcohol exposure on spatial behavior followed by a summary of the development of brain areas involved in spatial processing. We then provide an examination of the consequences of prenatal and early postnatal alcohol exposure in rodents on hippocampal, anterior thalamus, and entorhinal cortex-dependent spatial processing from the cellular to behavioral level. We conclude by highlighting several unanswered questions which may provide a framework for future investigation.
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Affiliation(s)
- Ryan E Harvey
- Department of Psychology, University of New Mexico, Albuquerque, NM, United States
| | - Laura E Berkowitz
- Department of Psychology, University of New Mexico, Albuquerque, NM, United States
| | - Derek A Hamilton
- Department of Psychology, University of New Mexico, Albuquerque, NM, United States
| | - Benjamin J Clark
- Department of Psychology, University of New Mexico, Albuquerque, NM, United States.
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14
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Buckley DM, Sidik A, Kar RD, Eberhart JK. Differentially sensitive neuronal subpopulations in the central nervous system and the formation of hindbrain heterotopias in ethanol-exposed zebrafish. Birth Defects Res 2019; 111:700-713. [PMID: 30793540 DOI: 10.1002/bdr2.1477] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Revised: 01/22/2019] [Accepted: 01/24/2019] [Indexed: 12/21/2022]
Abstract
BACKGROUND A cardinal feature of prenatal ethanol exposure is CNS damage, resulting in a continuum of neurological and behavioral impairments that are described by the term fetal alcohol spectrum disorders (FASD). FASDs are variable and depend on several factors, including the amount, timing, and duration of prenatal ethanol exposure. To enhance interventions for CNS dysfunction, it is necessary to identify ethanol-sensitive neuronal populations and expand the understanding of factors that modify ethanol teratogenesis. METHODS To investigate the susceptibility of different neuronal subtypes, we exposed transgenic zebrafish (Danio rerio) to several ethanol concentrations (0.25, 0.5, 1.0, 1.5, or 2.0%), at different hours post fertilization (hpf; 0, 6, or 24 hpf), for various durations (0-24, 0-48, 4-24, 6-24, 6-48,or 24-48 hpf). Following exposure, embryo survival rates were determined, and CNS neurogenesis, differentiation, and patterning were assessed. RESULTS Embryo survival rates decrease as ethanol concentrations increase and drastically decline when exposed from 0-24 hpf compared to 4-24 hpf. Abnormal tangential migration of facial motor neurons is observed in isl1:gfp embryos exposed to ethanol concentrations as low as 0.25%, and the formation of IVth ventricle heterotopias are revealed by embryos exposed to ≥1.0% ethanol. Whereas, expression of olig2:dsred and ptf1a:gfp in the cerebellum and spinal cord are largely unaffected. While levels of etv4 mRNA are overtly resistant to ethanol, we observe significant reductions in ptch2 mRNA levels. CONCLUSIONS These data show differentially sensitive CNS neuron subpopulations with susceptibility to low levels of ethanol. In addition, these data reveal the formation of ethanol-induced hindbrain heterotopias.
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Affiliation(s)
- Desire M Buckley
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, Texas
| | - Alfire Sidik
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, Texas
| | - Ranjeet D Kar
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, Texas
| | - Johann K Eberhart
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, Texas
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15
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Subbanna S, Joshi V, Basavarajappa BS. Activity-dependent Signaling and Epigenetic Abnormalities in Mice Exposed to Postnatal Ethanol. Neuroscience 2018; 392:230-240. [PMID: 30031835 DOI: 10.1016/j.neuroscience.2018.07.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Revised: 07/03/2018] [Accepted: 07/05/2018] [Indexed: 12/21/2022]
Abstract
Postnatal ethanol exposure has been shown to cause persistent defects in hippocampal synaptic plasticity and disrupt learning and memory processes. However, the mechanisms responsible for these abnormalities are less well studied. We evaluated the influence of postnatal ethanol exposure on several signaling and epigenetic changes and on expression of the activity-regulated cytoskeletal (Arc) protein in the hippocampus of adult offspring under baseline conditions and after a Y-maze spatial memory (SP) behavior (activity). Postnatal ethanol treatment impaired pCaMKIV and pCREB in naïve mice without affecting H4K8ac, H3K14ac and H3K9me2 levels. The Y-maze increased pCaMKIV, pCREB, H4K8ac and H3K14ac levels in saline-treated mice but not in ethanol-treated mice; while H3K9me2 levels were enhanced in ethanol-exposed animals compared to saline groups. Like previous observations, ethanol not only reduced Arc expression in naïve mice but also behaviorally induced Arc expression. ChIP results suggested that reduced H3K14ac and H4K8ac in the Arc gene promoter is because of impaired CBP, and increased H3K9me2 is due to the enhanced recruitment of G9a. The CB1R antagonist and a G9a/GLP inhibitor, which were shown to rescue postnatal ethanol-triggered synaptic plasticity and learning and memory deficits, were able to prevent the negative effects of ethanol on activity-dependent signaling, epigenetics and Arc expression. Together, these findings provide a molecular mechanism involving signaling and epigenetic cascades that collectively are responsible for the neurobehavioral deficits associated with an animal model of fetal alcohol spectrum disorders (FASD).
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Affiliation(s)
- Shivakumar Subbanna
- Division of Analytical Psychopharmacology, Nathan Kline Institute for Psychiatric Research, Orangeburg, NY 10962, USA
| | - Vikram Joshi
- Division of Analytical Psychopharmacology, Nathan Kline Institute for Psychiatric Research, Orangeburg, NY 10962, USA
| | - Balapal S Basavarajappa
- Division of Analytical Psychopharmacology, Nathan Kline Institute for Psychiatric Research, Orangeburg, NY 10962, USA; Department of Psychiatry, College of Physicians & Surgeons, Columbia University, New York, NY, 10032, USA; Department of Psychiatry, New York University Langone Medical Center, New York, NY, USA.
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16
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Pinazo-Duran MD, Renau-Piqueras J, Guerri C, Strömland K. Optic Nerve Hypoplasia in Fetal Alcohol Syndrome: An Update. Eur J Ophthalmol 2018; 7:262-70. [PMID: 9352281 DOI: 10.1177/112067219700700311] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Optic nerve hypoplasia was detected in up to one half of a group of Swedish children born to alcoholic mothers. Using an experimental model of pre- and postnatal alcohol exposure in rats fed a liquid diet, reduced optic nerve size from gestational day 21 (294 ± 26×102 μm2 vs 502 ± 16×102 μm2; n=6; p≤0.001) to later in development was observed as a result of the daily mean blood alcohol levels achieved in dams and their offspring. Altered glial cells and degenerating and atrophic optic axons, myelin sheaths and ganglion cells were frequent in the alcohol-exposed optic nerves. Smaller optic nerve (1,918 ± 61×102 μm2 vs 2.195 ± 40×102 μm2; n=4; p≤0.001), reduced gaglion cell and axonal densities, and ultrastructural damage to the macroglial cells and myelin sheaths were also detected in the treated group. All these changes remained in the retina and optic nerve of the oldest rats, as a consequence of the long-lasting effects of prenatal alcohol exposure. In summary, alcohol as a major teratogenic agent may induce dysmorphogenesis and irremediable damage to the retina and optic nerve, which frequently manifests itself as hypoplastic optic nerve.
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Affiliation(s)
- M D Pinazo-Duran
- Institute of Cytological Research and Investigation Center, University Hospital La Fe, Valencia, Spain
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17
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Subbanna S, Nagre NN, Shivakumar M, Joshi V, Psychoyos D, Kutlar A, Umapathy NS, Basavarajappa BS. CB1R-Mediated Activation of Caspase-3 Causes Epigenetic and Neurobehavioral Abnormalities in Postnatal Ethanol-Exposed Mice. Front Mol Neurosci 2018; 11:45. [PMID: 29515368 PMCID: PMC5826222 DOI: 10.3389/fnmol.2018.00045] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Accepted: 02/02/2018] [Indexed: 12/15/2022] Open
Abstract
Alcohol exposure can affect brain development, leading to long-lasting behavioral problems, including cognitive impairment, which together is defined as fetal alcohol spectrum disorder (FASD). However, the fundamental mechanisms through which this occurs are largely unknown. In this study, we report that the exposure of postnatal day 7 (P7) mice to ethanol activates caspase-3 via cannabinoid receptor type-1 (CB1R) in neonatal mice and causes a reduction in methylated DNA binding protein (MeCP2) levels. The developmental expression of MeCP2 in mice is closely correlated with synaptogenesis and neuronal maturation. It was shown that ethanol treatment of P7 mice enhanced Mecp2 mRNA levels but reduced protein levels. The genetic deletion of CB1R prevented, and administration of a CB1R antagonist before ethanol treatment of P7 mice inhibited caspase-3 activation. Additionally, it reversed the loss of MeCP2 protein, cAMP response element binding protein (CREB) activation, and activity-regulated cytoskeleton-associated protein (Arc) expression. The inhibition of caspase-3 activity prior to ethanol administration prevented ethanol-induced loss of MeCP2, CREB activation, epigenetic regulation of Arc expression, long-term potentiation (LTP), spatial memory deficits and activity-dependent impairment of several signaling molecules, including MeCP2, in adult mice. Collectively, these results reveal that the ethanol-induced CB1R-mediated activation of caspase-3 degrades the MeCP2 protein in the P7 mouse brain and causes long-lasting neurobehavioral deficits in adult mice. This CB1R-mediated instability of MeCP2 during active synaptic maturation may disrupt synaptic circuit maturation and lead to neurobehavioral abnormalities, as observed in this animal model of FASD.
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Affiliation(s)
- Shivakumar Subbanna
- Division of Analytical Psychopharmacology, Nathan Kline Institute for Psychiatric Research, New York, NY, United States
| | - Nagaraja N. Nagre
- Division of Analytical Psychopharmacology, Nathan Kline Institute for Psychiatric Research, New York, NY, United States
| | - Madhu Shivakumar
- Division of Analytical Psychopharmacology, Nathan Kline Institute for Psychiatric Research, New York, NY, United States
| | - Vikram Joshi
- Division of Analytical Psychopharmacology, Nathan Kline Institute for Psychiatric Research, New York, NY, United States
| | - Delphine Psychoyos
- Institute of Biosciences and Technology, Texas A&M University Health Science Center, Houston, TX, United States
| | - Abdullah Kutlar
- Center for Blood Disorders, Augusta University, Augusta, GA, United States
| | | | - Balapal S. Basavarajappa
- Division of Analytical Psychopharmacology, Nathan Kline Institute for Psychiatric Research, New York, NY, United States
- New York State Psychiatric Institute, New York, NY, United States
- Department of Psychiatry, College of Physicians & Surgeons, Columbia University, New York, NY, United States
- Department of Psychiatry, New York University Langone Medical Center, New York, NY, United States
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18
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Goeke CM, Roberts ML, Hashimoto JG, Finn DA, Guizzetti M. Neonatal Ethanol and Choline Treatments Alter the Morphology of Developing Rat Hippocampal Pyramidal Neurons in Opposite Directions. Neuroscience 2018; 374:13-24. [PMID: 29391132 DOI: 10.1016/j.neuroscience.2018.01.031] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Revised: 01/08/2018] [Accepted: 01/12/2018] [Indexed: 10/18/2022]
Abstract
Some of the neurobehavioral deficits identified in children with Fetal Alcohol Spectrum Disorders (FASDs) have been recapitulated in a binge model of gestational third trimester-equivalent ethanol (EtOH) exposure, in which Sprague-Dawley rats are intragastrically intubated between post-natal day (PD) 4 and PD9 with high doses of EtOH. In this model, the ameliorating effects of choline (Chol) administration on hippocampus-dependent behaviors altered by EtOH have also been extensively documented. In the present study, we investigated the effects of EtOH (5 g/kg/day) and/or Chol (100 mg/kg/day) on morphometric parameters of CA1 pyramidal neurons by Golgi-Cox staining followed by Neurolucida tracing and analysis. We found that EtOH increased apical dendrite complexity in male and female pups neonatally exposed to EtOH. EtOH did not significantly affect basal dendrite parameters in female and male rats. Interestingly, Chol treatments decreased basal dendrites' length, number, and maximal terminal distance in male pups. When pups were co-treated with EtOH and Chol, Chol did not rescue the effect of EtOH. In conclusion, EtOH increases while Chol decreases dendritic length and arborization of hippocampal CA1 neurons in PD9 rats. We hypothesize that developmental EtOH exposure induces a premature maturation of neurons, leading to early restriction of neuronal plasticity while Chol treatments delay the normal program of neuronal maturation and therefore prolong the window of maximal plasticity. Chol does not prevent the effects of developmental alcohol exposure on hippocampal pyramidal neurons' morphology characterized in the present study, although whether prolonged Chol administration after developmental EtOH exposure rectifies EtOH damage remains to be assessed.
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Affiliation(s)
- C M Goeke
- VA Portland Health Care System, Portland, OR 97239, USA; Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, OR 97239, USA
| | - M L Roberts
- VA Portland Health Care System, Portland, OR 97239, USA
| | - J G Hashimoto
- VA Portland Health Care System, Portland, OR 97239, USA; Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, OR 97239, USA
| | - D A Finn
- VA Portland Health Care System, Portland, OR 97239, USA; Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, OR 97239, USA
| | - M Guizzetti
- VA Portland Health Care System, Portland, OR 97239, USA; Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, OR 97239, USA.
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Ruggiero MJ, Boschen KE, Roth TL, Klintsova AY. Sex Differences in Early Postnatal Microglial Colonization of the Developing Rat Hippocampus Following a Single-Day Alcohol Exposure. J Neuroimmune Pharmacol 2017; 13:189-203. [PMID: 29274031 DOI: 10.1007/s11481-017-9774-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Accepted: 12/03/2017] [Indexed: 02/08/2023]
Abstract
Microglia are involved in various homeostatic processes in the brain, including phagocytosis, apoptosis, and synaptic pruning. Sex differences in microglia colonization of the developing brain have been reported, but have not been established following alcohol insult. Developmental alcohol exposure represents a neuroimmune challenge that may contribute to cognitive dysfunction prevalent in humans with Fetal Alcohol Spectrum Disorders (FASD) and in rodent models of FASD. Most studies have investigated neuroimmune activation following adult alcohol exposure or following multiple exposures. The current study uses a single day binge alcohol exposure model (postnatal day [PD] 4) to examine sex differences in the neuroimmune response in the developing rat hippocampus on PD5 and 8. The neuroimmune response was evaluated through measurement of microglial number and cytokine gene expression at both time points. Male pups had higher microglial number compared to females in many hippocampal subregions on PD5, but this difference disappeared by PD8, unless exposed to alcohol. Expression of pro-inflammatory marker CD11b was higher on PD5 in alcohol-exposed (AE) females compared to AE males. After alcohol exposure, C-C motif chemokine ligand 4 (CCL4) was significantly increased in female AE pups on PD5 and PD8. Tumor necrosis factor-α (TNF-α) levels were also upregulated by AE in males on PD8. The results demonstrate a clear difference between the male and female neuroimmune response to an AE challenge, which also occurs in a time-dependent manner. These findings are significant as they add to our knowledge of specific sex-dependent effects of alcohol exposure on microglia within the developing brain.
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Affiliation(s)
- M J Ruggiero
- Department of Psychological and Brain Sciences, University of Delaware, 108 Wolf Hall, Newark, DE, 19716, USA
| | - K E Boschen
- Department of Psychological and Brain Sciences, University of Delaware, 108 Wolf Hall, Newark, DE, 19716, USA
| | - T L Roth
- Department of Psychological and Brain Sciences, University of Delaware, 108 Wolf Hall, Newark, DE, 19716, USA
| | - A Y Klintsova
- Department of Psychological and Brain Sciences, University of Delaware, 108 Wolf Hall, Newark, DE, 19716, USA.
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20
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Gavin DP, Grayson DR, Varghese SP, Guizzetti M. Chromatin Switches during Neural Cell Differentiation and Their Dysregulation by Prenatal Alcohol Exposure. Genes (Basel) 2017; 8:E137. [PMID: 28492482 PMCID: PMC5448011 DOI: 10.3390/genes8050137] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Revised: 05/01/2017] [Accepted: 05/06/2017] [Indexed: 02/07/2023] Open
Abstract
Prenatal alcohol exposure causes persistent neuropsychiatric deficits included under the term fetal alcohol spectrum disorders (FASD). Cellular identity emerges from a cascade of intrinsic and extrinsic (involving cell-cell interactions and signaling) processes that are partially initiated and maintained through changes in chromatin structure. Prenatal alcohol exposure influences neuronal and astrocyte development, permanently altering brain connectivity. Prenatal alcohol exposure also alters chromatin structure through histone and DNA modifications. However, the data linking alcohol-induced differentiation changes with developmental alterations in chromatin structure remain to be elucidated. In the first part of this review, we discuss the sequence of chromatin structural changes involved in neural cell differentiation during normal development. We then discuss the effects of prenatal alcohol on developmental histone modifications and DNA methylation in the context of neurogenesis and astrogliogenesis. We attempt to synthesize the developmental literature with the FASD literature, proposing that alcohol-induced changes to chromatin structure account for altered neurogenesis and astrogliogenesis as well as altered neuron and astrocyte differentiation. Together these changes may contribute to the cognitive and behavioral abnormalities in FASD. Future studies using standardized alcohol exposure paradigms at specific developmental stages will advance the understanding of how chromatin structural changes impact neural cell fate and maturation in FASD.
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Affiliation(s)
- David P Gavin
- Jesse Brown Veterans Affairs Medical Center, 820 South Damen Avenue (M/C 151), Chicago, IL 60612, USA.
- Center for Alcohol Research in Epigenetics, Department of Psychiatry, University of Illinois at Chicago, 1601 W. Taylor St., Chicago, IL 60612, USA.
| | - Dennis R Grayson
- Center for Alcohol Research in Epigenetics, Department of Psychiatry, University of Illinois at Chicago, 1601 W. Taylor St., Chicago, IL 60612, USA.
| | - Sajoy P Varghese
- Jesse Brown Veterans Affairs Medical Center, 820 South Damen Avenue (M/C 151), Chicago, IL 60612, USA.
| | - Marina Guizzetti
- Department of Behavioral Neuroscience, Oregon Health & Science University, 3181 SW Sam Jackson Park Road L470, Portland, OR 97239, USA.
- Veterans Affairs Portland Health Care System, 3710 Southwest US Veterans Hospital Road, Portland, OR 97239, USA.
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du Plooy CP, Malcolm-Smith S, Adnams CM, Stein DJ, Donald KA. The Effects of Prenatal Alcohol Exposure on Episodic Memory Functioning: A Systematic Review: Table 1. Arch Clin Neuropsychol 2016; 31:710-726. [DOI: 10.1093/arclin/acw067] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/01/2016] [Indexed: 01/04/2023] Open
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22
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Saito M, Chakraborty G, Hui M, Masiello K, Saito M. Ethanol-Induced Neurodegeneration and Glial Activation in the Developing Brain. Brain Sci 2016; 6:brainsci6030031. [PMID: 27537918 PMCID: PMC5039460 DOI: 10.3390/brainsci6030031] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Revised: 08/05/2016] [Accepted: 08/12/2016] [Indexed: 11/16/2022] Open
Abstract
Ethanol induces neurodegeneration in the developing brain, which may partially explain the long-lasting adverse effects of prenatal ethanol exposure in fetal alcohol spectrum disorders (FASD). While animal models of FASD show that ethanol-induced neurodegeneration is associated with glial activation, the relationship between glial activation and neurodegeneration has not been clarified. This review focuses on the roles of activated microglia and astrocytes in neurodegeneration triggered by ethanol in rodents during the early postnatal period (equivalent to the third trimester of human pregnancy). Previous literature indicates that acute binge-like ethanol exposure in postnatal day 7 (P7) mice induces apoptotic neurodegeneration, transient activation of microglia resulting in phagocytosis of degenerating neurons, and a prolonged increase in glial fibrillary acidic protein-positive astrocytes. In our present study, systemic administration of a moderate dose of lipopolysaccharides, which causes glial activation, attenuates ethanol-induced neurodegeneration. These studies suggest that activation of microglia and astrocytes by acute ethanol in the neonatal brain may provide neuroprotection. However, repeated or chronic ethanol can induce significant proinflammatory glial reaction and neurotoxicity. Further studies are necessary to elucidate whether acute or sustained glial activation caused by ethanol exposure in the developing brain can affect long-lasting cellular and behavioral abnormalities observed in the adult brain.
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Affiliation(s)
- Mariko Saito
- Division of Neurochemisty, Nathan S. Kline Institute for Psychiatric Research, 140 Old Orangeburg Rd., Orangeburg, NY 10962, USA.
- Department of Psychiatry, New York University Langone Medical Center, 550 First Avenue, New York, NY 10016, USA.
| | - Goutam Chakraborty
- Division of Neurochemisty, Nathan S. Kline Institute for Psychiatric Research, 140 Old Orangeburg Rd., Orangeburg, NY 10962, USA.
| | - Maria Hui
- Division of Neurochemisty, Nathan S. Kline Institute for Psychiatric Research, 140 Old Orangeburg Rd., Orangeburg, NY 10962, USA.
| | - Kurt Masiello
- Division of Neurochemisty, Nathan S. Kline Institute for Psychiatric Research, 140 Old Orangeburg Rd., Orangeburg, NY 10962, USA.
| | - Mitsuo Saito
- Department of Psychiatry, New York University Langone Medical Center, 550 First Avenue, New York, NY 10016, USA.
- Division of Analytical Psychopharmacology, Nathan S. Kline Institute for Psychiatric Research, 140 Old Orangeburg Rd., Orangeburg, NY 10962, USA.
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Kane CJM, Drew PD. Inflammatory responses to alcohol in the CNS: nuclear receptors as potential therapeutics for alcohol-induced neuropathologies. J Leukoc Biol 2016; 100:951-959. [PMID: 27462100 DOI: 10.1189/jlb.3mr0416-171r] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Accepted: 07/11/2016] [Indexed: 01/14/2023] Open
Abstract
Fetal alcohol spectrum disorder (FASD), which results from ethanol exposure during pregnancy, and alcohol use disorder (AUD), which includes both binge and chronic alcohol abuse, are strikingly common and costly at personal and societal levels. These disorders are associated with significant pathology, including that observed in the CNS. It is now appreciated in both humans and animal models that ethanol can induce inflammation in the CNS. Neuroinflammation is hypothesized to contribute to the neuropathologic and behavioral consequences in FASD and AUD. In this review, we: 1) summarize the evidence of alcohol-induced CNS inflammation, 2) outline cellular and molecular mechanisms that may underlie alcohol induction of CNS inflammation, and 3) discuss the potential of nuclear receptor agonists for prevention or treatment of neuropathologies associated with FASD and AUD.
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Affiliation(s)
- Cynthia J M Kane
- Department of Neurobiology and Developmental Sciences, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
| | - Paul D Drew
- Department of Neurobiology and Developmental Sciences, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
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Heaton MB, Paiva M, Kubovec S. Differential effects of ethanol on bid, tBid, and Bax:tBid interactions in postnatal day 4 and postnatal day 7 rat cerebellum. Alcohol Clin Exp Res 2016; 39:55-63. [PMID: 25623406 DOI: 10.1111/acer.12603] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2014] [Accepted: 10/13/2014] [Indexed: 12/27/2022]
Abstract
BACKGROUND Exposure to ethanol (EtOH) during central nervous system (CNS) development can lead to a wide array of neuroanatomical, behavioral, and cognitive abnormalities, broadly subsumed under the fetal alcohol spectrum disorder classification. One mode of EtOH-induced interference in the normal developmental program appears to be through induction of apoptotic processes mediated by the Bcl-2 family of survival-regulatory proteins. The present series of studies investigated the role of the Bcl-2-related, pro-apoptotic Bid protein, and its truncated, apoptotically active fragment, tBid, in developmental EtOH neurotoxicity. METHODS Protein analyses were made via enzyme-linked immunosorbent assays (ELISA) in neonatal rat cerebellum, of basal Bid, and of Bid and tBid, following EtOH exposure via vapor inhalation, at an age of peak EtOH sensitivity in this region (postnatal day 4 [P4]) and a later age of relative resistance (P7). ELISA analyses were also made of Bax:tBid heterodimers, a process which activates Bax, essential for its apoptotic functioning. Finally, in vitro assessments of the importance of tBid to EtOH neurotoxicity were made in cultured cerebellar granule cells, using a specific tBid inhibitor. RESULTS Basal levels of Bid were higher at P4 compared to P7, possibly contributing to the differential sensitivity. EtOH exposure elicited further increases in cytosolic Bid and mitochondrial tBid when administration was at P4, but not at P7. Bax:tBid heterodimers were markedly increased by EtOH exposure on P4, an increase which persisted even 2 hours after termination of treatment. Similar effects were not seen at P7. The in vitro analyses revealed that tBid inhibition provided complete protection against EtOH-induced cell death and depressed EtOH-mediated cytochrome-c release. CONCLUSIONS These results suggest that Bid/tBid may be important elements in EtOH-mediated neurotoxicity during CNS development. The molecular processes and interactions revealed may represent critical points which can be targeted in studies concerned with designing possible therapeutic strategies for minimizing these devastative effects.
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Affiliation(s)
- Marieta B Heaton
- Department of Neuroscience, University of Florida College of Medicine, Gainesville, Florida; McKnight Brain Institute, Gainesville, Florida; Center for Addiction Research and Education, Gainesville, Florida
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Li H, Chen J, Qi Y, Dai L, Zhang M, Frank JA, Handshoe JW, Cui J, Xu W, Chen G. Deficient PKR in RAX/PKR Association Ameliorates Ethanol-Induced Neurotoxicity in the Developing Cerebellum. THE CEREBELLUM 2016; 14:386-97. [PMID: 25592072 DOI: 10.1007/s12311-015-0644-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Ethanol-induced neuronal loss is closely related to the pathogenesis of fetal alcohol spectrum disorders. The cerebellum is one of the brain areas that are most sensitive to ethanol. The mechanism underlying ethanol neurotoxicity remains unclear. Our previous in vitro studies have shown that the double-stranded RNA (dsRNA)-activated protein kinase (PKR) regulates neuronal apoptosis upon ethanol exposure and ethanol activates PKR through association with its intracellular activator RAX. However, the role of PKR and its interaction with RAX in vivo have not been investigated. In the current study, by utilizing N-PKR-/- mice, C57BL/6J mice with a deficient RAX-binding domain in PKR, we determined the critical role of RAX/PKR association in PKR-regulated ethanol neurotoxicity in the developing cerebellum. Our data indicate that while N-PKR-/- mice have a similar BAC profile as wild-type mice, ethanol induces less brain/body mass reduction as well as cerebellar neuronal loss. In addition, ethanol promotes interleukin-1β (IL-1β) secretion, and IL-1β is a master cytokine regulating inflammatory response. Importantly, ethanol-promoted IL-1β secretion is inhibited in the developing cerebellum of N-PKR-/- mice. Thus, RAX/PKR interaction and PKR activation regulate ethanol neurotoxicity in the developing cerebellum, which may involve ethanol-induced neuroinflammation. Further, PKR could be a possible target for pharmacological intervention to prevent or treat fetal alcohol spectrum disorder (FASD).
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Affiliation(s)
- Hui Li
- Department Pharmacology & Nutritional Sciences, University of Kentucky College of Medicine, MN306, UKMC, 800 Rose street, Lexington, KY, 40536, USA
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Goodfellow MJ, Abdulla KA, Lindquist DH. Neonatal Ethanol Exposure Impairs Trace Fear Conditioning and Alters NMDA Receptor Subunit Expression in Adult Male and Female Rats. Alcohol Clin Exp Res 2016; 40:309-18. [DOI: 10.1111/acer.12958] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2015] [Accepted: 11/04/2015] [Indexed: 01/10/2023]
Affiliation(s)
| | - Khalid A. Abdulla
- Department of Psychology; The Ohio State University; Columbus Ohio
- Department of Neuroscience; The Ohio State University; Columbus Ohio
| | - Derick H. Lindquist
- Department of Psychology; The Ohio State University; Columbus Ohio
- Department of Neuroscience; The Ohio State University; Columbus Ohio
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Fetal Alcohol Spectrum Disorder: Potential Role of Endocannabinoids Signaling. Brain Sci 2015; 5:456-93. [PMID: 26529026 PMCID: PMC4701023 DOI: 10.3390/brainsci5040456] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Revised: 10/19/2015] [Accepted: 10/19/2015] [Indexed: 12/15/2022] Open
Abstract
One of the unique features of prenatal alcohol exposure in humans is impaired cognitive and behavioral function resulting from damage to the central nervous system (CNS), which leads to a spectrum of impairments referred to as fetal alcohol spectrum disorder (FASD). Human FASD phenotypes can be reproduced in the rodent CNS following prenatal ethanol exposure. Several mechanisms are expected to contribute to the detrimental effects of prenatal alcohol exposure on the developing fetus, particularly in the developing CNS. These mechanisms may act simultaneously or consecutively and differ among a variety of cell types at specific developmental stages in particular brain regions. Studies have identified numerous potential mechanisms through which alcohol can act on the fetus. Among these mechanisms are increased oxidative stress, mitochondrial damage, interference with the activity of growth factors, glia cells, cell adhesion molecules, gene expression during CNS development and impaired function of signaling molecules involved in neuronal communication and circuit formation. These alcohol-induced deficits result in long-lasting abnormalities in neuronal plasticity and learning and memory and can explain many of the neurobehavioral abnormalities found in FASD. In this review, the author discusses the mechanisms that are associated with FASD and provides a current status on the endocannabinoid system in the development of FASD.
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Huebner SM, Tran TD, Rufer ES, Crump PM, Smith SM. Maternal iron deficiency worsens the associative learning deficits and hippocampal and cerebellar losses in a rat model of fetal alcohol spectrum disorders. Alcohol Clin Exp Res 2015; 39:2097-107. [PMID: 26399568 DOI: 10.1111/acer.12876] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2015] [Accepted: 08/09/2015] [Indexed: 01/08/2023]
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 (ps ≤ 0.001) and conditioned response [CR] percentage (ps ≤ 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 (ps < 0.001) and CA1 cellularity (ps < 0.005). CR amplitude correlated with IPN cellularity (delay: r = 0.871, trace: r = 0.703, ps < 0.001) and CA1 cellularity (delay: r = 0.792, trace: r = 0.846, ps < 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.
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Affiliation(s)
- Shane M Huebner
- Departments of Nutritional Sciences, University of Wisconsin-Madison, Madison, Wisconsin
| | - Tuan D Tran
- Department of Psychology, Multidisciplinary Studies Program in Neuroscience, East Carolina University, Greenville, North Carolina
| | - Echoleah S Rufer
- Departments of Nutritional Sciences, University of Wisconsin-Madison, Madison, Wisconsin
| | - Peter M Crump
- Computing and Biometry, University of Wisconsin-Madison, Madison, Wisconsin
| | - Susan M Smith
- Departments of Nutritional Sciences, University of Wisconsin-Madison, Madison, Wisconsin
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Safety assessment for ethanol-based topical antiseptic use by health care workers: Evaluation of developmental toxicity potential. Regul Toxicol Pharmacol 2015. [PMID: 26212636 DOI: 10.1016/j.yrtph.2015.07.015] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Ethanol-based topical antiseptic hand rubs, commonly referred to as alcohol-based hand sanitizers (ABHS), are routinely used as the standard of care to reduce the presence of viable bacteria on the skin and are an important element of infection control procedures in the healthcare industry. There are no reported indications of safety concerns associated with the use of these products in the workplace. However, the prevalence of such alcohol-based products in healthcare facilities and safety questions raised by the U.S. FDA led us to assess the potential for developmental toxicity under relevant product-use scenarios. Estimates from a physiologically based pharmacokinetic modeling approach suggest that occupational use of alcohol-based topical antiseptics in the healthcare industry can generate low, detectable concentrations of ethanol in blood. This unintended systemic dose probably reflects contributions from both dermal absorption and inhalation of volatilized product. The resulting internal dose is low, even under hypothetical, worst case intensive use assumptions. A significant margin of exposure (MOE) exists compared to demonstrated effect levels for developmental toxicity under worst case use scenarios, and the MOE is even more significant for typical anticipated occupational use patterns. The estimated internal doses of ethanol from topical application of alcohol-based hand sanitizers are also in the range of those associated with consumption of non-alcoholic beverages (i.e., non-alcoholic beer, flavored water, and orange juice), which are considered safe for consumers. Additionally, the estimated internal doses associated with expected exposure scenarios are below or in the range of the expected internal doses associated with the current occupational exposure limit for ethanol set by the Occupational Safety and Health Administration. These results support the conclusion that there is no significant risk of developmental or reproductive toxicity from repeated occupational exposures and high frequency use of ABHSs or surgical scrubs. Overall, the data support the conclusion that alcohol-based hand sanitizer products are safe for their intended use in hand hygiene as a critical infection prevention strategy in healthcare settings.
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Perkins AE, Fadel JR, Kelly SJ. The effects of postnatal alcohol exposure and galantamine on the context pre-exposure facilitation effect and acetylcholine efflux using in vivo microdialysis. Alcohol 2015; 49:193-205. [PMID: 25837482 DOI: 10.1016/j.alcohol.2015.01.010] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Revised: 01/05/2015] [Accepted: 01/23/2015] [Indexed: 12/12/2022]
Abstract
Fetal alcohol spectrum disorders (FASD) are characterized by damage to multiple brain regions, including the hippocampus, which is involved in learning and memory. The acetylcholine neurotransmitter system provides major input to the hippocampus and is a possible target of developmental alcohol exposure. Alcohol (3.0 g/kg/day) was administered via intubation to male rat pups (postnatal day [PD] 2-10; ethanol-treated [ET]). Controls received a sham intubation (IC) or no treatment (NC). Acetylcholine efflux was measured using in vivo microdialysis (PD 32-35). ET animals were not different at baseline, but had decreased K(+)/Ca(2+)-induced acetylcholine efflux compared to NC animals and an enhanced acetylcholine response to galantamine (acetylcholinesterase inhibitor; 2.0 mg/kg) compared to both control groups. A separate cohort of animals was tested in the context pre-exposure facilitation effect task (CPFE; PD 30-32) following postnatal alcohol exposure and administration of galantamine (2.0 mg/kg; PD 11-30). Neither chronic galantamine nor postnatal alcohol exposure influenced performance in the CPFE task. Using immunohistochemistry, we found that neither alcohol exposure nor behavioral testing significantly altered the density of vesicular acetylcholine transporter or alpha7 nicotinic acetylcholine receptor in the ventral hippocampus (CA1). In the medial septum, the average number of choline acetyltransferase (ChAT+) cells was increased in ET animals that displayed the context-shock association; there were no changes in IC and NC animals that learned the context-shock association or in any animals that were in the control task that entailed no learning. Taken together, these results indicate that the hippocampal acetylcholine system is significantly disrupted under conditions of pharmacological manipulations (e.g., galantamine) in alcohol-exposed animals. Furthermore, ChAT was up‑regulated in ET animals that learned the CPFE, which may account for their ability to perform this task. In sum, developmental alcohol exposure may disrupt learning and memory in adolescence via a cholinergic mechanism.
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Affiliation(s)
- Amy E Perkins
- Department of Psychology, University of South Carolina, 1512 Pendleton St., Columbia, SC 29208, USA
| | - Jim R Fadel
- Department of Pharmacology, Physiology, and Neuroscience, University of South Carolina School of Medicine, Columbia, SC 29208, USA
| | - Sandra J Kelly
- Department of Psychology, University of South Carolina, 1512 Pendleton St., Columbia, SC 29208, USA; Department of Pharmacology, Physiology, and Neuroscience, University of South Carolina School of Medicine, Columbia, SC 29208, USA.
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Karacay B, Mahoney J, Plume J, Bonthius DJ. Genetic absence of nNOS worsens fetal alcohol effects in mice. II: microencephaly and neuronal losses. Alcohol Clin Exp Res 2015; 39:221-31. [PMID: 25664654 DOI: 10.1111/acer.12615] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2014] [Accepted: 10/25/2014] [Indexed: 11/26/2022]
Abstract
BACKGROUND Prenatal alcohol exposure can kill developing neurons, leading to microencephaly and mental retardation. However, not all fetuses are equally vulnerable to alcohol's neurotoxic effects. While some fetuses are severely affected and are ultimately diagnosed with fetal alcohol syndrome (FAS), others have no evidence of neuropathology and are behaviorally normal. These widely different outcomes among alcohol-exposed fetuses are likely due, in part, to genetic differences. Some fetuses possess genotypes that make them much more vulnerable than others to alcohol's teratogenic effects. However, to date, only 1 gene has been identified whose mutation can worsen alcohol-induced behavioral deficits in an animal model of FAS. That gene is neuronal nitric oxide synthase (nNOS). The purpose of this study was to determine whether mutation of nNOS can likewise worsen alcohol-induced microencephaly and lead to permanent neuronal deficits. METHODS Wild-type and nNOS(-/-) mice received alcohol (0.0, 2.2, or 4.4 mg/g) daily over postnatal days (PDs) 4 to 9. Beginning on PD 85, the mice underwent a series of behavioral tests; the results of which are reported in the companion paper. The brains were then weighed, and stereological cell counts were performed on the cerebral cortex and hippocampal formation, which are the brain regions that mediate the aforementioned behavioral tasks. RESULTS Alcohol caused dose-dependent microencephaly, but only in the nNOS(-/-) mice and not in wild-type mice. Alcohol-induced neuronal losses were more severe in the nNOS(-/-) mice than in the wild-type mice in all of the brain regions examined, including the cerebral cortex, hippocampal CA3 subregion, hippocampal CA1 subregion, and dentate gyrus. CONCLUSIONS Targeted mutation of the nNOS gene increases the vulnerability of the developing brain to alcohol-induced growth restriction and neuronal losses. This increased neuropathology is associated with worsened behavioral dysfunction. The results demonstrate the critical importance of genotype in determining the outcome of developmental alcohol exposure.
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Affiliation(s)
- Bahri Karacay
- Department of Pediatrics , University of Iowa College of Medicine, Iowa City, Iowa
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Effect of folic acid in prenatal alcohol induced behavioral impairment in Swiss albino mice. Ann Neurosci 2014; 20:134-8. [PMID: 25206036 PMCID: PMC4117139 DOI: 10.5214/ans.0972.7531.200403] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2013] [Revised: 10/29/2013] [Accepted: 12/10/2013] [Indexed: 12/03/2022] Open
Abstract
Background Alcohol is a potent teratogen inducing oxidative stress as well as a massive wave of apoptosis in the developing brain as well as oxidative stress. It affects brain including cerebellum, hippocampus and cerebral cortex resulting into motor and cognitive deficits. Alcohol depletes folic acid from the body which is essential for synthesis of DNA, RNA and protein during cell division and proved to prevent many brain related malformations. Purpose The objective of the present study was to study whether folic acid reduces behavioral impairments that were induced by prenatal exposure to ethanol in mice. Methods Pregnant mice were divided into different experimental groups. Group I termed as control receiving distilled water, group II received ethanol, group III ethanol and folic acid and group IV folic acid only from gestational days 6 to 15. The dams were allowed to deliver their offspring naturally and until weaning the pups remained with their natural mothers. At the age of 8-9 weeks, they were subjected to battery of various behavioral tests. Results The alcohol exposed dams showed decreased motor activity in open field test and decreased exploration and increased anxiety in elevated maze test as compared to controls. Folic acid administration reduced the intensity of these effects of alcohol in mice. Conclusion The exposure to alcohol in utero produces long lasting effect on the developing pharmacological character of brain affecting postnatal behavioral expression which may be reduced by prenatal folic acid administration.
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The effects of black garlic ethanol extract on the spatial memory and estimated total number of pyramidal cells of the hippocampus of monosodium glutamate-exposed adolescent male Wistar rats. Anat Sci Int 2014; 90:275-86. [DOI: 10.1007/s12565-014-0262-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Accepted: 11/06/2014] [Indexed: 10/24/2022]
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Goodfellow MJ, Lindquist DH. Significant long-term, but not short-term, hippocampal-dependent memory impairment in adult rats exposed to alcohol in early postnatal life. Dev Psychobiol 2014; 56:1316-26. [PMID: 24691725 DOI: 10.1002/dev.21210] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2013] [Accepted: 01/27/2014] [Indexed: 12/14/2022]
Abstract
In rodents, ethanol exposure in early postnatal life is known to induce structural and functional impairments throughout the brain, including the hippocampus. Herein, rat pups were administered one of three ethanol doses over postnatal days (PD) 4-9, a period of brain development comparable to the third trimester of human pregnancy. As adults, control and ethanol rats were trained and tested in a variant of hippocampal-dependent one-trial context fear conditioning. In Experiment 1, subjects were placed into a novel context and presented with an immediate footshock (i.e., within ∼8 sec). When re-exposed to the same context 24 hr later low levels of conditioned freezing were observed. Context pre-exposure 24 hr prior to the immediate shock reversed the deficit in sham-intubated and unintubated control rats, enhancing freezing behavior during the context retention test. Even with context pre-exposure, however, significant dose-dependent reductions in contextual freezing were seen in ethanol rats. In Experiment 2, the interval between context pre-exposure and the immediate shock was shortened to 2 hr, in addition to the standard 24 hr. Ethanol rats trained with the 2 hr, but not 24 hr, interval displayed retention test freezing levels roughly equal to controls. Results suggest the ethanol rats can encode a short-term context memory and associate it with the aversive footshock 2 hr later. In the 24 hr ethanol rats the short-term context memory is poorly transferred or consolidated into long-term memory, we propose, impeding the memory's subsequent retrieval and association with shock.
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Affiliation(s)
- Molly J Goodfellow
- Department of Psychology, The Ohio State University, Columbus, OH, 43210
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Elibol-Can B, Dursun I, Telkes I, Kilic E, Canan S, Jakubowska-Dogru E. Examination of age-dependent effects of fetal ethanol exposure on behavior, hippocampal cell counts, and doublecortin immunoreactivity in rats. Dev Neurobiol 2013; 74:498-513. [PMID: 24302592 DOI: 10.1002/dneu.22143] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2013] [Revised: 10/11/2013] [Accepted: 10/24/2013] [Indexed: 11/10/2022]
Abstract
Ethanol is known as a potent teratogen having adverse effects on brain and behavior. However, some of the behavioral deficits caused by fetal alcohol exposure and well expressed in juveniles ameliorate with maturation may suggest some kind of functional recovery occurring during postnatal development. The aim of this study was to reexamine age-dependent behavioral impairments in fetal-alcohol rats and to investigate the changes in neurogenesis and gross morphology of the hippocampus during a protracted postnatal period searching for developmental deficits and/or delays that would correlate with behavioral impairments in juveniles and for potential compensatory processes responsible for their amelioration in adults. Ethanol was delivered to the pregnant dams by intragastric intubation throughout 7-21 gestation days at daily dose of 6 g/kg. Isocaloric intubation and intact control groups were included. Locomotor activity, anxiety, and spatial learning tasks were applied to juvenile and young-adult rats from all groups. Unbiased stereological estimates of hippocampal volumes, the total number of pyramidal and granular cells, and double cortin expressing neurons were carried out for postnatal days (PDs) PD1, PD10, PD30, and PD60. Alcohol insult during second trimester equivalent caused significant deficits in the spatial learning in juvenile rats; however, its effect on hippocampal morphology was limited to a marginally lower number of granular cells in dentate gyrus (DG) on PD30. Thus, initial behavioral deficits and the following functional recovery in fetal-alcohol subjects may be due to more subtle plastic changes within the hippocampal formation but also in other structures of the extended hippocampal circuit. Further investigation is required.
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Affiliation(s)
- Birsen Elibol-Can
- Department of Biological Sciences, Middle East Technical University, Ankara, 06531, Turkey
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Lee HJ, Ryu JS, Choi NY, Park YS, Kim YI, Han DW, Ko K, Shin CY, Hwang HS, Kang KS, Ko K. Transgenerational effects of paternal alcohol exposure in mouse offspring. Anim Cells Syst (Seoul) 2013. [DOI: 10.1080/19768354.2013.865675] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
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Cole GJ, Zhang C, Ojiaku P, Bell V, Devkota S, Mukhopadhyay S. Effects of ethanol exposure on nervous system development in zebrafish. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2013; 299:255-315. [PMID: 22959306 DOI: 10.1016/b978-0-12-394310-1.00007-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Alcohol (ethanol) is a teratogen that adversely affects nervous system development in a wide range of animal species. In humans numerous congenital abnormalities arise as a result of fetal alcohol exposure, leading to a spectrum of disorders referred to as fetal alcohol spectrum disorder (FASD). These abnormalities include craniofacial defects as well as neurological defects that affect a variety of behaviors. These human FASD phenotypes are reproduced in the rodent central nervous system (CNS) following prenatal ethanol exposure. While the study of ethanol effects on zebrafish development has been more limited, several studies have shown that different strains of zebrafish exhibit differential susceptibility to ethanol-induced cyclopia, as well as behavioral deficits. Molecular mechanisms underlying the effects of ethanol on CNS development also appear to be shared between rodent and zebrafish. Thus, zebrafish appear to recapitulate the observed effects of ethanol on human and mouse CNS development, indicating that zebrafish can serve as a complimentary developmental model system to study the molecular basis of FASD. Recent studies examining the effect of ethanol exposure on zebrafish nervous system development are reviewed, with an emphasis on attempts to elucidate possible molecular pathways that may be impacted by developmental ethanol exposure. Recent work from our laboratories supports a role for perturbed extracellular matrix function in the pathology of ethanol exposure during zebrafish CNS development. The use of the zebrafish model to assess the effects of ethanol exposure on adult nervous system function as manifested by changes in zebrafish behavior is also discussed.
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Affiliation(s)
- Gregory J Cole
- Julius L. Chambers Biomedical/Biotechnology Research Institute, North Carolina Central University, Durham, NC, USA
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Lindquist DH, Sokoloff G, Milner E, Steinmetz JE. Neonatal ethanol exposure results in dose-dependent impairments in the acquisition and timing of the conditioned eyeblink response and altered cerebellar interpositus nucleus and hippocampal CA1 unit activity in adult rats. Alcohol 2013; 47:447-57. [PMID: 23871534 DOI: 10.1016/j.alcohol.2013.05.007] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2012] [Revised: 03/24/2013] [Accepted: 05/15/2013] [Indexed: 10/26/2022]
Abstract
Exposure to ethanol in neonatal rats results in reduced neuronal numbers in the cerebellar cortex and deep nuclei of juvenile and adult animals. This reduction in cell numbers is correlated with impaired delay eyeblink conditioning (EBC), a simple motor learning task in which a neutral conditioned stimulus (CS; tone) is repeatedly paired with a co-terminating unconditioned stimulus (US; periorbital shock). Across training, cell populations in the interpositus (IP) nucleus model the temporal form of the eyeblink-conditioned response (CR). The hippocampus, though not required for delay EBC, also shows learning-dependent increases in CA1 and CA3 unit activity. In the present study, rat pups were exposed to 0, 3, 4, or 5 mg/kg/day of ethanol during postnatal days (PD) 4-9. As adults, CR acquisition and timing were assessed during 6 training sessions of delay EBC with a short (280 ms) interstimulus interval (ISI; time from CS onset to US onset) followed by another 6 sessions with a long (880 ms) ISI. Neuronal activity was recorded in the IP and area CA1 during all 12 sessions. The high-dose rats learned the most slowly and, with the moderate-dose rats, produced the longest CR peak latencies over training to the short ISI. The low dose of alcohol impaired CR performance to the long ISI only. The 3E (3 mg/kg/day of ethanol) and 5E (5 mg/kg/day of ethanol) rats also showed slower-than-normal increases in learning-dependent excitatory unit activity in the IP and CA1. The 4E (4 mg/kg/day of ethanol) rats showed a higher rate of CR production to the long ISI and enhanced IP and CA1 activation when compared to the 3E and 5E rats. The results indicate that binge-like ethanol exposure in neonatal rats induces long-lasting, dose-dependent deficits in CR acquisition and timing and diminishes conditioning-related neuronal excitation in both the cerebellum and hippocampus.
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Wagner JL, Klintsova AY, Greenough WT, Goodlett CR. Rehabilitation training using complex motor learning rescues deficits in eyeblink classical conditioning in female rats induced by binge-like neonatal alcohol exposure. Alcohol Clin Exp Res 2013; 37:1561-70. [PMID: 23647404 DOI: 10.1111/acer.12122] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2012] [Accepted: 01/22/2013] [Indexed: 02/04/2023]
Abstract
BACKGROUND Effective treatments for the behavioral and cognitive deficits in children with fetal alcohol spectrum disorders (FASD) are lacking, and translational approaches using animal models can help develop rational interventions. One such model, binge-like alcohol exposure in neonatal rats during the period of brain development comparable with that of the human third trimester, causes structural and functional damage to the cerebellum and disrupts cerebellar-dependent eyeblink classical conditioning. The eyeblink conditioning deficits first demonstrated in this rat model predicted the similar deficits subsequently demonstrated in children with FASD. METHODS The current study extends this translational approach by testing the hypothesis that rehabilitation training involving 20 days of training on traversal of an obstacle course (complex motor learning) would ameliorate the deficits on classical conditioning of eyeblink responses produced by the neonatal alcohol exposure. We have previously shown that this training stimulates cerebellar synaptic plasticity and improves alcohol-induced deficits on motor coordination tasks. RESULTS The current studies found that rehabilitation training significantly attenuated alcohol-induced deficits in acquisition of eyeblink conditioning in females but not in males. These results are consistent with normalization of cerebellar-dependent learning, at least in alcohol-exposed females. CONCLUSIONS These findings extend previous studies in this model suggesting that rehabilitation of adolescents with FASD using training with complex motor learning tasks could be effective in ameliorating functional impairments associated with cerebellar damage. Eyeblink classical conditioning deficits are now well documented in children with FASD and could serve as an evaluation measure to continue to develop therapeutic interventions such as complex motor learning.
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Affiliation(s)
- Jennifer L Wagner
- Department of Psychology , Indiana University Purdue University Indianapolis, Indianapolis, Indiana
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Perkins A, Lehmann C, Lawrence RC, Kelly SJ. Alcohol exposure during development: Impact on the epigenome. Int J Dev Neurosci 2013; 31:391-7. [PMID: 23542005 DOI: 10.1016/j.ijdevneu.2013.03.010] [Citation(s) in RCA: 71] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2012] [Revised: 03/15/2013] [Accepted: 03/16/2013] [Indexed: 02/08/2023] Open
Abstract
Fetal alcohol spectrum disorders represent a wide range of symptoms associated with in utero alcohol exposure. Animal models of FASD have been useful in determining the specific neurological consequences of developmental alcohol exposure, but the mechanisms of those consequences are unclear. Long-lasting changes to the epigenome are proposed as a mechanism of alcohol-induced teratogenesis in the hippocampus. The current study utilized a three-trimester rodent model of FASD to examine changes to some of the enzymatic regulators of the epigenome in adolescence. Combined pre- and post-natal alcohol exposureresulted in a significant increase in DNA methyltransferase activity (DNMT), without affecting histone deacetylase activity (HDAC). Developmental alcohol exposure also caused a change in gene expression of regulators of the epigenome, in particular, DNMT1, DNMT3a, and methyl CpG binding protein 2 (MeCP2). The modifications of the activity and expression of epigenetic regulators in the hippocampus of rodents perinatally exposed to alcohol suggest that alcohol's impact on the epigenome and its regulators may be one of the underlying mechanisms of alcohol teratogenesis.
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Affiliation(s)
- Amy Perkins
- Department of Psychology, University of South Carolina, Columbia, SC, 29208, United States.
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Effects of neonatal alcohol dose and exposure window on long delay and trace eyeblink conditioning in juvenile rats. Behav Brain Res 2013; 236:307-318. [DOI: 10.1016/j.bbr.2012.08.025] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2011] [Revised: 08/13/2012] [Accepted: 08/16/2012] [Indexed: 02/04/2023]
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Hippocampal-dependent Pavlovian conditioning in adult rats exposed to binge-like doses of ethanol as neonates. Behav Brain Res 2012; 242:191-9. [PMID: 23274841 DOI: 10.1016/j.bbr.2012.12.030] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2012] [Revised: 12/12/2012] [Accepted: 12/13/2012] [Indexed: 01/13/2023]
Abstract
Binge-like postnatal ethanol exposure produces significant damage throughout the brain in rats, including the cerebellum and hippocampus. In the current study, cue- and context-mediated Pavlovian conditioning were assessed in adult rats exposed to moderately low (3E; 3g/kg/day) or high (5E; 5g/kg/day) doses of ethanol across postnatal days 4-9. Ethanol-exposed and control groups were presented with 8 sessions of trace eyeblink conditioning followed by another 8 sessions of delay eyeblink conditioning, with an altered context presented over the last two sessions. Both forms of conditioning rely on the brainstem and cerebellum, while the more difficult trace conditioning also requires the hippocampus. The hippocampus is also needed to gate or modulate expression of the eyeblink conditioned response (CR) based on contextual cues. Results indicate that the ethanol-exposed rats were not significantly impaired in trace EBC relative to control subjects. In terms of CR topography, peak amplitude was significantly reduced by both doses of alcohol, whereas onset latency but not peak latency was significantly lengthened in the 5E rats across the latter half of delay EBC in the original training context. Neither dosage resulted in significant impairment in the contextual gating of the behavioral response, as revealed by similar decreases in CR production across all four treatment groups following introduction of the novel context. Results suggest ethanol-induced brainstem-cerebellar damage can account for the present results, independent of the putative disruption in hippocampal development and function proposed to occur following postnatal ethanol exposure.
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Kouzoukas DE, Li G, Takapoo M, Moninger T, Bhalla RC, Pantazis NJ. Intracellular calcium plays a critical role in the alcohol-mediated death of cerebellar granule neurons. J Neurochem 2012; 124:323-35. [PMID: 23121601 DOI: 10.1111/jnc.12076] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2012] [Revised: 09/30/2012] [Accepted: 10/10/2012] [Indexed: 11/28/2022]
Abstract
Alcohol is a potent neuroteratogen that can trigger neuronal death in the developing brain. However, the mechanism underlying this alcohol-induced neuronal death is not fully understood. Utilizing primary cultures of cerebellar granule neurons (CGN), we tested the hypothesis that the alcohol-induced increase in intracellular calcium [Ca(2+)](i) causes the death of CGN. Alcohol induced a dose-dependent (200-800 mg/dL) neuronal death within 24 h. Ratiometric Ca(2+) imaging with Fura-2 revealed that alcohol causes a rapid (1-2 min), dose-dependent increase in [Ca(2+)](i), which persisted for the duration of the experiment (5 or 7 min). The alcohol-induced increase in [Ca(2+)](i) was observed in Ca(2+) -free media, suggesting intracellular Ca(2+) release. Pre-treatment of CGN cultures with an inhibitor (2-APB) of the inositol-triphosphate receptor (IP(3) R), which regulates Ca(2+) release from the endoplasmic reticulum (ER), blocked both the alcohol-induced rise in [Ca(2+)](i) and the neuronal death caused by alcohol. Similarly, pre-treatment with BAPTA/AM, a Ca(2+) -chelator, also inhibited the alcohol-induced surge in [Ca(2+) ](i) and prevented neuronal death. In conclusion, alcohol disrupts [Ca(2+)](i) homeostasis in CGN by releasing Ca(2+) from intracellular stores, resulting in a sustained increase in [Ca(2+)](i). This sustained increase in [Ca(2+)](i) may be a key determinant in the mechanism underlying alcohol-induced neuronal death.
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Affiliation(s)
- Dimitrios E Kouzoukas
- Department of Anatomy and Cell Biology, Carver College of Medicine, The University of Iowa, Iowa City, IA, USA
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Early Postnatal Ethanol Exposure: Glutamatergic Excitotoxic Cell Death During Acute Withdrawal. NEUROPHYSIOLOGY+ 2012. [DOI: 10.1007/s11062-012-9308-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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Kane CJM, Phelan KD, Drew PD. Neuroimmune mechanisms in fetal alcohol spectrum disorder. Dev Neurobiol 2012; 72:1302-16. [PMID: 22623427 DOI: 10.1002/dneu.22035] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2012] [Accepted: 05/15/2012] [Indexed: 12/24/2022]
Abstract
Fetal alcohol spectrum disorder (FASD) is a major health concern worldwide and results from maternal consumption of alcohol during pregnancy. It produces tremendous individual, social, and economic losses. This review will first summarize the structural, functional, and behavior changes seen in FASD. The development of the neuroimmune system will be then be described with particular emphasis on the role of microglial cells in the normal regulation of homeostatic function in the central nervous system (CNS) including synaptic transmission. The impact of alcohol on the neuroimmune system in the developing CNS will be discussed in the context of several key immune molecules and signaling pathways involved in neuroimmune mechanisms that contribute to FASD. This review concludes with a summary of the development of early therapeutic approaches utilizing immunosuppressive drugs to target alcohol-induced pathologies. The significant role played by neuroimmune mechanisms in alcohol addiction and pathology provides a focus for future research aimed at understanding and treating the consequences of FASD.
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Affiliation(s)
- Cynthia J M Kane
- Department of Neurobiology and Developmental Sciences, University of Arkansas for Medical Sciences, Little Rock, Arkansas 72205, USA.
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Heaton MB, Siler-Marsiglio K, Paiva M, Kotler A, Rogozinski J, Kubovec S, Coursen M, Madorsky V. Ethanol influences on Bax associations with mitochondrial membrane proteins in neonatal rat cerebellum. Dev Neurobiol 2012; 73:127-41. [PMID: 22767450 DOI: 10.1002/dneu.22042] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2012] [Revised: 05/13/2012] [Accepted: 06/13/2012] [Indexed: 12/22/2022]
Abstract
These studies investigated interactions taking place at the mitochondrial membrane in neonatal rat cerebellum following ethanol exposure and focused on interactions between proapoptotic Bax and proteins of the permeability transition pore (PTP), voltage-dependent anion channel (VDAC) and adenine nucleotide translocator (ANT) of the outer and inner mitochondrial membranes, respectively. Cultured cerebellar granule cells were used to assess the role of these interactions in ethanol neurotoxicity. Analyses were made at the age of maximal cerebellar ethanol vulnerability (P4), compared to the later age of relative resistance (P7), to determine whether differential ethanol sensitivity was mirrored by differences in these molecular interactions. We found that, following ethanol exposure, Bax proapoptotic associations with both VDAC and ANT were increased, particularly at the age of greater ethanol sensitivity, and these interactions were sustained at this age for at least 2 h postexposure. Since Bax:VDAC interactions disrupt protective VDAC interactions with mitochondrial hexokinase (HXK), we also assessed VDAC:HXK associations following ethanol treatment and found such interactions were altered by ethanol treatment, but only at 2 h postexposure and only in the P4, ethanol-sensitive cerebellum. Ethanol neurotoxicity in cultured neuronal preparations was abolished by pharmacological inhibition of both VDAC and ANT interactions with Bax but not by a Bax channel blocker. Therefore, we conclude that, at this age, within the constraints of our experimental model, a primary mode of Bax-induced initiation of the apoptosis cascade following ethanol insult involves interactions with proteins of the PTP complex and not channel formation independent of PTP constituents.
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Affiliation(s)
- Marieta Barrow Heaton
- Department of Neuroscience, University of Florida College of Medicine, Gainesville, Florida 32610-0244, USA.
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Idrus NM, Napper RMA. Acute and long-term Purkinje cell loss following a single ethanol binge during the early third trimester equivalent in the rat. Alcohol Clin Exp Res 2012; 36:1365-73. [PMID: 22404759 DOI: 10.1111/j.1530-0277.2012.01743.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2011] [Accepted: 12/12/2011] [Indexed: 11/28/2022]
Abstract
BACKGROUND In the rat, binge-like ethanol (EtOH) exposure during the early neonatal period (a developmental period equivalent to the human third trimester) can result in a permanent deficit of cerebellar Purkinje cells (Pcells). However, the consequences of a moderate binge alcohol exposure on a single day during this postnatal period have not been established. This is an issue of importance as many pregnant women binge drink periodically at social drinking levels. This study aimed to identify both the acute and long-term effects of exposure to a single alcohol binge that achieved a mean peak blood EtOH concentration of approximately 250 mg/dl during early postnatal life using a rat model of fetal alcohol spectrum disorders. METHODS Acute apoptotic Pcell death 10 hours after a moderate dose binge EtOH exposure from postnatal days (PDs) 0 to 10 was assessed using active caspase-3 immunolabeling. Acute Pcell apoptosis was quantified in cerebellar vermal lobules I-X using the physical disector method. Long-term effects were assessed at PD 60 using stereological methods to determine total Pcell numbers in the vermis, lobule III, and lobule IX, following a moderate dose binge EtOH exposure at PDs 0, 2, or 4. RESULTS Acute apoptosis was induced by EtOH on PDs 1 to 8 in a time and lobular-dependent manner. For EtOH exposure on PD 2, significant long-term Pcell loss occurred in lobule III. EtOH exposure on PD 4 resulted in significant long-term Pcell loss throughout the entire vermis. CONCLUSIONS These results indicate that a single, early EtOH episode of moderate dose can create significant and permanent Pcell loss in the developing cerebellum.
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Affiliation(s)
- Nirelia M Idrus
- Department of Anatomy and Structural Biology, University of Otago, Dunedin, New Zealand
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Neonatal alcohol exposure and the hippocampus in developing male rats: effects on behaviorally induced CA1 c-Fos expression, CA1 pyramidal cell number, and contextual fear conditioning. Neuroscience 2012; 206:89-99. [PMID: 22285885 DOI: 10.1016/j.neuroscience.2012.01.006] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2011] [Revised: 11/30/2011] [Accepted: 01/04/2012] [Indexed: 12/13/2022]
Abstract
Rats exposed to a high binge-like dose of alcohol over postnatal days (PD) 4-9 show reductions in CA1 pyramidal cells and impairments on behavioral tasks that depend on the hippocampus. We first examined hippocampal c-Fos expression as a marker of neuronal activity in normally developing rats following different phases of the context preexposure facilitation effect (CPFE) paradigm (Experiment 1). During the CPFE, preexposure to the training context facilitates contextual conditioning to an immediate shock given on a subsequent occasion. We then examined the relationship between CPFE impairment, hippocampal cell loss, and c-Fos expression in rats exposed to alcohol over PD 4-9 (Experiment 2). Normally developing (Experiment 1), sham-intubated control (SI), and PD 4-9 alcohol-exposed (4.00 g and 5.25 g/kg/d; Experiment 2) juvenile male rats were trained on the CPFE. The CPFE occurs over three phases separated by 24 h. Starting on PD 31, rats were preexposed to Context A or Context B for 5 min. After 24 h, all rats received an immediate 1.5-mA foot shock in Context A. Finally, rats were tested for contextual conditioning in Context A on PD 33. Normally developing and SI rats preexposed to Context A showed enhanced contextual fear compared with those preexposed to Context B (Experiment 1) or alcohol-exposed rats preexposed to Context A (Experiment 2). Rats were sacrificed 2 h following different phases of the CPFE and processed for c-Fos immunohistochemistry (Experiments 1 and 2) and CA1 pyramidal cell quantification (Experiment 2). In Experiment 1, c-Fos positive (c-Fos+) cells in the dentate gyrus (DG) were consistently high among rats preexposed to Context A (Pre), Context B (No Pre), or sacrificed directly from their home cage (Home) and did not differ across CPFE phases. CA3 and CA1 c-Fos+ cells were highest during preexposure and decreased across training phases, with Group No Pre showing greater numbers of c-Fos+ cells during training than Group Pre and Controls. In Experiment 2, SI rats had greater numbers of CA1 c-Fos+ cells compared with alcohol-exposed rats, differing significantly from rats exposed to the high alcohol dose (5.25 g) over PD 4-9. Experiment 2 also revealed a linear decline in CA1 pyramidal cells across treatment groups, again with rats from the high-alcohol dose group showing significantly fewer CA1 pyramidal cells compared with SI. Our results reveal that context novelty may be a significant contributor to differential hippocampal c-Fos expression following different phases of the CPFE. In addition, lower levels of c-Fos+ cells in alcohol-exposed rats following preexposure may be related to general reductions in the number of CA1 pyramidal cells in these rats. The significant CPFE impairments in rats exposed to the lower alcohol dose (4.00 g), who show a 15% reduction in CA1 pyramidal cells compared with SI rats, highlight the sensitivity of the CPFE to hippocampal insult.
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Heaton MB, Paiva M, Kubovic S, Kotler A, Rogozinski J, Swanson E, Madorsky V, Posados M. Differential effects of ethanol on c-jun N-terminal kinase, 14-3-3 proteins, and Bax in postnatal day 4 and postnatal day 7 rat cerebellum. Brain Res 2011; 1432:15-27. [PMID: 22169498 DOI: 10.1016/j.brainres.2011.11.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2011] [Revised: 11/01/2011] [Accepted: 11/03/2011] [Indexed: 11/18/2022]
Abstract
These studies investigated ethanol effects on upstream cellular elements and interactions which contribute to Bax-related apoptosis in neonatal rat cerebellum at ages of peak ethanol sensitivity (postnatal day 4 [P4]), compared to later ages of relative resistance (P7). Analyses were made of basal levels of the pro-apoptotic c-jun N-terminal kinase (JNK), Bax, and the 14-3-3 anchoring proteins, as well as the responsiveness of these substances to ethanol at P4 versus P7. Dimerization of Bax with 14-3-3 was also investigated at the two ages following ethanol treatment, a process which sequesters Bax in the cytosol, thus inhibiting its mitochondrial translocation and disruption of the mitochondrial membrane potential. Cultured cerebellar granule cells were used to examine the protective potential of JNK inhibition on ethanol-mediated cell death. Basal levels of JNK were significantly higher at P4 than P7, but no differences in the other proteins were found. Activated JNK, and cytosolic and mitochondrially-translocated Bax were increased in P4 but not P7 animals following ethanol exposure, while protective 14-3-3 proteins were increased only at P7. Ethanol treatment resulted in decreases in Bax:14-3-3 heterodimers at P4, but not at P7. Inhibition of JNK activity in vitro provided partial protection against ethanol neurotoxicity. Thus, differential temporal vulnerability to ethanol in this CNS region correlates with differences in both levels of apoptosis-related substances (e.g., JNK), and differential cellular responsiveness, favoring apoptosis at the most sensitive age and survival at the resistant age. The upstream elements contributing to this vulnerability can be targets for future therapeutic strategies.
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Affiliation(s)
- Marieta Barrow Heaton
- Department of Neuroscience, University of Florida College of Medicine, USA; McKnight Brain Institute, USA.
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Akers KG, Kushner SA, Leslie AT, Clarke L, van der Kooy D, Lerch JP, Frankland PW. Fetal alcohol exposure leads to abnormal olfactory bulb development and impaired odor discrimination in adult mice. Mol Brain 2011; 4:29. [PMID: 21736737 PMCID: PMC3148973 DOI: 10.1186/1756-6606-4-29] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2011] [Accepted: 07/07/2011] [Indexed: 01/12/2023] Open
Abstract
Background Children whose mothers consumed alcohol during pregnancy exhibit widespread brain abnormalities and a complex array of behavioral disturbances. Here, we used a mouse model of fetal alcohol exposure to investigate relationships between brain abnormalities and specific behavioral alterations during adulthood. Results Mice drank a 10% ethanol solution throughout pregnancy. When fetal alcohol-exposed offspring reached adulthood, we used high resolution MRI to conduct a brain-wide screen for structural changes and found that the largest reduction in volume occurred in the olfactory bulbs. Next, we tested adult mice in an associative olfactory task and found that fetal alcohol exposure impaired discrimination between similar odors but left odor memory intact. Finally, we investigated olfactory bulb neurogenesis as a potential mechanism by performing an in vitro neurosphere assay, in vivo labeling of new cells using BrdU, and in vivo labeling of new cells using a transgenic reporter system. We found that fetal alcohol exposure decreased the number of neural precursor cells in the subependymal zone and the number of new cells in the olfactory bulbs during the first few postnatal weeks. Conclusions Using a combination of techniques, including structural brain imaging, in vitro and in vivo cell detection methods, and behavioral testing, we found that fetal alcohol exposure results in smaller olfactory bulbs and impairments in odor discrimination that persist into adulthood. Furthermore, we found that these abnormalities in olfactory bulb structure and function may arise from deficits in the generation of new olfactory bulb neurons during early postnatal development.
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Affiliation(s)
- Katherine G Akers
- Neurosciences and Mental Health, Hospital for Sick Children, and Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
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