A new Down syndrome rat model races forward.

Animal models of Down syndrome (DS) provide an essential resource for understanding genetic, cellular, and molecular contributions to traits associated with trisomy 21 (Ts21). Recent genetic enhancements in the development of DS models, including the new TcHSA21rat model (Kazuki et al.), have potential to transform our understanding of and potential therapies for Ts21.

Sex-specific developmental alterations in DYRK1A expression in the brain of a Down syndrome mouse model.

Aberrant neurodevelopment in Down syndrome (DS)-caused by triplication of human chromosome 21-is commonly attributed to gene dosage imbalance, linking overexpression of trisomic genes with disrupted developmental processes, with DYRK1A particularly implicated. We hypothesized that regional brain DYRK1A protein overexpression in trisomic mice varies over development in sex-specific patterns that may be distinct from Dyrk1a transcription, and reduction of Dyrk1a copy number from 3 to 2 in otherwise trisomic mice reduces DYRK1A, independent of other trisomic genes. DYRK1A overexpression varied with age, sex, and brain region, with peak overexpression on postnatal day (P) 6 in both sexes. Sex-dependent differences were also evident from P15-P24. Reducing Dyrk1a copy number confirmed that these differences depended on Dyrk1a gene dosage and not other trisomic genes. Trisomic Dyrk1a mRNA and protein expression were not highly correlated. Sex-specific patterns of DYRK1A overexpression during trisomic neurodevelopment may provide mechanistic targets for therapeutic intervention in DS.

Meta-Analyses of Externalizing Disorders: Genetics or Prenatal Alcohol Exposure?

BACKGROUND: Externalizing disorders are heritable precursors to alcohol dependence, common in children of alcoholics (COA), and in children with prenatal alcohol exposure (PAE). Pregnancies involving alcohol exposure sufficient to affect the fetus may involve women with genetic risk for alcohol dependence. We hypothesized that known PAE will increase the odds of having an externalizing disorder compared to COA. METHODS: The odds ratios of 3 externalizing disorders (attention-deficit hyperactivity disorder [ADHD], conduct disorder [CD], and oppositional defiant disorder [ODD]) were obtained for 2 domains: (i) PAE and (ii) COA, by estimating the logged odds ratio (LOR) for each study. Permutation tests were implemented to compare LORs for PAE versus COA studies within each disorder, including PAE versus an alcohol dependent (AD) mother and PAE versus an AD father. RESULTS: In PAE studies, the odds of ADHD and CD were elevated. Rates of all 3 disorders were elevated in COA studies. Permutation tests revealed that the mean LOR for ADHD was significantly higher in PAE studies compared to: COA (p = 0.01), AD mother (p < 0.05), and AD father (p = 0.03). No differences were found for ODD (p = 0.09) or CD (p = 0.21). CONCLUSIONS: These results provide compelling evidence of an increased risk of ADHD in those with PAE beyond that due to parental alcohol dependence or a genetic liability, consistent with a unique etiology most likely due to direct alcohol exposure during prenatal development.

Video-based data acquisition system for use in eye blink classical conditioning procedures in sheep.

Pavlovian eye blink conditioning (EBC) has been extensively studied in humans and laboratory animals, providing one of the best-understood models of learning in neuroscience. EBC has been especially useful in translational studies of cerebellar and hippocampal function. We recently reported a novel extension of EBC procedures for use in sheep, and now describe new advances in a digital video-based system. The system delivers paired presentations of conditioned stimuli (CSs; a tone) and unconditioned stimuli (USs; an air puff to the eye), or CS-alone "unpaired" trials. This system tracks the linear distance between the eyelids to identify blinks occurring as either unconditioned (URs) or conditioned (CRs) responses, to a resolution of 5 ms. A separate software application (Eye Blink Reviewer) is used to review and autoscore the trial CRs and URs, on the basis of a set of predetermined rules, permitting an operator to confirm (or rescore, if needed) the autoscore results, thereby providing quality control for accuracy of scoring. Learning curves may then be quantified in terms of the frequencies of CRs over sessions, both on trials with paired CS-US presentations and on CS-alone trials. The latency to CR onset, latency to CR peak, and occurrence of URs are also obtained. As we demonstrated in two example cases, this video-based system provides efficient automated means to conduct EBC in sheep and can facilitate fully powered studies with multigroup designs that involve paired and unpaired training. This can help extend new studies in sheep, a species well suited for translational studies of neurodevelopmental disorders resulting from gestational exposure to drugs, toxins, or intrauterine distress.

Arylsulfatase B modulates neurite outgrowth via astrocyte chondroitin-4-sulfate: dysregulation by ethanol.

In utero ethanol exposure causes fetal alcohol spectrum disorders, associated with reduced brain plasticity; the mechanisms of these effects are not well understood, particularly with respect to glial involvement. Astrocytes release factors that modulate neurite outgrowth. We explored the hypothesis that ethanol inhibits neurite outgrowth by increasing the levels of inhibitory chondroitin sulfate proteoglycans (CSPGs) in astrocytes. Astrocyte treatment with ethanol inhibited the activity of arylsulfatase B (ARSB), the enzyme that removes sulfate groups from chondroitin-4-sulfate (C4S) and triggers the degradation of C4S, increased total sulfated glycosaminoglycans (GAGs), C4S, and neurocan core-protein content and inhibited neurite outgrowth in neurons cocultured with ethanol-treated astrocytes in vitro, effects reversed by treatment with recombinant ARSB. Ethanol also inhibited ARSB activity and increased sulfate GAG and neurocan levels in the developing hippocampus after in vivo ethanol exposure. ARSB silencing increased the levels of sulfated GAGs, C4S, and neurocan in astrocytes and inhibited neurite outgrowth in cocultured neurons, indicating that ARSB activity directly regulates C4S and affects neurocan expression. In summary, this study reports two major findings: ARSB modulates sulfated GAG and neurocan levels in astrocytes and astrocyte-mediated neurite outgrowth in cocultured neurons; and ethanol inhibits the activity of ARSB, increases sulfated GAG, C4S, and neurocan levels, and thereby inhibits astrocyte-mediated neurite outgrowth. An unscheduled increase in CSPGs in the developing brain may lead to altered brain connectivity and to premature decrease in neuronal plasticity and therefore represents a novel mechanism by which ethanol can exert its neurodevelopmental effects.

Rehabilitation training using complex motor learning rescues deficits in eyeblink classical conditioning in female rats induced by binge-like neonatal alcohol exposure.

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.

Housing in environmental complexity following wheel running augments survival of newly generated hippocampal neurons in a rat model of binge alcohol exposure during the third trimester equivalent.

BACKGROUND: Binge-like alcohol exposure in neonatal rats during the brain growth spurt causes deficits in adult neurogenesis in the hippocampal dentate gyrus (DG). Previous data from our laboratory demonstrated that 12 days of voluntary wheel running (WR) beginning on postnatal day (PD) 30 significantly increased the number of newly generated cells evident in the DG on PD42 in both alcohol-exposed (AE) and control rats, but 30 days later a sustained beneficial effect of WR was evident only in control rats. This study tested the hypothesis that housing rats in environmental complexity (EC) following WR would promote the survival of the newly generated cells stimulated by WR, particularly in AE rats. METHODS: On PD4 to 9, pups were intubated with alcohol in a binge-like manner (5.25 g/kg/d), sham-intubated (SI), or reared normally. In Experiment 1, animals were either assigned to WR during PD30 to 42 or socially housed (SH). On PD42, animals were injected with bromodeoxyuridine (BrdU; 200 mg/kg) and perfused 2 hours later to confirm the WR-induced stimulation of proliferation. In Experiment 2, all animals received WR on PD30 to 42 and were injected with BrdU on the last full day of WR. On PD42, animals were randomly assigned either to EC (WR/EC) or to SH (WR/SH) for 30 days and subsequently perfused and brains were processed for immunohistochemical staining to identify BrdU+-, Ki67+-, and BrdU+/NeuN+-labeled cells in DG. RESULTS: In Experiment 1, WR exposure significantly increased the number of proliferating cells in all 3 postnatal conditions. In Experiment 2, the AE rats given WR/SH had significantly fewer BrdU+ cells compared with control rats given WR/SH. However, WR/EC experience significantly increased the number of surviving BrdU+ cells in both the AE and SI groups compared with WR/SH rats of the same neonatal treatment. Approximately 80% of the surviving BrdU+ cells in the DG across the conditions were colabeled with NeuN. CONCLUSIONS: WR followed by EC could provide a behavioral model for developing interventions in humans to ameliorate hippocampal-dependent impairments associated with fetal alcohol spectrum disorders.

T-maze learning in weanling lambs.

A major advantage of sheep models in experimental studies of neurodevelopmental disorders (e.g., with prenatal neurotoxicant exposure) is that the equivalent of all three trimesters of human brain development occurs in sheep entirely in utero. However, studies of learning and memory in sheep are limited. The goal of this study was to extend the analysis of spatial learning and memory in adolescent sheep using several traditional T-maze tasks. Both 9- and 14-week-old lambs acquired a delayed nonmatching-to-place task, but the older lambs learned the task significantly faster. In contrast, acquisition of a matching-to-place task was significantly more difficult. Lambs, like rodents, appear to have a predisposition toward learning "win-shift" spatial problems in a T-maze under appetitive motivation. Lambs also rapidly acquired a position habit and showed typical reversal learning curves. These findings support the use of T-maze tasks to assess behavioral outcomes in various sheep models.

The effects of gestational choline supplementation on cerebellar Purkinje cell number in the sheep model of binge alcohol exposure during the first trimester-equivalent.

Individuals with fetal alcohol spectrum disorders (FASD) incur enduring brain damage and neurodevelopmental impairments from prenatal alcohol exposure (PAE). Preclinical rodent models have demonstrated that choline supplementation during development can reduce the severity of adverse neurodevelopmental consequences of PAE. This study used the sheep model to evaluate dietary choline supplementation during pregnancy as a therapeutic intervention, testing the hypothesis that choline can ameliorate alcohol-induced cerebellar Purkinje cell loss. Pregnant ewes were randomly assigned either to a normal control [NC] group (n = 8), or to groups given intravenous infusions of alcohol (or saline) from gestational days 4-41 (the first trimester-equivalent). A weekly binge-drinking pattern was modeled, with three consecutive days of infusions of saline [SAL], 1.75 g/kg/day alcohol [1.75ALC], or 2.5 g/kg/day alcohol [2.5ALC] followed by four days off. Infused ewes were randomly assigned to receive dietary supplements throughout pregnancy of choline (10 mg/kg/day) or placebo (n = 8 per group). Mean blood alcohol concentrations (BAC) were significantly higher in the 2.5ALC groups (287 mg/dL) than the 1.75ALC groups (197 mg/dL). Lamb cerebella were harvested on postnatal day 180 and processed for stereological counts of Purkinje cells. Both alcohol doses caused significant reductions in Purkinje number relative to NC and SAL-Placebo groups, confirming previous findings. Effects of choline supplementation depended on infusion group: it significantly protected against Purkinje cell loss in the 2.5ALC group, had no effect in the 1.75ALC group, and significantly reduced numbers in the SAL-Choline group (though neither the SAL-Choline nor the SAL-Placebo group differed from the NC group). The protection by choline evident only in the 2.5ALC group suggests that multiple, BAC-dependent mechanisms of cerebellar damage may be activated with alcohol exposure in the first trimester, and that choline may protect against pathogenic mechanisms that emerge at higher BACs. These outcomes extend the evidence that early choline supplementation can mitigate some neurodevelopmental defects resulting from binge-like PAE.

Sexually dimorphic DYRK1A overexpression on postnatal day 15 in the Ts65Dn mouse model of Down syndrome: Effects of pharmacological targeting on behavioral phenotypes.

The neurotypical spatiotemporal patterns of gene expression are disrupted in Down syndrome (DS) by trisomy of human chromosome 21 (Hsa21), resulting in altered behavioral development and brain circuitry. The Ts65Dn DS mouse model exhibits similar phenotypes to individuals with DS due to three copies of approximately one-half of the genes found on Hsa21. Dual-specificity Tyrosine Phosphorylation-regulated Kinase 1a (Dyrk1a), one of these triplicated genes, is an attractive target to normalize brain development due to its influence in cellular brain deficits seen in DS. We hypothesized that postnatal development of DYRK1A expression is dysregulated in trisomic animals, and found significant overexpression of DYRK1A in the hippocampus, cerebral cortex, and cerebellum at postnatal day (P) 15 in male-but not female-Ts65Dn mice. We then hypothesized the existence of sex-dependent effects of trisomy on neurobehavioral attributes during P16-17, and that administration of a DYRK1A inhibitor (CX-4945, ~75 mg/kg) beginning on P14 would normalize aberrant behavior in trisomic animals. Both male and female trisomic mice given control injections of phosphate buffered saline (PBS) displayed sustained levels of locomotor activity over a 10-minute test in contrast to the PBS-treated euploid animals that showed significant within-session habituation. Trisomic animals were more persistent in choosing to remain in home shavings in a preference test. Treatment with CX-4945 failed to confirm therapeutic effects. CX-4945 prevented growth, and both CX-4945 and its 10% dimethyl sulfoxide vehicle affected locomotor activity in trisomic and euploid groups, indicating a non-specific disruption of behavior. Despite the negative outcomes for CX-4945, the novel demonstration of sexually dimorphic DYRK1A expression in trisomic animals at P15 supports the broader hypothesis that overexpression of trisomic genes in DS can vary with age, sex, and brain region. Identifying the developmental timing of periods of dysregulated DYRK1A may be important for understanding individual differences in neurodevelopmental trajectories in DS and for developing effective therapeutic interventions targeting DYRK1A.

Alteration of gene expression by alcohol exposure at early neurulation.

BACKGROUND: We have previously demonstrated that alcohol exposure at early neurulation induces growth retardation, neural tube abnormalities, and alteration of DNA methylation. To explore the global gene expression changes which may underline these developmental defects, microarray analyses were performed in a whole embryo mouse culture model that allows control over alcohol and embryonic variables. RESULT: Alcohol caused teratogenesis in brain, heart, forelimb, and optic vesicle; a subset of the embryos also showed cranial neural tube defects. In microarray analysis (accession number GSM9545), adopting hypothesis-driven Gene Set Enrichment Analysis (GSEA) informatics and intersection analysis of two independent experiments, we found that there was a collective reduction in expression of neural specification genes (neurogenin, Sox5, Bhlhe22), neural growth factor genes [Igf1, Efemp1, Klf10 (Tieg), and Edil3], and alteration of genes involved in cell growth, apoptosis, histone variants, eye and heart development. There was also a reduction of retinol binding protein 1 (Rbp1), and de novo expression of aldehyde dehydrogenase 1B1 (Aldh1B1). Remarkably, four key hematopoiesis genes (glycophorin A, adducin 2, beta-2 microglobulin, and ceruloplasmin) were absent after alcohol treatment, and histone variant genes were reduced. The down-regulation of the neurospecification and the neurotrophic genes were further confirmed by quantitative RT-PCR. Furthermore, the gene expression profile demonstrated distinct subgroups which corresponded with two distinct alcohol-related neural tube phenotypes: an open (ALC-NTO) and a closed neural tube (ALC-NTC). Further, the epidermal growth factor signaling pathway and histone variants were specifically altered in ALC-NTO, and a greater number of neurotrophic/growth factor genes were down-regulated in the ALC-NTO than in the ALC-NTC embryos. CONCLUSION: This study revealed a set of genes vulnerable to alcohol exposure and genes that were associated with neural tube defects during early neurulation.

Strain differences in developmental vulnerability to alcohol exposure via embryo culture in mice.

BACKGROUND: Prenatal alcohol exposure can result in varying degrees of neurodevelopmental deficits, growth retardation, and facial dysmorphology. Variation in these adverse outcomes not only depends on the dose and pattern of alcohol exposure but also on less well understood interactions among environmental, genetic, and maternal factors. The current study tested the hypothesis that fetal genotype is an important determinant of ethanol teratogenesis by evaluating effects of ethanol exposure via embryo culture in 3 inbred strains of mice known to differ in the vulnerability of prenatal alcohol exposure in vivo. METHODS: Three strains of mice, C57BL/6N (B6), DBA/2 (D2), and 129S6/SvEvTac (129S6) were assessed in a whole embryo culture beginning on embryonic day 8.25, with or without alcohol administration at 88 mM for 6 hours followed by 42 hours culture in ethanol-free media. RESULTS: Contrasting strain differences in susceptibility were observed for the brain, the face, and other organ systems using the Maele-Fabry and Picard scoring system. The forebrain, midbrain, hindbrain, heart, optic vesicle, caudal neural tube, and hindlimbs of the B6 mice were severely delayed in growth, whereas compared to the respective controls, only the forebrain and optic vesicle were delayed in the D2 mice, and no effects were found in the 129S6 mice. A large number of cleaved (c)-caspase 3 positive (+) cells were found in regions of the brain, optic vesicles, cranial nerve nuclei V, VII, VIII, and IX as well as the craniofacial primordial; only a few were found in corresponding regions of the B6 controls. In contrast, only a small number of c-caspase 3 immunostaining cells were found in either the alcohol treated or the controls of the D2 embryos and in 129S6 embryos. The independent apoptotic markers TUNEL and Nile blue staining further confirmed the strain differences in apoptotic responses in both the neural tube and craniofacial primordia. CONCLUSIONS: Under embryo culture conditions, in which alcohol exposure factors and fetal developmental staging were controlled, and maternal and intrauterine factors were eliminated, the degree of growth retardation and the extent and type of neurodevelopmental teratogenesis varied significantly across strains. Notably, the 129S6 strain was remarkably resistant to alcohol-induced growth deficits, confirming a previous in vivo study, and the D2 strain was also significantly less affected than the B6 strain. These findings demonstrate that fetal genotype is an important factor that can contribute to the variation in fetal alcohol spectrum disorder.

Understanding ethanol's acute effects on medial prefrontal cortex neural activity using state-space approaches.

Acute ethanol (EtOH) intoxication results in several maladaptive behaviors that may be attributable, in part, to the effects of EtOH on neural activity in medial prefrontal cortex (mPFC). The acute effects of EtOH on mPFC function have been largely described as inhibitory. However, translating these observations on function into a mechanism capable of delineating acute EtOH's effects on behavior has proven difficult. This review highlights the role of acute EtOH on electrophysiological measurements of mPFC function and proposes that interpreting these changes through the lens of dynamical systems theory is critical to understand the mechanisms that mediate the effects of EtOH intoxication on behavior. Specifically, the present review posits that the effects of EtOH on mPFC N-methyl-d-aspartate (NMDA) receptors are critical for the expression of impaired behavior following EtOH consumption. This hypothesis is based on the observation that recurrent activity in cortical networks is supported by NMDA receptors, and, when disrupted, may lead to impairments in cognitive function. To evaluate this hypothesis, we discuss the representation of mPFC neural activity in low-dimensional, dynamic state spaces. This approach has proven useful for identifying the underlying computations necessary for the production of behavior. Ultimately, we hypothesize that EtOH-related alterations to NMDA receptor function produces alterations that can be effectively conceptualized as impairments in attractor dynamics and provides insight into how acute EtOH disrupts forms of cognition that rely on mPFC function. This article is part of the special Issue on 'Neurocircuitry Modulating Drug and Alcohol Abuse'.

Influence of allelic differences in Down syndrome.

Both trisomic and non-trisomic genes may affect the incidence and severity of phenotypes associated with Down syndrome (DS). The importance of extra (trisomic) genetic material is emphasized in DS, with less emphasis to the allelic composition of candidate trisomic genes in defining the trisomic gene-phenotype relationship in DS. Allelic differences in non-trisomic genes have been shown to be important moderators of cardiac, leukemia, and developmental phenotypes associated with DS. Trisomic mouse models provide an in vivo genetic platform for examining the gene-phenotype relationship, including the influence of allelic variants, on DS-like phenotypes. DS mouse models have differing trisomic genetic makeup, and optimal development, viability and translational value of these mouse models may require a non-inbred genetic background with heterogeneity at many loci. Additionally, understanding the contribution of specific genes or regions to DS phenotypes often requires the utilization of genetically manipulated mice that may be established on a different inbred background than the trisomic mice. The impact of allelic differences of trisomic and background genes in human and model systems may offer insight into the variability in occurrence and severity of trisomic phenotypes.

Behavioral Phenotyping for Down Syndrome in Mice.

Down syndrome (DS) is the most frequent genetic cause of intellectual disability, characterized by alterations in different behavioral symptom domains: neurodevelopment, motor behavior, and cognition. As mouse models have the potential to generate data regarding the neurological basis for the specific behavioral profile of DS, and may indicate pharmacological treatments with the potential to affect their behavioral phenotype, it is important to be able to assess disease-relevant behavioral traits in animal models in order to provide biological plausibility to the potential findings. The field is at a juncture that requires assessments that may effectively translate the findings acquired in mouse models to humans with DS. In this article, behavioral tests are described that are relevant to the domains affected in DS. A neurodevelopmental behavioral screen, the balance beam test, and the Multivariate Concentric Square Field test to assess multiple behavioral phenotypes and locomotion are described, discussing the ways to merge these findings to more fully understand cognitive strengths and weaknesses in this population. New directions for approaches to cognitive assessment in mice and humans are discussed. © 2020 Wiley Periodicals LLC. Basic Protocol 1: Preweaning neurodevelopmental battery Basic Protocol 2: Balance beam Basic Protocol 3: Multivariate concentric square field test (MCSF).

Evaluation of the therapeutic potential of Epigallocatechin-3-gallate (EGCG) via oral gavage in young adult Down syndrome mice.

Epigallocatechin-3-gallate (EGCG) is a candidate therapeutic for Down syndrome (DS) phenotypes based on in vitro inhibition of DYRK1A, a triplicated gene product of Trisomy 21 (Ts21). Consumption of green tea extracts containing EGCG improved some cognitive and behavioral outcomes in DS mouse models and in humans with Ts21. In contrast, treatment with pure EGCG in DS mouse models did not improve neurobehavioral phenotypes. This study tested the hypothesis that 200 mg/kg/day of pure EGCG, given via oral gavage, would improve neurobehavioral and skeletal phenotypes in the Ts65Dn DS mouse model. Serum EGCG levels post-gavage were significantly higher in trisomic mice than in euploid mice. Daily EGCG gavage treatments over three weeks resulted in growth deficits in both euploid and trisomic mice. Compared to vehicle treatment, EGCG did not significantly improve behavioral performance of Ts65Dn mice in the multivariate concentric square field, balance beam, or Morris water maze tasks, but reduced swimming speed. Furthermore, EGCG resulted in reduced cortical bone structure and strength in Ts65Dn mice. These outcomes failed to support the therapeutic potential of EGCG, and the deleterious effects on growth and skeletal phenotypes underscore the need for caution in high-dose EGCG supplements as an intervention in DS.

Acute alcohol and cognition: Remembering what it causes us to forget.

Addiction has been conceptualized as a specific form of memory that appropriates typically adaptive neural mechanisms of learning to produce the progressive spiral of drug-seeking and drug-taking behavior, perpetuating the path to addiction through aberrant processes of drug-related learning and memory. From that perspective, to understand the development of alcohol use disorders, it is critical to identify how a single exposure to alcohol enters into or alters the processes of learning and memory, so that involvement of and changes in neuroplasticity processes responsible for learning and memory can be identified early. This review characterizes the effects produced by acute alcohol intoxication as a function of brain region and memory neurocircuitry. In general, exposure to ethanol doses that produce intoxicating effects causes consistent impairments in learning and memory processes mediated by specific brain circuitry, whereas lower doses either have no effect or produce a facilitation of memory under certain task conditions. Therefore, acute ethanol does not produce a global impairment of learning and memory, and can actually facilitate particular types of memory, perhaps particular types of memory that facilitate the development of excessive alcohol use. In addition, the effects on cognition are dependent on brain region, task demands, dose received, pharmacokinetics, and tolerance. Additionally, we explore the underlying alterations in neurophysiology produced by acute alcohol exposure that help to explain these changes in cognition and highlight future directions for research. Through understanding the impact that acute alcohol intoxication has on cognition, the preliminary changes potentially causing a problematic addiction memory can better be identified.

Usage of and attitudes about green tea extract and Epigallocathechin-3-gallate (EGCG) as a therapy in individuals with Down syndrome.

OBJECTIVE: Usage of and views concerning alternative therapies in the DS community are not well documented. Some positive effects of green tea extracts (GTE) containing Epigallocathechin-3-gallate (EGCG) have been reported in individuals with DS and DS mouse models, but minimal improvements or detrimental effects of pure EGCG treatment have been reported in DS mouse models. Given the uncertainty about the effectiveness of these supplements, the goal of this study was to determine the relative prevalence of and attitudes about GTE/EGCG treatments among DS caregivers. METHODS: An anonymous survey about attitudes and usage of GTE/EGCG in individuals with DS was completed by caregivers of these individuals. RESULTS: GTE/EGCG treatment was provided by 18% of responding caregivers who were mostly younger, highly educated, and utilized scientific sources and other parents to influence their decision to use GTE/EGCG. Individuals with DS who received GTE/EGCG were characterized as less severely disabled. Most caregivers who did not give GTE/EGCG reported concerns about potential side effects and lack of effectiveness. Few caregivers consulted with medical providers about GTE/EGCG usage. CONCLUSIONS: These results demonstrate a need for communication between caregivers, medical providers, and scientists about potential benefits and risks for adverse effects of GTE, EGCG, and other nutritional supplements in individuals with DS.

Maternal choline supplementation mitigates alcohol-induced fetal cranio-facial abnormalities detected using an ultrasonographic examination in a sheep model.

Early detection of prenatal alcohol exposure is critical for designing and testing effectiveness of interventional therapeutics. Choline supplementation during and after prenatal alcohol exposure has shown promising benefits in improving outcomes in rodent models and clinical studies. A sheep model of first trimester-equivalent binge alcohol exposure was used in this study to model the dose of maternal choline supplementation used in an ongoing prospective clinical trial involving pregnancies at risk for FASD. Pregnant sheep were randomly assigned to six groups: Saline + Placebo control, Saline + Choline, binge Alcohol + Placebo (light binging), binge Alcohol + Choline, Heavy binge Alcohol + Placebo (heavy binging), and Heavy binge Alcohol + Choline. Ewes received intravenous alcohol or saline on three consecutive days per week from gestation day (GD) 4-41 to mimic a first trimester-equivalent weekend binge-drinking paradigm. Choline (10 mg/kg in the daily food ration) was administered from GD 4 until term. On GD 76, 11 fetal ultrasonographic measurements were collected transabdominally. Heavy binge alcohol exposure reduced fetal Frontothalamic Distance (FTD), Mean Orbital Diameter (MOD), and Mean Lens Diameter (MLD), and increased Interorbital Distance (IOD) and Thalamic Width (TW). Maternal choline supplementation mitigated most of these alcohol-induced effects. Maternal choline supplementation also improved overall fetal femur and humerus bone lengths, compared to their respective placebo groups. Taken together, these results indicate a potential dose-dependent effect that could impact the sensitivity of these ultrasonographic measures in predicting prenatal alcohol exposure. This is the first study in the sheep model to identify biomarkers of prenatal alcohol exposure in utero with ultrasound and co-administration of maternal choline supplementation.

Eyeblink classical conditioning in the preweanling lamb.

Classical conditioning of eyeblink responses has been one of the most important models for studying the neurobiology of learning, with many comparative, ontogenetic, and clinical applications. The current study reports the development of procedures to conduct eyeblink conditioning in preweanling lambs and demonstrates successful conditioning using these procedures. These methods will permit application of eyeblink conditioning procedures in the analysis of functional correlates of cerebellar damage in a sheep model of fetal alcohol spectrum disorders, which has significant advantages over more common laboratory rodent models. Because sheep have been widely used for studies of pathogenesis and mechanisms of injury with many different prenatal or perinatal physiological insults, eyeblink conditioning can provide a well-studied method to assess postnatal behavioral outcomes, which heretofore have not typically been pursued with ovine models of developmental insults.