The importance of alcohol misuse, malnutrition and genetic susceptibility on brain growth and plasticity

Impaired hippocampal neurogenesis in vitro is modulated by dietary-related endogenous factors and associated with depression in a longitudinal ageing cohort study

Environmental factors like diet have been linked to depression and/or relapse risk in later life. This could be partially driven by the food metabolome, which communicates with the brain via the circulatory system and interacts with hippocampal neurogenesis (HN), a form of brain plasticity implicated in depression aetiology. Despite the associations between HN, diet and depression, human data further substantiating this hypothesis are largely missing. Here, we used an in vitro model of HN to test the effects of serum samples from a longitudinal ageing cohort of 373 participants, with or without depressive symptomology. 1% participant serum was applied to human fetal hippocampal progenitor cells, and changes in HN markers were related to the occurrence of depressive symptoms across a 12-year period. Key nutritional, metabolomic and lipidomic biomarkers (extracted from participant plasma and serum) were subsequently tested for their ability to modulate HN. In our assay, we found that reduced cell death and increased neuronal differentiation were associated with later life depressive symptomatology. Additionally, we found impairments in neuronal cell morphology in cells treated with serum from participants experiencing recurrent depressive symptoms across the 12-year period. Interestingly, we found that increased neuronal differentiation was modulated by increased serum levels of metabolite butyrylcarnitine and decreased glycerophospholipid, PC35:1(16:0/19:1), levels - both of which are closely linked to diet - all in the context of depressive symptomology. These findings potentially suggest that diet and altered HN could subsequently shape the trajectory of late-life depressive symptomology.

The Effects of Alcohol and Drugs of Abuse on Maternal Nutritional Profile during Pregnancy

The consumption of alcohol and drugs of abuse among pregnant women has experienced a significant increase in the last decades. Suitable maternal nutritional status is crucial to maintain the optimal environment for fetal development but if consumption of alcohol or drugs of abuse disrupt the intake of nutrients, the potential teratogenic effects of these substances increase. Despite evidence of the importance of nutrition in addicted pregnant women, there is a lack of information on the effects of alcohol and drugs of abuse on maternal nutritional status; so, the focus of this review was to provide an overview on the nutritional status of addicted mothers and fetuses. Alcohol and drugs consumption can interfere with the absorption of nutrients, impairing the quality and quantity of proper nutrient and energy intake, resulting in malnutrition especially of micronutrients (vitamins, omega⁻3, folic acid, zinc, choline, iron, copper, selenium). When maternal nutritional status is compromised by alcohol and drugs of abuse the supply of essential nutrients are not available for the fetus; this can result in fetal abnormalities like Intrauterine Growth Restriction (IUGR) or Fetal Alcohol Spectrum Disorder (FASD). It is critical to find a strategy to reduce fetal physical and neurological impairment as a result of prenatal alcohol and drugs of abuse exposure combined with poor maternal nutrition. Prenatal nutrition interventions and target therapy are required that may reverse the development of such abnormalities.

Thiamin deficiency on fetal brain development with and without prenatal alcohol exposure

Adequate thiamin levels are crucial for optimal health through maintenance of homeostasis and viability of metabolic enzymes, which require thiamine as a co-factor. Thiamin deficiency occurs during pregnancy when the dietary intake is inadequate or excessive alcohol is consumed. Thiamin deficiency leads to brain dysfunction because thiamin is involved in the synthesis of myelin and neurotransmitters (e.g., acetylcholine, γ-aminobutyric acid, glutamate), and its deficiency increases oxidative stress by decreasing the production of reducing agents. Thiamin deficiency also leads to neural membrane dysfunction, because thiamin is a structural component of mitochondrial and synaptosomal membranes. Similarly, in-utero exposure to alcohol leads to fetal brain dysfunction, resulting in negative effects such as fetal alcohol spectrum disorder (FASD). Thiamin deficiency and prenatal exposure to alcohol could act synergistically to produce negative effects on fetal development; however, this area of research is currently under-studied. This minireview summarizes the evidence for the potential role of thiamin deficiency in fetal brain development, with or without prenatal exposure to alcohol. Such evidence may influence the development of new nutritional strategies for preventing or mitigating the symptoms of FASD.

Postnatal nutritional treatment of neurocognitive deficits in fetal alcohol spectrum disorder

Ethanol is the most important teratogen agent in humans. Prenatal alcohol exposure can lead to a wide range of adverse effects, which are broadly termed as fetal alcohol spectrum disorder (FASD). The most severe consequence of maternal alcohol abuse is the development of fetal alcohol syndrome, defined by growth retardation, facial malformations, and central nervous system impairment expressed as microcephaly and neurodevelopment abnormalities. These alterations generate a broad range of cognitive abnormalities such as learning disabilities and hyperactivity and behavioural problems. Socioeconomic status, ethnicity, differences in genetic susceptibility related to ethanol metabolism, alcohol consumption patterns, obstetric problems, and environmental influences like maternal nutrition, stress, and other co-administered drugs are all factors that may influence FASD manifestations. Recently, much attention has been paid to the role of nutrition as a protective factor against alcohol teratogenicity. There are a great number of papers related to nutritional treatment of nutritional deficits due to several factors associated with maternal consumption of alcohol and with eating and social disorders in FASD children. Although research showed the clinical benefits of nutritional interventions, most of work was in animal models, in a preclinical phase, or in the prenatal period. However, a minimum number of studies refer to postnatal nutrition treatment of neurodevelopmental deficits. Nutritional supplementation in children with FASD has a dual objective: to overcome nutritional deficiencies and to reverse or improve the cognitive deleterious effects of prenatal alcohol exposure. Further research is necessary to confirm positive results, to determine optimal amounts of nutrients needed in supplementation, and to investigate the collective effects of simultaneous multiple-nutrient supplementation.

Etiological Subgroups of Small-for-Gestational-Age: Differential Neurodevelopmental Outcomes

Objectives

It remains unclear why substantial variations in neurodevelopmental outcomes exist within small-for-gestational-age (SGA) children. We prospectively compared 5-y neurodevelopmental outcomes across SGA etiological subgroups.

Methods

Children born SGA (N = 1050) from U.S. Early Childhood Longitudinal Study-Birth Cohort (2001–2007) was divided into etiological subgroups by each of 7 well-established prenatal risk factors. We fit linear regression models to compare 5-y reading, math, gross motor and fine motor scores across SGA subgroups, adjusting for socio-demographic confounders.

Results

Compared to singleton SGA subgroup, multiple-birth SGA subgroup had lower mean reading (adjusted mean difference, -4.08 [95% confidence interval, -6.10, -2.06]) and math (-2.22 [-3.61, -0.84]) scores. These disadvantages in reading and math existed only among multiple-birth SGA subgroup without ovulation stimulation (reading, -4.50 [-6.64, -2.36]; math, -2.91 [-4.37, -1.44]), but not among those with ovulation stimulation (reading, -2.33 [-6.24, 1.57]; math 0.63 [-1.86, 3.12]). Compared to singleton SGA subgroup without maternal smoking and inadequate gestational weight gain, singleton SGA subgroup with co-occurrence of maternal smoking and inadequate gestational weight gain (GWG) had lower mean reading (-4.81 [-8.50, -1.12]) and math (-2.95 [-5.51, -0.38]) scores. These differences were not mediated by Apgar score.

Conclusions

Multiple-birth SGA subgroups (vs. singleton SGA) or singleton SGA subgroup with co-occurrence of smoking and inadequate GWG (vs. singleton SGA subgroup without maternal smoking and inadequate gestational weight gain) have poorer cognitive development up to 5 y.

Adolescent Choline Supplementation Attenuates Working Memory Deficits in Rats Exposed to Alcohol During the Third Trimester Equivalent

BACKGROUND

Children exposed to alcohol prenatally may suffer from behavioral and cognitive alterations that adversely affect their quality of life. Animal studies have shown that perinatal supplementation with the nutrient choline can attenuate ethanol's adverse effects on development; however, it is not clear how late in development choline can be administered and still effectively reduce the consequences of prenatal alcohol exposure. Using a rodent model, this study examined whether choline supplementation is effective in mitigating alcohol's teratogenic effects when administered during adolescence/young adulthood.

METHODS

Sprague-Dawley rats were exposed to alcohol (5.25 g/kg/d) during the third trimester equivalent brain growth spurt, which occurs from postnatal day (PD) 4 to 9, via oral intubation. Sham-intubated and nontreated controls were included. Subjects were treated with 100 mg/kg/d choline chloride or vehicle from PD 40 to 60, a period equivalent to young adulthood in the rat. After the choline treatment had ceased, subjects were tested on a series of behavioral tasks: open field activity (PD 61 to 64), Morris water maze spatial learning (PD 65 to 73), and spatial working memory (PD 87 to 91).

RESULTS

Ethanol-exposed subjects were overactive in the activity chambers and impaired on both the spatial and the working memory versions of the Morris water maze. Choline treatment failed to attenuate alcohol-related overactivity in the open field and deficits in Morris water maze performance. In contrast, choline supplementation significantly mitigated alcohol-related deficits in working memory, which may suggest that choline administration at this later developmental time affects functioning of the prefrontal cortex.

CONCLUSIONS

The results indicate that adolescent choline supplementation can attenuate some, but not all, of the behavioral deficits associated with early developmental alcohol exposure. The results of this study indicate that dietary intervention may reduce some fetal alcohol effects, even when administered later in life, findings with important implications for adolescents and young adults with fetal alcohol spectrum disorders.

The impact of micronutrient supplementation in alcohol-exposed pregnancies on information processing skills in Ukrainian infants

The potential of micronutrients to ameliorate the impact of prenatal alcohol exposure (PAE) was explored in a clinical trial conducted in Ukraine. Cardiac orienting responses (ORs) during a habituation/dishabituation learning paradigm were obtained from 6 to 12 month-olds to assess neurophysiological encoding and memory. Women who differed in prenatal alcohol use were recruited during pregnancy and assigned to a group (No study-provided supplements, multivitamin/mineral supplement, or multivitamin/mineral supplement plus choline supplement). Heart rate was collected for 30 s prior to stimulus onset and 12 s post-stimulus onset. Difference values (∆HR) for the first 3 trials of each condition were aggregated for analysis. Gestational blood samples were collected to assess maternal nutritional status and changes as a function of the intervention. Choline supplementation resulted in a greater ∆HR on the visual habituation trials for all infants and for the infants with no PAE on the dishabituation trials. The latency of the response was reduced in both conditions for all infants whose mothers received choline supplementation. Change in gestational choline level was positively related to ∆HR during habituation trials and levels of one choline metabolite, dimethylglycine (DMG), predicted ∆HR during habituation trials and latency of responses. A trend was found between DMG and ∆HR on the dishabituation trials and latency of the response. Supplementation did not affect ORs to auditory stimuli. Choline supplementation when administered together with routinely recommended multivitamin/mineral prenatal supplements during pregnancy may provide a beneficial impact to basic learning mechanisms involved in encoding and memory of environmental events in alcohol-exposed pregnancies as well as non- or low alcohol-exposed pregnancies. Changes in maternal nutrient status suggested that one mechanism by which choline supplementation may positively impact brain development is through prevention of fetal alcohol-related depletion of DMG, a metabolic nutrient that can protect against overproduction of glycine, during critical periods of neurogenesis.

Maternal socio-economic status based on occupation and autism spectrum disorders: a national case-control study

BACKGROUND

The association between parental socio-economic status (SES) and autism spectrum disorders (ASD) has been studied in several countries, but the results have been contradictory.

AIMS

The aim of this study was to examine the association between maternal SES and subtypes of ASD in Finland.

METHODS

A national case-control study was conducted. Children born in 1991-2005 and diagnosed with ASD by the year 2007 were identified from the Finnish Hospital Discharge Register (FHDR). Their matched controls were selected from the Finnish Medical Birth Register (FMBR). There were 3468 cases and 13,868 controls. The information on maternal SES was collected from the FMBR and categorized into upper white-collar workers (referent), lower white-collar workers, blue-collar workers and "others", consisting of students, housewives and other groups with unknown SES. The statistical test used was conditional logistic regression.

RESULTS

The likelihood of ASD was increased among offspring of mothers who belong to the group "others" (adjusted OR = 1.2, 95% CI 1.009-1.3). The likelihood of Asperger's syndrome was decreased among offspring of lower white-collar workers (adjusted OR = 0.8, 95% CI 0.6-0.9) and blue-collar workers (adjusted OR = 0.6, 95% CI 0.5-0.7). The likelihood of pervasive developmental disorder not otherwise specified (PDD-NOS) was increased among offspring of blue-collar workers (adjusted OR = 1.5, 1.2-1.9) and "others" (adjusted OR = 1.3, 1.1-1.7). No association was found between maternal SES and childhood autism.

CONCLUSIONS

The association between maternal SES and ASD differs by ASD subtype. Socio-economic groups might differ from each other by risk factors for ASD subtypes or by their service use.

Neurologic complications of pediatric human immunodeficiency virus: implications for clinical practice and management challenges in the African setting

Approximately 3.4 million children worldwide are affected with human immunodeficiency virus (HIV)/AIDS with more than 90% of them residing in sub-Saharan Africa, according to the World Health Organization. A significant proportion of the children eligible for treatment with antiretroviral therapy are not currently receiving it. Neurologic manifestations of HIV are common in both adults and children. There is a large spectrum of neurologic conditions that may be caused by the virus; however, early invasion of the central nervous system by the virus, affecting the developing fetal and infant brain, is believed to result in the most common primary HIV-related central nervous system complication, HIV encephalopathy. This article summarizes the spectrum of neuro-HIV in children, focuses on the neurocognitive and behavioral sequelae, reviews the effects of treatment on the primary neurologic effects of the disease, and discusses the specific challenges of identifying and managing these problems in resource-limited contexts, such as those found on the African continent.

Diagnostic nomenclature for foetal alcohol spectrum disorders: the continuing challenge of causality

Prenatal alcohol exposure is a risk factor for neurologically based cognitive and adaptive disability. Diagnostic nomenclature for prenatally exposed children with cognitive and adaptive disability who lack features for foetal alcohol syndrome (FAS) or partial FAS includes the terms alcohol-related neurodevelopmental disorder (ARND) and foetal alcohol spectrum disorder(s) (FASD). Although these terms are now widely used, this paper argues that both are problematic. ARND is flawed by unjustifiably turning a risk factor into a causal factor and shrouding the result in terminological ambiguity, while FASD is not appropriate as a clinical label, and its use as a proxy for ARND deflects critical attention from the causal inferencing that is integral to diagnosing children with an alcohol-related teratogenic condition. Existing nomenclature is at odds with logical and evidence-based diagnosing and also has implications for interpretation of epidemiological data. Diagnostic nomenclature that is not tightly linked to causal inference is preferable at the present stage of this field's development.

Fetal central nervous system development and alcohol--the evidence so far

Currently in the UK, there is no absolute guidance about alcohol consumption in pregnancy. The guidance for drinking during pregnancy is one or two units of alcohol one or two times weekly, but conservative advice is to abstain as a cautionary measure. Despite the lack of consensus about the safe levels of alcohol consumption in pregnancy, there is increasing evidence of the impact of alcohol on the developing central nervous system. This article explores the evidence regarding alcohol consumption and its effects on the developing fetal central nervous system.

Gestational restraint stress and the developing dopaminergic system: an overview

Prenatal stress exerts a strong impact on fetal brain development in rats impairing adaptation to stressful conditions, subsequent vulnerability to anxiety, altered sexual function, and enhanced propensity to self-administer drugs. Most of these alterations have been attributed to changes in the neurotransmitter dopamine (DA). In humans; dysfunction of dopaminergic system is associated with development of several neurological disorders, such as Parkinson disease, schizophrenia, attention-deficit hyperactivity disorder, and depression. Evidences provided by animal research, as well as retrospective studies in humans, pointed out that exposure to adverse events in early life can alter adult behaviors and neurochemical indicators of midbrain DA activity, suggesting that the development of the DA system is sensitive to disruption by exposure to early stressors. The purpose of this article is to provide a general overview of published studies and our own study related to the effect of prenatal insults on the development of DA metabolism and biology, focusing mainly in articles involving prenatal-restraint stress protocols in rats. We will also attempt to make a correlation between theses alterations and DA-related pathological processes in humans.

KCTD8 gene and brain growth in adverse intrauterine environment: a genome-wide association study

The most dramatic growth of the human brain occurs in utero and during the first 2 years of postnatal life. Genesis of the cerebral cortex involves cell proliferation, migration, and apoptosis, all of which may be influenced by prenatal environment. Here, we show that variation in KCTD8 (potassium channel tetramerization domain 8) is associated with brain size in female adolescents (rs716890, P = 5.40 × 10(-09)). Furthermore, we found that the KCTD8 locus interacts with prenatal exposure to maternal cigarette smoking vis-à-vis cortical area and cortical folding: In exposed girls only, the KCTD8 locus explains up to 21% of variance. Using head circumference as a proxy of brain size at 7 years of age, we have replicated this gene-environment interaction in an independent sample. We speculate that KCTD8 might modulate adverse effects of smoking during pregnancy on brain development via apoptosis triggered by low intracellular levels of potassium, possibly reducing the number of progenitor cells.

New estimates of the number of children living with substance misusing parents: results from UK national household surveys

BACKGROUND

The existing estimates of there being 250,000 - 350,000 children of problem drug users in the UK (ACMD, 2003) and 780,000 - 1.3 million children of adults with an alcohol problem (AHRSE, 2004) are extrapolations of treatment data alone or estimates from other countries, hence updated, local and broader estimates are needed.

METHODS

The current work identifies profiles where the risk of harm to children could be increased by patterns of parental substance use and generates new estimates following secondary analysis of five UK national household surveys.

RESULTS

The Health Survey for England (HSfE) and General Household Survey (GHS) (both 2004) generated consistent estimates - around 30% of children under-16 years (3.3 - 3.5 million) in the UK lived with at least one binge drinking parent, 8% with at least two binge drinkers and 4% with a lone (binge drinking) parent. The National Psychiatric Morbidity Survey (NPMS) indicated that in 2000, 22% (2.6 million) lived with a hazardous drinker and 6% (705,000) with a dependent drinker. The British Crime Survey (2004) and NPMS (2000) indicated that 8% (up to 978,000) of children lived with an adult who had used illicit drugs within that year, 2% (up to 256,000) with a class A drug user and 7% (up to 873,000) with a class C drug user. Around 335,000 children lived with a drug dependent user, 72,000 with an injecting drug user, 72,000 with a drug user in treatment and 108,000 with an adult who had overdosed. Elevated or cumulative risk of harm may have existed for the 3.6% (around 430,000) children in the UK who lived with a problem drinker who also used drugs and 4% (half a million) where problem drinking co-existed with mental health problems. Stronger indicators of harm emerged from the Scottish Crime Survey (2000), according to which 1% of children (around 12,000 children) had witnessed force being used against an adult in the household by their partner whilst drinking alcohol and 0.6% (almost 6000 children) whilst using drugs.

CONCLUSION

Whilst harm from parental substance use is not inevitable, the number of children living with substance misusing parents exceeds earlier estimates. Widespread patterns of binge drinking and recreational drug use may expose children to sub-optimal care and substance-using role models. Implications for policy, practice and research are discussed.

Altered water diffusivity in cortical association tracts in children with early deprivation identified with Tract-Based Spatial Statistics (TBSS)

Institutional rearing is associated with neurocognitive and behavioral difficulties. Although such difficulties are thought to reflect abnormal neurologic development resulting from early social deprivation (ED) and there is evidence for functional abnormality in children with histories of ED, the impact of early deprivation on brain anatomy has received little study in humans. The present study utilized an objective and sensitive neuroimaging analysis technique (Tract-Based Spatial Statistics) to evaluate white matter fractional anisotropy (FA) and diffusivity in a group of right-handed children with histories of ED (n = 17; mean age = 10.9 + 2.6 years) as compared with age-matched healthy controls (n = 15; mean age = 11.7 + or - 2.8 years). Participants underwent magnetic resonance imaging diffusion tensor imaging sequences and comprehensive neuropsychological evaluations. Results revealed reduced FA in frontal, temporal, and parietal white matter including components of uncinate and superior longitudinal fasciculi, in children with histories of ED, providing further support for limbic and paralimbic abnormalities in children with such histories. Furthermore, white matter abnormalities were associated with duration of time in the orphanage and with inattention and hyperactivity scores. It is suspected that the observed white matter abnormalities are associated with multiple depriving factors (e.g., poor prenatal care, postnatal stress) associated with institutional caregiving.

Neuroimaging of children following prenatal drug exposure

Recent advances in MR-based brain imaging methods have provided unprecedented capabilities to visualize the brain. Application of these methods has allowed identification of brain structures and patterns of functional activation altered in offspring of mothers who used licit (e.g., alcohol and tobacco) and illicit (e.g., cocaine, methamphetamine, and marijuana) drugs during pregnancy. Here we review that literature, which though somewhat limited by the complexities of separating the specific effects of each drug from other confounding variables, points to sets of interconnected brain structures as being altered following prenatal exposure to drugs of abuse. In particular, dopamine-rich cortical (e.g., frontal cortex) and subcortical (e.g., basal ganglia) fetal brain structures show evidence of vulnerability to intrauterine drug exposure suggesting that during brain development drugs of abuse share a specific profile of developmental neurotoxicity. Such brain malformations may shed light on mechanisms underlying prenatal drug-induced brain injury, may serve as bio-markers of significant intrauterine drug exposure, and may additionally be predictors of subsequent neuro-developmental compromise. Wider clinical use of these research-based non-invasive methods will allow for improved diagnosis and allocation of therapeutic resources for affected infants, children, and young adults.

Maturation-dependent alcohol resistance in the developing mouse: cerebellar neuronal loss and gene expression during alcohol-vulnerable and -resistant periods

BACKGROUND

Alcohol abuse during pregnancy injures the fetal brain. One of alcohol's most important neuroteratogenic effects is neuronal loss. Rat models have shown that the cerebellum becomes less vulnerable to alcohol-induced neuronal death as it matures. We determined if maturation-dependent alcohol resistance occurs in mice and compared patterns of gene expression during the alcohol resistant and sensitive periods.

METHODS

Neonatal mice received alcohol daily over postnatal day (PD) 2 to 4 or PD8 to 10. Purkinje cells and granule cells were quantified on PD25. The temporal expression patterns of 4 neuro-developmental genes and 3 neuro-protective genes in the cerebellum were determined daily over PD0 to 15 to determine how gene expression changes as the cerebellum transitions from alcohol-vulnerable to alcohol-resistant. The effect of alcohol on expression of these genes was determined when the cerebellum is alcohol sensitive (PD4) and resistant (PD10).

RESULTS

Purkinje and granule cells were vulnerable to alcohol-induced death at PD2 to 4, but not at PD8 to 10. Acquisition of maturation-dependent alcohol resistance coincided with changes in the expression of neurodevelopmental genes. The vulnerability of cerebellar neurons to alcohol toxicity declined in parallel with decreasing levels of Math1 and Cyclin D2, markers of immature granule cells. Likewise, the rising resistance to alcohol toxicity paralleled increasing levels of GABA alpha-6 and Wnt-7a, markers of mature granule neurons. Expression of growth factors and genes with survival promoting function (IGF-1, BDNF, and cyclic AMP response element binding protein) did not rise as the cerebellum transitioned from alcohol-vulnerable to alcohol-resistant. All 3 were expressed at substantial levels during the vulnerable period and were not expressed at higher levels later. Acute alcohol exposure altered the expression of neurodevelopmental genes and growth factor genes when administered either during the alcohol vulnerable period or resistant period. However, the patterns in which gene expression changed varied among the genes and depended on timing of alcohol administration.

CONCLUSIONS

Mice have a temporal window of vulnerability in the first week of life, during which cerebellar neurons are more sensitive to alcohol toxicity than during the second week. Expression of genes governing neuronal maturation changes in synchrony with the acquisition of alcohol resistance. Growth factors do not rise as the cerebellum transitions from alcohol-vulnerable to alcohol-resistant. Thus, a process intrinsic to neuronal maturation, rather than rising levels of growth factors, likely underlies maturation-dependent alcohol resistance.

Metabonomic and metallomic profiling in the amniotic fluid of malnourished pregnant rats

Epidemiology and studies in animal models have revealed that prenatal malnutrition is highly correlated with abnormal fetal neurodevelopment. We present here a combined metabonomic and metallomic profiling technique to associate the metabolic and trace-elemental composition variations of rat amniotic fluid (AF) in malnourished pregnant rats with the retardation of fetal rat neurodevelopment. The AF samples from three groups of pregnant Sprague-Dawley rats, which were fed either a normal diet, a low-protein diet, or "a famine diet", were subjected to GC/MS and ICP/MS combined with multivariate data analysis (MVDA). PCA scores plot of both GC/MS and ICP/MS data showed similar and unique metabolic signatures of AF in response to the different diets. Rats in the famine group released increased amounts of glycine, inositol, putrescine, and rubidium and decreased amounts of methionine, dopa, tryptophan, glutamine, zinc, cobalt, and selenium in the AF. These discriminable variations in the AF may indicate the abnormality of a number of metabolic pathways in fetal rats including the folate cycle and methionine pathway, the monoamine pathway, and tri-iodothyronine (T3) metabolism. The abnormalities may be the result of metabolites or elemental differences or a combination of both. This study demonstrates the potential of combining profiling of small-molecule metabolites and trace elements to broaden the understanding of biological variations associated with fetal neurodevelopment induced by environmental perturbation.