Smaller subcortical volumes and cognitive deficits in children with prenatal methamphetamine exposure

Pathologies in a preterm infant exposed to methamphetamine in utero: Case report and literature review

Methamphetamine (M-AMP) use among women of childbearing age is a growing global concern Herein we present an unusual clinical presentation in a preterm infant born to a mother who used M-AMP during pregnancy. A 26-year-old woman, with no prenatal care, presented to the emergency department with aggressive behavior and visible skin wounds led to suspicion of substance abuse. Urine analysis confirmed high levels of amphetamines (2000 ng/mL). The infant was delivered by cesarean section at 30 + 5/7 weeks, with a birth weight of 1580 grams. The infant, admitted to the NICU due to respiratory distress and prematurity, initially required nasal CPAP and exhibited transient tachypnea. Enteral feeding was initiated at 24 hours of life but was halted due to feeding intolerance. Once the baby's symptoms subsided, enteral feeding was gradually reintroduced and slowly increased. The infant successfully transitioned to full enteral feeding by the 15th postnatal day. Cranial ultrasound revealed hyperechoic areas in the right parietal lobe, and subsequent MRI showed millimetric T1 hyperintense areas, indicative of parenchymal microischemia. Preterm infants exposed to methamphetamine in utero may not show typical withdrawal symptoms. Diagnostic challenges arise from prematurity, with significant impacts on brain development and potential neurocognitive deficits.

Amphetamine exposure during embryogenesis changes expression and function of the dopamine transporter in Caenorhabditis elegans offspring

The dopamine transporter (DAT) is a transmembrane protein that regulates dopamine (DA) neurotransmission by binding to and moving DA from the synaptic cleft back into the neurons. Besides moving DA and other endogenous monoamines, DAT is also a neuronal carrier for exogenous compounds such as the psychostimulant amphetamine (Amph), and several studies have shown that Amph-induced behaviors require a functional DAT. Here, we demonstrate that exposure to Amph during early development causes behavioral, functional, and epigenetic modifications at the Caenorhabditis elegans DAT gene homolog, dat-1, in C. elegans offspring. Specifically, we show that, while embryos exposed to Amph generate adults that produce offspring with no obvious behavioral alterations, both adults and offspring exhibit an increased behavioral response when challenged with Amph. Our functional studies suggest that a decrease in DAT-1 expression underlies the increased behavioral response to Amph seen in offspring. Moreover, our epigenetic data suggest that histone methylation is a mechanism utilized by Amph to maintain changes in DAT-1 expression in offspring. Taken together, our data reveal that Amph, by altering the epigenetic landscape of DAT, propagates long-lasting functional and behavioral changes in offspring.

Trans-generational effects of parental exposure to drugs of abuse on offspring memory functions

Recent evidence reported that parental-derived phenotypes can be passed on to the next generations. Within the inheritance of epigenetic characteristics allowing the transmission of information related to the ancestral environment to the offspring, the specific case of the trans-generational effects of parental drug addiction has been extensively studied. Drug addiction is a chronic disorder resulting from complex interactions among environmental, genetic, and drug-related factors. Repeated exposures to drugs induce epigenetic changes in the reward circuitry that in turn mediate enduring changes in brain function. Addictive drugs can exert their effects trans-generally and influence the offspring of addicted parents. Although there is growing evidence that shows a wide range of behavioral, physiological, and molecular phenotypes in inter-, multi-, and trans-generational studies, transmitted phenotypes often vary widely even within similar protocols. Given the breadth of literature findings, in the present review, we restricted our investigation to learning and memory performances, as examples of the offspring's complex behavioral outcomes following parental exposure to drugs of abuse, including morphine, cocaine, cannabinoids, nicotine, heroin, and alcohol.

Methamphetamine exposure drives cell cycle exit and aberrant differentiation in rat hippocampal-derived neurospheres

Introduction: Methamphetamine (METH) abuse by pregnant drug addicts causes toxic effects on fetal neurodevelopment; however, the mechanism underlying such effect of METH is poorly understood. Methods: In the present study, we applied three-dimensional (3D) neurospheres derived from the embryonic rat hippocampal tissue to investigate the effect of METH on neurodevelopment. Through the combination of whole genome transcriptional analyses, the involved cell signalings were identified and investigated. Results: We found that METH treatment for 24 h significantly and concentration-dependently reduced the size of neurospheres. Analyses of genome-wide transcriptomic profiles found that those down-regulated differentially expressed genes (DEGs) upon METH exposure were remarkably enriched in the cell cycle progression. By measuring the cell cycle and the expression of cell cycle-related checkpoint proteins, we found that METH exposure significantly elevated the percentage of G0/G1 phase and decreased the levels of the proteins involved in the G1/S transition, indicating G0/G1 cell cycle arrest. Furthermore, during the early neurodevelopment stage of neurospheres, METH caused aberrant cell differentiation both in the neurons and astrocytes, and attenuated migration ability of neurospheres accompanied by increased oxidative stress and apoptosis. Conclusion: Our findings reveal that METH induces an aberrant cell cycle arrest and neuronal differentiation, impairing the coordination of migration and differentiation of neurospheres.

Maternal use of methamphetamine alters cardiovascular function in the adult offspring

Methamphetamine is one of the most commonly used illicit drugs during pregnancy. Most studies investigating the impact of maternal use of methamphetamine on children have focused on neurological outcomes. In contrast, cardiovascular outcomes in these children have not been characterized. Recent studies in rodents provide evidence that prenatal exposure to methamphetamine induces changes in cardiac gene expression, changes in the heart's susceptibility to ischemic injury, and changes in vascular function that may increase the risk of developing cardiovascular disorders later in life. Importantly, these changes are sex-dependent. This review summarizes our current understanding of how methamphetamine use during pregnancy impacts the cardiovascular function of adult offspring and highlights gaps in our knowledge of the potential cardiovascular risks associated with prenatal exposure to methamphetamine.

Shaping the risk for late-life neurodegenerative disease: A systematic review on prenatal risk factors for Alzheimer's disease-related volumetric brain biomarkers

Environmental exposures including toxins and nutrition may hamper the developing brain in utero, limiting the brain's reserve capacity and increasing the risk for Alzheimer's disease (AD). The purpose of this systematic review is to summarize all currently available evidence for the association between prenatal exposures and AD-related volumetric brain biomarkers. We systematically searched MEDLINE and Embase for studies in humans reporting on associations between prenatal exposure(s) and AD-related volumetric brain biomarkers, including whole brain volume (WBV), hippocampal volume (HV) and/or temporal lobe volume (TLV) measured with structural magnetic resonance imaging (PROSPERO; CRD42020169317). Risk of bias was assessed using the Newcastle Ottawa Scale. We identified 79 eligible studies (search date: August 30th, 2020; Ntotal=24,784; median age 10.7 years) reporting on WBV (N = 38), HV (N = 63) and/or TLV (N = 5) in exposure categories alcohol (N = 30), smoking (N = 7), illicit drugs (N = 14), mental health problems (N = 7), diet (N = 8), disease, treatment and physiology (N = 10), infections (N = 6) and environmental exposures (N = 3). Overall risk of bias was low. Prenatal exposure to alcohol, opioids, cocaine, nutrient shortage, placental dysfunction and maternal anemia was associated with smaller brain volumes. We conclude that the prenatal environment is important in shaping the risk for late-life neurodegenerative disease.

Maternal use of methamphetamine induces sex-dependent changes in myocardial gene expression in adult offspring

Methamphetamine is a commonly abused illicit stimulant that has prevalent use among women of child-bearing age. While there are extensive studies on the neurological effects of prenatal methamphetamine exposure, relatively little is known about the effect of prenatal methamphetamine on the adult cardiovascular system. Earlier work demonstrated that prenatal methamphetamine exposure sex dependently (females only) sensitizes the adult heart to ischemic injury. These data suggest that prenatal exposure to methamphetamine may induce sex-dependent changes in cardiac gene expression that persist in adult offspring. The goal of this study was to test the hypothesis that prenatal methamphetamine exposure induces changes in cardiac gene expression that persist in the adult heart. Hearts of prenatally exposed female offspring exhibited a greater number of changes in gene expression compared to male offspring (184 changes compared with 74 in male offspring and 89 changes common between both sexes). Dimethylarginine dimethylaminohydrolase 2 and 3-hydroxybutyrate dehydrogenase 1 (genes implicated in heart failure) were shown by Western Blot to be under expressed in adult females that were prenatally exposed to methamphetamine, while males were deficient in 3-Hydroxybutyrate Dehydrogenase 1 only. These data indicate that prenatal methamphetamine exposure induces changes in gene expression that persist into adulthood. This is consistent with previous findings that prenatal methamphetamine sex dependently sensitizes the adult heart to ischemic injury and may increase the risk of developing cardiac disorders during adulthood.

Effects of prenatal methamphetamine exposure on spatial cognition and hippocampal synaptic plasticity in adolescent rats

Global rise in methamphetamine (MA) abuse during pregnancy has placed a large number of children at risk for the adverse consequences of prenatal methamphetamine exposure (PME). While behavioral and neurocognitive deficits of PME have been extensively studied in humans and adult rodents, far less is known regarding the sex- and dose-dependent effects of PME as well as the underlying mechanisms. Adolescence in nonhuman primates is also a less explored territory. In the present study, PME was inducted by oral treatment to pregnant rats on gestational days 15-19 with either low dose (0.1 mg/ml) or high dose (0.6 mg/ml) of MA. The cognitive effects of PME were then evaluated in two adolescence age-intervals: early adolescent (started on postnatal day [PND] 21) and mid-adolescent (started on PND 33), among male and female rat offspring using Morris water maze (MWM) test. Alterations in hippocampal synaptic plasticity in Schaffer collaterals-CA1 pathway were also measured in vitro. Results of behavioral test showed that PME led to serious deficits of learning and memory abilities in both male and female rat offspring. PME also depressed LTP in most of the PME subgroups. Moreover, 21-day-old rats were more sensitive to PME-induced cognitive impairment in MWM tasks, but not in hippocampal synaptic plasticity, than 33-day-old rats. No sex-dependent effects of PME were found on the cognitive function and synaptic plasticity. These findings confirmed that PME impacted negatively on cognitive performance in prepubertal male and female rats, and the impairment of hippocampal synaptic functions might partly play a significant role in these effects.

Methamphetamine use during the first or second half of pregnancy worsens cardiac ischemic injury in adult female offspring

There is growing evidence that methamphetamine use during pregnancy may produce detrimental cardiovascular effects in the adult offspring. Prior work demonstrated that chronic methamphetamine exposure throughout the gestational period causes adult female offspring to become hypersensitive to myocardial ischemic injury. The goal of the present study was to determine whether this methamphetamine-induced effect occurs early or late in the gestational period. Pregnant female rats were divided into 4 experimental groups. Groups 1 and 2 received subcutaneous injections of saline (group 1) or methamphetamine (5 mg/kg) (group 2) throughout the gestational period. Group 3 received methamphetamine injections on days 1-11 and saline on days 12-22, and group 4 received saline on days 1-11 and methamphetamine on days 12-22. Hearts were isolated from adult (8 weeks) female offspring and subjected to 30 min ischemia and 2 hours reperfusion on a Langendorff isolated heart apparatus. Contractile function was measured via an intraventricular balloon, and infarct size was measured by triphenyltetrazolium chloride staining. Infarcts were significantly larger in methamphetamine exposed offspring regardless of whether they had been exposed to methamphetamine during the first half or the second half of the gestational period. Prenatal exposure to methamphetamine had no effect on preischemic contractile function or postischemic recovery of contractile function. These data indicate that methamphetamine use during either the first half or second half of pregnancy increases susceptibility to myocardial infarction in adult female offspring. These data provide further evidence that prenatal exposure to methamphetamine may increase the risk of developing cardiovascular diseases during adulthood.

An intergenerational lifespan perspective on the neuroscience of prenatal substance exposure

Prenatal substance exposure has the potential to impact a variety of domains, with neurobiological effects that last throughout the lifespan. Different substances may impact the brain in both specific and diffuse ways; however, the aberrant neural outcomes following exposure tend to coalesce in three areas: (1) sensorimotor development; (2) arousal, motivation, and reward; and (3) executive functioning, impulse control, and emotion regulation. This manuscript represents a summary and update of a previous review (Morie et al., 2019). We organize this piece by domain and summarize data from published neuroimaging studies that examine the neural correlates of prenatal exposure across developmental stages. While the published neuroimaging literature in the area of prenatal exposure has a range of sampling concerns that may limit generalizability as well as longitudinal prediction, the findings to date do point to domains of interest warranting further study. With this caveat, we synthesize the extant findings to describe ways in which prenatal substance exposure is associated with developmental psychopathology and implicated in potentially aberrant behavioral patterns beginning in infancy and persisting through childhood, adolescence, adulthood, and even parenthood. We also examine how substance abuse may impact parenting behaviors that in turn influences infant and child behavior in ways that may be additive or obscure the direct teratological effects of prenatal exposure. Given this observation, we offer an additional intergenerational lens through which prenatal substance exposure should be studied.

Methamphetamine exposure during pregnancy: A meta-analysis of child developmental outcomes

This paper examines developmental outcomes for children prenatally exposed to methamphetamine through maternal use. PSYCHINFO, Scopus, PubMed and ERIC databases were systematically searched for studies up to December 2020. The search identified 38 articles examining cognitive, language, motor and neuroanatomical outcomes in children from birth to 16 years. Study quality was appraised using the Newcastle Ottawa Quality Assessment Scale. Findings from neuroanatomical studies suggested that prenatal methamphetamine exposure may alter whole brain microstructure and reduce subcortical volumes across multiple brain regions. Meta-analysis of 14 studies using a random-effects model revealed associations between exposure and poorer intellectual functioning (Cohen's d = 0.89, 95 % CI: 0.47-1.30), problem solving skills (Cohen's d = 0.82, 95 % CI: 0.07 -1.56), short-term memory (Cohen's d = 0.91, 95 % CI: 0.38-1.43), and language development (Cohen's d = 0.74, 95 % CI: 0.30-1.18). These results emphasise the significant impact of intrauterine methamphetamine exposure across multiple areas of child development, noting that limited total sample size, heterogeneity between studies and control for confounds suggested further studies are required. There is a need for further intervention studies to identify effective prevention and harm minimisation approaches.

Methamphetamine: burden, mechanism and impact on pregnancy, the fetus, and newborn

While the opioid epidemic has garnered worldwide attention, increasing methamphetamine use has drawn less scrutiny. Methamphetamine is a highly addictive psychostimulant affecting people from all backgrounds and regions. It is a potent vasoconstrictor, is associated with arrhythmias and dilated cardiomyopathy. Cardiovascular disease-related mortality is a leading cause of death in methamphetamine users. Women of childbearing age increasingly use methamphetamine and continue during pregnancy. In the short term, prenatal methamphetamine use is associated with fetal growth restriction and low birth weight in the newborn. Animal studies show reduction in uterine and umbilical blood flow following maternal methamphetamine administration. Based on currently available evidence, prenatal methamphetamine exposure has transient effects on gross motor development, no effect on language and cognition, and modest effects on behavior and executive functioning with poor inhibitory control, which may be attributable to early adversity. Further research is needed to evaluate long-term effects of prenatal methamphetamine exposure.

Prenatal Exposure to Methamphetamine Causes Vascular Dysfunction in Adult Male Rat Offspring

Methamphetamine use during pregnancy can have negative consequences on the offspring. However, most studies investigating the impact of prenatal exposure to methamphetamine have focused on behavioral and neurological outcomes. Relatively little is known regarding the impact of prenatal methamphetamine on the adult cardiovascular system. This study investigated the impact of chronic fetal exposure to methamphetamine on vascular function in adult offspring. Pregnant female rats received daily saline or methamphetamine (5 mg/kg) injections starting on gestational day 1 and continuing until the pups were born. Vascular function was assessed in 5 month old offspring. Prenatal methamphetamine significantly decreased both the efficacy and potency of acetylcholine-induced relaxation in isolated male (but not female) aortas when perivascular adipose tissue (PVAT) remained intact. However, prenatal methamphetamine had no impact on acetylcholine-induced relaxation when PVAT was removed. Nitroprusside-induced relaxation of the aorta was unaffected by prenatal methamphetamine. Angiotensin II-induced contractile responses were significantly potentiated in male (but not female) aortas regardless of the presence of PVAT. This effect was reversed by L-nitro arginine methyl ester (L-NAME). Serotonin- and phenylephrine-induced contraction were unaffected by prenatal methamphetamine. Prenatal methamphetamine had no impact on acetylcholine-induced relaxation of third order mesenteric arteries and no effect on basal blood pressure. These data provide evidence that prenatal exposure to methamphetamine sex-dependently alters vasomotor function in the vasculature and may increase the risk of developing vascular disorders later in adult life.

Psychotropic drug abuse in pregnancy and its impact on child neurodevelopment: A review

Substance abuse by women of child-bearing age and fetal in utero drug exposure has increased in the number of infants born with health issues. Prenatal exposure to psychoactive substances can lead to neurological and neurodevelopmental deficits later in life. Useful data concerning the effects of psychoactive drugs on fetal neurodevelopmental status are sparse. Understanding the neurodevelopmental consequences of prenatally drug-exposed children has become a pressing global concern. The aim of this review is to gather current evidence and information on neurodevelopmental outcomes of in utero drug exposure. A literature search was performed on the PubMed, Scopus, and Google Scholar databases using the terms "psychotropic drugs", "neurodevelopmental consequences", "prenatal drug exposure", and "pregnancy". Available studies on in utero drug exposure were reviewed and found to support the idea that some degree of health issues are present in fetuses and children. Different psychoactive substances have profound neurodevelopmental consequences, such as structural brain changes, poor attention span, Down syndrome, attention deficit hyperactivity disorder, autism spectrum disorder, imbalances in neurotransmitter levels, and many structural deficits. The pervasive use of psychoactive drugs in women of child-bearing age is an important health concern. Further scientific efforts are needed to investigate the effect of prenatal exposure to psychoactive drugs on children.

Prenatal methamphetamine-impact on the mother and child-a review

Methamphetamine (MA) is the second most commonly used illicit drug in the world, after cannabis. There are limited data on the outcomes of pregnant MA users but there is rapidly emerging evidence to suggest that they are more vulnerable, marginalized and impoverished compared with other drug-using mothers. MA use during pregnancy is associated with worse pregnancy outcomes and significantly higher rates of co-existing health and psychosocial problems. Newborn infants exposed to MA are at increased risk of perinatal complications, present differently at birth to infants exposed to other drugs of dependency such as opioids and have poorer neurological adaptation and feeding difficulties. Sparse literature from neuroimaging and cohort studies suggests that the neurocognitive deficits in MA exposed children persist, even into adulthood. Current clinical practice guidelines for the care of substance exposed pregnant women are opioid-centric with little attention paid to the consequences of prenatal MA exposure.

Can prenatal methamphetamine exposure be considered a good animal model for ADHD?

Attention-deficit/hyperactivity disorder (ADHD) is a mental disorder with a heterogeneous origin with a global incidence that continues to grow. Its causes and pathophysiological mechanisms are not fully understood. It includes a combination of persistent symptoms such as difficulty in concentration, hyperactivity and impulsive behavior. Maternal methamphetamine (MA) abuse is a serious problem worldwide, it can lead to behavioral changes in their offspring that have similarities with behavioral changes seen in children with ADHD. There are several types of ADHD animal models, e.g. genetic models, pharmacologically, chemically and exogenously induced models. One of the exogenously induced ADHD models is the hypoxia-induced model. Our studies, as well as those of others, have demonstrated that maternal MA exposure can lead to abnormalities in the placenta and umbilical cord that result in prenatal hypoxia as well as fetal malnutrition that can result in irreversible changes to experimental animals. Therefore, the aim the present study was to compare the cognitive impairments in MA exposure model with those in established model of ADHD - prenatal hypoxia model, to test whether MA exposure is a valid model of ADHD. Pregnant Wistar rats were divided into four groups based on their gestational exposure to MA: (1) daily subcutaneous injections of MA (5 mg/kg), (2) saline injections at the same time and volume, (3) daily 1-hr hypoxia (10 % O2), and (4) no gestational exposure (controls). Male rat offspring were tested for short-term memory in the Novel Object Recognition Test and the Object Location Test between postnatal days 35 and 40. Also their locomotor activity in both tests was measured. Based on the present results, it seems that prenatal MA exposure is not the best animal model for ADHD since it shows corresponding symptoms only in certain measures. Given our previous results supporting our hypothesis, more experiments are needed to further test possible use of prenatal MA exposure as an animal model of the ADHD.

Substance Use During Pregnancy: A Comparative Review of Major Guidelines

Importance

Substance use during pregnancy is a major health issue for both the mother and the fetus, but it also represents an important public health concern.

Objective

The aim of this review was to summarize and compare recommendations from recently published guidelines on substance use during pregnancy and especially regarding alcohol, smoking, and drug use.

Evidence Acquisition

A descriptive review of guidelines from the Royal Australian and New Zealand College of Obstetricians and Gynaecologists, the World Health Organization (WHO), the Society of Obstetricians and Gynaecologists of Canada, and the American College of Obstetricians and Gynecologists on substance use was conducted. Regarding the term "substance use," the most recently published Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition substances were used.

Results

All the reviewed guidelines recommend appropriate counseling and screening women regarding alcohol, smoking, and drug use during the antenatal period, while the management options vary. More specifically, the prompt management of alcohol dependence is emphasized by all the guidelines except from the Royal Australian and New Zealand College of Obstetricians and Gynaecologists, which makes no recommendation upon. The use of alcohol during breastfeeding should be avoided. Regarding smoking cessation, all guidelines recommend the use of certain psychosocial, behavioral interventions, and pharmacotherapy. All the guidelines, except the one from the WHO, suggest screening drug users for coexistent sexually transmitted infections. Brief interventions are considered beneficial, while a gradual decrease in benzodiazepines is suggested, as well as the discontinuation of marijuana and methamphetamine use. However, there is controversy regarding breastfeeding in those women as the WHO recommends in favor, whereas the Society of Obstetricians and Gynaecologists of Canada and the American College of Obstetricians and Gynecologists recommend against this practice. Finally, all the guidelines state that, following delivery, close monitoring of the neonate is needed.

Conclusions

The diversity of guidelines' recommendations concerning substance use reflects the different ways of the management of pregnant women during routine antenatal care due to absence of strong evidence. More research in the areas of dispute may allow the adoption of an international consensus, in order to early detect and appropriately manage pregnant women with harmful addictions.

Methamphetamine abuse disturbs the dopaminergic system to impair hippocampal-based learning and memory: An overview of animal and human investigations

Diverse intellectual functions including memory are some important aspects of cognition. Dopamine is a neurotransmitter of the catecholamine family, which contributes to the experience of pleasure and/or emotional states but also plays crucial roles in learning and memory. Methamphetamine is an illegal drug, the abuse of which leads to long lasting pathological manifestations in the brain. Chronic methamphetamine-induced neurotoxicity results in an alteration of various parts of the memory systems by affecting learning processes, an effect attributed to the structural similarities of this drug with dopamine. An evolving field of research established how cognitive deficits in abusers arise and how they could possibly trigger neurodegenerative disorders. Thus, the drugs-induced tenacious neurophysiological changes of the dopamine system trigger cognitive deficits, thereby affirming the influence of this addictive drug on learning, memory and executive function in human abusers. Here we present an overview of the effects of methamphetamine abuse on cognitive functions, dopaminergic transmission and hippocampal integrity as they have been validated in animals and in humans during the past 20 years.

Effects of Prenatal Methamphetamine Exposure on the Developing Human Brain: A Systematic Review of Neuroimaging Studies

Methamphetamine (MA) can cross the placenta in pregnant women and cause placental abruption and developmental alterations in offspring. Previous studies have found prenatal MA exposure effects on the social and cognitive performance of children. Recent studies reported some alterations in structural and functional magnetic resonance imaging (MRI) of prenatal MA-exposed offspring. In this study, we aimed to investigate the effect of prenatal MA exposure on brain development using recently published structural, metabolic, and functional MRI studies. According to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we searched PubMed and SCOPUS databases for articles that used each brain imaging modality in prenatal MA-exposed children. Seventeen studies were included in this study. We investigated brain imaging alterations using 17 articles with four different modalities, including structural MRI, diffusion tensor imaging (DTI), magnetic resonance spectroscopy (MRS), and functional MRI (fMRI). The participants’ age range was from infancy to 15 years. Our findings demonstrated that prenatal MA exposure is associated with macrostructural, microstructural, metabolic, and functional deficits in both cortical and subcortical areas. However, the most affected regions were the striatum, frontal lobe, thalamus and the limbic system, and white matter (WM) fibers connecting these regions. The findings from our study might have valuable implications for targeted treatment of neurocognitive and behavioral deficits in children with prenatal MA exposure. Even so, our results should be interpreted cautiously due to the heterogeneity of the included studies in terms of study populations and methods of analysis.

The Adverse Effects of Prenatal METH Exposure on the Offspring: A Review

Abuse of methamphetamine (METH), an illicit psychostimulant, is a growing public health issue. METH abuse during pregnancy is on the rise due to its stimulant, anorectic, and hallucinogenic properties. METH can lead to multiple organ toxicity in adults, including neurotoxicity, cardiovascular toxicity, and hepatotoxicity. It can also cross the placental barrier and have long-lasting effects on the fetus. This review summarizes neurotoxicity, cardiovascular toxicity, hepatotoxicity, toxicity in other organs, and biomonitoring of prenatal METH exposure, as well as the possible emergence of sensitization associated with METH. We proposed the importance of gut microbiota in studying prenatal METH exposure. There is rising evidence of the adverse effects of METH exposure during pregnancy, which are of significant concern.

A prospective longitudinal study shows putamen volume is associated with moderate amphetamine use and resultant cognitive impairments

Background

Amphetamine-type stimulants (ATS) have become a critical public health issue. Animal models have indicated a clear neurotoxic potential of ATSs. In humans, chronic use has been associated with cognitive deficits and structural brain abnormalities. However, cross-sectional retrospective designs in chronic users cannot truly determine the causal direction of the effects.

Objective

To prospectively determine effects of occasional ATS use on cognitive functioning and brain structure.

Methods

In a prospective longitudinal study design, cognitive functioning and brain structure were assessed at baseline and at 12-month follow-up in occasional ATS users (cumulative lifetime use <10 units at baseline).

Results

Examination of change scores between the initial examination and follow-up revealed declined verbal memory performance and putamen volume in users with high relative to low interim ATS exposure. In the entire sample, interim ATS use, memory decline, and putamen volume reductions were strongly associated.

Conclusions

The present findings support the hypothesis that ATS use is associated with deficient dorsal striatal morphology that might reflect alterations in dopaminergic pathways. More importantly, these findings strongly suggest that even occasional, low-dose ATS use disrupts striatal integrity and cognitive functioning.

Glial cell diversity and methamphetamine-induced neuroinflammation in human cerebral organoids

Methamphetamine (METH) is a potent stimulant that induces a euphoric state but also causes cognitive impairment, neurotoxicity and neurodevelopmental deficits. Yet, the molecular mechanisms by which METH causes neurodevelopmental defects have remained elusive. Here we utilized human cerebral organoids and single-cell RNA sequencing (scRNA-seq) to study the effects of prenatal METH exposure on fetal brain development. We analyzed 20,758 cells from eight untreated and six METH-treated cerebral organoids and found that the organoids developed from embryonic stem cells contained a diverse array of glial and neuronal cell types. We further identified transcriptionally distinct populations of astrocytes and oligodendrocytes within cerebral organoids. Treatment of organoids with METH-induced marked changes in transcription in multiple cell types, including astrocytes and neural progenitor cells. METH also elicited novel astrocyte-specific gene expression networks regulating responses to cytokines, and inflammasome. Moreover, upregulation of immediate early genes, complement factors, apoptosis, and immune response genes suggests a neuroinflammatory program induced by METH regulating neural stem cell proliferation, differentiation, and cell death. Finally, we observed marked METH-induced changes in neuroinflammatory and cytokine gene expression at the RNA and protein levels. Our data suggest that human cerebral organoids represent a model system to study drug-induced neuroinflammation at single-cell resolution.

Teratogen update: Amphetamines

Amphetamines are synthetic noncatecholamine sympathomimetic amines that act as psychostimulants. They have been prescribed for the treatment of attention-deficit/hyperactivity disorder (ADHD), narcolepsy, and additional health conditions. Amphetamines are also drugs of abuse. Some experimental animal studies suggested adverse developmental effects of amphetamines, including structural malformations. These effects were most often observed in experimental animals at higher dose levels than those used for treatment or abuse and at dose levels that produce maternal toxicity. Controlled studies of amphetamine use for the treatment of ADHD and other indications did not suggest that amphetamines are likely to cause structural malformations, although there are three studies associating medication for ADHD or methamphetamine abuse with gastroschisis. We did not locate studies on the neurobehavioral effects of prenatal exposures to therapeutic amphetamine use. Amphetamine abuse was associated with offspring neurobehavioral abnormalities, but lack of adequate adjustment for confounding interferes with interpretation of the associations. Adverse effects of methamphetamine abuse during pregnancy may be due to factors associated with drug abuse rather than methamphetamine itself. The adverse effects observed in methamphetamine abuse studies may not be extrapolatable to amphetamine medication use.

Structural brain network development in children following prenatal methamphetamine exposure

Brain imaging studies in children with prenatal methamphetamine exposure (PME) suggest structural and functional alterations of striatal, frontal, parietal, and limbic regions. However, no longitudinal studies have investigated changes in structural connectivity during the first 2 years of formal schooling. The aim of this study was to explore the effects of PME on structural connectivity of brain networks in children over the critical first 2 years of formal schooling when foundational learning takes place. Networks are expected to gradually increase in global connectedness while segregating into defined systems. Graph theoretical analysis was used to investigate changes in structural connectivity at age 6 and 8 years in children with and without PME. While healthy control children showed increased connectivity in frontal and limbic hubs over time, children with PME showed increased connectivity in the superior parietal cortex and striatum in their global network. Furthermore, compared to control children, those with PME were characterized by less change in segregation of structural networks over time. These findings are consistent with previous work on regions implicated in children with PME, but they additionally demonstrate alterations in structural connectivity between regions that underlie primary cognitive, behavioral, and emotional development. Understanding patterns of network development during critical periods in at-risk children may inform strategies for supporting this group of children in these developmental tasks important for lifelong brain health and development.

Influence of Prenatal Methamphetamine Abuse on the Brain

Methamphetamine (MA), a psychostimulant, has become a serious problem in recent years. It is one of the most widely abused psychostimulants in the world. In the Czech Republic, ecstasy is the most commonly used non-cannabis drug, followed by hallucinogenic fungi, LSD, MA, cocaine, and finally heroin. The prevalence of the usage of all addictive substances is highest in the age category of 15-34. Approximately 17.2% of registered drug addicts, both male and female, in the Czech Republic use MA as their first-choice drug. This group consists mostly of women who are unemployed and addicted to MA (85%). Almost half of the addicted women switched to MA from other drugs in the course of pregnancy. Psychostimulants such as amphetamine and its synthetic derivate MA induce feelings of calm and happiness by suppressing anxiety and depression. When MA is abused for longer periods, it mimics symptoms of mania and can lead to the development of psychosis. MA is often abused for its anorectic effect, its simple preparation, and compared to heroin and cocaine, its low price. There are significant differences in the susceptibility of users to the stimulant, with reactions to MA fluctuating from person to person. Molecular mechanisms related to the variable response among users might represent an explanation for increased addiction-associated bipolar disorder and psychosis. Currently, there is limited information regarding genetic mechanisms linked to these disorders and the transmission of drug addiction. As such, animal models of drug addiction represent significant sources of information and assets in the research of these issues. The aim of this review is to summarize the mechanism of action of methamphetamine and its effect on pregnant addicted women and their children, including a detailed description of the anatomical structures involved.

The multi-faceted impact of methamphetamine on Alzheimer's disease: From a triggering role to a possible therapeutic use

Although it has been initially synthesized for therapeutic purposes and currently FDA-approved and prescribed for obesity, attention-deficit/hyperactivity disorder, narcolepsy and depression, methamphetamine became a recreational drug that is nowadays massively manufactured illegally. Because it is a powerful and extremely addictive psychotropic agent, its abuse has turned out to become a major health problem worldwide. Importantly, the numerous effects triggered by this drug induce neurotoxicity in the brain ultimately leading to serious neurological impairments, tissue damage and neuropsychological disturbances that are reminiscent to most of the symptoms observed in Alzheimer's disease and other pathological manifestations in aging brain. In this context, there is a growing number of compelling evidence linking methamphetamine abuse with a higher probability of developing premature Alzheimer's disease and consequent neurodegeneration. This review proposes to establish a broad assessment of the effects that this drug can generate at the cellular and molecular levels in connection with the development of the age-related Alzheimer's disease. Altogether, the objective is to warn against the long-term effects that methamphetamine abuse may convey on young consumers and the increased risk of developing this devastating brain disorder at later stages of their lives, but also to discuss a more recently emerging concept suggesting a possible use of methamphetamine for treating this pathology under proper and strictly controlled conditions.

Family Environment, Neurodevelopmental Risk, and the Environmental Influences on Child Health Outcomes (ECHO) Initiative: Looking Back and Moving Forward

The family environment, with all its complexity and diverse components, plays a critical role in shaping neurodevelopmental outcomes in children. Herein we review several domains of the family environment (family socioeconomic status, family composition and home environment, parenting behaviors and interaction styles, parental mental health and functioning, and parental substance use) and discuss how these domains influence neurodevelopment, with particular emphasis on mental health outcomes. We also highlight a new initiative launched by the National Institutes of Health, the Environmental influences on Child Health Outcomes (ECHO) program. We discuss the role that ECHO will play in advancing our understanding of the impact of the family environment on children's risk for psychiatric outcomes. Lastly, we conclude with important unanswered questions and controversies in this area of research, highlighting how ECHO will contribute to resolving these gaps in our understanding, clarifying relationships between the family environment and children's mental health.

Developmental outcomes following prenatal exposure to methamphetamine: A Western Australian perspective

AIM

To describe neurodevelopmental outcomes among a cohort of Western Australian infants exposed to maternal methamphetamine use during pregnancy and to determine whether the Ages and Stages Questionnaire is a reliable screening tool for this population.

METHODS

Methamphetamine-using women were approached for participation when referred to the state-wide perinatal specialist drug and alcohol service for pregnancy care. Drug use during pregnancy was self-reported in each trimester using a standardised questionnaire. Ages and Stages Questionnaires were completed by infant care givers at 4 and 12 months, and development was formally assessed at 12 months using the Griffiths Mental Development Scales. Griffiths results for term-born infants in our cohort were compared to a Western Australian historical cohort of 443 healthy 1-2-year-olds.

RESULTS

A total of 112 methamphetamine-using pregnant women participated in the study, who gave birth to 110 live-born infants. Ages and Stages Questionnaires were completed for 89 (81%) and 78 (71%) of the infants at 4 and 12 months, respectively. The Ages and Stages assessment identified 30 infants (33.7%) as having a potential developmental delay at 4 months and 29 infants (38.7%) as having a potential developmental delay at 12 months. Griffiths assessments were performed on 64 (58%) of the infants, with a mean general quotient of 92.7. This was significantly lower in term-born babies compared to the historical cohort (who had a median general quotient of 113.0). There was a weak correlation between 12-month Ages and Stages scores and Griffiths general quotients (r = 0.322) and no correlation between 4-month Ages and Stages Questionnaire scores and later Griffiths results.

CONCLUSIONS

Infants born to women reporting methamphetamine use during pregnancy are at increased risk of developmental delay and may warrant enhanced developmental follow-up. However, they are a challenging group to follow due to complex psychosocial factors. Ages and Stages Questionnaires at 4 and 12 months were not helpful in screening for infants who had a developmental delay at 12 months.

Prolonged methamphetamine exposure during a critical period in neonatal Sprague Dawley rats does not exacerbate egocentric and allocentric learning deficits but increases reference memory impairments

Children exposed to methamphetamine (MA) in utero have cognitive deficits. MA administration in rats for 5-10 days between postnatal days (P)6 and 20 produces cognitive deficits. The purpose of this study was to determine if extending MA administration by 5 days within P6-20 would exacerbate allocentric (Morris water maze) and egocentric (Cincinnati water maze) learning deficits. Sprague Dawley female and male offspring (split-litter design) were administered saline (SAL) or MA (10 mg/kg) four times daily from P6 to 20 to create four groups: (a) SAL from P6 to 20, (b) MA from P6 to 20 (MA6-20), (c) MA from P6 to 15 (MA6-15), or (d) MA from P11 to 20 (MA11-20); the latter groups received saline on days they did not receive MA. Egocentric, allocentric, and conditioned freezing tests began on P60. The MA6-15 and MA6-20 groups showed egocentric deficits, all MA groups had allocentric deficits but no differences in conditioned freezing compared with SAL controls. The MA6-15 and MA6-20 groups had similar deficits in learning and memory that were larger than in the MA11-20 group. Learning in both mazes was sex dependent, but no interactions with MA were found. The data demonstrate that extending the exposure period of MA beyond the sensitive periods (P6-15 and P11-20) did not exacerbate the cognitive deficits.

The causal web of foetal alcohol spectrum disorders: a review and causal diagram

Foetal alcohol spectrum disorders (FASDs) are a leading cause of developmental disability. Prenatal alcohol use is the sole necessary cause of FASD, but it is not always sufficient. Multiple factors influence a child's susceptibility to FASD following prenatal alcohol exposure. Much of the FASD risk factor literature has been limited to discussions of association, rather than causation. While knowledge of predictor variables is important for identifying who is most at risk of FASD and for targeting interventions, causal knowledge is important for identifying effective mechanisms for prevention and intervention programmes. We conducted a systematic search and narrative synthesis of the evidence and used this to create a causal diagram (directed acyclic graph; DAG) to describe the causal pathways to FASD. Our results show that the aetiology of FASD is multifaceted and complex. FASD risk is determined by a range of lifestyle, sociodemographic, maternal, social, gestational, and genetic factors. The causal diagram that we present in this review provides a comprehensive summary of causal risk factors for FASD and can be used as a tool to inform data collection and statistical modelling strategies to minimise bias in future studies of FASD.

ADHD symptoms induced by prenatal methamphetamine exposure

Methamphetamine is commonly used psychostimulant in the Czech Republic and is often abused by pregnant women. Methamphetamine may cause abnormalities in placenta and umbilical cord that results in hypoxia and malnutrition. ADHD is a mental disorder with a heterogeneous origin. The number of patients suffering from ADHD is growing. The pathophysiological mechanisms causing ADHD have not yet been clarified. There are very few rat models for ADHD and include genetic models, chemically induced models (ethanol, nicotine, PCBs, 6-hydroxydopamine lesion) or environmentally induced models (anoxia). The aim of the present study was to test prenatal methamphetamine exposure (5 mg/kg) as a potential novel animal model for ADHD. We found that adult male offspring prenatally exposed to methamphetamine presented hyperactivity while exploring novel environments. Together with cognition changes found in our previous studies, these might represent symptoms similar to those seen in ADHD. More experiments are planned to investigate our hypothesis.

Prenatal Exposure to Methamphetamine: Up-Regulation of Brain Receptor Genes

Methamphetamine (METH) is a widespread illicit drug. If it is taken by pregnant women, it passes through the placenta and just as it affects the mother, it can impair the development of the offspring. The aim of our study was to identify candidates to investigate for changes in the gene expression in the specific regions of the brain associated with addiction to METH in rats. We examined the various areas of the central nervous system (striatum, hippocampus, prefrontal cortex) for signs of impairment in postnatal day 80 in experimental rats, whose mothers had been administered METH (5 mg/kg/day) during the entire gestation period. Changes in the gene expression at the mRNA level were determined by two techniques, microarray and real-time PCR. Results of two microarray trials were evaluated by LIMMA analysis. The first microarray trial detected either up-regulated or down-regulated expression of 2189 genes in the striatum; the second microarray trial detected either up-regulated or down-regulated expression of 1344 genes in the hippocampus of prenatally METH-exposed rats. We examined the expression of 10 genes using the real-time PCR technique. Differences in the gene expression were counted by the Mann–Whitney U-test. Significant changes were observed in the cocaine- and amphetamine-regulated transcript prepropeptide, tachykinin receptor 3, dopamine receptor D3 gene expression in the striatum regions, in the glucocorticoid nuclear receptor Nr3c1 gene expression in the prefrontal cortex and in the carboxylesterase 2 gene expression in the hippocampus of prenatally METH-exposed rats. The microarray technique also detected up-regulated expression of trace amine-associated receptor 7 h gene in the hippocampus of prenatally METH-exposed rats. We have identified susceptible genes; candidates for the study of an impairment related to methamphetamine addiction in the specific regions of the brain.

Prenatal drug exposure from infancy through emerging adulthood: Results from neuroimaging

Prenatal drug exposure may have important repercussions across the lifespan for cognition and behavior. While alcohol is a recognized teratogen, the influences of other substances may also be substantial. The neural underpinnings of the influences of prenatal drug exposure have been examined using longitudinal approaches and multiple imaging techniques. Here we review the existing literature on the neural correlates of prenatal drug exposure. We focused the review on studies that have employed functional neuroimaging and electroencephalography and on substances other than alcohol. We also framed the review through the lens of four developmental life stages (infancy, childhood, adolescence and emerging adulthood). We included papers that have examined any drug use, including tobacco, opiates, cocaine, marijuana, methamphetamines, or polysubstance use. Data suggest that prenatal drug exposure has long-lasting, deleterious influences on cognition and reward processing in infancy and childhood that persist into adolescence and emerging adulthood and may underlie some behavioral tendencies, such as increased externalizing and risk-taking behaviors, seen in these groups.

Stimulant Use in Pregnancy: An Under-recognized Epidemic Among Pregnant Women

Stimulant use, including cocaine, methamphetamines, ecstasy, and prescription stimulants, in pregnancy is increasingly common. In the United States, stimulants are the second most widely used and abused substances during pregnancy and pregnant women using stimulants in pregnancy are at increased risk of adverse perinatal, neonatal, and childhood outcomes. In this review, we describe the pharmacology, pathophysiology, and epidemiology of stimulants, summarize the maternal and neonatal effects of perinatal stimulant use, and outline treatment options for stimulant use disorders among pregnant women. Development of effective treatment strategies for stimulant use disorders identified among pregnant women are urgently needed.

The cellular basis of fetal endoplasmic reticulum stress and oxidative stress in drug-induced neurodevelopmental deficits

Prenatal substance exposure is a growing public health concern worldwide. Although the opioid crisis remains one of the most prevalent addiction problems in our society, abuse of cocaine, methamphetamines, and other illicit drugs, particularly amongst pregnant women, are nonetheless significant and widespread. Evidence demonstrates prenatal drug exposure can affect fetal brain development and thus can have long-lasting impact on neurobehavioral and cognitive performance later in life. In this review, we highlight research examining the most prevalent drugs of abuse and their effects on brain development with a focus on endoplasmic reticulum stress and oxidative stress signaling pathways. A thorough exploration of drug-induced cellular stress mechanisms during prenatal brain development may provide insight into therapeutic interventions to combat effects of prenatal drug exposure.

Early Postnatal Stress Impairs Cognitive Functions of Male Rats Persisting Until Adulthood

Methamphetamine (MA) is the most abused “hard” illicit drug in the Czech Republic. Drugs abused during pregnancy are not hazardous merely to the mother, but also to developing fetuses. The offspring of drug-addicted mothers are also often exposed to perinatal stressors that may impair brain development of affected progeny. The present study examines the effect of perinatal stressors and drug exposure on cognitive function in male progeny. In the present study, rat mothers were divided into three groups according to drug treatment during pregnancy: controls (C); saline (SA, s.c., 1 ml/kg); MA (s.c., 5 mg/ml/kg). Litters were divided into two groups according to postnatal stressors: non-stressed controls (N); Maternal separation (MS). For evaluation of learning and memory, adult male progeny were tested in the Morris Water Maze (MWM). Our results revealed no significant effects caused by prenatal drug or prenatal stress exposure. On the other hand, chronic postnatal stress, mediated by MS, significantly impaired learning on the Place Navigation test. In addition, MS was associated with changes in search strategies on the Place Navigation, Probe, and Memory Recall tests. Specifically, postnatal stress increased thigmotaxis, indicating less awareness of the hidden platform. In conclusion, the present study provides evidence that exposure to early postnatal stress significantly impairs cognitive functions of male rats, which persists into adulthood.

Substance use in pregnancy: The medical challenge

Substance use contributes significantly to the global burden of disease. Growing numbers of women use nicotine, alcohol, and illicit substances. Women are the most vulnerable to problematic substance use in their reproductive years. The first 1000 days of life, starting at conception, have been established as a critical window of time for long-term health and development. Substance use in pregnancy is associated with negative pregnancy and child health outcomes. The impact of antenatal substance use on these outcomes needs to be considered within a challenging and complex context. This review provides an overview of the current literature on the impact of substances on pregnancy and child outcomes as well as the evidence and guidelines on screening and interventions for women using substances during pregnancy.

Prenatal methamphetamine exposure is associated with corticostriatal white matter changes in neonates

Diffusion tensor imaging (DTI) studies have shown that prenatal exposure to methamphetamine is associated with alterations in white matter microstructure, but to date no tractography studies have been performed in neonates. The striato-thalamo-orbitofrontal circuit and its associated limbic-striatal areas, the primary circuit responsible for reinforcement, has been postulated to be dysfunctional in drug addiction. This study investigated potential white matter changes in the striatal-orbitofrontal circuit in neonates with prenatal methamphetamine exposure. Mothers were recruited antenatally and interviewed regarding methamphetamine use during pregnancy, and DTI sequences were acquired in the first postnatal month. Target regions of interest were manually delineated, white matter bundles connecting pairs of targets were determined using probabilistic tractography in AFNI-FATCAT, and fractional anisotropy (FA) and diffusion measures were determined in white matter connections. Regression analysis showed that increasing methamphetamine exposure was associated with reduced FA in several connections between the striatum and midbrain, orbitofrontal cortex, and associated limbic structures, following adjustment for potential confounding variables. Our results are consistent with previous findings in older children and extend them to show that these changes are already evident in neonates. The observed alterations are likely to play a role in the deficits in attention and inhibitory control frequently seen in children with prenatal methamphetamine exposure.

Brief screening for cognitive impairment in addictive disorders

Chronic use of mind altering substances can lead to a wide variety of neuropsychological deficits, affecting the domains of attention, learning, memory, reasoning. Executive functions such as working memory, cognitive flexibility and inhibitory control may specifically be impaired. These deficits can impact engagement in effective psychosocial interventions. Mild to moderate cognitive dysfunction may not be picked up in routine clinical examination or through commonly used tests like the mini-mental state examination (MMSE). Detailed neuropsychological tests, although extremely valuable, are time and human-resource intensive and are not readily available to the clinician. This study attempted to devise a brief cognitive screen (BCS- AUD) for alcohol use disorders. Ninety subjects who fulfilled ICD-10 criteria for alcohol use disorders were assessed on the MMSE and selective tests from the NIMHANS neuropsychological battery. While 79 (87.78%) of patients had adequate scores on the MMSE (>25), cognitive deficits were noted with relatively high frequency on finger tapping (92.22-93.33%), auditory verbal learning test delayed recall AVLTDR (37-63%) and Tower of London 5 move subtest (42%). Statistically significant associations were found between MMSE and Digit symbol total time (0.05), Finger tapping right hand (0.01), Tower of London total number of problems solved with minimum moves (TNPSMM) (0.05), Verbal working memory two back hits (VM2BKHIT) (0.01), AVLTDR (0.01), and complex figure test-copy (0.01). Principal component analysis helped to identify three tests that merited inclusion in the BCS-AUD, namely Finger Tapping Test, Verbal Working Memory N Back Test and Auditory Verbal Test (AVLT). The utility of the BCS-AUD in identifying cognitive dysfunction in other substance use disorders needs to be examined. Patients rating positive on the cognitive screener would require in-depth evaluation, monitoring and remediation.

Cognitive outcomes in prenatal methamphetamine exposed children aged six to seven years

BACKGROUND

Methamphetamine use among pregnant women has become a significant problem. Research delineating the cognitive outcomes of prenatal methamphetamine exposure (PME) in early childhood is limited, however. The aim of this study was to examine effects of PME on cognition in six-to-seven-year-old children.

METHODS

PME children (n=23) and unexposed controls (n=22) completed a battery of neurocognitive tests, which included the Kaufman Assessment Battery for Children, Boston Naming Test, Beery Developmental Test of Visual-Motor Integration, and Grooved Pegboard Test.

RESULTS

Independent samples t-tests revealed that PME children scored significantly worse than controls on the measures of IQ, learning and memory, confrontation naming, visual-motor integration, and fine motor coordination. Hierarchical regression analyses that included potential confounding sociodemographic, co-exposure and anthropometric variables confirmed that PME impacts negatively on cognitive performance.

CONCLUSIONS

The study confirms that PME has deleterious effects on cognition in several broad cognitive domains, likely by altering underlying brain circuitry in development. These effects may be particularly pronounced at the time when children enter formal schooling. Extended follow-ups into late childhood might help elucidate the developmental trajectory of cognitive dysfunction in PME, and subsequent effects on everyday functioning.

Neurocognitive and neurodevelopmental impact of prenatal methamphetamine exposure: A comparison study of prenatally exposed children with nonexposed ADHD peers

Prenatal methamphetamine exposure has become an increasingly pervasive concern, especially in rural-based populations and populations of lower socioeconomic status. While research has begun to highlight the effects of prenatal methamphetamine exposure, the long-term impact of this exposure remains an under-investigated topic. This study attempts to investigate the neurocognitive and neurodevelopmental effects of prenatal methamphetamine exposure by comparing the index and full-scale IQ scores on the WISC-IV between a sample of clinically referred children prenatally exposed to methamphetamine (N = 80) and a sample of clinically referred nonexposed children diagnosed with ADHD (N = 44). Children prenatally exposed to methamphetamine showed significantly lower scores on all WISC-IV domains when compared to peers with ADHD. When taking into account polysubstance exposure to alcohol, these differences remained statistically significant, with the exception of the Processing Speed Index (PSI); children reported to have been prenatally exposed to methamphetamine and to alcohol (PME) remained below ADHD peers on all other WISC-IV index scores. Within the prenatally exposed sample, regression analyses indicated that age was a significant negative predictor of PSI scores. Overall findings suggest that prenatal methamphetamine exposure is associated with a notable cognitive impact independent of polysubstance exposure to alcohol, and that the impact of this exposure on processing speed skills may become more pronounced with age.

Prenatal methamphetamine exposure is associated with reduced subcortical volumes in neonates

OBJECTIVES

Prenatal exposure to methamphetamine is associated with a range of neuropsychological, behavioural and cognitive deficits. A small number of imaging studies suggests that these may be mediated by neurostructural changes, including reduced volumes of specific brain regions. This study investigated potential volumetric changes in the brains of neonates with prenatal methamphetamine exposure. To our knowledge no previous studies have examined methamphetamine effects on regional brain volumes at this age.

STUDY DESIGN

Mothers were recruited antenatally and interviewed regarding methamphetamine use during pregnancy. Mothers in the exposure group reported using methamphetamine≥twice/month during pregnancy; control infants had no exposure to methamphetamine or other drugs and minimal exposure to alcohol. MRI scans were performed in the first postnatal month, following which anatomical images were processed using FreeSurfer. Subcortical and cerebellar regions were manually segmented and their volumes determined using FreeView. Pearson correlations were used to analyse potential associations between methamphetamine exposure and regional volumes. The associations between methamphetamine exposure and regional volumes were then examined adjusting for potential confounding variables.

RESULTS

Methamphetamine exposure was associated with reduced left and right caudate and thalamus volumes. The association in the right caudate remained significant following adjustment for potential confounding variables.

CONCLUSIONS

Our findings showing reduced caudate and thalamus volumes in neonates with prenatal methamphetamine exposure are consistent with previous findings in older exposed children, and demonstrate that these changes are already detectable in neonates. Continuing research is warranted to examine whether reduced subcortical volumes are predictive of cognitive, behavioural and affective impairment in older children.

Lower Fractional Anisotropy in the Gray Matter of Amygdala-Hippocampus-Nucleus Accumbens Circuit in Methamphetamine Users: an In Vivo Diffusion Tensor Imaging Study

The basolateral amygdala (BLA), hippocampal ventral subiculum, and nucleus accumbens (NAc) comprise the amygdala-hippocampus-NAc (AHN) circuit, which is implicated in drug seeking and reward. The goal of this study was to evaluate microstructural changes and relevant clinical features of the AHN circuit gray matter (GM) in methamphetamine (MA) users using diffusion tensor imaging (DTI). Thirty MA users and 30 age-matched normal volunteers underwent 3-T MR imaging to obtain structural T1-weighted images and DTI data. Freesurfer software was used to automatically segment the NAc and subiculum. A Jülich probability map was employed to parcellate the BLA. Fractional anisotropy (FA) and mean diffusivity (MD) maps were generated and non-linearly coregistered to structural space. DTI measures of the AHN circuit GM were compared between MA users and controls using repeated measures analysis of variance. Correlation analyses were performed between DTI measures and clinical characteristics. Anatomical correlations between the NAc and BLA/subiculum in both groups were assessed using correlation analyses. The MA group had significant lower FA in the bilateral BLA, subiculum, and NAc. Higher total MA dose corresponded with lower FA in all three structures. Hamilton Anxiety Rating Scale scores negatively correlated with the right subiculum FA. Lower left BLA FA was associated with higher thinking disorder and hostile-suspicion factor scores. Left BLA FA was significantly associated with bilateral NAc FA in MA users. Those findings provided neuroimaging evidence of MA-induced microstructural impairment in the AHN circuit GM. Enhanced anatomical correlations between the left BLA and bilateral NAc may be part of the mechanism of MA intake relapse and for development of psychosis.

Fetal oxidative stress mechanisms of neurodevelopmental deficits and exacerbation by ethanol and methamphetamine

In utero exposure of mouse progeny to alcohol (ethanol, EtOH) and methamphetamine (METH) causes substantial postnatal neurodevelopmental deficits. One emerging pathogenic mechanism underlying these deficits involves fetal brain production of reactive oxygen species (ROS) that alter signal transduction, and/or oxidatively damage cellular macromolecules like lipids, proteins, and DNA, the latter leading to altered gene expression, likely via non-mutagenic mechanisms. Even physiological levels of fetal ROS production can be pathogenic in biochemically predisposed progeny, and ROS formation can be enhanced by drugs like EtOH and METH, via activation/induction of ROS-producing NADPH oxidases (NOX), drug bioactivation to free radical intermediates by prostaglandin H synthases (PHS), and other mechanisms. Antioxidative enzymes, like catalase in the fetal brain, while low, provide critical protection. Oxidatively damaged DNA is normally rapidly repaired, and fetal deficiencies in several DNA repair proteins, including oxoguanine glycosylase 1 (OGG1) and breast cancer protein 1 (BRCA1), enhance the risk of drug-initiated postnatal neurodevelopmental deficits, and in some cases deficits in untreated progeny, the latter of which may be relevant to conditions like autism spectrum disorders (ASD). Risk is further regulated by fetal nuclear factor erythroid 2-related factor 2 (Nrf2), a ROS-sensing protein that upregulates an array of proteins, including antioxidative enzymes and DNA repair proteins. Imbalances between conceptal pathways for ROS formation, versus those for ROS detoxification and DNA repair, are important determinants of risk. Birth Defects Research (Part C) 108:108-130, 2016. © 2016 Wiley Periodicals, Inc.

Does effect from developmental methamphetamine exposure on spatial learning and memory depend on stage of neuroontogeny?

Psychostimulants, including methamphetamine (MA), have neurotoxic effect, especially, if they are targeting CNS during its critical periods of development. The present study was aimed to examine cognitive changes after prenatal and neonatal MA treatment in combination with chronic MA exposure in adulthood of male rats. Eight groups of male rats were tested in adulthood: males whose mothers were exposed to MA (5 mg/kg) or saline (SA, 1 ml/kg) during the first half of gestation period (GD 1-11), the second half of gestation period (GD 12-22) and neonatal period (PD 1-11). In addition, we compared indirect neonatal application via the breast milk with the group of rat pups that received MA or SA directly by injection (PD 1-11). Males were tested in adulthood for cognitive changes in the Morris Water Maze (MWM). MWM experiment lasted for 12 days: Learning (Day 1-6), Probe test (Day 8) and Retrieval Memory test (Day 12). Each day of the MWM animals were injected with MA (1 mg/kg) or SA (1 ml/kg). Prenatal MA exposure did not induce changes in learning abilities of male rats, but neonatal exposure to MA leads to an increase search errors and latencies to find the hidden platform. Prenatal and also neonatal MA exposure impaired cognitive ability to remember the position of the platform in Retrieval Memory test in adulthood. Animals exposed to the prenatal treatment within the second half of gestation (ED 12-22) swam longer, slower and spent more time to find the hidden platform in Retrieval Memory test than animals exposed throughout other periods. The present study demonstrated that stage of development is crucial for determination the cognitive deficits induced by prenatal or neonatal MA exposure.