Serotonin, pregnancy and increased autism prevalence: Is there a link?

Neonatal treatment with para-chlorophenylalanine (pCPA) induces adolescent hyperactivity associated with changes in the paraventricular nucleus Crh and Trh expressions

Disruption of the brain serotoninergic (5-HT) system during development induces long-lasting changes in molecular profile, cytoarchitecture, and function of neurons, impacting behavioral regulation throughout life. In male and female rats, we investigate the effect of neonatal tryptophan hydroxylase (TPH) inhibition by using para-chlorophenylalanine (pCPA) on the expression of 5-HTergic system components and neuropeptides related to adolescent social play behavior regulation. We observed sex-dependent 5-HT levels decrease after pCPA-treatment in the dorsal raphe nucleus (DRN) at 17 and 35 days. Neonatal pCPA-treatment increased playing, social and locomotory behaviors assessed in adolescent rats of both sexes. The pCPA-treated rats demonstrated decreased Crh (17 days) and increased Trh (35 days) expression in the hypothalamic paraventricular nucleus (PVN). There was sex dimorphism in Htr2c (17 days) and VGF (35 days) in the prefrontal cortex, with the females expressing higher levels of it than males. Our results indicate that neonatal pCPA-treatment results in a long-lasting and sex-dependent DRN 5-HT synthesis changes, decreased Crh, and increased Trh expression in the PVN, resulting in a hyperactivity-like phenotype during adolescence. The present work demonstrates that the impairment of TPH function leads to neurobehavioral disorders related to hyperactivity and impulsivity, such as attention deficit hyperactivity disorder (ADHD).

Cannabis and Pregnancy: A Review

Importance

Prenatal cannabis use is rising and is a major public health issue. Cannabis use in pregnancy and during lactation has been associated with increased maternal and offspring morbidity and mortality.

Objective

This review aims to summarize the existing literature and current recommendations for cannabis use during pregnancy or lactation.

Evidence Acquisition

A PubMed, Cochrane Library, and Google Scholar literature search using the following terms was performed to gather relevant data: "cannabis," "cannabinoid," "delta-9-tetrahydrocannabinol," "THC," "cannabidiol," "fetal outcomes," "perinatal outcomes," "pregnancy," and "lactation."

Results

Available studies on cannabis use in pregnancy and during lactation were reviewed and support an association with increased risk of preterm birth, neonatal intensive care unit admission, low birth weight, and small-for-gestational-age infants.

Conclusion and Relevance

There is a critical need for research on the effects of cannabis use in pregnancy and during lactation. This is a necessary first step before furthering patient education, developing interventions, and targeting antenatal surveillance to ameliorate the adverse impacts on maternal and fetal health.

Serotonin Receptors as Therapeutic Targets for Autism Spectrum Disorder Treatment

Autism spectrum disorder (ASD) is a group of neurodevelopmental disorders characterized by repetitive and stereotyped behaviors as well as difficulties with social interaction and communication. According to reports for prevalence rates of ASD, approximately 1~2% of children worldwide have been diagnosed with ASD. Although there are a couple of FDA (Food and Drug Administration)—approved drugs for ASD treatment such as aripiprazole and risperidone, they are efficient for alleviating aggression, hyperactivity, and self-injury but not the core symptoms. Serotonin (5-hydroxytryptamine, 5-HT) as a neurotransmitter plays a crucial role in the early neurodevelopmental stage. In particular, 5-HT has been known to regulate a variety of neurobiological processes including neurite outgrowth, dendritic spine morphology, shaping neuronal circuits, synaptic transmission, and synaptic plasticity. Given the roles of serotonergic systems, the 5-HT receptors (5-HTRs) become emerging as potential therapeutic targets in the ASD. In this review, we will focus on the recent development of small molecule modulators of 5-HTRs as therapeutic targets for the ASD treatment.

Discovery of G Protein-Biased Antagonists against 5-HT7R

5-HT₇R belongs to a family of G protein-coupled receptors and is associated with a variety of physiological processes in the central nervous system via the activation of the neurotransmitter serotonin (5-HT). To develop selective and biased 5-HT₇R ligands, we designed and synthesized a series of pyrazolyl-diazepanes 2 and pyrazolyl-piperazines 3, which were evaluated for binding affinities to 5-HTR subtypes and functional selectivity for G protein and β-arrestin signaling pathways of 5-HT₇R. Among them, 1-(3-(3-chlorophenyl)-1H-pyrazol-4-yl)-1,4-diazepane 2c showed the best binding affinity for 5-HT₇R and selectivity over other 5-HTR subtypes. It was also revealed as a G protein-biased antagonist. The self-grooming behavior test was performed with 2c in vivo with Shank3^-/- transgenic (TG) mice, wherein 2c significantly reduced self-grooming duration time to the level of wild-type mice. The results suggest that 5-HT₇R could be a potential therapeutic target for treating autism spectrum disorder stereotypy.

Serotonin transporter availability in adults with autism-a positron emission tomography study

Impairments in social interaction and communication, in combination with restricted, repetitive behaviors and interests, define the neurodevelopmental diagnosis of autism spectrum disorder (ASD). The biological underpinnings of ASD are not well known, but the hypothesis of serotonin (5-HT) involvement in the neurodevelopment of ASD is one of the longest standing. Reuptake through the 5-HT transporter (5-HTT) is the main pathway decreasing extracellular 5-HT in the brain and a marker for the 5-HT system, but in vivo investigations of the 5-HTT and the 5-HT system in ASD are scarce and so far inconclusive. To quantify possible alterations in the 5-HT system in ASD, we used positron emission tomography and the radioligand [¹¹C]MADAM to measure 5-HTT availability in the brain of 15 adults with ASD and 15 controls. Moreover, we examined correlations between regional 5-HTT availability and behavioral phenotype assessments regarding ASD core symptoms. In the ASD group, we found significantly lower 5-HTT availability in total gray matter, brainstem, and 9 of 18 examined subregions of gray matter. In addition, several correlations between regional 5-HTT availability and social cognitive test performance were found. The results confirm the hypothesis that 5-HTT availability is lower in the brain of adult individuals with ASD, and are consistent with the theory of 5-HT involvement in ASD neurodevelopment. The findings endorse the central role of 5-HT in the physiology of ASD, and confirm the need for a continued investigation of the 5-HT system in order to disentangle the biology of ASD.

Hypertensive disorders of pregnancy and the risk of offspring depression in childhood: Findings from the Avon Longitudinal Study of Parents and Children

Hypertensive disorders of pregnancy (HDP) may increase the risk of offspring depression in childhood. Low birth weight is also associated with increased risk of mental health problems, including depression. This study sought to investigate (a) whether there is an association between HDP and the risk of depression in childhood and (b) whether low birth weight mediates this association. The current study is based on the Avon Longitudinal Study of Parents and Children (ALSPAC), a prospective, population-based study that has followed a cohort of offspring since their mothers were pregnant (n = 6,739). Depression at the age of 7 years was diagnosed using parent reports via the Development and Well-Being Assessment (DAWBA). Log-binomial regression and mediation analyses were used. Children exposed to HDP were 2.3 times more likely to have a depression diagnosis compared with nonexposed children, adjusted Risk Ratio [RR], 2.31; 95% CI, [1.20, 4.47]. Low birth weight was a weak mediator of this association. Results were adjusted for confounding variables including antenatal depression and anxiety during pregnancy.This study suggests that fetal exposure to maternal hypertensive disorders of pregnancy increased the risk of childhood depression. The study adds to the evidence suggesting that the uterine environment is a critical determinant of neurodevelopmental and psychiatric outcomes.

Comparative psychopharmacology of autism and psychotic-affective disorders suggests new targets for treatment

The first treatments showing effectiveness for some psychiatric disorders, such as lithium for bipolar disorder and chlorpromazine for schizophrenia, were discovered by accident. Currently, psychiatric drug design is seen as a scientific enterprise, limited though it remains by the complexity of brain development and function. Relatively few novel and effective drugs have, however, been developed for many years. The purpose of this article is to demonstrate how evolutionary biology can provide a useful framework for psychiatric drug development. The framework is based on a diametrical nature of autism, compared with psychotic-affective disorders (mainly schizophrenia, bipolar disorder and depression). This paradigm follows from two inferences: (i) risks and phenotypes of human psychiatric disorders derive from phenotypes that have evolved along the human lineage and (ii) biological variation is bidirectional (e.g. higher vs lower, faster vs slower, etc.), such that dysregulation of psychological traits varies in two opposite ways. In this context, the author review the evidence salient to the hypothesis that autism and psychotic-affective disorders represent diametrical disorders in terms of current, proposed and potential psychopharmacological treatments. Studies of brain-derived neurotrophic factor, the PI3K pathway, the NMDA receptor, kynurenic acid metabolism, agmatine metabolism, levels of the endocannabinoid anandamide, antidepressants, anticonvulsants, antipsychotics, and other treatments, demonstrate evidence of diametric effects in autism spectrum disorders and phenotypes compared with psychotic-affective disorders and phenotypes. These findings yield insights into treatment mechanisms and the development of new pharmacological therapies, as well as providing an explanation for the longstanding puzzle of antagonism between epilepsy and psychosis. Lay Summary: Consideration of autism and schizophrenia as caused by opposite alterations to brain development and function leads to novel suggestions for pharmacological treatments.

Annual Research Review: Maternal antidepressant use during pregnancy and offspring neurodevelopmental problems - a critical review and recommendations for future research

Children of women treated with antidepressants during pregnancy are more likely to develop neurodevelopmental problems than are unexposed children. Associations between prenatal antidepressant exposure and neurodevelopmental problems could reflect a causal effect or could be partially or fully explained by other factors that differ between exposed and unexposed offspring, including having mothers with conditions requiring antidepressant treatment (e.g. depression), environmental risk factors, and/or genetic risk factors shared across disorders. This translational review aims to provide a brief overview of findings from rodent experiments and critically evaluate observational studies in humans to assess the extent to which associations between prenatal antidepressant exposure and neurodevelopmental problems are due to causal mechanisms versus other influences. We focus our review on two important neurodevelopmental outcomes - autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD). In general, rodent studies have reported adverse effects of perinatal antidepressant exposure on neurodevelopment. Between-species differences raise questions about the generalizability of these findings to humans. Indeed, converging evidence from studies using multiple designs and approaches suggest that observed associations between prenatal antidepressant exposure and neurodevelopmental problems in humans are largely due to confounding factors. We also provide specific recommendations for future research. Animal research should explicitly evaluate the impact of timing of exposure and dosage of medications, as well as better map outcome measures in rodents to human neurodevelopmental problems. Observational studies should investigate specific confounding factors, specific antidepressant drugs and classes, the potential impact of timing of exposure, and a wider range of other potential offspring outcomes. The findings summarized in this review may help women and their doctors make informed decisions about antidepressant use during pregnancy by providing reassurance that use of these medications during pregnancy is unlikely to substantially increase the risk of ASD and ADHD.

Risk of autism spectrum disorder in offspring following paternal use of selective serotonin reuptake inhibitors before conception: a population-based cohort study

OBJECTIVE

The present study aimed to examine the association between paternal selective serotonin reuptake inhibitor (SSRI) use before conception and the risk of autism spectrum disorder (ASD) in offspring.

DESIGN

A population-based cohort study.

METHODS

We conducted a cohort study of 669 922 children born from 1998 to 2008, with follow-up throughout 2013. Based on Danish national registers, we linked information on paternal use of SSRIs, ASD diagnosed in children and a range of potential confounders. The children whose fathers used SSRIs during the last 3 months prior to conception were identified as the exposed. Cox regression model was used to estimate the HR for ASD in children.

RESULTS

Compared with unexposed children, the exposed had a 1.62-fold higher risk of ASD (95% CI 1.33 to 1.96) and the risk attenuated after adjusting for potential confounders, especially fathers' psychiatric conditions (HR=1.43, 95% CI 1.18 to 1.74). When extending the exposure window to 1 year before conception, the increased risk persisted in children of fathers using SSRIs only from the last year until the last 3 months prior to conception (HR=1.54, 95% CI 1.21 to 1.94) but not in children of fathers using SSRIs only during the last 3 months prior to conception (HR=1.17, 95% CI 0.75 to 1.82). We also performed stratified analyses according to paternal history of affective disorders and observed no increased ASD risk among children whose father had affective disorders. Besides, the sibling analysis showed that the ASD risk did not increase among exposed children compared with their unexposed siblings.

CONCLUSIONS

The mildly increased risk of ASD in the offspring associated with paternal SSRI use before conception may be attributable to paternal underlying psychiatric indications related to SSRI use or other unmeasured confounding factors.

Is there sexual dimorphism of hyperserotonemia in autism spectrum disorder?

Approximately 30% of individuals with autism spectrum disorder (ASD) have elevated whole blood serotonin (5-HT) levels. Genetic linkage and association studies of ASD and of whole blood 5-HT levels as a quantitative trait have revealed sexual dimorphism. Few studies have examined the presence of a sex difference on hyperserotonemia within ASD. To assess whether the rate of hyperserotonemia is different in males than in females with ASD, we measured whole blood 5-HT levels in 292 children and adolescents with ASD, the largest sample in which this biomarker has been assessed. Based upon previous work suggesting that hyperserotonemia is more common prior to puberty, we focused our analysis on the 182 pre-pubertal children with ASD. 42% of pre-pubertal participants were within the hyperserotonemia range. In this population, we found that males were significantly more likely to manifest hyperserotonemia than females (P = 0.03). As expected, no significant difference was found in the post-pubertal population. Additional work will be needed to replicate this intriguing finding and to understand whether it could potentially explain differences in patterns of ASD risk between males and females. Autism Res 2017, 10: 1417-1423. © 2017 International Society for Autism Research, Wiley Periodicals, Inc.

[Affective disorders during pregnancy : Therapy with antidepressants and mood stabilizers]

BACKGROUND

It is not rare that the first manifestation or relapse of an affective disorder occurs during pregnancy. Should a pharmacological treatment be indicated, the selection of a suitable substance should be made on a basis which is as safe as possible. Even when treating women of childbearing age it should be assured that the psychotropic drug selected is safe to use during pregnancy as a high percentage of pregnancies are unplanned.

OBJECTIVE

When assessing the risks and benefits of psychopharmacotherapy in women who are or wish to get pregnant, not only the exposure of the child to potentially teratogenic drug effects but also potential complications during or after pregnancy and long-term neuropsychological issues need to be addressed.

METHODS

This article provides an overview of the currently available literature on the use of antidepressants and mood stabilizers during pregnancy.

RESULTS

A growing body of increasingly reliable data for many antidepressants and mood stabilizers are available, which allow a good prediction of their suitability for use during pregnancy and lactation.

CONCLUSION

When treating affective disorders during pregnancy an individual assessment of the benefits and risks for mother and child is required. The benefit of an appropriate treatment for the mother by including medication which may be potentially harmful to the child versus the risk of an insufficient treatment for the mother by excluding medication which may be potentially harmful to both the mother and the child need to be weighed up. When a suitable psychopharmacotherapy during pregnancy has been selected, the risk for mother and child can be minimized by incorporation of therapeutic drug monitoring.

Annual Research Review: The role of the environment in the developmental psychopathology of autism spectrum condition

BACKGROUND

Although autism spectrum condition (ASC) is strongly genetic in origin, accumulating evidence points to the critical roles of various environmental influences on its emergence and subsequent developmental course.

METHODS

A developmental psychopathology framework was used to synthesise literature on environmental factors associated with the onset and course of ASC (based on a systematic search of the literature using PubMed, PsychInfo and Google Scholar databases). Particular emphasis was placed on gene-environment interplay, including gene-environment interaction (G × E) and gene-environment correlation (rGE).

RESULTS

Before conception, advanced paternal and maternal ages may independently enhance offspring risk for ASC. Exogenous prenatal risks are evident (e.g. valproate and toxic chemicals) or possible (e.g. selective serotonin reuptake inhibitors), and processes endogenous to the materno-foeto-placental unit (e.g. maternal diabetes, enhanced steroidogenic activities and maternal immune activation) likely heighten offspring vulnerability to ASC. Folate intake is a prenatal protective factor, with a particular window of action around 4 weeks preconception and during the first trimester. These prenatal risks and protective mechanisms appear to involve G × E and potentially rGE. A variety of perinatal risks are related to offspring ASC risk, possibly reflecting rGE. Postnatal social factors (e.g. caregiver-infant interaction, severe early deprivation) during the first years of life may operate through rGE to influence the likelihood of manifesting a full ASC phenotype from a 'prodromal' phase (a proposal distinct to the discredited and harmful 'refrigerator mother hypothesis'); and later postnatal risks, after the full manifestation of ASC, shape life span development through transactions mediated by rGE. There is no evidence that vaccination is a postnatal risk for ASC.

CONCLUSIONS

Future investigations should consider the specificity of risks for ASC versus other atypical neurodevelopmental trajectories, timing of risk and protective mechanisms, animal model systems to study mechanisms underlying gene-environment interplay, large-sample genome-envirome designs to address G × E and longitudinal studies to elucidate how rGE plays out over time. Clinical and public health implications are discussed.

Serotonin mediated immunoregulation and neural functions: Complicity in the aetiology of autism spectrum disorders

Serotonergic system has long been implicated in the aetiology of autism spectrum disorders (ASD), since platelet hyperserotonemia is consistently observed in a subset of autistic patients, who respond well to selective serotonin reuptake inhibitors. Apart from being a neurotransmitter, serotonin functions as a neurotrophic factor directing brain development and as an immunoregulator modulating immune responses. Serotonin transporter (SERT) regulates serotonin level in lymphoid tissues to ensure its proper functioning in innate and adaptive responses. Immunological molecules such as cytokines in turn regulate the transcription and activity of SERT. Dysregulation of serotonergic system could trigger signalling cascades that affect normal neural-immune interactions culminating in neurodevelopmental and neural connectivity defects precipitating behavioural abnormalities, or the disease phenotypes. Therefore, we suggest that a better understanding of the cross talk between serotonergic genes, immune systems and serotonergic neurotransmission will open wider avenues to develop pharmacological leads for addressing the core ASD behavioural deficits.

The developmental disruptions of serotonin signaling may involved in autism during early brain development

Autism is a developmental disorder defined by the presence of a triad of communication, social and stereo typical behavioral characteristics with onset before 3years of age. In spite of the fact that there are potential environmental factors for autistic behavior, the dysfunction of serotonin during early development of the brain could be playing a role in this prevalence rise. Serotonin can modulate a number of developmental events, including cell division, neuronal migration, cell differentiation and synaptogenesis. Hyperserotonemia during fetal development results in the loss of serotonin terminals through negative feedback. The increased serotonin causes a decrease of oxytocin in the paraventricular nucleus of the hypothalamus and an increase in calcitonin gene-related peptide (CGRP) in the central nucleus of the amygdale, which are associated with social interactions and vital in autism. However, hyposerotonemia may be also relevant to the development of sensory as well as motor and cognitive faculties. And the paucity of placenta-derived serotonin should have potential importance when the pathogenesis of autism is considered. This review briefly summarized the developmental disruptions of serotonin signaling involved in the pathogenesis of autism during early development of the brain.

The use of central nervous system active drugs during pregnancy

CNS-active drugs are used relatively often during pregnancy. Use during early pregnancy may increase the risk of a congenital malformation; use during the later part of pregnancy may be associated with preterm birth, intrauterine growth disturbances and neonatal morbidity. There is also a possibility that drug exposure can affect brain development with long-term neuropsychological harm as a result. This paper summarizes the literature on such drugs used during pregnancy: opioids, anticonvulsants, drugs used for Parkinson's disease, neuroleptics, sedatives and hypnotics, antidepressants, psychostimulants, and some other CNS-active drugs. In addition to an overview of the literature, data from the Swedish Medical Birth Register (1996-2011) are presented. The exposure data are either based on midwife interviews towards the end of the first trimester or on linkage with a prescribed drug register. An association between malformations and maternal use of anticonvulsants and notably valproic acid is well known from the literature and also demonstrated in the present study. Some other associations between drug exposure and outcome were found.

Association of maternal exposure to childhood abuse with elevated risk for autism in offspring

IMPORTANCE

Adverse perinatal circumstances have been associated with increased risk for autism in offspring. Women exposed to childhood abuse experience more adverse perinatal circumstances than women unexposed, but whether maternal abuse is associated with autism in offspring is unknown.

OBJECTIVES

To determine whether maternal exposure to childhood abuse is associated with risk for autism in offspring and whether possible increased risk is accounted for by a higher prevalence of adverse perinatal circumstances among abused women, including toxemia, low birth weight, gestational diabetes, previous induced abortion, intimate partner abuse, pregnancy length shorter than 37 weeks, selective serotonin reuptake inhibitor use, and alcohol use and smoking during pregnancy.

DESIGN AND SETTING

Nurses' Health Study II, a population-based longitudinal cohort of 116 430 women.

PARTICIPANTS

Nurses with data on maternal childhood abuse and child's autism status (97.0% were of white race/ethnicity). Controls were randomly selected from among children of women who did not report autism in offspring (participants included 451 mothers of children with autism and 52 498 mothers of children without autism).

MAIN OUTCOME MEASURES

Autism spectrum disorder in offspring, assessed by maternal report and validated with the Autism Diagnostic Interview-Revised in a subsample.

RESULTS

Exposure to abuse was associated with increased risk for autism in children in a monotonically increasing fashion. The highest level of abuse was associated with the greatest prevalence of autism (1.8% vs 0.7% among women not abused, P = .005) and with the greatest risk for autism adjusted for demographic factors (risk ratio, 3.7; 95% CI, 2.3-5.8). All adverse perinatal circumstances except low birth weight were more prevalent among women abused in childhood. Adjusted for perinatal factors, the association of maternal childhood abuse with autism in offspring was slightly attenuated (risk ratio for highest level of abuse, 3.0; 95% CI, 1.9-4.8).

CONCLUSIONS AND RELEVANCE

We identify an intergenerational association between maternal exposure to childhood abuse and risk for autism in the subsequent generation. Adverse perinatal circumstances accounted for only a small portion of this increased risk.

Placental serotonin: implications for the developmental effects of SSRIs and maternal depression

In addition to its role in the pathophysiology of numerous psychiatric disorders, increasing evidence points to serotonin (5-HT) as a crucial molecule for the modulation of neurodevelopmental processes. Recent evidence indicates that the placenta is involved in the synthesis of 5-HT from maternally derived tryptophan (TRP). This gives rise to the possibility that genetic and environmental perturbations directly affecting placental TRP metabolism may lead to abnormal brain circuit wiring in the developing embryo, and therefore contribute to the developmental origin of psychiatric disorders. In this review, we discuss how perturbations of the placental TRP metabolic pathway may lead to abnormal brain development and function throughout life. Of particular interest is prenatal exposure to maternal depression and antidepressants, both known to alter fetal development. We review existing evidence on how antidepressants can alter placental physiology in its key function of maintaining fetal homeostasis and have long-term effects on fetal forebrain development.

Placenta-derived hypo-serotonin situations in the developing forebrain cause autism

Autism is a pervasive developmental disorder that is characterized by the behavioral traits of impaired social cognition and communication, and repetitive and/or obsessive behavior and interests. Although there are many theories and speculations about the pathogenetic causes of autism, the disruption of the serotonergic system is one of the most consistent and well-replicated findings. Recently, it has been reported that placenta-derived serotonin is the main source in embryonic day (E) 10-15 mouse forebrain, after that period, the serotonergic fibers start to supply serotonin into the forebrain. E 10-15 is the very important developing period, when cortical neurogenesis, migration and initial axon targeting are processed. Since all these events have been considered to be involved in the pathogenesis of autism and they are highly controlled by serotonin signals, the paucity of placenta-derived serotonin should have potential importance when the pathogenesis of autism is considered. I, thus, postulate a hypothesis that placenta-derived hypo-serotonin situations in the developing forebrain cause autism. The hypothesis is as follows. Various factors, such as inflammation, dysfunction of the placenta, together with genetic predispositions cause a decrease of placenta-derived serotonin levels. The decrease of placenta-derived serotonin levels leads to hypo-serotonergic situations in the forebrain of the fetus. The paucity of serotonin in the forebrain leads to mis-wiring in important regions which are responsible for the theory of mind. The paucity of serotonin in the forebrain also causes over-growth of serotonergic fibers. These disturbances result in network deficiency and aberration of the serotonergic system, leading to the autistic phenotypes.

When the bough breaks: rethinking treatment strategies for perinatal depression

Awareness of depression among OB-GYN physicians has increased with the result that more than 13% of pregnant women in the United States receive prescriptions for antidepressant medications. But the safety and effectiveness of these compounds has been exaggerated while the effectiveness of psychotherapy has been overlooked and distorted and various medical guidelines for treatment of perinatal depression have been downplayed or ignored. This article addresses the common fears and misconceptions surrounding treatment of depression during pregnancy and after childbirth. The effectiveness of strategic cognitive-behavioral therapy enhanced with hypnosis offers excellent results without the risks associated with these medications. Targets for focused intervention are identified and discussed.

Expression of 5HT-related genes after perinatal treatment with 5HT agonists

Serotonin (5HT) is a biologically active amine with diverse roles in the mammalian organism. Developmental alterations in 5HT homeostasis could lead to exposure of the developing brain to non-optimal serotonin concentrations that may result in developmental and behavioral deficits. In order to explore the molecular basis of the effects of developmental disturbances on 5HT metabolism on adult central 5HT homeostasis, observed in our previous studies, we measured changes in gene expression of the neuronal 5HT-regulating proteins in adult animals after perinatal treatment with the immediate 5HT precursor 5-hydroxytryptophan (5HTP, 25 mg/kg), or monoamine oxidase (MAO) inhibitor tranylcypromine (TCP 2 mg/kg), during the period of the most intensive development of 5HT neurons — from gestational day 12 until postnatal day 21. Adult animals were sacrificed and the relative mRNA levels for tryptophan hydroxylase 2, MAO A, MAO B, receptors 5HT1A and 5HT2A, 5HT transporter (5HTT) and vesicular monoamine transporter (VMAT) were determined in the raphe nuclei region and prefrontal cortex using Real-Time Relative qRT-PCR. In comparison to the saline treated animals, treatment with 5HTP caused mild but significant increase in MAO A and MAO B mRNA abundance. TCP-treated animals, besides an increase in mRNA abundance for both MAO genes, displayed significantly increased 5HTT and VMAT2 mRNA levels and significantly decreased 5HT1A receptor mRNA levels. Our results suggest that perinatal exposure of rats to 5HTP, and especially TCP, induces long-lasting/permanent changes in the expression of 5HT-regulating genes, that presumably underlie 5HT-related neurochemical and behavioral changes in adult animals.

An ecological study on childhood autism

BACKGROUND AND METHODS

Idiopathic autism, suspected to be caused by exposure of genetically susceptible individuals to unknown environmental triggers, has increased dramatically in the past 25 years. The objectives of our study were to determine, using a linear regression model, whether the county prevalence of autism in the Pacific Northwest of the United States was associated with the source of drinking water for that county and whether this relationship was dependent on the level of environmental pollutants and meteorological factors in the county.

RESULTS

We found the previously reported relationship between precipitation and autism in a county was dependent on the amount of drinking water derived from surface sources in the county. We also found a positive association between the EPA's risk of neurological disease and autism, but this relationship was only present in warm areas.

CONCLUSIONS

Our study provides evidence for the hypothesis that environmental factors are associated with autism and that meteorological factors play a role in this relationship.

Psychoactive pharmaceuticals induce fish gene expression profiles associated with human idiopathic autism

Idiopathic autism, caused by genetic susceptibility interacting with unknown environmental triggers, has increased dramatically in the past 25 years. Identifying environmental triggers has been difficult due to poorly understood pathophysiology and subjective definitions of autism. The use of antidepressants by pregnant women has been associated with autism. These and other unmetabolized psychoactive pharmaceuticals (UPPs) have also been found in drinking water from surface sources, providing another possible exposure route and raising questions about human health consequences. Here, we examined gene expression patterns of fathead minnows treated with a mixture of three psychoactive pharmaceuticals (fluoxetine, venlafaxine & carbamazepine) in dosages intended to be similar to the highest observed conservative estimates of environmental concentrations. We conducted microarray experiments examining brain tissue of fish exposed to individual pharmaceuticals and a mixture of all three. We used gene-class analysis to test for enrichment of gene sets involved with ten human neurological disorders. Only sets associated with idiopathic autism were unambiguously enriched. We found that UPPs induce autism-like gene expression patterns in fish. Our findings suggest a new potential trigger for idiopathic autism in genetically susceptible individuals involving an overlooked source of environmental contamination.

A lack of association between hyperserotonemia and the increased frequency of serum anti-myelin basic protein auto-antibodies in autistic children

BACKGROUND

One of the most consistent biological findings in autism is the elevated blood serotonin levels. Immune abnormalities, including autoimmunity with production of brain specific auto-antibodies, are also commonly observed in this disorder. Hyperserotonemia may be one of the contributing factors to autoimmunity in some patients with autism through the reduction of T-helper (Th) 1-type cytokines. We are the first to investigate the possible role of hyperserotonemia in the induction of autoimmunity, as indicated by serum anti-myelin-basic protein (anti-MBP) auto-antibodies, in autism.

METHODS

Serum levels of serotonin and anti-MBP auto-antibodies were measured, by ELISA, in 50 autistic patients, aged between 5 and 12 years, and 30 healthy-matched children.

RESULTS

Autistic children had significantly higher serum levels of serotonin and anti-MBP auto-antibodies than healthy children (P < 0.001 and P < 0.001, respectively). Increased serum levels of serotonin and anti-MBP auto-antibodies were found in 92% and 80%, respectively of autistic patients. Patients with severe autism had significantly higher serum serotonin levels than children with mild to moderate autism (P < 0.001). Serum serotonin levels had no significant correlations with serum levels of anti-MBP auto-antibodies in autistic patients (P = 0.39).

CONCLUSIONS

Hyperserotonemia may not be one of the contributing factors to the increased frequency of serum anti-MBP auto-antibodies in some autistic children. These data should be treated with caution until further investigations are performed. However, inclusion of serum serotonin levels as a correlate may be useful in other future immune studies in autism to help unravel the long-standing mystery of hyperserotonemia and its possible role in the pathophysiology of this disorder.

Genetic influences on social cognition

Human social behavior develops under the influence of genetic, environmental, and cultural factors. Social cognition comprises our ability to understand and respond appropriately to other people's social approaches or responses. The concept embraces self-knowledge and theory of mind, or the ability to think about emotions and behavior from the perspective of another person. The neuropeptides oxytocin (OT) and vasopressin (AVP) are now known to play an important role, affecting individual differences in parenting behavior, social recognition, and affiliative behaviors. The processes of social cognition are also supported by reward circuitry, underpinned by the dopaminergic neurotransmitter system. Reward processes build social relationships, in parenting and pair-bonding, and influence social interactions that require trust, or display altruism. The impact of emotional regulation upon social behavior, including mood and anxiety, is also mediated through the serotonergic system. Variation in activity of serotonergic networks in the brain influences emotional responsivity, including subjective feelings, physiological responses, emotional expressions, and the tendency to become engaged in action as a consequence of a feeling state. Genetic variation in the receptors associated with OT, AVP, dopamine, and serotonin has been intensively studied in humans and animal models. Recent findings are building an increasingly coherent picture of regulatory mechanisms.

Neurobehavioral manifestations of developmental impairment of the brain

Individual characteristics of human nature (e.g. introversion, extroversion, mood, activity, adaptability, aggressiveness, social ability, anxiety) do not need to be primarily innate. They can be determined by the action of various influences and their interactions on functional development of the brain. There is ample epidemiological and experimental evidence that chemical and/or physical factors acting during sensitive time windows of the brain development can cause mental, behavioral, emotional and/or cognitive disorders. Environmental pollutants, addictive substances, drugs, malnutrition, excessive stress and/or hypoxia-ischemia were reported to induce functional maldevelopment of the brain with consequent neurobehavioral disorders. The article provides review on most significant neurobehavioral manifestations of developmental impairment of the brain during prenatal, perinatal and early postnatal period. The most known adverse factors causing developmental neurobehavioral dysfunctions in humans as well as in experimental animals are discussed.