Prenatal antidepressant exposure: clinical and preclinical findings

Neonatal Opioid Withdrawal Syndrome Following Prenatal Use of Supplements Containing Tianeptine

Tianeptine is an opioid receptor agonist that is prescribed as an antidepressant in many countries. In the United States, tianeptine is not approved for medical use because of its potential for abuse and addiction. Nonetheless, products containing tianeptine are easily obtainable and are marketed as dietary supplements. There are increasing reports of adverse effects and fatal toxicities resulting from tianeptine use among adolescents and adults. This emerging public health threat could escalate the opioid epidemic and drive increased newborn perinatal exposure. The impact of in utero exposure to tianeptine has not been studied, and to our knowledge, the authors of only 1 report have documented possible neonatal effects. Here, we describe a case of chronic prenatal exposure to tianeptine in the setting of maternal dependence on dietary supplements. This infant developed signs of severe withdrawal shortly after birth that were refractory to treatment with oral phenobarbital but responded to subsequent oral morphine therapy. On further questioning, the mother revealed the use of a tianeptine-containing dietary supplement. We did not perform confirmatory toxicology testing because tianeptine is not assayed by usual urine drug screening tests. For infants with clinical signs of opioid withdrawal without known etiology, we suggest that the maternal interview should inquire about the use of neurotropic over-the-counter drugs.

Perinatal exposure to fluoxetine and maternal adversity affect myelin-related gene expression and epigenetic regulation in the corticolimbic circuit of juvenile rats

Many pregnant women experience symptoms of depression, and are often treated with selective serotonin reuptake inhibitor (SSRI) antidepressants, such as fluoxetine. In utero exposure to SSRIs and maternal depressive symptoms is associated with sex-specific effects on the brain and behavior. However, knowledge about the neurobiological mechanisms underlying these sex differences is limited. In addition, most animal research into developmental SSRI exposure neglects the influence of maternal adversity. Therefore, we used a rat model relevant to depression to investigate the molecular effects of perinatal fluoxetine exposure in male and female juvenile offspring. We performed RNA sequencing and targeted DNA methylation analyses on the prefrontal cortex and basolateral amygdala; key regions of the corticolimbic circuit. Perinatal fluoxetine enhanced myelin-related gene expression in the prefrontal cortex, while inhibiting it in the basolateral amygdala. SSRI exposure and maternal adversity interacted to affect expression of genes such as myelin-associated glycoprotein (Mag) and myelin basic protein (Mbp). We speculate that altered myelination reflects altered brain maturation. In addition, these effects are stronger in males than in females, resembling known behavioral outcomes. Finally, Mag and Mbp expression correlated with DNA methylation, highlighting epigenetic regulation as a potential mechanism for developmental fluoxetine-induced changes in myelination.

Interactions between maternal fluoxetine exposure, the maternal gut microbiome and fetal neurodevelopment in mice

Selective serotonin reuptake inhibitors (SSRIs) are the most widely used treatment by women experiencing depression during pregnancy. However, the effects of maternal SSRI use on early offspring development remain poorly understood. Recent studies suggest that SSRIs can modify the gut microbiota and interact directly with particular gut bacteria, raising the question of whether the gut microbiome impacts host responses to SSRIs. In this study, we investigate effects of prenatal SSRI exposure on fetal neurodevelopment and further evaluate potential modulatory influences of the maternal gut microbiome. We demonstrate that maternal treatment with the SSRI fluoxetine induces widespread alterations in the fetal brain transcriptome during midgestation, including increases in the expression of genes relevant to synaptic organization and neuronal signaling and decreases in the expression of genes related to DNA replication and mitosis. Notably, maternal fluoxetine treatment from E7.5 to E14.5 has no overt effects on the composition of the maternal gut microbiota. However, maternal pretreatment with antibiotics to deplete the gut microbiome substantially modifies transcriptional responses of the fetal brain to maternal fluoxetine treatment. In particular, maternal fluoxetine treatment elevates localized expression of the opioid binding protein/cell adhesion molecule like gene Opcml in the fetal thalamus and lateral ganglionic eminence, which is prevented by maternal antibiotic treatment. Together, these findings reveal that maternal fluoxetine treatment alters gene expression in the fetal brain through pathways that are impacted, at least in part, by the presence of the maternal gut microbiota.

Fetal teratogenicity in a rhesus macaque (Macaca mulatta): Association with the chronic maternal treatment of amitriptyline

Amitriptyline is a tricyclic antidepressant commonly prescribed in humans for pain and sleep disorders and in non-human primates for self-injurious behaviors. Here, we report a clinical case on the teratogenic effect of maternal-fetal amitriptyline exposure.

Imipramine and Venlafaxine Differentially Affect Primary Glial Cultures of Prenatally Stressed Rats

Here, we examine the effects of prenatal administration of two antidepressants—imipramine (IMI) and venlafaxine (VEN)—on morphology and activity of a primary glial culture. Microglia are targeted by antidepressants used for antenatal depression and are important regulators of central nervous system development. In this study, female Wistar rats were assigned to one of four groups: a control group that received water ad libitum (1), and groups that received additionally once daily either water (2), IMI (10 mg/kg) (3), or VEN (20 mg/kg) (4) by oral gavage from gestation day 7 to 22. Oral gavage administration induced prenatal stress. Cell cultures were obtained from the brains of 1-day-old pups. Prenatal stress caused a disturbance of sensorimotor function in pups. Prenatal stress also produced alterations in the glial cultures, specifically, an increased percentage of microglia in the mixed glial cultures and an increased percentage of dead cells. Moreover, increased levels of IL1-β, TNF-α, NO, and an increased expression of CX3CR1 mRNA were found in microglia. However, the ratio of Bax/Bcl2 mRNA was reduced. Prenatal stress increased the vulnerability of microglia to lipopolysaccharide (LPS). The mixed glial culture derived from pups exposed to IMI showed greater morphological changes and the highest percentage of microglia. Microglia were characterized by the largest increase in the production of pro-inflammatory cytokines and NO, and the greatest reduction in the expression of CX3CR1 mRNA. Exposure to IMI reduced the effects of LPS on IL-1β production and Bax/Bcl2 mRNA, and exacerbated the effects of LPS on CX3CR1 mRNA expression. Prenatal administration of VEN induced protective effects on microglia, as measured by all studied parameters. Taken together, our data suggest that, by disturbing microglia function, exposure to even mild forms of chronic prenatal stress may predispose individuals to psychiatric or neurodevelopmental disorders. These data also indicate that chronic mild stress sensitizes microglia to immune challenges, which may lead to enhanced neuronal damage in the embryonic brain. The observed detrimental effects of IMI on microglial activity under conditions of prenatal stress may help to explain the teratogenic effects of IMI reported in the literature.

Early vocal contact and music in the NICU: new insights into preventive interventions

It is now clearly established that the environment and the sensory stimuli, particularly during the perinatal period, have an impact on infant's development. During the last trimester of gestation, activity-dependent plasticity shapes the fetal brain, and prematurity has been shown to alter the typical developmental trajectories. In this delicate period, preventive interventions aiming at modulating these developmental trajectories through activity-inducing interventions are currently underway to be tested. The purpose of this review paper is to describe the potentialities of early vocal contact and music on the preterm infant's brain development, and their potential beneficial effect on early development. Scientific evidence supports a behavioral orientation of the newborn to organized sounds, such as those of voice and music, and recent neuroimaging studies further confirm full cerebral processing of music as multisensory stimuli. However, the impact of long-term effects of music exposure and early vocal contact on preterm infants' long-term neurodevelopment needs be further investigated. To conclude, it is necessary to establish the neuroscientific bases of the early perception and the long-term effects of music and early vocal contact on the premature newborns' development. Scientific projects are currently on the way to fill this gap in knowledge.

Use of Prescribed Psychotropics during Pregnancy: A Systematic Review of Pregnancy, Neonatal, and Childhood Outcomes

This paper reviews the findings from preclinical animal and human clinical research investigating maternal/fetal, neonatal, and child neurodevelopmental outcomes following prenatal exposure to psychotropic drugs. Evidence for the risks associated with prenatal exposure was examined, including teratogenicity, neurodevelopmental effects, neonatal toxicity, and long-term neurobehavioral consequences (i.e., behavioral teratogenicity). We conducted a comprehensive review of the recent results and conclusions of original research and reviews, respectively, which have investigated the short- and long-term impact of drugs commonly prescribed to pregnant women for psychological disorders, including mood, anxiety, and sleep disorders. Because mental illness in the mother is not a benign event, and may itself pose significant risks to both mother and child, simply discontinuing or avoiding medication use during pregnancy may not be possible. Therefore, prenatal exposure to psychotropic drugs is a major public health concern. Decisions regarding drug choice, dose, and duration should be made carefully, by balancing severity, chronicity, and co-morbidity of the mental illness, disorder, or condition against the potential risk for adverse outcomes due to drug exposure. Globally, maternal mental health problems are considered as a major public health challenge, which requires a stronger focus on mental health services that will benefit both mother and child. More preclinical and clinical research is needed in order to make well-informed decisions, understanding the risks associated with the use of psychotropic medications during pregnancy.

Risk of adverse perinatal outcomes among women with pharmacologically treated and untreated depression during pregnancy: A retrospective cohort study

BACKGROUND

The association between antidepressant use during pregnancy and adverse perinatal outcomes is unclear. The association without taking into consideration the independent effect of depression leads to a confounding of the effects of antidepressants with those of the underlying reason for the use of those medications. Additionally, a history of depression and antidepressant use may also influence this association.

OBJECTIVE

This study examined the risks of adverse perinatal outcomes associated with antidepressant use during pregnancy.

METHODS

This retrospective cohort study used population-based data in Alberta, Canada, for women who delivered between 2012 and 2015 (n = 158486). Women with depression were identified using a validated case definition, and the receipt of antidepressants was identified using Anatomical Therapeutic Chemical codes. Adverse perinatal outcomes such as severe maternal/neonatal morbidity, preterm birth, and neonatal intensive care unit admission were assessed. Multivariable log-binomial regression was used to estimate the risk of adverse perinatal outcomes associated with antidepressants, adjusting for age and parity.

RESULTS

In total, 9.1% women had depression and 2.5% women received antidepressants during pregnancy. The relative risk of severe neonatal morbidity/mortality was 1.25 (95% confidence interval 1.17, 1.33) times higher for women with depression alone compared to women without depression. The risk of severe neonatal morbidity/mortality was 1.51 (95% confidence interval 1.36, 1.66) times higher for women who used antidepressants compared to women with depression alone-however, the risk differed between the women with and without a history of antidepressant use. A similar risk pattern was observed for preterm birth and neonatal intensive care unit admission.

CONCLUSIONS

Both depression and antidepressant use were independently associated with the risk of adverse perinatal outcomes; however, the risk associated with antidepressants was higher over and above the risk associated with depression. This may reflect the biological effects of antidepressants, greater severity of depression in those treated, or both.

In Utero Exposure to Citalopram Mitigates Maternal Stress Effects on Fetal Brain Development

Human epidemiological and animal-model studies suggest that separate exposure to stress or serotonin-selective reuptake inhibitor (SSRI) antidepressants during pregnancy increases risks for neurodevelopmental disorders in offspring. Yet, little is known about the combined effects of maternal stress and SSRIs with regard to brain development in utero. We found that the placenta is highly permeable to the commonly prescribed SSRI (±)-citalopram (CIT) in humans and mice, allowing rapid exposure of the fetal brain to this drug. We investigated the effects of maternal chronic unpredictable stress in mice with or without maternal oral administration of CIT from embryonic day (E)8 to E17. We assessed fetal brain development using magnetic resonance imaging and quantified changes in serotonergic, thalamocortical, and cortical development. In utero exposure to maternal stress did not affect overall fetal brain growth. However, serotonin tissue content in the fetal forebrain was increased in association with maternal stress; this increase was reversed by maternal CIT. In utero exposure to stress increased the numbers of deep-layer neurons in specific cortical regions, whereas CIT increased overall cell numbers without changing the proportions of layer-specific neurons to offset the effects of stress on deep-layer cortical development. These findings suggest that stress and SSRI exposure in utero differentially impact serotonin-dependent fetal neurodevelopment such that CIT reverses key effects of maternal gestational stress on offspring brain development.

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.

Prenatal and early postnatal measures of brain development and childhood sleep patterns

BackgroundBrain development underlies maturation of sleep patterns throughout childhood. Intrauterine head growth-marker of early neurodevelopment-has not been associated with childhood sleep characteristics. We explored associations between ultrasonographic measures of prenatal and early postnatal neurodevelopment and childhood sleep.MethodsA total of 6,808 children from a population-based birth cohort (Generation R) were included. Head circumference (HC) and lateral ventricles size were assessed with mid- and late-pregnancy fetal ultrasounds, and with cranial ultrasound 3-20 weeks postnatally. Mothers reported children's sleep duration at 2 and 3 years, and sleep problems at 1.5, 3, and 6 years.ResultsLarger ventricular size, but not HC, was related to longer sleep duration at 3 years (β=0.06 h, 95% confidence interval (CI): 0.02; 0.10 in late-pregnancy and β=0.11 h, 95% CI: 0.02; 0.20 in early infancy, mid-pregnancy parameters were unrelated to sleep duration). Larger HC in mid-pregnancy was associated with a reduced risk for being a "problematic sleeper" up to the age of 6 years (odds ratio (OR): 0.94, 95% CI: 0.89; 0.99). Consistently, children with larger HC in early infancy were less likely to be "problematic sleepers" at 3 and 6 years.ConclusionsThis study shows that variations in fetal and neonatal brain size may underlie behavioral expression of sleep in childhood. Albeit small effect estimates, these associations provide evidence for neurodevelopmental origins of sleep.

A systematic review of maternal antidepressant use in pregnancy and short- and long-term offspring's outcomes

The relative safety of antidepressants during pregnancy has received substantial attention, but most syntheses fail to account for mental illness effects. We aimed to evaluate the literature comparing low birth weight (LBW) and neurodevelopmental and neurobehavioural outcomes for children whose mothers took antidepressants in pregnancy compared to those whose mothers had common mental disorders, or symptoms, but who did not take antidepressants during pregnancy. A systematic review was conducted searching PubMed, MEDLINE, PsycINFO and Embase in January 2015. A modified version of the Newcastle Ottawa Scale was used to assess study quality. Eleven cohort studies were included: four reporting a LBW outcome (all with higher risk of bias) and seven reporting a neurodevelopmental outcome (five with higher risk of bias). We found only limited evidence of gestational age-adjusted LBW in exposed children in two studies which had a higher risk of bias and did not control for depressive symptom severity. Only five (7.5%) neurodevelopmental outcomes and one (12.5%) neurobehavioural outcome showed evidence of a statistically significant effect, three out of four were from studies with a higher risk of bias. There is little robust evidence indicating a detrimental effect of antidepressant use during pregnancy on LBW and neurodevelopmental and neurobehavioural outcomes. More rigorous study designs are needed.

Rethinking psychopharmacotherapy: The role of treatment context and brain plasticity in antidepressant and antipsychotic interventions

Emerging evidence indicates that treatment context profoundly affects psychopharmacological interventions. We review the evidence for the interaction between drug application and the context in which the drug is given both in human and animal research. We found evidence for this interaction in the placebo response in clinical trials, in our evolving knowledge of pharmacological and environmental effects on neural plasticity, and in animal studies analyzing environmental influences on psychotropic drug effects. Experimental placebo research has revealed neurobiological trajectories of mechanisms such as patients' treatment expectations and prior treatment experiences. Animal research confirmed that "enriched environments" support positive drug effects, while unfavorable environments (low sensory stimulation, low rates of social contacts) can even reverse the intended treatment outcome. Finally we provide recommendations for context conditions under which psychotropic drugs should be applied. Drug action should be steered by positive expectations, physical activity, and helpful social and physical environmental stimulation. Future drug trials should focus on fully controlling and optimizing such drug×environment interactions to improve trial sensitivity and treatment outcome.

Prenatal stress, regardless of concurrent escitalopram treatment, alters behavior and amygdala gene expression of adolescent female rats

Depression during pregnancy has been linked to in utero stress and is associated with long-lasting symptoms in offspring, including anxiety, helplessness, attentional deficits, and social withdrawal. Depression is diagnosed in 10-20% of expectant mothers, but the impact of antidepressant treatment on offspring development is not well documented, particularly for females. Here, we used a prenatal stress model of maternal depression to test the hypothesis that in utero antidepressant treatment could mitigate the effects of prenatal stress. We also investigated the effects of prenatal stress and antidepressant treatment on gene expression related to GABAergic and serotonergic neurotransmission in the amygdala, which may underlie behavioral effects of prenatal stress. Nulliparous female rats were implanted with osmotic minipumps delivering clinically-relevant concentrations of escitalopram and mated. Pregnant dams were exposed to 12 days of mixed-modality stressors, and offspring were behaviorally assessed in adolescence (postnatal day 28) and adulthood (beyond day 90) to determine the extent of behavioral change. We found that in utero stress exposure, regardless of escitalopram treatment, increased anxiety-like behavior in adolescent females and profoundly influenced amygdala expression of the chloride transporters KCC2 and NKCC1, which regulate GABAergic function. In contrast, prenatal escitalopram exposure alone elevated amygdala expression of 5-HT1A receptors. In adulthood, anxiety-like behavior returned to baseline and gene expression effects in the amygdala abated, whereas deficits emerged in novel object recognition for rats exposed to stress during gestation. These findings suggest prenatal stress causes age-dependent deficits in anxiety-like behavior and amygdala function in female offspring, regardless of antidepressant exposure.

Cell-Based High-Throughput Screening for Aromatase Inhibitors in the Tox21 10K Library

Multiple mechanisms exist for endocrine disruption; one nonreceptor-mediated mechanism is via effects on aromatase, an enzyme critical for maintaining the normal in vivo balance of androgens and estrogens. We adapted the AroER tri-screen 96-well assay to 1536-well format to identify potential aromatase inhibitors (AIs) in the U.S. Tox21 10K compound library. In this assay, screening with compound alone identifies estrogen receptor alpha (ERα) agonists, screening in the presence of testosterone (T) identifies AIs and/or ERα antagonists, and screening in the presence of 17β-estradiol (E2) identifies ERα antagonists. Screening the Tox-21 library in the presence of T resulted in finding 302 potential AIs. These compounds, along with 31 known AI actives and inactives, were rescreened using all 3 assay formats. Of the 333 compounds tested, 113 (34%; 63 actives, 50 marginal actives) were considered to be potential AIs independent of cytotoxicity and ER antagonism activity. Structure-activity analysis suggested the presence of both conventional (eg, 1, 2, 4, - triazole class) and novel AI structures. Due to their novel structures, 14 of the 63 potential AI actives, including both drugs and fungicides, were selected for confirmation in the biochemical tritiated water-release aromatase assay. Ten compounds were active in the assay; the remaining 4 were only active in high-throughput screen assay, but with low efficacy. To further characterize these 10 novel AIs, we investigated their binding characteristics. The AroER tri-screen, in high-throughput format, accurately and efficiently identified chemicals in a large and diverse chemical library that selectively interact with aromatase.

The effects of antenatal depression and antidepressant treatment on placental gene expression

The effects of antenatal depression and antidepressant treatment during pregnancy on both mother and child are vigorously studied, but the underlying biology for these effects is largely unknown. The placenta plays a crucial role in the growth and development of the fetus. We performed a gene expression study on the fetal side of the placenta to investigate gene expression patterns in mothers with antenatal depression and in mothers using antidepressant treatment during pregnancy. Placental samples from mothers with normal pregnancies, from mothers with antenatal depression, and from mothers using antidepressants were collected. We performed a pilot microarray study to investigate alterations in the gene expression and selected several genes from the microarray for biological validation with qPCR in a larger sample. In mothers with antenatal depression 108 genes were differentially expressed, whereas 109 genes were differentially expressed in those using antidepressants. Validation of the microarray revealed more robust gene expression differences in the seven genes picked for confirmation in antidepressant-treated women than in depressed women. Among the genes that were validated ROCK2 and C12orf39 were differentially expressed in both depressed and antidepressant-treated women, whereas ROCK1, GCC2, KTN1, and DNM1L were only differentially expressed in the antidepressant-treated women. In conclusion, antenatal depression and antidepressant exposure during pregnancy are associated with altered gene expression in the placenta. Findings on those genes picked for validation were more robust among antidepressant-treated women than in depressed women, possibly due to the fact that depression is a multifactorial condition with varying degrees of endocrine disruption. It remains to be established whether the alterations found in the gene expression of the placenta are found in the fetus as well.

Antenatal depression and antidepressants during pregnancy: unraveling the complex interactions for the offspring

During pregnancy the risk for a woman to develop a depressive episode is as high as 20%. Antenatal depression is not harmless for the developing child as several changes, including neurodevelopmental alterations, have been reported. Sometimes it is unavoidable to treat a pregnant mother with antidepressants, especially when she is suicidal. Currently, selective serotonin reuptake inhibitors (SSRIs) are the pharmacological choice of antidepressant treatment. SSRIs do not cause gross teratogenic alterations and are generally considered safe for use in pregnancy. However, although SSRIs may relieve the maternal symptoms, they definitively cross the placenta partially influencing the neurodevelopment of the fetus. In this review an overview is given of the effects on the offspring of maternal antenatal depression and the putative neurodevelopmental effects of SSRI treatment during pregnancy. Although we primarily focus on human data, some animal data are discussed to describe possible mechanisms on how SSRIs are affecting underlying biological mechanisms associated with depression. In summary, maternal depression may have long-lasting effects on the offspring, whereas prenatal SSRI exposure also increases the risk for long-lasting effects. It remains to be determined whether the effects found after SSRI treatment in pregnant women are only due to the SSRI exposure or if the underlying depression is also contributing to these effects. The possibility of epigenetic alterations as one of the underlying mechanisms that is altered by SSRI exposure is discussed. However much more research in this area is needed to explain the exact role of epigenetic mechanisms in SSRI exposure during pregnancy.