Ursula Brain

Prenatal Exposure to Maternal Depressed Mood and the MTHFR C677T Variant Affect SLC6A4 Methylation in Infants at Birth

Background Prenatal and early postnatal exposure to maternal depression may “program” childhood behavior via epigenetic processes such as DNA methylation. Methylenetetrahydro-folate reductase (MTHFR) is an important enzyme in the generation of methyl groups for DNA methylation. The common MTHFR C677T variant is associated with depression in men and non-pregnant women, and with global changes in DNA methylation. This study investigated the effect of maternal MTHFR C677T genotype on antenatal maternal mood, and their impact on the gene-specific methylation in pregnant women and their newborn infants. The methylation status of SLC6A4, which encodes the transmembrane serotonin transporter, and BDNF, which encodes brain derived neurotrophic factor, were assessed because of their potential role in behaviour. Methods/Principal Findings Depressed mood was assessed by the Edinburgh Postnatal Depression Scale (EPDS) and the Hamilton Rating Scale for Depression (HAM-D) in women (n = 82, all taking folate) during the 2nd and 3rd trimesters of pregnancy. The methylation status of SLC6A4 and BDNF were assessed in 3rd trimester maternal peripheral leukocytes and in umbilical cord leukocytes collected from their infants at birth. Women with the MTHFR 677TT genotype had greater 2nd trimester depressed mood (p<0.05). Increased 2nd trimester maternal depressed mood (EPDS scores) was associated with decreased maternal and infant SLC6A4 promoter methylation (p<0.05), but had no effect on BDNF promoter methylation. Conclusions These findings show that the MTHFR C677T variant is associated with greater depressed mood during pregnancy. We further showed that prenatal exposure to maternal depressed mood affects gene-specific DNA methylation patterns. These findings support the concept that alterations in epigenetic processes may contribute to developmental programming of behaviour by maternal depression.

Prenatal effects of selective serotonin reuptake inhibitor antidepressants, serotonin transporter promoter genotype (SLC6A4), and maternal mood on child behavior at 3 years of age.

OBJECTIVES To investigate whether prenatal selective serotonin reuptake inhibitor (SSRI) antidepressant exposure affects behavior in 3-year-olds of antenatally anxious or depressed mothers and whether risk was moderated by the serotonin transporter promoter (SLC6A4) genotype. DESIGN Prospective longitudinal cohort design. SETTING Vancouver. PARTICIPANTS Mothers and their 3-year-old children (n = 33 SSRI exposed and n = 42 nonexposed). Main Exposures Prenatal exposure to SSRI antidepressants and prenatal and postnatal maternal mood disturbances. MAIN OUTCOME MEASURES Parent report of child behavior (Child Behavior Checklist, ages 1.5-5 years) and the child SLC6A4 genotype. The covariates used were maternal mood during the third trimester, 3 months postpartum, and at the 3-year follow-up study and the childs 5-minute Apgar score. RESULTS Prenatal exposure to both maternal depressed mood and SSRI antidepressants were associated with increased internalizing behaviors during early childhood, whereas current maternal mood increased risk for externalizing behaviors. Increased child anxiety and depression symptoms were predicted by higher third-trimester maternal anxiety only in children with 2 short S alleles. In contrast, increased aggression and externalizing behaviors were predicted by third-trimester maternal anxiety only in children with 2 copies of the L allele. CONCLUSIONS Exposure to prenatal SSRIs and maternal mood had distinct effects on child behavior at 3 years of age, reflected in an increased level of internalizing behaviors. The impact of antenatal maternal anxiety on child mood was moderated by the child SLC6A4 genotype. Despite SSRI treatment for prenatal maternal mood disturbances, childhood behavior at 3 years of age remained at risk.

Infant developmental outcomes following prenatal exposure to antidepressants, and maternal depressed mood and positive affect

BACKGROUND Prenatal exposure to serotonin reuptake inhibitor (SRI) antidepressants has been associated with delays in early developmental milestones, but there remains uncertainty. Even among a subset of studies examining the Bayley Scales of Infant Development (BSID), some have reported normal mental and psychomotor development while others have suggested a delay in motor development. Given an increasing number of infants exposed to SRIs, furthering our understanding of the possible developmental implications of SRI exposure in utero is critical. AIMS To examine the effects of prenatal serotonin reuptake inhibitor exposure and maternal mood on infant developmental outcomes at 10months of age. STUDY DESIGN Prospective study of mothers and their 10-month-old infants. SUBJECTS We examined 31 mother-child pairs exposed prenatally to SRIs and 52 mother-child pairs who were nonexposed. OUTCOME MEASURE The Bayley Scales of Infant Development (third edition) scores. RESULTS Infants exposed prenatally to SRIs scored significantly lower than nonexposed infants on gross motor (P=0.03), social-emotional (P=0.04) and adaptive behavior (P=0.05) subscales of the BSID-III, controlling for pre- and postnatal maternal depressed mood, smoking and alcohol use during pregnancy. No significant differences in any of the BSID-III subscales were observed between infants exposed and infants nonexposed to pre and postnatal maternal depressed mood (P>0.05). Increased levels of maternal positive affect at 10 months predicted increased social-emotional scores (P=0.03). CONCLUSIONS Infants prenatally exposed to SRIs score significantly lower on the gross motor, social-emotional and adaptive behavior subscales of the BSID-III, and this was not explained by underlying maternal depression.

Neonatal S100B protein levels after prenatal exposure to selective serotonin reuptake inhibitors.

OBJECTIVE: This study investigated neonatal S100B levels as a biomarker of prenatal selective serotonin reuptake inhibitor (SSRI) exposure. METHODS: Maternal (delivery; N = 53) and neonatal (cord; N = 52) serum S100B levels were compared between prenatally SSRI-exposed (maternal, N = 36; neonatal, N = 37; duration: 230 ± 71 days) and nonexposed (maternal, N = 17; neonatal, N = 15) groups. Measures of maternal depression and anxiety symptoms were assessed during the third trimester (33–36 weeks), and neonatal outcomes, including Apgar scores, birth weight, gestational age at birth, and symptoms of poor neonatal adaptation, were recorded. RESULTS: S100B levels were significantly lower in prenatally SSRI-exposed neonates than in nonexposed neonates, controlling for gestational age and third-trimester maternal mood (P = .036). In contrast, SSRI-exposed mothers had significantly higher maternal serum S100B levels, compared with nonexposed mothers (P = .014), even controlling for maternal mood in the third trimester. S100B levels were not associated with maternal or neonatal drug levels, duration of prenatal exposure, demographic variables, or risk for poor neonatal adaptation. CONCLUSIONS: Prenatal SSRI exposure was associated with decreased neonatal serum S100B levels, controlling for prenatal maternal mood. Neonatal S100B levels did not reflect neonatal behavioral outcomes and were not related to pharmacologic indices. These findings are consistent with prenatal alcohol and cocaine exposures, which also alter central serotonin levels.

Prenatal SSRI exposure alters neonatal corticosteroid binding globulin, infant cortisol levels, and emerging HPA function.

BACKGROUND Serotonin influences the development of the hypothalamic-pituitary-adrenal (HPA) system; therefore prenatal exposure to selective serotonin reuptake inhibitor antidepressants (SSRIs) may alter HPA axis development and function. To address this, prenatal exposure to SSRIs and maternal mood were examined in relation to neonatal and infant levels of cortisol and its binding protein, corticosteroid-binding globulin (CBG). METHODS Serum cortisol and CBG levels were assayed from SSRI-exposed and non-exposed mothers and their neonates at delivery. Maternal mood symptoms were documented at 36 weeks gestation. To determine the long-term implications of changes in CBG, levels of salivary cortisol were assessed in infants at 3 months of age. RESULTS Prenatal SSRI exposure significantly increased serum CBG levels in neonates after vaginal delivery (p ≤ 0.038), even when controlling for maternal depression. Neonatal serum cortisol levels did not vary with SSRI exposure or antenatal maternal mood, but were significantly higher following vaginal delivery (p ≤ 0.003). Neonatal serum CBG levels were associated with infant salivary levels of evening cortisol (p ≤ 0.051). In SSRI-exposed infants, increased levels of neonatal CBG predicted a smaller diurnal change in infant salivary cortisol (p ≤ 0.028), regardless of maternal depression. CONCLUSIONS Prenatal SSRI exposure affects the developing HPA system by altering serum CBG levels in neonates and infant salivary cortisol levels. Further research is warranted on the long-term functional implications of the effect of prenatal SSRI exposure on fetal hepatic CBG gene expression and the developing HPA system.

Prenatal serotonin reuptake inhibitor (SRI) antidepressant exposure and serotonin transporter promoter genotype (SLC6A4) influence executive functions at 6 years of age

Prenatal exposure to serotonin reuptake inhibitor (SRI) antidepressants and maternal depression may affect prefrontal cognitive skills (executive functions; EFs) including self-control, working memory and cognitive flexibility. We examined long-term effects of prenatal SRI exposure on EFs to determine whether effects are moderated by maternal mood and/or genetic variations in SLC6A4 (a gene that codes for the serotonin transporter [5-HTT] central to the regulation of synaptic serotonin levels and behavior). Children who were exposed to SRIs prenatally (SRI-exposed N = 26) and non-exposed (N = 38) were studied at age 6 years (M = 6.3; SD = 0.5) using the Hearts & Flowers task (H&F) to assess EFs. Maternal mood was measured during pregnancy (3rd trimester) and when the child was age 6 years (Hamilton Depression Scale). Parent reports of child behavior were also obtained (MacArthur Health & Behavior Questionnaire). Parents of prenatally SRI-exposed children reported fewer child externalizing and inattentive (ADHD) behaviors. Generalized estimate equation modeling showed a significant 3-way interaction between prenatal SRI exposure, SLC6A4 variant, and maternal mood at the 6-year time-point on H&F accuracy. For prenatally SRI-exposed children, regardless of maternal mood, the H&F accuracy of children with reduced 5HTT expression (a short [S] allele) remained stable. Even with increasing maternal depressive symptoms (though all below clinical threshold), EFs of children with at least one short allele were comparable to children with the same genotype whose mothers reported few if any depressive symptoms—in this sense they showed resilience. Children with two long (L) alleles were more sensitive to context. When their mothers had few depressive symptoms, LL children showed extremely good EF performance—better than any other group. When their mothers reported more depressive symptoms, LL childrens EF performance was worse than that of any other group. In the face of a mother with a more depressed mood, EFs were best preserved in children prenatally exposed to SRIs and with at least one short SLC6A4 allele. Yet, prenatally-exposed LL children hold out promise of possibly superior EF if their mothers mood remains euthymic or improves.

Prenatal exposure to serotonin reuptake inhibitor antidepressants and childhood behavior

Background:Animal research has suggested that prenatal serotonin reuptake inhibitor (SRI) antidepressant exposure causes increased anxiety-like behaviors in adulthood. We examined whether in utero SRI exposure influenced externalizing and internalizing behaviors in children at 3 y and again at 6 y of age.Methods:We recruited women in their second trimester of pregnancy from primary maternity care providers in Vancouver British Columbia, Canada. We compared the internalizing, externalizing, and the anxious and attention subscales of the internalizing behaviors scores of children exposed to SRIs and children not exposed to SRIs at age 3 and age 6.Results:We included 110 mother-child pairs (44 exposed to SRI and 66 not exposed). Higher levels of internalizing and anxious behaviors were reported in SRI exposed children at both 3 and 6 y of age compared with children who were not exposed (F = 7.52, P = 0.0072 and F = 7.91, P = 0.0058, respectively). The fully adjusted hierarchical regression models indicated a positive and significant relationship between SRI exposure and increased internalizing and anxious behaviors even when controlling for maternal mood during pregnancy, postpartum and childhood.Conclusion:SRI exposure was associated with sustained higher levels of internalizing behaviors in early childhood even when controlling for maternal depression.

Third Trimester Fetal Heart Rate and Doppler Middle Cerebral Artery Blood Flow Velocity Characteristics During Prenatal Selective Serotonin Reuptake Inhibitor Exposure

Prenatal selective serotonin reuptake inhibitor (SSRI) exposure increases the risk for adverse neonatal behavioral outcomes; although it is unknown whether altered brain function is present before birth. We investigated fetal vascular and heart rate changes at 36-wk gestation in SSRI-treated women with mood disorders (n = 29) [exposed (EXP)] and controls (n = 45) [non-EXP (NEXP)]. Fetal middle cerebral artery (MCA) flow parameters and heart rate characteristics were obtained during pre-SSRI dose morning and postdose afternoon sessions. Maternal mood and cord Hb and hematocrit were measured. Basal fetal heart rate (fHR) did not differ between groups or across the day. The fHR short- and long-term variations, accelerations, and duration of high variability episodes remained lower and did not change across the day in EXP, whereas all increased significantly in NEXP. In both groups, MCA flow velocity and volume flow increased significantly across the day. EXP MCA pulsatility index was significantly lower, as was MCA cross-sectional area. EXP cord Hb and hematocrit were significantly increased. Prenatal SSRI exposure reduced fetal MCA flow resistance and fHR variability, before and after an SSRI dose, controlling for maternal mood. These changes and the SSRI-related increased red cell indices suggest possible fetal hypoxia.

Prenatal antidepressant exposure associated with CYP2E1 DNA methylation change in neonates

Some but not all neonates are affected by prenatal exposure to serotonin reuptake inhibitor antidepressants (SRI) and maternal mood disturbances. Distinguishing the impact of these 2 exposures is challenging and raises critical questions about whether pharmacological, genetic, or epigenetic factors can explain the spectrum of reported outcomes. Using unbiased DNA methylation array measurements followed by a detailed candidate gene approach, we examined whether prenatal SRI exposure was associated with neonatal DNA methylation changes and whether such changes were associated with differences in birth outcomes. Prenatal SRI exposure was first associated with increased DNA methylation status primarily at CYP2E1(βNon-exposed = 0.06, βSRI-exposed = 0.30, FDR = 0); however, this finding could not be distinguished from the potential impact of prenatal maternal depressed mood. Then, using pyrosequencing of CYP2E1 regulatory regions in an expanded cohort, higher DNA methylation status—both the mean across 16 CpG sites (P < 0.01) and at each specific CpG site (P < 0.05)—was associated with exposure to lower 3rd trimester maternal depressed mood symptoms only in the SRI-exposed neonates, indicating a maternal mood x SRI exposure interaction. In addition, higher DNA methylation levels at CpG2 (P = 0.04), CpG9 (P = 0.04) and CpG10 (P = 0.02), in the interrogated CYP2E1 region, were associated with increased birth weight independently of prenatal maternal mood, SRI drug exposure, or gestational age at birth. Prenatal SRI antidepressant exposure and maternal depressed mood were associated with altered neonatal CYP2E1 DNA methylation status, which, in turn, appeared to be associated with birth weight.

Third trimester fetal pulmonary artery Doppler blood flow velocity characteristics following prenatal selective serotonin reuptake inhibitor (SSRI) exposure.

BACKGROUND There have been contradictory reports on the risks of persistent pulmonary hypertension (PPHN) in infants exposed to SSRIs in utero. However, there has been no assessment of fetal pulmonary arterial dynamics in such pregnancies. AIMS AND SUBJECTS: To measure fetal right pulmonary artery (RPA) variables using Doppler ultrasound at 36 weeks gestation in fetuses of mothers taking SSRI antidepressants (n=23) and in a control, normal pregnancy group (n=35). OUTCOME MEASURES At 36 weeks gestation, Doppler ultrasound estimates of Pulsatility Index (PI), Resistance Index (RI), vessel diameter, peak systolic velocity, mean velocity and volume flow were obtained from the fetal right pulmonary artery in a morning session (~0830), before the SSRI mothers took their daily drug dose and in an afternoon session (~1300). Venous blood was drawn at 5 time points across the day (~08:30AM, ~10:30AM, ~13:00PM, ~13:45PM, and ~15:00PM) from the SSRI treated mothers for measurement of plasma SSRI concentration using high performance liquid chromatography tandem mass spectrometry. RESULTS There were no differences in the RPA Doppler measures between the control and SSRI-exposed fetuses. However 8 of the 23 latter fetuses experience transient respiratory difficulties at birth and, in these RPA flow was significantly higher than in the SSR-exposed fetuses without respiratory problems. There were, however, no differences in RPA PI and RI between the 2 groups. CONCLUSIONS In SSRI-exposed infants with transient postnatal respiratory difficulties, fetal RPA flow in increased, likely due to partial constriction of the ductus arteriosus. However, this was not associated with PPHN.