Characterization of choline transporters in the human placenta over gestation

Maternal Plasma Choline during Gestation and Small for Gestational Age Infants

OBJECTIVE

Small for gestational age (SGA) infants are at increased risk for neonatal morbidity and developmental problems in childhood. No current interventions during human pregnancy address this problem. This study investigated the possible relationship between maternal choline concentration during pregnancy and SGA infants.

STUDY DESIGN

Maternal plasma choline concentrations were sampled at 16 and 28 weeks' gestation from women in a public prenatal clinic. Additional factors assessed were maternal age, body mass index, infection, C-reactive protein, hair cortisol, and compliance with prenatal vitamins and folate. Infants below the 10th percentile for gestational age were classified as SGA. Binary logistic regression was used to identify significant associated factors in pregnancies resulting in SGA infants compared with pregnancies resulting in non-SGA infants.

RESULTS

Thirteen (8%) of 159 women had SGA infants. Maternal plasma choline concentrations were low for pregnant participants whose infants were SGA, with the 28-week concentration significantly lower compared with other participants. Plasma choline concentrations ≥7 μM at 28 weeks, consistent with a minimally adequate dietary intake of choline-containing foods, were achieved by only 2 (15%) of mothers with SGA infants, compared with 51% of mothers whose infants were not SGA. Choline concentrations <7 μM at 28 weeks' gestation were associated with an odds ratio for SGA of 16.6 (95% confidence interval: 1.5-189.2, p = 0.023). Other significant factors were female sex and maternal C-reactive protein plasma concentration during gestation.

CONCLUSION

This observational study suggests that higher maternal choline levels may influence the risk for SGA. Maternal plasma choline concentrations are not routinely available in clinical laboratories. However, plasma choline levels can be increased by the mothers' intake of choline or phosphatidylcholine supplements. No nutritional intervention is currently recommended to prevent SGA, but the evidence from this study suggests that further consideration of the role of maternal choline may be warranted.

KEY POINTS

· More females are small for gestational age.. · Low maternal choline is related to small infants.. · Maternal choline ≥7 μM at 28 weeks appears optimal..

Developmental Windows for Effects of Choline and Folate on Excitatory and Inhibitory Neurotransmission During Human Gestation

Choline and folate are critical nutrients for fetal brain development, but the timing of their influence during gestation has not been previously characterized. At different periods during gestation, choline stimulation of α7-nicotinic receptors facilitates conversion of γ-aminobutyric acid (GABA) receptors from excitatory to inhibitory and recruitment of GluR1-R2 receptors for faster excitatory responses to glutamate. The outcome of the fetal development of inhibition and excitation was assessed in 159 newborns by P50 cerebral auditory-evoked responses. Paired stimuli, S1, S2, were presented 500 msec apart. Higher P50 amplitude in response to S1 (P50S1microV) assesses excitation, and lower P50S2microV assesses inhibition in this paired-stimulus paradigm. Development of inhibition was related solely to maternal choline plasma concentration and folate supplementation at 16 weeks' gestation. Development of excitation was related only to maternal choline at 28 weeks. Higher maternal choline concentrations later in gestation did not compensate for earlier lower concentrations. At 4 years of age, increased behavior problems on the Child Behavior Checklist 1½-5yrs were related to both newborn inhibition and excitation. Incomplete development of inhibition and excitation associated with lower choline and folate during relatively brief periods of gestation thus has enduring effects on child development.

Choline - a scoping review for Nordic Nutrition Recommendations 2023

Choline is an essential nutrient with metabolic roles as a methyl donor in one carbon metabolism and as a precursor for membrane phospholipids and the neurotransmitter acetylcholine. Choline content is particularly high in liver, eggs, and wheat germ, although it is present in a variety of foods. The main dietary sources of choline in the Nordic and Baltic countries are meat, dairy, eggs, and grain. A diet that is devoid of choline causes liver and muscle dysfunction within 3 weeks. Choline requirements are higher during pregnancy and lactation than in non-pregnant women. Although no randomized controlled trials are available, observational studies in human, supported by coherence from interventional studies with neurodevelopmental outcomes and experimental studies in animals, strongly suggest that sufficient intake of choline during pregnancy is necessary for normal brain development and function in the child. Observational studies suggested that adequate intake of choline could have positive effects on cognitive function in older people. However, prospective data are lacking, and no intervention studies are available in the elderly.

The role of maternal choline, folate and one-carbon metabolism in mediating the impact of prenatal alcohol exposure on placental and fetal development

Prenatal alcohol consumption (PAE) may be associated with a broad spectrum of impacts, ranging from no overt effects, to miscarriage, fetal growth restriction and fetal alcohol spectrum disorder. A major mechanism underlying the effects of PAE is considered to be altered DNA methylation and gene expression. Maternal nutritional status may be an important factor in determining the extent to which PAE impacts pregnancy outcomes, particularly the dietary micronutrients folate and choline because they provide methyl groups for DNA methylation via one carbon metabolism. This review summarises the roles of folate and choline in development of the blastocyst, the placenta and the fetal brain, and examines the evidence that maternal intake of these micronutrients can modify the effects of PAE on development. Studies of folate or choline deficiency have found reduced blastocyst development and implantation, reduced placental invasion, vascularisation and nutrient transport capability, impaired fetal brain development, and abnormal neurodevelopmental outcomes. PAE has been shown to reduce absorption and/or metabolism of folate and choline and to produce similar outcomes to maternal choline/folate deficiency. A few studies have demonstrated that the effects of PAE on brain development can be ameliorated by folate or choline supplementation; however, there is very limited evidence on the effects of supplementation in early pregnancy on the blastocyst and placenta. Further studies are required to support these findings and to determine optimal supplementation parameters.

Preventive effects of antenatal CDP-choline in a rat model of neonatal hyperoxia-induced lung injury

Antenatal steroid administration to pregnant women at risk of prematurity provides pulmonary maturation in infants, while it has limited effects on incidence of bronchopulmonary dysplasia (BPD), the clinical expression of hyperoxia-induced lung injury (HILI). Cytidine-5'-diphosphate choline (CDP-choline) was shown to alleviate HILI when administered to newborn rats. Therefore, we investigated effects of maternal administration of CDP-choline, alone or in combination with betamethasone, on lung maturation in neonatal rats subjected to HILI immediately after birth. Pregnant rats were randomly assigned to one of the four treatments: saline (1 mL/kg), CDP-choline (300 mg/kg), betamethasone (0.4 mg/kg), or CDP-choline plus betamethasone (combination therapy). From postnatal day 1 to 11, pups born to mothers in the same treatment group were pooled and randomly assigned to either normoxia or hyperoxia group. Biochemical an d histopathological effects of CDP-choline on neonatal lung tissue were evaluated. Antenatal CDP-choline treatment increased levels of phosphatidylcholine and total lung phospholipids, decreased apoptosis, and improved alveolarization. The outcomes were further improved with combination therapy compared to the administration of CDP-choline or betamethasone alone. These results demonstrate that antenatal CDP-choline treatment provides benefit in experimental HILI either alone or more intensively when administered along with a steroid, suggesting a possible utility for CDP-choline against BPD.

Prenatal choline, cannabis, and infection, and their association with offspring development of attention and social problems through 4 years of age

BACKGROUND

Prenatal choline is a key nutrient, like folic acid and vitamin D, for fetal brain development and subsequent mental function. We sought to determine whether effects of higher maternal plasma choline concentrations on childhood attention and social problems, found in an initial clinical trial of choline supplementation, are observed in a second cohort.

METHODS

Of 183 mothers enrolled from an urban safety net hospital clinic, 162 complied with gestational assessments and brought their newborns for study at 1 month of age; 83 continued assessments through 4 years of age. Effects of maternal 16 weeks of gestation plasma choline concentrations ⩾7.07 μM, 1 s.d. below the mean level obtained with supplementation in the previous trial, were compared to lower levels. The Attention Problems and Withdrawn Syndrome scales on Child Behavior Checklist 1½-5 were the principal outcomes.

RESULTS

Higher maternal plasma choline was associated with lower mean Attention Problems percentiles in children, and for male children, with lower Withdrawn percentiles. Higher plasma choline concentrations also reduced Attention Problems percentiles for children of mothers who used cannabis during gestation as well as children of mothers who had gestational infection.

CONCLUSIONS

Prenatal choline's positive associations with early childhood behaviors are found in a second, more diverse cohort. Increases in attention problems and social withdrawal in early childhood are associated with later mental illnesses including attention deficit disorder and schizophrenia. Choline concentrations in the pregnant women in this study replicate other research findings suggesting that most pregnant women do not have adequate choline in their diets.

Prenatal Choline Supplementation Alters One Carbon Metabolites in a Rat Model of Periconceptional Alcohol Exposure

Prenatal alcohol exposure disturbs fetal and placental growth and can alter DNA methylation (DNAm). Supplementation with the methyl donor choline can increase fetal and placental growth and restore DNAm, suggesting converging effects on one-carbon metabolism (1CM). We investigated the impact of periconceptional ethanol (PCE) exposure and prenatal choline supplementation on 1CM in maternal, placental, and fetal compartments. Female Sprague Dawley rats were given a liquid diet containing 12.5% ethanol (PCE) or 0% ethanol (control) for 4 days before and 4 days after conception. Dams were then placed on chow with different concentrations of choline (1.6 g, 2.6 g, or 7.2 g choline/kg chow). Plasma and tissues were collected in late gestation for the analysis of 1CM components by means of mass spectrometry and real-time PCR. PCE reduced placental components of 1CM, particularly those relating to folate metabolism, resulting in a 3−7.5-fold reduction in the ratio of s-adenosylmethionine:s-adenosylhomocysteine (SAM:SAH) (p < 0.0001). Choline supplementation increased placental 1CM components and the SAM:SAH ratio (3.5−14.5-fold, p < 0.0001). In the maternal and fetal compartments, PCE had little effect, whereas choline increased components of 1CM. This suggests that PCE impairs fetal development via altered placental 1CM, highlighting its role in modulating nutritional inputs to optimize fetal development.

Micronutrients of the one-carbon metabolism cycle are altered in mothers and neonates by gestational diabetes and are associated with weight, height and head circumference at birth

While several studies have previously described the levels of one-carbon metabolism-related micronutrients in women with gestational diabetes mellitus (GDM) and their neonates, the results in these literature reports have been contradictory. We hypothesized that the concentrations of micronutrients involved in the one-carbon cycle are altered in pregnant women and their neonates by GDM, and that these changes could further modify the neonatal anthropometry. Micronutrient levels were measured in 123 pregnant women with normal glucose levels (M-ND) and their neonates (N-ND), as well as in 54 pregnant women with gestational diabetes (M-GDM) and their neonates (M-GDM). Folate and vitamin B12 levels were measured via competitive ELISA, and betaine, choline, and glycine levels were measured via ultra-high performance liquid chromatography-mass spectrometry (UHPLC-MS/MS). Vitamin B12 and Glycine were found to be higher in M-GDM compared to M-ND. N-GDM had higher levels of folic acid and vitamin B12 and lower levels of betaine and choline compared to N-ND. In general, neonates presented with high concentrations of micronutrients compared to their mothers, and the fetus/maternal ratio of micronutrients was higher among the N-ND as compared to the N-GDM. Micronutrients were also variably associated with anthropometric measurements. The association of betaine with neonatal anthropometry in N-GDM is highlighted. In summary, our results implicate a potential role of GDM in altering the levels of one-carbon metabolism-related micronutrients among pregnant women and their neonates. Likewise, our results also elucidate a potential association between the concentrations of micronutrients and the weight, height, and head circumference of neonates.

Urinary metabolomics reveals the biological characteristics of early pregnancy in pigs

Background

Embryo implantation in sows is an important event during pregnancy. During this process, blastocysts undergo dramatic morphologic changes, and the endometrium becomes receptive. Studies have shown that developmental changes associated with the crosstalk between peri-implantation embryos and embryo-uterine are driven by various biomolecules secreted by the endometrium and embryos. In sows, changes in the uterus are also reflected in circulating body fluids and urine. Metabolomics reveals the metabolic state of cells, tissues, and organisms. In this study, we collected urine samples from large white sows during the peri-implantation period. The levels of urinary metabolites at different periods were analyzed using ultra-performance liquid chromatography/tandem mass spectrometry (UPLC–MS/MS) analysis techniques.

Results

A total of 32 samples were collected from 8 sows during the estrus period and at each phase of early pregnancy (9, 12, and 15 days of gestation). A total of 530 metabolites were identified with high confidence in all samples. Compared with samples collected during the estrus phase, 269 differential metabolites were found in samples obtained during early pregnancy.

Conclusions

The identified metabolites included lipids and lipid-like molecules, organic acids and their derivatives, organic oxygen compounds, organoheterocyclic compounds, benzenoids, among others. Metabolites, such as choline and pregnanediol-3-glucuronide, play important roles in pregnancy in sows and other animals. These results reveal the metabolic changes in urine of sows during early pregnancy phase. The differential urinary metabolites can be used for assessing peri-implantation status in sows. Understanding these metabolic changes may promote the management of pregnant sows through various interventions such as provision of proper nutrition.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40813-022-00256-z.

Choline metabolome response to prenatal choline supplementation across pregnancy: A randomized controlled trial

Pregnancy places a unique stress upon choline metabolism, requiring adaptations to support both maternal and fetal requirements. The impact of pregnancy and prenatal choline supplementation on choline and its metabolome in free-living, healthy adults is relatively uncharacterized. This study investigated the effect of prenatal choline supplementation on maternal and fetal biomarkers of choline metabolism among free-living pregnant persons consuming self-selected diets. Participants were randomized to supplemental choline (as choline chloride) intakes of 550 mg/d (500 mg/d d0-choline + 50 mg/d methyl-d9-choline; intervention) or 25 mg/d d9-choline (control) from gestational week (GW) 12-16 until Delivery. Fasting blood and 24-h urine samples were obtained at study Visit 1 (GW 12-16), Visit 2 (GW 20-24), and Visit 3 (GW 28-32). At Delivery, maternal and cord blood and placental tissue samples were collected. Participants randomized to 550 (vs. 25) mg supplemental choline/d achieved higher (p < .05) plasma concentrations of free choline, betaine, dimethylglycine, phosphatidylcholine (PC), and sphingomyelin at one or more study timepoint. Betaine was most responsive to prenatal choline supplementation with increases (p ≤ .001) in maternal plasma observed at Visit 2-Delivery (relative to Visit 1 and control), as well as in the placenta and cord plasma. Notably, greater plasma enrichments of d3-PC and LDL-C were observed in the intervention (vs. control) group, indicating enhanced PC synthesis through the de novo phosphatidylethanolamine N-methyltransferase pathway and lipid export. Overall, these data show that prenatal choline supplementation profoundly alters the choline metabolome, supporting pregnancy-related metabolic adaptations and revealing biomarkers for use in nutritional assessment and monitoring during pregnancy.

Identification of 371 genetic variants for age at first sex and birth linked to externalising behaviour

Age at first sexual intercourse and age at first birth have implications for health and evolutionary fitness. In this genome-wide association study (age at first sexual intercourse, N = 387,338; age at first birth, N = 542,901), we identify 371 single-nucleotide polymorphisms, 11 sex-specific, with a 5-6% polygenic score prediction. Heritability of age at first birth shifted from 9% [CI = 4-14%] for women born in 1940 to 22% [CI = 19-25%] for those born in 1965. Signals are driven by the genetics of reproductive biology and externalising behaviour, with key genes related to follicle stimulating hormone (FSHB), implantation (ESR1), infertility and spermatid differentiation. Our findings suggest that polycystic ovarian syndrome may lead to later age at first birth, linking with infertility. Late age at first birth is associated with parental longevity and reduced incidence of type 2 diabetes and cardiovascular disease. Higher childhood socioeconomic circumstances and those in the highest polygenic score decile (90%+) experience markedly later reproductive onset. Results are relevant for improving teenage and late-life health, understanding longevity and guiding experimentation into mechanisms of infertility.

Maternal choline supplementation in a rat model of periconceptional alcohol exposure: Impacts on the fetus and placenta

BACKGROUND

Maternal choline supplementation in rats can ameliorate specific neurological and behavioral abnormalities caused by alcohol exposure during pregnancy. We tested whether choline supplementation ameliorates fetal growth restriction and molecular changes in the placenta associated with periconceptional ethanol exposure (PCE) in the rat.

METHODS

Sprague Dawley dams were given either 12.5% ethanol (PCE) or 0% ethanol (Con) in a liquid diet from 4 days prior to 4 days after conception. At day 5 of pregnancy, dams were either placed on a standard chow (1.6 g choline/kg chow) or an intermediate chow (2.6 g choline/kg chow). On day 10 of pregnancy, a subset of the intermediate dams were placed on a chow further supplemented with choline (7.2 g choline/kg chow), resulting in 6 groups. Fetuses and placentas were collected on day 20 of pregnancy for analysis.

RESULTS

Choline supplementation resulted in increased fetal weight at late gestation, ameliorating the deficits due to PCE. This was most pronounced in litters on a standard chow during pregnancy. Choline also increased fetal liver weight and decreased fetal brain:liver ratio, independent of alcohol exposure. Placental weight was reduced as choline levels in the chow increased, particularly in female placentas. This resulted in a greater ratio of fetal:placental weight, suggesting increased placental efficiency. Global DNA methylation in the placenta was altered in a sex-specific manner by both PCE and choline. However, the increased glycogen deposition in female placentas, previously reported in this PCE model, was not prevented by choline supplementation.

CONCLUSIONS

Our results suggest that choline has the potential to ameliorate fetal growth restriction associated with PCE and improve placental efficiency following prenatal alcohol exposure. Our study highlights the importance of maternal nutrition in moderating the severity of adverse fetal and placental outcomes that may arise from prenatal alcohol exposure around the time of conception.

Male fetus susceptibility to maternal inflammation: C-reactive protein and brain development

BACKGROUND

Maternal inflammation in early pregnancy has been identified epidemiologically as a prenatal pathogenic factor for the offspring's later mental illness. Early newborn manifestations of the effects of maternal inflammation on human fetal brain development are largely unknown.

METHODS

Maternal infection, depression, obesity, and other factors associated with inflammation were assessed at 16 weeks gestation, along with maternal C-reactive protein (CRP), cytokines, and serum choline. Cerebral inhibition was assessed by inhibitory P50 sensory gating at 1 month of age, and infant behavior was assessed by maternal ratings at 3 months of age.

RESULTS

Maternal CRP diminished the development of cerebral inhibition in newborn males but paradoxically increased inhibition in females. Similar sex-dependent effects were seen in mothers' assessment of their infant's self-regulatory behaviors at 3 months of age. Higher maternal choline levels partly mitigated the effect of CRP in male offspring.

CONCLUSIONS

The male fetal-placental unit appears to be more sensitive to maternal inflammation than females. Effects are particularly marked on cerebral inhibition. Deficits in cerebral inhibition 1 month after birth, similar to those observed in several mental illnesses, including schizophrenia, indicate fetal developmental pathways that may lead to later mental illness. Deficits in early infant behavior follow. Early intervention before birth, including prenatal vitamins, folate, and choline supplements, may help prevent fetal development of pathophysiological deficits that can have life-long consequences for mental health.

Interaction of maternal choline levels and prenatal Marijuana's effects on the offspring

BACKGROUND

This study investigated whether higher maternal choline levels mitigate effects of marijuana on fetal brain development. Choline transported into the amniotic fluid from the mother activates α7-nicotinic acetylcholine receptors on fetal cerebro-cortical inhibitory neurons, whose development is impeded by cannabis blockade of their cannabinoid-1(CB1) receptors.

METHODS

Marijuana use was assessed during pregnancy from women who later brought their newborns for study. Mothers were informed about choline and other nutrients, but not specifically for marijuana use. Maternal serum choline was measured at 16 weeks gestation.

RESULTS

Marijuana use for the first 10 weeks gestation or more by 15% of mothers decreased newborns' inhibition of evoked potentials to repeated sounds (d' = 0.55, p < 0.05). This effect was ameliorated if women had higher gestational choline (rs = -0.50, p = 0.011). At 3 months of age, children whose mothers continued marijuana use through their 10th gestational week or more had poorer self-regulation (d' = -0.79, p < 0.05). This effect was also ameliorated if mothers had higher gestational choline (rs = 0.54, p = 0.013). Maternal choline levels correlated with the children's improved duration of attention, cuddliness, and bonding with parents.

CONCLUSIONS

Prenatal marijuana use adversely affects fetal brain development and subsequent behavioral self-regulation, a precursor to later, more serious problems in childhood. Stopping marijuana use before 10 weeks gestational age prevented these effects. Many mothers refuse to cease use because of familiarity with marijuana and belief in its safety. Higher maternal choline mitigates some of marijuana's adverse effects on the fetus.

In vitro culture and non-invasive metabolic profiling of single bovine embryos

Selecting high-quality embryos for transfer has been a difficult task when producing bovine embryos invitro. The most used non-invasive method is based on visual observation. Molecular characterisation of embryo growth media has been proposed as a complementary method. In this study we demonstrate a culture medium sampling method for identifying potential embryonic viability markers to predict normal or abnormal embryonic development. During single embryo culture, 20µL culture media was removed at Days 2, 5 and 8 after fertilisation from the same droplet (60µL). In all, 58 samples were analysed using liquid chromatography-mass spectrometry. We demonstrate that it is possible to remove samples from the same culture medium droplets and not significantly affect blastocyst rate (25.2%). Changes in any single low molecular weight compound were not predictive enough. Combining multiple low molecular weight signals made it possible to predict Day 2 and 5 embryo development to the blastocyst stage with an accuracy of 64%. Elevated concentrations of lysophosphatidylethanolamines (m/z=453, 566, 588) in the culture media of Day 8 well-developing embryos were observed. Choline (104m/z) and citrate (215m/z) concentrations were increased in embryos in which development was retarded. Metabolic profiling provides possibilities to identify well-developing embryos before transfer, thus improving pregnancy rates and the number of calves born.

Higher Gestational Choline Levels in Maternal Infection Are Protective for Infant Brain Development

OBJECTIVE

To assess whether maternal choline decreases effects of mothers' infections on fetal brain circuit development and on expression of infant behavior at 1 year of age.

STUDY DESIGN

A cross-sectional study was conducted in a public hospital obstetrics and midwifery service, with prenatal assessments of maternal infection, C-reactive protein, and choline level and postnatal assessments of cerebral neuronal inhibition in 162 newborns. At 1 year, 136 parents completed reports of their child's behavior.

RESULTS

Maternal infection at 16 weeks of gestation, experienced by 41% of mothers, raised mean maternal C-reactive protein (d' = 0.47, P = .002) and decreased the development of cerebral inhibition of auditory response at 1 month of age (d' = 0.39, P < .001). Decreased newborn cerebral inhibition manifested as decreased behavioral self-regulation at 1 year. Greater choline levels in mothers with infections were associated with improved newborn inhibition of auditory cerebral response, mitigating the effect of infection (β = -0.34 [95% CI, -5.35 to -0.14], P = .002). At 1 year of age, children of mothers with infection and greater gestational choline levels had improved development of self-regulation, approaching the level of children of mothers without infection (β = 0.29 [95% CI 0.05-0.54], P = .03).

CONCLUSIONS

Greater maternal choline, recommended by the American Medical Association as a prenatal supplement, is associated with greater self-regulation among infants who experienced common maternal infections during gestation. Behavioral problems with diminished self-regulation often lead to referrals to pediatricians and might lead to later mental illness.

Folate and choline absorption and uptake: Their role in fetal development

SCOPE

In this review, we attempt to assess how choline and folate transporters affect fetal development. We focus on how the expression of these transporters in response to choline and folate intake affects transport effectiveness. We additionally describe allelic variants of the genes encoding these transporters and their phenotypic effects.

METHODS AND RESULTS

We made an extensive review of recent articles describing role of choline and folate - with particularly emphasize on their transporters - in fetal development. Folate and choline are necessary for the proper functioning of the cell and body. During pregnancy, the requirements of these nutrients increase because of elevated maternal demand and the rapid division of fetal cells. The concentrations of folate and choline in cells depend on food intake, the absorption of nutrients, and the cellular transport system, which is tissue-specific and developmentally regulated. Relatively few studies have investigated the role of choline transporters in fetal development.

CONCLUSIONS

In this review we show relations between functioning of folate and choline transporters and fetal development.

Adverse placental effects of valproic acid: Studies in perfused human placentas

OBJECTIVE

In utero exposure to valproic acid (VPA) has been associated with worse pregnancy outcomes compared to all other antiepileptic drugs. We have previously shown that VPA alters the expression of placental transporters for hormones and nutrients in vitro and in pregnant mice. Here, our aim was to characterize the effects of short exposure to VPA on the expression of carriers for compounds essential for fetal development in human placentas ex vivo, under controlled conditions.

METHODS

Placentas were obtained from cesarean deliveries of women with no known epilepsy. Cotyledons were cannulated and perfused in the absence or the presence of VPA (42, 83, or 166 μg/mL; n = 6/group) in the maternal perfusate over 180 minutes. A customized gene panel array was used to analyze the expression of carrier genes in the perfused cotyledons. We additionally measured in the perfused placentas folic acid concentrations and histone acetylation.

RESULTS

VPA significantly altered the mRNA levels of major carriers for folic acid, glucose, choline, thyroid hormones, and serotonin (P < .05) and reduced placental folate concentrations by 25%-35% (P = .059). The effects were observed at therapeutic concentrations sufficient to enhance placental histone acetylation, and some were concentration-dependent.

SIGNIFICANCE

Our results point to the placenta as a novel target of VPA, implying potential involvement of the placenta in VPA's adverse fetal outcomes.