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.

A higher maternal choline intake among third-trimester pregnant women lowers placental and circulating concentrations of the antiangiogenic factor fms-like tyrosine kinase-1 (sFLT1).

This study investigated the influence of maternal choline intake on the human placental transcriptome, with a special interest in its role in modulating placental vascular function. Healthy pregnant women (n=26, wk 26-29 gestation) were randomized to 480 mg choline/d, an intake level approximating the adequate intake of 450 mg/d, or 930 mg/d for 12 wk. Maternal blood and placental samples were retrieved at delivery. Whole genome expression microarrays were used to identify placental genes and biological processes impacted by maternal choline intake. Maternal choline intake influenced a wide array of genes (n=166) and biological processes (n=197), including those related to vascular function. Of special interest was the 30% down-regulation (P=0.05) of the antiangiogenic factor and preeclampsia risk marker fms-like tyrosine kinase-1 (sFLT1) in the placenta tissues obtained from the 930 vs. 480 mg/d choline intake group. Similar decreases (P=0.04) were detected in maternal blood sFLT1 protein concentrations. The down-regulation of sFLT1 by choline treatment was confirmed in a human trophoblast cell culture model and may be related to enhanced acetylcholine signaling. These findings indicate that supplementing the maternal diet with extra choline may improve placental angiogenesis and mitigate some of the pathological antecedents of preeclampsia.

Maternal choline intake alters the epigenetic state of fetal cortisol-regulating genes in humans.

The in utero availability of methyl donors, such as choline, may modify fetal epigenetic marks and lead to sustainable functional alterations throughout the life course. The hypothalamic-pituitary-adrenal (HPA) axis regulates cortisol production and is sensitive to perinatal epigenetic programming. As an extension of a 12-wk dose-response choline feeding study conducted in third-trimester pregnant women, we investigated the effect of maternal choline intake (930 vs. 480 mg/d) on the epigenetic state of cortisol-regulating genes, and their expression, in placenta and cord venous blood. The higher maternal choline intake yielded higher placental promoter methylation of the cortisol-regulating genes, corticotropin releasing hormone (CRH; P=0.05) and glucocorticoid receptor (NR3C1; P=0.002); lower placental CRH transcript abundance (P=0.04); lower cord blood leukocyte promoter methylation of CRH (P=0.05) and NR3C1 (P=0.04); and 33% lower (P=0.07) cord plasma cortisol. In addition, placental global DNA methylation and dimethylated histone H3 at lysine 9 (H3K9me2) were higher (P=0.02) in the 930 mg choline/d group, as was the expression of select placental methyltransferases. These data collectively suggest that maternal choline intake in humans modulates the epigenetic state of genes that regulate fetal HPA axis reactivity as well as the epigenomic status of fetal derived tissues.

Trends in hospitalizations of newborns with hyperbilirubinemia and kernicterus in United States: an epidemiological study.

BACKGROUND: Hyperbilirubinemia is one of the most common diagnosis in newborn nurseries in United States. Universal pre-discharge bilirubin screening decreased the incidence of extreme hyperbilirubinemia and risk of kernicterus. OBJECTIVES: We sought to assess temporal population trends of hyperbilirubinemia, kernicterus and usage of phototherapy, intravenous immunoglobulin (IVIG), and exchange transfusion. DESIGN/METHODS: Data from Healthcare Cost and Utilization Project (HCUP)-the Kids' Inpatient Database (KID) obtained for years 1997-2012. All neonatal discharges with ICD-9 codes for neonatal jaundice (774.2, 774.6), kernicterus (773.4, 774.7) and procedure codes for phototherapy (99.83), IVIG infusion (99.14), exchange transfusion (99.01) were extracted. We compared the trends of diagnosis of hyperbilirubinemia, kernicterus, use of phototherapy, IVIG, and exchange transfusion. RESULTS: During the study period, the proportion of infants diagnosed with hyperbilirubinemia increased by 65% (9.4% vs. 15.5%; p<.001) in term infants and 34.5% (33.5% vs. 45%; p<.001) in preterm infants, respectively. Rate of kernicterus discharges significantly reduced from 7 to 1.9 per 100,000 newborns. Overall, the number of exchange transfusions has decreased by 67% during study period while phototherapy and IVIG use increased by 83% and 170%, respectively. CONCLUSIONS: In last two decades, there was a significant decrease in neonatal discharges with a history of exchange transfusion or with a diagnosis of kernicterus. However, there was a significant increase in number of neonates discharged home with a history of phototherapy during birth hospitalization and decreased number of exchange transfusions were observed during the study period. Incremental implementation of universal predischarge bilirubin screening and treatments based on 2004 AAP recommended risk-based strategies might have contributed to timely interventions in infants with significant hyperbilirubinemia.

Prenatal choline supplementation improves biomarkers of maternal docosahexaenoic acid (DHA) status among pregnant participants consuming supplemental DHA: a randomized controlled trial.

BACKGROUND: Dietary methyl donors (e.g., choline) support the activity of the phosphatidylethanolamine N-methyltransferase (PEMT) pathway, which generates phosphatidylcholine (PC) molecules enriched in DHA that are exported from the liver and made available to extrahepatic tissues. OBJECTIVES: This study investigated the effect of prenatal choline supplementation on biomarkers of DHA status among pregnant participants consuming supplemental DHA. METHODS: Pregnant participants (n = 30) were randomly assigned to receive supplemental choline intakes of 550 mg/d [500 mg/d d0-choline + 50 mg/d deuterium-labeled choline (d9-choline); intervention] or 25 mg/d (25 mg/d d9-choline; control) from gestational week (GW) 12-16 until delivery. All participants received a daily 200-mg DHA supplement and consumed self-selected diets. Fasting blood samples were obtained at baseline, GW 20-24, and GW 28-32; maternal/cord blood was obtained at delivery. Mixed-effects linear models were used to assess the impact of prenatal choline supplementation on maternal and newborn DHA status. RESULTS: Choline supplementation (550 vs. 25 mg/d) did not achieve a statistically significant intervention × time interaction for RBC PC-DHA (P = 0.11); a significant interaction was observed for plasma PC-DHA and RBC total DHA, with choline supplementation yielding higher levels (+32-38% and +8-11%, respectively) at GW 28-32 (P < 0.05) and delivery (P < 0.005). A main effect of choline supplementation on plasma total DHA was also observed (P = 0.018); its interaction with time was not significant (P = 0.068). Compared with controls, the intervention group exhibited higher (P = 0.007; main effect) plasma enrichment of d3-PC (d3-PC/total PC). Moreover, the ratio of d3-PC to d9-PC was higher (+50-67%; P < 0.001) in the choline intervention arm (vs. control) at GW 20-24, GW 28-32, and delivery. CONCLUSIONS: Prenatal choline supplementation improves hepatic DHA export and biomarkers of DHA status by bolstering methyl group supply for PEMT activity among pregnant participants consuming supplemental DHA. This trial is registered at www.clinicaltrials.gov as NCT03194659.

Branched chain fatty acids are constituents of the normal healthy newborn gastrointestinal tract.

Vernix suspended in amniotic fluid is normally swallowed by the late term fetus. We hypothesized that branched chain fatty acids (BCFA), long known to be major vernix components, would be found in meconium and that the profiles would differ systematically. Vernix and meconium were collected from term newborns and analyzed. BCFA-containing lipids constituted about 12% of vernix dry weight, and were predominantly saturated, and had 11-26 carbons per BCFA. In contrast, meconium BCFA had 16-26 carbons, and were about 1% of dry weight. Meconium BCFA were mostly in the iso-configuration, whereas vernix BCFA contained dimethyl and middle chain branching, and five anteiso-BCFA. The mass of BCFA entering the fetal gut as swallowed vernix particles is estimated to be 180 mg in the last month of gestation whereas the total mass of BCFA found in meconium is estimated to be 16 mg, thus most BCFA disappear from the fetal gut. The BCFA profiles of vernix and meconium show that BCFA are major components of normal healthy term newborn gastrointestinal tract. BCFA are candidates for agents that play a role in gut colonization and should be considered a nutritional component for the fetus/newborn.

A Unique Genomic Variant of HDR Syndrome in Newborn.

BACKGROUND: HDR syndrome (also known as Barakat syndrome) is a rare genetic disorder due to deletions/mutations on specific regions of zinc-finger transcription factor (GATA3) gene. CASE CHARACTERISTICS: A male preterm infant presented with multiple dysmorphic features characterized by small for gestational age, hypognathia and facial abnormalities. OBSERVATION: Investigations revealed hypocalcemia and low parathyroid hormone levels and bilateral sensorineural deafness. OUTCOME: Chromosomal microarray analysis revealed a combination of deletion on chromosome 10p (10p15.3p14) with loss of GATA3 gene and duplication of chromosome 20p (20p13p12.3) as a result of unbalanced 10:20 translocation. MESSAGE: Detecting this syndrome at neonatal age is very important because it allows early intervention to minimize future clinical problems.

Effect of enteral glutamine or glycine on whole-body nitrogen kinetics in very-low-birth-weight infants.

BACKGROUND: Glutamine is a critical amino acid for the metabolism of enterocytes, lymphocytes, and other proliferating cells. Although supplementation with glutamine has been suggested for growing infants, its effect on protein metabolism has not been examined. OBJECTIVE: The objective was to examine the effect of enteral glutamine or glycine on whole-body kinetics of glutamine, phenylalanine, leucine, and urea in preterm infants. DESIGN: Infants at <32 wk of gestation were given formula supplemented with either glutamine (0.6 g. kg(-1). d(-1); n = 9) or isonitrogenous amounts of glycine (n = 9) for 5 d. Eight infants fed unsupplemented formula served as control subjects. Glutamine, phenylalanine, leucine nitrogen flux, leucine carbon flux, and urea kinetics were quantified during a basal fasting period and in response to nutrient intake. RESULTS: Growing preterm infants had a high weight-specific rate of appearance of glutamine, phenylalanine, and leucine nitrogen flux. When compared with the control treatment, enteral glutamine resulted in a high rate of urea synthesis, no change in the plasma glutamine concentration, and no change in the rate of appearance of glutamine. Glycine supplementation resulted in similar changes in nitrogen metabolism, but the magnitude of change was less than that in the glutamine group. In the nonsupplemented infants, the rate of appearance of leucine nitrogen flux was negatively correlated (rho = -0.72) with urea synthesis. In contrast, the correlation (rho = 0.75) was positive in the glutamine group. CONCLUSION: Enterally administered glutamine in growing preterm infants is entirely metabolized in the gut and does not have a discernable effect on whole-body protein and nitrogen kinetics.

Maternal choline intake modulates maternal and fetal biomarkers of choline metabolism in humans.

BACKGROUND: In 1998 choline Adequate Intakes of 425 and 450 mg/d were established for nonpregnant and pregnant women, respectively. However, to our knowledge, no dose-response studies have been conducted to evaluate the effects of pregnancy or maternal choline intake on biomarkers of choline metabolism. OBJECTIVE: We sought to quantify the effects of pregnancy and maternal choline intake on maternal and fetal indicators of choline metabolism. DESIGN: Healthy pregnant (n = 26; 27 wk gestation) and nonpregnant (n = 21) women were randomly assigned to receive 480 or 930 mg choline/d for 12 wk. Fasting blood samples and placental tissue and umbilical cord venous blood were collected and analyzed for choline and its metabolites. RESULTS: Regardless of the choline intake, pregnant women had higher circulating concentrations of choline (30%; P < 0.001) but lower concentrations of betaine, dimethylglycine, sarcosine, and methionine (13-55%; P < 0.001). Obligatory losses of urinary choline and betaine in pregnant women were ∼2-4 times as high (P ≤ 0.02) as those in nonpregnant women. A higher choline intake yielded higher concentrations of choline, betaine, dimethylglycine, and sarcosine (12-46%; P ≤ 0.08) in both pregnant and nonpregnant women without affecting urinary choline excretion. The higher maternal choline intake also led to a doubling of dimethylglycine in cord plasma (P = 0.002). CONCLUSION: These data suggest that an increment of 25 mg choline/d to meet the demands of pregnancy is insufficient and show that a higher maternal choline intake increases the use of choline as a methyl donor in both maternal and fetal compartments. This trial was registered at clinicaltrials.gov as NCT01127022.

Pregnancy induces transcriptional activation of the peripheral innate immune system and increases oxidative DNA damage among healthy third trimester pregnant women.

BACKGROUND: Pregnancy induces physiological adaptations that may involve, or contribute to, alterations in the genomic landscape. Pregnancy also increases the nutritional demand for choline, an essential nutrient that can modulate epigenomic and transcriptomic readouts secondary to its role as a methyl donor. Nevertheless, the interplay between human pregnancy, choline and the human genome is largely unexplored. METHODOLOGY/PRINCIPAL FINDINGS: As part of a controlled feeding study, we assessed the influence of pregnancy and choline intake on maternal genomic markers. Healthy third trimester pregnant (n = 26, wk 26-29 gestation) and nonpregnant (n = 21) women were randomized to choline intakes of 480 mg/day, approximating the Adequate Intake level, or 930 mg/day for 12-weeks. Blood leukocytes were acquired at study week 0 and study week 12 for microarray, DNA damage and global DNA/histone methylation measurements. A main effect of pregnancy that was independent of choline intake was detected on several of the maternal leukocyte genomic markers. Compared to nonpregnant women, third trimester pregnant women exhibited higher (P<0.05) transcript abundance of defense response genes associated with the innate immune system including pattern recognition molecules, neutrophil granule proteins and oxidases, complement proteins, cytokines and chemokines. Pregnant women also exhibited higher (P<0.001) levels of DNA damage in blood leukocytes, a genomic marker of oxidative stress. No effect of choline intake was detected on the maternal leukocyte genomic markers with the exception of histone 3 lysine 4 di-methylation which was lower among pregnant women in the 930 versus 480 mg/d choline intake group. CONCLUSIONS: Pregnancy induces transcriptional activation of the peripheral innate immune system and increases oxidative DNA damage among healthy third trimester pregnant women.

Glutamine and leucine nitrogen kinetics and their relation to urea nitrogen in newborn infants.

Glutamine kinetics and its relation to transamination of leucine and urea synthesis were quantified in 16 appropriate-for-gestational-age infants, four small-for-gestational-age infants, and seven infants of diabetic mothers. Kinetics were measured between 4 and 5 h after the last feed (fasting) and in response to formula feeding using [5-(15)N]glutamine, [1-(13)C,(15)N]leucine, [(2)H(5)]phenylalanine, and [(15)N(2)]urea tracers. Leucine nitrogen and glutamine kinetics during fasting were significantly higher than those reported in adults. De novo synthesis accounted for approximately 85% of glutamine turnover. In response to formula feeding, a significant increase (P = 0.04) in leucine nitrogen turnover was observed, whereas a significant decrease (P = 0.002) in glutamine and urea rate of appearance was seen. The rate of appearance of leucine nitrogen was positively correlated (r(2) = 0.59, P = 0.001) with glutamine turnover. Glutamine flux was negatively correlated (r(2) = 0.39, P = 0.02) with the rate of urea synthesis. These data suggest that, in the human newborn, glutamine turnover is related to a high anaplerotic flux into the tricarboxylic acid cycle as a consequence of a high rate of protein turnover. The negative relationship between glutamine turnover and the irreversible oxidation of protein (urea synthesis) suggests an important role of glutamine as a nitrogen source for other synthetic processes and accretion of body proteins.