Maternal Choline Supplementation Modulates Placental Markers of Inflammation, Angiogenesis, and Apoptosis in a Mouse Model of Placental Insufficiency.

Dlx3 (distal-less homeobox 3) haploinsufficiency in mice has been shown to result in restricted fetal growth and placental defects. We previously showed that maternal choline supplementation (4X versus 1X choline) in the Dlx3+/- mouse increased fetal and placental growth in mid-gestation. The current study sought to test the hypothesis that prenatal choline would modulate indicators of placenta function and development. Pregnant Dlx3+/- mice consuming 1X (control), 2X, or 4X choline from conception were sacrificed at embryonic (E) days E10.5, E12.5, E15.5, and E18.5, and placentas and embryos were harvested. Data were analyzed separately for each gestational day controlling for litter size, fetal genotype (except for models including only +/- pups), and fetal sex (except when data were stratified by this variable). 4X choline tended to increase (p < 0.1) placental labyrinth size at E10.5 and decrease (p < 0.05) placental apoptosis at E12.5. Choline supplementation decreased (p < 0.05) expression of pro-angiogenic genes Eng (E10.5, E12.5, and E15.5), and Vegf (E12.5, E15.5); and pro-inflammatory genes Il1b (at E15.5 and 18.5), Tnfα (at E12.5) and Nfκb (at E15.5) in a fetal sex-dependent manner. These findings provide support for a modulatory effect of maternal choline supplementation on biomarkers of placental function and development in a mouse model of placental insufficiency.

Maternal choline supplementation during murine pregnancy modulates placental markers of inflammation, apoptosis and vascularization in a fetal sex-dependent manner.

INTRODUCTION: Normal placental vascular development is influenced by inflammatory, angiogenic and apoptotic processes, which may be modulated by choline through its role in membrane biosynthesis, cellular signaling and gene expression regulation. The current study examined the effect of maternal choline supplementation (MCS) on placental inflammatory, angiogenic and apoptotic processes during murine pregnancy. METHOD: Pregnant dams were randomized to receive 1, 2 or 4 times (X) the normal choline content of rodent diets, and tissues were harvested on embryonic day (E) 10.5, 12.5, 15.5 or 18.5 for gene expression, protein abundance and immunohistochemical analyses. RESULTS: The choline-induced changes in the inflammatory and angiogenic markers were a function of fetal sex. Specifically, 4X (versus 1X) choline reduced the transcript (P ≤ 0.05) and protein (P ≤ 0.06) expression of TNF-a and IL-1ß in the male placentas at E10.5 and E18.5, respectively. In the female placentas, 4X (versus 1X) choline modulated the transcript expression of Il1b in a biphasic pattern with reduced Il1b at E12.5 (P = 0.045) and E18.5 (P = 0.067) but increased Il1b at E15.5 (P = 0.031). MCS also induced an upregulation of Vegfa expression in the female placentas at E15.5 (P = 0.034; 4X versus 2X) and E18.5 (P = 0.026; 4X versus 1X). MCS decreased (P = 0.011; 4X versus 1X) placental apoptosis at E10.5. Additionally, the luminal area of the maternal spiral arteries was larger (P ≤ 0.05; 4X versus 1X) in response to extra choline throughout gestation. DISCUSSION: MCS during murine pregnancy has fetal sex-specific effects on placental inflammation and angiogenesis, with possible consequences on placental vascular development.

Genetic Variation in Choline-Metabolizing Enzymes Alters Choline Metabolism in Young Women Consuming Choline Intakes Meeting Current Recommendations.

Single nucleotide polymorphisms (SNPs) in choline metabolizing genes are associated with disease risk and greater susceptibility to organ dysfunction under conditions of dietary choline restriction. However, the underlying metabolic signatures of these variants are not well characterized and it is unknown whether genotypic differences persist at recommended choline intakes. Thus, we sought to determine if common genetic risk factors alter choline dynamics in pregnant, lactating, and non-pregnant women consuming choline intakes meeting and exceeding current recommendations. Women (n = 75) consumed 480 or 930 mg choline/day (22% as a metabolic tracer, choline-d9) for 10-12 weeks in a controlled feeding study. Genotyping was performed for eight variant SNPs and genetic differences in metabolic flux and partitioning of plasma choline metabolites were evaluated using stable isotope methodology. CHKA rs10791957, CHDH rs9001, CHDH rs12676, PEMT rs4646343, PEMT rs7946, FMO3 rs2266782, SLC44A1 rs7873937, and SLC44A1 rs3199966 altered the use of choline as a methyl donor; CHDH rs9001 and BHMT rs3733890 altered the partitioning of dietary choline between betaine and phosphatidylcholine synthesis via the cytidine diphosphate (CDP)-choline pathway; and CHKA rs10791957, CHDH rs12676, PEMT rs4646343, PEMT rs7946 and SLC44A1 rs7873937 altered the distribution of dietary choline between the CDP-choline and phosphatidylethanolamine N-methyltransferase (PEMT) denovo pathway. Such metabolic differences may contribute to disease pathogenesis and prognosis over the long-term.