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ARS Home » Southeast Area » Little Rock, Arkansas » Microbiome and Metabolism Research Unit » Research » Publications at this Location » Publication #347386

Title: Associations between maternal early pregnancy body mass index (BMI) and placental DNA methylation at term

item THAKALI, KESHARI - Arkansas Children'S Nutrition Research Center (ACNC)
item ZHONG, YING - Arkansas Children'S Nutrition Research Center (ACNC)
item ANDRES, ALINE - Arkansas Children'S Nutrition Research Center (ACNC)
item SHANKAR, KARTIK - Arkansas Children'S Nutrition Research Center (ACNC)

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 9/1/2017
Publication Date: N/A
Citation: N/A

Interpretive Summary:

Technical Abstract: The placenta serves as the definitive maternal-fetal interface and mediates exchange of nutrients, gases, and waste between mother and the developing fetus. The placenta integrates signals from both mother and baby, coordinating maternal nutrient supply with fetal demand and development. In epidemiological studies, maternal obesity and obesogenic diets are associated with fetal overgrowth and greater risk of obesity and metabolic dysfunction in later-life. Animal and human studies have shown maternal obesity-associated alterations in placental gene expression and implicated altered placental nutrient transport in excessive fetal growth and developmental programming. We hypothesized that placental epigenetic patterns are associated with maternal early pregnancy BMI or maternal diet composition. Maternal BMI was assessed at <10 weeks of gestation and maternal macronutrient diet composition was assessed by 3-day food records every 6 weeks during pregn Using Reduced Representation Bisulfite Sequencing (RRBS), we digitally assessed genome scale DNA methylation of approximately 300,000 CpGs in 150 placenta (N=72 normal weight mothers, N=78 overweight/obese mothers). In multivariable linear regression models adjusted for multiple testing and covariates (maternal age at delivery, infant sex, and delivery mode), maternal early pregnancy BMI, but not maternal percent of calories from fat, protein, and carbohydrates was significantly associated with placental DNA methylation of specific CpGs. Of the 54 CpGs significantly associated with maternal early pregnancy BMI (q<0.02), gene ontology analysis of the proximal genes associated with these differentially-methylated CpGs showed biological processes related to metabolism and development to be affected, and molecular functions such as protein, nucleotide, chromatin, and lipid binding, and transporter activity to be differentially methylated. These data suggest that maternal obesity, as assessed by early pregnancy BMI, has a greater effect on placental DNA methylation patterns than maternal diet composition.