Journal Article

Maternal Factors Are Associated with the Expression of Placental Genes Involved in Amino Acid Metabolism and Transport

Ntani, Georgia, Mahon, Pam A., Crozier, Sarah R., Cooper, Cyrus, Hanson, Mark A., Harvey, Nicholas C., Lewis, Rohan M., Cleal, Jane K., Day, Pricilla E., Inskip, Hazel M., Godfrey, Keith M.

2015

Overview

Maternal environment and lifestyle factors may modify placental function to match the mother's capacity to support the demands of fetal growth. Much remains to be understood about maternal influences on placental metabolic and amino acid transporter gene expression. We investigated the influences of maternal lifestyle and body composition (e.g. fat and muscle content) on a selection of metabolic and amino acid transporter genes and their associations with fetal growth. RNA was extracted from 102 term Southampton Women's Survey placental samples. Expression of nine metabolic, seven exchange, eight accumulative and three facilitated transporter genes was analyzed using quantitative real-time PCR. Increased placental LAT2 (p = 0.01), y+LAT2 (p = 0.03), aspartate aminotransferase 2 (p = 0.02) and decreased aspartate aminotransferase 1 (p = 0.04) mRNA expression associated with pre-pregnancy maternal smoking. Placental mRNA expression of TAT1 (p = 0.01), ASCT1 (p = 0.03), mitochondrial branched chain aminotransferase (p = 0.02) and glutamine synthetase (p = 0.05) was positively associated with maternal strenuous exercise. Increased glutamine synthetase mRNA expression (r = 0.20, p = 0.05) associated with higher maternal diet quality (prudent dietary pattern) pre-pregnancy. Lower LAT4 (r = -0.25, p = 0.05) and aspartate aminotransferase 2 mRNA expression (r = -0.28, p = 0.01) associated with higher early pregnancy diet quality. Lower placental ASCT1 mRNA expression associated with measures of increased maternal fat mass, including pre-pregnancy BMI (r = -0.26, p = 0.01). Lower placental mRNA expression of alanine aminotransferase 2 associated with greater neonatal adiposity, for example neonatal subscapular skinfold thickness (r = -0.33, p = 0.001). A number of maternal influences have been linked with outcomes in childhood, independently of neonatal size; our finding of associations between placental expression of transporter and metabolic genes and maternal smoking, physical activity and diet raises the possibility that their effects are mediated in part through alterations in placental function. The observed changes in placental gene expression in relation to modifiable maternal factors are important as they could form part of interventions aimed at maintaining a healthy lifestyle for the mother and for optimal fetal development.

• Publisher: Public Library of Science,Public Library of Science (PLoS)
• Subject: Acids / Adipose tissue / Adult / Alanine / Alanine transaminase / Amino Acid Transport Systems - genetics / Amino Acid Transport Systems - metabolism / Amino acids / Amino Acids - genetics / Amino Acids - metabolism / Aspartate aminotransferase / Biological Transport / Biomedical research / Body composition / Body fat / Body mass / Chain branching / Children / Diabetes / Diet / Enzymes / Epidemiology / Exercise / Female / Fetuses / Gene Expression / Gene-Environment Interaction / Genes / Glutamate-ammonia ligase / Glutamine / Health risk assessment / Humans / Influence / Life sciences / Life Style / Lifestyles / Metabolism / Mitochondria / Muscles / Neonates / Physical activity / Placenta / Placenta - metabolism / Placenta - physiology / Pregnancy / Prenatal development / Real-Time Polymerase Chain Reaction / Ribonucleic acid / RNA / RNA, Messenger - genetics / RNA, Messenger - metabolism / Skinfold thickness / Smoking / Studies