The unexplored role of sedentary time and physical activity in glucose and lipid metabolism related placental mRNAs in obese pregnant women: The DALI Lifestyle Randomized Controlled Trial.

Abstract

OBJECTIVES\nTo explore i) the association of sedentary time (ST) and physical activity (PA) during pregnancy with placental expression of genes related to glucose and lipid metabolism in obese pregnant women; ii) maternal metabolic factors mediating changes in these placental transcripts; and iii) cord blood markers related to these mRNAs mediating neonatal adiposity.\n\n\nSTUDY DESIGN\nMulticentre-randomized controlled trial.\n\n\nSETTING\nHospitals; 9-European countries.\n\n\nPOPULATION\n112 pregnant women with placental tissue.\n\n\nEXPOSURES/OUTCOMES\nST and moderate-to-vigorous PA (MVPA) levels were objectively measured with accelerometry at three time periods in pregnancy. Placental mRNAs (PPAR-γ, FATP2, FATP3, FABP4 and GLUT1) were measured with Nanostring technology. Maternal/foetal metabolic markers and neonatal adiposity were assessed.\n\n\nRESULTS\nLarger ST, especially in early-to-middle pregnancy, was associated with lower placental FATP2 and FATP3 expression (p<0.05); whereas MVPA at baseline was inversely associated with GLUT1 mRNA (p=0.02). Although placental FATP2 and FATP3 expression were regulated by the insulin-glucose axis (p<0.05), no maternal metabolic marker mediated the association of ST/MVPA with placental mRNAs (p>0.05). Additionally, the placental FATP2 expression was inversely associated with cord blood triglycerides and free fatty acids (FFA; p<0.01). No cord blood marker mediated neonatal adiposity; except for cord blood leptin which mediated the effects of PPAR-γ on neonatal sum of skinfolds (p<0.05).\n\n\nCONCLUSIONS\nST in early-to-middle pregnancy is associated with the expression of placental genes linked to lipid transport. PA is hardly related to transporter mRNAs. Strategies aimed at reducing sedentary behaviours during pregnancy could modulate placental gene expression, which may help to prevent unfavourable fetal/maternal pregnancy outcomes.