Global microRNA and protein expression in human term placenta.

Description of the global expression of microRNAs (miRNAs) and proteins in healthy human term placentas may increase our knowledge of molecular biological pathways that are important for normal fetal growth and development in term pregnancy. The aim of this study was to explore the global expression of miRNAs and proteins, and to point out functions of importance in healthy term placentas. Placental samples (n = 19) were identified in a local biobank. All samples were from uncomplicated term pregnancies with vaginal births and healthy, normal weight newborns. Next-generation sequencing and nano-scale liquid chromatographic tandem mass spectrometry were used to analyse miRNA and protein expression, respectively. A total of 895 mature miRNAs and 6,523 proteins were detected in the placentas, of which 123 miRNAs and 346 proteins were highly abundant. The miRNAs were in high degree mapped to chromosomes 19, 14 and X. Analysis of the highly abundant miRNAs and proteins showed several significantly predicted functions in common, including immune and inflammatory response, lipid metabolism and development of the nervous system. The predicted function inflammatory response may reflect normal vaginal delivery, while lipid metabolism and neurodevelopment may be important processes for the term fetus. The data presented in this study, including supplementary information with complete miR Overall design: Placental tissue sampled from healthy women. The inclusion criteria were healthy women without chronic disease or malabsorption disorder, a normal body mass index (BMI) 18.5–24.9 in early pregnancy, gestational weight gain within the recommended interval of 11.5–16.0 kg (23) and age 18–35 years at the time of delivery. Further, the woman had to give birth vaginally to a healthy, singleton infant with a normal birth weight defined as +/- 1 SD from the population mean (24) at gestational age 37+0 to 41+6. Maternal exclusion criteria were smoking during pregnancy, any long-term treatment with medicines (excepting folic acid and iron supplements), any pregnancy complications (e.g. gestational hypertension, preeclampsia, gestational diabetes or erythrocyte immunization), preterm premature rupture of membranes, chorionamnionitis, mechanical induction or induction of labour with prostaglandins, or an active second stage of labour > 60 minutes. Fetal exclusion criteria were asphyxia (defined as Apgar score < 7 at 5 minutes), and chromosomal or severe anatomical malformation of the newborn infant. Next-generation sequencing was used to analyse placental expression of miRNA.