Placental expression of miR-21-5p, miR-210-3p and miR-141-3p: relation to human fetoplacental growth

Background/Objectives Dysregulation of microRNAs (miRNAs) and their target genes in placental tissue is associated with foetal growth restriction. We aimed to evaluate associations of placental miR-21-5p, miR-141-3p and miR-210-3p expression with maternal, placental and newborn parameters and with placental expression of their potential target genes PTEN, VEGF, FLT and ENG in a set of well-characterized small- (SGA) and appropriate- (AGA) for gestational age full-term singleton pregnancies. Subjects/Methods Placental samples (n = 80) from 26 SGA and 54 AGA were collected from full-term singleton pregnancies. Placental transcript abundances of miR-21-5p, miR-141-3p and miR-210-3p were assessed after normalization to a reference miRNA, mir-16-5p by real-time quantitative PCR. Placental transcript abundances of PTEN, VEGF, FLT and ENG were assessed after normalizing to a panel of reference genes. Results Placental miR-21-5p transcript abundance was negatively associated with placental weight (n = 80, r = -0.222, P = 0.047) and this association was specific to the AGA births (n = 54, r = -0.292, P = 0.032). Placental transcript abundances of miR-210-3p and miR-141-3p were not associated with placental weight or birth weight in all 80 births. However, placental miR-210-3p transcript abundance was positively associated with birth weight specifically in the SGA births (n = 26, r = 0.449, P = 0.021). Placental transcript abundance of miR-21-5p was negatively associated with PTEN transcript abundance (Spearman's rho = -0.245, P = 0.028) while that of miR-141-3p was positively associated with FLT (Spearman's rho = 0.261, P = 0.019) and ENG (Spearman's rho = 0.259, P = 0.020) transcript abundances in all 80 births. Conclusion We conclude that placental miR-21-5p and miR-210-3p may be involved in fetoplacental growth. However, this regulation is unlikely to be mediated through placental expression of PTEN, VEGF, FLT or ENG.

Automated summary

The study investigated the association of placental miRNAs (miR-21-5p, miR-141-3p, and miR-210-3p) expression with maternal, placental, and newborn parameters. The results suggest that miR-21-5p and miR-210-3p may be involved in placental growth, but not mediated through placental expression of PTEN, VEGF, FLT, or ENG.