Exogenous oxytocin modulates human myometrial microRNAs.

Area of Science:

• Reproductive biology
• Molecular endocrinology
• Genomics

Background:

• MicroRNAs (miRNAs) are key regulators of gene expression.
• Oxytocin is a critical hormone involved in initiating labor.
• The role of oxytocin in modulating myometrial miRNA expression during human labor is not fully understood.

Purpose of the Study:

• To identify specific microRNAs (miRNAs) in the pregnant human myometrium whose expression is regulated by oxytocin.
• To investigate the role of oxytocin in modulating gene expression related to parturition.

Main Methods:

• Compared myometrial miRNA expression profiles between women before and after labor onset with oxytocin treatment using microarray analysis.
• Utilized multivariate modeling to identify differentially expressed miRNAs.
• Performed biologic validation in independent patient cohorts and in vitro studies using primary myocytes.

Main Results:

• Analysis of 1309 miRNAs revealed 494 detected in human myometrium.
• Multivariate modeling identified 12 key miRNAs differentiating patient populations.
• Oxytocin independently regulated 5 specific miRNAs (hsa-miR-146b-3p, hsa-miR-196b-3p, hsa-miR-223-3p, hsa-miR-873-5p, and hsa-miR-876-5p).
• hsa-miR-146b-3p expression increased in both induced and spontaneous labor groups compared to pre-labor samples.
• In vitro oxytocin treatment of primary myocytes replicated observed in vivo changes for four validated miRNAs.

Conclusions:

• Oxytocin significantly alters the expression of a distinct set of myometrial miRNAs.
• These findings highlight oxytocin's role as a signaling molecule in regulating gene expression during human parturition.
• The identified miRNAs represent potential targets for understanding and managing labor onset.