Ovidiu Ionut Geicu

Differentiation of amniotic fluid stem cells (AFSCs) into multiple lineages is controlled by epigenetic modifications, which include DNA methylation, modifications of histones, and the activity of small noncoding RNAs. The present study investigates the role of miRNAs in the differentiation of AFSCs and addresses how their unique signatures contribute to lineage-specific differentiation. The miRNA profile was assessed in AFSCs after 4 weeks of endothelial and muscular differentiation. Our results showed decreased expression of five miRNAs (miR-18a-5p, miR-125b-5p, miR-137, miR-21-5p, and let-7a) and increased expression of twelve miRNAs (miR-134-5p, miR-103a-3p, let-7i-5p, miR-214-3p, let-7c-5p, miR-129-5p, miR-210-3p, let-7d-5p, miR-375, miR-181-5p, miR-125a-5p, and hsa-let-7e-5p) in endothelial progenitor cells (EPCs) compared with undifferentiated AFSCs. AFSC differentiation into smooth muscle revealed notable changes in nine out of the 84 tested miRNAs. Among these, three miRNAs (miR-18a-5p, miR-137, and sa-miR-21-5p) were downregulated, while six miRNAs (miR-155-5p, miR-20a-5p, let-7i-5p, hsa-miR-134-5p, hsa-miR-214-3p, and hsa-miR-375) exhibited upregulation. Insights from miRNA networks promise future advancements in understanding and manipulating endothelial and muscle cell dynamics. This knowledge has the potential to drive innovation in areas like homeostasis, growth, differentiation, and vascular function, leading to breakthroughs in biomedical applications and therapies.

Epigenetic modifications play a significant role in determining the fate of AFSC in terms of differentiation into multiple lineages. There is a tight correlation among DNA methylation, histone modifications, and small noncoding RNAs during the epigenetic control of stem cells differentiation. The present study investigates the role of miRNAs in differentiation of AFSC and addresses how their unique signatures contribute to lineage-specific differentiation. miRNAs profile was assessed in AFSC after 4 weeks of endothelial and muscular differentiation. Our results showed a decreased expression of for 5 miRNAs (miR-125b-5p, hsa-miR-18a-5p, hsa-miR-137, hsa-miR-21-5p and hsa-let-7a-5p) and an increased expression for 12 miRNAs (miR-134-5p, miR-103a-3p, let-7i-5p, miR-214-3p, let-7c-5p, miR-129-5p, miR-210-3p, let-7d-5p, miR-375, miR-181-5p, miR-125a-5p, hsa-let-7e-5p) in EPC compared with undifferentiated AFSC. Smooth muscle differentiation of AFSC revealed significant changes in 9 miRNAs from total of 84 tested; 3 were downregulated (miR-18a-5p, miR-137, sa-miR-21-5p) and 6 were upregulated (miR-155-5p, miR-20a-5p, let-7i-5p, hsa-miR-134-5p, hsa-miR-214-3p, hsa-miR-375). miRNAs are molecular regulators of cell fate and differentiation, recent advances in molecular biology techniques revealed miRNA regulatory networks that can provide us information of endothelial and muscle cell biology in terms of homeostasis, growth, differentiation, and vascular function.