microRNAs regulate nitric oxide release from endothelial cells by targeting NOS3

Area of Science:

• Molecular Biology
• Cardiovascular Research
• Biochemistry

Background:

• Endothelial nitric oxide synthase (eNOS), encoded by NOS3, produces nitric oxide (NO), crucial for preventing thrombosis.
• Serum microRNAs (miRNAs) like miR-195, miR-532, and miR-582 are potential deep vein thrombosis (DVT) biomarkers, but their functional roles are unclear.

Purpose of the Study:

• To investigate the in vitro effects of miR-195, miR-532, and miR-582 on NOS3 expression and endothelial nitric oxide (NO) production.
• To elucidate the regulatory mechanisms of these miRNAs on NOS3 and their implications for thrombotic diseases.

Main Methods:

• Transfection of endothelial cells with miRNA mimics and inhibitors.
• Quantification of NOS3 mRNA and protein levels using real-time qPCR and Western Blotting.
• Luciferase reporter assays to confirm direct targeting of NOS3 3'-UTR.
• Measurement of NO release via the Griess assay.

Main Results:

• NOS3 was confirmed as a direct target of miR-195 and miR-582, binding to the 3'-UTR of NOS3 mRNA.
• A significant inverse correlation was observed between miR-195/miR-582 levels and eNOS expression.
• Upregulation of miR-195 and miR-582 led to decreased NO release from endothelial cells.

Conclusions:

• miR-195 and miR-582 post-transcriptionally regulate eNOS expression by targeting the NOS3 3'-UTR in endothelial cells.
• These miRNAs play a significant role in modulating endothelial NO bioavailability.
• miR-195 and miR-582 represent novel therapeutic targets for managing thrombotic diseases.