microRNA-491-5p protects against atherosclerosis by targeting matrix metallopeptidase-9

Area of Science:

• Cardiovascular Biology
• Molecular Medicine
• Biomarker Discovery

Background:

• Vascular smooth muscle cell (VSMC) proliferation and migration are key drivers of atherosclerosis.
• Understanding the regulatory mechanisms of VSMC behavior is crucial for developing effective treatments.

Purpose of the Study:

• To investigate the role of microRNA-491-5p (miR-491-5p) in regulating VSMC growth and migration in atherosclerosis.
• To identify the molecular targets of miR-491-5p involved in atherosclerotic progression.

Main Methods:

• Expression analysis of miR-491-5p and matrix metallopeptidase-9 (MMP-9) in patient samples.
• Bioinformatic analysis and dual-luciferase reporter assays to confirm MMP-9 as a miR-491-5p target.
• In vitro studies using VSMCs to assess the effects of miR-491-5p modulation on cell proliferation, migration, and apoptosis.

Main Results:

• miR-491-5p expression was significantly downregulated in atherosclerotic tissues and plasma.
• MMP-9 expression was upregulated in atherosclerosis and identified as a direct target of miR-491-5p.
• Downregulation of miR-491-5p promoted VSMC proliferation and migration while inhibiting apoptosis; conversely, miR-491-5p mimic suppressed these processes.
• Overexpression of MMP-9 reversed the effects of miR-491-5p mimic on VSMCs.

Conclusions:

• miR-491-5p acts as a tumor suppressor in atherosclerosis by inhibiting VSMC proliferation and migration.
• The miR-491-5p/MMP-9 axis represents a novel regulatory pathway in atherosclerosis.
• miR-491-5p holds potential as a diagnostic biomarker and therapeutic target for atherosclerosis.