Abstract 18542: Genetic Ablation of miR-33 Attenuates Inflammation and Reduces Abdominal Aortic Aneurysm Formation

Introduction: Abdominal aortic aneurysm (AAA) pathogenesis is characterized by inflammation and matrix degradation, part of which are observed in atherosclerosis. Despite statins are only clinically effective agents for AAA, their effects are limited and more effective therapies are expected. Previous studies suggested that microRNA(miR)-33 inhibition and genetic ablation of miR-33 increase serum HDL cholesterol (HDL-C) and attenuates atherosclerosis. Although several miRs are reported to affect AAA, such miRs which target cholesterol metabolism have not been reported ever. Hypothesis: MiR-33 may be involved in AAA pathogenesis, and anti-miR-33 can be an effective therapy. Methods: We assessed the phenotypic difference of CaCl2-induced and Angiotensin(AT)II-induced AAA models between miR-33+/+ and miR-33-/- mice. To elucidate the underling mechanisms, we assessed the functions of macrophages (MΦ), primary aortic vascular smooth muscle cells (VSMCs) and HDL-C between these mice. Results: CaCl2-induced AAA ...