Glucagon-like Peptide-1 Suppresses the Proliferation and Migration of Vascular Smooth Muscle Cells: Implications for Preventive Effects on Atherosclerosis

Abstract

Our group previously demonstrated the suppressive effect of glucagon-like peptide-1 (GLP-1) on macrophage-driven atherosclerosis in apolipoprotein E-deficient (apoE^-/-) mice. In the present study we investigated the suppressive effect of GLP-1 on the atherogenic phenotype of vascular smooth muscle cells (VSMCs) in vivo using apoE^-/- mice, and the proliferation and migration of human VSMCs in vitro. A 4-week infusion of GLP-1 in 17-week-old apoE^-/- mice significantly reduced the proliferative VSMC phenotype stained with SMemb. Platelet-derived growth factor (PDGF) -BB significantly stimulated the proliferation of human aortic VSMCs by three fold. Both 0.1 and 1nmol/l GLP-1 significantly suppressed the PDGF-induced VSMC proliferation, and this suppressive effect was significantly abolished by the GLP-1 receptor antagonist exendin (9-39) (50nmol/l). The GLP-1 receptor agonists liraglutide (100nmol/l) and exendin-4 (100nmol/l) mimicked GLP-1, significantly suppressing PDGF-induced VSMC proliferation. PDGF-BB significantly stimulated the migration of human aortic VSMCs by 1.7 -fold, and this effect was significantly suppressed by 1nmol/l GLP-1. These findings suggest that GLP-1-related treatments may prevent the progression of atherosclerotic lesions by suppressing the proliferation and migration of VSMCs, which are characteristic features of atherosclerosis.