482-P: Linagliptin Induces M2 Macrophage Polarization and Suppresses Progression of Atherosclerosis in High-Fat-Fed ApoE-Deficient Mice

Abstract

Background: Dipeptidyl peptidase-4 (DPP-4) inhibitors suppressed the progression of atherosclerosis in atherosclerotic mouse models. However, exact mechanism has been unclear. In this study, we investigated whether linagliptin suppressed progression of atherosclerosis in high fat diet (HFD)-fed apolipoprotein-E-deficient (ApoE KO) mice via anti-inflammatory effects on macrophages. Methods: HFD-fed ApoE KO mice were treated orally with linagliptin (10 mg/kg/day). After 8 weeks of treatment, whole aorta and aortic sinus were stained with Oil red O, or anti-4-Hydroxynonenal (4-HNE) and anti-F4/80 antibodies. Mouse bone marrow-derived macrophages were used in vitro study. Intracellular ROS generation was evaluated by H2DCF-DA assay. Expression of iNOS, MCP-1, TNF-α, arginase-1, Mgl2 and Ym1 mRNA, and macrophage polarization were evaluated by real-time RT-PCR and FACS scan, respectively. Results: There were no significant differences on food intake, body weight, blood glucose levels between each group, but cholesterol concentrations in VLDL and LDL particle were lower in linagliptin group. Oil-Red-O staining demonstrated that size of atherosclerotic lesions was decreased in linagliptin group. The 4-HNE-positive area and number of macrophages in plaques were decreased, and mRNA expression of arginase-1, Mgl2 and Ym1 in the aorta were higher in linagliptin groups than those in control groups. Linagliptin suppressed ROS generation, increased mRNA expression of arginase-1, Mgl2 and Ym1, and ameliorated LPS+IFNγ-induced reduction of M2 macrophages. Conclusion: This study suggests that linagliptin suppresses the progression of atherosclerosis in HFD-fed apoE KO mice. Moreover, linagliptin suppresses ROS generation and increases the polarization of M2 macrophages. These findings may indicate the beneficial effects of linagliptin for the prevention of diabetic macrovascular complications. Disclosure S. Nishida: None. T. Matsumura: None. T. Senokuchi: None. N. Ishii: None. S. Murakami-Nishida: None. S. Yamada: None. Y. Morita: None. T. Wada: None. H. Motoshima: None. T. Kondo: None. E. Araki: Research Support; Self; Astellas Pharma Inc., Boehringer Ingelheim Pharmaceuticals, Inc., Daiichi Sankyo Company, Limited, Novo Nordisk Inc., Takeda Pharmaceutical Company Limited. Speaker's Bureau; Self; Astellas Pharma Inc., Merck & Co., Inc., Novo Nordisk Inc., Ono Pharmaceutical Co., Ltd., Sanofi.