RESUMO
Plasma levels of chemerin, an adipocytokine produced from the adipose tissues and liver, are associated with metabolic syndrome and coronary artery disease (CAD). Chemerin and its analog, chemerin-9, are known to bind to their receptor, ChemR23. However, whether chemerin and chemerin-9 affect atherogenesis remains to be elucidated. We investigated the expression of chemerin and ChemR23 in human coronary arteries and cultured human vascular cells. The effects of chemerin and chemerin-9 on atheroprone phenomena were assessed in human THP1 monocytes, human umbilical vein endothelial cells (HUVECs), and human aortic smooth muscle cells (HASMCs) and aortic lesions in Apoe-/- mice. In patients with CAD, a small amount of ChemR23, but not chemerin, was expressed within atheromatous plaques in coronary arteries. Chemerin and ChemR23 were expressed at high levels in THP1 monocytes, THP1-derived macrophages, and HUVECs; however, their expression in HASMCs was weak. Chemerin and chemerin-9 significantly suppressed the tumor necrosis factor-α (TNF-α)-induced mRNA expression of adhesion and pro-inflammatory molecules in HUVECs. Chemerin and chemerin-9 significantly attenuated the TNF-α-induced adhesion of THP1 monocytes to HUVECs and macrophage inflammatory phenotype. Chemerin and chemerin-9 suppressed oxidized low-density lipoprotein (oxLDL)-induced macrophage foam cell formation associated with down-regulation of CD36 and up-regulation of ATP-binding cassette transporter A1 (ABCA1). In HASMCs, chemerin and chemerin-9 significantly suppressed migration and proliferation without inducing apoptosis. In the Apoe-/- mice, a 4-week infusion of chemerin-9 significantly decreased the areas of aortic atherosclerotic lesions by reducing intraplaque macrophage and SMC contents. Our results indicate that chemerin-9 prevents atherosclerosis. Therefore, the development of chemerin analogs/ChemR23 agonists may serve as a novel therapeutic target for atherosclerotic diseases.
Assuntos
Aterosclerose/metabolismo , Quimiocinas/metabolismo , Receptores de Quimiocinas/metabolismo , Animais , Células Cultivadas , Vasos Coronários/metabolismo , Células Endoteliais da Veia Umbilical Humana , Humanos , Masculino , Camundongos , Camundongos Knockout , Músculo Liso Vascular/metabolismoRESUMO
BACKGROUND: Kisspeptin-10 (KP-10), a potent vasoconstrictor and inhibitor of angiogenesis, and its receptor, GPR54, have currently received much attention in relation to pre-eclampsia. However, it still remains unknown whether KP-10 could affect atherogenesis. METHODS AND RESULTS: We evaluated the effects of KP-10 on human umbilical vein endothelial cells, human monocyte-derived macrophages, human aortic smooth muscle cells in vitro, and atherosclerotic lesions in apolipoprotein E-deficient (ApoE-/-) mice in vivo. KP-10 significantly increased the adhesion of human monocytes to human umbilical vein endothelial cells, which was significantly inhibited by pretreatment with P234, a GPR54 antagonist. KP-10 stimulated mRNA expression of tumor necrosis factor-α, interleukin-6, monocyte chemotactic protein-1, intercellular adhesion molecule-1, vascular adhesion molecule-1, and E-selectin in human umbilical vein endothelial cells. KP-10 significantly enhanced oxidized low-density lipoprotein-induced foam cell formation associated with upregulation of CD36 and acyl-CoA:cholesterol acyltransferase-1 in human monocyte-derived macrophages. In human aortic smooth muscle cells, KP-10 significantly suppressed angiotensin II-induced migration and proliferation, but enhanced apoptosis and activities of matrix metalloproteinase (MMP)-2 and MMP-9 by upregulation of extracellular signal-regulated kinase 1 and 2, p38, Bcl-2-associated X protein, and caspase-3. Four-week-infusion of KP-10 into ApoE-/- mice significantly accelerated the development of aortic atherosclerotic lesions with increased monocyte/macrophage infiltration and vascular inflammation as well as decreased intraplaque vascular smooth muscle cells contents. Proatherosclerotic effects of endogenous and exogenous KP-10 were completely canceled by P234 infusion in ApoE-/- mice. CONCLUSIONS: Our results suggest that KP-10 may contribute to accelerate the progression and instability of atheromatous plaques, leading to plaque rupture. The GPR54 antagonist may be useful for prevention and treatment of atherosclerosis. Thus, the KP-10/GPR54 system may serve as a novel therapeutic target for atherosclerotic diseases.