This study provided the first evidence that omentin-1 may serve as a novel therapeutic target for atherosclerosis and CAD.

A therosclerosis is a pathological injury-to-response process that is initiated by early inflammatory responses of vascular endothelial cells (ECs).1 Endothelial inflammation is characterized by increased production of proatherogenic molecules and inflammatory cytokines in ECs, and monocyte adhesion and infiltration into the neointima lesion, followed by oxidized low-density lipoprotein-induced transformation of macrophages into foam cells.2 Accumulation of cholesterol ester in macrophages is a hallmark of foam cell formation. 2This accumulation depends on the balance between the uptake of oxidized low-density lipoprotein via CD36 and the efflux of free cholesterol controlled by ATP-binding cassette transporter A1 (ABCA1), ATP-binding cassette transporter G1, or scavenger receptor class B type I (SR-BI).3 To protect the cells from the toxicity that would result from excessive free cholesterol accumulation, the free cholesterol is esterified to cholesterol ester by acyl-CoA:cholesterol acyltransferase-1 (ACAT1).3 Cholesterol ester stored in lipid droplets can be removed from cells only after hydrolysis to free cholesterol by neutral cholesterol ester hydrolase. 4 Apart from accumulation of macrophage-derived foam cells, the migration and proliferation of vascular smooth muscle cells (VSMCs) followed by extracellular matrix (ECM) production play crucial roles in the development of atherosclerotic lesions. 1Cardiotrophin 1 (CT-1), a 201-aa member of the interleukin-6 cytokine family, was originally cloned from embryoid bodies as a 21.5-kDa protein capable of inducing hypertrophy in neonatal cardiomyocytes. 5 Human and mouse CT-1 share 80% amino acid sequence identity and exhibit cross-species activity.6 Subsequent studies confirmed that plasma concentrations of CT-1 are elevated in various cardiorenal diseases, such as hypertension, ischemic heart disease, heart failure, and chronic renal disease.7-10 CT-1 exerts cardiovascular remodeling induced by hypertensive and ischemic heart diseases and congestive heart failure, through its receptor complex glycoprotein 130 (gp130) and leukemia inhibitory factor receptor (LIFR).11-14 Recently, CT-1 has been shown to be expressed in the intima in the early stages of atherosclerotic lesions in human carotid artery.15 CT-1 stimulates the synthesis of inflammatory cytokines and proatherogenic molecules, such as interleukin-6, Abstract-Cardiotrophin 1 (CT-1), an interleukin-6 family cytokine, was recently shown to be expressed in the intima of early atherosclerotic lesions in the human carotid artery. CT-1 stimulates proatherogenic molecule expression in human vascular endothelial cells and monocyte migration. However, it has not been reported whether CT-1 accelerates atherosclerosis. This study was performed to examine the stimulatory effects of CT-1 on human macrophage foam cell formation and vascular smooth muscle cell migration and proliferation in vitro, and on the development of atherosclerotic lesions in apolipoprotein E-deficient (ApoE −/− ) mice in vivo. CT-1 was express...

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Cardiotrophin-1 (CT-1), an interleukin-6 family cytokine, is known as an active inducer capable of cardiac hypertrophy and vascular stiffness in hypertensive heart disease. CT-1 is expressed at high levels in the heart, vascular endothelial cells (ECs), and adipocytes. CT-1 stimulates inflammatory and proatherogenic molecule expression in human monocytes and ECs, as well as monocyte-EC adhesion. CT-1 enhances oxidized low-density lipoprotein-induced foam-cell formation in human monocyte-derived macrophages. CT-1 stimulates the migration, proliferation, and colloagen-1 production in human vascular smooth muscle cells. Chronic CT-1 infusion into Apoe −/− mice accelerates the development of aortic atherosclerotic lesions. CT-1 is expressed at high levels in ECs and macrophage foam cells within atheromatous plaques in Apoe −/− mice. A blockade of CT-1 using anti-CT-1 neutralizing antibody results in the prevention of atherogenesis in Apoe −/− mice. Plasma CT-1 concentrations are elevated in patients with hypertensive heart disease, ischemic heart disease, and metabolic syndrome, and are positively associated with the severity of cardiac hypertrophy, heart failure, and atherosclerosis. Increased plasma concentration of CT-1 is a predictor of death and heart failure following acute myocardial infarction. Therefore, CT-1 serves a novel therapeutic target for atherosclerosis and related diseases. Plasma CT-1 may be a reliable biomarker for atherosclerotic cardiovascular diseases.J 2018, 1 95 have provided the first evidence that CT-1 is expressed at high levels in atherosclerotic lesions and shows proatherogenic effects [15]. Other studies have reported that plasma concentrations of CT-1 are increased in patients with coronary artery disease (CAD) [16].The present review introduces the recent accumulating evidence regarding the roles of CT-1 in the pathophysiology of atherosclerosis and the potential biomarker of cardiovascular and metabolic diseases. Structure, Expression, and Function of CT-1CT-1 is a new member of the interleukin (IL)-6 cytokine family that was originally cloned from a mouse embryoid body cDNA library based on its ability to induce hypertrophy in neonatal cardiomyocytes [17]. cDNA clones of human CT-1 were isolated by screening a heart cDNA library with a mouse CT-1 probe [17]. The DNA sequence of these clones encodes a protein of 201 amino acids that is 80% identical with the 203 amino acid residue of mouse CT-1 [18]. CT-1 has a molecular weight of 21.5 kDa. Human and mouse CT-1 lack a conventional, hydrophobic, N-terminal amino acid sequence indicative of a secretion signal [18]. The amino acid sequence of rat CT-1 is 80% and 94% identical to those of human CT-1 and mouse CT-1, respectively [19]. The coding region of CT-1 is contained on 3 exons and is located on human chromosome 16p11.1-16p11.2 [18].CT-1 is expressed in the cardiovascular system as well as the brain, thymus, lungs, kidneys, liver, intestine, testes, prostate, skeletal muscles, and adipose tissue [18][19][20][21][22][23]. In cardiov...

Introduction: Omentin-1, a novel adipocytokine expressed in visceral fat tissue, is negatively correlated with obesity, insulin resistance, and stable coronary artery disease (CAD). However, there have been no previous reports regarding the effects of omentin-1 on atherogenesis. Objective and Methods: We aimed to evaluate the atheroprotective effects of omentin-1 on human monocyte-derived macrophages, human aortic smooth muscle cells (HASMCs) in vitro , and aortic lesions in apolipoprotein E-deficient (ApoE -/- ) mice in vivo . The histological expression of omentin-1 in coronary artery lesions and epicardial adipose tissues and its plasma levels were compared between CAD and non-CAD patients. Results: Omentin-1 was abundantly expressed in human umbilical vein endothelial cells, macrophages, HASMCs, and human coronary artery SMCs in vitro . Omentin-1 promoted antiinflammatory M2 phenotype via PPAR-γ upregulation and NF-κB downregulation during differentiation of human monocytes into macrophages. Omentin-1 suppressed oxidized LDL-induced foam cell formation associated with downregulation of CD36, scavenger receptor class A, and acyl-CoA:cholesterol acyltransferase-1 and upregulation of neutral cholesterol ester hydrolase in human macrophages. In HASMCs, omentin-1 suppressed angiotensin II-induced migration and PDGF-BB-induced proliferation, and collagen-1 and collagen-3 expressions via ERK1/2 and NF-κB downregulation. Four-week infusion of omentin-1 into ApoE -/- mice retarded the development of aortic atherosclerotic lesions with reduced contents of monocytes/macrophages, SMCs, and collagen fibers. In addition, it increased peritoneal M2-activated macrophages, downregulated inflammasomes such as CRP, NF-κB, COX-2, and apoptosis-associated speck-like protein containing a caspase recruitment domain, and lowered plasma total cholesterol levels in ApoE -/- mice. Omentin-1 levels were markedly reduced in coronary endothelium and epicardial fat but increased in plasma and atheromatous plaques (macrophages/SMCs) in CAD patients compared with non-CAD patients. Conclusions: Our translational research provided the first evidence that omentin-1 may serve as a novel therapeutic target for atherosclerosis and CAD.