neuropeptide-y and Atherosclerosis

Diabetes-induced atherosclerotic cardiovascular disease is the leading cause of death of diabetic patients. Neuronal regulation plays a critical role in glucose metabolism and cardiovascular function under physiological and pathological conditions, among which, neurotransmitter neuropeptide Y has been shown to be closely involved in these two processes. Elevated central neuropeptide Y level promotes food intake and reduces energy expenditure, thereby increasing adiposity. Neuropeptide Y is co-localized with noradrenaline in central and sympathetic nervous systems. As a major peripheral vascular contractive neurotransmitter, through interactions with its receptors, neuropeptide Y has been implicated in the pathology and progression of diabetes, by promoting the proliferation of endothelial cells and vascular fibrosis, which may contribute to diabetes-induced cardiovascular disease. Neuropeptide Y also participates in the pathogenesis of atherosclerosis, the major form of cardiovascular disease, via aggravating endothelial dysfunction, growth of vascular smooth muscle cells, formation of foam cells and platelets aggregation. This review highlights the causal role of neuropeptide Y and its receptor system in the development of diabetes mellitus and one of its complications: atherosclerotic cardiovascular disease. The information from this review provides both critical insights onto the mechanisms underlying the pathogenesis of atherosclerosis and evidence for the development of therapeutic strategies.

Topics: Animals; Arteries; Atherosclerosis; Diabetic Angiopathies; Humans; Neuropeptide Y; Prognosis; Receptors, Neuropeptide Y; Risk Factors; Signal Transduction

Neuropeptide Y (NPY) is a central neuromodulator and peripheral sympathetic neurotransmitter that also has important regulatory roles in cardiovascular, neuroendocrine, immune and metabolic functions during stress. Focusing on the peripheral actions of the peptide in rodent models, we summarize recent studies from our laboratory demonstrating that stress-induced release of NPY mediates accelerated atherosclerosis/restenosis, obesity and metabolic-like syndrome, particularly when combined with a high fat, high sugar diet. In this review, we propose mechanisms of NPY's actions, its receptors and cellular substrates that increase the risk for cardiovascular and metabolic diseases when chronic stress is associated with pre-existing vascular injury and/or states of hypernutrition.

Topics: Animals; Atherosclerosis; Cardiovascular Diseases; Humans; Metabolic Diseases; Models, Biological; Neuropeptide Y; Obesity; Overnutrition; Stress, Physiological

Topics: Atherosclerosis; Blood Vessels; Dipeptidyl Peptidase 4; Humans; Muscle, Smooth, Vascular; Neovascularization, Physiologic; Neuropeptide Y; Pentanoic Acids; Serine Proteinase Inhibitors; Thiazoles; Thiazolidines; Vasoconstriction

Neuropeptide Y (NPY) is a sympathetic neurotransmitter and a stress mediator with pleiotropic activities mediated by multiple receptors, Y1-Y5. Originally known as an appetite stimulant and a vasoconstrictor, NPY has recently emerged as a growth factor for a variety of cells from vascular smooth muscle to neural precursors - implicating the peptide in atherosclerosis and tissue remodeling. NPY is also potently angiogenic, and was hailed as a potential candidate for a nerve-driven ischemic revascularization. To determine if the latter, beneficial activity of the peptide can be separated from its deleterious pro-atherosclerotic action - receptor specificity and mechanisms of this "Janus phenomenon" were studied. Expression of Y2 receptors on the endothelium, and Y1 receptors on vascular smooth muscle, were required for angiogenic and pro-atherosclerotic activities, respectively. Amplification of both activities was provided by co-expression of Y5 receptors. In rodent models, limb ischemia up-regulated the NPY-Y2 system, which contributed to post-ischemic revascularization; exogenous NPY further augmented it and nearly normalized blood flow and function of ischemic tissues. NPY-induced angiogenesis was also dependent on nitric oxide and endothelial dipeptidyl peptidase IV (DPPIV, which converts NPY to Y2/Y5-selective agonist), but resistant to Y1 receptor blockade. Conversely, vascular angioplasty up-regulated the NPY-Y1 system and promoted atherosclerosis and hyperplastic remodeling, and these activities were blocked by Y1 receptor antagonist and augmented by DPPIV inhibitors. Thus, drugs targeting specific NPY receptors may become new therapeutics against atherosclerosis/restenosis (Y1-selective antagonists) or for ischemic revascularization (Y2-selective agonists). Such drugs may be particularly beneficial for patients with elevated circulating NPY levels e.g. by chronic stress.

Topics: Animals; Atherosclerosis; Disease Models, Animal; Drug Delivery Systems; Humans; Ischemia; Neovascularization, Physiologic; Neuropeptide Y; Receptors, Neuropeptide Y

The dysregulation of lipid metabolic pathways (cholesterol uptake and efflux) in macrophages results in the formation of lipid-dense macrophages, named foam cells, that participate in plaque formation. NPY binding to NPY receptors in macrophages can modulate cell functions and affect the process of atherosclerotic plaques. The present study aimed to determine whether NPY affects the formation of macrophage-derived foam cells and its underlying mechanisms in macrophages. THP-1-derived macrophages were incubated with oxidized low-density lipoprotein (ox-LDL) and treated with different concentrations of NPY. We analysed the relative levels of proteins related to cholesterol uptake and efflux. We found that NPY effectively increased cholesterol uptake and intracellular cholesterol content via the Y1 and Y5 receptors, and this effect was blocked by Y1 and Y5 antagonists. Mechanistically, NPY enhanced the expression of SRA and CD36 via the PKC/PPARγ pathways, promoting macrophage cholesterol uptake. Moreover, NPY significantly decreased cholesterol efflux to the extracellular cholesterol acceptors ApoA1 and HDL in macrophages. NPY mediated decreases in ABCA1, ABCG1 and SR-BI expression through the inhibition of the JAK/STAT3 pathways. Our results suggest that NPY binding to the Y1 and Y5 receptors enhances foam cell formation by regulating cholesterol uptake and efflux in macrophages.

Topics: Atherosclerosis; CD36 Antigens; Cholesterol; Foam Cells; Humans; Lipoproteins, LDL; Macrophages; Neuropeptide Y

Topics: Atherosclerosis; Autophagy; Humans; Interleukin-10; Lipopolysaccharides; Macrophage Activation; Macrophages; Neuropeptide Y; NF-E2-Related Factor 2; Sequestosome-1 Protein

Several large clinical trials have confirmed the cardioprotective role of sodium-glucose cotransporter 2 inhibitors (SGLT2i) in patients with type 2 diabetes. However, whether empagliflozin, as an SGLT2i, could alleviate atherosclerosis progression in non-diabetic states remain unknown.. ApoE-/- mice were fed a Western diet for 12 weeks to induce atherosclerosis. On the 7th week, a group of mice were treated with drinking water containing empagliflozin (10 mg/kg/day), while another group was given normal water. At the 12th week, the whole aortas of each group were harvested. Oil Red O, HE and Movat staining were performed for atherosclerotic lesion area and size. Mouse serum lipid profiles (total cholesterol [TC], triglyceride [TG], low-density lipoprotein-c [LDL], and high-density lipoprotein-c [HDL]), systemic inflammation levels (IL-1β, IL-6 and IL-10), renin-angiotensin-aldosterone system (RAAS) components and sympathetic activity (norepinephrine and neuropeptide Y) indicators were measured by ELISA.. Empagliflozin reduced the atherosclerotic lesion burden (-8.6 %, P = 0.004) at aortic root in ApoE-/- mice. In addition, empagliflozin decreased body weight (-3.27 g, P = 0.002), lipid profiles (TC: [-15.3 mmol/L, P = 0.011]; TG: [-2.4 mmol/L, P < 0.001]; LDL: [-2.9 mmol/L, P = 0.010]), RAAS (renin [-9.3 ng/L, P = 0.047]; aldosterone [-16.7 ng/L, P < 0.001]) and sympathetic activity (norepinephrine [-8.9 ng/L, P = 0.019]; neuropeptide Y [-8.8 ng/L, P = 0.002]). However, the anti-inflammatory effect of empagliflozin was not significantly evident.. The early atherosclerotic lesion size was less visible in empagliflozin-treated mice. Empagliflozin could decrease lipid profiles and sympathetic activity in atherosclerosis.

Topics: Animals; Atherosclerosis; Benzhydryl Compounds; Body Weight; Disease Progression; Glucosides; Inflammation; Lipids; Male; Mice; Neuropeptide Y; Norepinephrine; Renin-Angiotensin System; Sodium-Glucose Transporter 2 Inhibitors; Sympathetic Nervous System

Population-based studies have shown that exercise has anti-atherosclerotic effects, but the mechanisms underlying this cardiac protection are poorly understood. The aim of this study was to investigate if the anti-atherosclerotic effects of exercise are associated with changes in neuropeptide Y (NPY) expression in apolipoprotein E-deficient (ApoE. Eight weeks of occasional exercise was equally effective as regular exercise at preventing atherosclerotic plaque formation and enhancing atherosclerotic plaque stability. This was shown by increased plaque collagen and smooth muscle cell content and decreased plaque lipid and macrophage content. The expression of NPY and its receptors in the vasculature was decreased in the regular exercise and occasional exercise groups, and this expression was significantly correlated with the progress of atherosclerosis. Moreover, exercise may reduce the activity of macrophages by down-regulating the expression of NPY Y1 receptors, thereby reducing the release of inflammatory cytokines.. These results suggest that exercise training can attenuate plaque burden and enhance atherosclerotic plaque stability. The anti-atherosclerotic effect of exercise appears to be, at least in part, dependent on down-regulation of the expression of NPY and its receptors (especially Y1 receptors) in the aorta.

Topics: Animals; Aorta; Apolipoproteins E; Atherosclerosis; Cytokines; Disease Models, Animal; Gene Expression Regulation; Inflammation; Male; Mice; Mice, Inbred C57BL; Mice, Knockout, ApoE; Myocytes, Smooth Muscle; Neuropeptide Y; Physical Conditioning, Animal

Endothelial dysfunction has been linked to vascular inflammation and foam cell formation but the underlying mechanisms still remain unclear. We sought to define the factors inducing inflammation and smooth muscle foam cell formation under endothelial dysfunction using endothelial nitric oxide synthase (eNOS)-deficient mice. Vascular smooth muscle cells (VSMCs) from eNOS-deficient mice displayed increased expression of macrophage-related genes and elevated lipid uptake. Neuropeptide Y (NPY) was upregulated in the aorta from the eNOS-deficient mice and promoted macrophage chemotaxis toward VSMCs while enhancing the activity of matrix metalloproteinase-3. Notably, NPY induced lipid uptake in VSMCs, facilitating smooth muscle foam cell formation, in association with enhanced expression of genes related to modified low-density lipoprotein uptake and macrophages. NPY was augmented by inflammatory pentraxin 3 (PTX3) in VSMCs. PTX3 enhanced macrophage migratory capacity through the NPY/neuropeptide Y receptor axis and this effect was attenuated by pharmacological inhibition with a receptor-specific antagonist. These observations suggest that endothelial dysfunction leads to the elevation of NPY that amplifies vascular inflammation by increasing inflammatory cell chemotaxis and triggers smooth muscle foam cell formation.

Topics: Animals; Atherosclerosis; C-Reactive Protein; Chemotaxis, Leukocyte; Endothelium, Vascular; Foam Cells; Macrophages; Mice; Mice, Knockout; Muscle, Smooth, Vascular; Myocytes, Smooth Muscle; Nerve Tissue Proteins; Neuropeptide Y; Nitric Oxide Synthase Type III; Plaque, Atherosclerotic

The proliferation-promoting effect of neuropeptide Y (NPY) always functions in low-serum-cultured vascular smooth muscle cells (VSMCs), and the phenotypic switch of VSMCs is regulated by concentrations of serum. Whether the property of the NPY proliferative effect in VSMCs relies on phenotype of VSMCs is unclear. We aimed to explore the role of NPY on proliferation of different VSMC phenotypes in the pathogenesis of atherosclerosis. By stimulating A10 cells with 200 nM NPY in 0.5 or 10% serum, 3H-thymidine and 5-ethynyl-2'-deoxyuridine (EdU) and CCK8 measurements were used to detect VSMC proliferation. RT-PCR and Flow cytometry were performed to detect the factors involved in different properties of the NPY proliferative effect in VSMCs. Instead of facilitating proliferation, NPY had no significant effect on the growth of VSMCs when cultured in 10% serum (VSMCs stayed at synthetic states). The underlying mechanism may be involved in down-regulation of Y1 receptor (P < 0.05 vs. Vehicle) and up-regulation of Geminin (P < 0.05 vs. Vehicle) in 10% serum-cultured VSMCs co-incubated with 200 nM NPY. Besides, modulation of Geminin was effectively blocked by the Y1 receptor antagonist. The stimulation of NPY on proliferation of VSMCs could be a double-edged sword in the development of atherosclerosis and thus provides new knowledge for therapy of atherosclerosis.

Topics: Animals; Atherosclerosis; Cell Line; Cell Proliferation; Geminin; Muscle, Smooth, Vascular; Myocytes, Smooth Muscle; Neuropeptide Y; Rats

Proliferation of vascular smooth muscle cells (VSMCs) is thought to have a key role in the development of atherosclerotic lesions. Neuropeptide Y (NPY), norepinephrine and dopamine are sympathetic neurotransmitters. NPY has been particularly shown to stimulate proliferation of VSMCs. NPY, norepinephrine and dopamine are all sympathetic transmitters. In our previous study, we found that in the presence of the dopamine receptor, the α1-adrenergic receptor-mediated VSMC proliferation is reduced. We hypothesize that the activation of the D1-like receptor might inhibit the NPY-mediated VSMC proliferation. In our present study, we found that NPY, mainly via the Y1 receptor, increased VSMC proliferation. This was determined by [(3)H]-thymidine incorporation, in a concentration (10(-11) to 10(-8)  M)-dependent manner. In the presence of the D1-like receptor agonist, fenoldopam (10(-12) to 10(-5) M), the stimulatory effect of NPY on VSMC proliferation was reduced. The involvement of the D1-like receptor was confirmed when the inhibitory effect of fenoldopam was reversed in the presence of the D1-like receptor antagonist SCH-23390 (10(-8) M). Moreover, the inhibitory effect of fenoldopam on NPY-mediated VSMC proliferation was also blocked in the presence of the PKA inhibitor 14-22 (10(-6)  M). Protein kinase A activator 8-(4-chlorophenylthio) adenosine-3,5-cyclic monophosphorothioate, Sp-isomer sodium salt (10(-6)  M) could simulate the stimulatory effect of fenoldopam. It indicated that the inhibitory effect of D1-like receptors on NPY-mediated VSMC proliferation may have an important role in the regulation of blood pressure or prevention of atherosclerosis.

Topics: Animals; Atherosclerosis; Cell Proliferation; Cyclic AMP-Dependent Protein Kinases; Fenoldopam; Male; Muscle, Smooth, Vascular; Myocytes, Smooth Muscle; Neointima; Neuropeptide Y; Rats; Rats, Sprague-Dawley; Receptors, Dopamine D1

Chronic methamphetamine (METH) abuse could induce neurotoxicity due to reactive oxygen species generation and sympathetic activation. Both factors are associated with atherosclerosis, so we tested the hypothesis that chronic METH administration might also promote atherosclerosis formation in Apo E-/- knockout mice fed normal diet.. Male ApoE-/- mice (6 weeks-old) were treated with saline (NS) or METH [4 mg/kg/day (M4) or 8 mg/kg/day (M8) through intraperitoneal injection] for 24 weeks. Atherosclerotic lesion area on oil red O stained en face aorta was dose-dependently increased in M4 and M8 groups compared to NS group. Percentage of atherosclerotic lesion area was significantly higher in M8 group compared to NS and M4 groups. Plasma CRP was increased and inflammatory cytokine (ICAM-1, VCAM-1, TNF-α, and INF-γ) expression on aortic root was upregulated in METH groups compared to NS group. Neuropeptide Y (NPY) protein and mRNA expressions in aortic root and myocardial tissue were determined by Western blot and real time PCR, which were significantly upregulated in M4 and M8 groups. Moreover, mRNA expressions of NPY1R, NPY2R and NPY5R in aortic and myocardial tissue were also significantly upregulated in M4 and M8 groups. Raw264.7 cells were treated with NPY, NPY receptor antagonists, METH (10 μM or 100 μM) with or without lipopolysaccharide (LPS), and the expressions of TNF-α, CRP, MCP-1 and reactive oxygen species (ROS) production were significantly increased in METH and LPS + METH groups compared to control and LPS groups. Co-treatment with NPY1R antagonist decreased the expressions of TNF-α, CRP and MCP-1 in NPY and METH treated cells.. Chronic METH administration can promote inflammation and atherosclerotic plague formation in ApoE-/- mice fed normal chow. NPY might be involved in the pathogenesis of METH-induced atherogenic effects through NPY Y1 receptor pathway.

Topics: Animal Feed; Animals; Aorta; Apolipoproteins E; Atherosclerosis; Body Weight; C-Reactive Protein; Cell Line; Enzyme-Linked Immunosorbent Assay; Heart; Immunohistochemistry; Inflammation; Macrophages; Male; Methamphetamine; Mice; Mice, Inbred C57BL; Mice, Knockout; Myocardium; Neuropeptide Y; Reactive Oxygen Species; Real-Time Polymerase Chain Reaction; Sympathomimetics; Tumor Necrosis Factor-alpha

Neuropeptide Y is an abundantly expressed neurotransmitter capable of modulating both immune and metabolic responses related to the development of atherosclerosis. NPY receptors are expressed by a number of vascular wall cell types, among which mast cells. However, the direct effects of NPY on atherosclerotic plaque development and progression remain to be investigated. In this study we thus aimed to determine whether NPY is expressed in atherosclerotic plaques and to establish its role in atherosclerotic plaque development.. NPY expression was seen to be increased up to 2-fold in unstable human endarterectomy plaques, as compared to stable plaques, and to be significantly upregulated during lesion progression in apoE(-/-) mice. In apoE(-/-) mice focal overexpression of NPY in the carotid artery significantly increased atherosclerotic plaque size compared to controls, while plaque composition was unaffected. Interestingly, perivascular mast cell activation was significantly higher in the NPY-overexpressing mice, suggesting that NPY may impact plaque progression in part via mast cell activation. Furthermore, in vitro NPY-induced murine mast cell activation resulted in the release of pro-atherogenic mediators including IL-6 and tryptase.. Our data show that NPY expression is increased during atherogenesis and in particular in unstable plaques. Furthermore, perivascular overexpression of NPY promoted plaque development and perivascular mast cell activation, suggestive of a role for NPY-induced mast cell activation in lesion progression.

Topics: Animals; Apolipoproteins E; Atherosclerosis; Disease Progression; Gene Expression Profiling; Gene Expression Regulation; HEK293 Cells; Humans; Immunohistochemistry; Inflammation; Interleukin-6; Lentivirus; Mast Cells; Mice; Mice, Knockout; Muscle, Smooth, Vascular; Neuropeptide Y; Plaque, Atherosclerotic; Tryptases

The primary purpose of this investigation was to determine whether ApoE(-/-) mice, when subjected to chronic stress, exhibit lesions characteristic of human vulnerable plaque and, if so, to determine the time course of such changes. We found that the lesions were remarkably similar to human vulnerable plaque, and that the time course of lesion progression raised interesting insights into the process of plaque development. Lard-fed mixed-background ApoE(-/-) mice exposed to chronic stress develop lesions with large necrotic core, thin fibrous cap and a high degree of inflammation. Neovascularization and intraplaque hemorrhage are observed in over 80% of stressed animals at 20 weeks of age. Previously described models report a prevalence of only 13% for neovascularization observed at a much later time point, between 36 and 60 weeks of age. Thus, our new stress-induced model of advanced atherosclerotic plaque provides an improvement over what is currently available. This model offers a tool to further investigate progression of plaque phenotype to a more vulnerable phenotype in humans. Our findings also suggest a possible use of this stress-induced model to determine whether therapeutic interventions have effects not only on plaque burden, but also, and importantly, on plaque vulnerability.

Topics: Animals; Atherosclerosis; Blood Pressure; Cholesterol; Coronary Stenosis; Corticosterone; Disease Models, Animal; Hemorrhage; Humans; Inflammation; Mice; Mice, Inbred C57BL; Necrosis; Neovascularization, Pathologic; Neuropeptide Y; Plaque, Atherosclerotic; Stress, Psychological

The role of neuropeptide Y (NPY) and its gene polymorphisms in the development of atherosclerosis has become increasingly evident. In asthma, NPY has been shown to be involved as immunomodulator. In this study, we investigated the role of two functional NPY polymorphisms, NPY-Leu7Pro (rs16139) and NPY-399C/T (rs16147) and obesity for the development of asthma as well as atherosclerosis in asthmatic and non-asthmatic subjects. Also, we measured heart rate variability (HRV) and NPY in serum since these might contribute through these polymorphisms to both diseases.. Thousand hundred and seventy six Finnish young adults were genotyped and three groups (G1-G3) were formed based on the observed diplotypes. The NPY-Pro7 allele always co-existed with the NPY-399T allele indicating complete linkage disequilibrium. Here we show that overweight (BMI≥25kg/m2) was associated with 2.5-fold increased risk for asthma in subjects with the NPY-399T allele without NPY-Pro7 allele (G2, n=716). Overweight was also associated with increased atherosclerosis determined by carotid intima media thickness (cIMT), but asthma seemed to be more significant determinant than overweight in determing cIMT having a decreasing effect. NPY concentration in serum was diplotype-driven (G1=792.2(29.5), G2=849.0(18.9), G3=873.9(45.2) pg/ml) and correlated positively with cIMT in the group having NPY-Pro7 allele (G3, n=142). However, the subjects with asthma had a negative NPY-cIMT relationship. Total HRV was increased in asthma and correlated negatively with cIMT irrespective of the NPY genotype.. Overweight together with the NPY-399T allele without NPY-Pro7 allele was associated with increased risk for asthma. Atherosclerosis was decreased in subjects with asthma depending on the NPY genotype. The results reveal novel insights into the genetics and biology of the relationship of atherosclerosis and asthma.

Topics: Adolescent; Alleles; Anthropometry; Asthma; Atherosclerosis; Body Height; Body Weight; Carotid Intima-Media Thickness; Child; Child, Preschool; Cohort Studies; Data Interpretation, Statistical; DNA; Endothelium, Vascular; Female; Finland; Gene Frequency; Genotype; Heart Rate; Humans; Lipids; Male; Neuropeptide Y; Overweight; Polymorphism, Genetic; Risk

Neuropeptide Y (NPY), a sympathetic and platelet-derived vascular mitogen and angiogenic factor, has been implicated in atherosclerosis in animal and human genetic studies. Here we evaluate its association with human and murine atherosclerosis, and assess the role of platelet-derived NPY in lesion vulnerability. NPY immunoreactivity (NPY-ir) was measured in the platelet-poor and platelet-rich (PRP) plasmas, and NPY receptors (mitogenic Y1R and angiogenic Y2 and Y5Rs), CD26/DPPIV (a protease forming Y2/Y5-selective agonist), CD31-positive vascularity, and lesion morphology assessed by histo- and immunocyto-chemistry-in patients with peripheral artery disease (PAD) and healthy volunteers, and in lard-fed ApoE-/- mice. NPY and NPY-R immunostaining was greater in lesions from PAD patients compared to normal vessels of healthy volunteers (p < 0.001), and localized to smooth muscle cells, macrophages, and adventitial/neovascular endothelial cells. CD26/DPPIV staining co-localized with CD31-positive endothelial cells only in atherosclerotic lesions. NPY-ir in PRP (but not plasma) and vascular immunostaining was higher (p < 0.05 and 0.001, respectively) in men (not women) with PAD compared to healthy subjects. A similar gender specificity was observed in mice. PRP NPY-ir levels correlated with lesion area (p = 0.03), necrotic core area, and the necrotic core-to-lesion area ratio (p < 0.01) in male, but not female, mice. Also males with neovascularized lesions had higher PRP NPY-ir levels than those lacking lesion microvessels (p < 0.05). NPY and its Rs are up-regulated in human and murine atherosclerotic lesions suggesting pathogenic role. DPPIV expression by microvascular endothelium in atherosclerotic tissue may shift NPY's affinity toward angiogenic Y2/Y5Rs, and thus enhance angiogenesis and lesion vulnerability. Remarkably, plaque neovascularization was associated with increased NPY-ir in PRP in males but not females, suggesting that platelet NPY may be a novel mediator/marker of lesion vulnerability particularly in males, for reasons that remain to be determined. Both animal and human data suggest that NPY is an important contributor to, and platelet NPY-ir a marker of, atherosclerotic lesion burden and vulnerability but only in males, perhaps due to androgen-dependent up-regulation of NPY, previously shown in rats.

Topics: Adult; Aged; Analysis of Variance; Animals; Apolipoproteins E; Arteries; Atherosclerosis; Blood Platelets; Case-Control Studies; Dipeptidyl Peptidase 4; Disease Models, Animal; Female; Humans; Immunohistochemistry; Linear Models; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Middle Aged; Neovascularization, Pathologic; Neuropeptide Y; Peripheral Arterial Disease; Platelet Endothelial Cell Adhesion Molecule-1; Polymerase Chain Reaction; Receptors, Neuropeptide Y; Severity of Illness Index; Sex Factors; Up-Regulation; Young Adult

Inflammation and stress are regarded as two important atherogenic factors. Because stress can affect leukocyte distribution, we hypothesized that stress-mediated leukocyte extravasation can modify the inflammatory environment of the arterial wall possibly contributing to atherogenesis. To test this hypothesis we evaluated the inflammatory environment of the aorta in C57Bl/6 mice subjected to 3 and 12 months of chronic stress and compared it to age matched non-stressed animals. Experiments were carried out in mice fed regular chow or atherogenic diets. Both treatments increased the expression of vascular and leukocyte adhesion molecules and leukocyte accumulation. At 3 months, stress but not an atherogenic diet elevated the number of CD4 cells, CD8 cells, macrophages, dendritic cells and neutrophils. These changes were associated with elevation of transcripts for ICAM-1 and VCAM-1, E-selectin and neuropeptide Y. At 12 months, stress or high cholesterol acted similarly to elevate the number of CD8 and macrophages, and synergistically on the number of all cell types investigated. At this time-point, strong synergism was also observed on the level of E-selectin and NPY in the aorta, but not in the circulation. Despite these effects, histological and morphological alterations of the arterial wall were severe in the atherogenic diet, but not in the stress groups. Thus, although stress and an atherogenic diet may both affect leukocyte accumulation in the aorta, they may contribute differently to atherogenesis.

Topics: Animals; Aorta; Atherosclerosis; Biomarkers; Chronic Disease; Diet; Diet, Atherogenic; E-Selectin; Enzyme-Linked Immunosorbent Assay; Flow Cytometry; Immunoenzyme Techniques; Immunohistochemistry; Inflammation; Intercellular Adhesion Molecule-1; Leukocyte Count; Male; Mice; Mice, Inbred C57BL; Neuropeptide Y; Plaque, Atherosclerotic; Real-Time Polymerase Chain Reaction; Stress, Psychological; Vascular Cell Adhesion Molecule-1

The Leucine7 to Proline7 (Leu7Pro) polymorphism of the signal peptide of neuropeptide Y (NPY) increases risk for vascular complications in diabetes. Diabetes is associated with low-grade inflammation, which has an important role in the development of atherosclerosis. Currently, we followed diabetes patients to investigate, if the Pro7 allele is associated with the inflammation related to atherosclerosis.. In the 5-year follow-up, the genotyped, pair-matched type 2 diabetes patients (12 with the Pro7 allele and 19 without) were investigated using non-invasive ultrasound based methods to measure the development of atherosclerosis (intima media thickness=IMT) and endothelium-dependent (FMD) and -independent nitrate-mediated (NMD) vasodilatation. The development of diabetic complications was followed annually, and the concentrations of inflammatory markers and NPY in plasma were determined.. Patients with the Pro7 had increased U-albumin/creatinine (p=0.037), E-selectin (p=0.016), fasting insulin (p=0.011) and HOMA index (p=0.013) but decreased serum amyloid P concentrations (p=0.021). Furthermore, men with the Pro7 had increased CRP (p=0.010) and NPY (p=0.026) concentrations. IMT and FMD were similar in all patients, however, NMD decreased more during the follow-up in the patients with the Pro7 (p=0.002). NPY correlated positively with bIMT [r 0.04 (SE 0.02), p=0.007] and E-selectin negatively with FMD [r -0.05 (S.E 0.02), p=0.039].. Diabetes patients with the Pro7 allele display increased levels of inflammatory molecules and NPY in blood, preceding vascular wall thickening and impaired endothelial dilatation, especially in male patients.

Topics: Aged; Albuminuria; Atherosclerosis; Biomarkers; C-Reactive Protein; Creatinine; Diabetes Mellitus, Type 2; Diabetic Angiopathies; E-Selectin; Female; Finland; Follow-Up Studies; Genetic Predisposition to Disease; Humans; Inflammation Mediators; Insulin Resistance; Linear Models; Logistic Models; Male; Matched-Pair Analysis; Middle Aged; Neuropeptide Y; Phenotype; Plasminogen Activator Inhibitor 1; Polymorphism, Genetic; Protein Sorting Signals; Risk Assessment; Risk Factors; Serum Amyloid P-Component; Sex Factors; Time Factors; Ultrasonography; Up-Regulation; Vasodilation

Neuropeptide Y (NPY) is a strong candidate gene for coronary artery disease (CAD). We have previously identified genetic linkage to familial CAD in the genomic region of NPY. We performed follow-up genetic, biostatistical, and functional analysis of NPY in early-onset CAD. In familial CAD (GENECARD, N = 420 families), we found increased microsatellite linkage to chromosome 7p14 (OSA LOD = 4.2, p = 0.004) in 97 earliest age-of-onset families. Tagged NPY SNPs demonstrated linkage to CAD of a 6-SNP block (LOD = 1.58-2.72), family-based association of this block with CAD (p = 0.02), and stronger linkage to CAD in the earliest age-of-onset families. Association of this 6-SNP block with CAD was validated in: (a) 556 non-familial early-onset CAD cases and 256 controls (OR 1.46-1.65, p = 0.01-0.05), showing stronger association in youngest cases (OR 1.84-2.20, p = 0.0004-0.09); and (b) GENECARD probands versus non-familial controls (OR 1.79-2.06, p = 0.003-0.02). A promoter SNP (rs16147) within this 6-SNP block was associated with higher plasma NPY levels (p = 0.04). To assess a causal role of NPY in atherosclerosis, we applied the NPY1-receptor-antagonist BIBP-3226 adventitially to endothelium-denuded carotid arteries of apolipoprotein E-deficient mice; treatment reduced atherosclerotic neointimal area by 50% (p = 0.03). Thus, NPY variants associate with atherosclerosis in two independent datasets (with strong age-of-onset effects) and show allele-specific expression with NPY levels, while NPY receptor antagonism reduces atherosclerosis in mice. We conclude that NPY contributes to atherosclerosis pathogenesis.

Topics: Age of Onset; Alleles; Animals; Arginine; Atherosclerosis; Female; Genetic Predisposition to Disease; Genotype; Humans; Linkage Disequilibrium; Lod Score; Male; Mice; Mice, Transgenic; Middle Aged; Neuropeptide Y; Polymorphism, Genetic; Receptors, Neuropeptide Y