Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0004153 (atherosclerosis)
 77,401 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Lysophosphatidic acid (LPA) and sphingosine 1-phosphate (S1P) are both low-molecular-weight lysophospholipid (LPL) ligands which are recognized by the Edg family of G protein-coupled receptors (GPCRs). In endothelial cells, these two ligands activate Edg receptors resulting in cell proliferation and cell migration. Interleukin-8 (IL-8) is a C-X-C chemokine and acts as a chemoattractant of neutrophils, whereas monocyte chemoattractant protein-1 (MCP-1) is a C-C chemokine and functions mainly as a chemoattractant of monocytes/macrophages. Both factors are secreted from endothelial cells and have been implicated in the processes leading to atherosclerosis. We examined the effects of LPLs on the expression of IL-8 and MCP-1, key regulators of leukocyte recruitment in human umbilical cord vein endothelial cells (HUVECs). Work illustrated in this article showed that LPA and S1P enhanced IL-8 and MCP-1 mRNA expressions, and protein secretions in dose- and time-dependent fashions. Maximal mRNA expression appeared at 16 hr post-ligand treatment. Using prior treatments with chemical inhibitors, LPLs enhanced IL-8 and MCP-1 expressions through a Gi-, Rho-, and NFkappaB-dependent mechanism. In a chemotaxis assay system, LPL treatments of endothelial cells enhanced monocyte recruitment through upregulating IL-8 and MCP-1 protein secretions. Pre-incubation with AF12198, an IL-1 receptor antagonist or IL-1 functional blocking antibody both suppressed the enhanced effects elicited by LPLs of IL-8 and MCP-1 mRNA expressions in HUVECs. These results suggest that LPLs released by activated platelets might enhance the IL-8- and MCP-1-dependent chemoattraction of monocytes toward the endothelium through an IL-1-dependent mechanism, which may play an important role in facilitating wound-healing and inflammation processes.
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PMID:Lysophospholipids increase IL-8 and MCP-1 expressions in human umbilical cord vein endothelial cells through an IL-1-dependent mechanism. 1679 34

Community-based studies and surveys have found an association between lower urinary tract symptoms (LUTS) and sexual dysfunction, in particular, erectile dysfunction (ED). The link between ED and LUTS has biologic plausibility. The following 4 theories have been used to explain how these disorders interrelate: 1) decreased or altered nitric oxide synthase/nitric oxide levels in the prostate and penile smooth muscle; 2) autonomic hyperactivity effects on LUTS, prostate growth, and ED; 3) increased Rho-kinase activation/endothelin activity; and 4) prostate and penile atherosclerosis. The relationship of LUTS and sexual dysfunction suggests that treatment of one condition may impact the other.
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PMID:Sexual Function and alpha-Blockers. 1698 88

Investigations from basic biology suggest that activation of the Rho/Rho kinase pathway reduces the bioavailability of nitric oxide (NO) and thereby promotes atherosclerosis and its clinical complications. Yet, little information is available about the relationship of the Rho/Rho kinase pathway to NO bioavailability in humans with atherosclerosis. Accordingly, we determined whether inhibition of Rho kinase augments NO bioavailability and improves endothelial function in human subjects with coronary artery disease (CAD). Thirteen CAD subjects and 16 age- and sex-matched healthy controls were randomly assigned to receive the Rho kinase inhibitor, fasudil, or placebo for 1 month each in a double-blind crossover trial. Flow-mediated, endothelium-dependent and nitroglycerin-induced, endothelium-independent vasodilation were assessed by brachial artery ultrasonography. Rho kinase activity was measured in peripheral leukocytes. Fasudil increased endothelium-dependent vasodilation in CAD subjects from 9.4+/-1.9% to 13.4+/-1.9% (P=0.001) but not in healthy controls (from 11.3+/-1.4% to 7.7+/-1.1%; P=0.07). Endothelium-independent vasodilation was not affected by fasudil in either CAD or healthy subjects. Fasudil reduced Rho kinase activity by 59+/-18% in CAD subjects (P=0.001) but not in healthy subjects (by 3+/-6%; P=0.60). The change in endothelium-dependent vasodilation achieved with fasudil relative to placebo was inversely proportional to Rho kinase inhibition (ie, greater Rho kinase inhibition was associated with larger improvement in endothelium-dependent vasodilation) (r=-0.48; P=0.01). These findings suggest that Rho/Rho kinase activation promotes endothelial dysfunction in humans with atherosclerosis. Inhibition of the Rho/Rho kinase pathway should provide a useful strategy to restore NO bioavailability in humans with atherosclerosis.
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PMID:Rho kinase inhibition improves endothelial function in human subjects with coronary artery disease. 1709 25

Statins, the most widely prescribed cholesterol-lowering drugs, are considered to be first-line therapeutics for the prevention of coronary heart disease and atherosclerosis. Statins act by inhibiting the enzyme 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) reductase, the rate-limiting enzyme in endogenous cholesterol biosynthesis, which catalyzes the reduction of HMG-CoA to mevalonic acid. Inhibition of this enzyme has proven to be effective for lowering plasma total cholesterol, low-density lipoprotein-cholesterol, and triglyceride levels in humans and can therefore be useful to treat atherosclerotic and dyslipidemic disorders. However, the clinical benefits of statins appear to extend beyond their lipid-lowering effects. Besides reducing cholesterol biosynthesis, inhibition of mevalonate by statins also leads to a reduction in the synthesis of important intermediates, such as the isoprenoids farnesyl pyrophosphate and geranylgeranyl pyrophosphate. These intermediates are involved in the posttranslational prenylation of several proteins (e.g., Ras, Rho, Rac) that modulate a variety of cellular processes including cellular signaling, differentiation, and proliferation. Given the central role of these isoprenylated proteins in endothelial function, atherosclerotic plaque stability, platelet activity, coagulation, oxidation, and inflammatory and immunologic responses, it could be anticipated that these compounds may exert multiple beneficial effects in a broad spectrum of disorders including cardiovascular disease, osteoporosis, Alzheimer's disease and related vascular dementia, viral and bacterial infection, etc. This article summarizes these cholesterol-lowering-independent effects of statins, termed "pleiotropic effects", and the underlying mechanisms, as well as the preclinical experimental approaches that would be useful to evaluate the effects of statins.
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PMID:Pleiotropic effects of statins and related pharmacological experimental approaches. 1747 99

RhoA/Rho-kinase signaling and its relationship/balance with the nitric oxide level, angiotensin II and vasopressors for cardiovascular pathophysiology is of increasing importance, and its involvement goes far beyond blood pressure regulation. The deep involvement of this pathway in cardiovascular biology is now known to include a wide spectrum of conditions relating to the long-term complications of hypertension, and in general of cardiovascular pathophysiology, such as changes in cardiovascular structure (remodeling) and the induction of atherosclerosis, involvement in the pathophysiological relationships between inflammation and hypertension, and in those between hypertension, glucose metabolism and insulin resistance. Studies from our laboratory have made an important contribution to the understanding of the cellular and molecular mechanisms mediated by the RhoA/Rho-kinase pathway, which include all the aspects of cardiovascular pathophysiology in which this pathway plays a role. In addition, if it is considered that our contribution to the clarification of these mechanisms only comes from studies in humans, their impact on the scenario of the RhoA/Rho-kinase pathway's biology, essentially supported by studies 'in vitro' or in animal models, is immediate. This review examines all the aspects of RhoA/Rho-kinase signaling in the light of the available data, and gives an updated and useful overall picture of its involvement in cardiovascular pathophysiology.
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PMID:RhoA/Rho-kinase pathway: much more than just a modulation of vascular tone. Evidence from studies in humans. 1721 Dec 28

Human umbilical vein endothelial cells (HUVECs) have played a major role as a model system for the study of the regulation of endothelial cell function and the role of the endothelium in the response of the blood vessel wall to stretch, shear forces, and the development of atherosclerotic plaques and angiogenesis. Here, we use HUVECs and human microvascular endothelial cells to study the role of the HMG-CoA reductase inhibitor, simvastatin, and the small GTP-binding protein Rho in the regulation of angiogenesis. Simvastatin inhibited angiogenesis in response to FGF-2 in the corneal pocket assay of the mouse and in vascular endothelial growth factor (VEGF)-stimulated angiogenesis in the chick chorioallontoic membrane. Furthermore, simvastatin inhibited VEGF-stimulated tube formation by human dermal microvascular endothelial cells and the formation of honeycomb-like structures by HUVECs. The effect was dose-dependent and was not secondary to apoptosis. Geranylgeranyl-pyrophosphate (GGPP), a product of the cholesterol metabolic pathway that serves as a substrate for the posttranslational lipidation of RhoA, was required for membrane localization, but not farnesylpyrophosphate (FPP), the substrate for the lipidation of Ras. Furthermore, GGTI, a specific inhibitor of GGPP, mimicked the effect of simvastatin of tube formation and the formation of honeycombs whereas FTI, a specific inhibitor of the farnesylation of Ras, had no effect. Adenoviral expression of a DN-RhoA mutant mimicked the effect of simvastatin on tube formation and the formation of honeycombs, whereas a dominant activating mutant of RhoA reversed the effect of simvastatin on tube formation. Finally, simvastatin interfered with the membrane localization of RhoA with a dose-dependence similar to that for the inhibition of tube formation. Simvastatin also inhibited the VEGFstimulated phosphorylation of the VEGF receptor KDR, and the tyrosine kinase FAK, which plays a role in cell migration. These data demonstrate that simvastatin interfered with angiogenesis via the inhibition of RhoA. Data supporting a role for angiogenesis in the development and growth of atherosclerotic plaques suggest that this antiangiogenic effect of Statins might prevent the progression of atherosclerosis via the inhibition of plaque angiogenesis.
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PMID:Human umbilical vein endothelial cells and human dermal microvascular endothelial cells offer new insights into the relationship between lipid metabolism and angiogenesis. 1723 47

Atherosclerosis and its complications represent the major cause of death in developed countries. Statins are inhibitors of 3-hydroxy-3-methylglutaryl coenzyme A [HMGCoA] reductase and consequently inhibitors of cholesterol biosynthesis. Statins have been described as the most potent class of drugs to reduce serum cholesterol levels. In clinical trials, statins are beneficial in primary and secondary prevention of coronary heart disease. Statins, were initially designed as cholesterol-lowering drugs. However, these drugs, besides their lipid-lowering properties, exert a number of protective effects on the cardiovascular system that emerged over the past years. The benefits observed with statin treatment appear to be greater than that might be expected from reduction in lipid levels alone, suggesting effects beyond cholesterol lowering. These cholesterol-independent effects have been called "pleiotropic". The cholesterol-independent or "pleiotropic" effects of statins involve improvement of endothelial function, stability of atherosclerotic plaques, decrease of oxidative stress and inflammation, and inhibition of thrombogenic response. These pleiotropic effects of statins have been proposed as key properties of these drugs to reduce cardiovascular morbidity and mortality. The present review will emphasize the molecular mechanisms underlying the effects of statins on endothelial function and oxidative stress. In particular, inhibition of small GTP-binding proteins, Rho, Ras and Rac, which are regulated by isoprenoids [farnesyl pyrophosphate and geranylgeranyl pyrophosphate], seems to play an important role in mediating the pleiotropic effects of statins.
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PMID:Endothelial dysfunction, oxidative stress and inflammation in atherosclerosis: beneficial effects of statins. 1726 83

Recently, it has become evident that elevated levels of plasminogen activator inhibitor-1 (PAI-1) are associated with myocardial infarction and stroke, especially in patients with diabetes. The molecular mechanisms involved in hyperglycemia-induced PAI-1 expression in bovine aortic endothelial cells (BAEC) were investigated. PAI-1 expression in BAEC was significantly increased in accordance with the concentration of glucose in media from 5.7 mM to 23 mM. Stimulation with high glucose (23 mM) significantly increased small GTPase Rho A activation. Pretreatment with a Rho-kinase inhibitor, Y-27632 (1-10 microM), significantly blocked high glucose-induced PAI-1 expression. NF-kappaB activity determined using the luciferase reporter gene assay was significantly enhanced by high glucose, and pretreatment with Y-27632 inhibited high glucose-induced PAI-1 expression at the basal level. An inhibitor of NF-kappaB action, namely parthenolide (0.1 microM), BAY 11-7082 (5 microM) and SN50 (1 microM), significantly blocked high glucose-mediated PAI-1 expression to a level with low glucose (5.7 mM). These data suggested that high glucose-induced PAI-1 expression in endothelial cells is mediated by NF-kappaB activation through the Rho/Rho-kinase pathway. Inhibition of Rho/Rho-kinase signaling might be a novel target for diabetes and metabolic syndrome.
Atherosclerosis 2008 Jan
PMID:High glucose induces plasminogen activator inhibitor-1 expression through Rho/Rho-kinase-mediated NF-kappaB activation in bovine aortic endothelial cells. 1727 7

Increased tissue or serum levels of oxidized phospholipids have been detected in a variety of chronic and acute pathological conditions such as hyperlipidemia, atherosclerosis, heart attack, cell apoptosis, acute inflammation and injury. We have recently described signaling cascades activated by oxidized 1-palmitoyl-2-arachidonoyl-sn-glycero-3-phosphocholine (OxPAPC)in the human pulmonary artery endothelial cells (EC) and reported potent barrier-protective effects of OxPAPC, which were mediated by small GTPases Rac and Cdc42. In this study we have further characterized signal transduction pathways involved in the OxPAPC-mediated endothelial barrier protection. Inhibitors of small GTPases, protein kinase A (PKA), protein kinase C (PKC), Src family kinases and general inhibitors of tyrosine kinases attenuated OxPAPC-induced barrier-protective response and EC cytoskeletal remodeling. In contrast, small GTPase Rho, Rho kinase, Erk-1,2 MAP kinase and p38 MAP kinase and PI3-kinase were not involved in the barrier-protective effects of OxPAPC. Inhibitors of PKA, PKC, tyrosine kinases and small GTPase inhibitor toxin B suppressed OxPAPC-induced Rac activation and decreased phosphorylation of focal adhesion kinase (FAK) and paxillin. Barrier-protective effects of OxPAPC were not reproduced by platelet activating factor (PAF), which at high concentrations induced barrier dysfunction, but were partially attenuated by PAF receptor antagonist A85783. These results demonstrate for the first time upstream signaling cascades involved in the OxPAPC-induced Rac activation, cytoskeletal remodeling and barrier regulation and suggest PAF receptor-independent mechanisms of OxPAPC-mediated endothelial barrier protection.
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PMID:Signaling pathways involved in OxPAPC-induced pulmonary endothelial barrier protection. 1729 25

The intracellular signal transduction of AngII (angiotensin II) has been implicated in cardiovascular diseases, such as hypertension, atherosclerosis and restenosis after injury. AT(1) receptor (AngII type-1 receptor), a G-protein-coupled receptor, mediates most of the physiological and pathophysiological actions of AngII, and this receptor is predominantly expressed in cardiovascular cells, such as VSMCs (vascular smooth muscle cells). AngII activates various signalling molecules, including G-protein-derived second messengers, protein kinases and small G-proteins (Ras, Rho, Rac etc), through the AT(1) receptor leading to vascular remodelling. Growth factor receptors, such as EGFR (epidermal growth factor receptor), have been demonstrated to be 'trans'-activated by the AT(1) receptor in VSMCs to mediate growth and migration. Rho and its effector Rho-kinase/ROCK are also implicated in the pathological cellular actions of AngII in VSMCs. Less is known about the endothelial AngII signalling; however, recent studies suggest the endothelial AngII signalling positively, as well as negatively, regulates the NO (nitric oxide) signalling pathway and, thereby, modulates endothelial dysfunction. Moreover, selective AT(1)-receptor-interacting proteins have recently been identified that potentially regulate AngII signal transduction and their pathogenic functions in the target organs. In this review, we focus our discussion on the recent findings and concepts that suggest the existence of the above-mentioned novel signalling mechanisms whereby AngII mediates the formation of cardiovascular diseases.
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PMID:Angiotensin II signal transduction through the AT1 receptor: novel insights into mechanisms and pathophysiology. 1734 43


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