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

Regulation of vascular smooth muscle cell contractile state is critical for the maintenance of blood vessel tone. Abnormal vascular smooth muscle cell contractility plays an important role in the pathogenesis of hypertension, blood vessel spasm, and atherosclerosis. Myosin phosphatase, the key enzyme controlling myosin light chain dephosphorylation, regulates smooth muscle cell contraction. Vasoconstrictor and vasodilator pathways inhibit and activate myosin phosphatase, respectively. G-protein-coupled receptor agonists can inhibit myosin phosphatase and cause smooth muscle cell contraction by activating RhoA/Rho kinase, whereas NO/cGMP can activate myosin phosphatase and cause smooth muscle cell relaxation by activation of cGMP-dependent protein kinase. We have used yeast two-hybrid screening to identify a 116-kDa human protein that interacts with both myosin phosphatase and RhoA. This myosin phosphatase-RhoA interacting protein, or M-RIP, is highly homologous to murine p116RIP3, is expressed in vascular smooth muscle, and is localized to actin myofilaments. M-RIP binds directly to the myosin binding subunit of myosin phosphatase in vivo in vascular smooth muscle cells by an interaction between coiled-coil and leucine zipper domains in the two proteins. An adjacent domain of M-RIP directly binds RhoA in a nucleotide-independent manner. M-RIP copurifies with RhoA and Rho kinase, colocalizes on actin stress fibers with RhoA and MBS, and is associated with Rho kinase activity in vascular smooth muscle cells. M-RIP can assemble a complex containing both RhoA and MBS, suggesting that M-RIP may play a role in myosin phosphatase regulation by RhoA.
 ...
PMID:Myosin phosphatase-Rho interacting protein. A new member of the myosin phosphatase complex that directly binds RhoA. 1450 64

RhoA and Rho-kinase (ROCK) participate in diverse cellular signaling functions such as smooth muscle contraction, cytoskeleton rearrangement, and cell migration and proliferation. In smooth muscle, ROCK plays an important role in calcium sensitization, an event that controls vascular vessel tone. Recent studies using ROCK inhibitors along with cellular and molecular biology techniques have revealed a pivotal role of this enzyme in many other aspects of cardiovascular function. This review will focus on the current understanding of Rho/ROCK signaling pathways and discuss the use of ROCK inhibitors as therapeutic agents for cardiovascular diseases ranging from hypertension to atherosclerosis.
 ...
PMID:Rho kinase inhibitors as potential therapeutic agents for cardiovascular diseases. 1458 50

3-Hydroxy-3-methyl-glutaryl-CoA (HMG-CoA) reductase inhibitors (statins) are effective in patients with hypercholesterolemia to reduce risk of cardiovascular diseases, because of not only their lowering cholesterol effects but also their pleiotropic effects, such as improvement of endothelial cell dysfunction. On the other hand, statins prevent cell proliferation of various cells, including endothelial cells. We examined effects of all statins available at present on the viability of cultured rat pulmonary vein endothelial cells. Lovastatin, simvastatin, atorvastatin, fluvastatin and cerivastatin, which are hydrophobic statins, markedly reduced cell viability associated with DNA fragmentation, DNA laddering and activation of caspase-3, suggesting apoptotic cell death. Pravastatin, which is a hydrophilic statin, however, did not induce cell apoptosis. Apoptosis induced by hydrophobic statins was associated with activation of apoptosis-related intracellular signal transduction systems; attenuation of localization of RhoA to the membrane, induction of Rac1, and increase in phosphorylation of c-Jun N-terminal kinase and c-Jun. Endothelial cell apoptosis is underlying the improvement of the endothelial dysfunction with hydrophobic statins.
Atherosclerosis 2003 Oct
PMID:All hydrophobic HMG-CoA reductase inhibitors induce apoptotic death in rat pulmonary vein endothelial cells. 1461 3

Cyclic GMP, produced in response to nitric oxide and natriuretic peptides, is a key regulator of vascular smooth muscle cell contractility, growth, and differentiation, and is implicated in opposing the pathophysiology of hypertension, cardiac hypertrophy, atherosclerosis, and vascular injury/restenosis. cGMP regulates gene expression both positively and negatively at transcriptional as well as at posttranscriptional levels. cGMP-regulated transcription factors include the cAMP-response element binding protein CREB, the serum response factor SRF, and the nuclear factor of activated T cells NF/AT. cGMP can regulate CREB directly, through phosphorylation by cGMP-dependent protein kinase, or indirectly, through activation of mitogen-activated protein kinase pathways; regulation of SRF and NF/AT by cGMP is indirect, through modulation of RhoA and calcineurin signaling, respectively. Downregulation of the RNA-binding protein HuR by cGMP leads to destabilization of guanylate cyclase mRNA, but this posttranscriptional mechanism may affect many more cGMP-regulated genes. In this review, we discuss the role of cGMP-regulated gene expression in (patho)physiological processes most relevant to the cardiovascular system, such as regulation of vascular tone, cardiac hypertrophy, phenotypic modulation of vascular smooth muscle cells, and regulation of cell proliferation and apoptosis.
 ...
PMID:Regulation of gene expression by cyclic GMP. 1464 34

Scavenger receptor CD36 plays important roles in atherosclerosis, inflammation, thrombosis, and angiogenesis. Statins besides lowering serum cholesterol levels, exhibit a variety of effects on inflammation, coagulation and atherosclerosis lesion stability. PPAR-gamma ligands influence macrophage responses to many inflammatory stimuli. Herein, we investigated in human monocytes the effect of statins alone, and in combination with PPAR-gamma ligands on CD36 expression, as well as the molecular mechanisms underlying the regulatory action of statins. Our results demonstrate that statins upregulate both CD36 surface protein and mRNA by potentiating the transcription of the CD36 gene. Furthermore, the combination of statins and PPAR-gamma ligands has an additive effect on CD36 expression. Effects of statins on CD36 expression were prevented by mevalonate and geranylgeraniol, indicating the requirement of geranylgeranylated proteins for CD36 regulation. Rho GTPases inhibitor C3 exoenzyme reproduced the effect of statins, while Rho activator lysophosphatidic acid downregulated CD36. Transient expression of dominant-negative mutants of RhoA and RhoB induced a significant increased in CD36 promoter activity. Finally, the actin cytoskeleton disrupter cytochalasin D upregulated CD36. These data indicate that Rho proteins are important modulators of CD36 expression, and strongly suggest that statins increased CD36 expression by disrupting cytoskeleton organization by inactivating Rho GTPases. These features prompt to investigate the roles of Rho GTPases and actin cytoskeleton modulators on monocytic functions affected by statins.
 ...
PMID:Statins upregulate CD36 expression in human monocytes, an effect strengthened when combined with PPAR-gamma ligands Putative contribution of Rho GTPases in statin-induced CD36 expression. 1469 43

UTP stimulates the expression of pro-inflammatory vascular cell adhesion molecule-1 (VCAM-1) in endothelial cells through activation of the P2Y(2) nucleotide receptor P2Y(2)R. Here, we demonstrated that activation of the P2Y(2)R induced rapid tyrosine phosphorylation of vascular endothelial growth factor receptor (VEGFR)-2 in human coronary artery endothelial cells (HCAEC). RNA interference targeting VEGFR-2 or inhibition of VEGFR-2 tyrosine kinase activity abolishes P2Y(2)R-mediated VCAM-1 expression. Furthermore, VEGFR-2 and the P2Y(2)R co-localize upon UTP stimulation. Deletion or mutation of two Src homology-3-binding sites in the C-terminal tail of the P2Y(2)R or inhibition of Src kinase activity abolished the P2Y(2)R-mediated transactivation of VEGFR-2 and subsequently inhibited UTP-induced VCAM-1 expression. Moreover, activation of VEGFR-2 by UTP leads to the phosphorylation of Vav2, a guanine nucleotide exchange factor for Rho family GTPases. Using a binding assay to measure the activity of the small GTPases Rho, we found that stimulation of HCAEC by UTP increased the activity of RhoA and Rac1 (but not Cdc42). Significantly, a dominant negative form of RhoA inhibited P2Y(2)R-mediated VCAM-1 expression, whereas expression of dominant negative forms of Cdc42 and Rac1 had no effect. These data indicate a novel mechanism whereby a nucleotide receptor transactivates a receptor tyrosine kinase to generate an inflammatory response associated with atherosclerosis.
 ...
PMID:The P2Y2 nucleotide receptor mediates vascular cell adhesion molecule-1 expression through interaction with VEGF receptor-2 (KDR/Flk-1). 1517 47

Monocyte-endothelial interaction plays a pivotal role in atherosclerosis. We previously showed that HMG CoA reductase inhibitor reduces adhesion, however, not the rolling of monocytes to vascular endothelium under flow in vitro. In the present study, we investigated the effect of pitavastatin, a novel HMG CoA reductase inhibitor, on the transition from monocyte rolling on vascular endothelium to stable adhesion induced by MCP-1 under flow (shear stress = 1.0 dyne/cm(2)). Control THP-1 cells rolled on activated (IL-1beta, 4 hours) human umbilical vein endothelial cells (HUVEC) and the number of adhered THP-1 cells were significantly enhanced following the addition of 50 nM of MCP-1 (p < 0.002). In contrast, MCP-1 failed to convert pitavastatin-treated (10 microM, 48 hours) THP-1 rolling to stable adhesion, as compared to baseline adhesion, prior to the addition of MCP-1 (p > 0.4). Pitavastatin-induced changes in THP-1 cells were reversed by treatment with 10 microM of mevalonate, the intermediate of cholesterol biosynthesis. To elucidate the mechanism by which pitavastatin modulates MCP-1-induced THP-1 adhesive interactions, the possible involvement of extracellular signal-regulated kinase 1/2 (ERK1/2) was examined. Western blotting analysis using an anti-ERK1/2 Ab and an antibody against phosphorylated-ERK1/2 (p-ERK) revealed that pitavastatin treatment significantly inhibited the MCP-1-induced phosphorylation of ERK1/2. Further, a RhoA pull-down assay revealed that activation of RhoA GTPase was reduced after pitavastatin treatment. Interestingly, an inhibitor of RhoA GTPase, but not that of the ERK1/2 pathway, attenuated MCP-1-dependent adhesion of THP-1 cells to HUVEC. These findings indicate a role for pitavastatin in modulating the MCP-1-induced phenotypic changes of monocyte-endothelial interactions, which may account for the anti-inflammatory effects of statins.
 ...
PMID:MCP-1-induced enhancement of THP-1 adhesion to vascular endothelium was modulated by HMG-CoA reductase inhibitor through RhoA GTPase-, but not ERK1/2-dependent pathway. 1523 91

Endothelial dysfunction is characterized by multiple interactions between endothelial cells and components of the blood. This study focussed on the induction of the pro-atherogenic connective tissue growth factor (CTGF) in endothelial cells by bioactive lipids and platelets. Lysophosphatidic acid (LPA) and sphingosine-1-phosphate (S1P) led to a time- and concentration-dependent increase in CTGF mRNA and protein expression in the human endothelial cell line EAHY 926 and in primary cultures of human umbilical vein endothelial cells (HUVEC). As both cell types expressed various receptors for LPA and S1P, signaling pathways were further characterized by pharmacological means: induction of CTGF was pertussis toxin-insensitive and inhibition of activation of p42/44 MAP kinases only partially reduced CTGF expression. On the contrary, interference with the RhoA signaling pathway by simvastatin, an inhibitor of geranylgeranyltransferases, or the Rho-kinase inhibitor Y27632 prevented induction of CTGF. Co-incubation of endothelial cells with freshly isolated human platelets significantly increased the expression of CTGF mRNA in endothelial cells, which was also sensitive to simvastatin. Up-regulation of CTGF in endothelial cells, induced by LPA, S1P, or platelets, may contribute to the initiation and progression of atherosclerosis. Interference of simvastatin with the synthesis of this pro-atherogenic factor further supports the anti-atherogenic role of statins.
Atherosclerosis 2004 Aug
PMID:Induction of connective tissue growth factor (CTGF) in human endothelial cells by lysophosphatidic acid, sphingosine-1-phosphate, and platelets. 1526 82

Monocyte migration is one of the key events occurring in the early stage of atherosclerosis. This process includes monocytic adhesion to and penetration through the arterial intima. In such an environment, many factors stimulate the monocytes to enhance integrin activation and extracellular matrix degradation. To investigate the coordinative operation of these two events in relation to monocyte migration, we paid particular attention to the effects of granulocyte-macrophage colony-stimulating factor (GM-CSF) on monocytes in terms of RhoA activation and matrix metalloproteinase (MMP) expression. RhoA and integrin clustering were activated by GM-CSF, monocyte chemoattractant protein-1 (MCP-1) and platelet-derived growth factor-BB (PDGF-BB) in human monocytic cell lines. Furthermore, enhancement of migration was observed with stimulation by MCP-1 and PDGF-BB. Granulocyte-macrophage colony-stimulating factor did not enhance the migration, even though it activated RhoA and integrin. However, GM-CSF is known to stimulate monocytes to express MCP-1, suggesting the presence of an indirect mechanism for GM-CSF-mediated migratory activity. In contrast, only GM-CSF enhanced the expression of MMP-1 and MMP-9. These results provide evidence that GM-CSF has multiple functions enhancing monocytic migration via RhoA and integrin activation, and via MMP expression.
 ...
PMID:GM-CSF activates RhoA, integrin and MMP expression in human monocytic cells. 1536 38

Although lipid-lowering therapy with 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) decreases the progression of coronary artery and aortic valve calcification, the mechanism of action of these drugs to inhibit the calcification process remains unclear. In this study, we investigated the effect of statins such as cerivastatin and atorvastatin on vascular calcification by utilizing an in vitro model of inflammatory vascular calcification. Cerivastatin and atorvastatin dose-dependently inhibited in vitro calcification of human vascular smooth muscle cells (HVSMCs) induced by the following inflammatory mediators (IM): interferon-gamma, 1alpha,25-dihydroxyvitamin D3, tumor necrosis factor-alpha, and oncostatin M. These statins also depressed expression of alkaline phosphatase (ALP) in HVSMCs induced by these factors. Mevalonate and geranylgeranylpyrophosphate reversed the inhibitory effect of cerivastatin on ALP expression in HVSMCs, while farnesylpyrophosphate showed no effect on the ALP activities inhibited by this drug, suggesting that inhibition of Rho and its downstream target, Rho kinase may mediate the inhibitory effect of cerivastatin. Cerivastatin prevented RhoA activation in HVSMCs induced by the IM. A specific inhibitor of Rho kinase (Y-27632) inhibited in vitro calcification and induction of ALP in HVSMCs. These findings provide a possible mechanism of statins to prevent the progression of calcification in inflammatory vascular diseases such as atherosclerosis and cardiac valvular calcification.
 ...
PMID:Statins inhibit in vitro calcification of human vascular smooth muscle cells induced by inflammatory mediators. 1538 84


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>