Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

---

Query: UNIPROT:P05412 (c-Jun)
11,453 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The ability of modified low-density lipoptoteins (LDLs) to induce both proliferation and death of endothelial cells is considered to be a mechanism of early atherosclerosis development. We previously showed that carbamylated LDL (cLDL) induces human coronary artery endothelial cell (HCAEC) death in vitro. This effect is similar to the atherogenic action of oxidized LDL (oxLDL) that induces the proliferation and death of endothelial cells. The present study was designed to analyze a potential proliferative effect of cLDL and whether proliferation caused by modified LDLs is related to cell death. Cultured HCAECs were exposed to different concentrations of modified LDL or native LDL for varying periods of time. Cell proliferation measured by bromodeoxyuridine incorporation and S-phase analysis was dose-dependently increased in the presence of cLDL (6.25-200 microg/ml). The proliferation induced by cLDL or oxLDL was associated with cell death and increased phosphorylation of extracellular signal-regulated kinase (ERK) and c-Jun NH(2)-terminal kinase (JNK). Inhibition of cLDL- or oxLDL-induced proliferation by aphidicolin (1 microg/ml) was protective against both short-term cell death measured by lactate dehydrogenase release into the medium and long-term cell viability visualized by cell multiplication. Inhibition of ERK phosphorylation led to a significant decrease of DNA synthesis and cell rescue from injury by modified LDLs, while inhibition of JNK phosphorylation had an only partial rescue effect without involvement in cell proliferation. These data are the first evidence that endothelial cell death induced by cLDL or oxLDL is mediated by cell proliferation through the mitogen-activated protein kinase pathway.
...
PMID:Modified LDLs induce proliferation-mediated death of human vascular endothelial cells through MAPK pathway. 1715 46

Acrolein, which is a highly reactive alpha,beta-unsaturated aldehyde generated by lipid peroxidation, can affect cells and tissues and cause various disorders. Increased levels of unsaturated aldehydes play an important role in the pathogenesis of a number of human diseases such as Alzheimer's disease, atherosclerosis and diabetes. Acrolein is a highly ubiquitous toxic environmental pollutant. Because of human exposure, there is a need for investigating the mechanisms involved in acrolein toxicity at the cellular and molecular levels. Acrolein can induce cell death by apoptosis, although the mechanisms are not entirely clear. The present study investigates whether mitogen-activated protein kinases (MAPKs) play a role in activation of apoptosis by acrolein. Our findings show that acrolein-mediated apoptosis is in fact MAPK-dependent in Chinese hamster ovary cells. The MAP family kinases, including ERK and p38 kinase, and the transcription factor c-Jun were all activated by phosphorylation after 1 h exposure to acrolein. Phosphorylation of ERK and p38 kinases and their blockade by an ERK inhibitor, U0126, or a p38 inhibitor, SB203580, respectively, suggested that activation of apoptosis by acrolein is ERK- and p38-dependent. Thus, blockade of ERK and p38 inhibited chromatin condensation, caspase-7 and -9 activation as well as ICAD cleavage induced by acrolein. JNK and AKT kinases seem to be implicated in survival pathways against acrolein insult, since their respective inhibitors, SP600125 and LY294002/Wortmannin switched the mode of cell death from apoptosis to total necrosis. Finally, acrolein induced phosphorylation of the pro-apoptotic factor p53 which is responsible for transcription of pro-apoptotic factors such as Bax and Fas ligand. These results provide new information demonstrating the implication of MAPKs and AKT in acrolein-induced apoptosis, and this information may be useful for understanding the pathogenesis of a number of tissue diseases and environmental toxicity in response to acrolein.
...
PMID:P38 and ERK mitogen-activated protein kinases mediate acrolein-induced apoptosis in Chinese hamster ovary cells. 1719 91

Osteopontin (OPN) is a proinflammatory cytokine implicated in the chemoattraction of monocytes and the development of atherosclerosis. Peroxisome proliferator-activated receptor (PPAR)alpha, a ligand-activated transcription factor with pleiotropic anti-inflammatory effects in macrophages, is the molecular target for fibrates, which are frequently used to treat dyslipidemia in patients with type 2 diabetes at high risk for cardiovascular disease. In the present study, we examined the regulation of OPN by PPARalpha agonists in macrophages and determined the effect of fibrate treatment on OPN plasma levels in patients with type 2 diabetes. Treatment of human macrophages with the PPARalpha ligands bezafibrate or WY14643 inhibited OPN expression. PPARalpha ligands suppressed OPN promoter activity, and an activator protein (AP)-1 consensus site conferred this repression. Overexpression of c-Fos and c-Jun reversed the inhibitory effect of PPARalpha ligands on OPN transcription, and, in chromatin immunoprecipitation assays, PPARalpha ligands inhibited c-Fos and phospho-c-Jun binding to the OPN promoter. Moreover, c-Fos and phospho-c-Jun protein expression was inhibited by PPARalpha agonists, indicating that PPARalpha ligands suppress OPN expression through negative cross talk with AP-1-dependent transactivation of the OPN promoter. This inhibitory effect of PPARalpha ligands on OPN expression was absent in PPARalpha-deficient macrophages, suggesting a receptor-mediated mechanism of OPN suppression. Finally, treatment of type 2 diabetic patients with bezafibrate significantly decreased OPN plasma levels. These results demonstrate a novel mechanism whereby PPARalpha ligands may impact macrophage inflammatory responses and decrease early proinflammatory markers for cardiovascular disease.
...
PMID:PPARalpha agonists suppress osteopontin expression in macrophages and decrease plasma levels in patients with type 2 diabetes. 1736 Sep 82

Atherosclerosis is a key factor in vascular disease, and cigarette smoking is a well-known risk factor that may induce an inflammatory response and enhance plaque formation in arteries. Thromboxane (Tx) is one key inflammatory mediator involved in the pathogenesis of cardiovascular disease. The present study was designed to test if lipid soluble smoking particles (DSP) enhance TxA(2) receptor (TP) expression in rat mesenteric arteries, and if intracellular mitogen-activated protein kinase (MAPK) pathways play a role. Organ culture of rat mesenteric arteries in the presence of DSP (0.2 microl/ml for 24h) resulted in markedly elevated contractile responses to the Tx analog U46619, compared with the control DMSO. There was no increase in TP receptor mRNA expression, while the protein expression was significantly enhanced. This up-regulation was not affected by a general transcriptional inhibitor actinomycin D, but was almost completely abolished by cycloheximide, a general translational inhibitor. Dexamethasone, a glucocorticoid, manifested a potent inhibitory effect as well. These results suggest that the up-regulation of TP receptor occurs via post-transcriptional events, and mainly translation. This is supported by experiments with specific inhibitors for c-Jun-NH(2)-terminal kinase (SP600125), extracellular signal-regulated kinase 1 and 2 (PD98059 and U0126) and p38 (SB203580) that had no inhibitory effect on the up-regulation of TP receptors. Collectively, the results show that MAPK pathways are not involved in TP receptor up-regulation. Study on TP receptor mRNA stability showed that during organ culture, the TP receptor mRNA was stable in both DMSO and DSP group, but the latter elicited a tendency to stabilize the TP receptor mRNA at higher level. Thus, post-transcriptional mechanisms are responsible for the up-regulation of TP receptor by DSP, in which enhanced translation is the major cause of the elevated protein expression and the enhanced contraction.
Atherosclerosis 2008 Feb
PMID:Up-regulation of thromboxane A2 receptor expression by lipid soluble smoking particles through post-transcriptional mechanisms. 1770 24

Insulin levels are a marker for cardiovascular events, but the link between hyperinsulinemia and atherosclerosis is poorly understood. We previously showed that insulin increases monocyte-endothelial interactions and the endothelial expression of the pro-atherogenic vascular cell adhesion molecule-1 (VCAM-1). The aim of this study is to examine molecular mechanisms involved in the effect of insulin on VCAM-1 expression. Human umbilical vein endothelial cells (HUVEC) were incubated with insulin (0-24 h)+/- inhibitors of signaling pathways potentially involved. At pathophysiological concentrations (10(-9)-10(-7) M), insulin selectively induced VCAM-1 expression. The p38 mitogen activated protein(MAP) kinase inhibitors SB203580 and SB202190, and partially the c-Jun NH2-terminal kinase (JNK) inhibitor SP600127, decreased insulin effect on VCAM-1. Gene silencing by small interfering RNA significantly reduced the expression of p38MAP kinase, and this was accompanied by suppression of insulin-stimulated VCAM-1 expression. Treatment with insulin also led to the activation of NF-KB and induction of IKB-alpha phosphorylation, thus accounting for NF-KB translocation into the nucleus. Co-treatment of HUVEC with insulin and SB202190 strongly reverted the stimulatory effect of insulin on NF-KB activation, thus establishing a link between NF-KB activation and p38MAPkinase-mediated induction of VCAM-1 by insulin. In conclusion, pathophysiological insulin concentrations increase VCAM-1 expression and activate NF-KB. This mostly occurs through stimulation of p38MAP kinase.
...
PMID:The prominent role of p38 mitogen-activated protein kinase in insulin-mediated enhancement of VCAM-1 expression in endothelial cells. 1788 Jul 67

Although estrogen replacement therapy may improve dampened endothelial function in postmenopausal women, the associated risk of breast and ovarian cancer has limited its long-term use. Identifying effective alternative remedy with less carcinogenicity is in serious demand. This study was designed to examine the effect of the phytoestrogen alpha-zearalanol (alpha-ZAL) on homocysteine-induced endothelin-1 (ET-1) induction, reactive oxygen species (ROS) production and transcription pathways in human umbilical vein endothelial cells (HUVECs). ROS was measured by DCF fluorescent microscopy. Homocysteine-induced expression of ET-1 mRNA, ERK, pERK and c-jun/AP-1 protein was measured using RT-PCR and Western blot analysis, respectively. ET-1 secretion was determined by the enzymatic immunoassay. Transcriptional factor AP-1 expression in response to alpha-ZAL, homocysteine or both was evaluated by transient transfection assay. Our data revealed that alpha-ZAL ablated homocysteine-elicited ET-1 secretion, upregulated ET-1 mRNA and homocysteine-induced ROS accumulation without any effects by itself. alpha-ZAL also nullified homocysteine-induced increase in c-Jun/AP-1 expression/activity without eliciting any effect by itself. Collectively, our data indicated that alpha-ZAL may antagonize homocysteine-induced ET-1 gene induction, ROS accumulation, activation of ERK signaling pathway and AP-1 transcriptional factor, all of which may contribute to alpha-ZAL-induced beneficial effect on endothelial function.
Atherosclerosis 2008 Apr
PMID:Phytoestrogen alpha-zearalanol inhibits homocysteine-induced endothelin-1 expression and oxidative stress in human umbilical vein endothelial cells. 1790 May 92

Chlamydophila pneumoniae is known to be associated with atherosclerosis. Recent studies have reported that components of Chlamydophila pneumoniae (chlamydophilal antigens) induce foam cell formation in macrophages. However, the mechanism of foam cell formation induced by chlamydophilal antigens has yet to be elucidated. In this paper, we first found that mitogen-activated protein kinases including extracellular signal-regulated kinase, p38 and c-Jun NH2 terminal kinase are phosphorylated after stimulation by chlamydophilal antigens. We then showed that chlamydophilal antigens induce foam cell formation mainly via c-Jun NH2 terminal kinase. Finally, we demonstrated that foam cell formation and phosphorylation of mitogen-activated protein kinases induced by chlamydophilal antigens are mainly recognized through Toll-like receptor 2. These results collectively indicated that chlamydophilal antigens induce foam cell formation mainly via Toll-like receptor 2 and c-Jun NH2 terminal kinase.
...
PMID:Chlamydophilal antigens induce foam cell formation via c-Jun NH2-terminal kinase. 1791 39

Hyperhomocysteinemia is characterized by abnormally high concentrations of homocysteine (Hcy) in the plasma. It is a metabolic disorder associated with dysfunction of several organs such as atherosclerosis, altered lipid metabolism, and liver injury. In this study we investigated the effect of Hcy on transcriptional regulation of monocyte chemoattractant protein-1 (MCP-1), a potent chemokine, expression in hepatocytes. Hyperhomocysteinemia was induced in rats by a high-methionine diet for 4 weeks. MCP-1 mRNA and protein levels were significantly elevated in the liver tissue homogenate and in hepatocytes of hyperhomocysteinemic rats. The role of transcription factors in MCP-1 expression was examined by electrophoretic mobility shift assay. Activation of activator protein (AP)-1 but not nuclear factor kappaB was detected in the liver tissue of those rats. Incubation of rat hepatocytes with Hcy (50-200 microm) caused a significant increase in AP-1 activation followed by an increase in intracellular MCP-1 mRNA expression and an elevation of MCP-1 protein secreted into the culture medium. Hcy markedly increased the DNA binding activity of human recombinant AP-1 (c-Fos and c-Jun proteins). The presence of a sulfhydryl group in Hcy was essential for Hcy-induced AP-1 activation. When hepatocytes were transfected with decoy AP-1 oligodeoxynucleotide to inhibit AP-1 activation, Hcy-induced MCP-1 mRNA expression was abolished. Further analysis revealed that increased hepatic MCP-1 expression was positively correlated with the serum MCP-1 level. These results suggest that Hcy-induced MCP-1 expression in the liver is mediated via AP-1 activation, which may contribute to chronic inflammation associated with hyperhomocysteinemia.
...
PMID:Homocysteine induces monocyte chemoattractant protein-1 expression in hepatocytes mediated via activator protein-1 activation. 1802 59

Hibiscus sabdariffa L. (Malvaceae), an attractive plant believed to be native to Africa, is cultivated in Sudan and in eastern Taiwan. It has been reported to contain a number of protocatechuic acid and anthocyanins. In vitro experimental studies have shown that anthocyanins administration of the extract produces anti-inflammation and chemoprevention effects. In spite of the wide use of Hibiscus sabdariffa L. in folk medicine for treating various diseases, our previous study indicated a potency of Hibiscus sabdariffa extract (HSE) in anti-atherosclerosis. The mechanisms of anthocyanins administration of the extract produce from Hibiscus sabdariffa L. to attenuate atherosclerosis were not clarified. In this study, we found that Hibiscus anthocyanins (HAs) could inhibit the serum-stimulated proliferation of smooth muscle cell (SMC) and result in cell apoptosis. The HAs inducing cell apoptosis was dose dependent. We further used SB203580 (p38 inhibitor) to block cellular apoptosis and evaluate its effect on the HAs-inducing SMC death via some apoptosis criteria including DNA fragmentation and flow cytometry. We suggested that the mechanisms of the inhibitory effect of HAs on atherosclerosis could be via inhibiting the proliferation of SMC. HAs induces apoptosis via (i) activating p38 MAP kinase that subsequently phosphorylates target protein c-Jun and transduces the signal to further activate the apoptotic protein cascades that contain Fas-mediated signaling (Fas/caspase-8 signaling module) and (ii) activating p53 and inducing bax expression. As an outcome of the events, cytochrome c releases from the mitochondria, leading to cell apoptosis. In these experiments, HAs showed strong potential to induce SMC cell apoptosis via p38 and p53 pathway. In consequence, the rate of atherosclerotic formation is slowed down, and the progress is suppressed.
...
PMID:Effect of Hibiscus anthocyanins-rich extract induces apoptosis of proliferating smooth muscle cell via activation of P38 MAPK and p53 pathway. 1803 Jun 61

Endothelial cells (ECs) play an important role in hypoxia-induced vascular disorders. We investigated the acute hypoxia effect on endothelial expression of activating transcription factor 3 (ATF3), a stress-inducible transcription factor playing significant roles in cellular responses to stress. Bovine aortic ECs were subjected to acute hypoxia (1% O(2), pO(2)=8 mmHg) and ATF3 expression was examined. ECs exposed to hypoxia transiently induced ATF3 expression. A transient increase in the activation of c-Jun-NH(2)-terminal kinase (JNK) and p38 mitogen-activated protein kinase (MAPK) in ECs was observed; however, only ECs pretreated with a specific inhibitor to JNK suppressed the hypoxia-induced ATF3 expression. ECs exposed to acute hypoxia transiently increased endothelial nitric oxide (eNOS) activity. Pre-treating ECs with a specific inhibitor to eNOS (l-NAME) or PI3-kinase significantly inhibited the hypoxia-induced JNK activation and ATF3 expression. ATF3 induction has been shown to inhibit matrix metalloproteinase-2 (MMP-2) expression. Consistently, ECs exposed to hypoxia attenuated the MMP-2 expression. This hypoxia-attenuated MMP-2 expression can be rescued by pre-treating ECs with an inhibitor of eNOS. These results suggest that the ATF3 induction by acute hypoxia is mediated by nitric oxide and the JNK pathway in ECs. Our findings provide a molecular basis for the mechanism in which ECs respond to acute hypoxia.
Atherosclerosis 2008 Dec
PMID:Acute hypoxia to endothelial cells induces activating transcription factor 3 (ATF3) expression that is mediated via nitric oxide. 1837 12


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

---