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)

In the last decade, the understanding of the molecular mechanisms of regulation of the inflammatory process in chronic inflammatory diseases has moved remarkably forward. Recent evidence in various fields has consistently indicated that T-cells play a key role in initiating and perpetuating inflammation, not only via the production of soluble mediators but also via cell/cell contact interactions with a variety of cell types through membrane receptors and their ligands. Signalling through CD40 and CD40 ligand is a versatile pathway that is potently involved in all these processes. In this article, we review how T-cells become activated by dendritic cells or inflammatory cytokines, and how these T-cells activate, in turn, monocytes/macrophages, endothelial cells, smooth muscle cells and fibroblasts to produce pro-inflammatory cytokines (tumour necrosis factor alpha, interleukin-6), chemokines (interleukin-8, monocyte chemotactic protein-1), tissue factor, the main initiator of the coagulation cascade in vivo, and finally matrix metalloproteinases, responsible for tissue destruction. Moreover, we discuss how CD40 ligand at inflammatory sites stimulates fibroblasts and tissue monocyte/macrophage production of VEGF, leading to angiogenesis, which promotes and maintains the chronic inflammatory process. This cascade of events is discussed in the context of disease initiation/progression, with particular reference to atherosclerosis and rheumatoid arthritis, and to potential novel therapeutic targets for their treatment.
 ...
PMID:T-cell-mediated signalling in immune, inflammatory and angiogenic processes: the cascade of events leading to inflammatory diseases. 1503 40

The vascular endothelial cell (EC) plays an essential role in the pathogenesis of inflammation, transplant rejection and tumour metastasis. Most research on vascular ECs uses human umbilical vein endothelial cells (HUVECs). However, HUVECs are derived from immune-naive foetal tissue, and show significant functional differences from adult vascular endothelium. In this paper, we characterise an alternative model based on human saphenous vein ECs (HSVECs), describe their culture conditions and provide a detailed functional comparison with HUVECs. Compared with HUVECs, HSVECs show an increased sensitivity to ox-LDL and a reduced response to cytokines, as indicated by adhesion molecule expression as well as leukocyte adhesion and transmigration. With respect to their ability to present antigen, HSVECs have a higher level of HLA-DR, CD40 and ICOS-L following cytokine stimulation. In addition, HSVECs upregulate the costimulatory ligand CD80 (B7.1) following CD40 ligation, and support allogeneic T cell proliferation, while HUVECs fail to express CD80. Due to differential expression of adhesion molecules, poorly differentiated tumour cell lines also showed more adhesion to HSVECs than to HUVECs. These results indicate that HSVECs have advantages over HUVECs for studying adult vascular endothelial pathology in vitro.
Atherosclerosis 2004 Apr
PMID:Phenotypic and functional differences between human saphenous vein (HSVEC) and umbilical vein (HUVEC) endothelial cells. 1506 90

CD40, a member of the nerve growth factor/tumor necrosis factor receptor superfamily, and its ligand, CD154, play essential roles in cell immune responses. The results of many studies have indicated that CD40-CD154 interaction can upregulate costimulatory molecules, activate antigen-presenting cells (APCs), influence T-cell priming and T-cell-mediated effector functions as well as participate in the pathogenic processing of chronic inflammatory diseases, such as autoimmune diabetes, graft rejection, atherosclerosis, and cancer. Ligation of CD40 on cancer cells was also found to produce a direct growth-inhibitory effect through cell cycle blockage and/or apoptosis with no overt side effects on normal cells and treatment with CD154 can heighten tumor rejection immune response as well. However, systemic treatment with CD154 has some potential risks. Therefore, searching for efficient and safe strategies of CD154-based cancer therapy has been a hot topic in human cancer research. This review focuses on the latest discovered functions of CD40-CD154 interaction in cell immune responses and on the new findings of CD154-based human cancer therapy.
 ...
PMID:The role of CD40-CD154 interaction in cell immunoregulation. 1515 77

Atherosclerosis is the major cause of cardiovascular disease. Hypercholesterolaemia, hypertension and cigarette smoking are the common risk factors for atherosclerosis. These risk factors unite behind a convergence of mechanism, involving oxidation and inflammation in the artery wall that, with time, gives rise to characteristic fatty-fibrous lesions. Physical trauma and inflammation produce lesion rupture, which can lead to clinical events such as heart attack and stroke, or resolve with plaque growth. Disease progression is marked by the inflammatory indicator CRP (C-reactive protein). Early indicators of heart attack are the inflammatory marker CD40, and the cardiac myofilament protein troponin. Coronary atherosclerosis is the common cause of heart failure (HF). Disordered calcium signalling to the myofilaments occurs in HF and in cardiomyopathy. Enhanced calcium signalling suppresses HF. Neuro-humoral and biomechanical processes, as seen in hypertension, produce cardiac hypertrophy, which predisposes to HF through apoptosis. Although in humans cardiac damage produces permanent loss of cells, because the heart cannot regenerate, developments in stem cell technology suggest that help is at hand.
 ...
PMID:Pathophysiology and biochemistry of cardiovascular disease. 1517 70

Atherosclerosis is a chronic inflammatory disease of the arterial wall, and T-cell-mediated immune responses to plaque antigens are a prominent component of the inflammatory process. In addition to antigen stimulation, T-cell responses require co-stimulatory signals, the best defined of which are delivered by B7 family molecules on antigen-presenting cells binding to CD28 on T cells. T-cell co-stimulation directly influences the CD40/CD154 immunoregulatory pathway, which is well known to influence atherosclerosis. This review discusses recent progress in understanding the role of B7 family molecules in atherosclerosis, and T-cell co-stimulation as an important link between innate immunity and adaptive immune responses to plaque antigens.
 ...
PMID:Co-stimulation and plaque-antigen-specific T-cell responses in atherosclerosis. 1517 68

Ligation of endothelial cell (EC) CD40 induces the expression of several proinflammatory cytokines as well as angiogenesis factors, including vascular endothelial growth factor (VEGF). Moreover, despite the reported importance of CD40 in cell-mediated immunity, little is known of the CD40-induced signaling pathways in EC. In this study, we have investigated the function of the Ras signaling pathway(s) for CD40-induced overexpression of VEGF. EC were transiently transfected with a full-length VEGF promoter-luciferase construct and a dominant-inhibitory mutant of Ras (Ras17N). Following transfection, ligation of CD40 with soluble CD40 ligand resulted in a significant increase in VEGF transcriptional activation, and the inhibitory mutant of Ras blocked this CD40-induced VEGF overexpression. Using EMSA and Western blot analysis, we demonstrated that CD40-dependent binding of nuclear protein(s) to the VEGF promoter and CD40-induced VEGF protein expression in EC were also inhibited by the Ras mutant. Immunoprecipitation studies revealed that ligation of CD40 on EC promoted an increased association of Ras with its effector molecules Raf, Rho, and phosphatidylinositol 3-kinase (PI3K). But, cotransfection of effector-loop mutants of Ras determined that only PI3K was functional for Ras-induced VEGF transcription. Also, wortmanin and a dominant-inhibitory mutant of PI3K inhibited CD40-induced overexpression of VEGF. Together these findings demonstrate that both Ras and PI3K are intermediaries in CD40-induced regulation of VEGF in EC. We believe our findings are of importance in several chronic inflammatory diseases, including atherosclerosis and allograft rejection associated with both CD40-CD40 ligand signaling as well as VEGF expression and function.
 ...
PMID:The CD40-induced signaling pathway in endothelial cells resulting in the overexpression of vascular endothelial growth factor involves Ras and phosphatidylinositol 3-kinase. 1518 29

Toll-like receptors (TLRs) and other pattern-recognition receptors (PRRs) of the innate immune system form functional receptor complexes that recognize and respond to pathogen-associated molecular patterns (PAMPs). Porphyromonas gingivalis is an important pathogen in human periodontitis and has also been implicated in atherosclerosis. A major virulence factor of this pathogen is the fimbriae, which function as a surface adhesin. Here we present evidence that fimbriae also constitute a predominant P. gingivalis proinflammatory molecule which activates the TLR signaling pathway resulting in induction of proinflammatory cytokines (IL-1beta, IL-6, and TNF-alpha) and chemokines (IL-8) in monocytic cells. Although TLR2 and TLR4 mediate cellular activation in response to fimbriae, other PRRs, namely CD14 and CD11b/CD18, are involved in the recognition of fimbriae. We thus propose that fimbriae function as a PAMP which interacts with a PRR multi-receptor complex, where CD14 and CD11b/CD18 function as recruiting receptors and TLRs function as signaling receptors. In addition to cytokine induction, TLR activation by fimbriae also results in upregulation of the CD40, CD80, and CD86 costimulatory molecules in antigen-presenting cells, suggesting that fimbriae are sensed as a potential "danger" to the host immune system. Moreover, proinflammatory cytokine induction is attenuated upon repeated cellular stimulation with P. gingivalis fimbriae. This mechanism of tolerance induction which serves to mitigate excessive and potentially harmful inflammatory reactions appears to be due partly to fimbria-induced downregulation of the expression of interleukin-1 receptor-associated kinase-1 (IRAK-1), an important signaling intermediate of the TLR pathway. Understanding the molecular basis of how the host recognizes and responds to P. gingivalis fimbriae is essential for developing molecular approaches to control P. gingivalis-induced inflammatory responses in periodontal disease and perhaps atherosclerosis.
 ...
PMID:Intracellular signaling and cytokine induction upon interactions of Porphyromonas gingivalis fimbriae with pattern-recognition receptors. 1519 95

The CD40-CD40L system has pleiotropic effects in a variety of cells and biological processes including immune response, thrombosis and atherogenesis. Within the immune system, these molecules represent a critical link between its humoral and cellular arms. As a result of these attributes and based on preclinical data in animals, anti-CD40L antibodies were tested in a variety of immunologic diseases including idiopathic thrombocytopenic purpura, psoriasis, Crohn's disease, systemic lupus erythematosus and transplantation. Phase I/II studies in humans with lupus nephritis demonstrated reduction of anti-double-stranded DNA (anti-dsDNA) antibodies but not of protective antibodies. Reduction of anti-DNA was associated with increased serum complement levels and reduced glomerular inflammation. As a result of thrombotic effects, observed even in patients negative for anti-cardiolipin antibodies, there is a temporary halt on further human studies. The reasons for the prothrombotic effects are not clear at present but may represent effects on platelets and/or the endothelium. In view of the significant immunomodulatory effects of anti-CD40L treatment in patients with lupus nephritis, the increasing realization of the importance of premature atherosclerosis in lupus and an increasing amount of data supporting a role for the CD40-CD40L interactions in this process, inhibition of this pathway deserves further exploration in lupus.
 ...
PMID:Lessons learned from anti-CD40L treatment in systemic lupus erythematosus patients. 1523 Feb 98

There is strong evidence for the role of oxidative stress in all stages of atherosclerosis. Oxidized low density lipoprotein (ox-LDL), a marker of oxidative stress, is present in the plasma as well as in the atherosclerotic arteries of patients with atherosclerosis. Ox-LDL leads to endothelial activation, dysfunction and injury. Recently, a novel lectin-like receptor for ox-LDL (LOX-1) has been identified, primarily in the endothelial cells, that allows uptake of ox-LDL into endothelial cells. This receptor is transcriptionally upregulated by tumour necrosis factor-a, angiotensin II, shear stress and ox-LDL. The expression of this receptor activates a variety of intracellular processes that leads to expression of adhesion molecules and endothelial activation. Recent studies show that LOX-1 activation leads to the expression of CD40/40 L in endothelial cells and upregulation of matrix metalloproteinases. This receptor is highly expressed in blood vessels of animals and humans with hypertension, diabetes mellitus and atherosclerosis. Co-localization of LOX-1 along with ox-LDL in the rupture-prone plaque suggests that this receptor may be involved in the precipitation of acute myocardial ischemia. Identification and regulation of this receptor and understanding of signal transduction pathways may lead to new therapies in disease states characterized by endothelial dysfunction.
 ...
PMID:The role of LOX-1, a novel lectin-like receptor for oxidized low density lipoprotein, in atherosclerosis. 1530 3

The CD40-CD154 dyad has a central role in the development of immune-inflammatory processes. Therefore, disruption of CD40 signaling has the potential to be therapeutically useful in a number of disease indications, including autoimmune syndromes, atherosclerosis, and allograft rejection. Blocking antibodies to CD154 have been successfully employed in experimental animal models, and recently in clinical trials, to prevent or treat these immunologically induced diseases. However, the thrombotic events observed in some of these studies raise important issues regarding future use of anti-CD154 antibodies in humans. In this study, we demonstrate that a small interfering RNA (siRNA) can effectively reduce the surface expression of the human CD40 costimulatory receptor. Moreover, by rendering endothelial cells unresponsive to CD154(+) Jurkat cell-mediated activation through RNA interference, induction of endothelial cell-adhesion molecule expression and leukocyte adhesion is prevented in vitro. Thus, anti-CD40 siRNA may become a safe and effective therapeutic option for interfering with CD40-CD154-mediated acute or chronic immune-inflammatory conditions.
 ...
PMID:RNAi-mediated silencing of CD40 prevents leukocyte adhesion on CD154-activated endothelial cells. 1531 68


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