Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0162871 (abdominal aortic aneurysm)
 8,664 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

While the renin-angiotensin system (RAS) is widely recognized to be involved in atherosclerosis, its potential role in the progression from atherosclerotic lesions to abdominal aortic aneurysm (AAA) is poorly understood. The present study aimed to investigate which components of the RAS may render the atherosclerotic aorta aneurysmatic. The expression of renin, prorenin/renin receptor, angiotensinogen, AT1- and AT2 receptors, cathepsin D, cathepsin G and chymase was examined by immunoblotting and immunohistochemistry in human atherosclerotic, aneurysmatic and healthy aortic tissues obtained from patients undergoing elective repair or at autopsy. AT1- and AT2 receptor mRNA expression was determined using quantitative real-time RT-PCR. All investigated local RAS components were up-regulated in atherosclerotic as compared to healthy tissues. AAA compared to atherosclerosis was characterized by a further increase in the expression of all RAS components except for the AT2 receptor. Cathepsin D was exclusively up-regulated in AAA. Most RAS components co-localized with infiltrating leukocytes or mast cells pointing to their contribution to inflammatory processes. Due to their proteolytic features, some RAS components (cathepsin D and cathepsin G and chymase) may contribute to AAA formation by accessory mechanisms. Taken together, our data suggest that in humans, RAS activation is not just a key-player in the pathogenesis of atherosclerosis, but that a further increasing activation may be involved in the transition from atherosclerosis to AAA.
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PMID:Transition from atherosclerosis to aortic aneurysm in humans coincides with an increased expression of RAS components. 1919 79

Evaluation of: Pagano MB, Bartoli MA, Ennis TL et al.: Critical role of dipeptidyl peptidase I in neutrophil recruitment during the development of experimental abdominal aortic aneurysms. Proc. Natl Acad. Sci. USA 104(8), 2855-2860 (2007). In this study, the authors used dipeptidyl peptidase I (DPPI) gene-targeted mice and an aortic elastase perfusion-induced mouse abdominal aortic aneurysm (AAA) model to examine the role of DPPI, also termed cathepsin C, in the development of AAA. Mice lacking this protease are resistant to AAA formation. Interestingly, these authors found that DPPI activity controls neutrophil recruitment to the sites of inflammation, specifically AAA lesions in this case. By producing chemokine CXCL2, neutrophils in AAA lesions recruit additional neutrophils to the lesion sites where these cells utilize DPPI to activate neutrophil serine proteases, including neutrophil elastase, cathepsin G and proteinase 3, which may be further used to stimulate macrophage cytokine and chemokine production. In addition to DPPI-deficient mice, the authors also used antibodies against neutrophils (Gr-1) or CXCL2 receptor, CXCR2, to deplete neutrophils or to block the action of neutrophil chemokines to affirm their hypothesis.
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PMID:Role of cathepsin C in elastase-induced mouse abdominal aortic aneurysms. 1980 79

Mast cells (MCs) regulate inflammation and immunity. Their granular content includes heparin, histamine, and several enzymes (tryptase, chymase, carboxypeptidase, and cathepsin G). In addition, activated MCs synthesize and release eicosanoids and a large number of cytokines and chemokines. Recent findings suggest a role of MCs in abdominal aortic aneurysms (AAAs) in humans, where they are found in the media and adventitia. Experimentally induced AAA in MC-deficient animals and animals treated with MC inhibitors demonstrate that MCs are involved in the pathogenesis of AAA via several different mechanisms. MC-dependent activation of metalloproteinases and the renin-angiotensin system, contribution to smooth muscle cell apoptosis, and release of proteolytic enzymes are some key examples. Human studies indicate that MCs are the main source of cathepsin G in AAAs and contribute to activation of the renin-angiotensin system via chymase and cathepsin G. Activated MCs also contribute to neovascularization, inflammation, and atherosclerosis, all hallmarks of AAA. Thus, we may envision that MC stabilizing agents, as well as leukotriene receptor antagonists and histamine receptor blockers already in clinical use for treatment of other diseases, could also be tested for their efficacy in preventing development and growth of AAA.
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PMID:Mast cells: important players in the orchestrated pathogenesis of abdominal aortic aneurysms. 2120 88

Remodeling of extracellular matrix (ECM) plays an important role in both atherosclerosis and aneurysm disease. Serine protease inhibitor A3 (serpinA3) is an inhibitor of several proteases such as elastase, cathepsin G and chymase derived from mast cells and neutrophils. In this study, we investigated the putative role of serpinA3 in atherosclerosis and aneurysm formation. SerpinA3 was expressed in endothelial cells and medial smooth muscle cells in human atherosclerotic lesions and a 14-fold increased expression of serpinA3n mRNA was found in lesions from Apoe-/- mice compared to lesion-free vessels. In contrast, decreased mRNA expression (-80%) of serpinA3 was found in biopsies of human abdominal aortic aneurysm (AAA) compared to non-dilated aortas. Overexpression of serpinA3n in transgenic mice did not influence the development of atherosclerosis or CaCl2-induced aneurysm formation. In situ zymography analysis showed that the transgenic mice had lower cathepsin G and elastase activity, and more elastin in the aortas compared to wild-type mice, which could indicate a more stable aortic phenotype. Differential vascular expression of serpinA3 is clearly associated with human atherosclerosis and AAA but serpinA3 had no major effect on experimentally induced atherosclerosis or AAA development in mouse. However, serpinA3 may be involved in a phenotypic stabilization of the aorta.
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PMID:Serine protease inhibitor A3 in atherosclerosis and aneurysm disease. 2258 Jul 63