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)

It has been suggested that the intraluminal thrombus of abdominal aortic aneurysms (AAAs) predisposes for AAA enlargement and rupture. The growth of the AAA is dependent on proteolytic degradation of elastin. Here, we analysed whether the neutrophil gelatinase-associated lipocalin (NGAL) is expressed within the thrombus and the aneurysm wall. NGAL can bind to metalloproteinase-9 (MMP-9) and inhibit its degradation, thereby preserving enzymatic activity. Biopsies were obtained from thrombus-free and thrombus-covered aneurysm wall and the intraluminal thrombus from patients undergoing elective surgery for AAA. Immunohistochemistry and real-time PCR were used to study NGAL and MMP-9 expression. Immunoprecipitation, gel zymography, Western blot and ELISA were used to detect and quantify NGAL/MMP-9 complexes. NGAL was detected in the thrombus, the interface between the thrombus and the underlying wall and in the wall itself. Double staining showed that neutrophils are the major source of NGAL expression. Immunoprecipitation of MMP-9 with antibody against NGAL showed that complexes of NGAL and active MMP-9 were present in thrombus, the interface fluid and the aneurysm wall. Western blot analyses using non-reducing conditions and gel zymography demonstrated that high-molecular-weight complexes of NGAL/MMP-9 were present within the different regions. The concentration of the NGAL/MMP-9 complex was highest in the luminal part of the thrombus. In conclusion, NGAL in complex with activated MMP-9 is present in AAA wall and thrombus. Neutrophil-derived NGAL could enhance the proteolytic activity associated with AAA, but the importance of this mechanism for aneurysm growth remains to be shown.
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PMID:Presence of NGAL/MMP-9 complexes in human abdominal aortic aneurysms. 1772 27

Matrix metalloproteinase-9 (MMP-9) is involved in the remodeling process by degrading extracellular matrix, which is fundamental in maintaining structural integrity and favorable mechanical properties of the artery vascular wall. Neutrophil gelatinase-associated lipocalin (NGAL) seems to enhance MMP-9 activity. ELISA test was used to evaluate plasma MMP-9 and NGAL values. Moreover, Western blot analysis and RT-PCR were used to evaluate expression of MMP-9 and NGAL in aneurysmatic tissue with respect to healthy endothelial tissue of the same patient. In this rare case of abdominal aortic aneurysm associated with multiple peripheral aneurysms, both plasma and tissue levels of MMP-9 and NGAL seemed to correlate with disease progression. More studies and clinical trials are necessary to confirm our findings.
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PMID:Increased plasma levels of metalloproteinase-9 and neutrophil gelatinase-associated lipocalin in a rare case of multiple artery aneurysm. 2398 49