OBJECTIVE: It has been suggested that the intraluminal thrombus of abdominal aortic aneurysms (AAAs) predisposes for AAA rupture. Here, we examined the possibility that the intraluminal thrombus influences expression and activity of matrix-degrading proteases in the AAA wall. METHODS AND RESULTS: Twenty patients undergoing elective repair of AAAs were included. From each patient, specimens from both thrombus-covered and thrombus-free wall were taken for analysis. Gene arrays and quantitative real-time polymerase chain reaction showed that matrix metalloproteinase (MMP)-1, -7, -9, and -12 expressions were upregulated in the thrombus-free wall compared with the thrombus-covered wall. Immunohistochemistry confirmed the differential expression of MMP-9 but also localized MMP-9 to the interface between the thrombus and the underlying vessel wall. MMP-9 expression was colocalized with the presence of macrophages. Similar expression patterns were observed for urokinase plasminogen activator (uPA), uPA receptor, and plasminogen activator inhibitor-1. Gelatinase activity was detected in the same regions as MMP-9 protein expression, ie, within the thrombus-free wall and in the interface between the thrombus and the underlying wall. CONCLUSIONS: The present work demonstrates that protease expression and activity differs within the aneurysm wall. The source and activity of the proteases responsible for the degradation of the thrombus-covered wall need to be further determined.
OBJECTIVE: It has been suggested that the intraluminal thrombus of abdominal aortic aneurysms (AAAs) predisposes for AAA rupture. Here, we examined the possibility that the intraluminal thrombus influences expression and activity of matrix-degrading proteases in the AAA wall. METHODS AND RESULTS: Twenty patients undergoing elective repair of AAAs were included. From each patient, specimens from both thrombus-covered and thrombus-free wall were taken for analysis. Gene arrays and quantitative real-time polymerase chain reaction showed that matrix metalloproteinase (MMP)-1, -7, -9, and -12 expressions were upregulated in the thrombus-free wall compared with the thrombus-covered wall. Immunohistochemistry confirmed the differential expression of MMP-9 but also localized MMP-9 to the interface between the thrombus and the underlying vessel wall. MMP-9 expression was colocalized with the presence of macrophages. Similar expression patterns were observed for urokinase plasminogen activator (uPA), uPA receptor, and plasminogen activator inhibitor-1. Gelatinase activity was detected in the same regions as MMP-9 protein expression, ie, within the thrombus-free wall and in the interface between the thrombus and the underlying wall. CONCLUSIONS: The present work demonstrates that protease expression and activity differs within the aneurysm wall. The source and activity of the proteases responsible for the degradation of the thrombus-covered wall need to be further determined.
Authors: A Rouchaud; C Johnson; E Thielen; D Schroeder; Y-H Ding; D Dai; W Brinjikji; J Cebral; D F Kallmes; R Kadirvel Journal: AJNR Am J Neuroradiol Date: 2015-12-31 Impact factor: 3.825
Authors: Amir Malkawi; Grisha Pirianov; Evelyn Torsney; Ian Chetter; Natzi Sakalihasan; Ian M Loftus; Ian Nordon; Christopher Huggins; Nicoletta Charolidi; Matt Thompson; Xie Yun Xu; Gillian W Cockerill Journal: Aorta (Stamford) Date: 2015-10-01
Authors: Fan Zhang; Greg Banker; Xiaodong Liu; Pasithorn A Suwanabol; Justin Lengfeld; Dai Yamanouchi; K Craig Kent; Bo Liu Journal: J Surg Res Date: 2010-05-11 Impact factor: 2.192