Abstract 4522: Elevation of Matrixmetalloproteinases in Different Areas of Thoracic Aortic Aneurysm in Bicuspid And Tricuspid Aortic Valve
Background: Aneurysm is a common disease among patients with bicuspid aortic valve (BAV). Many studies have observed abnormalities of matrix metalloproteinases in aneurysmal tissue. However, in the literature, there are many statements about different matrix protein expression in aneurysmal tissues. This study investigated matrix proteins in tissue from sino-tubular junction, proximal- and distal convexity, and concavity aorta using a simultaneous multiplex protein detection system.
Methods: Tissue samples were collected from 41 patients with thoracic aortic aneurysms (aortic diameter 53,7±5,6 mm/31m, 10f) 31 patients with BAV (mean age 50,9±13,1 years), 10 patients with tricuspid aortic valve (TAV, mean age 63,2±8,2 years). The damage of the extracellular matrix (ECM) in 4 different areas was monitored using simultaneous detection techniques, including the measurement of matrix metalloproteinases (MMPs) and their inhibitors (TIMPs). Inflammatory processes were observed using immunohistochemistry.
Results: A significant amount of MMP-2, MMP-8, MMP-9, TIMP-2, TIMP-3 and TIMP-4 was detected in multiplex system in tissues of the right antero-lateral aspect (outer curves, convexity) in comparison with tissues obtained from the opposite site (inner curves, concavity). MMP-2 was elevated in the concave higher compared to the convex aortic site (118,5±61,2 vs 96,0±47,6 pg/ml, p=0,04). MMP-8 was elevated higher in the convex versus concave aortic site (7,1 vs 2,8 pg/ml, p=0,001; BAV 6,5 vs 2,1 pg/ml, p=0,001; TAV 8,9 vs 4,9 pg/ml), MMP-9 was elevated in the convex site (18,3 vs 8,9 pg/ml, p=0,008; BAV 16,8 vs 7,1 pg/ml, p=0,007; TAV 22,7 vs 14,6) in tissues obtained from aortic aneurysm. We found TIMP-3 to be elevated in tissues obtained from BAV and TAV in the concave compared with convex aortic site (10,4 vs 8,8 pg/ml, p=0,0007, BAV 9,6 vs 10,8 pg/ml, p=0,01; TAV, 6,4 vs 9,2 pg/ml, p=0,01). TIMP-2 and TIMP-4 were elevated significantly near the aortic root compared BAV vs TAV.
Conclusions: Simultaneous protein detection of MMPs/TIMPs was revealed locally different elevation of MMP-2, MMP-8, MMP-9, TIMP-2, TIMP-3, and TIMP-4 in different aortic sites of the same patient.