Upregulation of aneurysm wall AIF-1, MMP-9 and COX-2 expression in patients with ruptured intracranial aneurysm

Abstract

Objective To investigate the expression and significance of allograft inflammatory factor-1 (AIF-1), matrix metalloproteinase-9 (MMP-9), and cycloxygenase-2 (COX-2) in ruptured intracranial aneurysm tissue. Methods The aneurysm and superficial temporal artery specimens were collected from 12 patients with intracranial ruptured cystic aneurysms. Immunohistochemical staining was used to detect the expression levels of AIF-1, MMP-9 and COX-2 in the aneurysms and superficial temporal arteries. Results Inflammatory cell infiltration such as lymphocytes, macrophages were observed in the aneurysmal walls. The AIF-1, MMP-9 and COX-2 expression levels were mainly observed in the intima layer and intima-media of the ruptured aneurysm wall tissue, and they were mainly distributed in the cytoplasms of macrophages and lymphocytes, and they did not express or expressed very few in superficial temporal arteries. Semi-quantitative analysis showed that expression levels of AIF-1 (0.006 7[0.004 2-0.014 6]vs. 0.000 0[0.000 0-0.001 0]; Z=4.236, P<0.001), MMP-9 (0.002 2[0.000 7-0.004 3 ]vs. 0.000 0[0.000 0-0.000 0]; Z=-4. 442, P<0.001), and COX-2 (0.002 8[0.002 2-0.004 3]vs. 0.000 0[0.000 0-0.000 0]; Z=-4.442, P<0.001) in the aneurysmal wall were significantly higher than those in the superficial temporal artery. The expression level of AIF-1 in male patients was significantly higher than that in female patients (0.016±0.013 vs. 0.009±0.006; t=1.440, P=0.043). Conclusions The expression levels of AIF-1, MMP-9 and COX-2 of the ruptured intracranial saccular aneurysm walls were upregulated significantly, suggesting inflammatory response, and they might be involved in the occurrence, development and rupture process of intracranial aneurysms. Key words: Intracranial Aneurysm; Aneurysm, Ruptured; Calcium-Binding Proteins; Matrix Metalloproteinase 9; Cyclooxygenase 2; Inflammation; Temporal Arteries; AIF1 protein, human