Detection of Serum Matrix Metalloproteinase-9
Matrix metalloproteinase-9 (MMP-9) is an important diagnostic biomarker
in aortic pathophysiology in which MMP-9 can weaken the aortic media by
degrading multiple extracellular components and DM patients have a
2-fold decreased level of MMP-9, which could restrict the degradation of
the aortic wall [12] . Plasma MMP-9 was measured by using an
enzyme-linked immunosorbent assay (ELISA), designed by R&D Systems
(Minneapolis, MN, USA), according to the manufacturer’s instructions and
protocols. Venous blood was drawn from all patients at admission (within
24 hours of symptom onset) and plasma samples were obtained after
centrifugation at 3500 rpm at 4 °C for 15 min immediately after
collection and then stored at −80 °C for further analysis. The MMP-9
level was measured on admission, at day 14 (after the acute phase) and
day 90 (after the subacute phase), at 6 and 12 months and then annually
during follow-up.