MMP-12 and TIMP Behavior in Symptomatic and Asymptomatic Critical Carotid Artery Stenosis

Objective: The aim of this study was to evaluate the levels of matrix metalloproteinase-12 (MMP-12) and tissue inhibitors of metalloproteinases (TIMP)-1, TIMP-2, TIMP3, and TIMP-4 in patients with symptomatic and asymptomatic critical carotid artery stenosis (CAS). Methods: We enrolled 10 patients affected by symptomatic CAS within 12 hours from onset of stroke (S group) and 30 patients with asymptomatic CAS (CAS group); 31 patients matched for age, sex, and traditional cardiovascular risk factors were used as controls (RF group). Serum levels of MMP-12, TIMP-1, TIMP-2, TIMP-3, and TIMP-4 were assessed by Luminex. Results: MMP-12 levels were significantly higher both in the S and CAS groups than in the RF group (P <.001). We found a significant decrease of all TIMPs in the CAS group compared with the RF group, whereas a significant increase was observed in the S group compared with the CAS group. A significant increase of TIMP-3 and TIMP-4 levels was observed in the S group compared with all other groups. Conclusion: MMP-12 is related to critical CAS both symptomatic and asymptomatic, being mainly released in the late stage of plaque development. Moreover, we suggest that a specific pattern of matrix degrading enzyme inhibitors arises during the early phases of stroke.