The potential contributions of matrix metalloproteinase 8,9 and 13 (MMP-8,9,13) to cerebral vasospasm and the role of doxycycline inhibitors on gene expression after experimental subarachnoid haemorrhage

Introduction:
Vasospasm has been reported as the most important cause of mortality and morbidity in patients with subarachnoid haemorrhage (SAH) who can reach the hospital. Matrix metalloproteinases (MMPs) are a gene family, which are called neutral proteases in the central nervous system (CNS). In this experimental study we studied the upregulation of MMPs (MMP-8, MMP-9, and MMP-13) gene expression and the inhibitor effects of doxycycline after experimental SAH model in rats.

Material and methods:
After 24 Wistar Albino rats were divided into groups, a SAH model was created by transfusion of autologous blood from the cisterna magna, and then 30 mg/kg doxycycline treatment was applied. In order to observe the efficacy of the treatment, MMP-8, MMP-9 and MMP-13 gene expression levels were examined, and histopathological examinations were made in the sections taken.

Results:
There was a statistically significant increase (p < 0.05) in MMP-8, MMP-9 and MMP-13 gene expression within the first 6 hours after SAH. The Ct parameter specifies the number of cycles in which the detected fluorescence radiation threshold value is exceeded. The MMP-13 Ct difference in the SAH group was significantly higher (p = 0.037) than the control group.

Conclusions:
The pathophysiology of cerebral vasospasm is complex and multifactorial. Many studies are conducted to solve the complex mechanism of cerebral vasospasm. It has been shown that the use of doxycycline causes a statistically significant (p < 0.05) inhibition at gene expression levels (MMP-8, MMP-9 and MMP-13), even in a single dose of usage and also these results have been confirmed by histopathology examination.