Background:
Elevated matrix metalloproteinase-9 (MMP-9) following acute ischemic stroke is associated with blood-brain barrier breakdown and hemorrhagic conversion. Prior retrospective evidence suggests that sulfonylurea use may be associated with reduced risk of hemorrhagic conversion. We hypothesized that sulfonylureas may reduce MMP-9 level in stroke patients.
Methods:
Using serial plasma samples from six subjects in the Glyburide Advantage in Malignant Edema and Stroke Pilot trial (GAMES-Pilot), we evaluated the level of MMP-9 in human subjects presenting with large hemispheric stroke who were treated with intravenous glyburide (RP-1127). MMP-9 was measured in a control cohort with large ischemic stroke who were not treated with glyburide. Commercially available ELISA kits and gel zymography were used to measure MMP-9 at baseline and at approximately 48 hours after stroke. GAMES subjects had additional time points analyzed until approximately 84 hours after stroke.
Results:
Average MMP-9 level in glyburide-treated stroke patients was 47.2 ± 8.0 ng/mL compared to 143.4 ± 60.35 ng/mL in untreated control subjects (p=0.004). Zymography analysis demonstrated a significant decrease in the pro-enzyme but no change in the active form of MMP-9. There was no difference in the level of the MMP-9 specific inhibitor, TIMP-1. No subjects exhibited parenchymal hemorrhagic conversion on 24 hour head CT scan.
Conclusions:
Glyburide treatment in human stroke patients with large hemispheric stroke is associated reduced level of MMP-9. Elucidating the underlying mechanism of glyburide’s effect on MMP-9 and the risk of hemorrhagic conversion may highlight future directions of therapy, including in combination with intravenous tissue plasminogen activator (IV t-PA).