Figure 7.

Inhibition of MMP-9 ameliorates the exacerbation of ischemic brain damage by systemic inflammation. Systemic inflammation was induced by intraperitoneal IL-1β injection, and the effects of MMP-9 inhibition using the specific inhibitor, SB-3CT, on the extent of ischemic brain damage, brain edema, and the severity of neurological deficit were determined 24 h after MCAo. A–C, Systemic inflammation significantly exacerbated the volume of ischemic damage (A), the extent of brain edema (B), and the neurological deficit (C). Inhibition of MMP-9 significantly attenuated the deleterious effects of systemic inflammation on brain damage (A), edema (B), and neurological deficit (C). D, Representative cresyl violet-stained brain sections illustrate the exacerbation of brain damage by systemic inflammation and the attenuation of this effect by SB-3CT. E, SB-3CT prevented the hemorrhagic transformation (arrowheads) caused by systemic inflammation. F, G, Inhibition of MMP-9 also attenuated the potentiation of neutrophil infiltration (F) and gelatinolytic activity (G) caused by peripheral inflammatory challenge. A, B, F: *p < 0.05 versus vehicle (veh), ^#p < 0.05 versus IL-1β, one-way ANOVA followed by Student's t test with Bonferroni correction; C: *p < 0.05 versus vehicle, ^#p = 0.05 versus IL-1β, generalized Fisher's exact test with Bonferroni correction. Scale bars, 100 μm.