A non-steroidal anti-inflammatory agent provides significant protection during focal ischemic stroke with decreased expression of matrix metalloproteinases.

The present study was designed to investigate whether the neuroprotective effect of nimesulide was mediated by inhibiting expression of matrix metalloproteinase-9 (MMP-9) and/or matrix metalloproteinase-2 (MMP-2) in a rat model of thrombolytic reperfusion after the embolic focal cerebral ischemia (FCI). It was found that nimesulide at therapeutically relevant doses (3, 6 and 12 mg/kg) decreased neurological deficits, infarct volume, brain index and brain water content in a dose-dependent manner. Hemorrhagic transformation was reduced by 64% with treatment of 12 mg/kg nimesulide. Quantitative analysis of immunohistochemical staining of brain slices showed that the neuron number expressing MMP-9 and MMP-2 increased in the model animals treated with vehicle (p<0.01 vs sham group), and significantly decreased in nimesulide-treated animals (p<0.05 or p<0.01 vs vehicle group). Our results demonstrate that nimesulide significantly reduces the degree of neuronal injury and hemorrhage transformation caused by thrombolytic reperfusion after the embolic FCI, and that inhibition of MMP-9 and MMP-2 expression contributes at least in part to the neuroprotection.