Picroside Ⅱ down-regulates matrix metalloproteinase-9 expression following cerebral ischemia/reperfusion injury in rats

Studies have shown that Picroside II attenuates inflammatory reactions following brain ischemia through the inhibition of the TLR-4-NF-κB signal transduction pathway,and ameliorates cerebral edema through the reduction of aquaporin-4 expression.Matrix metalloproteinase-9 (MMP-9),located downstream of the TLR-4-NF-κB signal transduction pathway,can degrade the neurovascular matrix,damage the blood-brain barrier to induce cerebral edema,and directly result in neuronal apoptosis and brain injury.Therefore,the present study further observed MMP-9 expression in the brain tissues of rats with cerebral ischemia/reperfusion injury following Picroside II treatment.Results demonstrated that Picroside II significantly reduced MMP-9 expression in ischemic brain tissues,as well as neuronal apoptosis and brain infarct volume,suggesting Picroside II exhibits neuroprotection by down-regulating MMP-9 expression and inhibiting cell apoptosis.