Korean J Physiol Pharmacol.  2007 Jun;11(3):85-88.

Effects of (-)-Epigallocatechin-3-gallate on Brain Infarction and the Activity Change of Matrix Metalloproteinase-9 Induced by Middle Cerebral Artery Occlusion in Mice

• Qian YR
• Kook JH
• Hwang S
• Kim DK
• Kim JK

Abstract

Matrix metalloproteinases (MMPs) can degrade a wide range of extracellular matrix components. It has been reported that MMP-9 are activated after focal ischemia in experimental animals. (-)-Epigallocatechin-3-gallate (EGCG), a major constituent of green tea polyphenols, is a potent free radical scavenger and reduces the neuronal damage caused by oxygen free radicals. And it has been known that EGCG could reduce the infarction volume in focal brain ischemia and inhibit MMP-9 activity. To delineate the relationship between the anti-ischemic action and the MMP-9-inhibiting action of EGCG, we investigated the effect of EGCG on brain infarction and the activity of matrix metalloproteinase-9 induced by permanent middle cerebral artery occlusion (pMCAO) in ICR mice. EGCG (40 mg/kg, i.p. 15~30 min prior to MCAO) significantly decreased infarction volume at 24 hr after MCAO. GM 6001 (50 mg/kg, i.p. 15~30 min prior to MCAO), a MMP inhibitor, also significantly reduced infarction volume. In zymogram, MMP-9 activities began to increase at ipsilateral cortex at 2 hr after MCAO, and the increments of MMP-9 activities were attenuated by EGCG treatment. Western blot for MMP-9 also showed patterns similar to that of zymogram. These findings demonstrate that the anti-ischemic action of EGCG in mouse focal cerebral ischemia involves its inhibitory effect on MMP-9.

Keyword

(-)-Epigallocatechin-3-gallate (EGCG); Permanent middle cerebral artery occlusion; Matrix metalloproteinase-9 (MMP-9); Mouse

MeSH Terms

Animals
Blotting, Western
Brain Infarction*
Brain Ischemia
Brain*
Extracellular Matrix
Free Radicals
Infarction
Infarction, Middle Cerebral Artery*
Ischemia
Matrix Metalloproteinase 9*
Matrix Metalloproteinases
Mice
Mice, Inbred ICR
Middle Cerebral Artery*
Neurons
Oxygen
Polyphenols
Tea
Free Radicals
Matrix Metalloproteinase 9
Matrix Metalloproteinases
Oxygen
Polyphenols
Tea