Protective effect of green tea extract on ischemia/reperfusion-induced brain injury in Mongolian gerbils

Brain Res. 2001 Jan 5;888(1):11-18. doi: 10.1016/s0006-8993(00)02935-8.

Abstract

Free radical-induced oxidative damages of macromolecules and cell death are important factors in the pathogenesis of ischemia/reperfusion brain injury. In the present study, an investigation as to whether green tea extract reduces ischemia/reperfusion-induced brain injury in Mongolian gerbils was conducted. The effect of green tea on the ischemia/reperfusion-induced production of hydrogen peroxide, lipid peroxidation and oxidative DNA damage (formation of 8-hydroxydeoxyguanosine), and cell death in addition to locomotor activity was studied. Two doses (0.5 or 2%) of green tea extract were added into the drinking water and to be accessed by animals ad libitum for 3 weeks prior to the induction of ischemia. A global ischemia was induced by the bilateral occlusion of the common carotid arteries for 5 min. Reperfusion was achieved by releasing the occlusion and restoring blood circulation for 48 h. The infarction volumes were 112+/-31 mm(3) and 76+/-11 mm(3) in the 0.5 and 2% green tea pretreated animals compared to 189+/-12 mm(3) in the ischemia/reperfusion animals. Green tea extract also reduced the levels of ischemia/reperfusion-induced hydrogen peroxide (from 1470+/-170 to 1034+/-46 and 555+/-30 nmole/mg protein), lipid peroxidation products (from 1410+/-210 to 930+/-40 and 330+/-20 nmole/mg protein) and 8-oxodG (from 3.9+/-0.1 to 2.8+/-0.3 and1.9+/-0.3 ng/microg DNA, x10(-2)) by pretreatment of 0.5 or 2% green tea for 3 weeks, respectively. Moreover, green tea also reduced the number of ischemia/reperfusion-induced apoptotic cells (from 59+/-12 to 37+/-8, 15+/-11 apoptotic cells/high power field in the striatum region) and locomotor activity (from 15140+/-2940 to 3900+/-600 and 4100+/-1200). This study therefore suggests that green tea may be a useful agent for the prevention of cerebral ischemia damage.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 8-Hydroxy-2'-Deoxyguanosine
  • Aldehydes / metabolism
  • Animals
  • Apoptosis / drug effects
  • Beverages*
  • Brain / blood supply
  • Brain / cytology
  • Brain / metabolism*
  • Brain Infarction / drug therapy
  • Cerebrovascular Circulation / drug effects
  • Cysteine Proteinase Inhibitors / metabolism
  • DNA / metabolism
  • Deoxyguanosine / analogs & derivatives*
  • Deoxyguanosine / metabolism
  • Female
  • Gerbillinae
  • Hydrogen Peroxide / metabolism
  • Ischemic Attack, Transient / drug therapy*
  • Lipid Peroxidation / drug effects
  • Malondialdehyde / metabolism
  • Motor Activity / drug effects
  • Neurons / cytology
  • Neurons / metabolism
  • Oxidative Stress / drug effects
  • Plant Extracts / pharmacology*
  • Reperfusion Injury / drug therapy*

Substances

  • Aldehydes
  • Cysteine Proteinase Inhibitors
  • Plant Extracts
  • Malondialdehyde
  • 8-Hydroxy-2'-Deoxyguanosine
  • DNA
  • Hydrogen Peroxide
  • Deoxyguanosine
  • 4-hydroxy-2-nonenal