Memory deficits and oxidative stress in cerebral ischemia-reperfusion: neuroprotective role of physical exercise and green tea supplementation

Neurobiol Learn Mem. 2014 Oct:114:242-50. doi: 10.1016/j.nlm.2014.07.005. Epub 2014 Jul 22.

Abstract

Ischemic stroke is a major cause of morbidity and mortality all over the world. Among impairments observed in survivors there is a significant cognitive learning and memory deficit. Neuroprotective strategies are being investigated to minimize such deficits after an ischemia event. Here we investigated the neuroprotective potential of physical exercise and green tea in an animal model of ischemia-reperfusion. Eighty male rats were divided in 8 groups and submitted to either transient brain ischemia-reperfusion or a sham surgery after 8 weeks of physical exercise and/or green tea supplementation. Ischemia-reperfusion was performed by bilateral occlusion of the common carotid arteries during 30 min. Later, their memory was evaluated in an aversive and in a non-aversive task, and hippocampus and prefrontal cortex were removed for biochemical analyses of possible oxidative stress effects. Ischemia-reperfusion impaired learning and memory. Reactive oxygen species were increased in the hippocampus and prefrontal cortex. Eight weeks of physical exercise and/or green tea supplementation before the ischemia-reperfusion event showed a neuroprotective effect; both treatments in separate or together reduced the cognitive deficits and were able to maintain the functional levels of antioxidant enzymes and glutathione.

Keywords: Antioxidants; Brain; Green tea; Ischemia–reperfusion; Memory; Oxidative stress; Physical exercise.

MeSH terms

  • Animals
  • Antioxidants / pharmacology*
  • Antioxidants / therapeutic use
  • Avoidance Learning / drug effects
  • Avoidance Learning / physiology
  • Male
  • Memory Disorders / drug therapy
  • Memory Disorders / etiology
  • Memory Disorders / metabolism
  • Memory Disorders / prevention & control*
  • Neuroprotective Agents / pharmacology*
  • Oxidative Stress / drug effects*
  • Oxidative Stress / physiology
  • Physical Conditioning, Animal / physiology*
  • Rats
  • Recognition, Psychology / drug effects
  • Recognition, Psychology / physiology
  • Reperfusion Injury / complications
  • Reperfusion Injury / drug therapy
  • Reperfusion Injury / metabolism
  • Reperfusion Injury / prevention & control*
  • Tea*

Substances

  • Antioxidants
  • Neuroprotective Agents
  • Tea