Long-term administration of green tea catechins improves spatial cognition learning ability in rats

Department of Environmental Physiology, Shimane University Faculty of Medicine, Izumo 693-8501, Japan.
Journal of Nutrition (Impact Factor: 3.88). 05/2006; 136(4):1043-7.
Source: PubMed


Green tea catechins confer potent biological properties including antioxidation and free-radical scavenging. We investigated the effect of long-term oral administration of green tea catechins (Polyphenon E, PE: EGCG 63%; EC 11%; EGC 6%; ECG 6%) mixed with water on the spatial cognition learning ability of young rats. The learning ability of rats administered PE (0%, 0.1%, 0.5%) for 26 wk was assessed in the partially baited 8-arm radial maze. Relative to controls, those administered PE had improved reference and working memory-related learning ability. They also had lower plasma concentrations of lipid peroxides and greater plasma ferric-reducing antioxidation power than controls. Furthermore, rats administered PE had lower hippocampus reactive oxygen species concentrations than controls. We suggest that this improvement in spatial cognitive learning ability is due to the antioxidative activity of green tea catechins.

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Available from: Michio Hashimoto, Mar 22, 2014
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    • "In fact, EGCG can easily cross the BBB and reach the brain parenchyma [124]. Besides, long term administration was shown to improve spatial cognition and learning ability in rats [125] and to reduce cerebral amyloidosis in AD transgenic mice [126]. Moreover, the consumption of EGCG inhibits OS-induced neuronal degeneration and cell death in pre-and post-traumatic brain injury [127]. "
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