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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    • "Within the polyphenol family, flavonoids have been shown to ameliorate learning and memory in both animals and humans. Flavanols, and particularly epicatechin and catechin, present in grape seeds, green tea or cocoa for example, have been shown to ameliorate learning and memory in animals (Devi et al., 2006; Haque et al., 2006; van Praag et al., 2007; Kaur et al., 2008; Asha Devi et al., 2011; Rendeiro et al., 2013b) and in humans (Dinges, 2006). Anthocyanins, present in red berries as in blueberries, have also been shown to prevent memory deficits in aged animals (Cho et al., 2003; Ramirez et al., 2005; Barros et al., 2006; Shukitt-Hale et al., 2006; Rendeiro et al., 2013b). "
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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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    • "Catechins and epigallocatechin-3-gallate (EGCG) are abundant in teas derived from the tea plant Camellia sinensis. These products show the effect of ameliorating a variety of human diseases such as cancers, atherosclerotic lesions, and Alzheimer's disease [66–70]. Recent studies [37, 38] have shown that they also attenuate the Helicobacter pylori-triggered caspase-1 signaling pathway, oxidative stress, and apoptosis in the gastric mucosa of the Helicobacter pylori-infected mouse model. "
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