Title: | A flavonol present in cocoa [(-)epicatechin] enhances snail memory |
Author(s): | Fruson L; Dalesman S; Lukowiak K; |
Address: | "Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada, T2N 4N1" |
ISSN/ISBN: | 1477-9145 (Electronic) 0022-0949 (Linking) |
Abstract: | "Dietary consumption of flavonoids (plant phytochemicals) may improve memory and neuro-cognitive performance, though the mechanism is poorly understood. Previous work has assessed cognitive effects in vertebrates; here we assess the suitability of Lymnaea stagnalis as an invertebrate model to elucidate the effects of flavonoids on cognition. (-)Epicatechin (epi) is a flavonoid present in cocoa, green tea and red wine. We studied its effects on basic snail behaviours (aerial respiration and locomotion), long-term memory (LTM) formation and memory extinction of operantly conditioned aerial respiratory behaviour. We found no significant effect of epi exposure (15 mg l(-1)) on either locomotion or aerial respiration. However, when snails were operantly conditioned in epi for a single 0.5 h training session, which typically results in memory lasting ~3 h, they formed LTM lasting at least 24 h. Snails exposed to epi also showed significantly increased resistance to extinction, consistent with the hypothesis that epi induces a more persistent LTM. Thus training in epi facilitates LTM formation and results in a more persistent and stronger memory. Previous work has indicated that memory-enhancing stressors (predator kairomones and KCl) act via sensory input from the osphradium and are dependent on a serotonergic (5-HT) signalling pathway. Here we found that the effects of epi on LTM were independent of osphradial input and 5-HT, demonstrating that an alternative mechanism of memory enhancement exists in L. stagnalis. Our data are consistent with the notion that dietary sources of epi can improve cognitive abilities, and that L. stagnalis is a suitable model with which to elucidate neuronal mechanisms" |
Keywords: | "Animals Behavior, Animal/drug effects Cacao/chemistry Catechin/*pharmacology Conditioning, Operant Extinction, Psychological/drug effects Locomotion/drug effects Lymnaea/*drug effects/metabolism/physiology Memory, Long-Term/*drug effects Models, Animal Se;" |
Notes: | "MedlineFruson, Lee Dalesman, Sarah Lukowiak, Ken eng Canadian Institutes of Health Research/Canada Research Support, Non-U.S. Gov't England 2012/09/28 J Exp Biol. 2012 Oct 15; 215(Pt 20):3566-76. doi: 10.1242/jeb.070300" |