title: Dietary omega-3 deficiency reduces BDNF content and activation NMDA receptor and Fyn in dorsal hippocampus: implications on persistence of long-term memory in rats.
abstract: Omega-3 (n-3) fatty acids are important for adequate brain function and cognition. The aim of the present study was to evaluate how n-3 fatty acids influence the persistence of long-term memory (LTM) in an aversive memory task and to explore the putative mechanism involved. Female rats received isocaloric diets that included n-3 (n-3 group) or not (D group). The adult litters were subjected to an inhibitory avoidance task (0.7 mA, 1.0 seconds foot shock) to elicit persistent LTM. Twelve hours after the training session, the fatty acid profile and the brain derived neurotrophic factor (BDNF) content of the dorsal hippocampus were assessed. In addition, we measured the activation of the NR2B subunit of the N-methyl-d-aspartate (NMDA) receptor and the SRC family protein Fyn. Despite pronounced learning in both groups, the persistence of LTM was abolished in the D group 7 days after the training session. We also observed that the D group presented reductions in hippocampal DHA (22:6 n-3) and BDNF content. Twelve hours after the training session, the D group showed decreased NR2B and Fyn phosphorylation in the dorsal hippocampus, with no change in the total content of these proteins. Further, there was a decrease in the interaction of Fyn with NR2B in the D group, as observed by co-immunoprecipitation. Taken together, these data suggest that n-3 fatty acids influence the persistence of LTM by maintaining adequate levels of DHA and BDNF as well as by influencing the activation of NR2B and Fyn during the period of memory formation.
authors.forename: Simone Azevedo
authors.initials: SA
authors.lastname: Bach
authors.forename: Letícia V
authors.initials: LV
authors.lastname: de Siqueira
authors.forename: Alexandre P
authors.initials: AP
authors.lastname: Müller
authors.forename: Jean P
authors.initials: JP
authors.lastname: Oses
authors.forename: Andreia
authors.initials: A
authors.lastname: Quatrim
authors.forename: Tatiana
authors.initials: T
authors.lastname: Emanuelli
authors.forename: Lúcia
authors.initials: L
authors.lastname: Vinadé
authors.forename: Diogo O
authors.initials: DO
authors.lastname: Souza
authors.forename: Júlia D
authors.initials: JD
authors.lastname: Moreira
mesh_terms: D000818:Animals; D019208:Brain-Derived Neurotrophic Factor / Q000187:drug effects*; D004281:Docosahexaenoic Acids / Q000378:metabolism; D015525:Fatty Acids, Omega-3 / Q000008:administration & dosage / Q000097:blood*; D005231:Fatty Acids, Unsaturated / Q000172:deficiency; D005260:Female; D006624:Hippocampus / Q000187:drug effects / Q000378:metabolism; D007858:Learning / Q000187:drug effects; D008568:Memory / Q000187:drug effects; D057567:Memory, Long-Term / Q000187:drug effects*; D010766:Phosphorylation; D051076:Proto-Oncogene Proteins c-fyn / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D016194:Receptors, N-Methyl-D-Aspartate / Q000378:metabolism*
chemical_list: D019208:Brain-Derived Neurotrophic Factor; D015525:Fatty Acids, Omega-3; D005231:Fatty Acids, Unsaturated; C121001:NR2B NMDA receptor; D016194:Receptors, N-Methyl-D-Aspartate; D004281:Docosahexaenoic Acids; C494961:Fyn protein, rat; D051076:Proto-Oncogene Proteins c-fyn
keywords: BDNF; Fyn; LTM; Memory; NMDA receptor; n-3 Fatty acids