The role of 5-HT1A receptors in fish oil-mediated increased BDNF expression in the rat hippocampus and cortex: A possible antidepressant mechanism

• Published in: Neuropharmacology Vol. 62; no. 1; pp. 184 - 191
• Main Authors: Vines, Aparecida, Delattre, Ana Marcia, Lima, Marcelo M.S., Rodrigues, Laís Soares, Suchecki, Deborah, Machado, Ricardo B., Tufik, Sergio, Pereira, Sofia I.R., Zanata, Sílvio M., Ferraz, Anete Curte
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01-01-2012
• Subjects: 5-HT1A receptors; Analysis of Variance; Animals; BDNF; Brain-Derived Neurotrophic Factor - metabolism; Cerebral Cortex - drug effects; Cerebral Cortex - metabolism; Depression; Depression - diet therapy; Depression - pathology; Depression - physiopathology; Disease Models, Animal; Exploratory Behavior - drug effects; Fatty Acids, Omega-3 - administration & dosage; Female; Fenclonine - pharmacology; Fish oil; Hippocampus - drug effects; Hippocampus - metabolism; Immobility Response, Tonic - drug effects; Male; Motor Activity - drug effects; Neurochemistry; Piperazines - pharmacology; Polyunsaturated fatty acids; Rats; Rats, Wistar; Receptor, Serotonin, 5-HT1A - metabolism; Serotonin; Serotonin Antagonists - pharmacology; Swimming - psychology; Depression; Serotonin; Polyunsaturated fatty acids; BDNF; Fish oil; 5-HT1A receptors
• ISSN: 0028-3908; 1873-7064
• DOI: 10.1016/j.neuropharm.2011.06.017

Epidemiological and dietary studies show that nutritional deficit of omega-3 polyunsaturated fatty acids (ω-3 PUFA) is directly related to the prevalence and severity of depression. Supplementation with docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) during critical periods of development (pregnancy and lactation) is essential for cortical maturation, synaptogenesis and myelination, and may also mitigate the risk for cognitive deficits and psychopathologies in young adults. The present study was performed to evaluate the involvement of serotonin (5-HT) receptors, particularly of 5-HT1A, and hippocampal brain-derived neurotrophic factor (BDNF) expression in the antidepressant effect of ω-3 PUFA supplementation. In Experiment 1, the antidepressant effects of fish oil were assessed by the modified forced swim test in adult rats. The data indicated a robust antidepressant effect produced by this supplementation and that treatment of the rats with WAY 100135 reversed this effect. In Experiment 2, cortical and hippocampal contents of BDNF, 5-HT, dopamine (DA) and its metabolites, 5-hydroxyindoleacetic acid (5-HIAA), and 3,4-dihydroxyphenylacetic acid (DOPAC), were determined in animals subjected to the same protocol. Increased BDNF expression in the cortex and hippocampus of both age groups was detected. In 90 day-old rats, 5-HT content in the hippocampus was increased, whereas 5-HIAA formation was diminished in the fish oil group. We suggest the occurrence of a reciprocal involvement of 5-HT1A receptors activation and the hippocampal BDNF-increased expression mediated by fish oil supplementation. These data corroborate and expand the notion that supplementation with ω-3 PUFA produces antidepressant effects mediated by an increase in serotonergic neurotransmission, particularly in the hippocampus.
This article is part of a Special Issue entitled ‘Anxiety and Depression’.
► The antidepressant-like behavior induced by fish oil involves the serotoninergic system. ► 5-HT1A receptor and BDNF expression are involved in fish oil antidepressant effect. ► Early ω-3 supplementation presumably prevents psychopathologies in young adulthood.