Docosahexaenoic acid promotes neurite growth in hippocampal neurons.
Docosahexanoic acid (22:6n-3; DHA) deficiency during development is associated with impairment in learning and memory, suggesting an important role of DHA in neuronal development. Here we provide evidence that DHA promotes neuronal differentiation in rat embryonic hippocampal primary cultures. DHA deficiency in vitro was spontaneously induced by culturing hippocampal cells in chemically defined medium. DHA supplementation improved DHA levels to values observed in freshly isolated hippocampus. We found that DHA supplementation in culture increased the population of neurons with longer neurite length per neuron and with higher number of branches. However, supplementation with arachidonic, oleic or docosapentaenoic acid did not have any effect, indicating specificity of the DHA action on neurite growth. Furthermore, hippocampal cultures obtained from n-3 fatty acid deficient animals contained a lower DHA level and a neuronal population with shorter neurite length per neuron in comparison to those obtained from animals with adequate n-3 fatty acids. DHA supplementation to the deficient group recovered the neurite length to the level similar to n-3 fatty acid adequate cultures. Our data demonstrates that DHA uniquely promotes neurite growth in hippocampal neurons. Inadequate neurite development due to DHA deficiency may contribute to the cognitive impairment associated with n-3 fatty acid deficiency.
Calderon
Frances
F
Section of Mass Spectrometry, Laboratory of Membrane Biochemistry and Biophysics, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, Maryland, USA.
Kim
Hee-Yong
HY
D000818:Animals; D016718:Arachidonic Acid / Q000494:pharmacology; D002478:Cells, Cultured; D004042:Dietary Fats, Unsaturated / Q000494:pharmacology; D019587:Dietary Supplements; D004281:Docosahexaenoic Acids / Q000494:pharmacology*; D015525:Fatty Acids, Omega-3 / Q000494:pharmacology; D005231:Fatty Acids, Unsaturated / Q000494:pharmacology; D005526:Food, Formulated; D020439:Growth Cones / Q000187:drug effects; D006624:Hippocampus / Q000166:cytology / Q000187:drug effects* / Q000196:embryology; D016501:Neurites / Q000187:drug effects*; D009474:Neurons / Q000166:cytology / Q000187:drug effects* / Q000648:ultrastructure; D051381:Rats; D017207:Rats, Sprague-Dawley
D004042:Dietary Fats, Unsaturated; D015525:Fatty Acids, Omega-3; D005231:Fatty Acids, Unsaturated; D004281:Docosahexaenoic Acids; D016718:Arachidonic Acid; C026219:docosapentaenoic acid