Omega-3 Docosahexaenoic Acid Is a Mediator of Fate-Decision of Adult Neural Stem Cells

The mammalian brain is enriched with lipids that serve as energy catalyzers or secondary messengers of essential signaling pathways. Docosahexaenoic acid (DHA) is an omega-3 fatty acid synthesized de novo at low levels in humans, an endogenous supply from its precursors, and is mainly incorporated from nutrition, an exogeneous supply. Decreased levels of DHA have been reported in the brains of patients with neurodegenerative diseases. Preventing this decrease or supplementing the brain with DHA has been considered as a therapy for the DHA brain deficiency that could be linked with neuronal death or neurodegeneration. The mammalian brain has, however, a mechanism of compensation for loss of neurons in the brain: neurogenesis, the birth of neurons from neural stem cells. In adulthood, neurogenesis is still present, although at a slower rate and with low efficiency, where most of the newly born neurons die. Neural stem/progenitor cells (NSPCs) have been shown to require lipids for proper metabolism for proliferation maintenance and neurogenesis induction. Recent studies have focused on the effects of these essential lipids on the neurobiology of NSPCs. This review aimed to introduce the possible use of DHA to impact NSPC fate-decision as a therapy for neurodegenerative diseases.