Evaluation of the Therapeutic Potential of Oral Phycocyanin-Rich Spirulina Extract in Neuropsychiatric Disorders

Aim: Spirulina is a microalga that is widely used as a food supplement and is regarded as having performance enhancing and health promoting properties. We conducted a preliminary evaluation of the possible antidepressant, anti-anxiety, pro-socialization and cognition-enhancing effects of Spirulina in mouse models. Methods: Sixty male BalbC mice aged 3 weeks were administered phycocyanin-rich Spirulina extract (PRSE, 545 mg/kg), fluoxetine (20 mg/kg) or water orally for 5 weeks. During the last 2 weeks of the experiment a series of behavioral-cognitive tests was performed to evaluate motor activity, antidepressant and anti-anxiety effects, socialization and cognitive effects. Effects of PRSE and fluoxetine were compared to those of water. Results: There was a significant effect of PRSE in the activity domain, manifesting as an increase in velocity in the open field (p=0.0007 vs. water). Fluoxetine significantly enhanced immobility in the tail suspension test and the forced swim test reflecting the known antidepressant effect of this compound, but not PRSE. There were no significant effects of PRSE in tests of anxiety, socialization or cognition. Conclusions: The most striking observation in this study was that PRSE significantly enhanced activity in the open field test. Further studies are indicated to confirm and extend this finding and investigate possible mechanisms of action. The results of the current study do not support sporadic reports of possible antidepressant or cognition-enhancing effects of PRSE. Nevertheless, additional studies are indicated using depression models rather than naive mice, alternative mouse strains, using additional cognitive tests, and administering higher PRSE doses.