Evaluation of the Therapeutic Potential of Oral Phycocyanin-Rich Spirulina Extracts 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 anti-depressant, anti-anxiety, pro-socialization and cognition-enhancing effects of Spirulina in mouse models. Methods: Sixty male BalbC mice aged 3 weeks were administered with 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 were performed to evaluate motor activity, anti-depressant 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 anti-depressant effect of this compound, but not PRSE. There were no significant effects of PRSE found in the tests of anxiety, socialization or cognition. Conclusion: 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 the possible mechanisms of action. The results of the current study do not support sporadic reports of possible anti-depressant or cognition-enhancing effects of PRSE. Nevertheless, additional studies are indicated using depression models rather than naïve mice, alternative mouse strains, using additional cognitive tests, and administering higher PRSE doses.