Antidepressant-like activity of zinc: further behavioral and molecular evidence

Zinc exhibits antidepressant-like activity in preclinical tests (the forced swim test and tail suspension test) and in olfactory bulbectomy and chronic unpredictable stress; two models of depression. Zinc also enhances the treatment of depression in humans. In the present study we evaluated the antidepressant activity of zinc in another model of depression-chronic mild stress (CMS) and the effect of zinc treatment on BDNF protein and the mRNA level. In CMS zinc hydroaspartate (10 mg/kg) exhibited a rapid (after 1 week of treatment) antidepressant-like effect. Chronic treatment with zinc induced a 17-39% increase in the BDNF mRNA and protein level in the hippocampus. These data indicate a rapidly acting antidepressant-like activity of zinc in CMS and the involvement of zinc in the regulation of BDNF.