Magnesium-deficient diet alters depression- and anxiety-related behavior in mice -: influence of desipramine and Hypericum perforatum extract

A relation between magnesium (Mg) status and mood disorders has been suggested. but evidence remains inconsistant. Therefore, we examined in mice whether Mg-depletion would alter behavior evaluated in established annual models of depression and anxiety and whether these effects would be sensitive to antidepressants. Compared to control mice fed with nomal diet, mice receiving a low Mg diet (10% of daily requirment) for several weeks displayed increased immobility time in the forced swim test. indicating enhanced depression-like behavior. In addition, the partial Mg-depletion increased anxiety-related behavior in the light/dark and open field test, while locomotor activity or motor coordination was not influenced. Chronic oral administration of desipramine (30 mg/kg/day), or Hypericum extract LI160 (Hyp, 380 mg/kg/day) prevented "pro-depression-like" forced swim behavior in Mg-depleted mice. Furthermore, the increase in anxiety-related behavior of Mg-depleted mice was abolished in both the open field and light dark test by Hyp. Taken together, we report that Mg-depletion leads to enhanced depression- and anxiety-related behavior in mice. which was further validated by the reversibility of the behavioral changes by known anti-depressant and anxiolytic substances. Further, the utility of Mg-depletion as a new screening model for clinically active anti-depressant and anxiolytic drugs is suggested. (C) 2004 Elsevier Ltd. All rights reserved.