Antidepressant-like effect of kiwifruit (Actinidia deliciosa) extract on mouse models of depression

Antidepressant pharmacotherapies have a slow onset of clinical efficacy which is critical for therapeutic outcome and patient compliance. In recent years, an increasing number of studies suggest that phytochemical compounds activity on mood might be a clinically relevant co-adjuvant to current medications. Many studies suggest a positive association between fruits and vegetables-rich diet and prevention of depression, therefore the consumption of a whole phytocomplex may increase serotonin bioavailability both at CNS and systemic levels. The aim of this study is to evaluate the activity of kiwifruit (Actinidia deliciosa) extracts on mood in murine model of depressive behavior. Indeed, kiwifruit is rich in polyphenols (e.g. ferulic acid, kaempferol, catechin, etc.) with a known inhibitory effect on both monoamine oxidases A and B. Naïve male C57BL/6J mice were administered with three increasing concentrations of kiwifruit extracts under chronic or acute regimes. Immobility time was then assessed in forced swimming test (FST) and tail suspension test (TST); additionally, the efficacy of kiwifruit compared to vehicles and selective serotonin reuptake inhibitor fluoxetine (20 mg/kg, i.p.) were investigated. The highest kiwifruit concentration produced a reduction of 40% and 45% in immobility time in FST and TST respectively, without causing hyperlocomotion in the open-field test. Taken together, these data suggest that kiwifruit may have a mood-improving effect through modulation of the serotonergic system. To support these findings, pharmacokinetic profiles and monoamines detection through chromatographic and mass-spectrometric analyses are in progress on both whole brain homogenate and serum samples.