This study showed that blueberry extract exerted antidepressant-like effects. - GreenMedInfo Summary

OBJECTIVE: Major depressive disorder is a debilitating and recurrent psychiatric disorder. Blueberries have several biological properties, including neuroprotective effects, through antioxidant and anti-inflammatory actions. The aim of this study was to evaluate the effect of blueberry extract on depressive-like behavior and lipopolysaccharide (LPS)-induced neurochemical changes.

METHODS: Mice were pretreated with vehicle, fluoxetine (20 mg/kg) or blueberry extract (100 or 200 mg/kg) intragastrically for seven days before intraperitoneal LPS (0.83 mg/kg) injection. Twenty-four hours after LPS administration, mice were submitted to behavioral tests. Oxidative stress and neuroinflammatory parameters were evaluated in the cerebral cortex, hippocampus, and striatum.

RESULTS: Our data showed that blueberry extract or fluoxetine treatment protected against LPS-induced depressive-like behavior in tail suspension and splash tests (< 0.05), without changes in locomotor activity (> 0.05). LPS induced an increase in the levels of reactive oxygen species (< 0.001), nitrite (< 0.05) and thiobarbituric acid reactive substances (< 0.01), as well as a reduction in total sulfhydryl content (< 0.05) and catalase activity (< 0.05) in brain structures; blueberry extract restored these alterations (< 0.05). In addition, blueberry extract attenuated the increase in tumor necrosis factor-alpha (TNF-α) levels induced by LPS administration (< 0.05).

CONCLUSION: This study showed that blueberry extract exerted antidepressant-like effects, protected the brain against oxidative damage, and modulated TNF-α levels induced by LPS.