Evaluation of the neuroprotective effects of lycopene in chronic mild stress induced depression in rats

Abstract

Depression is a heterogeneous brain disorder that can lead to many neurological and neurobehavioral changes Lycopene is a naturally occurring carotenoid that exhibits neuroprotection by improving antioxidant enzyme activities in rats Based on the role of oxidative stress in modulating depressive disorders the relationship between the neuroprotective and antioxidant potential of lycopene is evaluated Chronic mild stress procedure was used to induce depression in rats CMS induced rats were treated with lycopene at doses of 5 mg per kg 10 mg per kg, and 20 mg per kg After completing six weeks of chronic mild stress induction and treatment animals were studied for the effect of lycopene on chronic mild stress-induced behavioral biochemical, gene and protein expression changes in rats CMS and CMS plus vehicle treated rats significantly increased immobility time and decreased locomotor and exploratory behavior Lycopene treated groups significantly attenuated immobility time and exploratory behavior Rats exposed to CMS showed a substantial decrease in body weight and sucrose preference ratio reversed by lycopene treatment Rats exposed to CMS showed a significant increase in serum corticosterone and malondialdehyde formation and depletion of superoxide dismutase catalase and glutathione peroxidase in the hippocampus Lycopene treatment significantly reversed these changes Anti apoptotic protein Bcl 2 was significantly down regulated in CMS and CMS plus Vehicle groups These changes were also found to be reversed by lycopene treatment Brain monoamines were substantially reduced in the pre-frontal cortex in CMS treated rats augmented by lycopene treatment Lycopene treatment restored the antioxidant defense system by attenuating oxidative stress and increasing the anti apoptotic protein expression of Bcl 2 by maintaining mitochondrial integrity and preventing apoptosis by exhibiting the neuroprotective effect of lycopene newline newline newline