Oleuropein Reverses Repeated Corticosterone-Induced Depressive-Like Behavior in mice: Evidence of Modulating Effect on Biogenic Amines

Abstract

Depression is still one of challenging, and widely encountered disorders with complex etiology. The role of healthy diet and olive oil in ameliorating depression has been claimed. This study was designed to explore the effects of oleuropein; the main constituent of olive oil; on depression-like behaviors that are induced by repeated administration of corticosterone (40 mg/kg, i.p.), once a day for 21 days, in mice. Oleuropein (8, 16, and 32 mg/kg, i.p.) or fluoxetine (20 mg/kg, positive control, i.p.1) was administered 30 minutes prior to corticosterone injection. Sucrose consumption test, open-field test (OFT), tail suspension test (TST), and forced swimming test (FST) were performed. Reduced Glutathione (GSH), lipid peroxidation, and biogenic amines; serotonin, dopamine, and nor-epinephrine; levels were also analyzed in brain homogenates. Corticosterone treatment induced depression-like behaviors, it increased immobility time in the TST, OFT, and FST, decreased the number of movements in OFT, and decreased sucrose consumption. Corticosterone effect was associated with depletion of reduced glutathione and increase of lipid peroxidation, in addition to modification of biogenic amines; decreased serotonin and dopamine. Oleuropein or fluoxetine administration counteracted corticosterone-induced changes. In conclusion, oleuropein showed a promising antidepressant activity, that is evident by improving corticosterone-induced depression-like behaviors, and normalizing levels of biogenic amines.

Neuroprotective effects of oleuropein: Recent developments and contemporary research

“…These disorders are usually characterized by multiple neural disruptions such as neuroanatomical, neurotransmitter, and neuroendocrine alterations (Bandelow et al., 2017; Martin et al., 2009). The neural systems involving regulation of three major monoamine neurotransmitters such as serotonin (5‐HT) (Lawther et al., 2020), DA (Bandelow et al., 2016), and norepinephrine (NE) (Purvis et al., 2018) are the most extensively studied neural systems associated with progression of anxiety. These studies collectively summarizes that hyperactivation of noradrenergic system and under activation of serotonergic system are basically involved in pathology of anxiety (Montoya et al., 2016).…”

Alpha-terpineol: evaluation and pharmacological screening as an antidepressant agent

“…In another study, similar responses were found after treatment with oleuropein at doses of 16 and 32mg/kg, which caused a significant improvement comparable to treatment with fluoxetine (p<0.05). Oleuropein at 16 and 32 mg/kg caused a reduction of approximately 50% in immobility time compared to that of the control group (p <0.001) in FST (Badr, Attia, & Al-Rasheed, 2020).…”

A Comprehensive Phenotype of Non-motor Impairments and Distribution of Alpha-Synuclein Deposition in Parkinsonism-Induced Mice by a Combination Injection of MPTP and Probenecid

“…To assess the depression-like behaviors, we performed the tail suspension test as previously described ( Badr et al, 2020 ). The immobility is a behavioral characteristic associated with depression ( Cryan et al, 2005 ).…”