A Natural Phenolic Compound Quercetin Showed the Usefulness by Targeting Inflammatory, Oxidative Stress Markers and Augment 5-HT Levels in One of the Animal Models of Depression in Mice.

AIM: In the present study quercetin was studied for its role in inflammation, oxidative stress markers and 5-HT levels in unpredictable chronic mild stress (UCMS) animal model of depression.

MATERIALS AND METHODS: The mice were randomized into different groups trained for UCMS protocol followed by different drug treatments. Treatments were started after 2 weeks from the start of UCMS protocol and continued up to 6 weeks. The behavioral tests such as modified forced swimming (MFST), tail suspension (TST) and open field tests were performed on week 6, at least 24 h after the last drug treatment. Behavioral tests were preceded following animal sacrifice for biochemical estimations.

RESULTS: A significant decrease in swimming, climbing times and increase in immobility time in MFST and TST was observed in UCMS group. Administration of quercetin (25 mg/kg per orally (p.o) reversed these times in MFST and TST. A decrease in no. of field crossing, time spent in centre and no. of rearing were observed in UCMS group. Quercetin reduced these observations in open field test. There was a decrease in superoxide dismutase (SOD), glutathione (GSH), catalase and 5 HT levels in the brain tissue. Quercetin treatment significantly augmented SOD, GSH, catalase and 5 HT levels. Glutamate, TNF-α and IL-6 levels were increased in UCMS group while quercetin decreased these cytokines.

CONCLUSION: Quercetin resulted antidepressant-like effect by its antioxidant, anti-inflammatory activities, reduced excitotoxicity and augmented 5 HT levels. This pointed out the usefulness of this phenolic compound as adjuvent drug along with other antidepressant drugs.