The effect of Melissa officinalis hydroalcoholic extract on anxiety-like behavior and hippocampal oxidative stress markers in aged mice

Abstract

Melissa officinalis is widely used to reduce anxiety levels. The aim of this study is investigation of the effect of Melissa officinalis hydroalcoholic extract on anxiety-like behavior and hippocampal oxidative stress markers in aged mice. Materials and Methods: This study was conducted experimentally on laboratory animals at the Neuroscience Research Center of Tabriz University of Medical Sciences in 2022. In this study, 45 small albino male laboratory mice were used in the weight range of 28-30 grams. Based on defined entry and exit criteria, rats were divided into 3 groups of 15 including: 1- young control group that received 0.9 normal saline daily, 2- old control group that received 0.9 normal saline daily, 3: the old group receiving 150 mg per kilogram of body weight of Melissa officinalis hydroalcoholic extract. One day after the end of the drug administration period (14 days), behavioral tests including elevated maze and open field tests were performed to evaluate anxiety behaviors. By taking blood from the left ventricle, the amount of serum corticosterone was measured. Oxidative stress indices including Total Antioxidant Capacity (TAC), Superoxide Dismutase (SOD), Glutathione Peroxidase (GPX) and Malondialdehyde (MDA) were measured. Results: In this study, Melissa officinalis extract in the group of old mice that received it caused a significant increase in the percentage of time spent in the open field compared to the group of old mice that received normal saline (P<0.05). In the group of old mice receiving Melissa officinalis compared to the group of old mice receiving normal saline, the percentage of entering the open field increased significantly (P<0.01). The amount of motor activity in the group of old mice receiving Melissa officinalis compared to the group of old mice receiving normal saline did not show a significant difference (P>0/05). The administration of Melissa officinalis in the group of old mice caused a significant increase in the time spent in the central area compared to the group of old mice receiving normal saline (P<0.01). The level of TAC and SOD in the group of old mice receiving Melissa officinalis increased significantly compared to the group of old mice receiving normal saline (P<0.05); On the other hand, the level of MDA in the group of old mice receiving Melissa officinalis had a significant decrease compared to the group of old mice receiving normal saline (P<0.01). But the level of GPX in the group of old mice receiving Melissa officinalis was not significantly different compared to the group of old mice receiving normal saline (P>0/05).