EVALUATION OF ANTIDEPRESSANT ACTIVITY OF ETHANOLIC EXTRACT OF LAGERSTROEMIA SPECIOSA LEAVES IN ALBINO WISTAR RATS

Abstract

Objective: The objective of the study was to evaluate the antidepressant activity of ethanolic extract of dried leaves of Lagerstroemia speciosa L. (EELS) on acute restraint stress (ARS)-induced depression-like behavior and biochemical alterations in albino Wistar rats. Methods: Thirty rats were randomly divided into five experimental groups. Group-I (normal control) rats received normal saline (2.0 ml/kg, p.o.) daily for 14 days; Group-II (stress control) rats received normal saline (2.0 ml/kg, p.o.) daily for 14 days and subjected to restraint stress on the 13th day. Group-III (standard drug-treated) rats received imipramine (15 mg/kg, p.o.) daily for 14 days and subjected to restraint stress on the 13th day. Groups-IV and V rats were treated with EELS (100 mg/kg and 300 mg/kg, p.o.) daily for 14 days subjected to ARS on the 13th day. Stress-like behavior was assessed by subjecting the rats to behavioral paradigms such as tail-suspension test (TST) and open field test (OFT), 40 min post-restraint stress procedure. Pretest of 10 min for forced swim test (FST) was also given to each rat simultaneously. Then, 23.5 h later, the relevant samples were administered and the main test performed 30 min later. Oxidative stress parameters such as superoxide dismutase (SOD), catalase (CAT), malondialdehyde (MDA), and extent of lipid peroxidation (LPO) were analyzed in restraint stress-induced animals and control group, following FST on the 15th day. Statistical Analysis: Expression of data was done as a mean standard error of the mean. The normally distributed data were subjected to one-way analysis of variance followed by Dunnett’s test. *p<0.05 was considered statistically significant. Results: It was observed that L. speciosa L. showed a significant dose-dependent decrease in duration of immobility time in TST and FST when compared with the control group in a dose-dependent manner. The results of OFT also showed a dose-dependent increase in locomotor activity. In addition to behavioral tests, EELS also normalized oxidative stress markers such as CAT, SOD, MDA, and LPO in a dose-dependent manner. Conclusion: The results suggest that the ethanolic extract of L. speciosa L. leaves possesses significant antidepressant property, may be recommended as a supplement for the antidepressant activity.