Antidepressant and anxiolytic activity of Lavandula officinalis aerial parts hydroalcoholic extract in scopolamine-treated rats

Abstract

Context: Anxiety and depression are common in Alzheimer’s disease (AD). Despite some evidence, it is difficult to confirm Lavandula officinalis Chaix ex Vill (Lamiaceae) as an anxiolytic and antidepressant drug.

Objective: The effects of L. officinalis extract were studied in scopolamine-induced memory impairment, anxiety and depression-like behaviour.

Materials and methods: Male NMRI rats were divided into control, scopolamine alone-treated group received scopolamine (0.1 mg/kg) intraperitoneally (i.p.), daily and 30 min prior to performing behavioural testing on test day, for 12 continuous days and extract pretreated groups received aerial parts hydro alcoholic extract (i.p.) (100, 200 and 400 mg/kg), 30 min before each scopolamine injection. Memory impairment was assessed by Y-maze task, while, elevated plus maze and forced swimming test were used to measure anxiolytic and antidepressive-like activity.

Results: Spontaneous alternation percentage in Y maze is reduced by scopolamine (36.42 ± 2.60) (p ≤ 0.001), whereas lavender (200 and 400 mg/kg) enhanced it (83.12 ± 5.20 and 95 ± 11.08, respectively) (p ≤ 0.05). Also, lavender pretreatment in 200 and 400 mg/kg enhanced time spent on the open arms (15.4 ± 3.37 and 32.1 ± 3.46, respectively) (p ≤ 0.001). On the contrary, while immobility time was enhanced by scopolamine (296 ± 4.70), 100, 200 and 400 mg/kg lavender reduced it (193.88 ± 22.42, 73.3 ± 8.25 and 35.2 ± 4.22, respectively) in a dose-dependent manner (p ≤ 0.001).

Discussion and conclusion: Lavender extracts improved scopolamine-induced memory impairment and also reduced anxiety and depression-like behaviour in a dose-dependent manner.

Keywords:

• Memory impairment
• Y maze
• elevated plus maze
• forced swimming
• depression
• anxiety

Acknowledgements

The authors would like to thank Ms. Herbod for technical assistance, the Herbal Processing Center of Jihad Daneshgahi (Mr. Mahboob Habibzadeh) for GC/MS analysis and Seyed Behrooz Nasihatkon for paper editing. Special thanks to Neurophysiology Research Center of Shahed University for the needful fund of the current research. We are also grateful to the department of pharmacognosy, faculty of pharmacy, Tehran university of medical sciences (Dr. Mahdi Vazirian) for Phytochemical screening and also the department of biology, faculty of basic sciences, Shahed university (Dr. Tayyebeh Radjabian) for HPLC analysis.

Disclosure statement

There is no conflict of interest for this article.

Additional information

Funding

This work was financially funded and supported by a research grant from Neurophysiology Research Center of Shahed University (Tehran, Iran).