Anxiolytic effects of aqueous extract of Hiptis spicigera Lam (Lamiaceae) in mice on chronic immobilisation and physical activity test

Abstract

The Anxiety disorders are considering as serious problems in our society life like family environment, school and work functioning. They increase the risk of other psychiatric disorders pathologies, including depression, drug and alcohol abuse and the incidence of suicide. For ameliorate this situation, anxiolytic and hypnotic substances like benzodiazepines, barbiturates and their relatives compounds are very regularly prescribed. However, the frequent use of tranquillizers and psychotropic compounds involve the variety in autonomic, endocrine, allergic, and neurological side effects. So, anxiety disorders are reveled as the world health problem. This study aims at assessing the combined of anxiolytic effect of the decoction of dried Hypstis spicigera leaves and aerobic physical activity in white mice. For this purpose, the Elevated Plus Maze test (EPM) and the Open Field (OF) test were used. Thirty male and female mice of approximately eight weeks of age and 23 g body weight were used. They were divided into seven groups of five animals each. The first one normal group received distilled water (per os), a negative control group received distilled water by oral way and underwent anxiety induction and a positive control group received diazepam intraperitoneally and underwent anxiety induction and physical activity. Then, four groups received different concentration of decoction of Hypstis spicigera by oral way, followed by chronic immobilisation stress and physical activity. Thus, the results of the EPM showed that chronic stress caused a significant decrease (p<0.001 ) of the percentage of time spent in the open arms from 42.93% in the normal control mice to 14.79% in the negative control group. Similarly, Hyptis spicigera lam decoction and physical activity induced a significant (p<0.001) increase of this percentage from 14.79% in the negative control group to 82.52% of the 225 mg/kg dose group. The diazepam also induced a significant (p<0.001) increase of this percentage. Those from the open field showed that chronic stress caused a significant (p<0.001) decrease in the amount of time spent in the centre from 4.8±0.83 s in the normal control mice to 1.2±0.44 s in the negative control group. Similarly, Hyptis spicigera Lam decoction and physical activity induced a significant (p<0.001) increase of time spent from 1.2±0.44 s in the 225 mg/kg dose group in the negative control group to 15±1s in the 225mg/kg dose group. Diazepam also induced a significant (p<0.001) increase of this time. Hyptis spicigera Lam decoction and physical activity have anxiolytic activity. Reason is why this plant is used more in traditional medicine.