In recent years, Salvia officinalis has been a subject of intensive studies to document its traditional use and to find new biological effects. Numerous studies have been carried out in this contest and most of them were interested in Salvia officinalis extract’ effects and not many explored the biological activities of Salvia officinalis essential oil, especially the ones related to the central nervous system. The Purpose of this study is to investigate the acute toxicity of salvia officinalis essential oil in female Wistar rats, and to explore the antidepressant-like and anxiolytic-like effects and memory enhancing of the safe dose of this essential oil. In this experiment, salvia officinalis essential oil was administered once by oral gavage to four groups of female Wistar rats (n=6) at three different doses; 1000, 2000 and 3000 mg/kg. During 14 days after dosing, a follow-up was carried out for the mortality, food and water consumption, body weight changing and clinical signs. Biochemical parameters and organ weight were also examined. The behavior of rats was evaluated at the end of the experiment for anxiety-like and depression-like and memory. Accordingly, treatment with salvia officinalis essential oil at a dose of 2000 mg/kg showed no mortality or clinical signs, nor any changes in body, organ weights or biochemical parameters, except for mortality induced in one female rat treated with 2000 mg/kg. Furthermore, the LD50 (50% lethal dose) was determined at 3000 mg/kg. Based on these findings, the no observed adverse effect level of salvia officinalis essential oil was established to be 1000 mg/kg. Evaluation of the effect of this therapeutic dose revealed a clear anxiolytic and antidepressant actions and improved memory functioning in female Wistar rats. In conclusion, salvia officinalis essential oil produce neuroprotective activity in female rats.
Keywords | Herbal medicine, Acute toxicity, Salvia officinalis, Anxiety, Depression, Memory, Rats, Phytotherapy