Pharmacological Evaluation of Mentha spicata L. and Plantago major L., Medicinal Plants Used to Treat Anxiety and Insomnia in Colombian Caribbean Coast

Anxiety disorders are highly prevalent, chronic, and disabling conditions that impose enormous health and economic costs both on individuals and on society. Medicinal plants are an invaluable source of bioactive metabolites that can be useful as new pharmacological treatment. Teas from Mentha spicata and Plantago major are employed by Colombian populations to treat stress and insomnia. This work was conducted to evaluate their anxiolytic and hypnotic properties. For this, we employed the Elevated Plus-Maze test and the sodium pentobarbital-induced hypnosis method using Wistar rats. Oral administration of M. spicata extract (1000 mg/Kg) significantly increased the exploration and time spent in the open arms, which indicates its anxiolytic activity. On the other hand, both M. spicata and P. major extracts (1000 mg/Kg) remarkably augmented the sleeping time induced by pentobarbital, suggesting a sedative and hypnotic effect of the plants extracts. In addition, the acute toxicological study demonstrated that the doses used did not induce mortality or toxicity effects at hepatic or renal level. The bioactivity seems to be related to several kinds of constituents, mainly phenolic compounds such as flavonoids and tannins. In conclusion, these results reinforce the potential use of these species in the therapy of anxiety.