Evaluation of central nervous system (CNS) depressant activity of methanolic extract of Commelina diffusa Burm. in mice

Background: Commelina diffusa Burm. (Family: Commelinaceae) is usually known as “climbing dayflower or spreading dayflower” in Bangladesh. The plant is used in fever, malaria, insect, bug bites, rheumatoid arthritis, gonorrhea, influenza, and bladder infection etc. The present investigation was undertaken which deals with the evaluation of central nervous system (CNS) depressant activity of methanolic extract of C. diffusa in mice models. Methods: The central nervous system (CNS) depressant activity of C. diffusa was evaluated by the classical models of depression as open field, hole cross, forced swimming, tail suspension, and thiopental sodium induced sleeping time tests in mice. The animals were divided into control, positive control, and three test groups containing five mice each. The test groups received extract at the doses of 50, 100, and 200 mg/kg body weight orally where as the control group received distilled water (0.1 mL/mouse, p.o.). Diazepam (1 mg/kg, i.p.) was used as standard drug. Results: It is clear that the plant extract significantly decreased the locomotor activity of mice in open field and hole cross tests when compared to the control (p < 0.05). It is observed that the extract showed significantly (p < 0.05) increased in immobility time in forced swimming and tail suspension tests in mice. In addition, the extract produced prolongs the sleeping time with onset of action in contrast to the control group. Conclusions: The present work depicts the evaluation of possible CNS depressant activity of C. diffusa in mice models. The obtained results provide support for the use of this species in traditional medicine and warrants further pharmacological investigations that could lead to novel leads in future.