Antipsychotic Property of Methanol Crude Extract of Peperomia pellucida (L) Kunth. (Piperaceae) Whole Plant against Ketamine Induced Psychosis in Mice

Abstract

Medicinal plants have been discovered and used in traditional medicine practice since prehistoric times. Numerous plants contain diverse phytochemicals and possess pharmacological actions, many of which remain unassessed by rigorous scientific research of defined efficacy and safety. This study evaluated the antipsychotic activity of Peperomia pellucida methanol crude extract against ketamine induced psychosis in Swiss albino mice. The preliminary phytochemical analysis was carried out following standard procedures, while stereotypy test, Y-maze test, object recognition and forced swim test (FST), were the behavioral models used for the antipsychotic study. The Histopathology of the mice brain was also carried out. Statistical analysis was done using one-way ANOVA followed by Dunnett’s post hoc test and p < 0.05 was considered significant. Phytochemical analysis revealed the presence of saponins, tannins, flavonoids and alkaloids in the pulverized plant. The crude extract at 125 mg\kg reduced stereotype behavior in Ketamine-induced mice. The extract enhanced cognition in the animals by producing a significant dose-dependent decrease in the number of alternate arm entries and increases the time spent in recognizing a novel object compared to the negative control. In the FST model, 500 mg\kg was more effective in decreasing immobility as compared to negative control. The histopathology of the mice brain showed that the extract at the dose of 500 mg/kg produced a similar effect to the standard drug and at 250 mg/kg produced a regenerative effect on brain of the mice. The results established that Peperomia pellucida possesses antipsychotic property against positive, negative and cognitive symptoms of psychosis.