Evaluation of Additive or Synergistic Effect of Piper nigram and Ocimum sanctum Extracts for their Antidepressant Activity

Depression is a state of excessive sensitivity to criticism, fear of rejections, lack of self-interest, loss of pleasure. In the traditionalsystems of medicine, many plants and formulations have been used to treat depression for thousands of years. In recent times,research on the plants increased globally and so many plants provide the evidence to cure diseases. Ocimum sanctum, popularlyknown as Tulsi is one of the sacred herbs for Hindus in the Indian subcontinent. It has a versatile role in traditional medicine. Thefruits of Piper nigrum are used to make black pepper. This hotly pungent spice is one of the earliest known and most widely usedspices in the world today. Wide range of animal tests for antidepressant agents are commonly used. The Forced swim test and Tailsuspension test in mice were mostly used. Hence in the present study Forced swim test was used as animal model of depression. Inpresent study immobility time in Forced swim test was significantly decreased by a combination of Piper nigrum fruit extract andOcimum sanctum extract treated groups compared to control group. The combination of extracts (50 mg/kg each) activity wascomparable to standard drug Fluoxetine. Treatment with extracts does not modify the locomotor activity of mice, which indicatesthat they exert antidepressant effects without modifying significantly locomotor activity. Therefore, the present study confirms thecombination of alcoholic extract of Piper nigrum (AEPN) fruit and aqueous extract of Ocimum sanctum (AEOS) possessingadditive/synergistic antidepressant activity.