Inhibitory Effect of Bacopasides on Spontaneous Morphine Withdrawal Induced Depression in Mice

Bacopa monnieri is a perennial herb with a world known image as a nootropic. We investigated the effect of Bacopa monnieri methanolic extract (Mt Ext BM) 10, 20, and 30 mg/kg body weight (b.w) on acquisition and expression of morphine withdrawal induced depression in mice. Locally available Bacopa monnieri (BM) was screened for contents of Bacoside A₃, Bacopasaponin C, and Bacopaside II using HPLC with UV. Morphine dependence was induced in mice using twice daily escalating chronic morphine treatments (20–65 mg/kg b.w) for eight consecutive days. Morphine withdrawal induced depression was assayed in animals using forced swimming test (FST), three days after last morphine injection. The HPLC analysis revealed that Mt‐ext BM contained Bacoside A₃ as major component, i.e. 4 µg in each mg of extract. The chronic treatment with Met Ext BM 10, 20, and 30 mg/kg b.w. dosing significantly inhibited opioid withdrawal induced depression in mice. These findings imply a newer potential role of Bacopa monnieri in the clinical management of opioid withdrawal induced depression which can be attributed to Bacoside A₃. Copyright © 2013 John Wiley & Sons, Ltd.