title: Antipsychotic activity of standardized Bacopa extract against ketamine-induced experimental psychosis in mice: Evidence for the involvement of dopaminergic, serotonergic, and cholinergic systems.
abstract: BACKGROUND
  Schizophrenia is a chronic disabling psychiatric disorder affecting 1% of the population worldwide. Due to the adverse effects of available antipsychotic medications, recent investigations have focused on the search for well-tolerated, safe molecules from natural resources to control the severity and progression of schizophrenia.
  
  
  OBJECTIVE
  To screen the standardized extract of Bacopa monniera Linn. (Scrophulariaceae) (BM) for its antipsychotic potential in the ketamine-induced psychosis model with mice.
  
  
  METHODS
  Graded dose of BM (40, 80, and 120 mg/kg, p.o.) were given to the mice 1 h prior to ketamine administration and tested for positive symptoms and cognitive deficits. A chronic ketamine treatment regimen was used to study the effect of BM on negative symptoms such as immobility enhancement. Each mouse was used once for the behavioral studies.
  
  
  RESULTS
  BM reduced ketamine-induced hyperactivity with an EC50 value of 76.60 mg/kg. The 80 mg/kg dose was used for all other behavior analysis. Pretreatment with BM at 80 mg/kg showed two-fold increases in transfer latency time (TLT) in passive avoidance task. Chronic BM pretreatment (80 mg/kg p.o. daily × 10 d) ameliorated the ketamine-induced enhanced immobility effect by 21% in the forced swim test. BM treatment reversed ketamine-induced increase in monoamine oxidase activity in both cortex and striatum and normalized the acetylcholinesterase activity and the glutamate levels in the hippocampus.
  
  
  CONCLUSIONS
  Overall our findings suggest that BM possesses antipsychotic properties which might be due to its modulatory action on dopamine, serotonin, and glutamate neurotransmission.
authors: Division of Pharmacology, CSIR - Central Drug Research Institute , Lucknow , India .
authors: Manavi
authors: M
authors: Chatterjee
authors: Rajkumar
authors: R
authors: Verma
authors: Reena
authors: R
authors: Kumari
authors: Seema
authors: S
authors: Singh
authors: Anil Kumar
authors: AK
authors: Verma
authors: Anil Kumar
authors: AK
authors: Dwivedi
authors: Gautam
authors: G
authors: Palit
mesh_terms: D000818:Animals; D014150:Antipsychotic Agents / Q000302:isolation & purification / Q000627:therapeutic use*; D034681:Bacopa; D004298:Dopamine / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D005973:Glutamine / Q000378:metabolism*; D007649:Ketamine / Q000633:toxicity; D008297:Male; D051379:Mice; D010936:Plant Extracts / Q000302:isolation & purification / Q000627:therapeutic use; D011618:Psychotic Disorders / Q000188:drug therapy / Q000378:metabolism*; D012701:Serotonin / Q000378:metabolism*
chemical_list: D014150:Antipsychotic Agents; D010936:Plant Extracts; D005973:Glutamine; D012701:Serotonin; D007649:Ketamine; D004298:Dopamine
keywords: Bacopa monniera; forced swim test; locomotor activity; neurotransmitter; passive avoidance test