Cognitive impairment is a debilitating symptom of schizophrenic patients causing functional disability. Neither typical nor atypical antipsychotic drugs are able to control it. There is a strong potential that Bacosides A and B from the plant Bacopa monnieri (Brahmi) could be a novel neuroprotective compound for the prevention of cognnitive deficits in schizophrenia.

To study neuroprotective effects of Brahmi on novel object recognition tasks and the cerebral VGLUT2 density in rat models that are schizophrenia induced through sub-chronic phencyclidine (PCP) administration.

Rats were divided into 3 groups; Group-A: Control; Group-B: PCP and Group-C: Bacosides A and B + PCP. Discrimination ratio (DR) representing cognitive ability was obtained from novel object recognition test. VGLUT2 density was measured in prefrontal cortex, striatum, cornu ammonis fields 1 (CA1) 2/3 (CA2/3) of hippocampus using immunohistochemistry.

DR in the PCP-group was significantly decreased compared with the control group. This occurred alongside reduced VGLUT2 in the cingulate gyrus. Bacosides A and B + PCP group showed a significant increase in DR score compared with PCP alone. This occurred alongside a significant increase in VGLUT2 in the cingulate gyrus.

Cognitive deficit observed in rats receiving PCP administration was mediated by VGLUT2 reduction in the cingulate gyrus. Administration of Bacosides A and B before PCP administration can restore this cognitive deficit by increasing VGLUT2 density in this brain area to normal level. Conclusively, Bacosides A and B could be a novel neuroprotective compound for prevention of cognitive deficits in schizophrenia.