Bacopa monnieri Extract Offsets Rotenone-Induced Cytotoxicity in Dopaminergic Cells and Oxidative Impairments in Mice Brain

Bacopa monnieri (BM), an ayurvedic medicinal
herb is widely known for its memory enhancing ability
and improvement of brain function. In this study, we tested
the hypothesis that BM extract (BME) could offset neurotoxicant-
induced oxidative dysfunctions in developing
brain in a rotenone (ROT) mouse model. Pretreatment of
dopaminergic (N27 cell lines) cells with BME exhibited
significant cytoprotective effect as evidenced by the
attenuation of ROT-induced oxidative stress and cell death.
Further, the neuroprotective efficacy of BME was assessed
in prepubertal mice administered ROT (i.p. 1.0 mg/kg
b.w./day) for 7 days. BME treatment significantly offset
ROT-induced oxidative damage in striatum (St) and other
brain regions as evident by the normalized levels of oxidative
markers (malondialdehyde, ROS levels, and hydroperoxides)
and restoration of depleted GSH levels. Further,
BME effectively normalized the protein carbonyl content
in all brain regions suggesting its ability to prevent protein
oxidation. Furthermore, BME treatment restored the
activity levels of cytosolic antioxidant enzymes, neurotransmitter
function, and dopamine levels in St. Based on
our findings, we hypothesize that the neuroprotective
effects of BM extract may be at least in part related to its
ability to enhance reduced glutathione and antioxidant
defenses in brain regions. It is suggested that BM may be
effectively exploited as a prophylactic/therapeutic adjuvant
for neurodegenerative disorders involving oxidative stress.