Spatial memory impairment is associated with oxidative stress, neurodegeneration and abnormalities neuromorphology in the hippocampus of rotenone-induced Parkinson’s mouse model: neuroprotective role of a specialized Bacopa monnieri extract (CDRI-08)

Abstract

Parkinson's disease (PD), a neurodegenerative disorder linked with ageing, is associated with both motor and non-motor problems. Memory loss is a common non-motor symptom of PD, particularly as the disease progresses, and it can lead to cognitive impairment.The objective of this study was to investigate the underlying biochemical, molecular, and neuroanatomical pathways that contribute to learning and memory impairment in PD. The study investigates the potential neuroprotective and neurotherapeutic effects of the Bacopa monnieriextract (CDRI-08), a natural nootropic medication, on memory deterioration associated with PD. To comprehend the information provided, we developed a PD mouse model by administering rotenone subcutaneously at a dose of 2mg/kg BW. Spatial working memory and the expression of α-Synuclein in the hippocampus was examined. Additionally, evaluation of the oxidative stress parameters, neuronal cell density, apoptosis in subregions of the hippocampus, and dendritic arborization and dendritic spine density in CA1 pyramidal neurons of the hippocampus. Results showed that PD exhibited a decline in their ability to remember spatial information, which can be correlated with high oxidative stress characterized by increased reactive oxygen species and lipid peroxidation levels whereas decreased activity of SOD and catalase. This oxidative stress resulted in a drop in the density of neurons due to increased cell death characterized by increased caspase-3 expression and TUNEL-positive cells, leading to a loss of dendritic length, branching, and dendritic spine density. Administering BME (CDRI-08) orally effectively alleviates the illness and additionally improves neuroprotection by strengthening and nourishing neurons by increasing the activity of antioxidant enzymes and decreasing the expression of pro-apoptotic factor caspase-3. Collectively, these findings indicate that Bacopa monnieri extract can be utilized as a herbal remedy to treat memory impairment induced by PD.