Evaluation of Neuroprotective Effects of Polymeric Berberine Nanoparticles Against Parkinson’s Rat Model

Parkinson’s disease is triggered by various factors, leading to the irreversible decrease of dopaminergic neurons in the region of substantia nigra (SNpc) which causes motor-related symptoms. There is evidence that oxidative stress and apoptosis have a role in the neurodegenerative alterations seen in Parkinson’s disease (PD). Berberine is an isoquinoline alkaloid found naturally in plants and presents multiple pharmacological effects. However, its application is limited due to low solubility, bioavailability, and high metabolism. To increase the therapeutic benefit of berberine, we formulated berberine-loaded polymeric nanoparticles for better brain delivery and improved residence time. Our study demonstrates the neuroprotective effect of polymeric berberine nanoparticles (BBR NPs) in a rotenone-induced Parkinson’s rat model. Rats were administered daily with berberine (BBR) and berberine nanoparticles (BBR NPs) for 21 days and also received rotenone 1 h after treatment, continuously for 21 days. Motor impairments were assessed on day 22. When evaluated for grip strength, spontaneous locomotion, and rotarod skills, the rats in the rotenone group revealed motor dysfunction. Histopathological studies, biochemical parameters, and apoptotic markers were performed which were significantly reversed in groups treated with BBR NPs. Moreover, apoptotic markers and histopathological investigations showed rotenone-administered rats demonstrated damaged neurons. However, BBR NPs lessened the reduction of neuronal cells in the substantia nigra and decreased the apoptotic markers in rotenone-treated rats. These results indicate that BBR NPs have the potential to improve motor impairments induced in the rotenone-induced Parkinson’s rat model at a low dose as compared to berberine alone.