Non-invasive Neuromodulation in MPTP-induced Parkinson’s Mice Model.

Abstract

Transcranial direct current stimulation (tDCS) is connected with change in NMDA receptor movement either increase or decrease in their activity and change in cortical blood stream. Therefore, repeated tDCS of the brain with Parkinson’s disease (PD) will induce the functional and histological changes as well as changes in EEG activity. 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) (30 mg/kg; i.p injection) was used for inducing PD in mice model. Twelve Balb/c mice were used in this study, which were allocated to 4 groups namely the control group (n=3), tDCS group (n=3) receiving tDCS treatment only, MPTP group (n=3) given MPTP injection of 30 mg/kg, and MPTP plus tDCS group (n=3) having both MPTP injection and tDCS treatment. Schedule for both MPTP and tDCS-treatment schedule comprised of 5-days. Grid walking test, and swim test scores were checked at different days postoperatively. Cup electrodes were used for tDCS treatment as well as EEG recordings. EEG of each mice was taken on the 5th day. After the experiments, mice were sacrificed for the evaluation of histological changes (changes of neuronal cells). The results shows that the MPTP plus tDCS group showed improvement of grid walking and swim test scores at 5th day of tDCS treatment postoperatively. Significant increase in β-activity was seen in MPTP group whereas after the tDCS treatment significant decrease in β-activity towards the normal condition was seen in MPTP plus tDCS group. During histological analysis, well preserved neurons were seen in MPTP plus tDCS group. From these results, it could be inferred that repeated tDCS have a preventive effect on dopaminergic neurons in MPTP-induced PD mice model.