Dimethyl Fumarate Exerts a Neuroprotective Effect by Enhancing Mitophagy via the NRF2/BNIP3/PINK1 Axis in the MPP+ Iodide-Induced Parkinson's Disease Mice Model.

Background: Parkinson's disease (PD) is a progressive neurodegenerative disorder linked to the loss of dopaminergic neurons in the substantia nigra. Mitophagy, mitochondrial selective autophagy, is critical in maintaining mitochondrial and subsequently neuronal homeostasis. Its impairment is strongly implicated in PD and is associated with accelerated neurodegeneration.

Objective: To study the positive effect of dimethyl fumarate (DMF) on mitophagy via the NRF2/BNIP3/PINK1 axis activation in PD disease models.

Methods: The neuroprotective effect of DMF was explored in in vitro and in vivo PD models. MTT assay was performed to determine the DMF dose followed by JC-1 assay to study its mitoprotective effect in MPP⁺ exposed SHSY5Y cells. For the in vivo study, C57BL/6 mice were divided into six groups: Normal Control (NC), Disease Control (DC), Sham (Saline i.c.v.), Low Dose (MPP⁺ iodide+DMF 15 mg/kg), Mid Dose (MPP⁺ iodide+DMF 30 mg/kg), and High Dose (MPP⁺ iodide+DMF 60 mg/kg). The neuroprotective effect of DMF was assessed by performing rotarod, open field test, and pole test, and biochemical parameter analysis using immunofluorescence, western blot, and RT-PCR.

Results: DMF treatment significantly alleviated the loss of TH positive dopaminergic neurons and enhanced mitophagy by increasing PINK1, Parkin, BNIP3, and LC3 levels in the MPP⁺ iodide-induced PD mice model. DMF treatment groups showed good locomotor activity and rearing time when compared to the DC group.

Conclusions: DMF confers neuroprotection by activating the BNIP3/PINK1/Parkin pathway, enhancing the autophagosome formation via LC3, and improving mitophagy in PD models, and could be a potential therapeutic option in PD.