Mitochondrial dysfunction and oxidative stress in Parkinson's disease: mechanisms, biomarkers, and therapeutic strategies.

Background: Parkinson's disease (PD) is the second most common neurodegenerative disorder, characterized by motor symptoms and progressive degeneration of dopaminergic neurons. Accumulating evidence indicates that mitochondrial dysfunction and oxidative stress are major contributors to PD pathogenesis.

Objectives: This review explores the molecular mechanisms underlying PD, emphasizing mitochondrial dysfunction and oxidative stress. It also examines genetic and environmental contributors, emerging biomarkers, and future treatment strategies.

Methods: An extensive literature review was conducted, focusing on mitochondrial biology, oxidative stress, genetic mutations, and environmental toxins relevant to PD. Investigations into treatment options - including redox therapies, gene therapies, and lifestyle approaches - were also examined.

Results: Mitochondrial dysfunction in PD includes disrupted oxidative phosphorylation and elevated reactive oxygen species (ROS). This also affects calcium homeostasis, especially in substantia nigra neurons. Genetic mutations (PINK1, Parkin, DJ-1, LRRK2, GBA) impair mitophagy and antioxidant defenses. Environmental toxins (e.g. MPTP, rotenone) further damage mitochondrial function and contribute to dopaminergic neuron loss. Emerging biomarkers involve measurements of lipid peroxidation and mitochondrial DNA damage. Promising therapeutic strategies include mitochondria-targeted antioxidants (e.g. MitoQ), PINK1-based gene therapy, Parkin activation, ketogenic diet, and exercise-induced mitochondrial biogenesis.

Conclusions: Mitochondrial dysfunction and oxidative stress are central to PD pathophysiology. Strategies targeting these mechanisms may slow disease progression. Future research should emphasize combination therapies and early intervention trials, alongside biomarker integration, to enhance clinical outcomes.