Pridopidine Mediated Sigma-1 Receptor Activation and Therapeutic Implications in Neurodegenerative Diseases

Neurodegenerative diseases are targets for pridopidine therapy, which aims to improve quality of life through neuroprotective mechanisms that involve sigma-1 receptor (S1R) activation. Neurodegenerative motor and cognitive diseases are influenced by dopamine imbalance, where disruptions in pathways contribute to states that are hyperkinetic or hypokinetic, while current dopaminergic treatments are symptomatic rather than disease-modifying, especially for Huntington's disease and Amyotrophic lateral sclerosis. This review summarizes the mechanisms underlying pridopidine-mediated neuroprotection and examines the current evidence supporting its therapeutic potential. The S1R is an endoplasmic reticulum-mitochondria-associated chaperone involved in homeostasis of calcium, stress regulation, and mitochondrial function. Pridopidine is a small lipophilic molecule that crosses the blood-brain barrier and acts as an S1R agonist, with minimal dopamine D2 receptor occupancy. Activation of S1R by pridopidine modulates calcium signaling and enhances anti-apoptotic activity. Collectively, available evidence suggests that pridopidine may improve motor outcomes and slow disease progression in Huntington's disease and amyotrophic lateral sclerosis, supporting its promise as a disease-modifying therapeutic strategy.