Molecular pathogenesis, experimental models and new therapeutic strategies for Parkinson's disease.

Parkinson's disease (PD) is a progressive neurodegenerative disorder characterized by rigidity, bradykinesia, postural instability and resting tremor. The major symptoms are related to the progressive loss of dopaminergic neurons in the substantia nigra pars compacta. The recent discovery of PARK genes causing familial forms of PD has led to a new approach in the study of the disease. The cause and pathogenesis of PD remains unknown; mitochondrial dysfunction, oxidative damage, endoplasmic reticulum stress, failure of the ubiquitin-proteasome system, environmental factors and genetic predisposition might all be involved. Toxin-induced PD animal models and genetic mouse models that mimic familial PD have contributed to investigating the molecular pathogenesis and treatment of the disease. Recently, neurogenesis in the striatum and subventricular zones in PD animal models have been reported. This review discusses molecular pathogenesis, experimental disease models and recent cell-based therapeutic approaches for PD.