Modeling of the Progressive Degradation of the Nigrostriatal Dopaminergic System in Mice to Study the Mechanisms of Neurodegeneration and Neuroplasticity in Parkinson's Disease

The fight against neurodegenerative diseases, including Parkinson's disease (PD), is among the global challenges of the 21st century. The low efficiency of therapy is due to the late diagnosis and treatment of PD, which take place when there is already significant degradation of the nigrostriatal dopaminergic system, a key link in the regulation of motor function. We have developed a subchronic mouse model of PD by repeatedly administering 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) at gradually increasing doses with a 24 h interval between injections, a period comparable to the time of MPTP metabolism and elimination from the body. This model reproduces the main hallmarks of PD: progressive degeneration of dopaminergic neurons; the appearance of motor disorders with a 70-80% decrease in the level of dopamine in the striatum; an increase in dopamine turnover in the striatum to compensate for dopamine deficiency. When comparing the degradation of the nigrostriatal dopaminergic system and motor disorders in mice in the acute and subchronic models of PD, it has turned out that the resistance of dopaminergic neurons to MPTP increases with its repeated administration. Our subchronic model of PD opens up broad prospects for studying the molecular mechanisms of PD pathogenesis and developing technologies for early diagnosis and preventive treatment.