Experience of experimental modelling of Huntington’s disease

Resumo

Huntington’s disease (HD) is an autosomal dominant neurodegenerative disorder characterized by choreic involuntary movements, decline in cognitive functions, behavioral disturbances, and progressive neuronal death affecting primarily the striatum. The fatal nature of HD makes it important to search for new effective methods of its treatment, which requires the development of experimental models of the disease. These models can be created using 3-nitropropionic acid (3-NPA), which is a neurotoxin causing typical changes in motor skills and memory impairment in animals due to induction of oxidative stress, impaired glutathione defense, and destruction of striatal cells. We modeled HD in rats by chronic daily intraperitoneal administration of 3-NPA for 17 days. Systemic administration of a low dose of 3-NPA (10 mg/kg) induced hyperactivity of animals in the open field test (including movement redundancy as a hyperkinesia analogue) and had no effect on the behavior of the animals in the X-maze test. On the contrary, rats administered with a toxic dose of 3-NPA (20 mg/kg) exhibited a significant decrease in their motor activity and a cognitive decline in behavioral tests. A histopathological analysis revealed damage and loss of neurons and a decrease in expression of dopaminergic markers (tyrosine hydroxylase and plasma membrane dopamine transporter) in the striatum. The gliotoxic effect of 3-NPA was also found in the striatum, which was confirmed by immunohistochemical staining for astrocytic proteins: GFAP, glutamine synthetase, and aquaporin-4. This HD model may be helpful for testing new experimental therapies at different stages of HD-like neurodegeneration, including therapies based on cell neurotransplantation.