Cognitive Decline and Mood Alterations in the Mouse Model of Spinocerebellar Ataxia Type 2

Spinocerebellar ataxia type 2 (SCA2) is a hereditary disorder, caused by an expansion of polyglutamine in the ataxin-2 protein. Although the mutant protein is expressed throughout all the cell and organ types, the cerebellum is primarily affected. The disease progression is mainly accompanied by a decline in motor functions. However, the disturbances in cognitive abilities and low mental state have also been reported in patients. Recent evidence suggests that the cerebellar functionality expands beyond the motor control. Thus, the cerebellum turned out to be involved into the language, verbal working, and spatial memory; executive functions such as working memory, planning, organizing, and strategy formation; and emotional processing. Here, we used the transgenic SCA2-58Q mice to evaluate their anxiety, cognitive functions, and mood alterations. The expression of the mutant ataxin-2 specifically in the cerebellar Purkinje cells (PCs) in SCA2-58Q mice allowed us to study the direct involvement of the cerebellum into the cognitive and affective control. We determined that SCA2-58Q mice exhibit anxiolytic behavior, decline in spatial memory, and a depressive-like state. Our results support the idea of cerebellar involvement in cognitive control and the handling of emotions.

Automated summary

Spinocerebellar ataxia type 2 (SCA2) is a hereditary disorder caused by an expansion of polyglutamine in the ataxin-2 protein. Although primarily affecting the cerebellum, recent evidence suggests that SCA2 also impacts cognitive abilities and emotional processing. Through the use of transgenic SCA2-58Q mice, researchers found that the mutant ataxin-2 protein expressed in cerebellar Purkinje cells led to anxiolytic behavior, decline in spatial memory, and depressive-like state. These findings support the involvement of the cerebellum in cognitive control and emotional regulation.