ATXN3 and autosomal dominant cerebellar ataxia: Furthermore, BP reduces neuron cell loss in an animal model of spinocerebellar ataxia (SCA) by regulating autophagy, and reduce the excitotoxicity of ataxin-3 (ATXN3) on Purkinje progenitor cells from SCA3 patient-derived iPSCs by inhibiting the activity of the calcium-activated proteolytic enzyme calpain [36,37].