RESEARCH ARTICLE Reduction in Subventricular Zone-Derived Olfactory Bulb Neurogenesis in a Rat Model of Huntington’s Disease Is Accompanied by Striatal Invasion of Neuroblasts

Huntington’s disease (HD) is an inherited progressive neurodegenerative disorder caused by an expanded CAG repeat in exon 1 of the huntingtin gene (HTT). The primary neuropa-thology of HD has been attributed to the preferential degeneration of medium spiny neurons (MSN) in the striatum. Reports on striatal neurogenesis have been a subject of debate; nev-ertheless, it should be considered as an endogenous attempt to repair the brain. The sub-ventricular zone (SVZ) might offer a close-by region to supply the degenerated striatum with new cells. Previously, we have demonstrated that R6/2 mice, a widely used preclinical model representing an early onset HD, showed reduced olfactory bulb (OB) neurogenesis but induced striatal migration of neuroblasts without affecting the proliferation of neural pro-genitor cell (NPCs) in the SVZ. The present study revisits these findings, using a clinicall