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Sensory ataxia and cardiac hypertrophy caused by neurovascular oxidative stress

ABSTRACT: In our chemogenetic neurovacular mouse model, DRGs transcriptomic analysis was performed by RNA-seq; Oxidative stress is associated with cardiovascular and neurodegenerative disease. We created transgenic chemogenetic mouse lines expressing yeast D-amino oxidase (DAAO) in endothelial cells and neurons. DAAO generates hydrogen peroxide (H2O2) in target tissues when mice are provided with D-amino acids, causing oxidative stress. DAAO-TGCdh5 transgenic mice express DAAO under control of the putatively endothelial-specific Cdh5 promoter. We provided these mice with D-alanine¬– expecting a vascular phenotype– but found that the mice develop sensory ataxia and neurodegeneration in dorsal root ganglia (DRG), associated with transgene expression within DRG neurons; electron microscopy revealed distorted mitochondria. DAAO-TGCdh5 mice also develop cardiac hypertrophy in response to chemogenetic oxidative stress, and we discovered transgene expression in parasympathetic nodose ganglia innervating the heart. We developed and characterized another transgenic line expressing DAAO under control of a different endothelial cell-specific Tie2 promoter. DAAO-TGTie2 mice express the transgene in endothelium but not neurons, and develop neither ataxia nor cardiac hypertrophy. The combination of ataxia, mitochondrial dysfunction, and cardiac hypertrophy is similar to findings in patients with Friedreich's Ataxia. Our observations confirm that neurovascular oxidative stress is sufficient to cause sensory ataxia and cardiac hypertrophy, and identify the DAAO-TGCdh5 mouse as a potentially informative animal model for Friedreich’s Ataxia.

ORGANISM(S): Mus musculus

PROVIDER: GSE229143 | GEO | 2023/05/01

REPOSITORIES: GEO

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Sensory ataxia and cardiac hypertrophy caused by neurovascular oxidative stress

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