Purkinje Neuron Ca2+ Influx Reduction Rescues Ataxia in SCA28 Model
- UNCP Author/Contributor (non-UNCP co-authors, if there are any, appear on document)
- Dr . Ben Bahr, William C. Friday Chair and Professor of Molecular Biology and Biochemistry (Creator)
- Institution
- The University of North Carolina at Pembroke (UNCP )
- Web Site: http://www.uncp.edu/academics/library
Abstract: Spinocerebellar ataxia type 28 (SCA28) is a neurodegenerative disease caused by mutations of the mitochondrial proteaseAFG3L2. The SCA28 mouse model, which is haploinsufficient for Afg3l2, exhibits a progressive decline in motor functionand displays dark degeneration of Purkinje cells (PC-DCD) of mitochondrial origin. Here, we determined that mitochondria incultured Afg3l2-deficient PCs ineffectively buffer evoked Ca2+ peaks, resulting in enhanced cytoplasmic Ca2+ concentrations,which subsequently triggers PC-DCD. This Ca2+-handling defect is the result of negative synergism between mitochondrialdepolarization and altered organelle trafficking to PC dendrites in Afg3l2-mutant cells. In SCA28 mice, partial genetic silencingof the metabotropic glutamate receptor mGluR1 decreased Ca2+ influx in PCs and reversed the ataxic phenotype. Moreover,administration of the ß-lactam antibiotic ceftriaxone, which promotes synaptic glutamate clearance, thereby reducing Ca2+influx, improved ataxia-associated phenotypes in SCA28 mice when given either prior to or after symptom onset. Together, theresults of this study indicate that ineffective mitochondrial Ca2+ handling in PCs underlies SCA28 pathogenesis and suggest thatstrategies that lower glutamate stimulation of PCs should be further explored as a potential treatment for SCA28 patients.
Purkinje Neuron Ca2+ Influx Reduction Rescues Ataxia in SCA28 Model
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Additional Information
- Publication
- Journal of Clinical Investigation 125.1
- Language: English
- Date: 2015
- Keywords
- Purkinje Neuron, Spinocerebellar Ataxia, Neurodegenerative Disease, Treatment, SCA 28