PUBLICATION
Altered Glycolysis and Mitochondrial Respiration in a Zebrafish Model of Dravet Syndrome
- Authors
- Kumar, M.G., Rowley, S., Fulton, R., Dinday, M.T., Baraban, S.C., Patel, M.
- ID
- ZDB-PUB-160412-1
- Date
- 2016
- Source
- eNeuro 3(2): e0008-16 (Journal)
- Registered Authors
- Baraban, Scott, Dinday, Matthew
- Keywords
- Dravet syndrome, epilepsy, glycolysis, metabolism, mitochondrial respiration, zebrafish
- MeSH Terms
-
- Zebrafish
- Animals, Genetically Modified
- Potassium Channel Blockers/pharmacology
- Animals
- Glycolysis/drug effects
- Glycolysis/genetics*
- Disease Models, Animal
- Histocompatibility Antigens/metabolism
- Mutation/genetics
- Statistics, Nonparametric
- Gene Expression Regulation/drug effects
- Gene Expression Regulation/genetics
- Citric Acid Cycle/drug effects
- Citric Acid Cycle/genetics
- Epilepsies, Myoclonic/diet therapy
- Epilepsies, Myoclonic/genetics
- Epilepsies, Myoclonic/physiopathology*
- 4-Aminopyridine/pharmacology
- Diet, Ketogenic/methods
- Oxygen Consumption/drug effects
- Oxygen Consumption/genetics*
- Mitochondria/drug effects
- Mitochondria/metabolism*
- Larva
- NAV1.1 Voltage-Gated Sodium Channel/genetics
- NAV1.1 Voltage-Gated Sodium Channel/metabolism
- PubMed
- 27066534 Full text @ eNeuro
Citation
Kumar, M.G., Rowley, S., Fulton, R., Dinday, M.T., Baraban, S.C., Patel, M. (2016) Altered Glycolysis and Mitochondrial Respiration in a Zebrafish Model of Dravet Syndrome. eNeuro. 3(2):e0008-16.
Abstract
Altered metabolism is an important feature of many epileptic syndromes but has not been reported in Dravet syndrome (DS), a catastrophic childhood epilepsy associated with mutations in a voltage-activated sodium channel, Nav1.1 (SCN1A). To address this, we developed novel methodology to assess real-time changes in bioenergetics in zebrafish larvae between 4 and 6 d postfertilization (dpf). Baseline and 4-aminopyridine (4-AP) stimulated glycolytic flux and mitochondrial respiration were simultaneously assessed using a Seahorse Biosciences extracellular flux analyzer. Scn1Lab mutant zebrafish showed a decrease in baseline glycolytic rate and oxygen consumption rate (OCR) compared to controls. A ketogenic diet formulation rescued mutant zebrafish metabolism to control levels. Increasing neuronal excitability with 4-AP resulted in an immediate increase in glycolytic rates in wild-type zebrafish, whereas mitochondrial OCR increased slightly and quickly recovered to baseline values. In contrast, scn1Lab mutant zebrafish showed a significantly slower and exaggerated increase of both glycolytic rates and OCR after 4-AP. The underlying mechanism of decreased baseline OCR in scn1Lab mutants was not because of altered mitochondrial DNA content or dysfunction of enzymes in the electron transport chain or tricarboxylic acid cycle. Examination of glucose metabolism using a PCR array identified five glycolytic genes that were downregulated in scn1Lab mutant zebrafish. Our findings in scn1Lab mutant zebrafish suggest that glucose and mitochondrial hypometabolism contribute to the pathophysiology of DS.
Genes / Markers
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Orthology
Engineered Foreign Genes
Mapping