PUBLICATION

Corticotropin-releasing factor protects against ammonia neurotoxicity in isolated larval zebrafish brains

Authors
Williams, T.A., Bernier, N.J.
ID
ZDB-PUB-200129-8
Date
2020
Source
The Journal of experimental biology   223(Pt 4): (Journal)
Registered Authors
Keywords
CRF, Cell death, Cytoprotection, Hyperammonemia, Neural markers
MeSH Terms
  • Ammonia/toxicity*
  • Animals
  • Brain/metabolism
  • Cell Death/drug effects
  • Corticotropin-Releasing Hormone/pharmacology*
  • Dizocilpine Maleate/pharmacology
  • Gene Expression Regulation, Developmental
  • Larva/drug effects
  • Larva/metabolism
  • Pyrimidines/pharmacology
  • Pyrroles/pharmacology
  • Receptors, Corticotropin-Releasing Hormone/drug effects
  • Receptors, N-Methyl-D-Aspartate/drug effects
  • Zebrafish/embryology*
  • Zebrafish/genetics
  • Zebrafish/metabolism
PubMed
31988165 Full text @ J. Exp. Biol.
Abstract
The physiological roles of corticotropin-releasing factor (CRF) have recently been extended to cytoprotection. Here, to determine whether CRF is neuroprotective in fish, the effects of CRF against high environmental ammonia (HEA)-mediated neurogenic impairment and cell death were investigated in zebrafish. In vivo, exposure of 1 day post-fertilization (dpf) embryos to HEA only reduced the expression of the determined neuron marker, neurod1 In contrast, in 5 dpf larvae, HEA increased the expression of nes and sox2, neural progenitor cell markers, and reduced the expression of neurog1, gfap and mbpa, proneuronal cell, radial glia and oligodendrocyte markers, respectively, and neurod1 The N-methyl-D-aspartate (NMDA) receptor inhibitor MK801 rescued the HEA-induced reduction in neurod1 in 5 dpf larvae but did not affect the HEA-induced transcriptional changes in other neural cell types, suggesting that hyperactivation of NMDA receptors specifically contributes to the deleterious effects of HEA in determined neurons. As observed in vivo, HEA exposure elicited marked changes in the expression of cell-type specific markers in isolated 5 dpf larval brains. The addition of CRF reversed the in vitro effects of HEA on neurod1 expression and prevented an HEA-induced increase in cell death. Finally, the protective effects of CRF against HEA-mediated neurogenic impairment and cell death were prevented by the CRF type 1 receptor selective antagonist, antalarmin. Together, these results provide novel evidence that HEA has developmental time- and cell type-specific neurotoxic effects, that NMDA receptor hyperactivation contributes to HEA-mediated impairment of determined neurons, and that CRF has neuroprotective properties in the larval zebrafish brain.
Genes / Markers
Figures
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Antibodies
Orthology
Engineered Foreign Genes
Mapping