PUBLICATION

Image-Based Measurement of H2O2 Reaction-Diffusion in Wounded Zebrafish Larvae.

Authors
Jelcic, M., Enyedi, B., Xavier, J.B., Niethammer, P.
ID
ZDB-PUB-170513-5
Date
2017
Source
Biophysical journal   112: 2011-2018 (Journal)
Registered Authors
Enyedi, Balázs, Niethammer, Philipp
Keywords
none
MeSH Terms
  • Animal Fins/growth & development
  • Animal Fins/injuries*
  • Animal Fins/metabolism
  • Animals
  • Animals, Genetically Modified
  • Antioxidants/metabolism
  • Diffusion
  • Hydrogen Peroxide/metabolism*
  • Image Processing, Computer-Assisted
  • Kinetics
  • Larva
  • Microscopy, Fluorescence*
  • Models, Animal
  • Molecular Imaging
  • Peroxiredoxins/metabolism
  • Tail/growth & development
  • Tail/injuries*
  • Tail/metabolism
  • Thioredoxins/metabolism
  • Zebrafish/growth & development
  • Zebrafish/injuries
  • Zebrafish/metabolism*
PubMed
28494970 Full text @ Biophys. J.
Abstract
Epithelial injury induces rapid recruitment of antimicrobial leukocytes to the wound site. In zebrafish larvae, activation of the epithelial NADPH oxidase Duox at the wound margin is required early during this response. Before injury, leukocytes are near the vascular region, that is, ∼100-300 μm away from the injury site. How Duox establishes long-range signaling to leukocytes is unclear. We conceived that extracellular hydrogen peroxide (H2O2) generated by Duox diffuses through the tissue to directly regulate chemotactic signaling in these cells. But before it can oxidize cellular proteins, H2O2 must get past the antioxidant barriers that protect the cellular proteome. To test whether, or on which length scales this occurs during physiological wound signaling, we developed a computational method based on reaction-diffusion principles that infers H2O2 degradation rates from intravital H2O2-biosensor imaging data. Our results indicate that at high tissue H2O2 levels the peroxiredoxin-thioredoxin antioxidant chain becomes overwhelmed, and H2O2 degradation stalls or ceases. Although the wound H2O2 gradient reaches deep into the tissue, it likely overcomes antioxidant barriers only within ∼30 μm of the wound margin. Thus, Duox-mediated long-range signaling may require other spatial relay mechanisms besides extracellular H2O2 diffusion.
Genes / Markers
Figures
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Antibodies
Orthology
Engineered Foreign Genes
Mapping