Modeling Environmentally-Induced Motor Neuron Degeneration in Zebrafish

Sci Rep. 2018 Mar 20;8(1):4890. doi: 10.1038/s41598-018-23018-w.

Abstract

Zebrafish have been used to investigate motor neuron degeneration, including as a model system to examine the pathogenesis of amyotrophic lateral sclerosis (ALS). The use of zebrafish for this purpose has some advantages over other in vivo model systems. In the current paper, we show that bisphenol A (BPA) exposure in zebrafish embryos results in motor neuron degeneration with affected motor function, reduced motor axon length and branching, reduced neuromuscular junction integrity, motor neuron cell death and the presence of activated microglia. In zebrafish, motor axon length is the conventional method for estimating motor neuron degeneration, yet this measurement has not been confirmed as a valid surrogate marker. We also show that reduced motor axon length as measured from the sagittal plane is correlated with increased motor neuron cell death. Our preliminary timeline studies suggest that axonopathy precedes motor cell death. This outcome may have implications for early phase treatments of motor neuron degeneration.

MeSH terms

  • Amyotrophic Lateral Sclerosis / metabolism
  • Animals
  • Axons / metabolism
  • Disease Models, Animal
  • Hazardous Substances / adverse effects
  • Motor Neuron Disease / pathology*
  • Motor Neurons / metabolism
  • Nerve Degeneration / pathology*
  • Nervous System Malformations / metabolism
  • Neuromuscular Junction / metabolism
  • Superoxide Dismutase / metabolism
  • Zebrafish / metabolism
  • Zebrafish Proteins / metabolism

Substances

  • Hazardous Substances
  • Zebrafish Proteins
  • Superoxide Dismutase