Modeling Motor Neuron Resilience in ALS Using Stem Cells

Ilary Allodi,Gillian Bonvicini,Ming Cao,Eva Hedlund,Andrea Fuchs,Ole Kiehn,Julio Aguila Benitez,Jik Nijssen,Christoph Schweingruber

doi:10.1016/j.stemcr.2019.04.009

Ilary Allodi, Gillian Bonvicini + Show 7 more

Open Access

https://doi.org/10.1016/j.stemcr.2019.04.009

Copy DOI

Abstract

SummaryOculomotor neurons, which regulate eye movement, are resilient to degeneration in the lethal motor neuron disease amyotrophic lateral sclerosis (ALS). It would be highly advantageous if motor neuron resilience could be modeled in vitro. Toward this goal, we generated a high proportion of oculomotor neurons from mouse embryonic stem cells through temporal overexpression of PHOX2A in neuronal progenitors. We demonstrate, using electrophysiology, immunocytochemistry, and RNA sequencing, that in vitro-generated neurons are bona fide oculomotor neurons based on their cellular properties and similarity to their in vivo counterpart in rodent and man. We also show that in vitro-generated oculomotor neurons display a robust activation of survival-promoting Akt signaling and are more resilient to the ALS-like toxicity of kainic acid than spinal motor neurons. Thus, we can generate bona fide oculomotor neurons in vitro that display a resilience similar to that seen in vivo.

Highlights

Amyotrophic lateral sclerosis (ALS) is characterized by a loss of motor neurons in cortex, brain stem, and spinal cord with subsequent spasticity, muscle atrophy, and paralysis
We can generate bona fide oculomotor neurons in vitro that display a resilience to ALS similar to that seen in vivo
Bona Fide Oculomotor Neurons Can Be Generated from mouse embryonic stem cells (mESCs) To characterize the specific identity of brain stem motor neurons generated in culture and compare their properties with those of spinal motor neurons, we generated neurons from mESCs

Summary

Introduction

Amyotrophic lateral sclerosis (ALS) is characterized by a loss of motor neurons in cortex, brain stem, and spinal cord with subsequent spasticity, muscle atrophy, and paralysis. Motor neurons innervating the extraocular muscles, including the oculomotor, trochlear, and abducens nuclei, are relatively resistant to degeneration in ALS (Comley et al, 2016; Gizzi et al, 1992; Nijssen et al, 2017; Nimchinsky et al, 2000) This resilience has been attributed to cell-intrinsic properties (Allodi et al, 2016; Brockington et al, 2013; Comley et al, 2015; Hedlund et al, 2010; Kaplan et al, 2014). It would be highly advantageous if differential motor neuron vulnerability could be modeled in vitro. It is not self-evident that in vitro-generated oculomotor neurons would be more resistant to degeneration in culture than spinal motor neurons, as multiple cell types contribute to motor neuron degeneration in ALS, including, for example, astrocytes (Yamanaka et al, 2008), microglia (Boillee et al, 2006), and oligodendrocytes (Kang et al, 2013), and may play a role in selective vulnerability

Results

Discussion

Conclusion