title: Morphology and intrinsic excitability of regenerating sensory and motor neurons grown on a line micropattern.
abstract: Axonal regeneration is one of the greatest challenges in severe injuries of peripheral nerve. To provide the bridge needed for regeneration, biological or synthetic tubular nerve constructs with aligned architecture have been developed. A key point for improving axonal regeneration is assessing the effects of substrate geometry on neuronal behavior. In the present study, we used an extracellular matrix-micropatterned substrate comprising 3 µm wide lines aimed to physically mimic the in vivo longitudinal axonal growth of mice peripheral sensory and motor neurons. Adult sensory neurons or embryonic motoneurons were seeded and processed for morphological and electrical activity analyses after two days in vitro. We show that micropattern-guided sensory neurons grow one or two axons without secondary branching. Motoneurons polarity was kept on micropattern with a long axon and small dendrites. The micro-patterned substrate maintains the growth promoting effects of conditioning injury and demonstrates, for the first time, that neurite initiation and extension could be differentially regulated by conditioning injury among DRG sensory neuron subpopulations. The micro-patterned substrate impacts the excitability of sensory neurons and promotes the apparition of firing action potentials characteristic for a subclass of mechanosensitive neurons. The line pattern is quite relevant for assessing the regenerative and developmental growth of sensory and motoneurons and offers a unique model for the analysis of the impact of geometry on the expression and the activity of mechanosensitive channels in DRG sensory neurons.
authors.affiliation: Université Montpellier 2, Laboratoire Charles Coulomb UMR 5221, Montpellier, France; CNRS, Laboratoire Charles Coulomb UMR 5221, Montpellier, France.
authors.forename: Ouafa
authors.initials: O
authors.lastname: Benzina
authors.affiliation: Université Montpellier 2, Laboratoire Charles Coulomb UMR 5221, Montpellier, France; CNRS, Laboratoire Charles Coulomb UMR 5221, Montpellier, France.
authors.forename: Thierry
authors.initials: T
authors.lastname: Cloitre
authors.affiliation: Université Montpellier 2, Laboratoire Charles Coulomb UMR 5221, Montpellier, France; CNRS, Laboratoire Charles Coulomb UMR 5221, Montpellier, France.
authors.forename: Marta
authors.initials: M
authors.lastname: Martin
authors.affiliation: Institut National de la Santé et de la Recherche Médicale, Inserm UMR1051, the neuroscience institute of Montpellier, Saint Eloi hospital, Montpellier, France; Université Montpellier 1, 2, Montpellier, France.
authors.forename: Cédric
authors.initials: C
authors.lastname: Raoul
authors.affiliation: Université Montpellier 2, Laboratoire Charles Coulomb UMR 5221, Montpellier, France; CNRS, Laboratoire Charles Coulomb UMR 5221, Montpellier, France.
authors.forename: Csilla
authors.initials: C
authors.lastname: Gergely
authors.affiliation: Institut National de la Santé et de la Recherche Médicale, Inserm UMR1051, the neuroscience institute of Montpellier, Saint Eloi hospital, Montpellier, France; Université Montpellier 1, 2, Montpellier, France.
authors.forename: Frédérique
authors.initials: F
authors.lastname: Scamps
mesh_terms: D000818:Animals; D001369:Axons / Q000378:metabolism; D002478:Cells, Cultured; D003712:Dendrites / Q000378:metabolism; D005727:Ganglia, Spinal / Q000166:cytology / Q000502:physiology*; D051379:Mice; D008822:Mice, Transgenic; D009046:Motor Neurons / Q000166:cytology / Q000378:metabolism*; D009416:Nerve Regeneration / Q000502:physiology*; D010525:Peripheral Nerves / Q000166:cytology / Q000502:physiology*; D011984:Sensory Receptor Cells / Q000166:cytology / Q000378:metabolism