Spatiotemporal Dynamics of Sensory Neuron and Merkel-Cell Remodeling During Epidermal Homeostasis
May 2023
sensory neurons Merkel cells epidermal homeostasis sensory axon terminals epithelial regeneration hair growth axonal remodeling hyperbranched axons kylix endings in vivo imaging two-photon microscopy whole-mount immunohistochemistry skin homeostasis nerve endings hair regeneration axon remodeling imaging techniques
TLDR Sensory neuron and Merkel cell changes in the skin happen independently during normal skin maintenance.
The study "Spatiotemporal dynamics of sensory neuron and Merkel-cell remodeling are decoupled during epidermal homeostasis" investigates the remodeling of sensory neurons and Merkel cells in the skin's epithelial layer. The research found that sensory axon terminals are highly dynamic, with 89% of terminal branches undergoing remodeling, compared to 63% of Merkel cells. The study also discovered two distinct populations of Merkel cells with different lifetimes and that the plasticity of Merkel cells, but not axonal remodeling, is synchronized to the rapid epithelial regeneration that occurs during hair growth. The research suggests that Merkel cells stabilize axonal branches, suppress excessive branching, and promote maturation of terminal morphology. The absence of Merkel cells results in hyperbranched axons and a lack of specific nerve endings, known as kylix endings. The study involved imaging of 20 axons in four mice and used various methods including in vivo imaging, two-photon microscopy, and whole-mount immunohistochemistry.