Fast neurogenesis from carotid body quiescent neuroblasts accelerates adaptation to hypoxia

EMBO Rep. 2018 Mar;19(3):e44598. doi: 10.15252/embr.201744598. Epub 2018 Jan 15.

Abstract

Unlike other neural peripheral organs, the adult carotid body (CB) has a remarkable structural plasticity, as it grows during acclimatization to hypoxia. The CB contains neural stem cells that can differentiate into oxygen-sensitive glomus cells. However, an extended view is that, unlike other catecholaminergic cells of the same lineage (sympathetic neurons or chromaffin cells), glomus cells can divide and thus contribute to CB hypertrophy. Here, we show that O2-sensitive mature glomus cells are post-mitotic. However, we describe an unexpected population of pre-differentiated, immature neuroblasts that express catecholaminergic markers and contain voltage-dependent ion channels, but are unresponsive to hypoxia. Neuroblasts are quiescent in normoxic conditions, but rapidly proliferate and differentiate into mature glomus cells during hypoxia. This unprecedented "fast neurogenesis" is stimulated by ATP and acetylcholine released from mature glomus cells. CB neuroblasts, which may have evolved to facilitate acclimatization to hypoxia, could contribute to the CB oversensitivity observed in highly prevalent human diseases.

Keywords: PNS niche; glomus cells; neural crest‐derived stem cells; neuroblast proliferation and maturation; oxygen sensing.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptation, Physiological / genetics*
  • Adenosine Triphosphate / metabolism
  • Carotid Body / growth & development*
  • Carotid Body / metabolism
  • Cell Differentiation / genetics*
  • Cell Proliferation / genetics
  • Humans
  • Hypoxia* / metabolism
  • Neural Stem Cells / cytology
  • Neural Stem Cells / metabolism
  • Neurogenesis / genetics*
  • Oxygen / metabolism

Substances

  • Adenosine Triphosphate
  • Oxygen