HB-EGF activates EGFR to induce reactive neural stem cells in the mouse hippocampus after seizures

Life Sci Alliance. 2024 Jul 8;7(9):e202201840. doi: 10.26508/lsa.202201840. Print 2024 Sep.

Abstract

Hippocampal seizures mimicking mesial temporal lobe epilepsy cause a profound disruption of the adult neurogenic niche in mice. Seizures provoke neural stem cells to switch to a reactive phenotype (reactive neural stem cells, React-NSCs) characterized by multibranched hypertrophic morphology, massive activation to enter mitosis, symmetric division, and final differentiation into reactive astrocytes. As a result, neurogenesis is chronically impaired. Here, using a mouse model of mesial temporal lobe epilepsy, we show that the epidermal growth factor receptor (EGFR) signaling pathway is key for the induction of React-NSCs and that its inhibition exerts a beneficial effect on the neurogenic niche. We show that during the initial days after the induction of seizures by a single intrahippocampal injection of kainic acid, a strong release of zinc and heparin-binding epidermal growth factor, both activators of the EGFR signaling pathway in neural stem cells, is produced. Administration of the EGFR inhibitor gefitinib, a chemotherapeutic in clinical phase IV, prevents the induction of React-NSCs and preserves neurogenesis.

MeSH terms

  • Animals
  • Cell Differentiation / drug effects
  • Disease Models, Animal
  • Epilepsy, Temporal Lobe / metabolism
  • ErbB Receptors* / metabolism
  • Gefitinib / pharmacology
  • Heparin-binding EGF-like Growth Factor* / metabolism
  • Hippocampus* / metabolism
  • Kainic Acid / pharmacology
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Neural Stem Cells* / drug effects
  • Neural Stem Cells* / metabolism
  • Neurogenesis* / drug effects
  • Seizures* / metabolism
  • Signal Transduction* / drug effects

Substances

  • ErbB Receptors
  • Heparin-binding EGF-like Growth Factor
  • EGFR protein, mouse
  • Gefitinib
  • Kainic Acid
  • Hbegf protein, mouse