A small-molecule TrkB ligand restores hippocampal synaptic plasticity and object location memory in Rett syndrome mice

Academic Article

Abstract

  • © 2017. Published by The Company of Biologists Ltd | Disease Models & Mechanisms. Rett syndrome (RTT) is a neurodevelopmental disorder caused by mutations in methyl-CpG-binding protein-2 (MECP2), a transcriptional regulator of many genes, including brain-derived neurotrophic factor (BDNF). BDNF levels are reduced in RTT autopsy brains and in multiple brain areas of Mecp2-deficient mice. Furthermore, experimental interventions that increase BDNF levels improve RTT-like phenotypes in Mecp2 mutant mice. Here, we characterized the actions of a smallmolecule ligand of the BDNF receptor TrkB in hippocampal function in Mecp2 mutant mice. Systemic treatment of female Mecp2 heterozygous (HET) mice with LM22A-4 for 4 weeks improved hippocampaldependent object location memory and restored hippocampal longterm potentiation (LTP). Mechanistically, LM22A-4 acts to dampen hyperactive hippocampal network activity, reduce the frequency and amplitude of miniature excitatory postsynaptic currents (mEPSCs), and reduce the frequency of spontaneous tetrodotoxin-resistant Ca2+ signals in Mecp2 mutant hippocampal neurons, making them comparable to those features observed in wild-type neurons. Together, these observations indicate that LM22A-4 is a promising therapeutic candidate for the treatment of hippocampal dysfunction in RTT.
  • Digital Object Identifier (doi)

    Author List

  • Li W; Bellot-Saez A; Phillips ML; Yang T; Longo FM; Pozzo-Miller L
  • Start Page

  • 837
  • End Page

  • 845
  • Volume

  • 10
  • Issue

  • 7