Developmental Alterations in Huntington's Disease Neural Cells and Pharmacological Rescue in Cells and Mice

Nat Neurosci. 2017 May;20(5):648-660. doi: 10.1038/nn.4532. Epub 2017 Mar 20.

Abstract

Neural cultures derived from Huntington's disease (HD) patient-derived induced pluripotent stem cells were used for 'omics' analyses to identify mechanisms underlying neurodegeneration. RNA-seq analysis identified genes in glutamate and GABA signaling, axonal guidance and calcium influx whose expression was decreased in HD cultures. One-third of gene changes were in pathways regulating neuronal development and maturation. When mapped to stages of mouse striatal development, the profiles aligned with earlier embryonic stages of neuronal differentiation. We observed a strong correlation between HD-related histone marks, gene expression and unique peak profiles associated with dysregulated genes, suggesting a coordinated epigenetic program. Treatment with isoxazole-9, which targets key dysregulated pathways, led to amelioration of expanded polyglutamine repeat-associated phenotypes in neural cells and of cognitive impairment and synaptic pathology in HD model R6/2 mice. These data suggest that mutant huntingtin impairs neurodevelopmental pathways that could disrupt synaptic homeostasis and increase vulnerability to the pathologic consequence of expanded polyglutamine repeats over time.

MeSH terms

  • Animals
  • Basic Helix-Loop-Helix Transcription Factors / biosynthesis
  • Cells, Cultured
  • Cognitive Dysfunction / drug therapy
  • Corpus Striatum / growth & development
  • Corpus Striatum / metabolism
  • Epigenomics
  • Gene Expression / drug effects
  • Gene Expression / physiology
  • Gene Expression Profiling
  • Gene Knockdown Techniques
  • Histones / metabolism
  • Humans
  • Huntingtin Protein / genetics
  • Huntington Disease / metabolism*
  • Induced Pluripotent Stem Cells / physiology
  • Isoxazoles / pharmacology
  • Isoxazoles / therapeutic use
  • Mice
  • Mice, Transgenic
  • Nerve Tissue Proteins / biosynthesis
  • Neurogenesis / physiology*
  • Neurons / metabolism*
  • Neurons / physiology*
  • Peptides / metabolism
  • Signal Transduction / drug effects
  • Thiophenes / pharmacology
  • Thiophenes / therapeutic use

Substances

  • Basic Helix-Loop-Helix Transcription Factors
  • HTT protein, human
  • Histones
  • Huntingtin Protein
  • Isoxazoles
  • N-cyclopropyl-5-(thiophen-2-yl)isoxazole-3-carboxamide
  • NEUROD1 protein, human
  • Nerve Tissue Proteins
  • Peptides
  • Thiophenes
  • polyglutamine