Pharmacological enhancement of KCC2 gene expression exerts therapeutic effects on human Rett syndrome neurons and Mecp2 mutant mice

Sci Transl Med. 2019 Jul 31;11(503):eaau0164. doi: 10.1126/scitranslmed.aau0164.

Abstract

Rett syndrome (RTT) is a neurodevelopmental disorder caused by mutations in the methyl CpG binding protein 2 (MECP2) gene. There are currently no approved treatments for RTT. The expression of K+/Cl- cotransporter 2 (KCC2), a neuron-specific protein, has been found to be reduced in human RTT neurons and in RTT mouse models, suggesting that KCC2 might play a role in the pathophysiology of RTT. To develop neuron-based high-throughput screening (HTS) assays to identify chemical compounds that enhance the expression of the KCC2 gene, we report the generation of a robust high-throughput drug screening platform that allows for the rapid assessment of KCC2 gene expression in genome-edited human reporter neurons. From an unbiased screen of more than 900 small-molecule chemicals, we have identified a group of compounds that enhance KCC2 expression termed KCC2 expression-enhancing compounds (KEECs). The identified KEECs include U.S. Food and Drug Administration-approved drugs that are inhibitors of the fms-like tyrosine kinase 3 (FLT3) or glycogen synthase kinase 3β (GSK3β) pathways and activators of the sirtuin 1 (SIRT1) and transient receptor potential cation channel subfamily V member 1 (TRPV1) pathways. Treatment with hit compounds increased KCC2 expression in human wild-type (WT) and isogenic MECP2 mutant RTT neurons, and rescued electrophysiological and morphological abnormalities of RTT neurons. Injection of KEEC KW-2449 or piperine in Mecp2 mutant mice ameliorated disease-associated respiratory and locomotion phenotypes. The small-molecule compounds described in our study may have therapeutic effects not only in RTT but also in other neurological disorders involving dysregulation of KCC2.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anilides / pharmacology
  • Animals
  • Benzimidazoles / pharmacology
  • Clustered Regularly Interspaced Short Palindromic Repeats / genetics
  • Electroretinography
  • Enzyme Inhibitors / pharmacology
  • Female
  • Glycogen Synthase Kinase 3 beta / antagonists & inhibitors
  • Glycogen Synthase Kinase 3 beta / metabolism
  • Humans
  • Indazoles / pharmacology
  • K Cl- Cotransporters
  • Male
  • Methyl-CpG-Binding Protein 2 / genetics
  • Methyl-CpG-Binding Protein 2 / metabolism*
  • Mice
  • Neurons / cytology*
  • Neurons / drug effects
  • Piperazines / pharmacology
  • Piperidines / pharmacology
  • Pyridines / pharmacology
  • Pyrimidines / pharmacology
  • Pyrroles / pharmacology
  • Rett Syndrome / metabolism*
  • Sirtuin 1 / metabolism
  • Sunitinib / pharmacology
  • Symporters / genetics
  • Symporters / metabolism*
  • fms-Like Tyrosine Kinase 3 / antagonists & inhibitors
  • fms-Like Tyrosine Kinase 3 / metabolism

Substances

  • Anilides
  • Benzimidazoles
  • Enzyme Inhibitors
  • Indazoles
  • KW 2449
  • Mecp2 protein, mouse
  • Methyl-CpG-Binding Protein 2
  • Piperazines
  • Piperidines
  • Pyridines
  • Pyrimidines
  • Pyrroles
  • SLC12A5 protein, human
  • Symporters
  • TWS 119
  • cabozantinib
  • fms-Like Tyrosine Kinase 3
  • Glycogen Synthase Kinase 3 beta
  • Sirtuin 1
  • crenolanib
  • Sunitinib