Artemisinins Target GABA A Receptor Signaling and Impair α Cell Identity

Cell. 2017 Jan 12;168(1-2):86-100.e15. doi: 10.1016/j.cell.2016.11.010. Epub 2016 Dec 1.

Abstract

Type 1 diabetes is characterized by the destruction of pancreatic β cells, and generating new insulin-producing cells from other cell types is a major aim of regenerative medicine. One promising approach is transdifferentiation of developmentally related pancreatic cell types, including glucagon-producing α cells. In a genetic model, loss of the master regulatory transcription factor Arx is sufficient to induce the conversion of α cells to functional β-like cells. Here, we identify artemisinins as small molecules that functionally repress Arx by causing its translocation to the cytoplasm. We show that the protein gephyrin is the mammalian target of these antimalarial drugs and that the mechanism of action of these molecules depends on the enhancement of GABAA receptor signaling. Our results in zebrafish, rodents, and primary human pancreatic islets identify gephyrin as a druggable target for the regeneration of pancreatic β cell mass from α cells.

Keywords: ARX translocation; GABA-receptor signaling; artemisinins; chemical biology; diabetes; gephyrin; insulin secretion; pancreatic endocrine transdifferentiation; regenerative medicine; β cell.

MeSH terms

  • Animals
  • Artemether
  • Artemisinins / administration & dosage
  • Artemisinins / pharmacology*
  • Carrier Proteins / metabolism
  • Cell Transdifferentiation / drug effects
  • Cells, Cultured
  • Diabetes Mellitus / drug therapy
  • Diabetes Mellitus, Type 1 / drug therapy*
  • Diabetes Mellitus, Type 1 / pathology
  • Disease Models, Animal*
  • Gene Expression Profiling
  • Homeodomain Proteins / metabolism
  • Humans
  • Insulin / genetics
  • Insulin / metabolism
  • Islets of Langerhans / drug effects
  • Membrane Proteins / metabolism
  • Mice
  • Protein Stability / drug effects
  • Rats
  • Receptors, GABA-A / metabolism*
  • Signal Transduction*
  • Single-Cell Analysis
  • Transcription Factors / metabolism
  • Zebrafish
  • gamma-Aminobutyric Acid / metabolism

Substances

  • ARX protein, human
  • Artemisinins
  • Carrier Proteins
  • Homeodomain Proteins
  • Insulin
  • Membrane Proteins
  • Receptors, GABA-A
  • Transcription Factors
  • gephyrin
  • gamma-Aminobutyric Acid
  • Artemether