Hexokinase I N-terminal based peptide prevents the VDAC1-SOD1 G93A interaction and re-establishes ALS cell viability

Sci Rep. 2016 Oct 10:6:34802. doi: 10.1038/srep34802.

Abstract

Superoxide Dismutase 1 mutants associate with 20-25% of familial Amyotrophic Lateral Sclerosis (ALS) cases, producing toxic aggregates on mitochondria, notably in spinal cord. The Voltage Dependent Anion Channel isoform 1 (VDAC1) in the outer mitochondrial membrane is a docking site for SOD1 G93A mutant in ALS mice and the physiological receptor of Hexokinase I (HK1), which is poorly expressed in mouse spinal cord. Our results demonstrate that HK1 competes with SOD1 G93A for binding VDAC1, suggesting that in ALS spinal cord the available HK1-binding sites could be used by SOD1 mutants for docking mitochondria, producing thus organelle dysfunction. We tested this model by studying the action of a HK1-N-terminal based peptide (NHK1). This NHK1 peptide specifically interacts with VDAC1, inhibits the SOD1 G93A binding to mitochondria and restores the viability of ALS model NSC34 cells. Altogether, our results suggest that NHK1 peptide could be developed as a therapeutic tool in ALS, predicting an effective role also in other proteinopathies.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amyotrophic Lateral Sclerosis / metabolism
  • Amyotrophic Lateral Sclerosis / pathology*
  • Animals
  • Binding Sites
  • Binding, Competitive
  • Cell Line
  • Cell Survival / drug effects
  • Hexokinase / chemistry
  • Hexokinase / metabolism*
  • Humans
  • Membrane Potential, Mitochondrial
  • Mice
  • Mitochondria / drug effects
  • Mitochondria / metabolism
  • Mitochondria / pathology
  • Molecular Targeted Therapy
  • Motor Neurons / cytology
  • Motor Neurons / drug effects
  • Mutation
  • Peptide Fragments / pharmacology*
  • Superoxide Dismutase-1 / genetics
  • Superoxide Dismutase-1 / metabolism*
  • Voltage-Dependent Anion Channel 1 / genetics
  • Voltage-Dependent Anion Channel 1 / metabolism*

Substances

  • Peptide Fragments
  • SOD1 protein, human
  • VDAC1 protein, human
  • Superoxide Dismutase-1
  • Voltage-Dependent Anion Channel 1
  • HK1 protein, human
  • Hexokinase