Nuclear poly(ADP-ribose) activity is a therapeutic target in amyotrophic lateral sclerosis

Acta Neuropathol Commun. 2018 Aug 29;6(1):84. doi: 10.1186/s40478-018-0586-1.


Amyotrophic lateral sclerosis (ALS) is a devastating and fatal motor neuron disease. Diagnosis typically occurs in the fifth decade of life and the disease progresses rapidly leading to death within ~ 2-5 years of symptomatic onset. There is no cure, and the few available treatments offer only a modest extension in patient survival. A protein central to ALS is the nuclear RNA/DNA-binding protein, TDP-43. In > 95% of ALS patients, TDP-43 is cleared from the nucleus and forms phosphorylated protein aggregates in the cytoplasm of affected neurons and glia. We recently defined that poly(ADP-ribose) (PAR) activity regulates TDP-43-associated toxicity. PAR is a posttranslational modification that is attached to target proteins by PAR polymerases (PARPs). PARP-1 and PARP-2 are the major enzymes that are active in the nucleus. Here, we uncovered that the motor neurons of the ALS spinal cord were associated with elevated nuclear PAR, suggesting elevated PARP activity. Veliparib, a small-molecule inhibitor of nuclear PARP-1/2, mitigated the formation of cytoplasmic TDP-43 aggregates in mammalian cells. In primary spinal-cord cultures from rat, Veliparib also inhibited TDP-43-associated neuronal death. These studies uncover that PAR activity is misregulated in the ALS spinal cord, and a small-molecular inhibitor of PARP-1/2 activity may have therapeutic potential in the treatment of ALS and related disorders associated with abnormal TDP-43 homeostasis.

Keywords: ABT-888/Veliparib; Motor neuron disease, primary neuron; PAR; PARylation; Parp; Poly(ADP-ribose); TDP-43.

Publication types

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

MeSH terms

  • Adult
  • Aged
  • Amyotrophic Lateral Sclerosis / genetics
  • Amyotrophic Lateral Sclerosis / pathology*
  • Animals
  • Ataxin-2 / genetics
  • Ataxin-2 / metabolism
  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism
  • Benzimidazoles / pharmacology
  • C9orf72 Protein / genetics
  • C9orf72 Protein / metabolism
  • COS Cells
  • Cell Nucleus / metabolism*
  • Cells, Cultured
  • Chlorocebus aethiops
  • Cohort Studies
  • DNA-Binding Proteins
  • Dose-Response Relationship, Drug
  • Female
  • Humans
  • Luminescent Proteins / genetics
  • Luminescent Proteins / metabolism
  • Male
  • Middle Aged
  • Motor Neurons / metabolism
  • Motor Neurons / ultrastructure*
  • Mutation / genetics
  • Poly Adenosine Diphosphate Ribose / metabolism*
  • Poly(ADP-ribose) Polymerase Inhibitors / pharmacology
  • Rats
  • Saponins / pharmacology
  • Spinal Cord / pathology
  • Transfection
  • Triterpenes / pharmacology


  • ATXN2 protein, human
  • Ataxin-2
  • Bacterial Proteins
  • Benzimidazoles
  • C9orf72 Protein
  • C9orf72 protein, human
  • DNA-Binding Proteins
  • Luminescent Proteins
  • Poly(ADP-ribose) Polymerase Inhibitors
  • Saponins
  • TARDBP protein, human
  • Triterpenes
  • sodium aescinate
  • yellow fluorescent protein, Bacteria
  • veliparib
  • Poly Adenosine Diphosphate Ribose