Related Experiment Video
Updated: Aug 8, 2026
Chromatin Immunoprecipitation from Dorsal Root Ganglia Tissue following Axonal Injury
Published on: July 20, 2011
Inhibitors of poly(ADP-ribose) polymerase modulate signal transduction pathways and secondary damage in experimental
Tiziana Genovese1, Emanuela Mazzon, Carmelo Muià
1Department of Clinical and Experimental Medicine and Pharmacology, School of Medicine, University of Messina, Torre Biologica, Policlinico Universitario Via C. Valeria, Gazzi, 98100 Messina, Italy.
Abstract:
Poly(ADP-ribose) polymerase (PARP), a nuclear enzyme activated by strand breaks in DNA, plays an important role in the tissue injury associated with stroke and neurotrauma. The aim of our study was to evaluate the therapeutic efficacy of in vivo inhibition of PARP in an experimental model of spinal cord trauma, which was induced by the application of vascular clips (force of 24g) to the dura via a four-level T5-T8 laminectomy. Spinal cord injury in mice resulted in severe trauma characterized by edema, neutrophil infiltration (measured as an increase in myeloperoxidase activity), and apoptosis (measured by terminal deoxynucleotidyltransferase-mediated UTP end labeling coloration). Infiltration of spinal cord tissue with neutrophils was associated with a marked increase in immunoreactivity for poly(ADP-ribose) (PAR), index of PARP activation, in the spinal cord tissue. These inflammatory events were associated with the activation of nuclear factor-kappaB (NF-kappaB) at 4 h after spinal cord damage. Treatment of the mice with the PARP inhibitors 3-aminobenzamide (3-AB) or 5-aminoisoquinolinone (5-AIQ) significantly reduced the degree of 1) spinal cord inflammation and tissue injury (histological score), 2) PAR formation, 3) neutrophil infiltration, and 4) apoptosis. Treatment with these PARP inhibitors also reduced DNA binding of NF-kappaB and inhibitory kappaB degradation. In a separate set of experiments, we have also demonstrated that PARP inhibitors significantly ameliorated the recovery of limb function (evaluated by motor recovery score). Taken together, our results clearly demonstrate that treatment with PARP inhibitors reduces the development of inflammation and tissue injury events associated with spinal cord trauma.
Insights
Inhibiting poly(ADP-ribose) polymerase (PARP) with drugs reduced inflammation, tissue damage, and apoptosis after spinal cord injury in mice. This therapeutic approach also improved motor function recovery.
Area of Science:
- Neuroscience
- Biochemistry
- Pharmacology
Background:
- Poly(ADP-ribose) polymerase (PARP) is a nuclear enzyme crucial in DNA repair and cellular responses to injury.
- PARP activation is implicated in the tissue damage following stroke and neurotrauma.
- Spinal cord trauma triggers inflammatory and apoptotic pathways, contributing to secondary injury.
Purpose of the Study:
- To investigate the therapeutic potential of inhibiting PARP in a mouse model of spinal cord trauma.
- To evaluate the effects of PARP inhibitors on inflammation, apoptosis, and functional recovery after spinal cord injury.
Main Methods:
- Spinal cord trauma was induced in mice using vascular clips.
- PARP activation was assessed by measuring poly(ADP-ribose) (PAR) formation.
- Inflammation was quantified by neutrophil infiltration (myeloperoxidase activity) and histological scoring.
- Apoptosis was measured using terminal deoxynucleotidyltransferase-mediated UTP end labeling.
- Nuclear factor-kappaB (NF-kappaB) activation was analyzed.
- Mice were treated with PARP inhibitors (3-aminobenzamide or 5-aminoisoquinolinone).
- Motor function recovery was evaluated using a motor recovery score.
Main Results:
- Spinal cord injury led to significant edema, neutrophil infiltration, apoptosis, and NF-kappaB activation.
- PARP activation (PAR formation) increased in injured spinal cord tissue.
- Treatment with PARP inhibitors markedly reduced spinal cord inflammation, tissue injury, PAR formation, neutrophil infiltration, and apoptosis.
- PARP inhibitors also decreased NF-kappaB activation and improved motor recovery.
- Histological scores and apoptosis levels were significantly lower in treated mice.
Conclusions:
- Inhibition of PARP is a promising therapeutic strategy for mitigating secondary injury after spinal cord trauma.
- PARP inhibitors effectively reduce inflammation, apoptosis, and tissue damage, leading to improved functional outcomes.
- Targeting PARP may offer a novel approach to treating neurotrauma and related conditions.
Related Concept Videos
01:19Interactions Between Signaling Pathways
Convergence and divergence, and cross-talk between signaling pathways
Two distinct signaling pathways can converge on a single functional unit, which may either be a single protein or a complex of proteins. The response is either functionally distinct or synergistic between the two pathways but different from the response...
01:22Amplifying Signals via Enzymatic Cascade
01:20The JAK-STAT Signaling Pathway
01:30Inhibitors of Viral Protein Synthesis
01:14Spinal Cord Injury ll: Pathophysiology
01:25Secondary Spinal Cord Injury llI: Pathophysiology