Perinatal asphyxia leads to PARP-1 overactivity, p65 translocation, IL-1β and TNF-α overexpression, and apoptotic-like cell death in mesencephalon of neonatal rats: prevention by systemic neonatal nicotinamide administration

Neurotox Res. 2015 May;27(4):453-65. doi: 10.1007/s12640-015-9517-0. Epub 2015 Feb 10.

Abstract

Perinatal asphyxia (PA) is a leading cause of neuronal damage in newborns, resulting in long-term neurological and cognitive deficits, in part due to impairment of mesostriatal and mesolimbic neurocircuitries. The insult can be as severe as to menace the integrity of the genome, triggering the overactivation of sentinel proteins, including poly (ADP-ribose) polymerase-1 (PARP-1). PARP-1 overactivation implies increased energy demands, worsening the metabolic failure and depleting further NAD(+) availability. Using a global PA rat model, we report here evidence that hypoxia increases PARP-1 activity, triggering a signalling cascade leading to nuclear translocation of the NF-κB subunit p65, modulating the expression of IL-1β and TNF-α, pro-inflammatory molecules, increasing apoptotic-like cell death in mesencephalon of neonate rats, monitored with Western blots, qPCR, TUNEL and ELISA. PARP-1 activity increased immediately after PA, reaching a maximum 1-8 h after the insult, while activation of the NF-κB signalling pathway was observed 8 h after the insult, with a >twofold increase of p65 nuclear translocation. IL-1β and TNF-α mRNA levels were increased 24 h after the insult, together with a >twofold increase in apoptotic-like cell death. A single dose of the PARP-1 inhibitor nicotinamide (0.8 mmol/kg, i.p.), 1 h post delivery, prevented the effect of PA on PARP-1 activity, p65 translocation, pro-inflammatory cytokine expression and apoptotic-like cell death. The present study demonstrates that PA leads to PARP-1 overactivation, increasing the expression of pro-inflammatory cytokines and cell death in mesencephalon, effects prevented by systemic neonatal nicotinamide administration, supporting the idea that PARP-1 inhibition represents a therapeutic target against the effects of PA.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Animals, Newborn
  • Apoptosis / drug effects
  • Asphyxia / enzymology
  • Asphyxia / metabolism*
  • Asphyxia Neonatorum / enzymology
  • Asphyxia Neonatorum / metabolism*
  • Humans
  • Inflammation / metabolism
  • Interleukin-1beta / metabolism
  • Mesencephalon / drug effects
  • Mesencephalon / enzymology
  • Mesencephalon / metabolism*
  • Neoplasm Proteins / metabolism
  • Niacinamide / administration & dosage*
  • Nucleocytoplasmic Transport Proteins / metabolism
  • Poly (ADP-Ribose) Polymerase-1
  • Poly(ADP-ribose) Polymerases / metabolism*
  • Rats
  • Rats, Wistar
  • Signal Transduction*
  • Tumor Necrosis Factor-alpha / metabolism

Substances

  • Interleukin-1beta
  • Neoplasm Proteins
  • Nucleocytoplasmic Transport Proteins
  • Tumor Necrosis Factor-alpha
  • p65 oncofetal mRNA transport protein, rat
  • Niacinamide
  • Parp1 protein, rat
  • Poly (ADP-Ribose) Polymerase-1
  • Poly(ADP-ribose) Polymerases