Inhibition of Na+/H+ Exchanger Isoform 1 Is Neuroprotective in Neonatal Hypoxic Ischemic Brain Injury

Cengiz P., KLEMAN N., ULUC K., Kendigelen P., HAGEMANN T., AKTURE E., ...More

ANTIOXIDANTS & REDOX SIGNALING, vol.14, no.10, pp.1803-1813, 2011 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 14 Issue: 10
  • Publication Date: 2011
  • Doi Number: 10.1089/ars.2010.3468
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.1803-1813
  • Istanbul University Affiliated: No


We investigated the role of Na+/H+ exchanger isoform 1 (NHE-1) in neonatal hypoxia/ischemia (HI). HI was induced by unilateral ligation of the left common carotid artery in postnatal day 9 (P9) mice, and subsequent exposure of animals to 8% O-2 for 55 min. A pre/posttreatment group received a selective and potent NHE-1 inhibitor HOE 642 (0.5 mg/kg, intraperitoneally) 5 min before HI, then at 24 and 48 h after HI. A posttreatment group received HOE 642 (0.5 mg/kg) at 10 min, 24 h, and 48 h after HI. Saline injections were used as vehicle controls. The vehicle-control brains at 72 h after HI exhibited neuronal degeneration in the ipsilateral hippocampus, striatum, and thalamus, as identified with Fluoro-Jade C positive staining and loss of microtubule-associated protein 2 (MAP2) expression. NHE-1 protein was upregulated in glial fibrillary acidic protein-positive reactive astrocytes. In HOE 642-treated brains, the morphologic hippocampal structures were better preserved and displayed less neurodegeneration and a higher level of MAP2 expression. Motor-learning deficit was detected at 4 weeks of age after HI in the vehicle control group. Inhibition of NHE-1 in P9 mice not only reduced neurodegeneration during the acute stage of HI but also improved the striatum-dependent motor learning and spatial learning at 8 weeks of age after HI. These findings suggest that NHE-1-mediated disruption of ionic homeostasis contributes to striatal and CA1 pyramidal neuronal injury after neonatal HI. Antioxid. Redox Signal. 14, 1803-1813.