Recombinant Slit2 attenuates neuronal apoptosis via the Robo1-srGAP1 pathway in a rat model of neonatal HIE

Neuropharmacology. 2019 Nov 1:158:107727. doi: 10.1016/j.neuropharm.2019.107727. Epub 2019 Jul 26.

Abstract

Apoptosis following hypoxic-ischemic injury to the brain plays a major role in neuronal cell death. The neonatal brain is more susceptible to injury as the cortical neurons are immature and there are lower levels of antioxidants. Slit2, an extracellular matrix protein, has been shown to be neuroprotective in various models of neurological diseases. However, there is no information about the role of Slit2 in neonatal hypoxia-ischemia. In this study, we evaluated the effect of Slit2 and its receptor Robo1 in a rat model with neonatal HIE. 10-day old rat pups were used to create the neonatal HIE model. The right common carotid artery was ligated followed by 2.5 h of hypoxia. Recombinant Slit2 was administered intranasally 1 h post HI, recombinant Robo1 was used as a decoy receptor and administered intranasally 1h before HI and srGAP1-siRNA was administered intracerebroventricularly 24 h before HI. Brain infarct area measurement, short-term and long-term neurological function tests, Western blot, immunofluorescence staining, Fluoro-Jade C staining, Nissl staining and TUNEL staining were the assessments done following drug administration. Recombinant Slit2 administration reduced neuronal apoptosis and neurological deficits after neonatal HIE which were reversed by co-administration of recombinant Robo1 and srGAP1-siRNA administration. Recombinant Slit2 showed improved outcomes possibly via the robo1-srGAP1 pathway which mediated the inhibition of RhoA. In this study, the results suggest that Slit2 may help in attenuation of apoptosis and could be a therapeutic agent for treatment of neonatal hypoxic ischemic encephalopathy.

Keywords: Apoptosis; HI; RhoA; Robo1; Slit2; srGap1.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Administration, Intranasal
  • Animals
  • Animals, Newborn
  • Apoptosis / drug effects*
  • GTPase-Activating Proteins / drug effects*
  • GTPase-Activating Proteins / metabolism
  • Hypoxia-Ischemia, Brain / metabolism
  • Hypoxia-Ischemia, Brain / physiopathology*
  • In Situ Nick-End Labeling
  • Injections, Intraventricular
  • Intercellular Signaling Peptides and Proteins / pharmacology*
  • Nerve Tissue Proteins / drug effects*
  • Nerve Tissue Proteins / metabolism
  • Nerve Tissue Proteins / pharmacology*
  • Neurons / drug effects*
  • RNA, Small Interfering
  • Rats
  • Receptors, Immunologic / drug effects*
  • Receptors, Immunologic / metabolism
  • Recombinant Proteins
  • Roundabout Proteins
  • Signal Transduction
  • rho GTP-Binding Proteins / drug effects
  • rho GTP-Binding Proteins / metabolism

Substances

  • GTPase-Activating Proteins
  • Intercellular Signaling Peptides and Proteins
  • Nerve Tissue Proteins
  • RNA, Small Interfering
  • Receptors, Immunologic
  • Recombinant Proteins
  • srGAP1 protein, rat
  • RhoA protein, rat
  • rho GTP-Binding Proteins
  • Slit homolog 2 protein