PACAP38 differentially effects genes and CRMP2 protein expression in ischemic core and penumbra regions of permanent middle cerebral artery occlusion model mice brain

Int J Mol Sci. 2014 Sep 23;15(9):17014-34. doi: 10.3390/ijms150917014.

Abstract

Pituitary adenylate-cyclase activating polypeptide (PACAP) has neuroprotective and axonal guidance functions, but the mechanisms behind such actions remain unclear. Previously we examined effects of PACAP (PACAP38, 1 pmol) injection intracerebroventrically in a mouse model of permanent middle cerebral artery occlusion (PMCAO) along with control saline (0.9% NaCl) injection. Transcriptomic and proteomic approaches using ischemic (ipsilateral) brain hemisphere revealed differentially regulated genes and proteins by PACAP38 at 6 and 24 h post-treatment. However, as the ischemic hemisphere consisted of infarct core, penumbra, and non-ischemic regions, specificity of expression and localization of these identified molecular factors remained incomplete. This led us to devise a new experimental strategy wherein, ischemic core and penumbra were carefully sampled and compared to the corresponding contralateral (healthy) core and penumbra regions at 6 and 24 h post PACAP38 or saline injections. Both reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting were used to examine targeted gene expressions and the collapsin response mediator protein 2 (CRMP2) protein profiles, respectively. Clear differences in expression of genes and CRMP2 protein abundance and degradation product/short isoform was observed between ischemic core and penumbra and also compared to the contralateral healthy tissues after PACAP38 or saline treatment. Results indicate the importance of region-specific analyses to further identify, localize and functionally analyse target molecular factors for clarifying the neuroprotective function of PACAP38.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cerebral Cortex / drug effects
  • Cerebral Cortex / metabolism
  • DNA, Complementary / genetics
  • Drug Evaluation, Preclinical
  • Gene Expression Profiling
  • Gene Expression Regulation / drug effects*
  • Infarction, Middle Cerebral Artery / drug therapy*
  • Infarction, Middle Cerebral Artery / genetics
  • Infarction, Middle Cerebral Artery / metabolism
  • Infarction, Middle Cerebral Artery / pathology
  • Intercellular Signaling Peptides and Proteins / biosynthesis*
  • Intercellular Signaling Peptides and Proteins / genetics
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Models, Animal
  • Nerve Tissue Proteins / biosynthesis*
  • Nerve Tissue Proteins / genetics
  • Neuroprotective Agents / administration & dosage
  • Neuroprotective Agents / pharmacology*
  • Pituitary Adenylate Cyclase-Activating Polypeptide / administration & dosage
  • Pituitary Adenylate Cyclase-Activating Polypeptide / pharmacology*
  • RNA, Messenger / biosynthesis
  • RNA, Messenger / genetics

Substances

  • DNA, Complementary
  • Intercellular Signaling Peptides and Proteins
  • Nerve Tissue Proteins
  • Neuroprotective Agents
  • Pituitary Adenylate Cyclase-Activating Polypeptide
  • RNA, Messenger
  • collapsin response mediator protein-2