Interleukin-1beta enhances nucleotide-induced and alpha-secretase-dependent amyloid precursor protein processing in rat primary cortical neurons via up-regulation of the P2Y(2) receptor

J Neurochem. 2009 Jun;109(5):1300-10. doi: 10.1111/j.1471-4159.2009.06048.x. Epub 2009 Mar 20.

Abstract

The heterologous expression and activation of the human P2Y(2) nucleotide receptor (P2Y(2)R) in human 1321N1 astrocytoma cells stimulates alpha-secretase-dependent cleavage of the amyloid precursor protein (APP), causing extracellular release of the non-amyloidogenic protein secreted amyloid precursor protein (sAPPalpha). To determine whether a similar response occurs in a neuronal cell, we analyzed whether P2Y(2)R-mediated production of sAPPalpha occurs in rat primary cortical neurons (rPCNs). In rPCNs, P2Y(2)R mRNA and receptor activity were virtually absent in quiescent cells, whereas overnight treatment with the pro-inflammatory cytokine interleukin-1beta (IL-1beta) up-regulated both P2Y(2)R mRNA expression and receptor activity by four-fold. The up-regulation of the P2Y(2)R was abrogated by pre-incubation with Bay 11-7085, an IkappaB-alpha phosphorylation inhibitor, which suggests that P2Y(2)R mRNA transcript levels are regulated through nuclear factor-kappa-B (NFkappaB) signaling. Furthermore, the P2Y(2)R agonist Uridine-5'-triphosphate (UTP) enhanced the release of sAPPalpha in rPCNs treated with IL-1beta or transfected with P2Y(2)R cDNA. UTP-induced release of sAPPalpha from rPCNs was completely inhibited by pre-treatment of the cells with the metalloproteinase inhibitor TACE inhibitor (TAPI-2) or the phosphatidylinositol 3-kinase (PI3K) inhibitor LY294002, and was partially inhibited by the MAPK/extracellular signal-regulated kinase inhibitor U0126 and the protein kinase C inhibitor GF109203. These data suggest that P2Y(2)R-mediated release of sAPPalpha from cortical neurons is directly dependent on a disintegrin and metalloproteinase (ADAM) 10/17 and PI3K activity, whereas extracellular signal-regulated kinase 1/2 and PI3K activity may indirectly regulate APP processing. These results demonstrate that elevated levels of pro-inflammatory cytokines associated with neurodegenerative diseases, such as IL-1beta, can enhance non-amyloidogenic APP processing through up-regulation of the P2Y(2)R in neurons.

Publication types

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

MeSH terms

  • Amyloid Precursor Protein Secretases / metabolism
  • Amyloid beta-Protein Precursor / metabolism*
  • Analysis of Variance
  • Animals
  • Cerebral Cortex / cytology*
  • Dose-Response Relationship, Drug
  • Drug Interactions
  • Embryo, Mammalian
  • Enzyme Inhibitors / pharmacology
  • Humans
  • Interleukin-1beta / pharmacology*
  • Neurons / drug effects*
  • Neurons / metabolism*
  • Nucleotides / pharmacology
  • RNA, Messenger / metabolism
  • Rats
  • Rats, Sprague-Dawley
  • Receptors, Purinergic P2 / genetics
  • Receptors, Purinergic P2 / metabolism*
  • Receptors, Purinergic P2Y2
  • Signal Transduction / drug effects
  • Tetradecanoylphorbol Acetate / analogs & derivatives
  • Tetradecanoylphorbol Acetate / pharmacology
  • Transfection / methods
  • Up-Regulation / drug effects*
  • Uridine Triphosphate / pharmacology

Substances

  • Amyloid beta-Protein Precursor
  • Enzyme Inhibitors
  • Interleukin-1beta
  • Nucleotides
  • P2RY2 protein, human
  • P2ry2 protein, rat
  • RNA, Messenger
  • Receptors, Purinergic P2
  • Receptors, Purinergic P2Y2
  • 4-O-methyl-12-O-tetradecanoylphorbol 13-acetate
  • Amyloid Precursor Protein Secretases
  • Tetradecanoylphorbol Acetate
  • Uridine Triphosphate