Fractalkine reduces N-methyl-d-aspartate-induced calcium flux and apoptosis in human neurons through extracellular signal-regulated kinase activation

Eur J Neurosci. 2004 Dec;20(12):3222-32. doi: 10.1111/j.1460-9568.2004.03800.x.

Abstract

Our purpose was to investigate in human neurons the neuroprotective pathways induced by Fractalkine (FKN) against glutamate receptor-induced excitotoxicity. CX(3)CR1 and FKN are expressed constitutively in the tested human embryonic primary neurons and SK-N-SH, a human neuroblastoma cell line. Microfluorometry assay demonstrated that CX(3)CR1 was functional in 44% of primary neurons and in 70% of SK-N-SH. Fractalkine induced ERK1/2 phosphorylation within 1 min and Akt phosphorylation after 10 min, and both phosphorylation decreased after 20 min. No p38 and SAPK/JNK activation was observed after FKN treatment. Application of FKN triggered a 53% reduction of the NMDA-induced neuronal calcium influx, which was insensitive to pertussis toxin and LY294002 an inhibitor of Akt pathway, but abolished by PD98059, an ERK1/2 pathway inhibitor. Moreover, FKN significantly reduced neuronal NMDA-induced apoptosis, which was pertussis toxin insensitive and abolished in presence of PD98059 and LY294002. In conclusion, FKN protected human neurons from NMDA-mediated excitotoxicity in at least two ways with different kinetics: (i) an early ERK1/2 activation which reduced NMDA-mediated calcium flux; and (ii), a late Akt activation associated with the previously induced ERK1/2 activation.

Publication types

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

MeSH terms

  • Apoptosis / drug effects
  • Apoptosis / physiology*
  • Calcium / metabolism*
  • Cell Line, Tumor
  • Cells, Cultured
  • Chemokine CX3CL1
  • Chemokines, CX3C / biosynthesis*
  • Chemokines, CX3C / genetics
  • Chemokines, CX3C / pharmacology
  • Enzyme Activation / drug effects
  • Enzyme Activation / physiology
  • Extracellular Signal-Regulated MAP Kinases / metabolism*
  • Humans
  • Membrane Proteins / biosynthesis*
  • Membrane Proteins / genetics
  • Membrane Proteins / pharmacology
  • N-Methylaspartate / pharmacology*
  • Neurons / drug effects
  • Neurons / enzymology

Substances

  • CX3CL1 protein, human
  • Chemokine CX3CL1
  • Chemokines, CX3C
  • Membrane Proteins
  • N-Methylaspartate
  • Extracellular Signal-Regulated MAP Kinases
  • Calcium