ASK1-p38 MAPK/JNK signaling cascade mediates anandamide-induced PC12 cell death

J Neurochem. 2003 Apr;85(1):50-61. doi: 10.1046/j.1471-4159.2003.01663.x.

Abstract

Anandamide is a neuroimmunoregulatory molecule that triggers apoptosis in a number of cell types including PC12 cells. Here, we investigated the molecular mechanisms underlying anandamide-induced cell death in PC12 cells. Anandamide treatment resulted in the activation of p38 mitogen-activated protein kinase (MAPK), c-Jun N-terminal kinase (JNK), and p44/42 MAPK in apoptosing cells. A selective p38 MAPK inhibitor, SB203580, or dn-JNK, JNK1(A-F) or SAPKbeta(K-R), blocked anandamide-induced cell death, whereas a specific inhibitor of MEK-1/2, U0126, had no effect, indicating that activation of p38 MAPK and JNK is critical in anandamide-induced cell death. An important role for apoptosis signal-regulating kinase 1 (ASK1) in this event was also demonstrated by the inhibition of p38 MAPK/JNK activation and death in cells overexpressing dn-ASK1, ASK1 (K709M). Conversely, the constitutively active ASK1, ASK1DeltaN, caused prolonged p38 MAPK/JNK activation and increased cell death. These indicate that ASK1 mediates anandamide-induced cell death via p38 MAPK and JNK activation. Here, we also found that activation of p38 MAPK/JNK is accompanied by cytochrome c release from the mitochondria and caspase activation (which can be inhibited by SB203580), suggesting that anandamide triggers a mitochondrial dependent apoptotic pathway. The caspase inhibitor, zVAD, and the mitochondrial pore opening inhibitor, cyclosporine A, blocked anandamide-induced cell death but not p38 MAPK/JNK activation, suggesting that activation of these kinases may occur upstream of mitochondrial associated events.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Apoptosis / drug effects
  • Apoptosis / physiology
  • Arachidonic Acids / pharmacology*
  • Dose-Response Relationship, Drug
  • Endocannabinoids
  • Enzyme Activation / drug effects
  • Enzyme Inhibitors / pharmacology
  • JNK Mitogen-Activated Protein Kinases
  • MAP Kinase Kinase Kinase 5
  • MAP Kinase Kinase Kinases / genetics
  • MAP Kinase Kinase Kinases / metabolism*
  • Mitochondria / metabolism
  • Mitogen-Activated Protein Kinases / antagonists & inhibitors
  • Mitogen-Activated Protein Kinases / genetics
  • Mitogen-Activated Protein Kinases / metabolism*
  • PC12 Cells
  • Pheochromocytoma / drug therapy*
  • Pheochromocytoma / metabolism
  • Polyunsaturated Alkamides
  • Proto-Oncogene Proteins c-bcl-2 / biosynthesis
  • Proto-Oncogene Proteins c-bcl-2 / genetics
  • Proto-Oncogene Proteins c-bcl-2 / pharmacology
  • Rats
  • Receptors, Cannabinoid
  • Receptors, Drug / antagonists & inhibitors
  • Receptors, Drug / metabolism
  • Signal Transduction / drug effects
  • Signal Transduction / physiology*
  • Transfection
  • p38 Mitogen-Activated Protein Kinases

Substances

  • Arachidonic Acids
  • Endocannabinoids
  • Enzyme Inhibitors
  • Polyunsaturated Alkamides
  • Proto-Oncogene Proteins c-bcl-2
  • Receptors, Cannabinoid
  • Receptors, Drug
  • JNK Mitogen-Activated Protein Kinases
  • Mitogen-Activated Protein Kinases
  • p38 Mitogen-Activated Protein Kinases
  • MAP Kinase Kinase Kinase 5
  • MAP Kinase Kinase Kinases
  • anandamide