Arachidonic acid-induced apoptosis of human neuroblastoma SK-N-SH cells is mediated through mitochondrial alteration elicited by ROS and Ca(2+)-evoked activation of p38alpha MAPK and JNK1

Toxicology. 2009 Aug 21;262(3):199-206. doi: 10.1016/j.tox.2009.06.009. Epub 2009 Jun 21.

Abstract

Arachidonic acid (AA)-induced apoptosis of human neuroblastoma SK-N-SH cells was characteristic of elevation of intracellular Ca(2+) concentration ([Ca(2+)]i), ROS generation, activation of 38 MAPK and JNK and loss of mitochondrial membrane potential (DeltaPsim). Subsequent modulation of Bcl-2 family members and cytochrome c release accompanied with activation of caspase-9 and -3 were involved in the death of SK-N-SH cells. BAPTA-AM (Ca(2+) chelator) pretreatment rescued viability of AA-treated cells through abolishing phosphorylation of p38 MAPK and JNK, DeltaPsim loss and ROS generation. N-Acetylcysteine (ROS scavenger) pretreatment reduced the dissipation of DeltaPsim, but insignificantly affected AA-induced p38 MAPK and JNK activation. SB202190 (p38 MAPK inhibitor) and SP600125 (JNK inhibitor) attenuated mitochondrial depolarization, degradation of Bcl-2/Bcl-xL, and mitochondrial translocation of Bax. Transfection of specific siRNA proved that p38alpha MAPK and JNK1 were involved in modulating Bcl-2 family proteins. Taken together, our data suggest that the cytotoxicity of AA toward SK-N-SH cells is mediated through mitochondria-dependent death pathway, eliciting by AA-induced ROS generation and Ca(2+)-evoked activation of p38alpha MAPK and JNK1.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Apoptosis / drug effects*
  • Arachidonic Acid / toxicity*
  • Calcium / metabolism
  • Caspase 3 / drug effects
  • Caspase 3 / metabolism
  • Caspase 9 / drug effects
  • Caspase 9 / metabolism
  • Cell Line, Tumor
  • Cytochromes c / drug effects
  • Cytochromes c / metabolism
  • Humans
  • Membrane Potential, Mitochondrial / drug effects
  • Mitochondria / drug effects*
  • Mitochondria / metabolism
  • Mitogen-Activated Protein Kinase 8 / drug effects
  • Mitogen-Activated Protein Kinase 8 / metabolism
  • Neuroblastoma / metabolism*
  • Proto-Oncogene Proteins c-bcl-2 / drug effects
  • Proto-Oncogene Proteins c-bcl-2 / metabolism
  • RNA, Small Interfering / metabolism
  • Reactive Oxygen Species / metabolism*
  • Transfection
  • p38 Mitogen-Activated Protein Kinases / drug effects
  • p38 Mitogen-Activated Protein Kinases / metabolism

Substances

  • Proto-Oncogene Proteins c-bcl-2
  • RNA, Small Interfering
  • Reactive Oxygen Species
  • Arachidonic Acid
  • Cytochromes c
  • Mitogen-Activated Protein Kinase 8
  • p38 Mitogen-Activated Protein Kinases
  • Caspase 3
  • Caspase 9
  • Calcium