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.
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.
Chen
Ku-Chung
KC
Institute of Biomedical Sciences, National Sun Yat-Sen University-Kaohsiung Medical University Joint Research Center, National Sun Yat-Sen University, Kaohsiung 804, Taiwan.
Chang
Long-Sen
LS
D017209:Apoptosis / Q000187:drug effects*; D016718:Arachidonic Acid / Q000633:toxicity*; D002118:Calcium / Q000378:metabolism; D053148:Caspase 3 / Q000187:drug effects / Q000378:metabolism; D053453:Caspase 9 / Q000187:drug effects / Q000378:metabolism; D045744:Cell Line, Tumor; D045304:Cytochromes c / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D008928:Mitochondria / Q000187:drug effects* / Q000378:metabolism; D048055:Mitogen-Activated Protein Kinase 8 / Q000187:drug effects / Q000378:metabolism; D009447:Neuroblastoma / Q000378:metabolism*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000187:drug effects / Q000378:metabolism; D034741:RNA, Small Interfering / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism*; D014162:Transfection; D048051:p38 Mitogen-Activated Protein Kinases / Q000187:drug effects / Q000378:metabolism
D019253:Proto-Oncogene Proteins c-bcl-2; D034741:RNA, Small Interfering; D017382:Reactive Oxygen Species; D016718:Arachidonic Acid; D045304:Cytochromes c; D048055:Mitogen-Activated Protein Kinase 8; D048051:p38 Mitogen-Activated Protein Kinases; D053148:Caspase 3; D053453:Caspase 9; D002118:Calcium