Use of hyperosmolar stress to measure stress-activated protein kinase activation and function in human HTR cells and mouse trophoblast stem cells.
Embryo growth is inversely correlated with hyperosmolar stress-induced stress-activated protein kinase/jun kinase (SAPK/JNK) induction. To examine whether stress has similar effects in stem cells derived from the embryo, the authors test trophoblast stem cells. The stress response of human placental and mouse trophoblast stem cell lines are tested here. Peak phosphorylated SAPK/JNK was induced by 400 mM sorbitol at 0.5 hours. At this dose, there is an SAPK/JNK-dependent decrease in mitogenic, phosphorylated cMyc at 0.5 hours preceding an SAPK/JNK-dependent decrease in cell cycle entrance at 24 hours. At 0.5 hours, SAPK/JNK decreases terminal deoxynucleotidyltransferase dUTP nick end labeling/apoptosis at sorbitol doses from 50 mM to 400 mM and induces phosphorylated cJun prior to an SAPK/JNK-dependent, approximate 8-fold increase in apoptosis by 24 hours at 400 mM. SAPK/JNK phosphorylation peaked at 0.5 to 4 hours and largely subsided by 12 hours. Thus, total SAPK/JNK exists before stress and mediates rapid, homeostatic molecular responses that become biologic consequences after phosphorylated SAPK/JNK ends. This suggests continuity in the homeostatic mechanisms and functions of SAPK/JNK in placental lineage cells during implantation, in which SAPK/JNK is completely responsible for cell cycle arrest and largely responsible for apoptosis.
Zhong
Wenjing
W
Department of Anatomy and Cell Biology, Wayne State University School of Medicine, Detroit, Michigan, USA.
Xie
Yufen
Y
Wang
Yingchun
Y
Lewis
Jennifer
J
Trostinskaia
Anna
A
Wang
Fangfei
F
Puscheck
Elizabeth E
EE
Rappolee
Daniel Allen
DA
D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D002453:Cell Cycle / Q000187:drug effects; D002460:Cell Line; D049109:Cell Proliferation / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D053595:Embryonic Stem Cells / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism* / Q000473:pathology; D005260:Female; D006801:Humans; D048031:JNK Mitogen-Activated Protein Kinases / Q000378:metabolism*; D051379:Mice; D009997:Osmotic Pressure; D010766:Phosphorylation; D016755:Proto-Oncogene Proteins c-jun / Q000378:metabolism; D016271:Proto-Oncogene Proteins c-myc / Q000378:metabolism; D013012:Sorbitol / Q000494:pharmacology; D013997:Time Factors; D014327:Trophoblasts / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism* / Q000473:pathology
C489427:MYC protein, human; C489428:Myc protein, mouse; D016755:Proto-Oncogene Proteins c-jun; D016271:Proto-Oncogene Proteins c-myc; D013012:Sorbitol; D048031:JNK Mitogen-Activated Protein Kinases