Effects of p38 and p42/p44 CCDPK signaling on H2O2-induced apoptosis in bovine aortic endothelial cells.
OBJECTIVE
To investigate the effects of p38 and p42/p44 Ca(2+)-calmodulin dependent protein kinases (CCDPK) signaling on hydroperoxide (H2O2)-induced apoptosis in cultured bovine aortic endothelial cells (BAEC).


METHODS
Morphologic changes and quantification of apoptotic cells were determined under fluorescence microscope after a 24-h treatment of BAEC by H2O2. Cell viability was determined with MTT method. DNA fragmentation was visualized by agarose gel electrophoresis. The expression of phospho-p38 and phospho-p42/p44 CCDPK was measured by Western blotting.


RESULTS
H2O2 elicited typical apoptotic morphologic changes (chromatic condensation, nucleus fragmentation) and DNA fragmentation. At 100-500 mumol.L-1, incubation of BAEC with H2O2 for 24 h also induced phospho-p38 and phospho-p42/p44 CCDPK expression in a concentration-dependent manner. Interestingly, H2O2-induced apoptosis was markedly increased by preincubation with U0126, a specific p42/p44 CCDPK inhibitor. However, SB203580, a specific p38 CCDPK inhibitor, enhanced the expression of phospho-p42/p44 CCDPK induced by H2O2, but had no effect on BAEC survival.


CONCLUSIONS
p42/p44 CCDPK signaling appears to play protective roles in H2O2-induced apoptosis in BAEC, whereas p38 CCDPK is not the main signaling pathway mediating H2O2-induced cellular apoptosis.
Liu
W L
WL
Laboratory of Molecular Pharmacology, Hunan Medical University, Changsha 410078, China.
Guo
X
X
Guo
Z G
ZG
D000818:Animals; D001011:Aorta; D017209:Apoptosis / Q000187:drug effects*; D002417:Cattle; D002478:Cells, Cultured; D053938:DNA Fragmentation / Q000187:drug effects; D004730:Endothelium, Vascular / Q000166:cytology / Q000378:metabolism*; D006861:Hydrogen Peroxide / Q000494:pharmacology*; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism*; D048051:p38 Mitogen-Activated Protein Kinases
D006861:Hydrogen Peroxide; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases