TY - JOUR
T1 - Hyperglycemia and reactive oxygen species mediate apoptosis in aortic endothelial cells through Janus kinase 2
AU - Tawfik, Amany
AU - Jin, Liming
AU - Banes-Berceli, Amy K.L.
AU - Caldwell, Ruth B.
AU - Ogbi, Safia
AU - Shirley, Amanda
AU - Barber, Dwayne
AU - Catravas, John D.
AU - Stern, David M.
AU - Fulton, David
AU - Caldwell, R. William
AU - Marrero, Mario B.
PY - 2005/11
Y1 - 2005/11
N2 - The generation of reactive oxygen species (ROS) has been implicated in the perturbation of endothelial function and cell death. However, the specific signaling pathways which mediate and modifying this response have not been fully elucidated. Therefore, in this study we tested the hypothesis that activation of JAK2 is involved in the aortic endothelial cell (EC) response to ROS. When ECs were exposed to HG (25 mM) for 6 h or ROS (i.e., H2O2 (100 μM)) for 1 h and returned to normal medium we found a decrease in cell density and morphologic signs of apoptosis. Furthermore, incubation of ECs with HG and H2O2 also resulted in the tyrosine phosphorylation of JAK2. In addition, pretreatment of ECs with AG-490, an inhibitor of JAK2, prevented nuclear fragmentation, whereas inhibitors of Jun kinase (SP 600125), MAP kinase (PD 98059), Src kinase (PP2) or PI-3 kinase (wortmannin) were without effect. Finally, immunoblot analysis of caspase-3 and PARP cleavage confirmed a role for activation of JAK2 in both HG- or ROS-induced apoptosis, based on inhibition by either AG-490 or adenoviral transfection with a dominant-negative JAK2 mutant. In conclusion the activation of JAK2 plays a pivotal role in oxidant stress-induced commitment of ECs to apoptosis, based on studies with HG and H2O2.
AB - The generation of reactive oxygen species (ROS) has been implicated in the perturbation of endothelial function and cell death. However, the specific signaling pathways which mediate and modifying this response have not been fully elucidated. Therefore, in this study we tested the hypothesis that activation of JAK2 is involved in the aortic endothelial cell (EC) response to ROS. When ECs were exposed to HG (25 mM) for 6 h or ROS (i.e., H2O2 (100 μM)) for 1 h and returned to normal medium we found a decrease in cell density and morphologic signs of apoptosis. Furthermore, incubation of ECs with HG and H2O2 also resulted in the tyrosine phosphorylation of JAK2. In addition, pretreatment of ECs with AG-490, an inhibitor of JAK2, prevented nuclear fragmentation, whereas inhibitors of Jun kinase (SP 600125), MAP kinase (PD 98059), Src kinase (PP2) or PI-3 kinase (wortmannin) were without effect. Finally, immunoblot analysis of caspase-3 and PARP cleavage confirmed a role for activation of JAK2 in both HG- or ROS-induced apoptosis, based on inhibition by either AG-490 or adenoviral transfection with a dominant-negative JAK2 mutant. In conclusion the activation of JAK2 plays a pivotal role in oxidant stress-induced commitment of ECs to apoptosis, based on studies with HG and H2O2.
KW - Apoptosis
KW - Endothelial cells
KW - JAK2
UR - http://www.scopus.com/inward/record.url?scp=27744534805&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=27744534805&partnerID=8YFLogxK
U2 - 10.1016/j.vph.2005.08.018
DO - 10.1016/j.vph.2005.08.018
M3 - Article
C2 - 16257269
AN - SCOPUS:27744534805
SN - 1537-1891
VL - 43
SP - 320
EP - 326
JO - Vascular Pharmacology
JF - Vascular Pharmacology
IS - 5
ER -