Hydrogen peroxide increases [ 3 H]-2-deoxyglucose uptake via MAPKs, cPLA 2 , and NF-κB signaling pathways in mouse embryonic stem cells

Abstract

Hydrogen peroxide (H 2 O 2 ) has been shown to act as a signaling molecule that is involved in many cellular functions. This study investigated the effect of H 2 O 2 on the [ 3 H]-2-deoxyglucose (2-DG) uptake and its related signaling pathways in mouse embryonic stem (ES) cells. H 2 O 2 significantly increased the level of 2-DG uptake in a time- (> 4 hr) and concentration- (>10 -4 M) dependent manner due to an increase in V max but not K m . Indeed, H 2 O 2 increased the mRNA and protein level of glucose transporter 1 (GLUT 1). PD 98059 (a p44/42 MAPKs inhibitor, 10 -5 M), SB 203580 (a p38 MAPK inhibitor, 10 -6 M), and SP 600125 (a SAPK/JNK inhibitor, 10 -6 M) blocked the H 2 O 2 -induced increase in 2-DG uptake. H 2 O 2 also increased phosphorylation of p44/42 mitogen activated protein kinases (MAPKs), p38 MAPK, and stress-activated protein kinase/Jun-N-terminal kinase (SAPK/JNK). In addition, H 2 O 2 stimulated the translocation of cytosolic phospholipase A 2 (cPLA 2 ) from the cytosolic fraction to the membrane fraction, the release of arachidonic acid, and the activation of NF-κB. AACOCF 3 or mepacrine (cPLA 2 inhibitors, 10 -6 M), SN 50 (NF-κB nucleus translocation inhibitor, 500 ng/ml) or Bay11-7082 (a IκB-α phosphorylation inhibitor, 2×10 -5 M) blocked the H 2 O 2 -induced increase in 2-DG uptake. H 2 O 2 increased the protein level of glucose transporter 1 (GLUT 1), which was blocked by PD 98059, SB 203580, SP 600125, mepacrine, or Bay11-7082. In conclusion, H 2 O 2 increases the 2-DG uptake via MAPKs, cPLA 2 , and NF-κB signaling pathways in mouse ES cells. Copyright © 2007 S. Karger AG.