Takeuchi, K.Morizane, Y.Kamami-Levy, C.Suzuki, J.Kayama, M.Cai, WenyiMiller, JoanVavvas, Demetrios2018-02-232013Takeuchi, K., Y. Morizane, C. Kamami-Levy, J. Suzuki, M. Kayama, W. Cai, J. W. Miller, and D. G. Vavvas. “AMP-Dependent Kinase Inhibits Oxidative Stress-Induced Caveolin-1 Phosphorylation and Endocytosis by Suppressing the Dissociation Between c-Abl and Prdx1 Proteins in Endothelial Cells.” Journal of Biological Chemistry 288 (28) (2013): 20581–20591.0021-9258http://nrs.harvard.edu/urn-3:HUL.InstRepos:34865298Caveolin-1 is the primary structural component of endothelial caveolae that is essential for transcellular trafficking of albumin and is also a critical scaffolding protein that regulates the activity of signaling molecules in caveolae. Phosphorylation of caveolin-1 plays a fundamental role in the mechanism of oxidant-induced vascular hyper permeability. However, the regulatory mechanism of caveolin-1 phosphorylation remains unclear. Here we identify a previously unexpected role for AMPK in inhibition of caveolin-1 phosphorylation under oxidative stress. A pharmacological activator of AMPK, 5-amino-4-imidazole carboxamide riboside (AICAR), inhibited oxidative stress-induced phosphorylation of both caveolin-1 and c-Abl, which is the major kinase of caveolin-1, and endocytosis of albumin in human umbilical vein endothelial cell. These effects were abolished by treatment with two specific inhibitors of AICAR, dipyridamole, and 5-iodotubericidin. Consistently, knockdown of the catalytic AMPKα subunit by siRNA abolished the inhibitory effect of AICAR on oxidant-induced phosphorylation of both caveolin-1 and c-Abl. Pretreatment with specific c-Abl inhibitor, imatinib mesylate, and knock down of c-Abl significantly decreased the caveolin-1 phosphorylation after H2O2 exposure and abolished the inhibitory effect of AICAR on the caveolin-1 phosphorylation. Interestingly, knockdown of Prdx-1, an antioxidant enzyme associated with c-Abl, increased phosphorylation of both caveolin-1 and c-Abl and abolished the inhibitory effect of AICAR on the caveolin-1 phosphorylation. Furthermore, co-immunoprecipitation experiment showed that AICAR suppressed the oxidant-induced dissociation between c-Abl and Prdx1. Overall, our results suggest that activation of AMPK inhibits oxidative stress-induced caveolin-1 phosphorylation and endocytosis, and this effect is mediated in part by stabilizing the interaction between c-Abl and Prdx-1.en-USAMP-activated kinase (AMPK), Caveolae, Caveolin, Endocytosis, Oxidative StressJournal Article2013-09-06Kimio Takeuchi, Yuki Morizane, Cynthia Kamami-Levy, Jun Suzuki, Maki Kayama, Wenyi Cai, Joan W Miller, and Demetrios G Vavvas2018-02-2310.1074/jbc.M113.460832