Acute exercise induce endothelial nitric oxide synthase phosphorylation via Akt and AMP-activated protein kinase in aorta of rats: Role of reactive oxygen species

作者：Barbosa Viviane A; Luciano Thais F; Marques Scherolin O; Vitto Marcelo F; Souza Daniela R; Silva Luciano A; Santos Joao Paulo A; Moreira Jose C; Dal Pizzol Felipe; Lira Fabio S; Pinho Ricardo A; De Souza Claudio T^*

来源：International Journal of Cardiology, 2013, 167(6): 2983-2988.

DOI：10.1016/j.ijcard.2012.08.050

• Exercise
• eNOS phosphorylation
• Redox modulation
• Aorta

Background: Acute exercise increases reactive oxygen species (ROS) levels, including hydrogen peroxide (H2O2). H2O2 promotes endothelial nitric oxide synthase (eNOS) activation and phosphorylation in endothelial cells. With this in mind, the present study was designed to evaluate ex vivo eNOS phosphorylation in rat aortas incubated with H2O2 and to test this hypothesis in vivo in the aortas of rats submitted to acute exercise.
Methods: For ex vivo studies, six groups of aortic tissue were formed: control, H2O2, N-acetylcysteine (NAC), LY294002, compound C, and LY294002 plus compound C. While incubation with H2O2 increased Akt, AMPK and eNOS phosphorylation, pre-incubation with NAC strongly reduced the phosphorylation of these enzymes. For in vivo studies, male Wistar rats were divided into four groups: control, cont+NAC, exercise, and exer+NAC. After a 3 h swimming session, animals were decapitated and aortas were excised for biochemical and immunoblotting analysis.
Results: Acute exercise increased superoxide levels and dichlorofluorescein (DCF) concentrations, and this increase was related to phosphorylation of Akt, AMPK and eNOS. On the other hand, use of NAC reduced superoxide levels and DCF concentration. Reduced superoxide levels and DCF in the exer+NAC group were associated with decreased Akt, AMPK and eNOS phosphorylation. These results appear to be connected with vascular function because VASP phosphorylation increased in acute exercise and decreased in exer+NAC.
Conclusion: Our results indicate that ROS induced by acute exercise play the important role of activating eNOS, a process apparently mediated by Akt and AMPK.

• 出版日期2013-9-10