NADPH Oxidase Plays a Role on Ethanol-Induced Hypertension and Reactive Oxygen Species Generation in the Vasculature

Author(s)

Marchi, Katia Colombo ; Ceron, Carla Speroni ; Muniz, Jaqueline J. ; De Martinis, Bruno S. ; Tanus-Santos, Jose E. ; Tirapelli, Carlos Renato

• Document type: Journal article
• Source: ALCOHOL AND ALCOHOLISM; v. 51, n. 5, p. 522-534, SEP 2016.
• Web of Science Citations: 15

Abstract

Investigate the role of NADPH oxidase on ethanol-induced hypertension and vascular oxidative stress. Male Wistar rats were treated with ethanol (20% v/v). Apocynin (10 mg/kg/day, i.p.) prevented ethanol-induced hypertension. The increased contractility of endothelium-intact and endothelium-denuded aortic rings from ethanol-treated rats to phenylephrine was prevented by apocynin. Ethanol consumption increased superoxide anion (O-2 (-)) generation and lipid peroxidation and apocynin prevented these responses. The decrease on plasma and vascular nitrate/nitrite (NOx) levels induced by ethanol was not prevented by apocynin. Treatment with ethanol did not affect aortic levels of hydrogen peroxide (H2O2) or reduced glutathione (GSH). Ethanol did not alter the activities of xanthine oxidase (XO), superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx). Ethanol increased the expression of Nox1, PKC delta, nNOS, SAPK/JNK and SOD2 in the rat aorta and apocynin prevented these responses. No difference on aortic expression of Nox2, Nox4, p47phox, Nox organizer 1 (Noxo1), eNOS and iNOS was detected after treatment with ethanol. Ethanol treatment did not alter the phosphorylation of SAPK/JNK, p38MAPK, c-Src, Rac1 or PKC delta. The major new finding of our study is that the increased vascular generation of reactive oxygen species (ROS) induced by ethanol is related to increased vascular Nox1/NADPH oxidase expression. This mechanism is involved in vascular dysfunction and hypertension induced by ethanol. Additionally, we conclude that ethanol consumption induces the expression of different proteins that regulate vascular contraction and growth and that NADPH oxidase-derived ROS play a role in such response. The key findings of our study are that ethanol-induced hypertension is mediated by NADPH oxidase. Moreover, increased vascular Nox1 expression is related to the generation of reactive oxygen species (ROS) by ethanol. Finally, ROS induced by ethanol increase the expression of the regulatory vascular proteins. (AU)

• FAPESP's process: 12/01147-2 - Role of NAD(P)H oxidase in the cardiovascular effects induced by chronic ethanol consumption.
• Grantee: Katia Colombo Marchi
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 13/15824-9 - Role of NAD(P)H oxidase in vascular dysfunction and increased blood pressure induced by ethanol consumption: involvement of oxidative stress and the vascular redox signaling
• Grantee: Carlos Renato Tirapelli
• Support Opportunities: Regular Research Grants