%0 Journal Article
%T Treatment with CB2 Agonist JWH-133 Reduces Histological Features Associated with Erectile Dysfunction in Hypercholesterolemic Mice
%A Rodrigo Araujo Fraga-Silva
%A Fabiana Pereira Costa-Fraga
%A Fabrizio Montecucco
%A Younouss Faye
%A Silvia Quintao Savergnini
%A S¨¦bastien Lenglet
%A Fran£¿ois Mach
%A Sabine Steffens
%A Nikolaos Stergiopulos
%A Robson Augusto Souza dos Santos
%A Rafaela Fernandes da Silva
%J Journal of Immunology Research
%D 2013
%R 10.1155/2013/263846
%X Hypercholesterolemia is one of the most important risk factors for erectile dysfunction, mostly due to the impairment of oxidative stress and endothelial function in the penis. The cannabinoid system might regulate peripheral mechanisms of sexual function; however, its role is still poorly understood. We investigated the effects of CB2 activation on oxidative stress and fibrosis within the corpus cavernosum of hypercholesterolemic mice. Apolipoprotein-E-knockout mice were fed with a western-type diet for 11 weeks and treated with JWH-133 (selective CB2 agonist) or vehicle during the last 3 weeks. CB2 receptor expression, total collagen content, and reactive oxygen species (ROS) production within the penis were assessed. In vitro corpus cavernosum strips preparation was performed to evaluate the nitric oxide (NO) bioavailability. CB2 protein expression was shown in cavernosal endothelial and smooth muscle cells of wild type and hypercholesterolemic mice. Treatment with JWH-133 reduced ROS production and NADPH-oxidase expression in hypercholesterolemic mice penis. Furthermore, JWH-133 increased endothelial NO synthase expression in the corpus cavernosum and augmented NO bioavailability. The decrease in oxidative stress levels was accompanied with a reduction in corpus cavernosum collagen content. In summary, CB2 activation decreased histological features, which were associated with erectile dysfunction in hypercholesterolemic mice. 1. Introduction Penile erection occurs when there is a relaxation of the smooth muscle cells in cavernosal arterioles and surrounding sinuses, resulting in increased blood flow into the penis associated with a pressure-dependent veno-occlusive mechanism within the sinuses controlling the blood outflow [1, 2]. The major mechanism responsible for ED is an increase in the tone and/or contractility of the smooth muscle within the corpus cavernosum and penile arteries [3], which is mostly due to diminished production and function of nitric oxide (NO) and other vasoprotective factors, which is compounded by the exaggerated production of reactive oxygen species (ROS) and vasoconstrictors [4, 5]. Hypercholesterolemia is one of the most important risk factors for the development of ED [5]. This phenotype produces various functional and structural alterations in the vasculature, frequently leading to the development of atherosclerosis [1, 4]. These vascular changes alter tissue perfusion and can impair the ability of arteries to respond to vasodilators factors [5¨C7]. Chronically, this impairment may result in cavernosal fibrosis, which
%U http://www.hindawi.com/journals/jir/2013/263846/