Research Article Effect of High-Fat Diet upon Inflammatory Markers and Aortic Stiffening in Mice Andre Bento Chaves Santana, 1 Thais Cristina de Souza Oliveira, 1 Barbara Lobo Bianconi, 1 Valerio Garrone Barauna, 2 Ed Wilson Cavalcante Oliveira Santos, 3 Tatiana P. Alves, 1 Juliane Cristina S. Silva, 1 Patricia Fiorino, 4 Primavera Borelli, 3 Maria Claudia Costa Irigoyen, 2 José Eduardo Krieger, 2 and Silvia Lacchini 1 1 Institute of Biomedical Sciences, University of Sao Paulo, 05508-000 Sao Paulo, SP, Brazil 2 Heart Institute, University of Sao Paulo Medical School, 05403-900 Sao Paulo, SP, Brazil 3 Faculty of Pharmaceutical Sciences, University of Sao Paulo, 05508-000 Sao Paulo, SP, Brazil 4 Health, Biology and Science Center, Mackenzie University, 01302-907 Sao Paulo, SP, Brazil Correspondence should be addressed to Silvia Lacchini; lacchini@icb.usp.br Received 25 November 2013; Revised 17 March 2014; Accepted 20 March 2014; Published 11 June 2014 Academic Editor: Senthil K. Venugopal Copyright © 2014 Andre Bento Chaves Santana et al. Tis is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Changes in lifestyle such as increase in high-fat food consumption are an important cause for vascular diseases. Te present study aimed to investigate the involvement of ACE and TGF- in the aorta stifness induced by high-fat diet. C57BL/6 male mice were divided in two groups according to their diet for 8 weeks: standard diet (ST) and high-fat diet (HF). At the end of the protocol, body weight gain, adipose tissue content, serum lipids and glucose levels, and aorta morphometric and biochemical measurements were performed. Analysis of collagen fbers by picrosirius staining of aorta slices showed that HF diet promoted increase of thin (55%) and thick (100%) collagen fbers deposition and concomitant disorganization of these fbers orientations in the aorta vascular wall (50%). To unravel the mechanism involved, myeloperoxidase (MPO) and angiotensin I converting enzyme (ACE) were evaluated by protein expression and enzyme activity. HF diet increased MPO (90%) and ACE (28%) activities, as well as protein expression of ACE. TGF- was also increased in aorta tissue of HF diet mice afer 8 weeks. Altogether, we have observed that the HF diet-induced aortic stifening may be associated with increased oxidative stress damage and activation of the RAS in vascular tissue. 1. Introduction Aortic disease is an important cause of mortality world- wide, which may be exemplifed by vascular aneurysm, atherosclerotic lesion, and vascular stifening [1]. Lifestyle characteristics such as obesity promote adverse efects on the vascular system by increasing aortic stifness [2]. Increased collagen deposition leads to stifening of the arterial wall, compromising vascular distensibility and con- tributing to a feedback of the hypertensive process [3]. Te tunica adventitia (the outmost layer of the vessels) is com- posed of connective tissue whose main matrix component is collagen fbers. Some lamellae of elastic fbers can also be found in this network [4]. Te outer layers of the tunica adventitia are rich in collagen types I and III which are produced by local fbroblasts [5]. In light microscopy, these layers are not distinct but integrate with the connective tissue around the outside of the vessel, helping it to maintain its vascular structure. Te deposition of collagen has a functional role in the adventitia maintaining, strengthening the vessel wall to prevent its rupture. Collagen is abundantly deposited in extracellular matrix (ECM) acting in maintaining the integrity and resistance of vascular wall [6]. Arterial stifening involves mechanisms of ECM remod- eling, promoted by increased collagen deposition, and this mechanism involves both endothelial cells from intima and Hindawi Publishing Corporation BioMed Research International Volume 2014, Article ID 914102, 12 pages http://dx.doi.org/10.1155/2014/914102