Oxidative Damage in the Aging Heart: an Experimental Rat Model
Gustavo Lenci Marques1, *, Francisco Filipak Neto2, Ciro Alberto de Oliveira Ribeiro2, Samuel Liebel2, Rogério de Fraga3, Ronaldo da Rocha Loures Bueno1
Identifiers and Pagination:Year: 2015
First Page: 78
Last Page: 82
Publisher ID: TOCMJ-9-78
Article History:Received Date: 22/2/2015
Revision Received Date: 20/3/2015
Acceptance Date: 22/8/2015
Electronic publication date: 30/10/2015
Collection year: 2015
open-access license: This is an open access article licensed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/bync/ 3.0/), which permits unrestricted, non-commercial use, distribution and reproduction in any medium, provided the work is properly cited.
Introduction: Several theories have been proposed to explain the cause of ‘aging’; however, the factors that affect this complex process are still poorly understood. Of these theories, the accumulation of oxidative damage over time is among the most accepted. Particularly, the heart is one of the most affected organs by oxidative stress. The current study, therefore, aimed to investigate oxidative stress markers in myocardial tissue of rats at different ages. Methods: Seventy-two rats were distributed into 6 groups of 12 animals each and maintained for 3, 6, 9, 12, 18 and 24 months. After euthanasia, the heart was removed and the levels of non-protein thiols, lipid peroxidation, and protein carbonylation, as well as superoxide dismutase and catalase activities were determined. Results: Superoxide dismutase, catalase activity and lipid peroxidation were reduced in the older groups of animals, when compared with the younger group. However, protein carbonylation showed an increase in the 12-month group followed by a decrease in the older groups. In addition, the levels of non-protein thiols were increased in the 12-month group and not detected in the older groups. Conclusion: Our data showed that oxidative stress is not associated with aging in the heart. However, an increase in non-protein thiols may be an important factor that compensates for the decrease of superoxide dismutase and catalase activity in the oldest rats, to maintain appropriate antioxidant defenses against oxidative insults.