Table of Contents
ISRN Neuroscience
Volume 2013, Article ID 423931, 10 pages
Research Article

Myosins Are Differentially Expressed under Oxidative Stress in Chronic Streptozotocin-Induced Diabetic Rat Brains

1Institute of Genetics and Biochemistry, Federal University of Uberlândia, Uberlândia, MG, Brazil
2Federal University of Juiz de Fora, Governador Valadares, MG, Brazil
3Federal University of Juiz de Fora, Juiz de Fora, MG, Brazil
4Department of Chemistry, Physic, and Mathematic, University of Ribeirão Preto, Ribeirão Preto, SP, Brazil

Received 5 June 2013; Accepted 17 August 2013

Academic Editors: H. Ochi, A. Unal, and A. Witting

Copyright © 2013 Luciana Karen Calábria et al. This 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.


Diabetes mellitus is a disease characterized by persistent hyperglycemia, which may lead to brain tissue damage due to oxidative stress and also contributes to neuronal death and changes in synaptic transmission. This study evaluated the effect of oxidative stress and the use of antioxidants supplementation on myosins expression levels in the brains of chronic diabetic rats induced by streptozotocin. Lipid peroxidation, antioxidant enzymes activities, and myosins-IIB and -Va expressions at transcriptional and translational levels were examined after 90 days induction. The chronic effect of the diabetes led to the upregulation of superoxide dismutase (SOD) and catalase (CAT) activities, and the downregulation of glutathione peroxidase (GPx), but there was no statistically significant increase in the malondialdehyde (MDA) levels. These alterations were accompanied by high myosin-IIB and low myosin-Va expressions. Although the antioxidant supplementation did not interfere on MDA levels, the oxidative stress caused by chronic hyperglycemia was reduced by increasing SOD and restoring CAT and GPx activities. Interestingly, after supplementation, diabetic rats recovered only myosin-Va protein levels, without interfering on myosins mRNA levels expressed in diabetic rat brains. Our results suggest that antioxidant supplementation reduces oxidative stress and also regulates the myosins protein expression, which should be beneficial to individuals with diabetes/chronic hyperglycemia.