Molecular and morphological adaptations in paretic skeletal muscle from post-stroke gerbils

• Grant number: 13/14024-9
• Support Opportunities: Scholarships in Brazil - Master
• Start date: October 01, 2013
• End date: February 28, 2015
• Field of knowledge: Health Sciences - Physiotherapy and Occupational Therapy
• Principal Investigator: Thiago Luiz de Russo
• Grantee: Andriette Camilo Turi
• Host Institution: Centro de Ciências Biológicas e da Saúde (CCBS). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil

Abstract

Stroke is considered the second most important cause of death around the world and the mainly cause of disability in adult survivors. Among the dysfunctions due to stroke, the sensorimotor ones are the most prevalent and disabling, specially the muscle weakness, whose etiology is related to skeletal muscle morphofunctional alterations, such as atrophy. Nevertheless, there is a lack in the literature about which molecular factors are involved in paretic muscle atrophy. Thus, the main objective of this study is to characterize the morphological and molecular alterations, in both paretic and non-paretic muscles, 7, 15 and 21 days post-ischemic stroke in gerbils. Seventy male adult gerbils (Meriones unguiculatus), 2-3 month, will be submitted to unilateral common carotid artery occlusion for 10 minutes using a thread of suture followed by reperfusion. Functionality will be analyzed by open field and rota rod tests on the day before surgery procedure and, then, 6, 13 and 20 days after surgery. Sham group will be performed to control the surgery procedure per se. Animals will be euthanized at 7, 14 or 21 days. Morphometric (muscle fiber cross sectional area) and morphologic analyses will be performed on tibialis anterior and soleus muscles in both hind limbs. The protein content of atrophy enzymes, such as MuRF1, atrogin-1and Fbxo40, and also of muscle mass control, myostatin, will be quantified by Western Blot. For statistical analysis, data will be submitted to homogeneity (Levene) and normality (Shapiro-Wilk) tests. In the case of parametric data, Anova one-way followed by Tukey test will be performed. Significance level will set at 5%. (AU)