Time-course changes of catabolic proteins following muscle atrophy induced by dexamethasone

Author(s)

Macedo, Anderson G. ^[1] ; Krug, Andre Luis O. ^[1] ; Souza, Lidiane M. ^[2] ; Martuscelli, Aline M. ^[1] ; Constantino, Paula B. ^[1] ; Zago, Anderson S. ^[2] ; Rush, James W. E. ^[3] ; Santos, Carlos F. ^[4] ; Amaral, Sandra L. ^{[1, 2]}

Affiliation

^[1] Fed Univ Sao Carlos UFSCAR, Dept Physiol Sci, PIPGCF UFSCar UNESP, Joint Grad Program Physiol Sci, Sao Carlos, SP - Brazil

^[2] Univ Estadual Paulista UNESP, Dept Phys Educ, Bauru - Brazil

^[3] Univ Waterloo, Fac Appl Hlth Sci, Dept Kinesiol, Waterloo, ON N2L 3G1 - Canada

^[4] Univ Sao Paulo, Bauru Sch Dent, Dept Biol Sci, Bauru - Brazil

• Document type: Journal article
• Source: Steroids; v. 107, p. 30-36, MAR 2016.
• Web of Science Citations: 9

Abstract

This study was designed to describe the time-course changes of catabolic proteins following muscle atrophy induced by 10 days of dexamethasone (DEX). Rats underwent DEX treatment for 1, 3, 5, 7 and 10 days. Body weight (BW) and lean mass were obtained using a dual energy X-ray absorptiometry (DEXA) scan. Muscle ringer fingerl (MuRF-1), atrogin-1 and myostatin protein levels were analyzed in the tibialis anterior (TA), flexor hallucis longus (FHL) and soleus muscles. DEX treatment reduced lean mass since day-3 and reduced BW since day-5. Specific muscle weight reductions were observed after day-10 in TA (-23%) and after day-5 in FHL (-16%, -17% and -29%, for days 5, 7 and 10, respectively). In TA, myostatin protein level was 36% higher on day-5 and its values were normalized in comparison with controls on day-10. MuRF-1 protein level was increased in TA muscle from day-7 and in FHL muscle only on day-10. This study suggests that DEX-induced muscle atrophy is a dynamic process which involves important signaling factors over time. As demonstrated by DEXA scan, lean mass declines earlier than BW and this response may involve other catabolic proteins than myostatin and MuRF-1. Specifically for TA and FHL, it seems that myostatin may trigger the catabolic process, and MuRF-1 may contribute to maintain muscle atrophy. This information may support any intervention in order to attenuate the muscle atrophy during long period of treatment. (C) 2015 Elsevier Inc. All rights reserved. (AU)

• FAPESP's process: 12/21820-3 - The role of resistance exercise on muscle atrophy induced by Dexamethasone
• Grantee: André Luis de Oliveira Krug
• Support Opportunities: Scholarships in Brazil - Master
• FAPESP's process: 11/21522-0 - Role of renin-antiotensin-system and simpathetic nervous system in dexamethasone-induced hypertension: preventive effects of exercise training
• Grantee: Sandra Lia do Amaral Cardoso
• Support Opportunities: Regular Research Grants