Leucine Supplementation Accelerates Connective Tissue Repair of Injured Tibialis Anterior Muscle

Nutrients

Marcelo G. Pereira¹  Meiricris T. Silva¹  Eduardo O. C. Carlassara¹  Dawit A. Gon๺lves²  Paulo A. Abrahamsohn⁴  Isis C. Kettelhut²  Anselmo S. Moriscot¹  Marcelo S. Aoki³ 

[1] Department of Anatomy, Institute of Biomedical Sciences, University of Sao Paulo, Prof. Lineu Prestes Av. 2415, Sao Paulo, SP 05508-000, Brazil; E-Mails:;Department of Physiology and Biochemistry/Immunology, Ribeirao Preto Medical School, University of Sao Paulo, Bandeirantes Av. 3900, Ribeirao Preto, SP 14049-900, Brazil; E-Mails:;School of Arts, Sciences and Humanities, University of Sao Paulo, Arlindo Bettio Av. 1000, Sao Paulo, SP 03828-000, Brazil; E-Mail:;Department of Cell and Developmental Biology, Institute of Biomedical Sciences, University of Sao Paulo, Prof. Lineu Prestes Av. 1524, Sao Paulo, SP 05508-000, Brazil; E-Mail:

关键词: skeletal muscle injury;    repair;    leucine supplementation;    connective tissue;    transforming growth factor-β receptor type I;    Smad2/3;   

DOI  :  10.3390/nu6103981

来源: mdpi

【 摘 要 】

This study investigated the effect of leucine supplementation on the skeletal muscle regenerative process, focusing on the remodeling of connective tissue of the fast twitch muscle tibialis anterior (TA). Young male Wistar rats were supplemented with leucine (1.35 g/kg per day); then, TA muscles from the left hind limb were cryolesioned and examined after 10 days. Although leucine supplementation induced increased protein synthesis, it was not sufficient to promote an increase in the cross-sectional area (CSA) of regenerating myofibers (p > 0.05) from TA muscles. However, leucine supplementation reduced the amount of collagen and the activation of phosphorylated transforming growth factor-β receptor type I (TβR-I) and Smad2/3 in regenerating muscles (p < 0.05). Leucine also reduced neonatal myosin heavy chain (MyHC-n) (p < 0.05), increased adult MyHC-II expression (p < 0.05) and prevented the decrease in maximum tetanic strength in regenerating TA muscles (p < 0.05). Our results suggest that leucine supplementation accelerates connective tissue repair and consequent function of regenerating TA through the attenuation of TβR-I and Smad2/3 activation. Therefore, future studies are warranted to investigate leucine supplementation as a nutritional strategy to prevent or attenuate muscle fibrosis in patients with several muscle diseases.

【 授权许可】

CC BY   
© 2014 by the authors; licensee MDPI, Basel, Switzerland.