Effects of alternagin-C from Bothrops alternatus on gene expression and activity of metalloproteinases in regenerating skeletal muscle.
This study evaluated the effects of alternagin-C (ALT-C) on mRNA levels of VEGF, MyoD and matrix metalloproteinase 2 (MMP-2) and on activity of MMPs in injured tibialis anterior (TA) muscle induced by cryolesioning in rats. Thirty-six Wistar rats (3 months old, 258.9+/-27 g) were divided into five groups: (1) control group; (2) injured TA and analyzed 3 days later; (3) injured TA treated with ALT-C and analyzed 3 days later; (4) injured TA and analyzed 7 days later and (5) injured TA treated with ALT-C and analyzed 7 days later. The injured muscle received 25 microl of ALT-C (50 nM). The injured and uninjured muscle areas were quantified by light microscopy. The MMP activity was evaluated through zymography, and mRNA of MyoD, VEGF and MMP-2 was assessed by quantitative polymerase chain reaction. ALT-C neither reduced the muscle injury area nor altered the pattern of MyoD and VEGF expression in injured muscles. However, ALT-C reduces both MMP-2 mRNA and gelatinolytic activity in injured muscles. The study indicates that ALT-C, at the tested concentrations, did not improve muscle regeneration process in rats. The effect on MMP-2 mRNA and gelatinolytic activity suggests that ALT-C changes the overall balance of ECM protein turnover during muscle regeneration.
Durigan
João Luiz Quagliotti
JL
Department of Physical Therapy, Federal University of São Carlos, Rodovia Washington Luís, Km 235, CEP 13565-905 São Carlos, São Paulo, Brazil.
Peviani
Sabrina Messa
SM
Russo
Thiago Luiz
TL
Delfino
Gabriel Borges
GB
Ribeiro
Juliana Uema
JU
Cominetti
Márcia Regina
MR
Selistre-de-Araujo
Heloisa Sobreiro
HS
Salvini
Tania Fátima
TF