title: Effects of alternagin-C from Bothrops alternatus on gene expression and activity of metalloproteinases in regenerating skeletal muscle.
abstract: 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.
authors.affiliation: Department of Physical Therapy, Federal University of São Carlos, Rodovia Washington Luís, Km 235, CEP 13565-905 São Carlos, São Paulo, Brazil.
authors.forename: João Luiz Quagliotti
authors.initials: JL
authors.lastname: Durigan
authors.forename: Sabrina Messa
authors.initials: SM
authors.lastname: Peviani
authors.forename: Thiago Luiz
authors.initials: TL
authors.lastname: Russo
authors.forename: Gabriel Borges
authors.initials: GB
authors.lastname: Delfino
authors.forename: Juliana Uema
authors.initials: JU
authors.lastname: Ribeiro
authors.forename: Márcia Regina
authors.initials: MR
authors.lastname: Cominetti
authors.forename: Heloisa Sobreiro
authors.initials: HS
authors.lastname: Selistre-de-Araujo
authors.forename: Tania Fátima
authors.initials: TF
authors.lastname: Salvini