Could mesenchymal stem cell therapy help in the treatment of muscle damage caused by Bothrops alternatus venom

EnglishThe aim of this study was to evaluate the use of mesenchymal stem cells (MSC) in the treatment of myonecrosis induced by Bothrops alternatus venom in rats. Seventy-five male adult Wistar rats were divided into three experimental groups. G1 and G2 were injected in the gastrocnemius muscle with 120μg of B. alternatus venom, while G3 received 200μL of PBS only. Three days after the venom injection, 12 rats from G1 were treated with 5.0 x 106 MSC in PBS, whereas G2 and G3 rats received PBS. Every three days, blood and muscle samples of five animals from each group were taken for serum biochemical and pathological analyses. Histological examinations showed more intense muscle lesions following MSC treatment, characterized by disorganization and loss of muscle fibers, with focal necrosis and inflammatory infiltration by mononuclear cells. In conclusion, the use of MSC for the treatment of local damage caused by inoculation of B. alternatus venom impaired muscle regeneration and interfered in the healing process. Key words: Viperidae envenomation; stem cells; rats; myonecrosis; muscular repair portuguesO objetivo do presente trabalho foi avaliar a utilizacao das celulas tronco mesenquimais (MSC) no tratamento da mionecrose induzida pelo veneno de Bothrops alternatus em ratos. 75 ratos Wistar adultos foram distribuidos em tres grupos experimentais. G1 e G2 receberam 120μg de veneno de B. alternatus, enquanto o G3 recebeu apenas 200μL de PBS. Tres dias apos a administracao do veneno, os ratos do grupo G1 foram tratados com 5.0 x 106 MSC, enquanto G2 e G3 receberam exclusivamente PBS. A cada tres dias, amostras de sangue e tecido muscular foram coletadas de cinco animais de cada grupo para avaliacao bioquimica serica e patologica, respectivamente. A analise histologica revelou lesao muscular mais intensa apos a aplicacao das MSC, caracterizada pela desorganizacao e perdas das fibras musculares, com necrose focal e infiltrado inflamatorio mononuclear. E possivel concluir que a utilizacao das MSC para o tratamento da lesao local causada pela inoculacao do veneno B. alternatus deteriorou a regeneracao muscular e interferiu com o processo de cicatrizacao. Palavras-chave: envenenamento por cobra; celulas tronco; ratos; mionecrose; reparacao muscular