title: TLR4 signaling protects from excessive muscular damage induced by Bothrops jararacussu snake venom.
abstract: Immune cells and skeletal muscle express Toll-like receptors (TLRs) that participate as sensors of tissue injury triggering signals for activation of innate and adaptive immune responses. This study aimed to investigate the involvement of TLR4 in the process of skeletal muscle repair. Muscular injury was induced by injection of 0.6 mg/kg of Bothrops jararacussu snake venom in the gastrocnemius muscle of C3H/HeJ mice that express a non-functional TLR-4 receptor and C3H/HeN mice with functional receptor. TLR4-deficient mice had persistent muscular inflammation with few F4/80 macrophages at onset but increased MMP9 activity and collagen deposition during resolution of injury. Since such effect was not observed in the mouse strain with functional receptor it is concluded that TLR4 signaling exerts a protective role preventing from excessive muscular damage induced by B. jararacussu venom.
authors.affiliation: Department of Immunobiology, Institute of Biology, Fluminense Federal University, Niteroi, Rio de Janeiro 24020-141, Brazil.
authors.forename: Eustaquio Luiz
authors.initials: EL
authors.lastname: Paiva-Oliveira
authors.forename: Rafael
authors.initials: R
authors.lastname: Ferreira da Silva
authors.forename: Paulo Emílio
authors.initials: PE
authors.lastname: Correa Leite
authors.forename: José Carlos
authors.initials: JC
authors.lastname: Cogo
authors.forename: Thereza
authors.initials: T
authors.lastname: Quirico-Santos
authors.forename: Jussara
authors.initials: J
authors.lastname: Lagrota-Candido
mesh_terms: D000818:Animals; D017837:Bothrops; D003402:Creatine Kinase / Q000378:metabolism; D003435:Crotalid Venoms / Q000633:toxicity*; D007150:Immunohistochemistry; D008297:Male; D051379:Mice; D008809:Mice, Inbred C3H; D018482:Muscle, Skeletal / Q000187:drug effects* / Q000201:enzymology / Q000293:injuries; D015398:Signal Transduction; D051197:Toll-Like Receptor 4 / Q000378:metabolism*
chemical_list: D003435:Crotalid Venoms; C495345:TLR4 protein, human; D051197:Toll-Like Receptor 4; D003402:Creatine Kinase