Inflammatory effects of snake venom myotoxic phospholipases A(2)

Autor(es)

Teixeira, C. F. P. ; Landucci, E. C. T. ; Antunes, E. ; Chacur, M. ^[4] ; Cury, Y.

• Tipo de documento: Artigo Científico
• Fonte: Toxicon; v. 42, n. 8, p. 947-962, Dec. 2003.
• Área do conhecimento: Ciências Biológicas - Farmacologia
• Assunto(s): Farmacologia Fosfolipases A Dor Venenos de origem animal Bothrops

Resumo

Snake venom phospholipases A2 (PLA2) show a remarkable functional diversity. Among their toxic activities, some display the ability to cause rapid necrosis of skeletal muscle fibers, thus being myotoxic PLA2s. Besides myotoxicity, these enzymes evoke conspicuous inflammatory and nociceptive events in experimental models. Local inflammation and pain are important characteristics of snakebite envenomations inflicted by viperid and crotalid species, whose venoms are rich sources of myotoxic PLA2s. Since the discovery that mammalian PLA2 is a key enzyme in the release of arachidonic acid, the substrate for the synthesis of several lipid inflammatory mediators, much interest has been focused on this enzyme in the context of inflammation. The mechanisms involved in the proinflammatory action of secretory PLA2s are being actively investigated, and part of the knowledge on secretory PLA2 effects has been gained by using snake venom PLA2s as tools, due to their high structural homology with human secretory PLA2s. The inflammatory events evoked by PLA2s are primarily associated with enzymatic activity and to the release of arachidonic acid metabolites. However, catalytically inactive Lys49 PLA2s trigger inflammatory and nociceptive responses comparable to those of their catalytically active counterparts, thereby evidencing that these proteins promote inflammation and pain by mechanisms not related to phospholipid hydrolysis nor to mobilization of arachidonic acid. These studies have provided a boost to the research in this field and various approaches have been used to identify the amino acid residues and the specific sites of interaction of myotoxic PLA2s with cell membranes potentially involved in the PLA2-induced inflammatory and nociceptive effects. This work reviews the proinflammatory and nociceptive effects evoked by myotoxic PLA2s and their mechanisms of action. (AU)

• Processo FAPESP: 00/12303-8 - Participação de neuropeptídeos aminoácidos excitatórios e células da glia na hiperalgesia induzida por fosfolipases A2 (Lys49 e Asp49) isoladas do veneno de serpentes (Bothrops asper)
• Beneficiário: Marucia Chacur
• Modalidade de apoio: Bolsas no Brasil - Doutorado
• Processo FAPESP: 99/08432-8 - Mecanismos centrais e perifericos da dor induzida por fosfolipases a2 (lys-49 e asp-49) isoladas do veneno de serpentes bothrops asper.
• Beneficiário: Yara Cury
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 98/00162-9 - Estudo dos mecanismos pro-inflamatorios induzidos pelos venenos de bothrops jararaca (america do sul) e bothrops asper (america central) em modelos experimentais in vivo e in vitro.
• Beneficiário: Catarina de Fatima Pereira Teixeira
• Modalidade de apoio: Auxílio à Pesquisa - Regular