jararhagin-induced pro-inflammatory cytokines in mouse experimental model

CLISSA, P.B.(1), LAING, G.L.(2), TAYLOR, M.J.(2), THEAKSTON, R.D.G.(2), MOTA, I.(1), MOURA-DA-SILVA, A.M.(1)

(1)Laboratório de Imunopatologia, Instituto Butantan, São Paulo, Brasil, (2)Liverpool School of Tropical Medicine, Liverpool, UK.

Accidents caused by Bothrops jararaca snake are characterized by haemorrhage, prominent local tissue damage, and acute inflammation, which may result in permanent sequel. Specific antivenom is not capable of neutralizing venom-induced local inflammation suggesting that venom toxins can activate endogenous mechanisms. Venom metalloproteinases are able to process pro-TNF-a and TNF-a antibodies reduced the size of metalloproteinase induced necrotic lesions in mice, suggesting the importance of cytokines on the severity of envenomation. The present study evaluates the cytokines induced by jararhagin, a metalloproteinase/disintegrin isolated from B. jararaca venom, in vitro (Murine Peritoneal Adherent Cells-MPACs) and in vivo (mouse footpad). Jararhagin induced mRNA expression for TNF-a, IL-1b and IL-6 in both MPACsand footpad systems. Soluble TNF-a (130pg/paw, after 2 hours) IL-1b (400pg/paw, after 4 hours) and IL-6 (4500pg/paw, after 4 hours) were detected in the footpad homogenates. However, in culture supernatants, jararhagin enzymatic activity degraded the cytokines and their levels were detected only after inhibition of jararhagin proteolytic activity with EDTA. The role of Jararhagin disintegrin/cystein-rich domains for the local release of cytokines was also studied using Jararhagin-C isolated from B. jararaca venom. Disintegrin/cystein rich domains play an important role in cytokine release. Levels of TNF-a were similar in mice treated with either complete jararhagin or isolated disintegrin/cystein-rich domains. A reduction of approximately 50% was observed in IL-6 and IL-1b levels after treatment with jararhagin-C in comparison with treatment using the role toxin. This study showed the presence of cytokines in a pro-inflammatory model, induced by snake venom metalloproteinases both in the cell culture and also at the site of venom injection.

Financial support: FAPESP

CORRESPONDENCE TO:

Patricia Bianca Clissa, Instituto Butantan, Laboratório de Imunopatologia, Avenida Vital Brasil, 1500, Butantan, São Paulo, SP, Brasil, CEP: 05503-900, Email: clissapb@usp.br