Inflammation is a major local feature of envenomation by bothropic
snakes being characterized by a prominent local
edema,
pain, and extensive swelling. There are
reports demonstrating that whole
Bothrops snake venoms and toxins isolated from them are able to activate
macrophages functions, such as
phagocytosis,
production of reactive
oxygen,
cytokines and
eicosanoids, however, little is known about the effects of
Bothrops alternatus (B.alpha.)
venom on
macrophages. In this
work, we evaluated the proinflammatory effects of B.alpha.
venom with in vivo and
in vitro experiments using the
Raw 264.7 cell line and
mouse peritoneal macrophages. We detected that B.alpha.
venom augments
cell permeability (2-fold), and cellular extravasation (mainly
neutrophils), increase proinflammatory
cytokines IL1 (
similar to 300-fold),
IL12 (
similar to 200-fold), and TNF alpha (
similar to 80-fold) liberation and induce the expression of
enzymes related to
lipid signaling, such as cPLA(2 alpha) and COX-2. Additionally, using
lipidomic techniques we detected that this
venom produces a release of
arachidonic acid (
similar to 10 nMol/mg.
Protein) and other
fatty acids (160 and 181 n-9c). Although much of these findings were described in inflammatory processes induced by other bothropic
venoms, here we demonstrate that B.alpha.
venom also stimulates pro-inflammatory pathways involving
lipid mediators of
cell signaling. In this sense,
lipidomics analysis of
macrophages stimulated with B.alpha.
venom evidenced that the main
free fatty acids are implicated in the inflammatory response, and also demonstrated that this
venom, is able to activate
lipid metabolism even with a low content of PLA(2).