Phospholipase A2 Inhibitor from Crotalus durissus terrificus rattlesnake: Effects on human peripheral blood mononuclear cells and human neutrophils cells

Int J Biol Macromol. 2017 Dec;105(Pt 1):1117-1125. doi: 10.1016/j.ijbiomac.2017.07.140. Epub 2017 Jul 23.

Abstract

Crotalus Neutralizing Factor (CNF) is an inhibitor of phospholipase A2 (PLA2), present in the blood plasma of Crotalus durissus terrificus snake. This inhibitor neutralizes the lethal and enzymatic activity of crotoxin, the main neurotoxin from this venom. In this study, we investigated the effects of CNF on the functionality of human peripheral blood mononuclear cells (PBMCs) and human neutrophils. The following parameters were evaluated: viability and proliferation, chemotaxis, cytokines and LTB4 production, cytosolic PLA2s activity, myeloperoxidase (MPO) and superoxide anion (O2-) production. CNF showed no toxicity on PBMCs or neutrophils, and acts by stimulating the release of TNF-α and LTB4, but neither stimulates IL-10 and IL-2 nor affects PBMCs proliferation and O2- release. In neutrophils, CNF induces chemotaxis but does not induce the release of both MPO and O2-. However, it induces LTB4 and IL-8 production. These data show the influence of CNF on PBMCs' function by inducing TNF-α and LTB4 production, and on neutrophils, by stimulating chemotaxis and LTB4 production, via cytosolic PLA2 activity, and IL-8 release. The inflammatory profile produced by CNF is shown for the first time. Our present results suggest that CNF has a role in activation of leukocytes and exert proinflammatory effects on these cell.

Keywords: Crotalus Neutralizing Factor (CNF); Inflammatory mediators; Neutrophils; PBMCs.

MeSH terms

  • Animals
  • Cell Proliferation / drug effects
  • Cell Survival / drug effects
  • Chemotaxis / drug effects
  • Crotalus*
  • Cytokines / metabolism
  • Cytosol / enzymology
  • Humans
  • Interleukin-10 / metabolism
  • Interleukin-2 / metabolism
  • Interleukin-8 / metabolism
  • Leukocytes, Mononuclear / cytology
  • Leukocytes, Mononuclear / drug effects*
  • Leukocytes, Mononuclear / metabolism
  • Leukotriene B4 / biosynthesis
  • Neutrophils / cytology
  • Neutrophils / drug effects*
  • Neutrophils / metabolism
  • Peroxidase / metabolism
  • Phospholipase A2 Inhibitors / pharmacology*
  • Superoxides / metabolism
  • Tumor Necrosis Factor-alpha / metabolism

Substances

  • Cytokines
  • Interleukin-2
  • Interleukin-8
  • Phospholipase A2 Inhibitors
  • Tumor Necrosis Factor-alpha
  • Superoxides
  • Interleukin-10
  • Leukotriene B4
  • Peroxidase