Role of crotoxin in coagulation: novel insights into anticoagulant mechanisms and impairment of inflammation-induced coagulation

 

Bruna Terada Gimenez1, Gabriel Neves Cezarette1, Aline de Sousa Bomfim2, Wuelton Marcelo Monteiro3,4, Elisa Maria de Sousa Russo1,2, Fabiani Gai Frantz1, Suely Vilela Sampaio1, Marco Aurelio Sartim1,5

 

1 Department of Clinical Analysis, Toxicology and Food Science, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo (USP), Ribeirão Preto, SP, Brazil.

2 Center for Cell-Based Therapy and Regional Blood Center of Ribeirão Preto, University of São Paulo (USP), Ribeirão Preto, SP, Brazil.

3 Tropical Medicine Graduate Program, Amazonas State University, Manaus, AM, Brazil.

4 Carlos Borborema Clinical Research Institute, Doutor Heitor Vieira Dourado Tropical Medicine Foundation, Manaus, AM, Brazil.

5 Basic and Applied Immunology Graduate Program, Institute of Biological Sciences, Federal University of Amazonas, Manaus, AM, Brazil

 

Abstract

Background: Snake venom phospholipases A2 (svPLA2 ) are biologically active toxins, capable of triggering and modulating a wide range of biological functions. Among the svPLA2 s, crotoxin (CTX) has been in the spotlight of bioprospecting research due to its role in modulating immune response and hemostasis. In the present study, novel anticoagulant mechanisms of CTX, and the modulation of inflammation-induced coagulation were investigated.

 

Methods: CTX anticoagulant activity was evaluated using platelet poor plasma (PPP) and whole blood (WB), and also using isolated coagulation factors and complexes. The toxin modulation of procoagulant and pro-inflammatory effects was evaluated using the expression of tissue factor (TF) and cytokines in lipopolysaccharide (LPS)-treated peripheral blood mononuclear cells (PBMC) and in WB.

 

Results: The results showed that CTX impaired clot formation in both PPP and WB, and was responsible for the inhibition of both intrinsic (TF/factor VIIa) and extrinsic (factor IXa/factor VIIIa) tenase complexes, but not for factor Xa and thrombin alone. In addition, the PLA2 mitigated the prothrombinase complex by modulating the coagulation phospholipid role in the complex. In regards to the inflammation-coagulation cross talk, the toxin was capable of reducing the production of the pro-inflammatory cytokines IL-1β, IL-6 and TNF-α, and was followed by decreased levels of TF and procoagulant activity from LPS-treated PBMC either isolated or in WB.

 

Conclusion: The results obtained in the present study recognize the toxin as a novel medicinal candidate to be applied in inflammatory diseases with coagulation disorders.

 

Keywords: Crotoxin Anticoagulant mechanism Phospholipase A2 Anti-inflammatory activity Snake venom Tissue factor Coagulation factors Coagulation complex Coagulation phospholipids Cytokines

 

Correspondence: marcosartim@hotmail.com

 

Received: 13 May 2020; Accepted: 04 November 2020; Published online: 27 November 2020.