Anticoagulant Activity of Naja nigricollis Venom Is Mediated by Phospholipase A2 Toxins and Inhibited by Varespladib

Autor: Freek J. Vonk, Arif Arrahman, Nicholas R. Casewell, Jeroen Kool, Mark C. Wilkinson, Kristina B.M. Still, Govert W. Somsen, Taline D. Kazandjian
Přispěvatelé: BioAnalytical Chemistry, AIMMS, Chemistry and Pharmaceutical Sciences
Jazyk: angličtina
Rok vydání: 2021
Předmět:
Zdroj: Toxins, 13(5):302, 1-20. Multidisciplinary Digital Publishing Institute (MDPI)
Toxins, Vol 13, Iss 302, p 302 (2021)
Toxins
Volume 13
Issue 5
Kazandjian, T D, Arrahman, A, Still, K B M, Somsen, G W, Vonk, F J, Casewell, N R, Wilkinson, M C & Kool, J 2021, ' Anticoagulant Activity of Naja nigricollis Venom Is Mediated by Phospholipase A2 Toxins and Inhibited by Varespladib ', Toxins, vol. 13, no. 5, 302, pp. 1-20 . https://doi.org/10.3390/toxins13050302
ISSN: 2072-6651
Popis: Bites from elapid snakes typically result in neurotoxic symptoms in snakebite victims. Neurotoxins are, therefore, often the focus of research relating to understanding the pathogenesis of elapid bites. However, recent evidence suggests that some elapid snake venoms contain anticoagulant toxins which may help neurotoxic components spread more rapidly. This study examines the effects of venom from the West African black-necked spitting cobra (Naja nigricollis) on blood coagulation and identifies potential coagulopathic toxins. An integrated RPLC-MS methodology, coupled with nanofractionation, was first used to separate venom components, followed by MS, proteomics and coagulopathic bioassays. Coagulation assays were performed on both crude and nanofractionated N. nigricollis venom toxins as well as PLA2s and 3FTx purified from the venom. Assays were then repeated with the addition of either the phospholipase A2 inhibitor varespladib or the snake venom metalloproteinase inhibitor marimastat to assess whether either toxin inhibitor is capable of neutralizing coagulopathic venom activity. Subsequent proteomic analysis was performed on nanofractionated bioactive venom toxins using tryptic digestion followed by nanoLC-MS/MS measurements, which were then identified using Swiss-Prot and species-specific database searches. Varespladib, but not marimastat, was found to significantly reduce the anticoagulant activity of N. nigricollis venom and MS and proteomics analyses confirmed that the anticoagulant venom components mostly consisted of PLA2 proteins. We, therefore, conclude that PLA2s are the most likely candidates responsible for anticoagulant effects stimulated by N. nigricollis venom.
Databáze: OpenAIRE