PLATELET AGGREGATION INHIBITING COMPONENTS FROM VIPERA LEBETINA SNAKE VENOM

Abstract number: P-S-272

Siigur¹ E., Samel¹ M., Tonismagi¹ K., Vija¹ H., Trummal¹ K., Aaspollu² A., Pikver³ R., Subbi³ J., Siigur¹ J.

¹¹Bioorganic Chemistry ²²Molecular Genetics ³³Chemical Physics, National Institute of Chemical Physics and Biophysics, Tallinn, Estonia

How-to-cite Siigur E, Samel M, Tonismagi K, Vija H, Trummal K, Aaspollu A, Pikver R, Subbi J, Siigur J. PLATELET AGGREGATION INHIBITING COMPONENTS FROM VIPERA LEBETINA SNAKE VENOM. J Thromb Haemost 2007; 5 Supplement 2: P-S-272

Abstract

Introduction: Snake venoms have been reported to contain a number of platelet active components including enzymes and nonenzymatic proteins and peptides that inhibit platelet aggregation (Lu et al 2005). It was demonstrated earlier in our laboratory that V. lebetina venom (Uzbekistan) contains fibrinolytic metalloproteinase lebetase (Siigur et al 1998) and L-amino acid oxidase (Tõnismägi et al 2006) that both inhibit ADP- and collagen-induced human platelet aggregation. Two platelet aggregation inhibiting proteins, heterodimeric disintegrin VLT-2 and phospholipase A2 (PLA2) are characterized in the present work.

Methods: Platelet aggregation assays were performed in human platelet-rich plasma using a Chronolog aggregometer. PLA2 was determined by the method of Marinetti (1965) using egg yolk as substrate. Molecular masses of proteins were detected by MALDI-TOF mass spectrometry.

Results: VLT-2 and PLA2 were purified from Vipera lebetina venom by size exclusion chromatography on Sephadex G-100sf, HPLC and UPLC on C18 column. Using cDNA library of the venom gland of a single V.lebetina snake the VLT-2 coding cDNAs were cloned and sequenced. VLT-2 chains are synthesized from different genes.

VLT-2 primary structure is similar to that of heterodimeric disintegrin VLO-5 from V.lebetina obtusa venom (Calvete et al 2003). VLT-2 dose-dependently inhibited collagen- induced platelet aggregation with IC50= 240 nM and ADP-induced aggregation with IC50= 480 nM. The nucleotide sequences are registered in GenBank under Accession numbers X97894 and DQ295886. PLA2 is a single chain protein with molecular mass of 13825 Da that inhibits human platelet aggregation.

Conclusions: Vipera lebetina venom is a good source of biomedically active agents.

References: Lu et al (2005) J Thromb Haemost 3,1791-1799; Calvete et al (2003) Biochem J 372,725-734; Siigur et al (1996) BBRC 224,229-236; Siigur et al (1998) Thromb Res 90, 39-49. The work was supported by Estonian Science Foundation Grants No. 5938 and 7251.

To cite this abstract use the following format:

Journal of Thrombosis and Haemostasis 2007; Volume 5, Supplement 2: abstract number

Session Details

Date:	01/08/2007
Time:	00:00-00:00
Session name:	XXIst ISTH Congress
Subject:
Location:	Oxford, UK
Presentation type:
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