Biological Effects of Secretory Phospholipase A2 from Venoms of Gloydius blomhoffii and Gloydius halys.

Gloydius blomhoffii and Gloydius halys venoms contain considerable amounts of group IIA secretory phospholipase (sPLA2). We studied the cytotoxic effects of some fractions from these venoms on the A549 lung adenocarcinoma cell line. G. blomhoffii venom fraction 16 and G. halys venom fraction 22 exhibited significant cytotoxicity against A549 cells (cell viability 10.7 ± 1.5% and 11.7 ± 2.7%, respectively). The sPLA2-sensitive melanoma SK-MEL-2 cell line and the sPLA2 inhibitor varespladib were used for sPLA2 identification and evaluation of its cytotoxicity in these fractions. Cell viability in the presence of the inhibitor increased by 26.4% (fraction 16) and 13% (fraction 22), which confirms a link between the cytotoxic effect and the enzymatic activity of sPLA2 in the fractions examined. The two protein components were further identified as acidic phospholipases A2.