VOLUME 70 : 2022

The Philippines is home to various species of spiders which venom is a potential source of bioactive compounds that are viable drug candidates against human disease such as cancer. Previously, it was reported that components of Philippine spider venom possess cytotoxic activities, however, the mechanism of this bioactivity is not yet explained. In this study, we attempted to look at one possible mechanism of the spider venom cytotoxicity which is anti-angiogenic.

The antiangiogenic activity of the Philippine Theraphosidae spider venom fractions were evaluated based on four parameters: vascular density, vessel length density, average vessel diameter, and bifurcation points. Venom extraction was done by electrostimulation. Collected venom was fractionated using reverse-phase high-performance liquid chromatography (RP-HPLC). Fractions were tested in an in ovo duck chorioallantoic membrane (CAM) assay. Angiogenesis were observed over a period of 24 hours. Data were processed using Image J and analyzed using GraphPad Prism 9.

Our results showed several peak fractions from the mid-polar and polar fraction clusters to possess antiangiogenic activity. The mid polar peak fractions 3 and 4 exhibited significant antiangiogenic activity wherein reducing vascular density and bifurcation points were observed at higher concentrations. Based on these results, we conclude that these bioactive fractions which contain antiangiogenic compounds may be potential sources of druggable molecules against cancer. Furthermore, we recommend that composition and structural analysis be done to identify the antiangiogenic components