Metastatic Inhibitory and Radical Scavenging Efficacies of Saponins Extracted from the Brittle Star (Ophiocoma erinaceus)

Abstract

Echinodermata use saponins in chemical defense against pathogens and predators. The molecular mechanismsof antimetastatic effects of brittle star saponins are still unknown. The present study examined antioxidantcapacity and invasive ability in HeLa carcinoma cells exposed to brittle star crude saponins. Discolorating methodswith DPPH and ABTS and expression of SOD-2 with RT-PCR were used to estimate the antioxidant activity.The anti-invasive activity of extracted saponins was examined through adhesion of HeLa cells to extracellularmatrix, wound healing and evaluation of the mRNA levels of MMP-2 and MMP-9 by real time-PCR. The resultsshowed that extracted saponins had cytotoxicity against cervical cancer cells and ABTS and DPPH scavengingproperties with IC50 values of 604.5, 1012 μg/ml, respectively. Further, we found that, in wound healing assay,brittle star saponins could prevent invasion of HeLa cells in a concentration dependent manner. Furthermore, celladhesion assay demonstrated blockage of cell attachment to extracellular matrix with an IC50 concentration of16.1μg/ml. The significant dose dependent down regulation of MMP-2 and MMP-9 in treated cells demonstratedthat isolated saponins can decline tumor metastasis in vitro. The brittle star saponins remarkably preventedcervical cancer invasion and migration associated with down regulation of matrix metalloproteinase expression.Therefore, saponins could be suggested as an anti-invasive candidate against cervical cancer and an antioxidantas well.