Cytotoxic and anti-proliferative activity of aqueous yerba mate (ilex paraguariansis) extracts on adenocarcinoma (caco-2) cell line

Abstract

Yerba Mate, a beverage prepared from the leaves and stems of Ilex paraguariensis is widely consumed due to increasing reported health benefits. Yerba Mate is rich in several bioactive compounds that have been found to act as free radical scavengers. The relationship between Yerba Mate and cancer has not been studied extensively compared with other herbal teas. Previous studies have suggested an anti-proliferative activity of Yerba Mate ethanolic extracts on several human cancer cell lines. In this study, we studied the effect of the aqueous Yerba Mate extract on CaCo-2 cell line. Trypan Blue assays showed a decrease in viability of CaCo-2 cell line from 80% to 16% at 24 hours and from 80% to 14% at 48 hours. This extract exhibited a dose dependent effect. The aqueous Yerba Mate extract also had strong anti-proliferative activity with IC50 approximately 0.220, 0.138, 0.019 mg/mL for CaCo-2 at 24, 48 and 72 hours respectively as tested by the WST-1 proliferation kit. Annexin V/PI assays showed that cell death was most probably caused by activation of apoptosis pathway. At the highest concentration of 4.5 mg/mL, there was a decrease in cell viability at 24 hours from around 90% to 64%, with an increase in early apoptotic cells from 3.5% to 8.26% and late apoptotic cells from 5.2 to 26%. At 48 hours, viability decreased from around 90% to around 58.5%, with an increase in early apoptotic cells increased from 4.2% to 12.79% and increase in late apoptotic cells increased from 4.1% to 17.1%. This study highlights the potential of Yerba Mate as a potential target for future drug development research.