In Vitro studies on effect of cocoa procyanidins on ovarian cancer using cell lines

Abstract

Over the last 400 years, cocoa and chocolate have been described as having potential medicinal value, being consumed as a beverage or eaten as food. As of today, Theobroma cacao L.(Sterculiaceae) and its products are consumed worldwide. They are of great research interest because of the concentration dependant antioxidant as well as pro-oxidant properties of some of newlinetheir polyphenolic constituents, especially procyanidins and flavan-3-ols such as catechin. Due to a possible pro-oxidant effect at high concentrations, these polyphenolic constituents have shown newlinea cytotoxic effect against various cancers. newlineThe aim of this study was to investigate the effect of cocoa procyanidins against ovarian cancer newlinein vitro. Cocoa procyanidins were extracted and enriched from non-alkalized cocoa powder. The newlinepolyphenolic content and antioxidant activity were evaluated in vitro. After treatment with newlineand#8804;1000 and#956;g/mL cocoa procyanidin-rich extract (CPRE), effect on cell viability was determined on newlinehuman epithelial ovarian cancer cell lines OAW42 and OVCAR3 and normal human dermal newlinefibroblasts in order to elucidate selective cytotoxic effect. Similarly, chemosensitization effect newlinewas determined by pre-treating cancer cell lines with extract followed by doxorubicin newlinehydrochloride treatment. The effect of treatment on cell cycle and P-glycoprotein expression was newlinedetermined using flow cytometry. The effect of CPRE treatment on intracellular reactive oxygen newlinespecies (ROS) levels was determined. Apoptotic cell death, post treatment, was evaluated newlinemicroscopically and using flow cytometry by means of annexin-PI dual staining. Levels of newlinecaspase-3 as a pro-apoptotic marker and pro-MMP2 as an invasive potential marker were newlinedetected using Western blotting. newlineThe cocoa extract showed high polyphenol and procyanidin content and antioxidant activity. newlineTreatment with extract caused cytotoxicity in OAW42 and OVCAR3 cell lines. Normal dermal newlinefibroblasts showed an increase in cell viability post treatment with the extract.