Redox-modulation, Suppression of “Oncogenic” Superoxide and Induction of Apoptosis in Burkitt’s Lymphoma Cells Using Geum urbanum L. Extracts

Abstract
Burkitt’s lymphoma is a highly aggressive type of non-Hodgkin’s lymphoma, linked to the Epstein-Barr virus, which induces oxidative stress and DNA damage in the infected cells. We investigated the cytotoxicity and redox-modulating ability of ethyl acetate (EtOAc) and n-butanol (n-BuOH) extracts from Geum urbanum L. roots and aerial parts on Burkitt`s lymphoma cells (BLC), to elucidate their impact on oxidative stress and cell survival. BLC Raji was treated with EtOAc and n-BuOH extracts to analyze: cell viability; induction of apoptosis; hydroperoxides and reactive nitrogen species (RNS) by 2’,7’-dichlorodihydrofluorescein assay; superoxide by dihydroethidium assay; total antioxidant capacity by TAC assay. All extracts suppressed cell growth and induce apoptosis. n-BuOH extracts possessed higher cytotoxicity and pro-apoptotic activity compared to EtOAc. The fractions decreased the hydroperoxides and RNS levels. There was no correlation between the DCF fluorescence in the treated cells and their viability (R = -0.3722; p > 0.05). Root extracts decreased the superoxide level, while the leaf extracts did not. There was a good correlation between the dihydroethidium fluorescence in the treated cells and their viability (R = 0.9843; p < 0.01). All extracts increased the TAC of BLC. G. urbanum extracts serve as redox-modulators and anti-inflammatory compounds, decreasing the intracellular level of “oncogenic” superoxide and cell proliferation.