Guaraná a richest caffeine food increase oxaliplatin sensitivity of colorectal HT-29 cells by apoptosis pathway modulation.
Anticancer Agents Med Chem. 2015 Dec 17. Epub 2015 Dec 17. PMID: 26673759
Francine Carla Cadoná
We investigated the in vitro effects of guaraná and its main metabolites (caffeine, theobromine and catechin) on cytotoxicity and cell proliferation on colorectal cancer (CRC) line HT-29 cells and on oxaliplatin sensitivity. The cells were exposed to different concentrations of guaraná extract with and without oxaliplatin. The concentrationsof bioactive molecules were also estimated considering their potential proportion on guaraná hydro-alcoholic extract. Apoptosis effect was analyzed by annexin V quantification using flow cytometry, while apoptosis pathway gene modulation (p53, Bax/Bcl-2 genes ratio, caspases 8 and 3) was determinedby qRT-PCR analysis. Cells exposed to guaraná at a concentration of 100 μg/mL presented a similar cytotoxic effect as HT-29 cells treated with oxaliplatin and did not affect the sensitivity of the drug. Guaraná presented cell antiproliferative effect and increased anti-proliferative oxaliplatinsensitivity at all concentrations tested here. Guaraná was able to induce apoptosis and up-regulate the p53 and Bax/Bcl-2 genes.