The effects of resveratrol and tannic acid on apoptosis in colon adenocarcinoma cell line.

OBJECTIVE To investigate the effects of resveratrol and tannic acid on apoptosis, and Bcl-2 homologous antagonist/killer (Bak) and fas associated death domain (FADD) proteins in the CaCo-2 cell line. METHODS In the present study, resveratrol and tannic acid were administrated in the CaCo-2 cell line at doses of 25, 50, and 100 microM. The CaCo-2 cells were grown and cultured in the Medical Biology Department, Eskisehir Osmangazi University, Eskisehir, Turkey in 2007. The effects of these agents on apoptotic index were determined by Apop Taq peroxidase kit and their effects on the ratios of Bak and FADD proteins by the immunohistochemical staining method at 24, 48, and 72 hours. Stained and non-stained cells in 30 separate areas of the 3 separate chamber slides, prepared for each group, were counted. The percentage of apoptosis, and Bak and FADD proteins was calculated with the control. Mean +/- standard error values were calculated for the 3 experiments. RESULTS Apoptotic index, Bak protein percentage ratio, and FADD protein percentage ratio values in all groups that received tannic acid and resveratrol increased when compared within the groups. This increase was found to be time and dose independent in all parameters. CONCLUSION Cells undergo apoptosis in 2 pathways (mitochondrial and death receptor) in resveratrol and tannic acid induced CaCo-2 cells.