Study of Capsaicin-induced Apoptosis in Human Colon Cancer Cell Lines

ABSTRACT

PURPOSE: Numerous investigations have been conducted in order to determine the potential carcinogenic or chemopreventive activity of capsaicin. The aim of this study is to characterize the effects of capsaicin on colon cancer cells, and provide valuable information concerning the application of capsaicin in chemoprevention as well as for therapeutic purposes. METHODS: CoLo320DM and LoVo cells (human colon cancer cell line) were treated with capsaicin. In order to access cell viability and altered morphology, an MTT assay was performed and the cells were microscopically examined. Decreasing DNA staining was accessed by FACS. The cells were stained with FITC labeled annexin V and analyzed by FACS to detect cellular membrane alteration during apoptosis. The cells were stained with DiOC6(3) and Hydroethidine and analyzed by FACS in order to access ROS and dleta psi m. RESULTS: Capsaicin decreased cell viability in a dose-dependent manner. Capsaicin produced a cell morphology corresponding to the apoptotic features including cell shrinkage and chromatic condensation. Capsaicin treated cells induced a loss of nuclear DNA leading to hypoploidy in a dose-dependent manner. Cells were excluded by double staining with PI and FITC labeled annexin v and detected by FACS. We show that treatment of CoLo320DM, L0Vo cells with increasing concentrations of capsaicin parallel an increase in the percentage of red fluorescent cells (HE-->Eth) that reflect ROS hypergeneration and a decrease in the percentage of green fluorescent cells that reflect delta psi m disruption. CONCLUSION: These results clearly demonstrate that capsaicin-induced colon cancer cell death is apoptotic.