The cytotoxic activity of
curcumin towards CCRF-CEM human
T-cell leukemia cells was measured by the MTT assay.
Tumor cells were more sensitive to the cytotoxic activity of
curcumin or
curcumin-Cu (II)compared to normal cells, and the IC(50) of
curcumin towards CCRF-CEM cells was 8.68 microM, and that of
curcumin-Cu (II) was 8.14 microM. The cell cycle distribution of
curcumin-treated CCRF-CEM cells was analyzed by flow cytometry. DNA damage induced by
oxidants such as
curcumin-Cu (II)
ions is considered as one of the main causes of cell inactivation. Therefore, we analyzed the effect of
curcumin on DNA damage by
agarose gel electrophoresis and atomic force microscopy (AFM). Gel electrophoresis analyses showed that
curcumin or Cu (II) alone failed to cause DNA damage in pBR322 plasmid
DNA as compared with the normal plasmid. However,
DNA plasmids were mostly damaged
after treatment with
curcumin of different concentrations in the presence of Cu (II). Two forms were observed by means of AFM: closed circular plasmids and linear plasmids. DNA damage induced by a combination of
curcumin and Cu (II) was also found by
agarose gel electrophoresis, which was applied as control method to verify the results obtained by AFM.