Curcumin-Induced DNA Damage and Inhibited DNA Repair Genes Expressions in Mouse-Rat Hybrid Retina Ganglion Cells (N18)

Abstract

Curcumin is reported to be a potent inhibitor of the initiation and promotion of many cancer cells. We investigated to examine whether or not curcumin induce DNA damage in mouse-rat hybrid retina ganglion cell line N18 cells. The Comet assay showed that incubation of N18 cells with 10, 25 and 30 mu M of curcumin led to a longer DNA migration smear (Comet tail). The DNA gel electrophoresis showed that 20 mu M of curcumin for 24 and 48 h treatment induced DNA damage and fragments in N18 cells. The real time PCR analysis showed that 20 mu M of curcumin for 48 h treatment decreased ATM, ATR, BRCA1, 14-3-3 sigma, DNA-PK and MGMT mRNA, and ATM and MGMT mRNA expression were inhibited in a time-dependent manner. Our results indicate that curcumin caused DNA damage and inhibited DNA repair genes which may be the factors for curcumin-inhibited cell growth.