Nicotine effects on enzymatic antioxidant defenses in human breast and ovarian cell lines

Nowadays, the prevalence of nicotine abuse among women has increased dramatically. In the current study, we aimed to investigate the effect of nicotine exposure on breast MCF-7 and ovarian OVCAR-3 cell lines for assessing the toxicity of nicotine in the cells of these organs.

The MCF-7 and OVCAR-3 cells were treated with increasing nicotine concentrations ranging from 0 (control), 10-11, 10-8 and 10-6 M for 24h. Effect of nicotine treatments on major antioxidant enzymes catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), cellular levels of glutathione (GSH) and malondialdehyde (MDA) were monitored.

We showed that the CAT activity in MCF-7 cells increased only at 10-6 M dose of nicotine. The GPx and GR activity was decreased at 10-8 and 10-6 M of nicotine in MCF-7 cells, but in OVCAR-3 cells, this decrease was significant only at 10-6 M dose of nicotine. Reduced GSH decrease was statistically significant only at 10-8 and 10-6 M of nicotine in MCF-7 cells; otherwise, in OVCAR-3 cells, this decline was significant only at 10-6 M of nicotine. Nicotine at 10-8 and 10-6 M concentration caused a significant increase in MDA levels in MCF-7 cells.

This study showed that breast MCF-7 cells are more vulnerable than ovarian OVCAR-3 cells against nicotine-induced oxidative toxicity.