Fig. 3

Characterization of antioxidant response time course in the presence of leptin (10, 100 ng/ml) in human mammary epithelial cells. a: Antioxidant response of HMEC. b: Antioxidant response of MCF-7. c: Antioxidant response of MDA-MB-231. In terms of: 1- Heme oxygenase 1 mRNA expression, 2- Heme oxygenase 1 catalytic activity, 3- Glutathione peroxidase 1 mRNA expression, 4- Glutathione peroxidase 1 catalytic activity, 5- Glutathione S-transferase catalytic activity. Values are expressed as mean ± standard deviation (n = 6). Between-groups comparison was performed by one-way ANOVA followed by the Kruskal-Wallis multiple comparison test. The significance level was set at 0.05. Statistical significance between groups is indicated by * p < 0.05, ** p < 0.01 and *** p < 0.001