Evaluation of gender-related differences in response to oxidative stress in toxoplasma gondii positive serum

Purpose: Toxoplasma gondii (T. gondii) is the causative agent of toxoplasmosis. It infects up to one third of the human population. The aim of this study was to evaluate the effects of T. gondii infection on induction of oxidative stress in serum of infected men and women. Materials and Methods: This case-control study was carried out on 150 individuals who had referred to our center in Tehran. Serum was obtained from venous blood samples. Immunoglobulin G (IgG) anti-toxoplasma antibody enzyme linked immunosorbent assay (ELISA) test was performed on all of the samples. Those who were IgG positive were regarded as the case group (52 women and 23 men) and the others as the control group (43 women and 32 men). The data were analyzed by INSTAT software using ANOVA followed by Tukey. Results: Serum superoxide dismutase activity in men of the case group was significantly higher than in the control group (7.81 ± 0.38 vs. 6.69 ± 0.17, P = .045). Catalase activity in men of the case group was significantly higher than the control group (8.64 ± 0.55 vs. 6.23 ± 0.38,P = .006). Glutathione S-transferase activity and malondialdehyde level in women of the case group were significantly higher than the control group (5.98 ± 0.24 vs. 4.73 ± 0.28, P = .037 and 2.3 ± 0.09 vs. 1.9 ± 0.09, P = .032, respectively). Catalase activity and glutathione level in women of the case group were lower than the control group (6.0 ± 0.45 vs. 7.63 ± 0.48, P = .043 and 0.62 ± 0.05 vs. 0.89 ± 0.05, P = .007, respectively). Conclusion: T. gondii infection induces oxidative stress in women’s serum because of the decreased catalase activity, glutathione depletion and increasing lipid peroxidation. The increased antioxidant enzyme activities in infected men were because of the adaptive response to the generated free radicals. Women were found to be more sensitive to the effects of toxoplasma infection on oxidative stress induction compared to men.