Determination of NRF2 and GSTM1 Expression and Biomarkers of Oxidative Stress on Smoking and Nonsmoking Sperm: A Pilot study

Background and Aims: Smoking has an influence on different semen parameters. It is regarded as a risk factor for infertility. This study aims to evaluate the effect of smoking cigarettes on the expression of nuclear factor erythroid 2-related factor 2 (NRF2) and glutathione S-transferase Mu 1 (GSTM1) genes and biomarkers of oxidative stress in sperm. Materials and Methods: A case-control study was conducted on 15 men smoker (case) and 15 men nonsmokers (control) who had referred to infertility clinics in Isfahan, Iran. After sampling and analysis of semen quality parameters, gene expression of NRF2 and GSTM1 was determined using a Real time-polymerase chain reaction instrument. The lipid peroxidation and total antioxidant capacity (TAC) were evaluated by colorimetric methods. Results: Sperm concentration and their progressive motility in smokers were significantly lower than the nonsmoker population (p<0.001). In addition, the lipid peroxidation level increased and TAC level (p<0.01) as well as gene expression of NRF2 (p<0.05) and GSTM1 (p<0.01) decreased compared to control groups. Conclusions: Our data demonstrated that the NRF2 and GSMT1 expressions are significantly lower in human males with low sperm motility and correlated with specific sperm quality parameters.