P-3: Study of Relationship between Nitric Oxide and DNA Oxidative Marker in Semen of Diabetic Men

Background: The incidence of diabetes mellitus is rapidly increasing in the world. One of the complications of diabetes includes disturbance of the reproductive tract, such as infertility, erectile dysfunction, and endocrine disturbances. Nitric oxide (NO) is a free radical produced by most of cells including the human male and female reproductive tracts. NO has a dual role where low concentrations are essential for homeostatic cellular biology and physiology, but high levels have detrimental effects relating to cellular damage from this reactive oxygen species. 8-hydroxydeoxyguanosine (8-OHdG) is an oxidized nucleoside of DNA that has been currently used as a biomarker of cellular oxidative stress, where urinary levels have correlated with diabetic nephropathy and retinopathy. We aimed to investigate the relationship between NO levels and 8-OHdG levels in the semen of diabetic and non-diabetic men. Materials and Methods: Concentrations of NO and 8-OHdG were examined in seminal plasma of 32 diabetic and 35 non-diabetic men. NO level was assayed by colorimetric reaction and 8-OHdG was measured by ELISA methods. Results: Our results showed that the seminal plasma NO levels were significantly higher in diabetic group (p < 0.001). There were also significantly higher 8-OHdG levels in diabetic men compared to non-diabetic men (p < 0.001). Regression analysis indicated that in the diabetic men, NO levels correlated well with 8-OHdG levels (r=0.64, p<0.001). A significant trend between NO and sperm parameters was not observed. Conclusion: Our data suggests that high levels of NO in the semen of diabetic men, suggestive of reactive oxygen species induced DNA damage, correlated with 8-OHdG levels but not sperm parameters. These results support the further investigation of NO and 8-OHdG as biomarkers for assessing male infertility.