SIRT1 and Infertility: Keeping in mind the limited antioxidant activity in seminal plasma, we aimed to conduct the present study to (i) understand the roles of SIRT1 and SIRT3 proteins in regulating levels of DNA damage and telomere length in infertile and fertile men, (ii) determine whether leukocyte telomere length (LTL) is correlated with sperm telomere length (STL) and its prognostic potential for male infertility, and (iii) investigate whether oxidative biomarkers are correlated with semen parameters in infertile men.