Association between sirtuin 1 and markers of oxidative stress in master athletes

Abstract Background Lifelong training in master athletes confers protective effects, promoting higher sirtuin levels and enhanced antioxidant capacity. Although Sirtuin 1 (SIRT1) is well studied, no previous study has examined the relationship between circulating SIRT1 levels and antioxidant defense variables in master athletes. Purpose To compare and analyze the relationships between circulating levels of SIRT1 and variables related to antioxidant defense in master athletes (MA) and untrained middle-aged individuals (UMA). Methods Male MA ( n = 42; 51.62 ± 7.33 years; ≥10 years of training and competition in running) and UMA ( n = 15; 47.73 ± 8.52 years) were evaluated. Venous blood samples were collected for biochemical analyses of SIRT1, antioxidant enzymes, TBARS and F2-isoprostanes, 8-OHdG, and redox balance indexes. Results MA showed higher levels of SIRT1 (18.22 ± 4.53 vs. 6.08 ± 2.11 ng/mL; p < 0.0001), as well as of SOD, CAT, and GSH ( p < 0.001), indicating a more favorable antioxidant profile. After adjustment for body fat percentage, differences in SOD, CAT, GSH and TBARS, remained significant. SIRT1 was positively correlated with SOD ( r = 0.279; p = 0.031), CAT ( r = 0.485; p < 0.001), GSH ( r = 0.476; p < 0.001) and CAT/8-OHdG ( r = 0.430; p = 0.032), and negatively correlated with TBARS ( r = − 0.518; p < 0.001). Conclusion Master athletes exhibited higher circulating SIRT1 concentrations and a more favorable systemic redox profile than untrained individuals, with SIRT1 being associated with markers of antioxidant defense, lipid peroxidation, and redox balance.