Significance of 8-hydroxy-2'-deoxyguanosine levels in patients with chronic renal failure

SUMMARY:     The aim of this study was to determine the significance of 8-hydroxy-2'-deoxyguanosine (8-OHdG), which is known as a marker of oxidative stress in vivo , in patients with chronic renal failure (CRF). Fifty-one non-dialysed CRF patients (29 men and 22 women; mean ± SD age, 57.8 ± 12.8 years) who were under dietary therapy for at least 6 months were enrolled in the study. Both serum and urinary 8-OHdG levels were measured by using high-sensitive enzyme-linked immunosorbent assay (ELISA) kits. We examined the relationship between 8-OHdG levels and clinical indices in patients with CRF. As a result, the serum 8-OHdG level was strongly correlated with serum levels of urea nitrogen (UN; r  = 0.58; P  < 0.0001), creatinine (Cr; r  = 0.53; P  < 0.0001), and β2-microglobulin (β2-MG; r  = 0.54; P  < 0.0001). Furthermore, the serum 8-OHdG level was inversely correlated with creatinine clearance (Ccr; r  = −0.54; P  < 0.0001). In contrast, urinary 8-OHdG level was not correlated with any of the clinical parameters. This is the first report of 8-OHdG level determination in patients with CRF. It is suggested that serum 8-OHdG level is not sufficient as a marker of oxidative damage in patients with CRF, and it should be corrected according to the residual renal function to estimate the accurate degree of oxidative stress.