This study aimed to determine the earliest markers of diabetic nephropathy (DN) onset with discriminative potentials from controlled diabetes (CD).Sixty male Wistar rats were allocated into three groups (20/group), the two diabetic groups CD and DN received 45 and 65 mg/kg STZ in 0.1 mole/L citrate buffer, respectively, while the control group received only the vehicle. Serum/urinary levels of glomerular, tubular, oxidative and proinflammatory markers were weekly monitored.Each diabetic group showed a different pattern of inflammatory, oxidative and signs of nephropathy along the study period, but none had a discriminative power until the fourth week. At this time point, levels of urinary transferrin, serum/urinary IL-6 and TNF-α as well as urinary IL-18 were significantly higher in DN group compared to CD (Urinary transferrin and the inflammatory endpoints proposed in this study might represent promising biomarkers for the early DN onset.