Background: The present study was designed to explore whether serum stromal cell-derived factor-1 (SDF-1) levels were associated with albuminuria, estimated glomerular filtration rate (eGFR) and diabetic kidney disease (DKD), and detect which clinical parameters might affect serum SDF-1 levels in patients with type 2 diabetes (T2D).
Methods: Serum SDF-1 levels were measured by sandwich ELISA. Patients with an eGFR < 60ml/min/1.73m2 and/or a urinary albumin-to-creatinine ratio (UACR) ≥ 30mg/g who presented with diabetic retinopathy were identified as having DKD.
Results: Serum SDF-1 levels in T2D patients were significantly higher than those in healthy controls (p < 0.05). Urinary albumin and UACR were positively correlated with serum SDF-1 levels (r = 0.216 and = 0.276, respectively, p < 0.01), and eGFR was inversely related with serum SDF-1 levels (r = -0.368, p < 0.001). Moreover, after adjusting for other clinical covariates by multiple linear regression analyses, the serum SDF-1 levels were independently associated with urinary albumin (β = 0.071, t = 2.185, p < 0.05), UACR (β = 0.071, t = 2.077, p < 0.05) and eGFR (β = -3.975, t = -3.375, p < 0.01). Furthermore, receiver operating characteristic analysis indicated that the optimal SDF-1 cutoff value for predicting macroalbuminuria was 5.735 ng/mL (its corresponding sensitivity was 50.00% and specificity was 81.46%), for predicting abnormal albuminuria was 4.321 ng/mL (its corresponding sensitivity was 58.46% and specificity was 70.78%) and for predicting DKD was 3.505 ng/mL (its corresponding sensitivity was 83.33% and specificity was 42.86%).
Conclusions: The serum SDF-1 levels were positively associated with urinary albumin, UACR and cystatin C, and negatively associated with eGFR, which indicate that SDF-1 may play a critical role in the onset and progression of DKD.