FGF23, NGAL, and Endostatin: the Predictors of Allograft Function in Renal Transplant Recipients

Objectives: Increased circulating levels of fibroblast growth factor 23, neutrophil gelatinase-associated lipocalin, and endostatin are independent risk factors for cardiovascular disease. Here, we evaluated correlations among these parameters and graft dysfunction and their relation with arterial stiffness. Materials and Methods: This prospective study included 73 maintenance kidney transplant patients with stable allograft function who had received the transplant at least 36 months previously. We calculated the estimated glomerular filtration rate (eGFR). Pulse-wave velocity was determined. Serum levels of fibroblast growth factor 23, neutrophil gelatinase-associated lipocalin, and endostatin were measured by enzyme-linked immunosorbent assay. Results: Demographic characteristics and pulse-wave velocity values were similar in groups 1 and 2 (GFR < 60 and > 60 mL/min, respectively). Mean levels of fibroblast growth factor 23 (P = .036), neutrophil gelatinase-associated lipocalin (P = .018), and endostatin were significantly higher in group 1. Fibroblast growth factor 23 was negatively correlated with eGFR (r = -0.267, P = .023) and positively correlated with neutrophil gelatinase-associated lipocalin (r = 0.258, P = .036) and endostatin (r = 0.321, P = .006). Serum endostatin levels were positively correlated with pulse-wave velocity (r = 0.276, P = .019). In linear regression analysis, eGFR was detected as the unique predictor of neutrophil gelatinase-associated lipocalin (P = .001). In addition, each 1 mL/min decrease in eGFR resulted in a 0.281 pg/mL increase in fibroblast growth factor 23 (P = .023) and a 0.04 ng/mL increase in neutrophil gelatinase-associated lipocalin (P = .007); each 1 cm/s increase in pulse-wave velocity resulted in a 3648.7 U/L increase of endostatin (P = .019). Conclusions: All 3 parameters were associated with loss of graft function in kidney transplant recipients. Moreover, endostatin can be used as an independent predictor for cardiovascular morbidity in this population.