Endocrine Abstracts

Aim: The aim of this study was to investigate the relationship between the clinical and laboratory findings of metabolic bone disease regarding the levels of osteoprotegerin (OPG) and the receptor activator of nuclear factor kappa B ligand (RANKL) in the patients with diabetic nephropathy.

Material and method: This study includes 61 type 2 diabetic patients and age-, sex-matched 20 healthy subjects. Diabetic patients were divided into three groups according to a modification of Mogensen’s clinical classification (stage III, stage IV, stage V). In addition, diabetic patients were further divided into two groups according to glomerular filtration rate (GFR) as follows: group 1: GFR<60 ml/min per 1.73 m², group 2: GFR>60 ml/min per 1.73 m². The serum OPG and RANKL levels were determined by ELISA according to manufacturer’s manual.

Results: The serum iPTH, P and RANKL level in diabetic patients was found significantly higher than in control group (P<0.05). There were no significant differences in the serum OPG levels and RANKL/OPG ratio among the groups. No significant differences were determined between levels of OPG, RANKL, and RANKL/OPG ratio in diabetic nephropathy stages. The serum RANKL levels were significantly higher in the group 1 diabetics than in the group 2 diabetic patients (P<0.05), whereas there were no significant differences in serum OPG level and RANKL/OPG ratio between the group 1 and group 2 diabetics. In addition, RANKL levels and RANKL/OPG ratio were found to be correlated positively with ALP levels in group 1 diabetic patients (P< 0.05).

Conclusion: Our results suggest that increased serum RANKL levels might play role in development of the metabolic bone disease in patients with diabetic nephropathy.