Comparison of 8-hydroxy-2'-deoxyguanosine (8-OHdG) levels using mass spectrometer and urine albumin creatinine ratio as a predictor of development of diabetic nephropathy.
BACKGROUND
Measurement of urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG) has recently become more popular as a means of assessing oxidative stress in the human body. The aim of this study is to compare the levels of urine 8-OHdG in patients with type 2 diabetes with and without nephropathy and to evaluate its role as a biochemical marker for distinguishing these patients from healthy and patients without complications.


METHODS
For this purpose, 52 patients with type 2 diabetes mellitus (32 with nephropathy (DMN), 20 without nephropathy (DM)) and 20 healthy control subjects (C) were included in this study. The urine concentrations of 8-OHdG were measured by modified LC-MS/MS method and compared with the first morning voiding urine albumin/creatinine ratio (UACR) and HbA1c values of the same patients.


RESULTS
The concentrations of urine 8-OHdG in DMN and DM patients were higher than those of the control subjects (3.47 ± 0.94, 2.92 ± 1.73, 2.1 ± 0.93 nmol/mol creatinine, respectively). But there was no statistical difference between DMN and DM (p = 0.115). There is significant correlation between urinary 8-OHdG and UACR (r = 0.501, p < 0.001). According to ROC analysis, the AUC value of HbA1c was higher than the value of the AUC of 8-OHdG (0.882 and 0.771, respectively).


CONCLUSIONS
This study shows that the urine 8-OHdG levels increase in diabetic patients. However, urinary 8-OHdG is not a useful clinical marker, compared with UACR, to predict the development of diabetic nephropathy in diabetic patients.
Gulhane School of Medicine, Department of Clinical Chemistry, Etlik, Ankara, Turkey. maserdar@gata.edu.tr
Muhittin
M
Serdar
Erdim
E
Sertoglu
Metin
M
Uyanik
Serkan
S
Tapan
Kadir
K
Akin
Cumhur
C
Bilgi
Ismail
I
Kurt
D000080242:8-Hydroxy-2'-Deoxyguanosine; D000419:Albuminuria / Q000652:urine*; D015415:Biomarkers / Q000652:urine; D016022:Case-Control Studies; D003404:Creatinine / Q000652:urine*; D003849:Deoxyguanosine / Q000031:analogs & derivatives* / Q000652:urine; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000652:urine*; D003928:Diabetic Nephropathies / Q000652:urine*; D005260:Female; D006442:Glycated Hemoglobin / Q000378:metabolism; D006801:Humans; D008297:Male; D013058:Mass Spectrometry; D008875:Middle Aged; D017382:Reactive Oxygen Species; D053719:Tandem Mass Spectrometry / Q000379:methods
D000080242:8-Hydroxy-2'-Deoxyguanosine; D015415:Biomarkers; D003404:Creatinine; D003849:Deoxyguanosine; D006442:Glycated Hemoglobin; D017382:Reactive Oxygen Species; C517652:hemoglobin A1c protein, human