GUANIDINOACETIC ACID(GAA) IN PATIENTS WITH CHRONIC KIDNEY DISEASE(CKD) AND DIABETES MELLITUS(DM)

Abstract

GAA is the precursor of creatine, an essential in the energy metabolism of muscle and nerve tissue. GAA is mainly produced in the kidney. GAA production was reported to be suppressed in the streptozotocin-induced DM rats. However, GAA metabolism has not been really investigated in CKD or DM patients. In this study, we determined serum level(S) and urinary excretion(U) of GAA and creatinine(Cr) in patients with chronic glomerulonephritis (CGN) and DM. The subjects were 15 healthy adults, 92 patients with CGN and 27 patients with non insulin-dependent DM nephropathy. S and U-GAA were determined with HPLC. As shown in the Table describing mean values, U-GAA of early stage CKD patients was significantly lower than healthy subject. And S-GAA decreased with loss of renal function or with U-Cr, especially in DM patients. N S-Cr U-Cr S-GAA U-GAA (mg/dL) (mg/day) (μg/dL) (mg/day) Normal 15 0.9 1633 38.2 103.0 CGN(Ccr>90mL/min) 12 1 1742 41.1 41.3⁎ CGN(Ccr60mL/min) 16 0.9 775⁎ 27.8⁎ 46.2⁎ DM(Ccr<60mL/min) 11 5.0⁎ 581⁎ 22.1⁎ 2.3⁎ In conclusion, GAA production in the kidney decreased in CKD patients, suggesting GAA deficiency was a reason of muscle wasting of CKD and DM patients.