Decreased LDL Sialic Acid Levels in Insulin Dependent Diabetes Mellitus Patients with Nephropathy

Authors: Metin YILDIRIMKAYA, Kurtuluş YILMAZ, A. Necip YAVUZ, Ayhan KUBAR, N. Kemal NAZAROĞLU, Türker KUTLUAY

Abstract: LDL sialic acid content may determine its atherogenic capacity affecting its binding to arterial proteoglycans. Because diabetic nephropathy predicts the development of coronary heard disease (CHD), we investigated whethere LDL sialic acid content is affected in insulin dependent diabetes mellitus (lDDM) patients with microalbuminuria and clinical proteinuria. LDL sialic acid concentration and plasma glucose, creatinine, HbA1 lipid and lipoprotein levels were determined from fasting blood samples in 25 healthy subjects, 25 IDDM patients with a normal albumin excration rate, 25 patients with microalbuminuria and 25 patients with clinical proteinuria. The patient group were matched for age, sex, BMI, HbA1 levels and duration of diabetes. The control and patient groups had normal resting electrocardiograms and no major illness or acute inflammatory disease. LDL sialic acid concentration was found to be statistically lower p<0.001) in the microalbuminuric group (14.4+-2.3/mug/mg of protein) compared with the normal albuminuric patients (19.7+-3.1/mug/mg of protein) and healty subjects (19.9+-2.8/mug/mg of protein). Additionally, sialic acid level was also significantly lower (p<0.005) in the LDL of patients with clinical proteinuria (12.1+-3.0 /mug/mg of protein) than in the LDL sialic acid content was not correlated independently with age, BMI, duration of diabets, plasma glucose, creatinin, cholosterol, triglyceride or HbA_1 levels. These results suggest that desialylated LDL in the plasma of Patients with microalbuminuria or clinical proteinuria may be responsible in part for increased CHD risk observed in these patients.

Keywords: LDL Sialic, Diabetes mellitus nephropathy