Plasma levels of pentosidine in diabetic patients: an advanced glycation end product.

Nonenzymatic reactions between glucose and proteins yield advanced glycation end products (AGE) such as pentosidine. AGE accumulate in diabetic patients, alter the structure and function of tissue proteins, stimulate cellular response, and have thus been implicated in diabetic tissue damage. The present study was undertaken to assess the factors determining plasma total pentosidine level in diabetic patients and the possible relation between plasma pentosidine level and diabetic complications. In diabetic patients, including patients with renal failure, plasma pentosidine levels, assessed by HPLC assay, were correlated with serum creatinine (P < 0.0001). In patients with normal renal function, pentosidine levels were correlated with blood glucose control (hemoglobin Alc: P = 0.0028; fructoselysine: P = 0.0133), serum creatinine (P = 0.029), patient age (P = 0.0416), duration of diabetes (P = 0.0431), and total cholesterol (P = 0.0056) and LDL-cholesterol (P = 0.0208). Multiple regression analysis revealed an independent influence of hemoglobin Alc and serum creatinine on pentosidine levels (r2 = 0.216, P = 0.0026). Pentosidine levels were higher in patients with than in those without hypertension (P = 0.043) or ischemic heart diseases (P = 0.0061). No such differences were observed between patients with and without albuminuria or retinopathy. Multiple regression analysis revealed an independent influence of plasma pentosidine on the presence of hypertension (r2 = 0.129, P = 0.0382) and of plasma pentosidine and HDL-cholesterol on the presence of ischemic heart disease (r2 = 0.326, P = 0.0012). The present study demonstrated that plasma pentosidine level was significantly influenced by the quality of glycemic control and renal function. Pentosidine level was also correlated with hypertension and ischemic heart disease, and might be taken as a biomarker of diabetic cardiovascular risk.