Increased advanced glycation end products in atherosclerotic lesions of patients with end-stage renal disease.

Although advanced glycation end products (AGEs) are increased in the serum and tissues of patients with end-stage renal disease, little is known about the role of AGEs in atherogenesis. We therefore carried out an immunohistochemical study on the accumulation of AGEs and apolipoprotein B in the human aortas of diabetic and nondiabetic subjects with end-stage renal disease. The atherosclerotic lesions included diffuse intimal thickening, fatty streaks and atherosclerotic plaque. We used antibodies against two different epitopes of AGE structures, i.e. an Nepsilon-(carboxymethyl)lysine-protein adduct (CML) and a structure(s) other than CML (nonCML). The area that was positive for an antigen as a percentage of the total area (%Ar) was determined morphometrically, using an NIH-image program. In diffuse intimal thickening, atherosclerotic plaque and tunica media, the %Ar of CML and nonCML was significantly greater in diabetic or nondiabetic subjects with end-stage renal disease than in control subjects without end-stage renal disease. In fatty streaks, the %Ar of nonCML was significantly greater in nondiabetic subjects with end-stage renal disease than in control subjects, while no difference in the %Ar of CML was found between the subjects with or without end-stage renal disease. Nondiabetic subjects with end-stage renal disease showed a significantly increased %Ar of apolipoprotein B in fatty streaks and atherosclerotic plaque than the control subjects. The %Ar of CML and nonCML significantly correlated with the duration of hemodialysis in diffuse intimal thickening and atherosclerotic plaque of subjects with end-stage renal disease, but not in fatty streaks. On the other hand, the %Ar was not related to the duration of diabetes in any of the lesions in the diabetic subjects with end-stage renal disease. In diffuse intimal thickening and atherosclerotic plaque, subjects with end-stage renal disease showed a significant correlation between the %Ar of apolipoprotein B and AGEs (CML and nonCML), as well as their immunohistochemical colocalization. These results suggest that impaired AGE clearance may cause the increased accumulation of AGEs in the aortic wall of subjects with end-stage renal disease, thus resulting in the rapid progression of atherosclerosis. The accumulation of AGEs may be related to an enhanced LDL deposition in atherosclerotic lesions of subjects with end-stage renal disease.