Advanced glycation end products derived from serum albumin modification by glucose (AGE-1) reflect clustering of lipid-associated metabolic abnormalities and are decreased in patients treated with acarbose: A cross-sectional study

Background. Advanced glycation end products (AGEs) are formed during protein modification by a reduction of sugars or reactive aldehydes. Depending on the pathology, various AGEs may be formed. They are stable compounds and are considered as potential diseases markers. Objectives. The objective of this study was to assess glucose-mediated albumin modification that yields non-standard epitopes of AGEs (AGE-1) in diabetes and in associated metabolic abnormalities. Material and methods. The AGE-1, expressed as median AGE-1 level and AGE-1 positivity, was determined in 246 individuals (198 with prediabetes/diabetes) using a new slot-dot-blot method (allowing for detection of barely traceable analytes) and related to the presence of diabetes-associated metabolic abnormalities and complications, and treatment. Results. The AGE-1 level was higher in patients with prediabetes/diabetes than in controls. Its elevation was associated with metabolic syndrome (MetS), obesity, hyperlipidemia, and non-alcoholic fatty liver disease (NAFLD) but not with diabetic control or micro- and macroangiopathy, except for atherosclerotic plaques formation in carotid arteries. The AGE-1-positive patients had higher triglycerides and lower high-density lipoprotein (HDL)-cholesterol. In patients untreated with aspirin, AGE-1 positivity was associated with higher C-reactive protein (CRP) level. Treatment with aspirin, sulfonylureas and gliptins was associated with higher AGE-1 level and with dyslipidemia medications with higher AGE-1 positivity. In patients with abnormal glucose metabolism, acarbose treatment was associated with lower AGE-1 positivity. Multivariate analysis showed MetS, carotid artery plaques, NAFLD, and treatment with aspirin and acarbose to be independently associated with AGE-1 positivity. Conclusions. Unlike standard AGEs, AGE-1 is more tightly associated with abnormalities in lipid than glucose metabolism, and lower in patients treated with acarbose but not with other antidiabetics.