Immunohistochemical detection of imidazolone, a novel advanced glycation end product, in kidneys and aortas of diabetic patients.

Abstract

To investigate the role of the Maillard reaction in the pathogenesis of diabetic complications, we produced several clones of monoclonal antibodies against advanced glycation end products (AGEs) by immunizing mice with AGE-modified keyhole limpet hemocyanin, and found that one clone (AG-1) of the anti-AGE antibodies reacted specifically with imidazolones A and B, novel AGEs. Thus, the imidazolones, which are the reaction products of the guanidino group of arginine with 3-deoxyglucosone (3-DG), a reactive intermediate of the Maillard reaction, were found to be common epitopes of AGE-modified proteins produced in vitro. We determined the erythrocyte levels of imidazolone in diabetic patients using ELISA with the monoclonal anti-imidazolone antibody. The imidazolone levels in the erythrocytes of diabetic patients were found to be significantly increased as compared with those of healthy subjects. Then we studied the localization of imidazolone in the kidneys and aortas obtained from diabetic patients by immunohistochemistry using the antibody. Specific imidazolone immunoreactivity was detected in nodular lesions and expanded mesangial matrix of glomeruli, and renal arteries in an advanced stage of diabetic nephropathy, as well as in atherosclerotic lesions of aortas. This study first demonstrates the localization of imidazolone in the characteristic lesions of diabetic nephropathy and atherosclerosis. These results, taken together with a recent demonstration of increased serum 3-DG levels in diabetes, strongly suggest that imidazolone produced by 3-DG may contribute to the progression of long-term diabetic complications such as nephropathy and atherosclerosis. ( J. Clin. Invest. 1997. 99:1272-1280.)

Renal accumulation and clearance of advanced glycation end-products in type 2 diabetic nephropathy: effect of angiotensin-converting enzyme and vasopeptidase inhibition

“…ZDF rats showed a hyperglycaemia-induced increase in renal CML, pentosidine and 3-DG-imidazolone, indicating broad-spectrum effects on the chemistry and detoxification of reactive carbonyl compounds in diabetes. Elevated renal accumulation of CML, pentosidine and 3-DG-imidazolone in diabetes and diabetic nephropathy has also been reported in other studies [24,25]. However, this is the first time that an increase in all three AGE subtypes has been demonstrated in ZDF rats, an increase that was suppressed simultaneously by drug intervention.…”

Diabetic retinopathy risk correlates with intracellular concentrations of the glycoxidation product N e -(carboxymethyl) lysine independently of glycohaemoglobin concentrations

“…AU, arbitrary units cells to hyperglycaemia. 3-DG-derived AGEs are also found in a variety of diabetic tissues [15] and increase in diabetic erythrocytes 1.8-fold over normal.…”

“…One ml of lymphocyte lysate solution was loaded onto nitrocellulose membranes (Schleicher & Schüll, Dassel, Germany). Membranes were dried for 10 min at room temperature and subsequently blocked with 5 % nonfat dry milk in PBS-T (0.5 % tween 20 in PBS, pH 7.4) for 1 h. After repeated washings (PBS-Tween 1 15 min, 2 5 min), they were incubated using the following antibodies: a polyclonal anti-CML antibody (diluted 1 : 10 000) [14], a monoclonal anti-methylglyoxal-derived AGE antibody (1 mg/ml) [10] and a monoclonal antibody directed against a 3-DG-derived AGE epitope (1 mg/ml) [15].…”

FEEL-1 and FEEL-2 Are Endocytic Receptors for Advanced Glycation End Products

“…These proinflammatory responses are implicated to contribute to the development of pathologies associated with aging, diabetes mellitus, and Alzheimer's disease (6). Indeed, AGEs were shown to be present in atherosclerotic lesions (7) and diabetic kidney (8).…”