Acute modulation of albumin microvascular leakage by advanced glycation end products in microcirculation of diabetic rats in vivo

• Published in: Diabetes (New York, N.Y.) Vol. 48; no. 10; pp. 2052 - 2058
• Main Authors: BONNARDEL-PHU, E, WAUTIER, J.-L, SCHMIDT, A. M, AVILA, C, VICAUT, E
• Format: Journal Article
• Language: English
• Published: Alexandria, VA American Diabetes Association 01.10.1999
• Subjects: Age; Albumins - metabolism; Animals; Anticholesteremic Agents - pharmacology; Associated diseases and complications; Biological and medical sciences; Blood Glucose - metabolism; Blood vessels; Capillary Leak Syndrome - complications; Capillary Leak Syndrome - metabolism; Development and progression; Diabetes; Diabetes mellitus; Diabetes Mellitus, Experimental - complications; Diabetes Mellitus, Experimental - metabolism; Diabetes. Impaired glucose tolerance; Endocrine pancreas. Apud cells (diseases); Endocrinopathies; Glycation End Products, Advanced - metabolism; Glycosylation; Male; Medical sciences; Microcirculation; Microcirculation disorders; Permeability; Physiological aspects; Probucol - pharmacology; Rats; Rats, Wistar; Reactive Oxygen Species - metabolism; Receptor for Advanced Glycation End Products; Receptors, Immunologic - immunology; Receptors, Immunologic - metabolism; Recombinant Proteins - metabolism; United States; Endocrinopathy; Rat; Diabetes mellitus; Reaction product; Rodentia; Permeability; Glycation; Microcirculation; Vertebrata; Mammalia; Extravasation; Blood vessel; Complication; Circulatory system
• ISSN: 0012-1797; 1939-327X
• DOI: 10.2337/diabetes.48.10.2052

Acute modulation of albumin microvascular leakage by advanced glycation end products in microcirculation of diabetic rats in vivo. E Bonnardel-Phu , J L Wautier , A M Schmidt , C Avila and E Vicaut Department of Biophysics, F. Widal Hospital, Paris, France. Abstract Advanced glycation end products (AGEs) are nonenzymatic glycosylated adducts of proteins that accumulate in vascular tissue during diabetes and aging. The aim of this work was to study the role of AGEs and of the oxidative mechanisms in diabetes-induced changes in vascular permeability. Intravital videomicroscopy was used to study albumin microvascular leakage in cremaster muscle. The extravasation of a fluorescent macromolecular tracer (fluorescein isothiocyanate-albumin) was measured for 1 h and, after computer-aided image analysis, was expressed as variations of normalized gray levels (arbitrary units). Extravasation of the macromolecular tracer was much higher in diabetic rats than in control rats (slope of extravasation versus time increased by >100%, P < 10(-4)). This increase was significantly inhibited when we blocked AGEs binding to their endothelial receptor by intravenous bolus of soluble recombinant receptor to AGEs (rR-RAGE) (slope of extravasation versus time decreased by 19, 30, and 40%, for 0.5, 2.5, and 5.15 mg/kg rR-RAGE, respectively) or by a 6 mg/kg intravenous bolus of antibody against RAGE (slope decreased by 53%). Systemic injection of probucol (an antioxidant) also significantly inhibited the increase in the extravasation of the macromolecular tracer occurring in experimental diabetes (slope decreased by 51%, P < 10(-4)). These results strongly suggest that in experimental diabetes the interaction of circulating AGEs and endothelial RAGE mediates albumin micro-vascular leakage, possibly via AGE-RAGE-dependent enhanced oxidant stress.