Possible genetic defects in regulation of glycosaminoglycans in patients with diabetic nephropathy

• Published in: Diabetes (New York, N.Y.) Vol. 40; no. 6; pp. 764 - 770
• Main Authors: DECKERT, T, HOROWITZ, I. M, KOFOED-ENEVOLDSEN, A, KJELLEN, L, DECKERT, M, KYKKELUND, C, BURCHARTH, F
• Format: Journal Article
• Language: English
• Published: Alexandria, VA American Diabetes Association 01.06.1991
• Subjects: 550901 - Pathology- Tracer Techniques; Adult; AMINES; ANIMAL CELLS; Associated diseases and complications; BASIC BIOLOGICAL SCIENCES; BETA DECAY RADIOISOTOPES; BETA-MINUS DECAY RADIOISOTOPES; Biological and medical sciences; BIOSYNTHESIS; BODY; CARBOHYDRATES; Cells, Cultured; CONNECTIVE TISSUE CELLS; DAYS LIVING RADIOISOTOPES; DEUTERIUM; DIABETES MELLITUS; Diabetes Mellitus, Type 1 - genetics; Diabetes Mellitus, Type 1 - physiopathology; Diabetes. Impaired glucose tolerance; Diabetic Nephropathies - genetics; Diabetic Nephropathies - physiopathology; DISEASES; ENDOCRINE DISEASES; Endocrine pancreas. Apud cells (diseases); Endocrinopathies; EVEN-ODD NUCLEI; Female; FIBROBLASTS; Fibroblasts - metabolism; GLUCOSAMINE; Glucosamine - metabolism; Glycosaminoglycans - biosynthesis; Glycosaminoglycans - genetics; Glycosaminoglycans - isolation & purification; HEXOSAMINES; HEXOSES; Humans; HYDROGEN COMPOUNDS; HYDROGEN ISOTOPES; ISOTOPE APPLICATIONS; ISOTOPES; Kinetics; LIGHT NUCLEI; Male; Medical sciences; METABOLIC DISEASES; MONOSACCHARIDES; NUCLEI; ODD-ODD NUCLEI; ORGANIC COMPOUNDS; ORGANS; OXYGEN COMPOUNDS; PATHOGENESIS; PATIENTS; RADIOISOTOPES; Reference Values; SACCHARIDES; SKIN; Skin - metabolism; SOMATIC CELLS; STABLE ISOTOPES; SULFATES; Sulfates - metabolism; SULFUR 35; SULFUR COMPOUNDS; SULFUR ISOTOPES; Sulfur Radioisotopes; SYNTHESIS; TRACER TECHNIQUES; Tritium; TRITIUM COMPOUNDS; Endocrinopathy; Human; Cell culture; Regulation(control); Urinary system disease; Nephropathy; Pathogenesis; Insulin dependent diabetes; Complication; Glycosaminoglycan; Extracellular matrix; Fibroblast
• ISSN: 0012-1797; 1939-327X
• DOI: 10.2337/diab.40.6.764

The hypothesis of genetic defects in glycosaminoglycan (GAG) regulation among patients with insulin-dependent diabetes mellitus (IDDM) and nephropathy was assessed by studies in tissue cultures of fibroblasts obtained from 7 patients with normal urinary albumin excretion, 11 patients with diabetic nephropathy, and 6 nondiabetic control subjects. The incorporation of [2H] glucosamine and [35S] sulfate into hyaluronic acid (HA), chondroitin sulfate and dermatan sulfate (CS + DS), and heparan sulfate (HS) was measured in cells, matrix, and medium and related to micrograms of tissue protein. Large interindividual variations were seen in all three groups, and the incorporation of [3H] glucosamine into HA, CS + DS, and HS and [35S] sulfate into CS + DS and HS were not significantly different between the three groups. However, the fractional incorporation of [3H]glucosamine into HS was significantly reduced in diabetic patients with nephropathy compared with control subjects. This was the case not only when related to the total amount of GAGs (P = 0.014) but also when related to HA (P = 0.014). No significant difference was seen between control subjects and normoalbuminuric diabetic patients. The degree of N-sulfation of HS was not significantly different between the experimental groups. The results suggest that patients with diabetic nephropathy may suffer from deficiencies of coordinate regulation in the biosynthesis of GAG in fibroblasts, which may lead to a reduced density of HS in the extracellular matrix. If these changes reflect alterations in the biosynthesis of GAG from endothelial, myomedial, and mesangial cells, this observation may be relevant for the pathogenesis of severe diabetic complications.