Influence of high glucose concentrations on the expression of glycosaminoglycans and N-deacetylase/N-sulphotransferase mRNA in cultured skin fibroblasts from diabetic patients with or without nephropathy.

Background: The Steno hypothesis postulates that a genetic defect in the regulation of the production of heparan sulphate by renal and non-renal cells determines susceptibility for the development of proteinuria and macro-angiopathy in patients with diabetic nephropathy (DN).

Methods: To test this hypothesis, skin fibroblasts isolated from type II diabetic patients with overt DN, micro-albuminuria, or without DN and from non-diabetic patients (n=8 for each group) were cultured in the presence of 5 or 25 mM D-glucose or in 25 mM L-glucose, and tested for the expression of N-deacetylase/N-sulphotransferase (NDST) 1 and 2 by semi-quantitative RT--PCR. Proteoglycan production was measured by means of metabolic labelling.