Alterations in the rat renal glycosaminoglycans in streptozotocin-induced diabetes

The effect of streptozotocin-induced diabetes on the glycosaminoglycan composition of rat renal cortical tissue was evaluated. Glycosaminoglycans were isolated and purified from the kidney cortex of control and diabetic rats by means of digestion with collagenase, pronase and ethanol precipitation. Subsequent fractionation was performed by ion exchange chromatography on Dowex 1-X2 Cl using various concentrations of sodium chloride solution. The glycosaminoglycan in each fraction was characterized by digestion with hyaluronidase, chondroitinase AC and ABC. The undigested glycosaminoglycans were separated after each enzyme digestion and quantitated. The glycosaminoglycan composition of each fraction was computed from the enzyme digestion profile. The results indicate that in renal cortex of streptozotocin induced diabetic rats there was a significant reduction in the levels of dermatan sulfate, heparan sulfate and hyaluronic acid, while the chondroitin sulfate remained unaffected. In light of this finding, the significance of these anionic polysaccharides in renal functions is discussed.