Effect of chondroitin sulfate on the type I collagen metabolism in the compact bone in alloxan-induced rats

Abstract

Aim. To study the type I collagen metabolism in the compact bone in rats with alloxan-induced diabetes receiving sulfated glycosaminoglycans. Methods. The study was performed on 67 white outbred male rats with body weight of 180-220 g. Mortality at diabetes reproduction was 44.8%. To clarify the role of exogenous glycosaminoglycans on bone collagen metabolism at diabetes mellitus, 16 animals with alloxan-induced diabetes received 1 mg/kg of chondroitin sulfate intramuscularly every second day. The second group (21 animals) with alloxan-induced diabetes did not received any chondroitin sulfate. Control group included 10 intact animals who were administered a single injection on 0.5% ml of normal saline. The levels of type I collagen metabolism markers (PINP - aminoterminal propeptide of type I procollagen, a marker of bone formation; β-CrossLaps - β-isomerized carboxy-terminal cross-linking region of type I collagen, a marker of bone resorption) and the amount of total collagen were determined in homogenates of femoral shaft. Results. Administration of alloxan to the animals has induced the development of diabetes mellitus. The levels of PINP and β-CrossLaps was significantly higher in alloxan-induced rats which were administered chondroitin sulfate compared to rats with «isolated» alloxan-induced diabetes by 21 (p=0.001) and 28 (p=0.01) days of follow-up, the level of total collagen was higher at 70% at 28 day of the experiment (p=0.0004). Conclusion. Effect of sulfated glycosaminoglycans on type I collagen metabolism of the compact bone in animals with «isolated» alloxan-induced diabetes is manifested by intensified catabolic and anabolic processes with a predominance of the latter over the control and alloxan-induced rats at 21 and 28 days of the experiment.