Effect of fluoride on molecular weight, charge density and age related changes in the sulphated isomers of glycosaminoglycans of the rabbit cancellous bone.

The effect of fluoride on the composition, molecular weight and charge density of the glycosaminoglycan isomers in the cancellous bone of the iliac crest region of the pelvic girdle was studied in rabbits treated with fluoride for 3, 9 and 16 months and the corresponding age-matched controls. With advancing age the chondroitin-6-sulphate concentration was found to increase in the fluoride-treated as well as the control animals. The concentration of dermatan sulphate was found to decrease with advancing age in the control groups. However, the fluoride-treated groups showed increasing concentrations of dermatan sulphate as the age and the duration of fluoride treatment advanced. The glycosaminoglycans in the fluoride-treated group showed the presence of low-molecular-weight molecules which were not found in the corresponding control group, and also showed an increased charge-density heterogeneity as compared to the corresponding control group. The data presented provide evidence to suggest that glycosaminoglycans of cancellous bone undergo age-related changes in their isomeric profile. The increase in dermatan sulphate and the presence of low-molecular-weight, highly charged molecules in the adult fluorosed bone may be related to the cartilagenous loci formation as reported earlier.