chondroitin-sulfates and Fluorosis--Dental

Proteoglycans (PGs) were isolated from the dentin-predentin of fluorotic and control rat incisor teeth using demineralization in EDTA, followed by extraction with 4 M guanidinium chloride in the presence of protease inhibitors. Differences in the behaviour of fluorotic and control PG were evident during purification by anion exchange chromatography on Q-Sepharose and MONO-Q interfaced with fast protein liquid chromatography. The PG from fluorotic teeth exhibited a more anionic profile, due to changes in glycosaminoglycan characteristics, since no apparent differences were evident between the respective core proteins, both of which were 45 kDa. The constituent glycosaminoglycan chains of fluorotic dentin were of lower molecular size and showed the additional presence of dermatan sulfate and heparan sulfate by comparison to nonfluorotic controls, where only chondroitin-4-sulfate was detected.

Topics: Animals; Anions; Chondroitin Sulfates; Chromatography, Agarose; Chromatography, Ion Exchange; Chromatography, Liquid; Decalcification Technique; Dentin; Dermatan Sulfate; Edetic Acid; Fluorosis, Dental; Glycosaminoglycans; Guanidine; Guanidines; Heparitin Sulfate; Incisor; Male; Molecular Conformation; Molecular Weight; Protease Inhibitors; Protein Denaturation; Proteoglycans; Rats; Rats, Wistar

Fluorosed human teeth have lower concentrations of glycosaminoglycan (GAG) disaccharides and an increased dermatan sulphate content. Teeth from subjects with a high fluoride intake have a higher ratio of 4-sulphated to 6-sulphated GAGs. Increased dermatan sulphate may be an important factor in the clinical manifestations of fluorosis.

Topics: Adolescent; Adult; Child; Chondroitin Sulfates; Dermatan Sulfate; Fluorosis, Dental; Glycosaminoglycans; Humans; Isomerism

1. 35S-labelled chondroitin 4-sulphate proteoglycan was isolated from the mineralized elements of the developing incisor teeth of Harvard rats receiving intraperitoneal administration of Na235SO4. 2. The chondroitin 4-sulphate proteoglycan underwent a decrease in molecular size in fluorotic teeth as judged by gel filtration on Sepharose 2B. 3. When examined by anion-exchange chromatography on DEAE cellulose-52, the proteoglycan from fluorotic teeth resolved into four peaks in comparison with the material from non-fluorotic teeth, which exhibited only a single major peak. 4. Both the single peak from non-fluoridated teeth and the four peaks from the fluorotic teeth were further resolved on cellulose acetate electrophoresis. 5. Isolated chondroitin 4-sulphate chains obtained from fluorotic teeth also were of smaller molecular size as judged by gel filtration on Sephadex G-150. 6. Some possible influences of fluoride on the metabolism of these connective-tissue components in the developing rat incisor are discussed.

Topics: Amino Acids; Animals; Chondroitin Sulfates; Chromatography, DEAE-Cellulose; Chromatography, Gel; Fluorosis, Dental; Glycosaminoglycans; In Vitro Techniques; Incisor; Male; Molecular Weight; Proteoglycans; Rats

Demineralized sections of fluorinated bones and teeth have been studied by autoradiography following in vitro uptake of Ca(45) or S(35)O(4). The portions of tissue which do not become mineralized (cartilage, prebone, predentine, and precementum) show an increased Ca(45) uptake apparently related to an increase in chondroitin sulfate content in fluorosis. The tissues from the fluoride-fed animals show an increase of in vitro uptake of sulfur in the tissues which become mineralized (bone, dentine, cementum).

Topics: Animals; Autoradiography; Bone and Bones; Calcification, Physiologic; Calcium; Cartilage; Chondroitin Sulfates; Fluoride Poisoning; Fluorides; Fluorosis, Dental; In Vitro Techniques; Phosphates; Sulfates; Swine; Tooth