title: Alterations in chondrocyte morphology, proliferation and binding of 35SO4 due to Fe(III), Fe(II), ferritin and haemoglobin in vitro.
abstract: Lapine articular chondrocytes in vitro were used to study the effects of Fe3+, Fe2+, ferritin and haemoglobin on cell proliferation, synthesis of proteoglycans and morphological structure. Fe3+ (10, 100 and 500 micrograms/ml) reduced the DNA content of cultures by approximately 35% as well as inhibiting proteoglycan synthesis. Chondrocytes showed positive cytoplasmic staining for both ferric and ferrous ions at the 500 micrograms/ml concentration. Fe2+ (100 micrograms/ml) also decreased DNA content and proteoglycan synthesis, although no iron uptake by the chondrocytes could be detected. Ferritin (1.0, 0.5 and 0.1 micrograms/ml) elicited a significant inhibition of proteoglycan synthesis without affecting cellular DNA synthesis. 1 and 5 micrograms/ml of haemoglobin each reduced the DNA content of cultures by 60%, whilst markedly inhibiting proteoglycan synthesis (75 and 99% respectively). None of the substances tested caused chondrocyte toxicity. The ability of Fe3+, Fe2+, ferritin and, in particular, haemoglobin to inhibit chondrocyte proteoglycan synthesis may represent a pathway whereby cartilage is susceptible to destruction in the haemophilic joint.
mesh_terms: D000818:Animals; D002358:Cartilage, Articular / Q000378:metabolism / Q000473:pathology*; D002455:Cell Division / Q000187:drug effects*; D002478:Cells, Cultured; D004247:DNA / Q000032:analysis; D005293:Ferritins / Q000494:pharmacology*; D006454:Hemoglobins / Q000494:pharmacology*; D007501:Iron / Q000494:pharmacology*; D011509:Proteoglycans / Q000096:biosynthesis; D011817:Rabbits
chemical_list: D006454:Hemoglobins; D011509:Proteoglycans; D004247:DNA; D005293:Ferritins; D007501:Iron