Separate effects of exogenous hyaluronic acid on proteoglycan synthesis and deposition in pericellular matrix by cultured chick embryo limb chondrocytes
Solursh, M.; Hardingham, T.E.; Hascall, V.C.; Kimura, J.H.
Developmental Biology 75(1): 121-129
ISSN/ISBN: 0012-1606 PMID: 7371989 DOI: 10.1016/0012-1606(80)90148-7
Effects of exogenous hyaluronic acid on cell cultures of chick embryo limb chondrocytes are reported. Exogenous hyaluronic acid (HA) can both depress the incorporation of 35SO4 into glycosaminoglycans and cause a displacement of newly synthesized proteoglycan from the cell layer to the culture medium. These 2 effects are mediated by distinct mechanisms. The displacement effect has a rapid onset (by 2 h) while the effect of exogenous HA on 35SO4 incorporation has a long latency (12 h). The displacement effect is produced by a lower concentration (5 .mu.g/ml) of hyaluronate oligomers than the effect on 35SO4 incorporation (50 .mu.g/ml). Displacement is produced only by hyaluronate oligomers that are decasaccharides or larger. The depression of 35SO4 incorporation is produced by tetrasaccharides as well as high MW HA. In fact, tetrasaccharides can depress 35SO4 incorporation without causing the displacement effect.