Evaluation of the effect of antiarthritic drugs on the secretion of proteoglycans by lapine chondrocytes using a novel assay procedure.
A new method is described for separating free 35SO4-- from 35SO4 labelled proteoglycans synthesised by rabbit articular chondrocytes cultured in the presence of excess 35SO4--. The procedure uses the low solubility product of barium sulphate to remove, by precipitation, free 35SO4-- from culture medium. Optimum recovery of 35SO4 labelled proteoglycans was achieved after papain digestion to release 35SO4-glycosaminoglycans, and addition of chondroitin sulphate before the precipitation step. Using this assay, we studied the effect of six drugs-indomethacin, diclofenac, sodium pentosan polysulphate, glycosaminoglycan polysulphate ester, tiaprofenic acid, and ketoprofen-on the secretion into the medium of labelled proteoglycans by lapine chondrocytes. The six drugs were tested at 0.1, 1, 10, 50, and 100 micrograms/ml over four consecutive 48 hour culture periods. A consistent concentration-response pattern was found for the four non-steroidal anti-inflammatory drugs (NSAIDs) studied. Generally they inhibited proteoglycan secretion at 50 and 100 micrograms/ml but had no effect at lower concentrations. Inhibition of secretion was strongest with indomethacin and diclofenac at 50 and 100 micrograms/ml. In contrast with the NSAIDs studied, the two sulphated polysaccharides (sodium pentosan polysulphate and glycosaminoglycan polysulphate ester) at low concentrations increased proteoglycan secretion by chondrocytes, with maximal stimulation occurring at 1 microgram/ml. Sodium pentosan polysulphate, but not glycosaminoglycan polysulphate ester, showed inhibitory activity at 50 and 100 micrograms/ml.
Collier
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Raymond Purves Research Laboratories, University of Sydney, Royal North Shore Hospital, St Leonards, NSW, Australia.
Ghosh
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D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000494:pharmacology*; D002358:Cartilage, Articular / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D002478:Cells, Cultured; D004008:Diclofenac / Q000494:pharmacology; D006025:Glycosaminoglycans / Q000494:pharmacology; D007213:Indomethacin / Q000494:pharmacology; D007660:Ketoprofen / Q000494:pharmacology; D008722:Methods; D010426:Pentosan Sulfuric Polyester / Q000494:pharmacology; D011422:Propionates / Q000494:pharmacology; D011509:Proteoglycans / Q000032:analysis / Q000096:biosynthesis*; D011817:Rabbits
D000894:Anti-Inflammatory Agents, Non-Steroidal; D006025:Glycosaminoglycans; D011422:Propionates; D011509:Proteoglycans; D004008:Diclofenac; C021270:tiaprofenic acid; C013786:A73025; D010426:Pentosan Sulfuric Polyester; D007660:Ketoprofen; D007213:Indomethacin