D-penicillamine inhibition of interleukin-1 production: a possible mechanism for its effect on synovial collagen synthesis?
Collagen production was investigated in cultured rabbit synovial fibroblasts exposed in vitro to D-penicillamine (D-Pen). The results show that these cells are rather insensitive to the drug since only a slight increase of the collagen amount secreted was observed for 48-h exposure to concentrations of 200-400 micrograms/ml. However, fibroblasts derived from the synovium of arthritic rabbits proved to be more susceptible to D-Pen, responding by a marked increase of collagen secretion even for concentrations of 50 micrograms/ml. This finding suggests that synovial fibroblasts of arthritic patients, probably stimulated by the inflammation process, could be target cells for the D-Pen action. The activities of 4-prolyl-hydroxylase (4-PH) and galactosylglucosyl-transferase (GGT) were assayed in the same cultures. A correlation has been found between the 4-PH activity and the collagen amount produced. In contrast, no alteration in the level of GGT on exposure to D-Pen was detected. Finally, D-Pen was shown to reduce in vitro the production of collagen-inhibiting factors by phytohaemagglutinin-stimulated mononuclear cells. This effect was associated with an inhibition of the release of monocyte cell factor (MCF/interleukin-1), suggesting that D-Pen could indirectly affect synovial collagen synthesis by interfering with interleukin-1 secretion.
D000818:Animals; D002478:Cells, Cultured; D003094:Collagen / Q000096:biosynthesis*; D005347:Fibroblasts / Q000187:drug effects / Q000378:metabolism; D007375:Interleukin-1 / Q000096:biosynthesis*; D010396:Penicillamine / Q000494:pharmacology*; D011393:Procollagen-Proline Dioxygenase / Q000378:metabolism; D011817:Rabbits; D013583:Synovial Membrane / Q000187:drug effects* / Q000378:metabolism
D007375:Interleukin-1; D003094:Collagen; D011393:Procollagen-Proline Dioxygenase; D010396:Penicillamine