Effect of diacetylrhein on the phagocytosis of polymorphonuclear leucocytes and its influence on the biosynthesis of hyaluronate in synovial cells.
1. The influence of diacetylrhein on the luminol-induced chemiluminescence of zymosan-activated polymorphonuclear leucocytes (PMNL) was investigated. At a concentration of 4 x 10(-5) mol/l diacetylrhein an inhibition of about 40% was found. 2. A model for the degradation of hyaline cartilage by frustrated phagocytosis was developed, in which human polymorphonuclear leucocytes cause a release of glycosaminoglycan peptides from hyaline cartilage slices (bovine nasal septum). We observed a 20% inhibition of this release at a concentration of 10(-4) mol/l diacetylrhein. 3. Human synovial fibroblasts synthesize the glycosaminoglycan hyaluronate. As a parameter of the rate of hyaluronate synthesis we measured the incorporation of 14C-glucosamine into hyaluronate. At a concentration of 2 x 10(-4) mol/l diacetylrhein a 4-fold increase of 14C-glucosamine incorporation in the membrane fraction of the synovial cells (tryptic fraction) and a 1.6-fold elevation of glucosamine release into the medium was measured. The synovial fibroblasts show a higher (1.5-fold) glucose consumption and lactate production in the presence of diacetylrhein (2 x 10(-4) mol/l).
Institut für Klinische Chemie und Pathobiochemie, Medizinischen Fakultät Rheinisch-Westfälischen, Technischen Hochschule Aachen, (Fed. Rep. of Germany).
R N
RN
Schöngen
B M
BM
Giannetti
E
E
van de Leur
R
R
Reinards
H
H
Greiling
D000328:Adult; D000818:Animals; D000880:Anthraquinones / Q000494:pharmacology*; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000494:pharmacology*; D002417:Cattle; D002478:Cells, Cultured; D003470:Culture Media; D006025:Glycosaminoglycans / Q000378:metabolism; D006801:Humans; D006820:Hyaluronic Acid / Q000096:biosynthesis*; D008163:Luminescent Measurements; D008297:Male; D009504:Neutrophils / Q000187:drug effects*; D010587:Phagocytosis / Q000187:drug effects*; D013582:Synovial Fluid / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*
D000880:Anthraquinones; D000894:Anti-Inflammatory Agents, Non-Steroidal; D003470:Culture Media; D006025:Glycosaminoglycans; C025292:diacerein; D006820:Hyaluronic Acid