Serum amyloid A, an acute-phase protein, modulates proteoglycan synthesis in cultured murine peritoneal macrophages.
Cultured peritoneal macrophages obtained from azocasein-injected mice were found to produce several fold more cell-associated and medium proteoglycans than peritoneal macrophages from untreated mice. Since serum amyloid A (an acute-phase protein) is also upregulated following injections of azocasein, we questioned whether its production was the immediate agent stimulating proteoglycan formation. Cultured peritoneal macrophages from untreated mice were then incubated with varying concentrations of SAA, resulting in a similar dose-dependent several fold increase in proteoglycan production. Of particular note was a disproportionate increase in cell-associated heparan sulfate proteoglycans in both experimental groups and of dermatan sulfate and chondroitin sulfate proteoglycans when cells were incubated in the presence of SAA in the culture medium. These results indicate a potentially important function of SAA in directing specific modifications in inflammatory conditions where increase in macrophage proteoglycans may play direct roles.
Elliott-Bryant
R
R
Edith Nourse Rogers Memorial Veterans Hospital, Bedford, Massachusetts, 01730, USA.
Silbert
J E
JE
Sugumaran
G
G
D000818:Animals; D002478:Cells, Cultured; D011508:Chondroitin Sulfate Proteoglycans / Q000096:biosynthesis; D003871:Dermatan Sulfate / Q000096:biosynthesis; D019812:Heparan Sulfate Proteoglycans / Q000096:biosynthesis; D007249:Inflammation / Q000209:etiology / Q000378:metabolism; D018836:Inflammation Mediators / Q000378:metabolism; D017737:Macrophages, Peritoneal / Q000187:drug effects / Q000378:metabolism*; D051379:Mice; D011509:Proteoglycans / Q000096:biosynthesis*; D000685:Serum Amyloid A Protein / Q000378:metabolism* / Q000494:pharmacology
D011508:Chondroitin Sulfate Proteoglycans; D019812:Heparan Sulfate Proteoglycans; D018836:Inflammation Mediators; D011509:Proteoglycans; D000685:Serum Amyloid A Protein; C032649:dermatan sulfate proteoglycan; D003871:Dermatan Sulfate