Catabolic effects of muramyl dipeptide on rabbit chondrocytes.
Muramyl dipeptide, an essential structure for the diverse biologic activities of bacterial cell wall peptidoglycan, inhibited the synthesis of glycosaminoglycan/proteoglycan in cultured rabbit costal chondrocytes in a dose-dependent manner. Muramyl dipeptide, as well as lipopolysaccharide and interleukin-1 alpha, also enhanced the release of 35S-sulfate-prelabeled glycosaminoglycan/proteoglycan from the cell layer, which seems to reflect, at least partially, the increasing degradation of glycosaminoglycan/proteoglycan. Five synthetic analogs of muramyl dipeptide known to be adjuvant active or adjuvant inactive were tested for their potential to inhibit synthesis of glycosaminoglycan/proteoglycan and to enhance the release of glycosaminoglycan/proteoglycan in chondrocytes. The structural dependence of these synthetic analogs on chondrocytes was found to parallel that of immunoadjuvant activity. These results suggest that muramyl dipeptide is a potent mediator of catabolism in chondrocytes.
Ikebe
T
T
Department of Biochemistry, Faculty of Dentistry, Kyushu University, Fukuoka, Japan.
Iribe
H
H
Hirata
M
M
Yanaga
F
F
Koga
T
T
D000119:Acetylmuramyl-Alanyl-Isoglutamine / Q000494:pharmacology*; D000276:Adjuvants, Immunologic / Q000494:pharmacology; D000818:Animals; D002356:Cartilage / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D006025:Glycosaminoglycans / Q000378:metabolism; D007375:Interleukin-1 / Q000494:pharmacology; D008070:Lipopolysaccharides / Q000494:pharmacology; D008297:Male; D011509:Proteoglycans / Q000378:metabolism; D011817:Rabbits; D013462:Sulfur Radioisotopes
D000276:Adjuvants, Immunologic; D006025:Glycosaminoglycans; D007375:Interleukin-1; D008070:Lipopolysaccharides; D011509:Proteoglycans; D013462:Sulfur Radioisotopes; D000119:Acetylmuramyl-Alanyl-Isoglutamine