Back
Full-text
Journal article

Effect of MALP-2, a Lipopeptide fromMycoplasma fermentans, on Bone Resorption In Vitro

  • Piec, Grazyna Department of Clinical Research, Bone Biology, University of Bern, CH-3010 Bern, Switzerland,1 and
  • Mirkovitch, Jelena Department of Clinical Research, Bone Biology, University of Bern, CH-3010 Bern, Switzerland,1 and
  • Palacio, Silvia Department of Clinical Research, Bone Biology, University of Bern, CH-3010 Bern, Switzerland,1 and
  • Mühlradt, Peter F. Immunobiology Research Group, Gesellschaft für Biotechnologische Forschung, D-38124-Braunschweig, Germany2
  • Felix, Rolf Department of Clinical Research, Bone Biology, University of Bern, CH-3010 Bern, Switzerland,1 and
Show more…
Published in:
  • Infection and Immunity. - American Society for Microbiology. - 1999, vol. 67, no. 12, p. 6281-6285
Immunology
Microbiology
Parasitology
Infectious Diseases
English ABSTRACT
Mycoplasmas may be associated with rheumatoid arthritis in various animal hosts. In humans, mycoplasma arthritis has been recorded in association with hypogammaglobulinemia. Mycoplasma fermentans is one mycoplasma species considered to be involved in causing arthritis. To clarify which mycoplasmal compounds contribute to the inflammatory, bone-destructive processes in arthritis, we used a well-defined lipopeptide, 2-kDa macrophage-activating lipopeptide (MALP-2) from M. fermentans, as an example of a class of macrophage-activating compounds ubiquitous in mycoplasmas, to study its effects on bone resorption. MALP-2 stimulated osteoclast-mediated bone resorption in murine calvaria cultures, with a maximal effect at around 2 nM. Anti-inflammatory drugs inhibited MALP-2-mediated bone resorption by about 30%. This finding suggests that MALP-2 stimulates bone resorption partially by stimulating the formation of prostaglandins. Since interleukin-6 (IL-6) stimulates bone resorption, we investigated IL-6 production in cultured calvaria. MALP-2 stimulated the liberation of IL-6, while no tumor necrosis factor was detectable. Additionally, MALP-2 stimulated low levels of NO in calvaria cultures, an effect which was strongly increased in the presence of gamma interferon, causing an inhibition of bone resorption. MALP-2 stimulated the bone-resorbing activity of osteoclasts isolated from long bones of newborn rats and cultured on dentine slices without affecting their number. In bone marrow cultures, MALP-2 inhibited the formation of osteoclasts. It appears that MALP-2 has two opposing effects: it increases the bone resorption in bone tissue by stimulation of mature osteoclasts but inhibits the formation of new ones.
Language
  • English
Open access status
bronze
Identifiers
Persistent URL
https://sonar.rero.ch/global/documents/131750
Statistics
Document views: 4 File downloads:
  • fulltext.pdf: 0