C-type natriuretic peptide regulates cellular condensation and glycosaminoglycan synthesis during chondrogenesis.
C-type natriuretic peptide (CNP) has recently been identified as a key anabolic regulator of endochondral bone growth, but the cellular and molecular mechanisms involved are incompletely understood. Although CNP has been shown to stimulate proliferation and hypertrophic differentiation of growth plate chondrocytes, it is unknown whether CNP affects the earliest stages of endochondral bone development, condensation of mesenchymal precursor cells, and chondrogenesis. Here we demonstrate that CNP increases the number of chondrogenic condensations of mouse embryonic limb bud cells in micromass culture. This is accompanied by increased expression of the cell adhesion molecule N-cadherin. In addition, CNP stimulates glycosaminoglycan synthesis as indicated by increased Alcian blue staining. However, expression of the chondrogenic transcription factors Sox9, -5, and -6 or of the main extracellular matrix genes encoding collagen II and aggrecan is not affected by CNP. Instead, we show that CNP increases expression of enzymes involved in chondroitin sulfate synthesis, a required step in the production of cartilage glycosaminoglycans. In summary, we demonstrate a novel role of CNP in promoting chondrogenesis by stimulating expression of molecules involved in cell adhesion molecules and glycosaminoglycan synthesis.
Woods
Anita
A
Department of Physiology and Pharmacology, University of Western Ontario, London, Ontario, Canada.
Khan
Sameena
S
Beier
Frank
F
D000818:Animals; D015820:Cadherins / Q000378:metabolism; D019902:Chondrocytes / Q000187:drug effects / Q000502:physiology*; D020219:Chondrogenesis / Q000187:drug effects / Q000502:physiology*; D006152:Cyclic GMP / Q000494:pharmacology; D016326:Extracellular Matrix Proteins / Q000378:metabolism; D015870:Gene Expression; D006025:Glycosaminoglycans / Q000096:biosynthesis*; D006609:High Mobility Group Proteins / Q000502:physiology; D051379:Mice; D008815:Mice, Inbred Strains; D020098:Natriuretic Peptide, C-Type / Q000494:pharmacology / Q000502:physiology*; D010430:Pentosyltransferases / Q000235:genetics / Q000378:metabolism; D011509:Proteoglycans / Q000378:metabolism; D017461:Receptors, Atrial Natriuretic Factor / Q000378:metabolism; D055758:SOX9 Transcription Factor; D015398:Signal Transduction / Q000502:physiology; D014157:Transcription Factors / Q000502:physiology; D015854:Up-Regulation; D000097608:UDP Xylose-Protein Xylosyltransferase; D000099249:Proteoglycan Link Protein
D015820:Cadherins; D006152:Cyclic GMP; D016326:Extracellular Matrix Proteins; D006025:Glycosaminoglycans; D006609:High Mobility Group Proteins; D020098:Natriuretic Peptide, C-Type; D010430:Pentosyltransferases; D011509:Proteoglycans; D017461:Receptors, Atrial Natriuretic Factor; D055758:SOX9 Transcription Factor; D014157:Transcription Factors; D000097608:UDP Xylose-Protein Xylosyltransferase; D000099249:Proteoglycan Link Protein; C527933:Sox9 protein, mouse; C073616:atrial natriuretic factor receptor C