Insulin enhances the growth of cartilage in organ and tissue cultures of mouse neonatal mandibular condyle.
Condylar cartilages were cultured in the form of organ cultures on top of collagen sponges in medium containing 2% fetal calf serum and were treated with 3.5-350 nM insulin for 6 days. Doses of 175 nM of insulin caused a marked increase (+96%) in DNA synthesis and in proteoglycan production (+74%), features that manifested themselves structurally by a 60% increase in overall size of the cultured explants. Using a tissue culture system comprised of cartilage progenitor cells, insulin was found to enhance the differentiation of the progenitor cells so that by 6 days in culture an appreciable nodule of differentiated chondrocytes developed. The latter was surrounded by perichondrial cells whereas the extracellular matrix within the newly formed, insulin-induced, nodule reacted positively for cartilage-specific antigens (type II collagen and bone sialoprotein). It is suggested that insulin induces a direct stimulatory effect on progenitor cell proliferation, cartilage differentiation, and extracellular matrix deposition.
Maor
G
G
Laboratory for Musculoskeletal Research, Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa.
Silbermann
M
M
von der Mark
K
K
Heingard
D
D
Laron
Z
Z
D000818:Animals; D000831:Animals, Newborn; D001345:Autoradiography; D002356:Cartilage / Q000166:cytology / Q000187:drug effects* / Q000254:growth & development; D002454:Cell Differentiation / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D046508:Culture Techniques; D004247:DNA / Q000096:biosynthesis; D007328:Insulin / Q000494:pharmacology*; D007334:Insulin-Like Growth Factor I / Q000494:pharmacology; D008335:Mandibular Condyle / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism; D051379:Mice; D008813:Mice, Inbred ICR; D008856:Microscopy, Fluorescence; D009924:Organ Culture Techniques; D011509:Proteoglycans / Q000096:biosynthesis; D017526:Receptor, IGF Type 1 / Q000502:physiology
D007328:Insulin; D011509:Proteoglycans; D007334:Insulin-Like Growth Factor I; D004247:DNA; D017526:Receptor, IGF Type 1