The modulation of tissue-specific gene expression in rat nasal chondrocyte cultures by bioactive glasses.
Since bone repair may occur, following endochondral ossification, we have investigated the behaviour of chondrocytes isolated from nasal septum cartilage of foetal rats and cultured up to 21 days in the presence of a melt-derived bioactive glass (Bioglass 45S5) and a less reactive glass with 60 wt% silica content (60S). In both cultures, chondrocytes proliferate and form typical cartilaginous nodules on day 5 of cultures. However, on day 12, the nodules in contact with 45S5 granules became darker than in 60S cultures, corresponding to the emergence of matrix biomineralization. Transmission electron microscopy showed a collagen-rich matrix composed of densely packed fibres and mineralized foci formed of needle-shaped crystals in contact with an electron-dense layer located at the periphery of the material. The specific activity of alkaline phosphatase was significant higher in 45S5 cultures on day 15 than in 60S cultures. Real time RT-PCR was used to monitor gene expression levels of specific chondrogenic markers. The transcription factor Sox9 was expressed throughout the culture period, but with no significant differences between the two kinds of cultures. In contrast, Runx2 expression was higher in experiment cultures on day 12. Type II collagen mRNA and aggrecan, showed an almost similar expression pattern with a strong expression at the beginning of cultures but higher in experiment cultures. Indian hedgehog was strongly expressed between day 9 and 12 with a significant stimulation in 45S5 cultures. Similarly, type X collagen mRNA seemed to be up-regulated in 45S5 cultures on day 20. In conclusion, this study shows hat 45S5 Bioglass has the ability to support the growth of chondrocytes and to stimulate some chondrogenic molecular markers.
Asselin
Audrey
A
Laboratoire Biologie Orofaciale et Pathologie, INSERM E0110, Institut Biomédical des Cordeliers, Université Paris 7, UFR d'Odontologie, Esc. E-2è étage, Paris Cedex 06 F-75270, France.
Hattar
Susan
S
Oboeuf
Martine
M
Greenspan
David
D
Berdal
Ariane
A
Sautier
Jean-Michel
JM
D053674:Aggrecans; D000469:Alkaline Phosphatase / Q000378:metabolism; D000818:Animals; D002454:Cell Differentiation / Q000187:drug effects; D002478:Cells, Cultured; D002516:Ceramics / Q000494:pharmacology*; D019902:Chondrocytes / Q000187:drug effects* / Q000378:metabolism / Q000648:ultrastructure; D024043:Collagen Type II / Q000235:genetics; D024121:Collagen Type X / Q000235:genetics; D050659:Core Binding Factor Alpha 1 Subunit; D005109:Extracellular Matrix / Q000378:metabolism; D016326:Extracellular Matrix Proteins / Q000235:genetics; D015870:Gene Expression / Q000187:drug effects* / Q000235:genetics; D005898:Glass; D053823:Hedgehog Proteins; D006609:High Mobility Group Proteins / Q000235:genetics; D037181:Lectins, C-Type; D046529:Microscopy, Electron, Transmission; D008858:Microscopy, Phase-Contrast; D009300:Nasal Septum / Q000166:cytology; D009363:Neoplasm Proteins / Q000235:genetics; D011509:Proteoglycans / Q000235:genetics; D051381:Rats; D017207:Rats, Sprague-Dawley; D020133:Reverse Transcriptase Polymerase Chain Reaction; D055758:SOX9 Transcription Factor; D015534:Trans-Activators / Q000235:genetics; D014157:Transcription Factors / Q000235:genetics
C508321:Acan protein, rat; D053674:Aggrecans; D024043:Collagen Type II; D024121:Collagen Type X; D050659:Core Binding Factor Alpha 1 Subunit; D016326:Extracellular Matrix Proteins; D053823:Hedgehog Proteins; D006609:High Mobility Group Proteins; D037181:Lectins, C-Type; D009363:Neoplasm Proteins; D011509:Proteoglycans; D055758:SOX9 Transcription Factor; D015534:Trans-Activators; D014157:Transcription Factors; C425330:bioactive glass 45S5; D000469:Alkaline Phosphatase