Baseline expression and effect of TGF-beta 1 on type I and III collagen mRNA and protein synthesis in human odontoblasts and pulp cells in vitro.
Since growth factors have been suggested to regulate dentin collagen formation in response to external irritation, we investigated the effect of TGF-beta 1 on pro alpha 1 (I) collagen mRNA expression in cultured mature human odontoblasts and pulpal fibroblasts, as well as cultured human pulp tissue, using quantitative PCR. Cultured gingival fibroblasts (GF) and osteoblasts (OB) served as controls. Also, type I collagen synthesis in cultured odontoblasts and pulp tissue, as well as type III collagen synthesis in odontoblasts, were studied by measuring respective procollagen (PINP and PIIINP) secretion into culture media with radio-immunoassay (RIA). Odontoblasts expressed significantly higher basic level of type I collagen mRNA than pulp tissue or pulp fibroblasts in culture, but markedly lower level than GF and OB cells. TGF-beta 1 (10 ng/ml) had negligible effects on type I collagen mRNA expression or PINP synthesis in cultured odontoblasts and pulp tissue, and PIIINP synthesis in the odontoblasts. In PF cells, the effect of TGF-beta 1 depended on culturing conditions; a 6-fold increase in mRNA expression was observed using serum-free medium but no effect was seen in the cells cultured with 10% FBS. In contrast, GF cells serving as controls were not markedly affected by the culture conditions, with 2-3-fold increase in mRNA expression by TGF-beta 1. These experiments demonstrate that mature human odontoblasts are capable of synthesizing type III collagen protein, and that TGF-beta 1 has negligible effect on mature human odontoblast and pulp tissue collagen expression.
Palosaari
H
H
Institute of Dentistry, University of Oulu, Oulu, Finland.
Tasanen
K
K
Risteli
J
J
Larmas
M
M
Salo
T
T
Tjäderhane
L
L
D000293:Adolescent; D000328:Adult; D002478:Cells, Cultured; D003094:Collagen / Q000096:biosynthesis / Q000235:genetics*; D017077:Culture Media, Conditioned / Q000737:chemistry; D003782:Dental Pulp / Q000187:drug effects / Q000378:metabolism*; D005347:Fibroblasts / Q000187:drug effects / Q000378:metabolism; D019084:Fluorescent Antibody Technique, Indirect; D005881:Gingiva / Q000166:cytology; D006801:Humans; D009804:Odontoblasts / Q000187:drug effects / Q000378:metabolism*; D010446:Peptide Fragments / Q000096:biosynthesis; D011347:Procollagen / Q000096:biosynthesis; D014176:Protein Biosynthesis; D012333:RNA, Messenger / Q000096:biosynthesis*; D016212:Transforming Growth Factor beta / Q000096:biosynthesis* / Q000235:genetics / Q000494:pharmacology; D053773:Transforming Growth Factor beta1
D017077:Culture Media, Conditioned; D010446:Peptide Fragments; D011347:Procollagen; D012333:RNA, Messenger; C508960:TGFB1 protein, human; D016212:Transforming Growth Factor beta; D053773:Transforming Growth Factor beta1; C047202:procollagen Type I N-terminal peptide; C041876:procollagen Type III-N-terminal peptide; D003094:Collagen