Cysteine cathepsins in human dentin-pulp complex.
BACKGROUND
Collagen-degrading matrix metalloproteinases (MMPs) are expressed by odontoblasts and present in dentin. We hypothesized that odontoblasts express other collagen-degrading enzymes such as cysteine cathepsins, and their activity would be present in dentin, because odontoblasts are known to express at least cathepsin D. Effect of transforming growth factor beta (TGF-beta) on cathepsin expression was also analyzed.


METHODS
Human odontoblasts and pulp tissue were cultured with and without TGF-beta, and cathepsin gene expression was analyzed with DNA microarrays. Dentin cathepsin and MMP activities were analyzed by degradation of respective specific fluorogenic substrates.


RESULTS
Both odontoblasts and pulp tissue demonstrated a wide range of cysteine cathepsin expression that gave minor responses to TGF-beta. Cathepsin and MMP activities were observed in all dentin samples, with significant negative correlations in their activities with tooth age.


CONCLUSIONS
These results demonstrate for the first time the presence of cysteine cathepsins in dentin and suggest their role, along with MMPs, in dentin modification with aging.
Tersariol
Ivarne L
IL
Centro Interdisciplinar de Investigação Bioquímica, Universidade de Mogi das Cruzes, São Paulo, Brazil.
Geraldeli
Saulo
S
Minciotti
Christiane L
CL
Nascimento
Fábio D
FD
Pääkkönen
Virve
V
Martins
Marília T
MT
Carrilho
Marcela R
MR
Pashley
David H
DH
Tay
Franklin R
FR
Salo
Tuula
T
Tjäderhane
Leo
L
D002403:Cathepsins / Q000145:classification / Q000378:metabolism*; D057056:Cysteine Proteases / Q000378:metabolism*; D003782:Dental Pulp / Q000201:enzymology*; D003804:Dentin / Q000201:enzymology*; D006801:Humans; D020782:Matrix Metalloproteinases / Q000378:metabolism; D009804:Odontoblasts / Q000201:enzymology*; D020411:Oligonucleotide Array Sequence Analysis
D002403:Cathepsins; D057056:Cysteine Proteases; D020782:Matrix Metalloproteinases