Effect of interleukin-1beta on transforming growth factor-beta and bone morphogenetic protein-2 expression in human periodontal ligament and alveolar bone cells in culture: modulation by avocado and soybean unsaponifiables.
BACKGROUND
In periodontal disease, interleukin-1beta (IL-1beta) is responsible for the matrix breakdown through excessive production of degrading enzymes by periodontal ligament fibroblasts and osteoblasts. Transforming growth factor-beta (TGF-beta) plays an important role in tissue regeneration as one of the factors capable of counteracting IL-1beta effects. In this study, we investigated the in vitro effect of avocado and soya unsaponifiables (ASU) on the expression of TGF-beta1, TGF-beta2, and bone morphogenetic protein-2 (BMP-2) by human periodontal ligament (HPL) and human alveolar bone (HAB) cells in the presence of IL-1beta.


METHODS
HPL and HAB cells were incubated for 48 hours with ASU (10 microg/ml) in the presence or absence of IL-1beta (10 ng/ml). The steady-state levels of TGF-beta1, TGF-beta2, and BMP-2 mRNAs were determined by Northern blot or reverse transcription-polymerase chain reaction (RT-PCR). The amounts of TGF-beta1 and TGF-beta2 proteins were measured by enzyme-linked immunosorbent assay (ELISA).


RESULTS
The data indicated that IL-1beta strongly decreases the expression of TGF-beta1 and TGF-beta2 by HPL cells. ASU were capable of opposing the cytokine effect. In HAB cells, TGF-beta1 and BMP-2 mRNA levels were downregulated by the cytokine. ASU were found to reverse the IL-1beta-inhibiting effect. In contrast, the cytokine stimulated the production of TGF-beta2 in alveolar bone cells, with no significant effect of ASU.


CONCLUSIONS
The results indicate that the IL-1beta-driven erosive effect in periodontitis could be enhanced by a decreased expression of members of the TGF-beta family. The ASU stimulation of TGF-beta1, TGF-beta2, and BMP-2 expression may explain their promoting effects in the treatment of periodontal disorders, at least partly. These findings support the hypothesis that ASU could exert a preventive action on the deleterious effects exerted by IL-1beta in periodontal diseases.
Andriamanalijaona
R
R
Laboratory of Connective Tissue Biochemistry, Faculty of Medicine, and Maxillary-Facial Surgery Department, Universitary Hospital Center, Caen, France.
Benateau
H
H
Barre
P E
PE
Boumediene
K
K
Labbe
D
D
Compere
J F
JF
Pujol
J P
JP
D000293:Adolescent; D000328:Adult; D000539:Alveolar Process / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins / Q000096:biosynthesis*; D002478:Cells, Cultured; D005260:Female; D005347:Fibroblasts / Q000187:drug effects / Q000378:metabolism; D006461:Hemolysis; D006801:Humans; D018836:Inflammation Mediators / Q000037:antagonists & inhibitors*; D007375:Interleukin-1 / Q000037:antagonists & inhibitors*; D008297:Male; D010513:Periodontal Ligament / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D027421:Persea / Q000737:chemistry; D010938:Plant Oils / Q000737:chemistry / Q000494:pharmacology*; D013024:Soybean Oil / Q000737:chemistry / Q000494:pharmacology; D013261:Sterols / Q000494:pharmacology; D016212:Transforming Growth Factor beta / Q000096:biosynthesis*; D015854:Up-Regulation
C525718:BMP2 protein, human; D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins; D018836:Inflammation Mediators; D007375:Interleukin-1; D010938:Plant Oils; D013261:Sterols; D016212:Transforming Growth Factor beta; D013024:Soybean Oil