Effect of bone morphogenetic protein-2 (BMP-2) on matrix production, other BMPs, and BMP receptors in rat intervertebral disc cells.
OBJECTIVE
An in vitro experiment study using rat disc cells was carried out to determine the effect of bone morphogenetic protein-2 (BMP-2) on extracellular matrix production, other BMPs, and BMP receptors (BMPRs).


METHODS
Cells from the anulus fibrosus and transition zone were harvested and cultured. When the cells reached 80% confluence, BMP-2 was added to reach a final concentration of 200 ng/mL. Three days later, the culture media were collected for the assay of sulfated glycosaminoglycans (sGAG) and collagen types I and II. The cells were harvested for RNA extraction to determine the genes expressed. All experiments were performed at least three times to ensure repeatability.


RESULTS
BMP-2 significantly increased aggrecan and collagen type II mRNA expression 8.30 and 4.61 times, respectively, and decreased versican mRNA expression 0.54 times as compared with control. Collagen type I production and mRNA level were not changed. BMP-2 significantly increased transforming growth factor-beta1 (TGFbeta1) and BMP-7 mRNA expression 2.32 and 2.45 times, respectively, compared with control. There was no significant change in BMP-6 mRNA expression. BMPR type IB and II mRNA expressions were increased and BMPR type 1A mRNA expression was decreased, but none of these differences was significant.


CONCLUSIONS
The results of this study show that in rat intervertebral disc cells, BMP-2 increases aggrecan and collagen type II mRNA expression and decreases versican gene expression. BMP-2 also up-regulates mRNA expression for BMP-7 and TGFbeta but has no significant effect on the BMPRs.
Li
Jun
J
Emory University, Atlanta Veterans Affairs Medical Center, Atlanta, Georgia, USA.
Yoon
S Tim
ST
Hutton
William C
WC
D053674:Aggrecans; D000818:Animals; D055396:Bone Morphogenetic Protein 2; D055419:Bone Morphogenetic Protein 7; D052004:Bone Morphogenetic Protein Receptors; D052005:Bone Morphogenetic Protein Receptors, Type I; D052006:Bone Morphogenetic Protein Receptors, Type II; D019485:Bone Morphogenetic Proteins / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology*; D002356:Cartilage / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D002478:Cells, Cultured; D024042:Collagen Type I / Q000235:genetics; D024043:Collagen Type II / Q000235:genetics; D005109:Extracellular Matrix / Q000187:drug effects* / Q000378:metabolism; D016326:Extracellular Matrix Proteins / Q000235:genetics; D015870:Gene Expression / Q000187:drug effects / Q000502:physiology; D006025:Glycosaminoglycans / Q000235:genetics; D007403:Intervertebral Disc / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D037181:Lectins, C-Type; D017346:Protein Serine-Threonine Kinases / Q000235:genetics; D011509:Proteoglycans / Q000235:genetics; D012333:RNA, Messenger / Q000187:drug effects / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D017978:Receptors, Growth Factor / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D012038:Regeneration / Q000187:drug effects / Q000502:physiology; D016212:Transforming Growth Factor beta / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology*; D053773:Transforming Growth Factor beta1; D015854:Up-Regulation / Q000187:drug effects / Q000235:genetics
C508321:Acan protein, rat; D053674:Aggrecans; C525720:Bmp2 protein, rat; C525821:Bmp7 protein, rat; D055396:Bone Morphogenetic Protein 2; D055419:Bone Morphogenetic Protein 7; D019485:Bone Morphogenetic Proteins; D024042:Collagen Type I; D024043:Collagen Type II; D016326:Extracellular Matrix Proteins; D006025:Glycosaminoglycans; D037181:Lectins, C-Type; D011509:Proteoglycans; D012333:RNA, Messenger; D017978:Receptors, Growth Factor; C508962:Tgfb1 protein, rat; D016212:Transforming Growth Factor beta; D053773:Transforming Growth Factor beta1; D017346:Protein Serine-Threonine Kinases; C498220:Bmpr2 protein, rat; D052004:Bone Morphogenetic Protein Receptors; D052005:Bone Morphogenetic Protein Receptors, Type I; D052006:Bone Morphogenetic Protein Receptors, Type II