[Regulating effects of transforming growth factor-beta (TGF-beta) on gene expression of collagen type II in human intervertebral discs].
OBJECTIVE
To assess the regulating effects of TGF-beta on gene expression of collagen type II in the human intervertebral discs.


METHODS
In situ hybridization was used to investigate the effect of TGF-beta1 on collagen mRNA in confluent primary and passaged monolayer cell cultures of annulus fibrosus (AF) as well as nucleus pulposus (NP). The mean photodensitometry of cell smears as semi-quantitative analysis was evaluated by VIDAS software.


RESULTS
In primary cultures, 1 ng/ml and 10 ng/ml TGF-beta1 inhibited the collagen type II mRNA levels by 74.6% and 60.2% respectively in AF; they also inhibited the mRNA levels by 69.6% and 55.5% respectively in NP. In passaged cultures in which the notochordal cells and chondrocytes were in dedifferentiation status, 1 ng/ml and 10 ng/ml TGF-beta1 increased the collagen type II mRNA levels by 151% and 166% respectively in AF and also increased the mRNA levels by 145% and 198% respectively in NP.


CONCLUSIONS
The regulation effect of TGF-beta on collagen type II gene expression is dependent on whether the cells are fully differentiated or undergoing phenotype loss, and TGF-beta may play an important role in the repair process during early disc degeneration, especially in nucleus pulposus.
Chen
Y
Y
Department of Orthopaedics, Affiliated Hospital of Medical College, Qingdao University, Qingdao 266003, China.
Hu
Y
Y
Lü
Z
Z
D002478:Cells, Cultured; D024043:Collagen Type II / Q000235:genetics*; D015870:Gene Expression / Q000187:drug effects*; D006801:Humans; D017403:In Situ Hybridization; D007403:Intervertebral Disc / Q000166:cytology / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D053773:Transforming Growth Factor beta1 / Q000494:pharmacology*
D024043:Collagen Type II; D012333:RNA, Messenger; D053773:Transforming Growth Factor beta1