[Transforming growth factor-beta1 induced phenotypic differentiation of human lung fibroblasts through mitogen activated protein kinase-dependent pathway].
OBJECTIVE
To investigate the role of MAPK signal transduction in TGF-beta1 induced phenotypic differentiation of human lung fibroblasts.


METHODS
Human lung fibroblasts cell line (HLF-02) were cultured and then stimulated with 10 ng/ml TGF-beta1 for different time; SB203580 or PD98059 was added into culture medium to prevent p38 or Erk kinase pathway before incubating with TGF-beta1; the expression of alpha-smooth muscle actin (alpha-SMA) was detected by Western blotting and RT-PCR; Western blotting was used to assay phosphorylation of p38, Erk, and JNK kinase.


RESULTS
(1) In the process of stimulation by TGF-beta1, the alpha-SMA mRNA expression levels of 24, 48 and 72 h groups were 1.87 +/- 0.11, 2.49 +/- 0.10, 3.02 +/- 0.15 respectively; and the alpha-SMA protein expression levels of 24, 48 and 72 h groups were 3.20 +/- 0.14, 3.96 +/- 0.21, 4.57 +/- 0.13 respectively. (2) TGF-beta1 induced p38, Erk kinase phosphorylation but not JNK kinase. (3) The inhibitors SB203580 and PD98059 suppressed TGF-beta1-induced p38 kinase and Erk phosphorylation respectively. (4) SB203580 significantly attenuated TGF-beta1-induced alpha-SMA mRNA and protein expression (inhibition rate: 30% and 40%); PD98059 also significantly inhibited TGF-beta1-induced alpha-SMA mRNA and protein expression (inhibition rate: 10% and 20%).


CONCLUSIONS
TGF-beta1 is capable of inducing the phenotypic differentiation of HLF-02, which is regulated by p38 and Erk kinase signal pathway.
Hu
Yong-bin
YB
Department of Pathology, Xiang-Ya Medical School, Central South University, Changsha, Hunan Province 410013, China.
Feng
De-yun
DY
Peng
Jin-wu
JW
Chu
Ling
L
Lin
Zhi
Z
Zeng
Qing-fu
QF
D000199:Actins / Q000096:biosynthesis* / Q000235:genetics; D002460:Cell Line; D048049:Extracellular Signal-Regulated MAP Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D005347:Fibroblasts / Q000187:drug effects / Q000378:metabolism*; D005419:Flavonoids / Q000494:pharmacology; D006801:Humans; D007093:Imidazoles / Q000494:pharmacology; D008168:Lung / Q000166:cytology; D010641:Phenotype; D010766:Phosphorylation; D011725:Pyridines / Q000494:pharmacology; D012333:RNA, Messenger / Q000235:genetics; D053773:Transforming Growth Factor beta1 / Q000494:pharmacology*; D048051:p38 Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*
D000199:Actins; D005419:Flavonoids; D007093:Imidazoles; D011725:Pyridines; D012333:RNA, Messenger; D053773:Transforming Growth Factor beta1; D048049:Extracellular Signal-Regulated MAP Kinases; D048051:p38 Mitogen-Activated Protein Kinases; C093642:SB 203580; C093973:2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one