[The effect of extracellular signal-regulated kinase 1/2 signaling pathway on the expression of transforming growth factor-beta1 in lung fibroblast activated by silicon dioxide].
OBJECTIVE
To investigate the effect and regulation of extracellular signal-regulated kinase (ERK1/2) signaling pathway on the expression of transforming growth factor-beta1 (TGF-beta1) in human embryonic lung fibroblasts induced by SiO2.


METHODS
Human alveolar macrophages were collected from a silicotic patient by bronchoalveolar lavage and in the presence or absence of SiO2 (50 ug/ml) exposition for 18h, and then the conditioned supernatants were used to incubate HELF. The expressions of TGF-beta1, of the HELF acted with the conditioned AM supernatant fluid were detected with the immunocytochemistry method after treatment with PD98059 of inhibitor of ERK.


RESULTS
The expression of TGF-beta1 in HELF of the SiO2 treatment group (OD value is 0.322 7 +/- 0.023 8) exceed blank group (OD value is 0.163 7 +/- 0.019 6) and AM control group (OD value is 0.240 6 +/- 0.022 5) by the immunocytochemistry method. But the expression of TGF-beta1 had reduction in some extent in the PD98059 intervention group (OD value is 0.271 1 +/- 0.022 9). The values were statistically different (P < 0.05).


CONCLUSIONS
ERK inhibitor PD98059 have inhibition effect on the expression of transforming growth factor-beta1 and expression of cytokine of human embryonic lung fibroblasts stimulated by SiO2. The study indicate that the proliferation and collagen production of HELF activated by SiO2 are mediated by ERK/MAPK signal pathway in some extent. PD98059 may antagonizes silica-induced lung fibrosis by inhibiting the expression of transforming growth factor-beta1.
Department of Pathology, Hebei United University, Tangshan, Hebei Province 063000, China.
Li
L
Feng
Lan
L
Zhu
Jing
J
Zhao
Hai-Bing
HB
Peng
Xian-Hua
XH
Wang
D001992:Bronchoalveolar Lavage Fluid / Q000166:cytology; D002478:Cells, Cultured; D005347:Fibroblasts / Q000378:metabolism*; D005419:Flavonoids / Q000494:pharmacology; D006801:Humans; D008168:Lung / Q000166:cytology / Q000378:metabolism; D020935:MAP Kinase Signaling System; D016676:Macrophages, Alveolar / Q000166:cytology / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D012822:Silicon Dioxide / Q000009:adverse effects*; D012829:Silicosis / Q000378:metabolism*; D053773:Transforming Growth Factor beta1 / Q000378:metabolism*
D005419:Flavonoids; D053773:Transforming Growth Factor beta1; D012822:Silicon Dioxide; C093973:2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one