The role of transforming growth factor-β1/connective tissue growth factor signaling pathway in paraquat-induced pulmonary fibrosis
10.3760/cma.j.issn.1001-9391.2016.07.002
- VernacularTitle:TGF-β1/CTGF信号转导通路在百草枯中毒致MRC5细胞损伤中的作用
- Author:
Honghui LI
1
;
Qian CAI
;
Yapeng WANG
;
Herong LIU
;
Min HUANG
Author Information
1. 750004 银川,宁夏医科大公共卫生学院,劳动卫生与职业病教研室/分子毒理学实验室
- Keywords:
Paraquat;
Pulmonary fibrosis;
Transforming grouth factor beta;
Connective tissue growth factor;
Signal transduction
- From:
Chinese Journal of Industrial Hygiene and Occupational Diseases
2016;34(7):484-488
- CountryChina
- Language:Chinese
-
Abstract:
Objective To investigate the effects of Paraquat on human embryonic lung fibroblasts (MRC5) and explore the role of transforming growth factor-β1/connective tissue growth factor signaling pathway in paraquat-induced pulmonary fibrosis.Methods MRC5 cells were cultured with different concentration of PQ (0,12.5,25,50,100,200,400 μ mol/L) for 24 h.The viability of cells was measured by MTT.The protein level of TGF-β1 were analyzed by ELISA after PQ treatment (0,25,50,I00 μmol/L).To examine whether TGF-β1/CTGF signaling pathway was involved in paraquat-induced cytotoxicity,cells was divided into 6 groups:(1) control;(2) 25 μ mol/L PQ group;(3) 50 μ mol/L PQ group;(4) 100 μmol/L PQ group;(5) TGF-β1 positive control group (50 μmol/L rhTGF-β1);(6)stimulate group (100 μmol/L PQ+50 μ mol/L TGF-β1).The protein levels of p-Smad2,p-Smad3 and CTGF were assayed by western blot.The mRNA level of CTGF was assayed by real time RT-PCR.Results MTT showed that cell viability decreased with increasing PQ concentration (P＜0.05).The protein expression of TGF-β1 treated with PQ (25,50,100 μmol/L) significantly increased compared with control in a dose-independent manner(P＜0.05).Exposure to PQ (25,50,100 μmol/L) induced increase of protein levels of p-Smad2 and p-Smad3.Noteworthy,the expression of p-Smad2 and p-Smad3 were dramatically increased following PQ plus TGF-β1 stimulation (P＜0.05).Exposure to PQ (50,100 μmol/L) induced increase of CTGF protein expression and similar greatly increase following PQ plus TGF-β1 stimulation (P＜0.05).Real time RT-PCR showed CTGF mRNA in all groups also significantly up-regulated compared with control (P＜0.05).Conclusion TGF-β1 regulates the expression of target gene CTGF to exhibit its profibrogenic effects by activating TGF-β1/Smad signaling pathway in PQ-induced pulmonary fibrosis.
