Role of MAPK signaling pathway in epithelial-mesenchymal transition of type II alveolar epithelial cells induced by Paraquat
10.3760/cma.j.issn.1001-9391.2018.08.001
- VernacularTitle: MAPK信号通路在百草枯诱导上皮-间充质改变中的作用
- Author:
Chendi ZHU
1
;
Muzhen GUO
;
Qian CAI
;
Yingying LI
;
Kexin WU
;
Min HUANG
Author Information
1. School of Public Health, Ningxia Medical University, Yinchuan 750004, China
- Publication Type:Journal Article
- Keywords:
Paraquat;
Pulmondnyalveolar;
Epithelial Cells;
Protein Kinases
- From:
Chinese Journal of Industrial Hygiene and Occupational Diseases
2018;36(8):561-567
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To investigate the roles of p38 mitogen-activated protein kinases (p38 MAPK) , extracellular regulated protein kinases (ERK) and c-Jun N-tenninal kinases (JNK) of MAPK signaling pathway in Paraquat-induced epithelial to mesenchymal transition (EMT) of type II alveolarepithelial cells.
Methods:RLE-6NT cells were incubated with different concentrations of PQ (0, 25, 50, 100μmol/L) for 6, 12 and 24 h. Cell morphology alteration was observed under phase-contrast microscopy. Cell viability was determined using an MTT assay. Cell migration ability was detected using scratch wound assay. Protein expression of P-p38 MAP, P-Erk1/2, P-JNK, E-cad, ZO-1, Vimentin and а-SMA were detected by western blot. The level of genes related to fibrosis (COL-I, COL-III, FN and FSP-1) were analyzed via quantitative real-time RT-PCR.
Results:Cell morphology started to undergo EMT changes with a phenotype characteristic of mesenchymal cells, including an elongated shape and a lack of tight cell-cell adhesions induced by 100μmol/L PQ treatment in a time-dependent manner. MTT showed that cell viability decreased with increasing PQ concentration (50、100、200、300 μmol/L PQ treatment for 24 h) and increasing treatment time (200 μmol/L PQ treatment for 6, 12, 24, 36, 48 h) . Compared to control group, the expressions of the epithelial phenotype marker E-cad and ZO-1 significantly decreased with PQ treatment (50, 100μmol/L) in a time-dependent manner (P<0.05) . Additionally, the level of the mesenchymal marker (a-SMA, vimentin) dramatically increased with PQ treatment in the same concentration-and time-dependent manner (P<0.05) . Cell migration ability was markedly increased after 24 h of 100 μmol/L PQ treatment compared to control (P<0.05) . The phosphorylated forms of p38 MAPK, Erk1/2, and JNK were increased at 24 h after stimulation with PQ (P<0.05) . This PQ induced (100 μmol/L) phosphorylation was markedly attenuated in the presence of the p38 MAPK, ERK and JNK inhibitors (SB-203580, SP-600125 and PD98059) respectively. Furthermore, RT-PCR showed that PQ significantly induced the upregulation expression of COL I and III mRNA, Fn, and FSP-1 mRNA (P<0.05) .
Conclusion:PQ-induced pulmonary fibrosis occurs via EMT, which is mediated by the MAPK pathway.
