title: Inhibition of connective tissue growth factor attenuates paraquat-induced lung fibrosis in a human MRC-5 cell line.
abstract: Chronic exposure to Paraquat (PQ) may result in progressive pulmonary fibrosis and subsequent chronic obstructive pulmonary malfunction. Connective tissue growth factor (CTGF) has been proposed as a key determinant in the development of lung fibrosis. We investigated thus whether knock down of CTGF can prevent human lung fibroblasts (MRC-5) activation and proliferation with the subsequent inhibition of PQ-induced fibrosis. MRC-5 was transfected with CTGF-siRNAs and exposed to different concentrations of PQ. The siRNA-silencing efficacy was evaluated using western blotting analyses, qRT-PCR and flow cytometry. Next, the viability and migration of MRC-5 was determined. MMP-2, MMP-9, and TIMP-1 accumulation were quantified to evaluate the lung fibrosis exposure to PQ. Over expression of CTGF mRNA was observed in human MRC-5 cell as early as 6 h following PQ stimulation. CTGF gene expression in MRC-5 cells was substantially reduced by RNAi, which significantly suppressed the expression of the lung fibrosis markers such as tissue inhibitor of metalloproteinase-2 (TIMP-2), Matrix metalloproteinase-2 (MMP-2) and Matrix metalloproteinase-9 (MMP-9) that were stimulated by PQ. Inhibition of CTGF expression suppressed impeded the proliferation and migration ability of MRC-5 cells and resulted in cell-extracellular matrix (ECM) protein accumulation in cells. Our results suggest that CTGF promoted the development of PQ-induced lung fibrosis in collaboration with transforming growth factor β1 (TGFβ1). Furthermore, the observed arresting effects of CTGF knock down during this process suggested that CTGF is the potential target site for preventing PQ-induced pulmonary fibrosis. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1620-1626, 2016.
authors.affiliation: The Department of Occupational and Environmental Health, School of Public Health, Ningxia Medical University, 750004, 1160 Shengli Street, Xingqing District, Yinchuan, 750004, People's Republic of China.
authors.forename: Min
authors.initials: M
authors.lastname: Huang
authors.affiliation: The Department of Occupational and Environmental Health, School of Public Health, Ningxia Medical University, 750004, 1160 Shengli Street, Xingqing District, Yinchuan, 750004, People's Republic of China.
authors.forename: Huifang
authors.initials: H
authors.lastname: Yang
authors.affiliation: The Department of Occupational and Environmental Health, School of Public Health, Ningxia Medical University, 750004, 1160 Shengli Street, Xingqing District, Yinchuan, 750004, People's Republic of China.
authors.forename: Lingqin
authors.initials: L
authors.lastname: Zhu
authors.affiliation: The Department of Occupational and Environmental Health, School of Public Health, Ningxia Medical University, 750004, 1160 Shengli Street, Xingqing District, Yinchuan, 750004, People's Republic of China.
authors.forename: Honghui
authors.initials: H
authors.lastname: Li
authors.affiliation: The Department of Occupational and Environmental Health, School of Public Health, Ningxia Medical University, 750004, 1160 Shengli Street, Xingqing District, Yinchuan, 750004, People's Republic of China.
authors.forename: Jian
authors.initials: J
authors.lastname: Zhou
authors.affiliation: School of Public Health, Key Lab of Public Health Safety, Ministry of Education, WHO Collaborating Center for Occupational Health, Fudan University, Shanghai, 200032, China. zhijunzhou@ubc-mc.org.
authors.forename: Zhijun
authors.initials: Z
authors.lastname: Zhou
mesh_terms: D002460:Cell Line; D055513:Connective Tissue Growth Factor / Q000037:antagonists & inhibitors* / Q000235:genetics; D006801:Humans; D020778:Matrix Metalloproteinase 2 / Q000032:analysis; D020780:Matrix Metalloproteinase 9 / Q000032:analysis; D010269:Paraquat / Q000633:toxicity*; D011658:Pulmonary Fibrosis / Q000139:chemically induced* / Q000188:drug therapy / Q000378:metabolism; D034741:RNA, Small Interfering / Q000235:genetics; D019715:Tissue Inhibitor of Metalloproteinase-1 / Q000032:analysis; D019716:Tissue Inhibitor of Metalloproteinase-2 / Q000032:analysis
chemical_list: D034741:RNA, Small Interfering; C560822:TIMP1 protein, human; C560823:TIMP2 protein, human; D019715:Tissue Inhibitor of Metalloproteinase-1; D019716:Tissue Inhibitor of Metalloproteinase-2; D055513:Connective Tissue Growth Factor; D020778:Matrix Metalloproteinase 2; D020780:Matrix Metalloproteinase 9; D010269:Paraquat
keywords: Paraquat; connective tissue growth factor; siRNA; transforming growth factor β1