Endothelin-1 Induces Expression of Matrix-associated Genes in Lung Fibroblasts through MEK/ERK

Xu Shi-Wen,Sarah L Howat,Elisabetta A Renzoni,Alan Holmes,Jeremy D Pearson,Michael R Dashwood,George Bou-Gharios,Christopher P Denton,Roland M Du Bois,Carol M Black,Andrew Leask,David J Abraham

doi:10.1074/jbc.m311430200

Abstract

The endothelins are a family of endothelium-derived peptides that possess a variety of biological activities, including potent vasoconstriction. Endothelin-1 (ET-1) is up-regulated during tissue repair and pulmonary fibrosis. Here, we use genome-wide expression array analysis to show that the addition of ET-1 (100 nm, 4 h) to normal lung fibroblasts directly induces expression of matrix and matrix-associated genes, including the profibrotic protein CCN2 (connective tissue growth factor, or CTGF). ET-1 induces the MEK/ERK MAP kinase pathway in fibroblasts. Blockade of the MEK/ERK kinase pathway with U0126 abrogates the ability of ET-1 to induce expression of matrix and matrix-associated mRNAs and the CCN2 protein. The CCN2 promoter possesses an ET-1 response element, which maps to the previously identified basal control element-1 (BCE-1) site. Our results suggest that ET-1 induces a program of matrix synthesis in lung fibroblasts and that ET-1 may play a key role in connective tissue deposition during wound repair and in pulmonary fibrosis.

Highlights

The endothelins are a family of endothelium-derived peptides that possess a variety of biological activities, including potent vasoconstriction
Our results suggest that ET-1 induces a program of matrix synthesis in lung fibroblasts and that ET-1 may play a key role in connective tissue deposition during wound repair and in pulmonary fibrosis
We found that pre-incubation of cells with U0126 potently inhibited the ability of ET-1 to induce matrix metalloproteinase-1 (MMP-1), CCN2, collagen IV, TSP-1, and tissue inhibitor of matrix metalloprotenases-3 (TIMP-3) mRNA expression

Summary

Introduction

The endothelins are a family of endothelium-derived peptides that possess a variety of biological activities, including potent vasoconstriction. We use genome-wide expression array analysis to show that the addition of ET-1 (100 nM, 4 h) to normal lung fibroblasts directly induces expression of matrix and matrix-associated genes, including the profibrotic protein CCN2 (connective tissue growth factor, or CTGF). Our results suggest that ET-1 induces a program of matrix synthesis in lung fibroblasts and that ET-1 may play a key role in connective tissue deposition during wound repair and in pulmonary fibrosis. As a response to environmental insults or a consequence of local inflammatory processes, structural damage to tissue can occur, triggering a wound-healing response This response consists of an integrated series of biochemical, immunological, and structural changes that result in the de novo synthesis of a new epithelium, blood vessels, and connective tissue [1]. Our results provide new insights into ET-1 biology and suggest a role for ET-1 in enhancing matrix expression and organization during tissue repair and fibrogenesis

Methods

Results

Conclusion