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Title: Lipopolysaccharide induces autotaxin expression in human monocytic THP-1 cells

Abstract

Autotaxin (ATX) is a secreted enzyme with lysophospholipase D (lysoPLD) activity, which converts lysophosphatidylcholine (LPC) into lysophosphatidic acid (LPA), a bioactive phospholipid involved in numerous biological activities, including cell proliferation, differentiation, and migration. In the present study, we found that bacterial lipopolysaccharide (LPS), a well-known initiator of the inflammatory response, induced ATX expression in monocytic THP-1 cells. The activation of PKR, JNK, and p38 MAPK was required for the ATX induction. The LPS-induced ATX in THP-1 cells was characterized as the {beta} isoform. In the presence of LPC, ATX could promote the migrations of THP-1 and Jurkat cells, which was inhibited by pertussis toxin (PTX), an inhibitor of Gi-mediated LPA receptor signaling. In summary, LPS induces ATX expression in THP-1 cells via a PKR, JNK and p38 MAPK-mediated mechanism, and the ATX induction is likely to enhance immune cell migration in proinflammatory response by regulating LPA levels in the microenvironment.

Authors:
 [1];  [2]
  1. Key Laboratory for Cell Proliferation and Regulation Biology of Ministry of Education, Institute of Cell Biology, College of Life Sciences, Beijing Normal University, No. 19 Xinjiekouwai Avenue, Beijing 100875 (China)
  2. Key Laboratory for Cell Proliferation and Regulation Biology of Ministry of Education, Institute of Cell Biology, College of Life Sciences, Beijing Normal University, No. 19 Xinjiekouwai Avenue, Beijing 100875 (China), E-mail: jjzhang@bnu.edu.cn
Publication Date:
OSTI Identifier:
21255829
Resource Type:
Journal Article
Resource Relation:
Journal Name: Biochemical and Biophysical Research Communications; Journal Volume: 378; Journal Issue: 2; Other Information: DOI: 10.1016/j.bbrc.2008.11.047; PII: S0006-291X(08)02224-9; Copyright (c) 2008 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
60 APPLIED LIFE SCIENCES; CELL PROLIFERATION; ENZYMES; HUMAN POPULATIONS; INFLAMMATION; PHOSPHOLIPIDS; RECEPTORS; TOXINS

Citation Formats

Li Song, and Zhang Junjie. Lipopolysaccharide induces autotaxin expression in human monocytic THP-1 cells. United States: N. p., 2009. Web.
Li Song, & Zhang Junjie. Lipopolysaccharide induces autotaxin expression in human monocytic THP-1 cells. United States.
Li Song, and Zhang Junjie. Fri . "Lipopolysaccharide induces autotaxin expression in human monocytic THP-1 cells". United States. doi:.
@article{osti_21255829,
title = {Lipopolysaccharide induces autotaxin expression in human monocytic THP-1 cells},
author = {Li Song and Zhang Junjie},
abstractNote = {Autotaxin (ATX) is a secreted enzyme with lysophospholipase D (lysoPLD) activity, which converts lysophosphatidylcholine (LPC) into lysophosphatidic acid (LPA), a bioactive phospholipid involved in numerous biological activities, including cell proliferation, differentiation, and migration. In the present study, we found that bacterial lipopolysaccharide (LPS), a well-known initiator of the inflammatory response, induced ATX expression in monocytic THP-1 cells. The activation of PKR, JNK, and p38 MAPK was required for the ATX induction. The LPS-induced ATX in THP-1 cells was characterized as the {beta} isoform. In the presence of LPC, ATX could promote the migrations of THP-1 and Jurkat cells, which was inhibited by pertussis toxin (PTX), an inhibitor of Gi-mediated LPA receptor signaling. In summary, LPS induces ATX expression in THP-1 cells via a PKR, JNK and p38 MAPK-mediated mechanism, and the ATX induction is likely to enhance immune cell migration in proinflammatory response by regulating LPA levels in the microenvironment.},
doi = {},
journal = {Biochemical and Biophysical Research Communications},
number = 2,
volume = 378,
place = {United States},
year = {Fri Jan 09 00:00:00 EST 2009},
month = {Fri Jan 09 00:00:00 EST 2009}
}
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