| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
RECEPTORS AND SIGNAL TRANSDUCTION
by extracellular pressure mediates the stimulation of macrophage phagocytosis by pressure
Department of Surgery, School of Medicine, Wayne State University and John D. Dingell Veterans Affairs Medical Center, Detroit, Michigan
Submitted 9 November 2004 ; accepted in final form 27 December 2004
We have previously demonstrated that constant 20 mmHg extracellular pressure increases serum-opsonized latex bead phagocytosis by phorbol 12-myristate 13-acetate (PMA)- differentiated THP-1 macrophages in part by inhibiting focal adhesion kinase (FAK) and extracellular signal-regulated kinase (ERK). Because p38 MAPK is activated by physical forces in other cells, we hypothesized that modulation of p38 MAPK might also contribute to the stimulation of macrophage phagocytosis by pressure. We studied phagocytosis in PMA-differentiated THP-1 macrophages, primary human monocytes, and human monocyte-derived macrophages (MDM). p38 MAPK activation was inhibited using SB-203580 or by p38 MAPK
small interfering RNA (siRNA). Pressure increased phagocytosis in primary monocytes and MDM as in THP-1 cells. Increased extracellular pressure for 30 min increased phosphorylated p38 MAPK by 46.4 ± 20.5% in DMSO-treated THP-1 macrophages and by 20.9 ± 9% in primary monocytes (P < 0.05 each). SB-203580 (20 µM) reduced basal p38 MAPK phosphorylation by 34.7 ± 2.1% in THP-1 macrophages and prevented pressure activation of p38. p38 MAPK siRNA reduced total p38 MAPK protein by 50–60%. Neither SB-203580 in THP-1 cells and peripheral monocytes nor p38 MAPK siRNA in THP-1 cells affected basal phagocytosis, but each abolished pressure-stimulated phagocytosis. SB-203580 did not affect basal or pressure-reduced FAK activation in THP-1 macrophages, but significantly attenuated the reduction in ERK phosphorylation associated with pressure. p38 MAPK siRNA reduced total FAK protein by 40–50%, and total ERK by 10–15%, but increased phosphorylated ERK 1.4 ± 0.1-fold. p38 MAPK siRNA transfection did not affect the inhibition of FAK-Y397 phosphorylation by pressure but prevented inhibition of ERK phosphorylation. Changes in extracellular pressure during infection or inflammation regulate macrophage phagocytosis by a FAK-dependent inverse effect on p38 MAPK that might subsequently downregulate ERK.
force; inflammation; infection; leukocyte; mechanotransduction; signal transduction
This article has been cited by other articles:
|
|
 |
|
  H. Shiratsuchi, Y. Kouatli, G. X. Yu, H. M. Marsh, and M. D. Basson Propofol inhibits pressure-stimulated macrophage phagocytosis via the GABAA receptor and dysregulation of p130cas phosphorylation Am J Physiol Cell Physiol, June 1, 2009; 296(6): C1400 - C1410. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. E. Chappell, M. Bunz, E. Smoll, H. Dong, C. Lytle, K. E. Barrett, and D. F. McCole Hydrogen peroxide inhibits Ca2+-dependent chloride secretion across colonic epithelial cells via distinct kinase signaling pathways and ion transport proteins FASEB J, June 1, 2008; 22(6): 2023 - 2036. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 R. J. Anand, S. C. Gribar, J. Li, J. W. Kohler, M. F. Branca, T. Dubowski, C. P. Sodhi, and D. J. Hackam Hypoxia causes an increase in phagocytosis by macrophages in a HIF-1{alpha}-dependent manner J. Leukoc. Biol., November 1, 2007; 82(5): 1257 - 1265. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 K. Chakrabarty, W. Wu, J. L. Booth, E. S. Duggan, K. M. Coggeshall, and J. P. Metcalf Bacillus anthracis Spores Stimulate Cytokine and Chemokine Innate Immune Responses in Human Alveolar Macrophages through Multiple Mitogen-Activated Protein Kinase Pathways. Infect. Immun., August 1, 2006; 74(8): 4430 - 4438. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |
