|
|
||||||||
Department of Cell Biology and Molecular Medicine, New Jersey Medical School, University of Medicine and Dentistry of New Jersey, Newark, New Jersey 07103
Vascular endothelial growth factor (VEGF) expression in murine peritoneal macrophages is strongly upregulated by hypoxia via transcriptional and posttranscriptional mechanisms. Interferon-
(IFN-
) with Escherichia coli lipopolysaccharide (LPS) also upregulates expression of VEGF, as well as of the inducible nitric oxide synthase (iNOS). Hypoxia (1% O2) upregulates VEGF expression in macrophages from both wild-type and iNOS knockout mice, indicating that hypoxic upregulation of VEGF is independent of iNOS. However, the iNOS inhibitor aminoguanidine (AG) decreases the VEGF expression induced by LPS/IFN-
, indicating an important role for NO. NO-dependent induction of VEGF is strongly dependent on cell density. LPS/IFN-
treatment induces minimal VEGF protein expression in macrophages cultured at low cell densities (<0.25 x 106 cells/cm2); at higher cell densities (>0.25 x 106 cells/cm2) that lead to conditions of pericellular hypoxia, however, induction of VEGF expression was strong. Transient transfection of RAW 264.7 cells with luciferase reporter constructs of the murine VEGF promoter indicates that both hypoxia and LPS/IFN-
independently induce VEGF promoter activity, irrespective of cell density. Although LPS/IFN-
treatment induces transcriptional activation of the VEGF promoter, significant levels of VEGF protein are only expressed by cells at high density under conditions of pericellular hypoxia. This suggests an important regulatory role for hypoxia at the posttranscriptional level. Deletion analysis of the VEGF promoter shows that the hypoxia response element region and its immediate flanking sequences are essential for both hypoxia and LPS/IFN-
-induced VEGF promoter activation.
Key Words: macrophages nitric oxide hypoxia vascular endothelial growth factor cellular activation
This article has been cited by other articles:
![]() |
A. Shibata, K. Nakagawa, P. Sookwong, T. Tsuduki, S. Tomita, H. Shirakawa, M. Komai, and T. Miyazawa Tocotrienol Inhibits Secretion of Angiogenic Factors from Human Colorectal Adenocarcinoma Cells by Suppressing Hypoxia-Inducible Factor-1{alpha} J. Nutr., November 1, 2008; 138(11): 2136 - 2142. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. Macedo, G. Pinhal-Enfield, V. Alshits, G. Elson, B. N. Cronstein, and S. J. Leibovich Wound Healing Is Impaired in MyD88-Deficient Mice: A Role for MyD88 in the Regulation of Wound Healing by Adenosine A2A Receptors Am. J. Pathol., December 1, 2007; 171(6): 1774 - 1788. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Ramanathan, G. Pinhal-Enfield, I. Hao, and S. J. Leibovich Synergistic Up-Regulation of Vascular Endothelial Growth Factor (VEGF) Expression in Macrophages by Adenosine A2A Receptor Agonists and Endotoxin Involves Transcriptional Regulation via the Hypoxia Response Element in the VEGF Promoter Mol. Biol. Cell, January 1, 2007; 18(1): 14 - 23. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. A. Gerber, V. Y. Rybalko, C. E. Bigelow, A. A. Lugade, T. H. Foster, J. G. Frelinger, and E. M. Lord Preferential Attachment of Peritoneal Tumor Metastases to Omental Immune Aggregates and Possible Role of a Unique Vascular Microenvironment in Metastatic Survival and Growth Am. J. Pathol., November 1, 2006; 169(5): 1739 - 1752. [Abstract] [Full Text] [PDF] |
||||
![]() |
V. Bhandari, R. Choo-Wing, S. P. Chapoval, C. G. Lee, C. Tang, Y. K. Kim, B. Ma, P. Baluk, M. I. Lin, D. M. McDonald, et al. Essential role of nitric oxide in VEGF-induced, asthma-like angiogenic, inflammatory, mucus, and physiologic responses in the lung PNAS, July 18, 2006; 103(29): 11021 - 11026. [Abstract] [Full Text] [PDF] |
||||
![]() |
B. Gigante, G. Morlino, M. T. Gentile, M. G. Persico, and S. De Falco Plgf-/-eNos-/- mice show defective angiogenesis associated with increased oxidative stress in response to tissue ischemia FASEB J, May 1, 2006; 20(7): 970 - 972. [Abstract] [Full Text] [PDF] |
||||
![]() |
B. Kim, Q. Tang, P. S. Biswas, J. Xu, R. M. Schiffelers, F. Y. Xie, A. M. Ansari, P. V. Scaria, M. C. Woodle, P. Lu, et al. Inhibition of Ocular Angiogenesis by siRNA Targeting Vascular Endothelial Growth Factor Pathway Genes: Therapeutic Strategy for Herpetic Stromal Keratitis Am. J. Pathol., December 1, 2004; 165(6): 2177 - 2185. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |