Upregulation of vascular endothelial growth factor by heat-killed Listeria monocytogenes in macrophages.
We investigated the effect of heat-killed Listeria monocytogenes (HKLM) on the expression of vascular endothelial growth factor (VEGF) in RAW264.7 macrophage-like cells. The expression of VEGF was induced in RAW264.7 cells treated with HKLM. Pretreatment of cells with cycloheximide, a protein synthesis inhibitor, inhibited the induction of VEGF mRNA by HKLM. Induction of VEGF by HKLM was partially inhibited by treatment of cells with SB203580, a p38 mitogen-activated protein kinase (MAPK) inhibitor, or a neutralizing antibody against tumor necrosis factor-alpha (TNF-alpha). In addition, HKLM induced phosphorylation of p38 MAPK. These results suggest that p38 MAPK and TNF-alpha are involved in the VEGF expression induced by HKLM in RAW264.7 cells. We confirmed that increased VEGF expression is immunohistochemically detected in splenic macrophages of mice infected with L. monocytogenes (L. monocytogenes). VEGF is thought to be involved in inflammatory reactions induced by L. monocytogenes infection.
Sato
Fuyuki
F
Department of Pathology, Hirosaki University School of Medicine, Hirosaki 036-8562, Japan. fsato@cc.hirosaki-u.ac.jp
Imaizumi
Tadaatsu
T
Sashinami
Hiroshi
H
Yoshida
Hidemi
H
Kusumi
Tomomi
T
Mori
Fumiaki
F
Wakabayashi
Koichi
K
Nakane
Akio
A
Satoh
Kei
K
Kijima
Hiroshi
H
D000818:Animals; D002460:Cell Line; D006358:Hot Temperature; D007249:Inflammation / Q000378:metabolism / Q000382:microbiology; D008089:Listeria monocytogenes / Q000502:physiology*; D008264:Macrophages / Q000378:metabolism* / Q000382:microbiology* / Q000473:pathology; D051379:Mice; D015854:Up-Regulation / Q000502:physiology*; D042461:Vascular Endothelial Growth Factor A / Q000096:biosynthesis* / Q000235:genetics / Q000502:physiology
D042461:Vascular Endothelial Growth Factor A; C467480:vascular endothelial growth factor A, mouse