Pediatr Allergy Respir Dis.  2010 Jun;20(2):100-106.

Induction of Vascular Endothelial Growth Factor Protein by Mycoplasma pneumoniae

• Lee KE
• Hong JY
• Sohn MH
• Kim KW
• Park ID
• Chang MW
• Kim KE

Abstract

PURPOSE
Mycoplasma pneumoniae is an extracellular pathogen that attaches to and destroys the ciliated epithelial cells of the respiratory tract. The vascular endothelial growth factor (VEGF) is a critical angiogenic factor that manages the formation and function of vascular networks. Thus, we examined whether M. pneumoniae lysate (MPL) induces VEGF and MPL-induced VEGF expression is regulated by the activation of mitogen-activated protein kinase (MAPK) pathways in airway epithelial cells.
METHODS
Cells were treated with MPL in dose and time dependent manners or pretreated with chemical inhibitors of MAPK signaling molecules before the addition of MPL. The supernatants were measured by a specific human VEGF enzyme-linked immunosorbent assay (ELISA). The RNAs were extracted and synthesized into cDNAs for VEGF gene expression by polymerase chain reaction.
RESULTS
MPL considerably increased VEGF mRNA 2 hours after treatment, which was gradually reduced thereafter. On the other hand, VEGF protein was continuously amplified for 12 hours after both 5 and 10 microg/mL MPL treatment. Pretreatment with U0126 (a specific extracellular signal-regulated kinase inhibitor) and SB202190 (a specific p38 inhibitor) abolished MPL-stimulated VEGF protein close to basal level (-85%), whereas JNK inhibitor II (a specific c-Jun N-terminal kinase inhibitor) partially decreased VEGF protein (57%).
CONCLUSION
We concluded that MPL induces VEGF expression through the activation of MAPK signaling molecules (ERK, p38 and JNK) in airway epithelial cells.

Keyword

Mycoplasma pneumoniae; Vascular endothelial growth factor; Mitogen-activated protein kinase; Airway epithelial cell

MeSH Terms

Angiogenesis Inducing Agents
Butadienes
DNA, Complementary
Enzyme-Linked Immunosorbent Assay
Epithelial Cells
Gene Expression
Hand
Humans
Imidazoles
JNK Mitogen-Activated Protein Kinases
Mycoplasma
Mycoplasma pneumoniae
Nitriles
Phosphotransferases
Pneumonia
Pneumonia, Mycoplasma
Polymerase Chain Reaction
Protein Kinases
Pyridines
Respiratory System
RNA
RNA, Messenger
Vascular Endothelial Growth Factor A
Angiogenesis Inducing Agents
Butadienes
DNA, Complementary
Imidazoles
JNK Mitogen-Activated Protein Kinases
Nitriles
Phosphotransferases
Protein Kinases
Pyridines
RNA
RNA, Messenger
Vascular Endothelial Growth Factor A