Pigment epithelium-derived factor induces pro-inflammatory genes in neonatal astrocytes through activation of NF-kappa B and CREB.
Pigment epithelium-derived factor (PEDF) is a potent and broadly acting neurotrophic factor that protects neurons in various types of cultured neurons against glutamate excitotoxicity and induced-apoptosis. Some of the effects of PEDF reflect specific changes in gene expression, mediated via activation of the transcription factor NF-kappa B in neurons. To investigate whether PEDF also modulates gene expression in astrocytes, we employed the use of RT-PCR to analyze the gene expression of certain pro-inflammatory genes and found that genes such as IL-1 beta, IL-6, TNF-alpha, MIP1 alpha, and MIP3 alpha were induced in PEDF-treated cultured neonatal astrocytes, but not in adult astrocytes. Electrophoresis mobility shift assay (EMSA) revealed that a time- and dose-dependent increase of NF-kappa B- and AP-1-DNA binding activity was observed in PEDF-treated neonatal astrocytes. Furthermore, rapid phosphorylation of CREB protein had occurred in PEDF-treated neonatal astrocytes. Upregulation of pro-inflammatory and AP-1-related genes by PEDF was blocked by overexpression of dominant negative CREB or a mutated form of I kappa B alpha. These results suggest that the induction of pro-inflammatory genes is mediated via activation of NF-kappa B, AP-1, and CREB in neonatal astrocytes. Taken together, these results demonstrate that PEDF is a multipotent factor, capable of affecting not only neurons, but also neonatal astrocytes, and suggests that it may act as a neuroimmune modulator in the developmental brain.
Yabe
Takeshi
T
Kitasato Institute for Life Sciences, Kitasato University, Tokyo 108-8641, Japan. tyabe@lisci.kitasato-u.ac.jp
Sanagi
Tomomi
T
Schwartz
Joan P
JP
Yamada
Haruki
H
D000818:Animals; D000831:Animals, Newborn; D001253:Astrocytes / Q000187:drug effects / Q000276:immunology / Q000378:metabolism*; D001921:Brain / Q000166:cytology / Q000254:growth & development* / Q000276:immunology; D002478:Cells, Cultured; D018925:Chemokines / Q000235:genetics / Q000276:immunology; D017362:Cyclic AMP Response Element-Binding Protein / Q000187:drug effects / Q000378:metabolism; D016207:Cytokines / Q000187:drug effects / Q000235:genetics; D004268:DNA-Binding Proteins / Q000187:drug effects / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D005136:Eye Proteins / Q000494:pharmacology / Q000502:physiology*; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects / Q000276:immunology*; D020672:I-kappa B Proteins / Q000187:drug effects / Q000378:metabolism; D007155:Immunologic Factors / Q000378:metabolism* / Q000494:pharmacology; D018836:Inflammation Mediators / Q000276:immunology / Q000378:metabolism*; D000072000:NF-KappaB Inhibitor alpha; D016328:NF-kappa B / Q000187:drug effects / Q000378:metabolism; D009414:Nerve Growth Factors / Q000494:pharmacology / Q000502:physiology*; D015213:Neuroimmunomodulation / Q000187:drug effects / Q000235:genetics; D010766:Phosphorylation / Q000187:drug effects; D051381:Rats; D017208:Rats, Wistar; D015843:Serpins / Q000494:pharmacology / Q000502:physiology*; D018808:Transcription Factor AP-1 / Q000187:drug effects / Q000378:metabolism; D015533:Transcriptional Activation / Q000187:drug effects / Q000276:immunology; D015854:Up-Regulation / Q000187:drug effects / Q000276:immunology; D000099174:Pigment Epithelium-Derived Factor
D018925:Chemokines; D017362:Cyclic AMP Response Element-Binding Protein; D016207:Cytokines; D004268:DNA-Binding Proteins; D005136:Eye Proteins; D020672:I-kappa B Proteins; D007155:Immunologic Factors; D018836:Inflammation Mediators; D000072000:NF-KappaB Inhibitor alpha; D016328:NF-kappa B; D009414:Nerve Growth Factors; D015843:Serpins; D018808:Transcription Factor AP-1; D000099174:Pigment Epithelium-Derived Factor; C000606206:Nfkbia protein, rat