Platelet-activating factor enhances the expression of nerve growth factor in normal human astrocytes under hypoxia

• Published in: Brain research. Molecular brain research. Vol. 133; no. 1; pp. 95 - 101
• Main Authors: Yoshida, Hidemi, Imaizumi, Tadaatsu, Tanji, Kunikazu, Sakaki, Hirotaka, Metoki, Norifumi, Hatakeyama, Masaharu, Yamashita, Koji, Ishikawa, Akira, Taima, Kageaki, Sato, Yoshihiro, Kimura, Hiroto, Satoh, Kei
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 05.01.2005; Elsevier
• Subjects: Astrocytes; Astrocytes - drug effects; Biological and medical sciences; Cell Hypoxia; Cell Survival; Cells, Cultured; Deferoxamine - pharmacology; Desferrioxamine; Diterpenes - pharmacology; Dose-Response Relationship, Drug; Drug Interactions; Enzyme-Linked Immunosorbent Assay - methods; Fundamental and applied biological sciences. Psychology; Gene Expression Regulation - drug effects; Ginkgolides; Glial Fibrillary Acidic Protein - metabolism; Humans; Hypoxia; Iron Chelating Agents - pharmacology; Lactones - pharmacology; Nerve Growth Factors - genetics; Nerve Growth Factors - metabolism; NGF; Platelet Activating Factor - antagonists & inhibitors; Platelet Activating Factor - pharmacology; Platelet-activating factor; Reverse Transcriptase Polymerase Chain Reaction - methods; RNA, Messenger - biosynthesis; Time Factors; Vertebrates: nervous system and sense organs; Desferrioxamine; Disorders of the nervous system; Hypoxia; NGF; Astrocytes; Platelet-activating factor; Human; Oxygen; Neuroglia; Nerve growth factor; Astrocyte; Platelet activating factor; Deferoxamine
• ISSN: 0169-328X; 1872-6941
• DOI: 10.1016/j.molbrainres.2004.09.022

Nerve growth factor (NGF) is required for the survival of neurons. We have addressed the effect of platelet-activating factor (PAF), one of the mediators of ischemic injury of the brain, on NGF expression in astrocytes. Normal human astrocytes in culture were stimulated with PAF, and levels of NGF mRNA and protein were analyzed by reverse transcription-polymerase chain reaction (RT-PCR), real-time quantitative PCR and enzyme-linked immunosorbent assay (ELISA). PAF increased the expressions of NGF mRNA and protein in astrocytes in time- and concentration-dependent manners. After 48-h stimulation, 10 nmol/L PAF increased the levels of NGF protein in astrocyte-conditioned medium by 1.4-fold. The PAF-induced stimulation of NGF expression was further enhanced (2.1-fold of the control) in the cells under hypoxic culture condition. BN52021 (Ginkgolide B), an antagonist for PAF binding sites, suppressed the effect of PAF. We conclude that PAF enhances NGF gene expression in human astrocytes, and the PAF-induced increase in the expression of NGF under hypoxia may benefit the protection of the nervous tissue by promoting neuronal survival.