title: Endogenous erythropoietin from astrocyte protects the oligodendrocyte precursor cell against hypoxic and reoxygenation injury.
abstract: The hypoxia-responsive cytokine erythropoietin (EPO) provides neuroprotective effects in the damaged brain during ischemic events and neurodegenerative diseases. The purpose of the present study is to evaluate the EPO/EPO receptor (EPOR) endogenous system between astrocyte and oligodendrocyte precursor cell (OPC) under hypoxia. We report here elevated EPO mRNA levels and protein release in cultured astrocytes following hypoxic stimulation by quantitative RT-PCR and ELISA. Furthermore, the EPOR gene expressions were detected in cultured OPCs as in astrocytes and microglias by quantitative RT-PCR. Cell staining revealed the EPOR expression in OPC. To evaluate the protective effect of endogenous EPO from astrocyte to OPCs, EPO/EPOR signaling was blocked by EPO siRNA or EPOR siRNA gene silencing in in vitro study. The suppression of endogenous EPO production in astrocytes by EPO siRNA decreased the protection to OPCs against hypoxic stress. Furthermore, OPC with EPOR siRNA had less cell survival after hypoxic/reoxygenation injury. This suggested that EPO/EPOR signaling from astrocyte to OPC could prevent OPC damage under hypoxic/reoxygenation condition. Our present finding of an interaction between astrocytes and OPCs may lead to a new therapeutic approach to OPCs for use against cellular stress and injury.
authors.affiliation: Department of Molecular Neurobiology, Nagoya City University Graduate School of Medical Sciences, Mizuho-ku, Nagoya, Japan.
authors.forename: Shin
authors.initials: S
authors.lastname: Kato
authors.forename: Mineyoshi
authors.initials: M
authors.lastname: Aoyama
authors.forename: Hiroki
authors.initials: H
authors.lastname: Kakita
authors.forename: Hideki
authors.initials: H
authors.lastname: Hida
authors.forename: Ineko
authors.initials: I
authors.lastname: Kato
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Ito
authors.forename: Tatenobu
authors.initials: T
authors.lastname: Goto
authors.forename: Mohamed H
authors.initials: MH
authors.lastname: Hussein
authors.forename: Kazunobu
authors.initials: K
authors.lastname: Sawamoto
authors.forename: Hajime
authors.initials: H
authors.lastname: Togari
authors.forename: Kiyofumi
authors.initials: K
authors.lastname: Asai
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D001253:Astrocytes / Q000378:metabolism / Q000502:physiology*; D015687:Cell Hypoxia / Q000235:genetics / Q000502:physiology; D002470:Cell Survival / Q000235:genetics; D019610:Cytoprotection / Q000502:physiology*; D004921:Erythropoietin / Q000235:genetics / Q000502:physiology*; D002534:Hypoxia, Brain / Q000473:pathology* / Q000503:physiopathology / Q000517:prevention & control; D051379:Mice; D008813:Mice, Inbred ICR; D009836:Oligodendroglia / Q000166:cytology* / Q000378:metabolism* / Q000473:pathology; D018384:Oxidative Stress / Q000235:genetics; D061251:Primary Cell Culture; D034741:RNA, Small Interfering / Q000502:physiology; D017467:Receptors, Erythropoietin / Q000235:genetics / Q000502:physiology; D013234:Stem Cells / Q000166:cytology* / Q000378:metabolism* / Q000473:pathology
chemical_list: D034741:RNA, Small Interfering; D017467:Receptors, Erythropoietin; D004921:Erythropoietin