title: Similar protective effects of BQ-123 and erythropoietin on survival of neural cells and generation of neurons upon hypoxic injury.
abstract: Our recent study [Danielyan et al., 2005. Eur. J. Cell Biol. 84, 567-579] showed an additive protective effect of endothelin (ET) receptor A (ETA-R) blockade and erythropoietin (EPO) on the survival and rejuvenation of rat astroglial cells exposed to hypoxia. Whether the effects observed with rodent astroglial cells can be reproduced in human astrocytes and whether these effects of ETA-R blockade and EPO on astrocytes are associated with neuronal survival remained open. Therefore, in the present study, the effects of the ETA-R antagonist BQ-123 and EPO on the maintenance of the neuronal population and survival of the human fetal astroglial cell line (SV-FHAS) under normoxic and hypoxic conditions (NC and HC, respectively) were investigated. Rat brain primary cultures exposed to BQ-123 and/or EPO revealed an increase in the number of beta-III tubulin-positive neurons under NC. The hypoxia-caused loss of neurons was abolished by administration of BQ-123 or EPO. Simultaneous application of EPO and BQ-123 led to an additive protective effect on the generation of neurons under NC only. By contrast, BQ-788, the selective ETB-R antagonist, diminished the neuronal population both in NC and HC. Both under NC and HC the number of non-differentiated nestin+/GFAP- neural cells increased upon application of EPO or BQ-123. SV-FHAS responded to BQ-123 or EPO by a decrease in LDH activity in the culture medium under NC (35%) and HC (26% LDH decrease). Concomitant effects of EPO and BQ-123 were illustrated in an additional increase in the survival of human astrocytes (33% under NC and 17% under HC). These data hint at a neuroprotective therapeutic potency of ETA-R blockade, which either alone or in combination with EPO may improve the survival of astroglial and neuronal cells upon hypoxic injury.
authors.affiliation: Division of Clinical Pharmacology, Institute of Pharmacology and Toxicology, University Hospital of Tübingen, Germany. lusine.danielyan@med.uni-tuebingen.de
authors.forename: Lusine
authors.initials: L
authors.lastname: Danielyan
authors.forename: Lars
authors.initials: L
authors.lastname: Mueller
authors.forename: Barbara
authors.initials: B
authors.lastname: Proksch
authors.forename: Daniela
authors.initials: D
authors.lastname: Kabisch
authors.forename: Michael
authors.initials: M
authors.lastname: Weller
authors.forename: Heinrich
authors.initials: H
authors.lastname: Wiesinger
authors.forename: Gayane H
authors.initials: GH
authors.lastname: Buniatian
authors.forename: Christoph H
authors.initials: CH
authors.lastname: Gleiter
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D001253:Astrocytes / Q000378:metabolism*; D001921:Brain / Q000166:cytology; D002448:Cell Adhesion; D018929:Cell Culture Techniques; D015687:Cell Hypoxia / Q000187:drug effects*; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D004921:Erythropoietin / Q000494:pharmacology*; D006801:Humans; D007150:Immunohistochemistry; D018696:Neuroprotective Agents / Q000494:pharmacology*; D010456:Peptides, Cyclic / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar
chemical_list: D018696:Neuroprotective Agents; D010456:Peptides, Cyclic; D004921:Erythropoietin; C072247:cyclo(Trp-Asp-Pro-Val-Leu)