title: Switching from astrocytic neuroprotection to neurodegeneration by cytokine stimulation.
abstract: Astrocytes, the largest cell population in the human brain, are powerful inflammatory effectors. Several studies have examined the interaction of activated astrocytes with neurons, but little is known yet about human neurotoxicity under such situations and about strategies of neuronal rescue. To address this question, immortalized murine astrocytes (IMA) were combined with human LUHMES neurons and stimulated with an inflammatory (TNF, IL-1) cytokine mix (CM). Neurotoxicity was studied both in co-cultures and in monocultures after transfer of conditioned medium from activated IMA. Interventions with >20 drugs were used to profile the model system. Control IMA supported neurons and protected them from neurotoxicants. Inflammatory activation reduced this protection, and prolonged exposure of co-cultures to CM triggered neurotoxicity. Neither the added cytokines nor the release of NO from astrocytes were involved in this neurodegeneration. The neurotoxicity-mediating effect of IMA was faithfully reproduced by human astrocytes. Moreover, glia-dependent toxicity was also observed, when IMA cultures were stimulated with CM, and the culture medium was transferred to neurons. Such neurotoxicity was prevented when astrocytes were treated by p38 kinase inhibitors or dexamethasone, whereas such compounds had no effect when added to neurons. Conversely, treatment of neurons with five different drugs, including resveratrol and CEP1347, prevented toxicity of astrocyte supernatants. Thus, the sequential IMA-LUHMES neuroinflammation model is suitable for separate profiling of both glial-directed and directly neuroprotective strategies. Moreover, direct evaluation in co-cultures of the same cells allows for testing of therapeutic effectiveness in more complex settings, in which astrocytes affect pharmacological properties of neurons.
authors.affiliation: Doerenkamp-Zbinden Chair for In Vitro Toxicology and Biomedicine, University of Konstanz, PO Box M657, 78457, Constance, Germany.|Research Training Group 1331 (RTG1331), University of Konstanz, Constance, Germany.
authors.forename: Liudmila
authors.initials: L
authors.lastname: Efremova
authors.affiliation: Doerenkamp-Zbinden Chair for In Vitro Toxicology and Biomedicine, University of Konstanz, PO Box M657, 78457, Constance, Germany.|Konstanz Research School Chemical Biology, University of Konstanz, Constance, Germany.
authors.forename: Petra
authors.initials: P
authors.lastname: Chovancova
authors.affiliation: Doerenkamp-Zbinden Chair for In Vitro Toxicology and Biomedicine, University of Konstanz, PO Box M657, 78457, Constance, Germany.
authors.forename: Martina
authors.initials: M
authors.lastname: Adam
authors.affiliation: Doerenkamp-Zbinden Chair for In Vitro Toxicology and Biomedicine, University of Konstanz, PO Box M657, 78457, Constance, Germany.|Research Training Group 1331 (RTG1331), University of Konstanz, Constance, Germany.
authors.forename: Simon
authors.initials: S
authors.lastname: Gutbier
authors.affiliation: Doerenkamp-Zbinden Chair for In Vitro Toxicology and Biomedicine, University of Konstanz, PO Box M657, 78457, Constance, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Schildknecht
authors.affiliation: Doerenkamp-Zbinden Chair for In Vitro Toxicology and Biomedicine, University of Konstanz, PO Box M657, 78457, Constance, Germany. marcel.leist@uni-konstanz.de.
authors.forename: Marcel
authors.initials: M
authors.lastname: Leist
mesh_terms: D000818:Animals; D000893:Anti-Inflammatory Agents / Q000737:chemistry / Q000494:pharmacology; D001253:Astrocytes / Q000166:cytology / Q000187:drug effects* / Q000276:immunology / Q000378:metabolism; D002450:Cell Communication / Q000187:drug effects*; D002461:Cell Line, Transformed; D002470:Cell Survival / Q000187:drug effects; D018920:Coculture Techniques; D016207:Cytokines / Q000819:agonists* / Q000037:antagonists & inhibitors / Q000378:metabolism; D003907:Dexamethasone / Q000037:antagonists & inhibitors / Q000494:pharmacology; D006727:Hormone Antagonists / Q000494:pharmacology; D006801:Humans; D053583:Interleukin-1beta / Q000819:agonists / Q000037:antagonists & inhibitors / Q000378:metabolism; D020935:MAP Kinase Signaling System / Q000187:drug effects; D051379:Mice; D015735:Mifepristone / Q000494:pharmacology; D055495:Neurogenesis / Q000187:drug effects; D009473:Neuronal Plasticity / Q000187:drug effects; D009474:Neurons / Q000166:cytology / Q000187:drug effects* / Q000276:immunology / Q000378:metabolism; D018696:Neuroprotective Agents / Q000494:pharmacology*; D009498:Neurotoxins / Q000037:antagonists & inhibitors / Q000633:toxicity*; D047428:Protein Kinase Inhibitors / Q000494:pharmacology; D014409:Tumor Necrosis Factor-alpha / Q000819:agonists / Q000037:antagonists & inhibitors / Q000378:metabolism
chemical_list: D000893:Anti-Inflammatory Agents; D016207:Cytokines; D006727:Hormone Antagonists; D053583:Interleukin-1beta; D018696:Neuroprotective Agents; D009498:Neurotoxins; D047428:Protein Kinase Inhibitors; D014409:Tumor Necrosis Factor-alpha; D015735:Mifepristone; D003907:Dexamethasone
keywords: Astrocyte; LUHMES; Neuroinflammation; Neuropharmacology; p38 kinase