Expression of Enzymes Involved in the Prostanoid Metabolism by Cortical Astrocytes after LPS- induced Inflammation Sonja Johann & Eric Kampmann & Bernd Denecke & Susanne Arnold & Markus Kipp & Jörg Mey & Cordian Beyer Received: 20 November 2007 / Accepted: 4 December 2007 / Published online: 3 January 2008 # Humana Press Inc. 2007 Abstract Neuroinflammatory processes are a common epiphenomenon for a number of neurological and neurode- generative diseases. Besides microglia, astrocytes are implicated in brain inflammation in response to harmful stimuli and pathological processes. Bacterial endotoxins can induce the synthesis and release of proinflammatory mediators, i.e., cytokines and chemokines, by astroglia. In this study, we have investigated the effect of lipopolysac- charide (LPS) treatment on the expression of enzymes of prostanoid synthesis and degradation in cultured mouse cortical astrocytes using an Affymetrix Gene Chip array, quantitative reverse transcriptase polymerase chain reaction (RT-PCR), and an enzyme-immunosorbent assay. LPS treatment induced an upregulation of enzymes responsible for prostaglandin E 2 synthesis, a downregulation of enzymes that catalyzes prostaglandin E 2 (PGE 2 ) degrada- tion and production of proinflammatory leukotrienes. Changes in enzyme expression were accompanied by a highly significant increase in extracellular PGE 2 . Our data demonstrate that astrocytes are directly involved in the complex regulation of proinflammatory prostanoids in the CNS under pathological processes, thus being of potential interest as targets for therapeutical interventions. Further studies are required to unravel the different roles and interactions between astroglia and other cells of the brain- intrinsic innate immune system during inflammation. Keywords Astroglia . Cortex . Prostanoid metabolism . Dexamethasone . PGE 2 . Neuro-inflammation Abbreviations AA arachidonic acid ALOX-5 5-lipoxygenase CNS central nervous system COX cyclooxygenase DEX dexamethasone DNA deoxyribonucleic acid EDTA ethylenediamine tetraacetic acid EIA enzyme immunosorbent assay GFAP glial fibrillary acidic protein HPGD 15-hydroxy prostaglandin dehydrogenase HPLC high-performance liquid chromatography HPRT hypoxanthin-guanin-phosphoribosyl-transferase IL interleukin LBP lipopolysaccharide binding protein LPS lipopolysaccharides LTB leukotrienes Myd88 myeloid differentiation factor 88 NS-398 N-(2-cyclohexyloxy-4-nitrophenyl)- methanesulfonamide OD optical density J Mol Neurosci (2008) 34:177–185 DOI 10.1007/s12031-007-9028-4 Sonja Johann and Eric Kampmann contributed equally. S. Johann : S. Arnold : M. Kipp : C. Beyer (*) Institute of Neuroanatomy, Medical Clinic, RWTH, Aachen, Germany e-mail: cbeyer@ukaachen.de E. Kampmann : J. Mey Institute of Biology II, RWTH, Aachen, Germany B. Denecke Interdisciplinary Center for Clinical Research (IZKF) “BIOMAT”, RWTH, Aachen, Germany C. Beyer Institut für Neuroanatomie, Universitätsklinikum/RWTH Aachen, Wendlingweg 2, 52074 Aachen, Germany