title: Simvastatin protects against amyloid beta and HIV-1 Tat-induced promoter activities of inflammatory genes in brain endothelial cells.
abstract: Increased deposition of amyloid beta (Abeta) is characteristic for normal aging and human immunodeficiency virus-1 (HIV-1)-associated alterations of the central nervous system. In addition, both Abeta and HIV-1 are known to induce cellular oxidative stress and disruption of the blood-brain barrier (BBB). Therefore, we hypothesize that Abeta and HIV-1 protein Tat can potentiate their proinflammatory effects at the brain endothelium level. To address this hypothesis, we studied promoter activity of three proinflammatory genes in an in vitro BBB model of human brain microvascular endothelial cells (HBMEC) cocultured with a human astrocyte cell line producing Tat (SVGA-Tat cells) and exposed to Abeta. Treatment of HBMEC with Abeta(1-40) in the presence of SVGA-Tat cells resulted in a significant up-regulation of E-selectin, CC chemokine ligand-2, and interleukin-6 promoter activities and protein levels compared with the individual effects of Abeta or Tat. In addition, Abeta markedly amplified E-selectin promoter activity in HBMEC cocultured with HIV-1-infected Jurkat T cells. Simvastatin, the 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor, effectively blocked proinflammatory reactions induced by Abeta in cocultures with SVGA-Tat cells or with HIV-1-infected Jurkat cells. The present study indicates that a combined exposure to Abeta and Tat or HIV-1 can synergistically potentiate the expression of inflammatory genes in brain endothelial cells. In addition, simvastatin may provide a beneficial influence by reducing these effects at the BBB level.
authors.affiliation: Molecular Neuroscience and Vascular Biology Laboratory, Department of Neurosurgery, University of Kentucky Medical Center, 593 Wethington Bldg., 900 S Limestone, Lexington, KY 40536, USA.
authors.forename: Ibolya E
authors.initials: IE
authors.lastname: András
authors.forename: Geunbae
authors.initials: G
authors.lastname: Rha
authors.forename: Wen
authors.initials: W
authors.lastname: Huang
authors.forename: Sungyong
authors.initials: S
authors.lastname: Eum
authors.forename: Pierre-Olivier
authors.initials: PO
authors.lastname: Couraud
authors.forename: Ignacio A
authors.initials: IA
authors.lastname: Romero
authors.forename: Bernhard
authors.initials: B
authors.lastname: Hennig
authors.forename: Michal
authors.initials: M
authors.lastname: Toborek
mesh_terms: D016229:Amyloid beta-Peptides / Q000494:pharmacology*; D000924:Anticholesteremic Agents / Q000494:pharmacology; D001253:Astrocytes / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D001921:Brain / Q000187:drug effects / Q000378:metabolism / Q000473:pathology*; D002461:Cell Line, Transformed; D019610:Cytoprotection / Q000187:drug effects; D042783:Endothelial Cells / Q000187:drug effects / Q000378:metabolism* / Q000473:pathology; D005786:Gene Expression Regulation / Q000187:drug effects*; D015497:HIV-1 / Q000472:pathogenicity / Q000502:physiology; D006801:Humans; D007249:Inflammation / Q000235:genetics; D018836:Inflammation Mediators / Q000378:metabolism; D019169:Jurkat Cells; D010446:Peptide Fragments / Q000494:pharmacology*; D011401:Promoter Regions, Genetic / Q000235:genetics*; D019087:Selectins / Q000235:genetics; D019821:Simvastatin / Q000494:pharmacology*; D015533:Transcriptional Activation / Q000187:drug effects; D054322:tat Gene Products, Human Immunodeficiency Virus / Q000235:genetics / Q000378:metabolism*
chemical_list: D016229:Amyloid beta-Peptides; D000924:Anticholesteremic Agents; D018836:Inflammation Mediators; D010446:Peptide Fragments; D019087:Selectins; C078592:amyloid beta-protein (1-40); D054322:tat Gene Products, Human Immunodeficiency Virus; D019821:Simvastatin