title: Simvastatin Reduces Lipopolysaccharides-Accelerated Cerebral Ischemic Injury via Inhibition of Nuclear Factor-kappa B Activity.
abstract: Preceding infection or inflammation such as bacterial meningitis has been associated with poor outcomes after stroke. Previously, we reported that intracorpus callosum microinjection of lipopolysaccharides (LPS) strongly accelerated the ischemia/reperfusion-evoked brain tissue damage via recruiting inflammatory cells into the ischemic lesion. Simvastatin, 3-hydroxy-3-methylgultaryl (HMG)-CoA reductase inhibitor, has been shown to reduce inflammatory responses in vascular diseases. Thus, we investigated whether simvastatin could reduce the LPS-accelerated ischemic injury. Simvastatin (20 mg/kg) was orally administered to rats prior to cerebral ischemic insults (4 times at 72, 48, 25, and 1-h pre-ischemia). LPS was microinjected into rat corpus callosum 1 day before the ischemic injury. Treatment of simvastatin reduced the LPS-accelerated infarct size by 73%, and decreased the ischemia/reperfusion-induced expressions of pro-inflammatory mediators such as iNOS, COX-2 and IL-1β in LPS-injected rat brains. However, simvastatin did not reduce the infiltration of microglial/macrophageal cells into the LPS-pretreated brain lesion. In vitro migration assay also showed that simvastatin did not inhibit the monocyte chemoattractant protein-1-evoked migration of microglial/macrophageal cells. Instead, simvastatin inhibited the nuclear translocation of NF-κB, a key signaling event in expressions of various proinflammatory mediators, by decreasing the degradation of IκB. The present results indicate that simvastatin may be beneficial particularly to the accelerated cerebral ischemic injury under inflammatory or infectious conditions.
authors.affiliation: Department of Neuroscience, Korea University College of Medicine, Seoul 06014, Republic of Korea.
authors.forename: Angela M A
authors.initials: AM
authors.lastname: Anthony Jalin
authors.affiliation: Department of Neurobiology, School of Medicine, Kangwon National University, Chuncheon 24341, Republic of Korea.
authors.forename: Jae-Chul
authors.initials: JC
authors.lastname: Lee
authors.affiliation: Department of Neuroscience, Korea University College of Medicine, Seoul 06014, Republic of Korea.
authors.forename: Geum-Sil
authors.initials: GS
authors.lastname: Cho
authors.affiliation: Department of Nursing, Kyungdong University, Wonju 26495, Republic of Korea.
authors.forename: Chunsook
authors.initials: C
authors.lastname: Kim
authors.affiliation: Department of Neuroscience, Korea University College of Medicine, Seoul 06014, Republic of Korea.
authors.forename: Chung
authors.initials: C
authors.lastname: Ju
authors.affiliation: Department of Neuroscience, Korea University College of Medicine, Seoul 06014, Republic of Korea.
authors.forename: Kisoo
authors.initials: K
authors.lastname: Pahk
authors.affiliation: Department of Neuroscience, Korea University College of Medicine, Seoul 06014, Republic of Korea.
authors.forename: Hwa Young
authors.initials: HY
authors.lastname: Song
authors.affiliation: Department of Neuroscience, Korea University College of Medicine, Seoul 06014, Republic of Korea.
authors.forename: Won-Ki
authors.initials: WK
authors.lastname: Kim
keywords: Cerebral Stroke; Cytokine; Inflammation; Macrophages; Microglia; Simvastatin