Distinct patterns of intracerebral hemorrhage-induced alterations in NF-kappaB subunit, iNOS, and COX-2 expression.
Transcription factor nuclear factor-kappaB (NF-kappaB), plays a key role in regulating inflammation in brain pathologies. The goal of this study was to characterize temporal changes in NF-kappaB activation, NF-kappaB subunit expression, and expression of selected NF-kappaB-regulated gene products [inducible form of nitric oxide synthase (iNOS) and cyclooxygenase-2], at the transcriptional and translational level in the brain after intracerebral hemorrhage (ICH). Employing the intrastriatal injection of autologous blood in rats to model ICH, we demonstrated, using NF-kappaB-DNA binding assay, a robust and prolonged NF-kappaB activation, starting as early as 15 min after the onset of ICH. Consequently, we demonstrated that the mRNA and protein for p50, p52, p65, c-Rel, and RelB NF-kappaB subunits, as well as IkappaBalpha were all up-regulated, with a time course ranging from minutes to days following ICH, depending on the subunit. Using reverse transcription-polymerase chain reaction to analyze mRNA and immunoblotting to analyze protein in ICH-affected tissue, we found robust induction of iNOS at both mRNA and protein levels that followed a time-course similar to changes in p65, p52, and RelB mRNA. Oddly, in contrast to iNOS, cyclooxygenase-2 mRNA and protein following an early transient increase demonstrated significant reduction in response to ICH. In summary, NF-kappaB activation occurs within minutes and persists for at least a week in response to ICH. This reaction utilizes different NF-kappaB regulatory subunits and is associated with the expression of selected target genes.
Zhao
Xiurong
X
Department of Neurology, Stroke Program, University of Texas-Houston Medical School, Houston, Texas 77030, USA.
Zhang
Yujian
Y
Strong
Roger
R
Zhang
Jie
J
Grotta
James C
JC
Aronowski
Jaroslaw
J
D000704:Analysis of Variance; D000818:Animals; D002467:Cell Nucleus / Q000201:enzymology; D002543:Cerebral Hemorrhage / Q000201:enzymology* / Q000503:physiopathology*; D003342:Corpus Striatum / Q000473:pathology; D051546:Cyclooxygenase 2 / Q000235:genetics / Q000378:metabolism*; D003600:Cytosol / Q000201:enzymology; D004195:Disease Models, Animal; D015971:Gene Expression Regulation, Enzymologic / Q000502:physiology*; D008297:Male; D016328:NF-kappa B / Q000235:genetics / Q000378:metabolism*; D009474:Neurons / Q000201:enzymology / Q000648:ultrastructure; D052247:Nitric Oxide Synthase Type II / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods; D013997:Time Factors
D016328:NF-kappa B; D012333:RNA, Messenger; D052247:Nitric Oxide Synthase Type II; D051546:Cyclooxygenase 2