title: Regulation of NFkappaB in hepatic ischemic preconditioning.
abstract: BACKGROUND
  The second messengers tyrosine kinase (TK) and protein kinase C (PKC) have been implicated in mediating the cellular signaling cascade during hepatic ischemic preconditioning (IPC). We evaluated the role of TK and PKC on the modulation of the transcription factor nuclear factor kappa B (NFkappaB) and its inhibitor IkappaB alpha during IPC.
  
  
  METHODS
  Yorkshire pigs underwent routine harvest. IPC livers underwent 15 minutes of ischemia and 15 minutes of in situ perfusion before harvest, with or without pretreatment with a TK inhibitor (genistein) or a PKC inhibitor (chelerythrine). During cold storage and reperfusion, tissue extracts were analyzed for IkappaB alpha phosphorylation and NFkappaB levels and for TK and PKC activity by Western blot.
  
  
  RESULTS
  Control pig livers demonstrated no change in the levels of TK, PKC, IkappaB alpha, or NFkappaB before cold ischemia. IPC grafts demonstrated activation of TK and PKC with increased IkappaB alpha phosphorylation and NFkappaB levels before cold ischemia. IPC grafts pretreated with genistein demonstrated inhibition of TK activation but not of PKC activation. Genistein-pretreated grafts also demonstrated inhibition of IkappaB alpha phosphorylation and a lack of NFkappaB translocation to the nucleus throughout the entire experiment. IPC grafts pretreated with chelerythrine demonstrated inhibition of PKC activation but not TK activation. Chelerythrine-pretreated grafts also demonstrated IkappaB alpha phosphorylation before cold ischemia and enhanced nuclear levels of NFkappaB.
  
  
  CONCLUSIONS
  Data suggest that the role of TK in IPC might be mediated in part by NFkappaB, but PKC does not depend on NFkappaB for its effect. Two parallel signaling pathways might explain these data.
authors.affiliation: Department of Surgery, University of Massachusetts Medical School, Worcester, USA.
authors.forename: Rocco
authors.initials: R
authors.lastname: Ricciardi
authors.forename: Shimul A
authors.initials: SA
authors.lastname: Shah
authors.forename: Suzanne M
authors.initials: SM
authors.lastname: Wheeler
authors.forename: Steven H
authors.initials: SH
authors.lastname: Quarfordt
authors.forename: Mark P
authors.initials: MP
authors.lastname: Callery
authors.forename: William C
authors.initials: WC
authors.lastname: Meyers
authors.forename: Ravi S
authors.initials: RS
authors.lastname: Chari
mesh_terms: D000470:Alkaloids; D000818:Animals; D053119:Benzophenanthridines; D004268:DNA-Binding Proteins / Q000502:physiology*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D019833:Genistein / Q000494:pharmacology; D020672:I-kappa B Proteins; D019194:Ischemic Preconditioning; D008099:Liver / Q000098:blood supply* / Q000502:physiology*; D023421:Models, Animal; D000072000:NF-KappaB Inhibitor alpha; D016328:NF-kappa B / Q000502:physiology*; D010617:Phenanthridines / Q000494:pharmacology; D011493:Protein Kinase C / Q000037:antagonists & inhibitors / Q000378:metabolism / Q000502:physiology*; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism / Q000502:physiology*; D015398:Signal Transduction / Q000502:physiology*; D013552:Swine
chemical_list: D000470:Alkaloids; D053119:Benzophenanthridines; D004268:DNA-Binding Proteins; D004791:Enzyme Inhibitors; D020672:I-kappa B Proteins; D016328:NF-kappa B; D010617:Phenanthridines; D000072000:NF-KappaB Inhibitor alpha; D019833:Genistein; C016299:chelerythrine; D011505:Protein-Tyrosine Kinases; D011493:Protein Kinase C