title: Protein Kinase C Epsilon Contributes to NADPH Oxidase Activation in a Pre-Eclampsia Lymphoblast Cell Model.
abstract: Pre-eclampsia is a pregnancy-specific disorder characterised by hypertension and proteinuria, which in severe cases results in multi-system disturbances. The maternal syndrome is associated with a pro-inflammatory state, consisting of leukocyte activation, which is thought to contribute to the widespread endothelial dysfunction. We previously showed increased activation of NADPH oxidase in pre-eclampsia, in both neutrophils and B-lymphoblast cell lines (B-LCLs). In this study, the mechanism by which NADPH oxidase activity is increased in pre-eclampsia was further investigated. NADPH oxidase activity was found to be increased in phorbol-12-myristate-13-acetate (PMA) stimulated B-LCLs isolated from women with pre-eclampsia. This correlated with an increase in protein kinase C (PKC) substrate phosphorylation, p47-phox phosphorylation (a regulatory component of NADPH oxidase) and p47-phox directed-kinase activity. Using ion exchange and hydroxyapatite chromatography we identified a major peak of PMA regulated p47-phox kinase activity. Chromatography fractions were probed for PKC isoforms. We found the major peak of p47-phox kinase activity could not be separated from the elution profile of PKC epsilon. Using a peptide inhibitor of PKC epsilon, PMA-induced reactive oxygen species (ROS) production could be reduced to that of a normal B-LCL. These data suggest a pro-inflammatory role for PKC epsilon in the pathogenesis of pre-eclampsia.
authors.affiliation: Pharmacology and Therapeutics Group, Department of Cardiovascular Sciences, Leicester Royal Infirmary and NIHR Cardiovascular Biomedical Research Unit, Clinical Sciences Building, Leicester, LE2 7LX, UK.
authors.forename: Toryn M
authors.initials: TM
authors.lastname: Poolman
authors.affiliation: Pharmacology and Therapeutics Group, Department of Cardiovascular Sciences, Leicester Royal Infirmary and NIHR Cardiovascular Biomedical Research Unit, Clinical Sciences Building, Leicester, LE2 7LX, UK.
authors.forename: Paulene A
authors.initials: PA
authors.lastname: Quinn
authors.affiliation: Pharmacology and Therapeutics Group, Department of Cardiovascular Sciences, Leicester Royal Infirmary and NIHR Cardiovascular Biomedical Research Unit, Clinical Sciences Building, Leicester, LE2 7LX, UK.
authors.forename: Leong
authors.initials: L
authors.lastname: Ng
keywords: NADPH oxidase; free radicals; hypertension; pre-eclampsia; protein kinase C