title: Early NADPH oxidase-2 activation is crucial in phenylephrine-induced hypertrophy of H9c2 cells.
abstract: Reactive oxygen species (ROS) produced by different NADPH oxidases (NOX) play a role in cardiomyocyte hypertrophy induced by different stimuli, such as angiotensin II and pressure overload. However, the role of the specific NOX isoforms in phenylephrine (PE)-induced cardiomyocyte hypertrophy is unknown. Therefore we aimed to determine the involvement of the NOX isoforms NOX1, NOX2 and NOX4 in PE-induced cardiomyocyte hypertrophy. Hereto rat neonatal cardiomyoblasts (H9c2 cells) were incubated with 100 μM PE to induce hypertrophy after 24 and 48h as determined via cell and nuclear size measurements using digital imaging microscopy, electron microscopy and an automated cell counter. Digital-imaging microscopy further revealed that in contrast to NOX1 and NOX4, NOX2 expression increased significantly up to 4h after PE stimulation, coinciding and co-localizing with ROS production in the cytoplasm as well as the nucleus. Furthermore, inhibition of NOX-mediated ROS production with apocynin, diphenylene iodonium (DPI) or NOX2 docking sequence (Nox2ds)-tat peptide during these first 4h of PE stimulation significantly inhibited PE-induced hypertrophy of H9c2 cells, both after 24 and 48h of PE stimulation. These data show that early NOX2-mediated ROS production is crucial in PE-induced hypertrophy of H9c2 cells.
authors.affiliation: Department of Pathology, VU University Medical Center, Amsterdam, The Netherlands; ICaR-VU, Institute for Cardiovascular Research, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: Nynke E
authors.initials: NE
authors.lastname: Hahn
authors.affiliation: Department of Physiology, VU University Medical Center, Amsterdam, The Netherlands; ICaR-VU, Institute for Cardiovascular Research, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: René J P
authors.initials: RJ
authors.lastname: Musters
authors.affiliation: Department of Pathology, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: Jan M
authors.initials: JM
authors.lastname: Fritz
authors.affiliation: Department of Pharmacology and Chemical Biology, Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, PA, USA.
authors.forename: Patrick J
authors.initials: PJ
authors.lastname: Pagano
authors.affiliation: Department of Cardiac Surgery, VU University Medical Center, Amsterdam, The Netherlands; ICaR-VU, Institute for Cardiovascular Research, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: Alexander B A
authors.initials: AB
authors.lastname: Vonk
authors.affiliation: Department of Physiology, VU University Medical Center, Amsterdam, The Netherlands; ICaR-VU, Institute for Cardiovascular Research, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: Walter J
authors.initials: WJ
authors.lastname: Paulus
authors.affiliation: Department of Cardiology, VU University Medical Center, Amsterdam, The Netherlands; ICaR-VU, Institute for Cardiovascular Research, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: Albert C
authors.initials: AC
authors.lastname: van Rossum
authors.affiliation: Department of Pathology, VU University Medical Center, Amsterdam, The Netherlands; ICaR-VU, Institute for Cardiovascular Research, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: Christof
authors.initials: C
authors.lastname: Meischl
authors.affiliation: Department of Pathology, VU University Medical Center, Amsterdam, The Netherlands; Department of Cardiac Surgery, VU University Medical Center, Amsterdam, The Netherlands; ICaR-VU, Institute for Cardiovascular Research, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: Hans W M
authors.initials: HW
authors.lastname: Niessen
authors.affiliation: Department of Pathology, VU University Medical Center, Amsterdam, The Netherlands; ICaR-VU, Institute for Cardiovascular Research, VU University Medical Center, Amsterdam, The Netherlands. Electronic address: paj.krijnen@vumc.nl.
authors.forename: Paul A J
authors.initials: PA
authors.lastname: Krijnen
mesh_terms: D000098:Acetophenones / Q000494:pharmacology; D000818:Animals; D002460:Cell Line; D004789:Enzyme Activation / Q000187:drug effects; D006984:Hypertrophy / Q000201:enzymology* / Q000378:metabolism / Q000473:pathology; D008562:Membrane Glycoproteins / Q000037:antagonists & inhibitors / Q000378:metabolism*; D009247:NADH, NADPH Oxidoreductases / Q000378:metabolism; D000074624:NADPH Oxidase 1; D000074662:NADPH Oxidase 2; D000074663:NADPH Oxidase 4; D019255:NADPH Oxidases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D009861:Onium Compounds / Q000494:pharmacology; D010656:Phenylephrine / Q000494:pharmacology*; D051381:Rats; D017382:Reactive Oxygen Species / Q000378:metabolism
chemical_list: D000098:Acetophenones; D008562:Membrane Glycoproteins; D009861:Onium Compounds; D017382:Reactive Oxygen Species; D010656:Phenylephrine; C007517:diphenyleneiodonium; C056165:acetovanillone; D009247:NADH, NADPH Oxidoreductases; C500593:Cybb protein, rat; D000074624:NADPH Oxidase 1; D000074662:NADPH Oxidase 2; D000074663:NADPH Oxidase 4; D019255:NADPH Oxidases; C000614712:NOX1 protein, rat; C498911:Nox4 protein, rat
keywords: Cardiomyocyte hypertrophy; NADPH oxidase; NOX2; Phenylephrine