Anti-hypertrophic and anti-oxidant effect of beta3-adrenergic stimulation in myocytes requires differential neuronal NOS phosphorylation
| Autor: | Koenraad Vandegaer, Xiaolin Niu, Vabren L. Watts, Oscar H. Cingolani, Gerald A. Rameau, Kathleen L. Gabrielson, David A. Kass, Alice S Ho, Djahida Bedja, Rosa Kim, Brian O'Rourke, Karen L. Miller, Lili A. Barouch, Fernando M. Sepulveda |
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| Jazyk: | angličtina |
| Předmět: |
Male
inorganic chemicals medicine.medical_specialty Immunoprecipitation Stimulation Heart failure Nitric Oxide Synthase Type I 030204 cardiovascular system & hematology Biology Inhibitory postsynaptic potential Polymerase Chain Reaction Antioxidants Article Muscle hypertrophy Contractility Rats Sprague-Dawley 03 medical and health sciences Mice 0302 clinical medicine Internal medicine medicine Myocyte Animals Phosphorylation Molecular Biology Cells Cultured 030304 developmental biology Neuronal nitric oxide synthase chemistry.chemical_classification 0303 health sciences Reactive oxygen species Muscle Cells Beta3-adrenergic receptors Hypertrophy Adrenergic beta-Agonists Cell biology Rats Mice Inbred C57BL Endocrinology chemistry Ethanolamines Receptors Adrenergic beta-3 cardiovascular system Cardiology and Cardiovascular Medicine |
| Zdroj: | Journal of Molecular and Cellular Cardiology. :8-17 |
| ISSN: | 0022-2828 |
| DOI: | 10.1016/j.yjmcc.2013.04.025 |
| Popis: | RationaleStimulation of β3-adrenoreceptors (β3-AR) blunts contractility and improves chronic left ventricular function in hypertrophied and failing hearts in a neuronal nitric oxide synthase (nNOS) dependent manner. nNOS can be regulated by post-translational modification of stimulatory phosphorylation residue Ser1412 and inhibitory residue Ser847. However, the role of phosphorylation of these residues in cardiomyocytes and β3-AR protective signaling has yet to be explored.ObjectiveWe tested the hypothesis that β3-AR regulation of myocyte stress requires changes in nNOS activation mediated by differential nNOS phosphorylation.Methods and resultsEndothelin (ET-1) or norepinephrine induced hypertrophy in rat neonatal ventricular cardiomyocytes (NRVMs) was accompanied by increased β3-AR gene expression. Co-administration of the β3-AR agonist BRL-37433 (BRL) reduced cell size and reactive oxygen species (ROS) generation, while augmenting NOS activity. BRL-dependent augmentation of NOS activity and ROS suppression due to NE were blocked by inhibiting nNOS (L-VNIO). BRL augmented nNOS phosphorylation at Ser1412 and dephosphorylation at Ser847. Cells expressing constitutively dephosphorylated Ser1412A or phosphorylated Ser847D nNOS mutants displayed reduced nNOS activity and a lack of BRL modulation. BRL also failed to depress ROS from NE in cells with nNOS-Ser847D. Inhibiting Akt decreased BRL-induced nNOS-Ser1412 phosphorylation and NOS activation, whereas Gi/o blockade blocked BRL-regulation of both post-translational modifications, preventing enhancement of NOS activity and ROS reduction. BRL resulted in near complete dephosphorylation of Ser847 and a moderate rise in Ser1412 phosphorylation in mouse myocardium exposed to chronic pressure-overload.Conclusionβ3-AR regulates myocardial NOS activity and ROS via activation of nNOS involving reciprocal changes in phosphorylation at two regulatory sites. These data identify a novel and potent anti-oxidant and anti-hypertrophic pathway due to nNOS post-translational modification that is coupled to β3-AR receptor stimulation. |
| Databáze: | OpenAIRE |
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