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Khaafi M, Tayarani-Najaran Z, Javadi B. Cinnamaldehyde as a Promising Dietary Phytochemical Against Metabolic Syndrome: A Systematic Review. Mini Rev Med Chem 2024; 24:355-369. [PMID: 37489782 DOI: 10.2174/1389557523666230725113446] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2023] [Revised: 06/21/2023] [Accepted: 06/21/2023] [Indexed: 07/26/2023]
Abstract
BACKGROUND Metabolic syndrome (METS) is a set of unhealthy medical conditions considered essential health problems today. Cinnamaldehyde (CA) is the major phytochemical present in the essential oil of cinnamon and possesses antioxidant, anti-inflammatory, hypoglycemic, and antihyperlipidemic activities. AIM We aim to systematically review the effects of CA in preventing and attenuating METS components. Moreover, the cellular and molecular mechanisms of actions of CA, its pharmacokinetics features, and potential structure-activity relationship (SAR) were also surveyed. METHODS PubMed, Science Direct, Scopus, and Google Scholar were searched to retrieve the relevant papers. RESULTS CA possesses various anti-METS activities, including anti-inflammatory, antioxidant, antidiabetic, antidyslipidemia, antiobesity, and antihypertensive properties. Various molecular mechanisms such as stimulating pancreatic insulin release, exerting an insulinotropic effect, lowering lipid peroxidation as well as pancreatic islet oxidant and inflammatory toxicity, increasing the activities of pancreatic antioxidant enzymes, suppressing pro-inflammatory cytokines production, regulating the molecular signaling pathways of the PPAR-γ and AMPK in preadipocytes and preventing adipocyte differentiation and adipogenesis are involved in these activities. CONCLUSIONS CA would effectively hinder METS; however, no robust clinical data supporting these effects in humans is currently available. Accordingly, conducting clinical trials to evaluate the efficacy, safe dosage, pharmacokinetics characteristics, and possible unwanted effects of CA in humans would be of great importance.
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Affiliation(s)
- Mohaddeseh Khaafi
- Medical Toxicology Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Zahra Tayarani-Najaran
- Targeted Drug Delivery Research Center, Pharmaceutical Technology Institute, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Behjat Javadi
- Department of Traditional Pharmacy, School of Pharmacy, Mashhad University of Medical Sciences, Azadi Square, Pardis University Campus, P.O. Box: 9188617871, Mashhad, Iran
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2
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Golatkar V, Bhatt LK. mAKAPβ signalosome: A potential target for cardiac hypertrophy. Drug Dev Res 2023; 84:1072-1084. [PMID: 37203301 DOI: 10.1002/ddr.22081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Revised: 03/05/2023] [Accepted: 05/06/2023] [Indexed: 05/20/2023]
Abstract
Pathological cardiac hypertrophy is the result of a prolonged increase in the workload of the heart that activates various signaling pathways such as MAPK pathway, PKA-dependent cAMP signaling, and CaN-NFAT signaling pathway which further activates genes for cardiac remodeling. Various signalosomes are present in the heart that regulates the signaling of physiological and pathological cardiac hypertrophy. mAKAPβ is one such scaffold protein that regulates signaling pathways involved in promoting cardiac hypertrophy. It is present in the outer nuclear envelope of the cardiomyocytes, which provides specificity of the target toward the heart. In addition, nuclear translocation of signaling components and transcription factors such as MEF2D, NFATc, and HIF-1α is facilitated due to the localization of mAKAPβ near the nuclear envelope. These factors are required for activation of genes promoting cardiac remodeling. Downregulation of mAKAPβ improves cardiac function and attenuates cardiac hypertrophy which in turn prevents the development of heart failure. Unlike earlier therapies for heart failure, knockout or silencing of mAKAPβ is not associated with side effects because of its high specificity in the striated myocytes. Downregulating expression of mAKAPβ is a favorable therapeutic approach toward attenuating cardiac hypertrophy and hence preventing heart failure. This review discusses mAKAPβ signalosome as a potential target for cardiac hypertrophy intervention.
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Affiliation(s)
- Vaishnavi Golatkar
- Department of Pharmacology, SVKM's Dr. Bhanuben Nanavati College of Pharmacy, Vile Parle (W), Mumbai, India
| | - Lokesh K Bhatt
- Department of Pharmacology, SVKM's Dr. Bhanuben Nanavati College of Pharmacy, Vile Parle (W), Mumbai, India
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3
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Regulation of cardiac function by cAMP nanodomains. Biosci Rep 2023; 43:232544. [PMID: 36749130 PMCID: PMC9970827 DOI: 10.1042/bsr20220953] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 01/29/2023] [Accepted: 02/07/2023] [Indexed: 02/08/2023] Open
Abstract
Cyclic adenosine monophosphate (cAMP) is a diffusible intracellular second messenger that plays a key role in the regulation of cardiac function. In response to the release of catecholamines from sympathetic terminals, cAMP modulates heart rate and the strength of contraction and ease of relaxation of each heartbeat. At the same time, cAMP is involved in the response to a multitude of other hormones and neurotransmitters. A sophisticated network of regulatory mechanisms controls the temporal and spatial propagation of cAMP, resulting in the generation of signaling nanodomains that enable the second messenger to match each extracellular stimulus with the appropriate cellular response. Multiple proteins contribute to this spatiotemporal regulation, including the cAMP-hydrolyzing phosphodiesterases (PDEs). By breaking down cAMP to a different extent at different locations, these enzymes generate subcellular cAMP gradients. As a result, only a subset of the downstream effectors is activated and a specific response is executed. Dysregulation of cAMP compartmentalization has been observed in cardiovascular diseases, highlighting the importance of appropriate control of local cAMP signaling. Current research is unveiling the molecular organization underpinning cAMP compartmentalization, providing original insight into the physiology of cardiac myocytes and the alteration associated with disease, with the potential to uncover novel therapeutic targets. Here, we present an overview of the mechanisms that are currently understood to be involved in generating cAMP nanodomains and we highlight the questions that remain to be answered.
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4
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Turcotte MG, Thakur H, Kapiloff MS, Dodge-Kafka KL. A perinuclear calcium compartment regulates cardiac myocyte hypertrophy. J Mol Cell Cardiol 2022; 172:26-40. [PMID: 35952391 PMCID: PMC9727780 DOI: 10.1016/j.yjmcc.2022.07.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 06/16/2022] [Accepted: 07/18/2022] [Indexed: 12/14/2022]
Abstract
The pleiotropic Ca2+/calmodulin-dependent phosphatase calcineurin is a key regulator of pathological cardiac myocyte hypertrophy. The selective activation of hypertrophic calcineurin signaling under stress conditions has been attributed to compartmentation of Ca2+ signaling in cardiac myocytes. Here, perinuclear signalosomes organized by the scaffold protein muscle A-Kinase Anchoring Protein β (mAKAPβ/AKAP6β) are shown to orchestrate local Ca2+ transients, inducing calcineurin-dependent NFATc nuclear localization and myocyte hypertrophy in response to β-adrenergic receptor activation. Fluorescent biosensors for Ca2+ and calcineurin and protein kinase A (PKA) activity, both diffusely expressed and localized by nesprin-1α to the nuclear envelope, are used to define an autonomous mAKAPβ signaling compartment in adult and neonatal rat ventricular myocytes. Notably, β-adrenergic-stimulated perinuclear Ca2+ and PKA and CaN activity transients depended upon mAKAPβ expression, while Ca2+ elevation and PKA and CaN activity in the cytosol were mAKAPβ independent. Buffering perinuclear cAMP and Ca2+ prevented calcineurin-dependent NFATc nuclear translocation and myocyte hypertrophy, without affecting cardiac myocyte contractility. Additional findings suggest that the perinuclear Ca2+ transients were mediated by signalosome-associated ryanodine receptors regulated by local PKA phosphorylation. These results demonstrate the existence of a functionally independent Ca2+ signaling compartment in the cardiac myocyte regulating hypertrophy and provide a premise for targeting mAKAPβ signalosomes to prevent selectively cardiac hypertrophy in disease.
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Affiliation(s)
- Moriah Gildart Turcotte
- Calhoun Center for Cardiology, University of Connecticut Health Center, Farmington, CT 06030, USA
| | - Hrishikesh Thakur
- Departments of Ophthalmology and Medicine, Stanford Cardiovascular Institute, Stanford University, Palo Alto, CA 94304, USA
| | - Michael S Kapiloff
- Departments of Ophthalmology and Medicine, Stanford Cardiovascular Institute, Stanford University, Palo Alto, CA 94304, USA
| | - Kimberly L Dodge-Kafka
- Calhoun Center for Cardiology, University of Connecticut Health Center, Farmington, CT 06030, USA.
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5
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Abstract
The field of cAMP signaling is witnessing exciting developments with the recognition that cAMP is compartmentalized and that spatial regulation of cAMP is critical for faithful signal coding. This realization has changed our understanding of cAMP signaling from a model in which cAMP connects a receptor at the plasma membrane to an intracellular effector in a linear pathway to a model in which cAMP signals propagate within a complex network of alternative branches and the specific functional outcome strictly depends on local regulation of cAMP levels and on selective activation of a limited number of branches within the network. In this review, we cover some of the early studies and summarize more recent evidence supporting the model of compartmentalized cAMP signaling, and we discuss how this knowledge is starting to provide original mechanistic insight into cell physiology and a novel framework for the identification of disease mechanisms that potentially opens new avenues for therapeutic interventions. SIGNIFICANCE STATEMENT: cAMP mediates the intracellular response to multiple hormones and neurotransmitters. Signal fidelity and accurate coordination of a plethora of different cellular functions is achieved via organization of multiprotein signalosomes and cAMP compartmentalization in subcellular nanodomains. Defining the organization and regulation of subcellular cAMP nanocompartments is necessary if we want to understand the complex functional ramifications of pharmacological treatments that target G protein-coupled receptors and for generating a blueprint that can be used to develop precision medicine interventions.
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Affiliation(s)
- Manuela Zaccolo
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - Anna Zerio
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - Miguel J Lobo
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
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6
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Xia X, Yu CY, Bian M, Sun CB, Tanasa B, Chang KC, Bruffett DM, Thakur H, Shah SH, Knasel C, Cameron EG, Kapiloff MS, Goldberg JL. MEF2 transcription factors differentially contribute to retinal ganglion cell loss after optic nerve injury. PLoS One 2020; 15:e0242884. [PMID: 33315889 PMCID: PMC7735573 DOI: 10.1371/journal.pone.0242884] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Accepted: 11/10/2020] [Indexed: 02/07/2023] Open
Abstract
Loss of retinal ganglion cells (RGCs) in optic neuropathies results in permanent partial or complete blindness. Myocyte enhancer factor 2 (MEF2) transcription factors have been shown to play a pivotal role in neuronal systems, and in particular MEF2A knockout was shown to enhance RGC survival after optic nerve crush injury. Here we expanded these prior data to study bi-allelic, tri-allelic and heterozygous allele deletion. We observed that deletion of all MEF2A, MEF2C, and MEF2D alleles had no effect on RGC survival during development. Our extended experiments suggest that the majority of the neuroprotective effect was conferred by complete deletion of MEF2A but that MEF2D knockout, although not sufficient to increase RGC survival on its own, increased the positive effect of MEF2A knockout. Conversely, MEF2A over-expression in wildtype mice worsened RGC survival after optic nerve crush. Interestingly, MEF2 transcription factors are regulated by post-translational modification, including by calcineurin-catalyzed dephosphorylation of MEF2A Ser-408 known to increase MEF2A-dependent transactivation in neurons. However, neither phospho-mimetic nor phospho-ablative mutation of MEF2A Ser-408 affected the ability of MEF2A to promote RGC death in vivo after optic nerve injury. Together these findings demonstrate that MEF2 gene expression opposes RGC survival following axon injury in a complex hierarchy, and further support the hypothesis that loss of or interference with MEF2A expression might be beneficial for RGC neuroprotection in diseases such as glaucoma and other optic neuropathies.
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Affiliation(s)
- Xin Xia
- Mary M. and Sash A. Spencer Center for Vision Research, Department of Ophthalmology, Byers Eye Institute, Stanford University School of Medicine, Palo Alto, CA, United States of America
| | - Caroline Y. Yu
- Mary M. and Sash A. Spencer Center for Vision Research, Department of Ophthalmology, Byers Eye Institute, Stanford University School of Medicine, Palo Alto, CA, United States of America
| | - Minjuan Bian
- Mary M. and Sash A. Spencer Center for Vision Research, Department of Ophthalmology, Byers Eye Institute, Stanford University School of Medicine, Palo Alto, CA, United States of America
| | - Catalina B. Sun
- Mary M. and Sash A. Spencer Center for Vision Research, Department of Ophthalmology, Byers Eye Institute, Stanford University School of Medicine, Palo Alto, CA, United States of America
| | - Bogdan Tanasa
- Mary M. and Sash A. Spencer Center for Vision Research, Department of Ophthalmology, Byers Eye Institute, Stanford University School of Medicine, Palo Alto, CA, United States of America
| | - Kun-Che Chang
- Mary M. and Sash A. Spencer Center for Vision Research, Department of Ophthalmology, Byers Eye Institute, Stanford University School of Medicine, Palo Alto, CA, United States of America
| | - Dawn M. Bruffett
- Mary M. and Sash A. Spencer Center for Vision Research, Department of Ophthalmology, Byers Eye Institute, Stanford University School of Medicine, Palo Alto, CA, United States of America
| | - Hrishikesh Thakur
- Mary M. and Sash A. Spencer Center for Vision Research, Department of Ophthalmology, Byers Eye Institute, Stanford University School of Medicine, Palo Alto, CA, United States of America
| | - Sahil H. Shah
- Mary M. and Sash A. Spencer Center for Vision Research, Department of Ophthalmology, Byers Eye Institute, Stanford University School of Medicine, Palo Alto, CA, United States of America
| | - Cara Knasel
- Mary M. and Sash A. Spencer Center for Vision Research, Department of Ophthalmology, Byers Eye Institute, Stanford University School of Medicine, Palo Alto, CA, United States of America
| | - Evan G. Cameron
- Mary M. and Sash A. Spencer Center for Vision Research, Department of Ophthalmology, Byers Eye Institute, Stanford University School of Medicine, Palo Alto, CA, United States of America
| | - Michael S. Kapiloff
- Mary M. and Sash A. Spencer Center for Vision Research, Department of Ophthalmology, Byers Eye Institute, Stanford University School of Medicine, Palo Alto, CA, United States of America
- Department of Medicine and Stanford Cardiovascular Institute, Stanford University School of Medicine, Palo Alto, CA, United States of America
- * E-mail: (MSK); (JLG)
| | - Jeffrey L. Goldberg
- Mary M. and Sash A. Spencer Center for Vision Research, Department of Ophthalmology, Byers Eye Institute, Stanford University School of Medicine, Palo Alto, CA, United States of America
- * E-mail: (MSK); (JLG)
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7
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Vergarajauregui S, Becker R, Steffen U, Sharkova M, Esser T, Petzold J, Billing F, Kapiloff MS, Schett G, Thievessen I, Engel FB. AKAP6 orchestrates the nuclear envelope microtubule-organizing center by linking golgi and nucleus via AKAP9. eLife 2020; 9:61669. [PMID: 33295871 PMCID: PMC7725499 DOI: 10.7554/elife.61669] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Accepted: 12/03/2020] [Indexed: 12/31/2022] Open
Abstract
The switch from centrosomal microtubule-organizing centers (MTOCs) to non-centrosomal MTOCs during differentiation is poorly understood. Here, we identify AKAP6 as key component of the nuclear envelope MTOC. In rat cardiomyocytes, AKAP6 anchors centrosomal proteins to the nuclear envelope through its spectrin repeats, acting as an adaptor between nesprin-1α and Pcnt or AKAP9. In addition, AKAP6 and AKAP9 form a protein platform tethering the Golgi to the nucleus. Both Golgi and nuclear envelope exhibit MTOC activity utilizing either AKAP9, or Pcnt-AKAP9, respectively. AKAP6 is also required for formation and activity of the nuclear envelope MTOC in human osteoclasts. Moreover, ectopic expression of AKAP6 in epithelial cells is sufficient to recruit endogenous centrosomal proteins. Finally, AKAP6 is required for cardiomyocyte hypertrophy and osteoclast bone resorption activity. Collectively, we decipher the MTOC at the nuclear envelope as a bi-layered structure generating two pools of microtubules with AKAP6 as a key organizer.
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Affiliation(s)
- Silvia Vergarajauregui
- Experimental Renal and Cardiovascular Research, Department of Nephropathology, Institute of Pathology, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Robert Becker
- Experimental Renal and Cardiovascular Research, Department of Nephropathology, Institute of Pathology, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Ulrike Steffen
- Department of Internal Medicine 3 - Rheumatology and Immunology, Friedrich-Alexander-University Erlangen-Nürnberg (FAU) and Universitätsklinikum Erlangen, Erlangen, Germany
| | - Maria Sharkova
- Experimental Renal and Cardiovascular Research, Department of Nephropathology, Institute of Pathology, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Tilman Esser
- Experimental Renal and Cardiovascular Research, Department of Nephropathology, Institute of Pathology, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Jana Petzold
- Experimental Renal and Cardiovascular Research, Department of Nephropathology, Institute of Pathology, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Florian Billing
- Experimental Renal and Cardiovascular Research, Department of Nephropathology, Institute of Pathology, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Michael S Kapiloff
- Departments of Ophthalmology and Medicine, Stanford Cardiovascular Institute, Stanford University, Palo Alto, United States
| | - George Schett
- Department of Internal Medicine 3 - Rheumatology and Immunology, Friedrich-Alexander-University Erlangen-Nürnberg (FAU) and Universitätsklinikum Erlangen, Erlangen, Germany
| | - Ingo Thievessen
- Department of Physics, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany.,Muscle Research Center Erlangen (MURCE), Erlangen, Germany
| | - Felix B Engel
- Experimental Renal and Cardiovascular Research, Department of Nephropathology, Institute of Pathology, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany.,Muscle Research Center Erlangen (MURCE), Erlangen, Germany
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8
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Dodge-Kafka K, Gildart M, Tokarski K, Kapiloff MS. mAKAPβ signalosomes - A nodal regulator of gene transcription associated with pathological cardiac remodeling. Cell Signal 2019; 63:109357. [PMID: 31299211 PMCID: PMC7197268 DOI: 10.1016/j.cellsig.2019.109357] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Revised: 07/01/2019] [Accepted: 07/05/2019] [Indexed: 12/14/2022]
Abstract
Striated myocytes compose about half of the cells of the heart, while contributing the majority of the heart's mass and volume. In response to increased demands for pumping power, including in diseases of pressure and volume overload, the contractile myocytes undergo non-mitotic growth, resulting in increased heart mass, i.e. cardiac hypertrophy. Myocyte hypertrophy is induced by a change in the gene expression program driven by the altered activity of transcription factors and co-repressor and co-activator chromatin-associated proteins. These gene regulatory proteins are subject to diverse post-translational modifications and serve as nuclear effectors for intracellular signal transduction pathways, including those controlled by cyclic nucleotides and calcium ion. Scaffold proteins contribute to the underlying architecture of intracellular signaling networks by targeting signaling enzymes to discrete intracellular compartments, providing specificity to the regulation of downstream effectors, including those regulating gene expression. Muscle A-kinase anchoring protein β (mAKAPβ) is a well-characterized scaffold protein that contributes to the regulation of pathological cardiac hypertrophy. In this review, we discuss the mechanisms how this prototypical scaffold protein organizes signalosomes responsible for the regulation of class IIa histone deacetylases and cardiac transcription factors such as NFAT, MEF2, and HIF-1α, as well as how this signalosome represents a novel therapeutic target for the prevention or treatment of heart failure.
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Affiliation(s)
- Kimberly Dodge-Kafka
- Calhoun Center for Cardiology, Cardiac Signal Transduction and Cellular Biology Laboratory, University of Connecticut Health Center, Farmington, CT, USA.
| | - Moriah Gildart
- Calhoun Center for Cardiology, Cardiac Signal Transduction and Cellular Biology Laboratory, University of Connecticut Health Center, Farmington, CT, USA
| | - Kristin Tokarski
- Calhoun Center for Cardiology, Cardiac Signal Transduction and Cellular Biology Laboratory, University of Connecticut Health Center, Farmington, CT, USA
| | - Michael S Kapiloff
- Departments of Ophthalmology and Medicine, Stanford Cardiovascular Institute, Stanford University, Palo Alto, CA, USA
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9
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Dietary supplementation with arginine and glutamic acid alters the expression of amino acid transporters in skeletal muscle of growing pigs. Amino Acids 2019; 51:1081-1092. [DOI: 10.1007/s00726-019-02748-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2018] [Accepted: 05/26/2019] [Indexed: 01/06/2023]
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10
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Regulation of Neuronal Survival and Axon Growth by a Perinuclear cAMP Compartment. J Neurosci 2019; 39:5466-5480. [PMID: 31097623 DOI: 10.1523/jneurosci.2752-18.2019] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2018] [Revised: 03/11/2019] [Accepted: 04/10/2019] [Indexed: 12/21/2022] Open
Abstract
cAMP signaling is known to be critical in neuronal survival and axon growth. Increasingly the subcellular compartmentation of cAMP signaling has been appreciated, but outside of dendritic synaptic regulation, few cAMP compartments have been defined in terms of molecular composition or function in neurons. Specificity in cAMP signaling is conferred in large part by A-kinase anchoring proteins (AKAPs) that localize protein kinase A and other signaling enzymes to discrete intracellular compartments. We now reveal that cAMP signaling within a perinuclear neuronal compartment organized by the large multivalent scaffold protein mAKAPα promotes neuronal survival and axon growth. mAKAPα signalosome function is explored using new molecular tools designed to specifically alter local cAMP levels as studied by live-cell FRET imaging. In addition, enhancement of mAKAPα-associated cAMP signaling by isoform-specific displacement of bound phosphodiesterase is demonstrated to increase retinal ganglion cell survival in vivo in mice of both sexes following optic nerve crush injury. These findings define a novel neuronal compartment that confers cAMP regulation of neuroprotection and axon growth and that may be therapeutically targeted in disease.SIGNIFICANCE STATEMENT cAMP is a second messenger responsible for the regulation of diverse cellular processes including neuronal neurite extension and survival following injury. Signal transduction by cAMP is highly compartmentalized in large part because of the formation of discrete, localized multimolecular signaling complexes by A-kinase anchoring proteins. Although the concept of cAMP compartmentation is well established, the function and identity of these compartments remain poorly understood in neurons. In this study, we provide evidence for a neuronal perinuclear cAMP compartment organized by the scaffold protein mAKAPα that is necessary and sufficient for the induction of neurite outgrowth in vitro and for the survival of retinal ganglion cells in vivo following optic nerve injury.
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11
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Gildart M, Kapiloff MS, Dodge-Kafka KL. Calcineurin-AKAP interactions: therapeutic targeting of a pleiotropic enzyme with a little help from its friends. J Physiol 2018; 598:3029-3042. [PMID: 30488951 PMCID: PMC7586300 DOI: 10.1113/jp276756] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Accepted: 11/14/2018] [Indexed: 01/14/2023] Open
Abstract
The ubiquitous Ca2+ /calmodulin-dependent phosphatase calcineurin is a key regulator of pathological cardiac hypertrophy whose therapeutic targeting in heart disease has been elusive due to its role in other essential biological processes. Calcineurin is targeted to diverse intracellular compartments by association with scaffold proteins, including by multivalent A-kinase anchoring proteins (AKAPs) that bind protein kinase A and other important signalling enzymes determining cardiac myocyte function and phenotype. Calcineurin anchoring by AKAPs confers specificity to calcineurin function in the cardiac myocyte. Targeting of calcineurin 'signalosomes' may provide a rationale for inhibiting the phosphatase in disease.
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Affiliation(s)
- Moriah Gildart
- Calhoun Center for Cardiology, University of Connecticut Health Center, Farmington, CT, USA
| | - Michael S Kapiloff
- Departments of Ophthalmology and Cardiovascular Medicine, Byers Eye Institute and Spencer Center for Vision Research, Stanford Cardiovascular Institute, Stanford University, Palo Alto, CA, USA
| | - Kimberly L Dodge-Kafka
- Calhoun Center for Cardiology, University of Connecticut Health Center, Farmington, CT, USA
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12
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Li J, Aponte Paris S, Thakur H, Kapiloff MS, Dodge-Kafka KL. Muscle A-kinase-anchoring protein-β-bound calcineurin toggles active and repressive transcriptional complexes of myocyte enhancer factor 2D. J Biol Chem 2018; 294:2543-2554. [PMID: 30523159 DOI: 10.1074/jbc.ra118.005465] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Revised: 12/04/2018] [Indexed: 12/13/2022] Open
Abstract
Myocyte enhancer factor 2 (MEF2) transcription factors are key regulators of the development and adult phenotype of diverse tissues, including skeletal and cardiac muscles. Controlled by multiple post-translational modifications, MEF2D is an effector for the Ca2+/calmodulin-dependent protein phosphatase calcineurin (CaN, PP2B, and PPP3). CaN-catalyzed dephosphorylation promotes the desumoylation and acetylation of MEF2D, increasing its transcriptional activity. Both MEF2D and CaN bind the scaffold protein muscle A-kinase-anchoring protein β (mAKAPβ), which is localized to the nuclear envelope, such that C2C12 skeletal myoblast differentiation and neonatal rat ventricular myocyte hypertrophy are inhibited by mAKAPβ signalosome targeting. Using immunoprecipitation and DNA-binding assays, we now show that the formation of mAKAPβ signalosomes is required for MEF2D dephosphorylation, desumoylation, and acetylation in C2C12 cells. Reduced MEF2D phosphorylation was coupled to a switch from type IIa histone deacetylase to p300 histone acetylase binding that correlated with increased MEF2D-dependent gene expression and ventricular myocyte hypertrophy. Together, these results highlight the importance of mAKAPβ signalosomes for regulating MEF2D activity in striated muscle, affirming mAKAPβ as a nodal regulator in the myocyte intracellular signaling network.
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Affiliation(s)
- Jinliang Li
- From the Departments of Ophthalmology and Cardiovascular Medicine, Byers Eye Institute, and Spencer Center for Vision Research, Stanford Cardiovascular Institute, Stanford University, Palo Alto, California 94304-1209 and
| | - Shania Aponte Paris
- the Calhoun Center for Cardiology, University of Connecticut Health Center, Farmington, Connecticut 06030
| | - Hrishikesh Thakur
- From the Departments of Ophthalmology and Cardiovascular Medicine, Byers Eye Institute, and Spencer Center for Vision Research, Stanford Cardiovascular Institute, Stanford University, Palo Alto, California 94304-1209 and
| | - Michael S Kapiloff
- From the Departments of Ophthalmology and Cardiovascular Medicine, Byers Eye Institute, and Spencer Center for Vision Research, Stanford Cardiovascular Institute, Stanford University, Palo Alto, California 94304-1209 and
| | - Kimberly L Dodge-Kafka
- the Calhoun Center for Cardiology, University of Connecticut Health Center, Farmington, Connecticut 06030
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13
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Zhang S, Li Z, Zhang L, Xu Z. MEF2‑activated long non‑coding RNA PCGEM1 promotes cell proliferation in hormone‑refractory prostate cancer through downregulation of miR‑148a. Mol Med Rep 2018; 18:202-208. [PMID: 29749452 PMCID: PMC6059670 DOI: 10.3892/mmr.2018.8977] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Accepted: 01/26/2017] [Indexed: 01/04/2023] Open
Abstract
Prostate cancer gene expression marker 1 (PCGEM1) is a prostate-specific gene overexpressed in prostate cancer cells that promotes cell proliferation. To study the molecular mechanism of PCGEM1 function in hormone-refractory prostate cancer, the interaction between myocyte enhancer factor 2 (MEF2) and PCGEM1 was assessed by a luciferase reporter assay and chromatin immunoprecipitation (ChIP) assay. In addition, the underlying mechanism of PCGEM1 regulating expression of microRNA (miR)-148a in PC3 prostate cancer cells was evaluated. Relative expression levels were measured by reverse transcription-quantitative polymerase chain reaction, and early apoptosis was measured by flow cytometry. PCGEM1 was demonstrated to be overexpressed in prostate cancer tissues compared with noncancerous tissues. Expression levels of PCGEM1 in PC3 cancer cells were demonstrated to be regulated by MEF2, as PCGME1 mRNA was increased by MEF2 overexpression but decreased by MEF2 silencing. MEF2 was also demonstrated to enhance the activity of PCGEM1 promoter and thus promote PCGEM1 transcription. In addition, downregulation of PCGEM1 expression in PC3 cells increased expression of miR-148a. By contrast, overexpression of PCGEM1 decreased miR-148a expression. Finally, PCGME1 silencing by small interfering RNA significantly induced early cell apoptosis but this effect was reduced by a miR-148a inhibitor. In conclusion, the present study demonstrated a positive regulatory association between MEF2 and PCGEM1, and a reciprocal negative regulatory association between PCGEM1 and miR-148a that controls cell apoptosis. The present study, therefore, provides new insights into the mechanism of PCGEM1 function in prostate cancer development.
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Affiliation(s)
- Shibao Zhang
- Department of Urology, Ji'nan Central Hospital Affiliated to Shandong University, Ji'nan, Shandong 250013, P.R. China
| | - Zongwu Li
- Department of Urology, Ji'nan Central Hospital Affiliated to Shandong University, Ji'nan, Shandong 250013, P.R. China
| | - Longyang Zhang
- Department of Urology, Ji'nan Central Hospital Affiliated to Shandong University, Ji'nan, Shandong 250013, P.R. China
| | - Zhonghua Xu
- Department of Urology, Qilu Hospital of Shandong University, Ji'nan, Shandong 250012, P.R. China
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Dodge-Kafka KL, Gildart M, Li J, Thakur H, Kapiloff MS. Bidirectional regulation of HDAC5 by mAKAPβ signalosomes in cardiac myocytes. J Mol Cell Cardiol 2018. [PMID: 29522762 DOI: 10.1016/j.yjmcc.2018.03.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Class IIa histone deacetylases (HDACs) are transcriptional repressors whose nuclear export in the cardiac myocyte is associated with the induction of pathological gene expression and cardiac remodeling. Class IIa HDACs are regulated by multiple, functionally opposing post-translational modifications, including phosphorylation by protein kinase D (PKD) that promotes nuclear export and phosphorylation by protein kinase A (PKA) that promotes nuclear import. We have previously shown that the scaffold protein muscle A-kinase anchoring protein β (mAKAPβ) orchestrates signaling in the cardiac myocyte required for pathological cardiac remodeling, including serving as a scaffold for both PKD and PKA. We now show that mAKAPβ is a scaffold for HDAC5 in cardiac myocytes, forming signalosomes containing HDAC5, PKD, and PKA. Inhibition of mAKAPβ expression attenuated the phosphorylation of HDAC5 by PKD and PKA in response to α- and β-adrenergic receptor stimulation, respectively. Importantly, disruption of mAKAPβ-HDAC5 anchoring prevented the induction of HDAC5 nuclear export by α-adrenergic receptor signaling and PKD phosphorylation. In addition, disruption of mAKAPβ-PKA anchoring prevented the inhibition by β-adrenergic receptor stimulation of α-adrenergic-induced HDAC5 nuclear export. Together, these data establish that mAKAPβ signalosomes serve to bidirectionally regulate the nuclear-cytoplasmic localization of class IIa HDACs. Thus, the mAKAPβ scaffold serves as a node in the myocyte regulatory network controlling both the repression and activation of pathological gene expression in health and disease, respectively.
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Affiliation(s)
- Kimberly L Dodge-Kafka
- Calhoun Center for Cardiology, University of Connecticut Health Center, Cardiac Signal Transduction and Cellular Biology Laboratory, Farmington, CT, USA.
| | - Moriah Gildart
- Calhoun Center for Cardiology, University of Connecticut Health Center, Cardiac Signal Transduction and Cellular Biology Laboratory, Farmington, CT, USA
| | - Jinliang Li
- Departments of Ophthalmology and Medicine, Stanford Cardiovascular Institute Stanford University, Palo Alto, CA, USA
| | - Hrishikesh Thakur
- Departments of Ophthalmology and Medicine, Stanford Cardiovascular Institute Stanford University, Palo Alto, CA, USA
| | - Michael S Kapiloff
- Departments of Ophthalmology and Medicine, Stanford Cardiovascular Institute Stanford University, Palo Alto, CA, USA.
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15
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Function of Adenylyl Cyclase in Heart: the AKAP Connection. J Cardiovasc Dev Dis 2018; 5:jcdd5010002. [PMID: 29367580 PMCID: PMC5872350 DOI: 10.3390/jcdd5010002] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Revised: 01/09/2018] [Accepted: 01/11/2018] [Indexed: 12/13/2022] Open
Abstract
Cyclic adenosine monophosphate (cAMP), synthesized by adenylyl cyclase (AC), is a universal second messenger that regulates various aspects of cardiac physiology from contraction rate to the initiation of cardioprotective stress response pathways. Local pools of cAMP are maintained by macromolecular complexes formed by A-kinase anchoring proteins (AKAPs). AKAPs facilitate control by bringing together regulators of the cAMP pathway including G-protein-coupled receptors, ACs, and downstream effectors of cAMP to finely tune signaling. This review will summarize the distinct roles of AC isoforms in cardiac function and how interactions with AKAPs facilitate AC function, highlighting newly appreciated roles for lesser abundant AC isoforms.
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16
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Liu X, Wang Y, Hou L, Xiong Y, Zhao S. Fibroblast Growth Factor 21 (FGF21) Promotes Formation of Aerobic Myofibers via the FGF21-SIRT1-AMPK-PGC1α Pathway. J Cell Physiol 2017; 232:1893-1906. [DOI: 10.1002/jcp.25735] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Accepted: 12/13/2016] [Indexed: 12/13/2022]
Affiliation(s)
- Xinyi Liu
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of the Ministry of Education and Key Laboratory of Swine Genetics and Breeding of the Ministry of Agriculture; Huazhong Agricultural University; Wuhan Hubei P. R. China
| | - Yongliang Wang
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of the Ministry of Education and Key Laboratory of Swine Genetics and Breeding of the Ministry of Agriculture; Huazhong Agricultural University; Wuhan Hubei P. R. China
| | - Liming Hou
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of the Ministry of Education and Key Laboratory of Swine Genetics and Breeding of the Ministry of Agriculture; Huazhong Agricultural University; Wuhan Hubei P. R. China
| | - Yuanzhu Xiong
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of the Ministry of Education and Key Laboratory of Swine Genetics and Breeding of the Ministry of Agriculture; Huazhong Agricultural University; Wuhan Hubei P. R. China
| | - Shuhong Zhao
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of the Ministry of Education and Key Laboratory of Swine Genetics and Breeding of the Ministry of Agriculture; Huazhong Agricultural University; Wuhan Hubei P. R. China
- The Cooperative Innovation Center for Sustainable Pig Production; Wuhan Hubei P. R. China
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Abstract
Cardiac remodeling is regulated by an extensive intracellular signal transduction network. Each of the many signaling pathways in this network contributes uniquely to the control of cellular adaptation. In the last few years, it has become apparent that multimolecular signaling complexes or "signalosomes" are important for fidelity in intracellular signaling and for mediating crosstalk between the different signaling pathways. These complexes integrate upstream signals and control downstream effectors. In the cardiac myocyte, the protein mAKAPβ serves as a scaffold for a large signalosome that is responsive to cAMP, calcium, hypoxia, and mitogen-activated protein kinase signaling. The main function of mAKAPβ signalosomes is to modulate stress-related gene expression regulated by the transcription factors NFATc, MEF2, and HIF-1α and type II histone deacetylases that control pathological cardiac hypertrophy.
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18
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Lee SW, Won JY, Yang J, Lee J, Kim SY, Lee EJ, Kim HS. AKAP6 inhibition impairs myoblast differentiation and muscle regeneration: Positive loop between AKAP6 and myogenin. Sci Rep 2015; 5:16523. [PMID: 26563778 PMCID: PMC4643297 DOI: 10.1038/srep16523] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2015] [Accepted: 10/13/2015] [Indexed: 01/27/2023] Open
Abstract
Skeletal muscle regeneration occurs continuously to repair muscle damage incurred during normal activity and in chronic disease or injury. Herein, we report that A-kinase anchoring protein 6 (AKAP6) is important for skeletal myoblast differentiation and muscle regeneration. Compared with unstimulated skeletal myoblasts that underwent proliferation, differentiated cells show significant stimulation of AKAP6 expression. AKAP6 knockdown with siRNA effectively halts the formation of myotubes and decreases the expression of the differentiation markers myogenin and myosin heavy chain. When shAKAP6-lentivirus is delivered to mice with cardiotoxin (CTX)-induced muscle injury, muscle regeneration is impaired compared with that of mice injected with control shMock-lentivirus. The motor functions of mice infected with shAKAP6-lentivirus (CTX+shAK6) are significantly worse than those of mice infected with shMock-lentivirus (CTX+shMock). Mechanistic analysis showed that AKAP6 promotes myogenin expression through myocyte enhancer factor 2A (MEF2A). Notably, myogenin increases AKAP6 expression as well. The results of chromatin immunoprecipitation and luciferase assays showed that myogenin binds to an E-box site on the AKAP6 promoter. Taken together, our findings demonstrate a novel interplay between AKAP6 and myogenin, and we suggest that AKAP6 is an important regulator of myoblast differentiation, myotube formation, and muscle regeneration.
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Affiliation(s)
- Sae-Won Lee
- Biomedical Research Institute and IRICT, Seoul National University Hospital, 101 DaeHak-ro, JongRo-gu Seoul, 110-744, Republic of Korea
| | - Joo-Yun Won
- Biomedical Research Institute and IRICT, Seoul National University Hospital, 101 DaeHak-ro, JongRo-gu Seoul, 110-744, Republic of Korea
| | - Jimin Yang
- Biomedical Research Institute and IRICT, Seoul National University Hospital, 101 DaeHak-ro, JongRo-gu Seoul, 110-744, Republic of Korea
| | - Jaewon Lee
- Biomedical Research Institute and IRICT, Seoul National University Hospital, 101 DaeHak-ro, JongRo-gu Seoul, 110-744, Republic of Korea
| | - Su-Yeon Kim
- Biomedical Research Institute and IRICT, Seoul National University Hospital, 101 DaeHak-ro, JongRo-gu Seoul, 110-744, Republic of Korea
| | - Eun Ju Lee
- Biomedical Research Institute and IRICT, Seoul National University Hospital, 101 DaeHak-ro, JongRo-gu Seoul, 110-744, Republic of Korea
| | - Hyo-Soo Kim
- Department of Internal Medicine and IRICT, Seoul National University Hospital, 101 DaeHak-ro, JongRo-gu Seoul, 110-744, Republic of Korea.,Department of Molecular Medicine and Biopharmaceutical Sciences, Graduate School of Convergence Science and Technology, Seoul National University, Korea
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19
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Martinez EC, Passariello CL, Li J, Matheson CJ, Dodge-Kafka K, Reigan P, Kapiloff MS. RSK3: A regulator of pathological cardiac remodeling. IUBMB Life 2015; 67:331-7. [PMID: 25988524 PMCID: PMC4449288 DOI: 10.1002/iub.1383] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Accepted: 04/08/2015] [Indexed: 12/18/2022]
Abstract
The family of p90 ribosomal S6 kinases (RSKs) are pleiotropic effectors for extracellular signal-regulated kinase signaling pathways. Recently, RSK3 was shown to be important for pathological remodeling of the heart. Although cardiac myocyte hypertrophy can be compensatory for increased wall stress, in chronic heart diseases, this nonmitotic cell growth is usually associated with interstitial fibrosis, increased cell death, and decreased cardiac function. Although RSK3 is less abundant in the cardiac myocyte than other RSK family members, RSK3 appears to serve a unique role in cardiac myocyte stress responses. A potential mechanism conferring the unique function of RSK3 in the heart is anchoring by the scaffold protein muscle A-kinase anchoring protein β (mAKAPβ). Recent findings suggest that RSK3 should be considered as a therapeutic target for the prevention of heart failure, a clinical syndrome of major public health significance.
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Affiliation(s)
- Eliana C. Martinez
- Department of Pediatrics, Division of Cardiology, Cardiac Signal Transduction and Cellular Biology Laboratory, Interdisciplinary Stem Cell Institute, Miller School of Medicine, University of Miami, Miami, FL, USA
| | - Catherine L. Passariello
- Department of Pediatrics, Division of Cardiology, Cardiac Signal Transduction and Cellular Biology Laboratory, Interdisciplinary Stem Cell Institute, Miller School of Medicine, University of Miami, Miami, FL, USA
| | - Jinliang Li
- Department of Pediatrics, Division of Cardiology, Cardiac Signal Transduction and Cellular Biology Laboratory, Interdisciplinary Stem Cell Institute, Miller School of Medicine, University of Miami, Miami, FL, USA
| | - Christopher J. Matheson
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado, Aurora, CO, USA
| | - Kimberly Dodge-Kafka
- Calhoun Center for Cardiology, University of Connecticut Health Center, Farmington, CT, USA
| | - Philip Reigan
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado, Aurora, CO, USA
| | - Michael S. Kapiloff
- Department of Pediatrics, Division of Cardiology, Cardiac Signal Transduction and Cellular Biology Laboratory, Interdisciplinary Stem Cell Institute, Miller School of Medicine, University of Miami, Miami, FL, USA
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20
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Kritzer MD, Li J, Passariello CL, Gayanilo M, Thakur H, Dayan J, Dodge-Kafka K, Kapiloff MS. The scaffold protein muscle A-kinase anchoring protein β orchestrates cardiac myocyte hypertrophic signaling required for the development of heart failure. Circ Heart Fail 2014; 7:663-72. [PMID: 24812305 DOI: 10.1161/circheartfailure.114.001266] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
BACKGROUND Cardiac myocyte hypertrophy is regulated by an extensive intracellular signal transduction network. In vitro evidence suggests that the scaffold protein muscle A-kinase anchoring protein β (mAKAPβ) serves as a nodal organizer of hypertrophic signaling. However, the relevance of mAKAPβ signalosomes to pathological remodeling and heart failure in vivo remains unknown. METHODS AND RESULTS Using conditional, cardiac myocyte-specific gene deletion, we now demonstrate that mAKAPβ expression in mice is important for the cardiac hypertrophy induced by pressure overload and catecholamine toxicity. mAKAPβ targeting prevented the development of heart failure associated with long-term transverse aortic constriction, conferring a survival benefit. In contrast to 29% of control mice (n=24), only 6% of mAKAPβ knockout mice (n=31) died in the 16 weeks of pressure overload (P=0.02). Accordingly, mAKAPβ knockout inhibited myocardial apoptosis and the development of interstitial fibrosis, left atrial hypertrophy, and pulmonary edema. This improvement in cardiac status correlated with the attenuated activation of signaling pathways coordinated by the mAKAPβ scaffold, including the decreased phosphorylation of protein kinase D1 and histone deacetylase 4 that we reveal to participate in a new mAKAP signaling module. Furthermore, mAKAPβ knockout inhibited pathological gene expression directed by myocyte-enhancer factor-2 and nuclear factor of activated T-cell transcription factors that associate with the scaffold. CONCLUSIONS mAKAPβ orchestrates signaling that regulates pathological cardiac remodeling in mice. Targeting of the underlying physical architecture of signaling networks, including mAKAPβ signalosome formation, may constitute an effective therapeutic strategy for the prevention and treatment of pathological remodeling and heart failure.
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Affiliation(s)
- Michael D Kritzer
- From the Cardiac Signal Transduction and Cellular Biology Laboratory, Interdisciplinary Stem Cell Institute, Departments of Pediatrics and Medicine, Leonard M. Miller School of Medicine, University of Miami, FL (M.D.K., J.L., C.L.P., M.G., H.T., J.D., M.S.K.); and Calhoun Center for Cardiology, University of Connecticut Health Center, Farmington (K.D.-K.).
| | - Jinliang Li
- From the Cardiac Signal Transduction and Cellular Biology Laboratory, Interdisciplinary Stem Cell Institute, Departments of Pediatrics and Medicine, Leonard M. Miller School of Medicine, University of Miami, FL (M.D.K., J.L., C.L.P., M.G., H.T., J.D., M.S.K.); and Calhoun Center for Cardiology, University of Connecticut Health Center, Farmington (K.D.-K.)
| | - Catherine L Passariello
- From the Cardiac Signal Transduction and Cellular Biology Laboratory, Interdisciplinary Stem Cell Institute, Departments of Pediatrics and Medicine, Leonard M. Miller School of Medicine, University of Miami, FL (M.D.K., J.L., C.L.P., M.G., H.T., J.D., M.S.K.); and Calhoun Center for Cardiology, University of Connecticut Health Center, Farmington (K.D.-K.)
| | - Marjorie Gayanilo
- From the Cardiac Signal Transduction and Cellular Biology Laboratory, Interdisciplinary Stem Cell Institute, Departments of Pediatrics and Medicine, Leonard M. Miller School of Medicine, University of Miami, FL (M.D.K., J.L., C.L.P., M.G., H.T., J.D., M.S.K.); and Calhoun Center for Cardiology, University of Connecticut Health Center, Farmington (K.D.-K.)
| | - Hrishikesh Thakur
- From the Cardiac Signal Transduction and Cellular Biology Laboratory, Interdisciplinary Stem Cell Institute, Departments of Pediatrics and Medicine, Leonard M. Miller School of Medicine, University of Miami, FL (M.D.K., J.L., C.L.P., M.G., H.T., J.D., M.S.K.); and Calhoun Center for Cardiology, University of Connecticut Health Center, Farmington (K.D.-K.)
| | - Joseph Dayan
- From the Cardiac Signal Transduction and Cellular Biology Laboratory, Interdisciplinary Stem Cell Institute, Departments of Pediatrics and Medicine, Leonard M. Miller School of Medicine, University of Miami, FL (M.D.K., J.L., C.L.P., M.G., H.T., J.D., M.S.K.); and Calhoun Center for Cardiology, University of Connecticut Health Center, Farmington (K.D.-K.)
| | - Kimberly Dodge-Kafka
- From the Cardiac Signal Transduction and Cellular Biology Laboratory, Interdisciplinary Stem Cell Institute, Departments of Pediatrics and Medicine, Leonard M. Miller School of Medicine, University of Miami, FL (M.D.K., J.L., C.L.P., M.G., H.T., J.D., M.S.K.); and Calhoun Center for Cardiology, University of Connecticut Health Center, Farmington (K.D.-K.)
| | - Michael S Kapiloff
- From the Cardiac Signal Transduction and Cellular Biology Laboratory, Interdisciplinary Stem Cell Institute, Departments of Pediatrics and Medicine, Leonard M. Miller School of Medicine, University of Miami, FL (M.D.K., J.L., C.L.P., M.G., H.T., J.D., M.S.K.); and Calhoun Center for Cardiology, University of Connecticut Health Center, Farmington (K.D.-K.)
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21
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Li J, Vargas MAX, Kapiloff MS, Dodge-Kafka KL. Regulation of MEF2 transcriptional activity by calcineurin/mAKAP complexes. Exp Cell Res 2012; 319:447-54. [PMID: 23261540 DOI: 10.1016/j.yexcr.2012.12.016] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2012] [Revised: 11/28/2012] [Accepted: 12/13/2012] [Indexed: 10/27/2022]
Abstract
The calcium/calmodulin-dependent protein phosphatase calcineurin is required for the induction of transcriptional events that initiate and promote myogenic differentiation. An important effector for calcineurin in striated muscle is the transcription factor myocyte enhancer factor 2 (MEF2). The targeting of the enzyme and substrate to specific intracellular compartments by scaffold proteins often confers specificity in phosphatase activity. We now show that the scaffolding protein mAKAP organizes a calcineurin/MEF2 signaling complex in myocytes, regulating gene transcription. A calcineurin/mAKAP/MEF2 complex can be isolated from C2C12 cells and cardiac myocytes, and the calcineurin/MEF2 association is dependent on mAKAP expression. We have identified a peptide comprising the calcineurin binding domain in mAKAP that can disrupt the binding of the phosphatase to the scaffold in vivo. Dominant interference of calcineurin/mAKAP binding blunts the increase in MEF2 transcriptional activity seen during myoblast differentiation, as well as the expression of endogenous MEF2-target genes. Furthermore, disruption of calcineurin binding to mAKAP in cardiac myocytes inhibits adrenergic-induced cellular hypertrophy. Together these data illustrate the importance of calcineurin anchoring by the mAKAP scaffold for MEF2 regulation.
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Affiliation(s)
- Jinliang Li
- Cardiac Signal Transduction and Cellular Biology Laboratory, Interdisciplinary Stem Cell Institute, Department of Pediatrics, University of Miami Miller School of Medicine, Miami, FL 33101, United States
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