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Menges L, Giesen J, Yilmaz K, Mergia E, Füchtbauer A, Füchtbauer EM, Koesling D, Russwurm M. It takes two to tango: cardiac fibroblast-derived NO-induced cGMP enters cardiac myocytes and increases cAMP by inhibiting PDE3. Commun Biol 2023; 6:504. [PMID: 37165086 PMCID: PMC10172304 DOI: 10.1038/s42003-023-04880-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Accepted: 04/27/2023] [Indexed: 05/12/2023] Open
Abstract
The occurrence of NO/cGMP signalling in cardiac cells is a matter of debate. Recent measurements with a FRET-based cGMP indicator in isolated cardiac cells revealed NO-induced cGMP signals in cardiac fibroblasts while cardiomyocytes were devoid of these signals. In a fibroblast/myocyte co-culture model though, cGMP formed in fibroblasts in response to NO entered cardiomyocytes via gap junctions. Here, we demonstrate gap junction-mediated cGMP transfer from cardiac fibroblasts to myocytes in intact tissue. In living cardiac slices of mice with cardiomyocyte-specific expression of a FRET-based cGMP indicator (αMHC/cGi-500), NO-dependent cGMP signals were shown to occur in myocytes, to depend on gap junctions and to be degraded mainly by PDE3. Stimulation of NO-sensitive guanylyl cyclase enhanced Forskolin- and Isoproterenol-induced cAMP and phospholamban phosphorylation. Genetic inactivation of NO-GC in Tcf21-expressing cardiac fibroblasts abrogated the synergistic action of NO-GC stimulation on Iso-induced phospholamban phosphorylation, identifying fibroblasts as cGMP source and substantiating the necessity of cGMP-transfer to myocytes. In sum, NO-stimulated cGMP formed in cardiac fibroblasts enters cardiomyocytes in native tissue where it exerts an inhibitory effect on cAMP degradation by PDE3, thereby increasing cAMP and downstream effects in cardiomyocytes. Hence, enhancing β-receptor-induced contractile responses appears as one of NO/cGMP's functions in the non-failing heart.
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Affiliation(s)
- Lukas Menges
- Institute of Pharmacology and Toxicology, Ruhr-University Bochum, 44780, Bochum, Germany
| | - Jan Giesen
- Institute of Pharmacology and Toxicology, Ruhr-University Bochum, 44780, Bochum, Germany
| | - Kerem Yilmaz
- Institute of Pharmacology and Toxicology, Ruhr-University Bochum, 44780, Bochum, Germany
| | - Evanthia Mergia
- Institute of Pharmacology and Toxicology, Ruhr-University Bochum, 44780, Bochum, Germany
| | - Annette Füchtbauer
- Department of Molecular Biology and Genetics, Aarhus University, 8000, Aarhus C, Denmark
| | | | - Doris Koesling
- Institute of Pharmacology and Toxicology, Ruhr-University Bochum, 44780, Bochum, Germany
| | - Michael Russwurm
- Institute of Pharmacology and Toxicology, Ruhr-University Bochum, 44780, Bochum, Germany.
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Gray SR, Ye L, Ye JY, Paukert M. Noradrenergic terminal short-term potentiation enables modality-selective integration of sensory input and vigilance state. SCIENCE ADVANCES 2021; 7:eabk1378. [PMID: 34919424 PMCID: PMC8682997 DOI: 10.1126/sciadv.abk1378] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Accepted: 10/28/2021] [Indexed: 06/14/2023]
Abstract
Recent years have seen compelling demonstrations of the importance of behavioral state on sensory processing and attention. Arousal plays a dominant role in controlling brain-wide neural activity patterns, particularly through modulation by norepinephrine. Noradrenergic brainstem nuclei, including locus coeruleus, can be activated by stimuli of multiple sensory modalities and broadcast modulatory signals via axonal projections throughout the brain. This organization might suggest proportional brain-wide norepinephrine release during states of heightened vigilance. Here, however, we have found that low-intensity, nonarousing visual stimuli enhanced vigilance-dependent noradrenergic signaling locally in visual cortex, revealed using dual-site fiber photometry to monitor noradrenergic Ca2+ responses of astroglia simultaneously in cerebellum and visual cortex and two-photon microscopy to monitor noradrenergic axonal terminal Ca2+ dynamics. Nitric oxide, following N-methyl-d-aspartate receptor activation in neuronal nitric oxide synthase-positive interneurons, mediated transient acceleration of norepinephrine-dependent astroglia Ca2+ activation. These findings reveal a candidate cortical microcircuit for sensory modality-selective modulation of attention.
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Affiliation(s)
- Shawn R. Gray
- Department of Cellular and Integrative Physiology, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
- Joint UTSA/UTHSCSA Graduate Program in Biomedical Engineering, San Antonio, TX, USA
| | - Liang Ye
- Department of Cellular and Integrative Physiology, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Jing Yong Ye
- Joint UTSA/UTHSCSA Graduate Program in Biomedical Engineering, San Antonio, TX, USA
- Department of Biomedical Engineering, University of Texas at San Antonio, San Antonio, TX, USA
| | - Martin Paukert
- Department of Cellular and Integrative Physiology, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
- Joint UTSA/UTHSCSA Graduate Program in Biomedical Engineering, San Antonio, TX, USA
- Center for Biomedical Neuroscience, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
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3
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Friebe A, Sandner P, Schmidtko A. cGMP: a unique 2nd messenger molecule - recent developments in cGMP research and development. NAUNYN-SCHMIEDEBERG'S ARCHIVES OF PHARMACOLOGY 2020; 393:287-302. [PMID: 31853617 PMCID: PMC7260148 DOI: 10.1007/s00210-019-01779-z] [Citation(s) in RCA: 80] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Accepted: 11/22/2019] [Indexed: 12/11/2022]
Abstract
Cyclic guanosine monophosphate (cGMP) is a unique second messenger molecule formed in different cell types and tissues. cGMP targets a variety of downstream effector molecules and, thus, elicits a very broad variety of cellular effects. Its production is triggered by stimulation of either soluble guanylyl cyclase (sGC) or particulate guanylyl cyclase (pGC); both enzymes exist in different isoforms. cGMP-induced effects are regulated by endogenous receptor ligands such as nitric oxide (NO) and natriuretic peptides (NPs). Depending on the distribution of sGC and pGC and the formation of ligands, this pathway regulates not only the cardiovascular system but also the kidney, lung, liver, and brain function; in addition, the cGMP pathway is involved in the pathogenesis of fibrosis, inflammation, or neurodegeneration and may also play a role in infectious diseases such as malaria. Moreover, new pharmacological approaches are being developed which target sGC- and pGC-dependent pathways for the treatment of various diseases. Therefore, it is of key interest to understand this pathway from scratch, beginning with the molecular basis of cGMP generation, the structure and function of both guanylyl cyclases and cGMP downstream targets; research efforts also focus on the subsequent signaling cascades, their potential crosstalk, and also the translational and, ultimately, the clinical implications of cGMP modulation. This review tries to summarize the contributions to the "9th International cGMP Conference on cGMP Generators, Effectors and Therapeutic Implications" held in Mainz in 2019. Presented data will be discussed and extended also in light of recent landmark findings and ongoing activities in the field of preclinical and clinical cGMP research.
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Affiliation(s)
- Andreas Friebe
- Institute of Physiology, University of Würzburg, Röntgenring 9, D-97070 Würzburg, Germany
| | - Peter Sandner
- Drug Discovery, Bayer AG, Aprather Weg 18a, D-42096 Wuppertal, Germany and Institute of Pharmacology, Hannover Medical School, Carl-Neuberg-Str. 1, D-30625 Hannover, Germany
| | - Achim Schmidtko
- Institute of Pharmacology and Clinical Pharmacy, Goethe University, Max-von-Laue-Str. 9, D-60438 Frankfurt am Main, Germany
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Menges L, Krawutschke C, Füchtbauer EM, Füchtbauer A, Sandner P, Koesling D, Russwurm M. Mind the gap (junction): cGMP induced by nitric oxide in cardiac myocytes originates from cardiac fibroblasts. Br J Pharmacol 2019; 176:4696-4707. [PMID: 31423565 PMCID: PMC6965686 DOI: 10.1111/bph.14835] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Revised: 07/23/2019] [Accepted: 08/05/2019] [Indexed: 01/02/2023] Open
Abstract
Background and Purpose The intracellular signalling molecule cGMP, formed by NO‐sensitive GC (NO–GC), has an established function in the vascular system. Despite numerous reports about NO‐induced cGMP effects in the heart, the underlying cGMP signals are poorly characterized. Experimental Approach Therefore, we analysed cGMP signals in cardiac myocytes and fibroblasts isolated from knock‐in mice expressing a FRET‐based cGMP indicator. Key Results Whereas in cardiac myocytes, none of the known NO–GC‐activating substances (NO, GC activators, and GC stimulators) increased cGMP even in the presence of PDE inhibitors, they induced substantial cGMP increases in cardiac fibroblasts. As cardiac myocytes and fibroblasts are electrically connected via gap junctions, we asked whether cGMP can take the same route. Indeed, in cardiomyocytes co‐cultured on cardiac fibroblasts, NO‐induced cGMP signals were detectable, and two groups of unrelated gap junction inhibitors abolished these signals. Conclusion and Implication We conclude that NO‐induced cGMP formed in cardiac fibroblasts enters cardiac myocytes via gap junctions thereby turning cGMP into an intercellular signalling molecule. The findings shed new light on NO/cGMP signalling in the heart and will potentially broaden therapeutic opportunities for cardiac disease.
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Affiliation(s)
- Lukas Menges
- Institute of Pharmacology and Toxicology, Ruhr-University Bochum, Bochum, Germany
| | | | - Ernst-Martin Füchtbauer
- Department of Molecular Biology and Genetics, Molecular Cell and Developmental Biology Aarhus University, Aarhus C, Denmark
| | - Annette Füchtbauer
- Department of Molecular Biology and Genetics, Molecular Cell and Developmental Biology Aarhus University, Aarhus C, Denmark
| | - Peter Sandner
- Drug Discovery, Cardiovascular Research, Bayer AG, Pharmaceuticals, Wuppertal, Germany
| | - Doris Koesling
- Institute of Pharmacology and Toxicology, Ruhr-University Bochum, Bochum, Germany
| | - Michael Russwurm
- Institute of Pharmacology and Toxicology, Ruhr-University Bochum, Bochum, Germany
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Rogers NM, Seeger F, Garcin ED, Roberts DD, Isenberg JS. Regulation of soluble guanylate cyclase by matricellular thrombospondins: implications for blood flow. Front Physiol 2014; 5:134. [PMID: 24772092 PMCID: PMC3983488 DOI: 10.3389/fphys.2014.00134] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2014] [Accepted: 03/18/2014] [Indexed: 01/16/2023] Open
Abstract
Nitric oxide (NO) maintains cardiovascular health by activating soluble guanylate cyclase (sGC) to increase cellular cGMP levels. Cardiovascular disease is characterized by decreased NO-sGC-cGMP signaling. Pharmacological activators and stimulators of sGC are being actively pursued as therapies for acute heart failure and pulmonary hypertension. Here we review molecular mechanisms that modulate sGC activity while emphasizing a novel biochemical pathway in which binding of the matricellular protein thrombospondin-1 (TSP1) to the cell surface receptor CD47 causes inhibition of sGC. We discuss the therapeutic implications of this pathway for blood flow, tissue perfusion, and cell survival under physiologic and disease conditions.
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Affiliation(s)
- Natasha M Rogers
- Department of Medicine, Vascular Medicine Institute, University of Pittsburgh School of Medicine Pittsburgh, PA, USA
| | - Franziska Seeger
- Department of Chemistry and Biochemistry, University of Maryland Baltimore County Baltimore, MD, USA
| | - Elsa D Garcin
- Department of Chemistry and Biochemistry, University of Maryland Baltimore County Baltimore, MD, USA
| | - David D Roberts
- Laboratory of Pathology, Center for Cancer Research, National Cancer Institute, NIH Bethesda, MD, USA
| | - Jeffrey S Isenberg
- Department of Medicine, Vascular Medicine Institute, University of Pittsburgh School of Medicine Pittsburgh, PA, USA ; Department of Medicine, Division of Pulmonary, Allergy and Critical Care Medicine, University of Pittsburgh School of Medicine Pittsburgh, PA, USA
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Contestabile A. Role of nitric oxide in cerebellar development and function: focus on granule neurons. THE CEREBELLUM 2012; 11:50-61. [PMID: 21104176 DOI: 10.1007/s12311-010-0234-1] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
More than 20 years of research have firmly established important roles of the diffusible messenger molecule, nitric oxide (NO), in cerebellar development and function. Granule neurons are main players in every NO-related mechanism involving cerebellar function and dysfunction. Granule neurons are endowed with remarkable amounts of the Ca(2+)-dependent neuronal isoform of nitric oxide synthase and can directly respond to endogenously produced NO or induce responses in neighboring cells taking advantage of the high diffusibility of the molecule. Nitric oxide acts as a negative regulator of granule cell precursor proliferation and promotes survival and differentiation of these neurons. Nitric oxide is neuroprotective towards granule neurons challenged with toxic insults. Nitric oxide is a main regulator of bidirectional plasticity at parallel fiber-Purkinje neuron synapses, inducing long-term depression (LTD) or long-term potentiation (LTP) depending on postsynaptic Ca(2+) levels, thus playing a central role in cerebellar learning related to motor control. Granule neurons cooperate with glial cells, in particular with microglia, in the regulation of NO production through the respective forms of NOS present in the two cellular types. Aim of the present paper is to review the state of the art and the improvement of our understanding of NO functions in cerebellar granule neurons obtained during the last two decades and to outline possible future development of the research.
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Affiliation(s)
- Antonio Contestabile
- Department of Biology, University of Bologna, Via Selmi 3, 40126 Bologna, Italy.
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7
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Held KF, Dostmann WR. Sub-Nanomolar Sensitivity of Nitric Oxide Mediated Regulation of cGMP and Vasomotor Reactivity in Vascular Smooth Muscle. Front Pharmacol 2012; 3:130. [PMID: 22807915 PMCID: PMC3395022 DOI: 10.3389/fphar.2012.00130] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2012] [Accepted: 06/20/2012] [Indexed: 11/20/2022] Open
Abstract
Nitric oxide (NO) is a potent dilator of vascular smooth muscle (VSM) by modulating intracellular cGMP ([cGMP]i) through the binding and activation of receptor guanylyl cylases (sGC). The kinetic relationship of NO and sGC, as well as the subsequent regulation of [cGMP]i and its effects on blood vessel vasodilation, is largely unknown. In isolated VSM cells exposed to both pulsed and clamped NO we observed transient and sustained increases in [cGMP]i, with sub-nanomolar sensitivity to NO (EC50 = 0.28 nM). Through the use of pharmacological inhibitors of sGC, PDE5, and PKG, a comprehensive VSM-specific modeling algorithm was constructed to elucidate the concerted activity profiles of sGC, PDE5, phosphorylated PDE5, and PDE1 in the maintenance of [cGMP]i. In small pressure-constricted arteries of the resistance vasculature we again observed both transient and sustained relaxations upon delivery of pulsed and clamped NO, while maintaining a similarly high sensitivity to NO (EC50 = 0.42 nM). Our results propose an intricate dependency of the messengers and enzymes involved in cGMP homeostasis, and vasodilation in VSM. Particularly, the high sensitivity of sGC to NO in primary tissue indicates how small changes in the concentrations of NO, irrespective of the form of NO delivery, can have significant effects on the dynamic regulation of vascular tone.
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Affiliation(s)
- Kara F Held
- Department of Pharmacology, College of Medicine, University of Vermont Burlington, VT, USA
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8
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Ramanathan S, Mazzalupo S, Boitano S, Montfort WR. Thrombospondin-1 and angiotensin II inhibit soluble guanylyl cyclase through an increase in intracellular calcium concentration. Biochemistry 2011; 50:7787-99. [PMID: 21823650 DOI: 10.1021/bi201060c] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Nitric oxide (NO) regulates cardiovascular hemostasis by binding to soluble guanylyl cyclase (sGC), leading to cGMP production, reduced cytosolic calcium concentration ([Ca(2+)](i)), and vasorelaxation. Thrombospondin-1 (TSP-1), a secreted matricellular protein, was recently discovered to inhibit NO signaling and sGC activity. Inhibition of sGC requires binding to cell-surface receptor CD47. Here, we show that a TSP-1 C-terminal fragment (E3CaG1) readily inhibits sGC in Jurkat T cells and that inhibition requires an increase in [Ca(2+)](i). Using flow cytometry, we show that E3CaG1 binds directly to CD47 on the surface of Jurkat T cells. Using digital imaging microscopy on live cells, we further show that E3CaG1 binding results in a substantial increase in [Ca(2+)](i), up to 300 nM. Addition of angiotensin II, a potent vasoconstrictor known to increase [Ca(2+)](i), also strongly inhibits sGC activity. sGC isolated from calcium-treated cells or from cell-free lysates supplemented with Ca(2+) remains inhibited, while addition of kinase inhibitor staurosporine prevents inhibition, indicating inhibition is likely due to phosphorylation. Inhibition is through an increase in K(m) for GTP, which rises to 834 μM for the NO-stimulated protein, a 13-fold increase over the uninhibited protein. Compounds YC-1 and BAY 41-2272, allosteric stimulators of sGC that are of interest for treating hypertension, overcome E3CaG1-mediated inhibition of NO-ligated sGC. Taken together, these data suggest that sGC not only lowers [Ca(2+)](i) in response to NO, inducing vasodilation, but also is inhibited by high [Ca(2+)](i), providing a fine balance between signals for vasodilation and vasoconstriction.
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Affiliation(s)
- Saumya Ramanathan
- Department of Molecular and Cellular Biology, University of Arizona, Tucson, Arizona 85721, United States
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Park SS, Hong M, Song CK, Jhon GJ, Lee Y, Suh M. Real-time in vivo simultaneous measurements of nitric oxide and oxygen using an amperometric dual microsensor. Anal Chem 2011; 82:7618-24. [PMID: 20715758 DOI: 10.1021/ac1013496] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
This paper reports a real-time study of the codynamical changes in the release of endogenous nitric oxide (NO) and oxygen (O(2)) consumption in a rat neocortex in vivo upon electrical stimulation using an amperometric NO/O(2) dual microsensor. Electrical stimulation induced transient cerebral hypoxia due to the increased metabolic demands that were not met by the blood volume inside the stimulated cortical region. A NO/O(2) dual microsensor was successfully used to monitor the pair of real-time dynamic changes in the tissue NO and O(2) contents. At the onset of electrical stimulation, there was an immediate decrease in the cortical tissue O(2) followed by a subsequent increase in the cortical tissue NO content. The averages of the maximum normalized concentration changes induced by the stimulation were a 0.41 (±0.04)-fold decrease in the O(2) and a 3.6 (±0.9)-fold increase in the NO concentrations when compared with the corresponding normalized basal levels. The peak increase in NO was always preceded by the peak decrease in O(2) in all animals (n = 11). The delay between the maximum decrease in O(2) and the maximum increase in NO varied from 3.1 to 54.8 s. This rather wide variation in the temporal associations was presumably attributed to the sparse distribution of NOS-containing neurons and the individual animal's differences in brain vasculatures, which suggests that a sensor with fine spatial resolution is needed to measure the location-specific real-time NO and O(2) contents. In summary, the developed NO/O(2) dual microsensor is effective for measuring the NO and O(2) contents in vivo. This study provides direct support for the dynamic role of NO in regulating the cerebral hemodynamics, particularly related to the tissue oxygenation.
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Affiliation(s)
- Sarah S Park
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul, 120-750, Korea
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10
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New insight into the functioning of nitric oxide-receptive guanylyl cyclase: physiological and pharmacological implications. Mol Cell Biochem 2009; 334:221-32. [PMID: 20012469 DOI: 10.1007/s11010-009-0318-8] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2009] [Accepted: 11/04/2009] [Indexed: 10/20/2022]
Abstract
The cellular counterpart of the "soluble" guanylyl cyclase found in tissue homogenates over 30 years ago is now recognized as the physiological receptor for nitric oxide (NO). The ligand-binding site is a prosthetic haem group that, when occupied by NO, induces a conformational change in the protein that propagates to the catalytic site, triggering conversion of GTP into cGMP. This review focuses on recent research that takes this basic information forward to the beginnings of a quantitative depiction of NO signal transduction, analogous to that achieved for other major transmitters. At its foundation is an explicit enzyme-linked receptor mechanism for NO-activated guanylyl cyclase that replicates all its main properties. In cells, NO signal transduction is subject to additional, activity-dependent modifications, notably through receptor desensitization and changes in the activity of cGMP-hydrolyzing phosphodiesterases. The measurement of these parameters under varying conditions in rat platelets has made it possible to formulate a cellular model of NO-cGMP signaling. The model helps explain cellular responses to NO and their modification by therapeutic agents acting on the guanylyl cyclase or phosphodiesterase limbs of the pathway.
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11
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Jung C, Gonon AT, Sjoquist PO, Lundberg JO, Pernow J. Arginase inhibition mediates cardioprotection during ischaemia-reperfusion. Cardiovasc Res 2009; 85:147-54. [DOI: 10.1093/cvr/cvp303] [Citation(s) in RCA: 101] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Suppression of guanylyl cyclase (beta1 subunit) expression impairs neurite outgrowth and synapse maturation in cultured cerebellar granule cells. Cell Death Differ 2009; 16:1266-78. [PMID: 19461654 DOI: 10.1038/cdd.2009.57] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
The increased expression of different soluble guanylyl cyclase (sGC) subunits during development is consistent with these proteins participating in the formation and establishment of interneuronal contacts. Functional sGC is generated by the dimerization of an alpha-subunit (sGCalpha1/2) with the beta1-subunit (sGCbeta1), and both depletion of the sGCbeta1 subunit and inhibiting sGC activity impair neurite outgrowth. Similarly, impairing sGC activity diminishes the amount of growth-associated protein (GAP-43) and synapsin I, two proteins that participate in axon elongation and synaptogenesis, suggesting a role for sGC in these processes. Indeed, fewer synapses form when sGC is inhibited, as witnessed by FM1-43 imaging and synapsin I immunostaining, and the majority of synapses that do form remain functionally immature. These findings highlight the importance of sGC in the regulation of neurite outgrowth and synapse formation, and in the functional maturation of cerebellar granule cells in vitro.
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Abstract
As a chemical transmitter in the mammalian central nervous system, nitric oxide (NO) is still thought a bit of an oddity, yet this role extends back to the beginnings of the evolution of the nervous system, predating many of the more familiar neurotransmitters. During the 20 years since it became known, evidence has accumulated for NO subserving an increasing number of functions in the mammalian central nervous system, as anticipated from the wide distribution of its synthetic and signal transduction machinery within it. This review attempts to probe beneath those functions and consider the cellular and molecular mechanisms through which NO evokes short- and long-term modifications in neural performance. With any transmitter, understanding its receptors is vital for decoding the language of communication. The receptor proteins specialised to detect NO are coupled to cGMP formation and provide an astonishing degree of amplification of even brief, low amplitude NO signals. Emphasis is given to the diverse ways in which NO receptor activation initiates changes in neuronal excitability and synaptic strength by acting at pre- and/or postsynaptic locations. Signalling to non-neuronal cells and an unexpected line of communication between endothelial cells and brain cells are also covered. Viewed from a mechanistic perspective, NO conforms to many of the rules governing more conventional neurotransmission, particularly of the metabotropic type, but stands out as being more economical and versatile, attributes that presumably account for its spectacular evolutionary success.
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Affiliation(s)
- John Garthwaite
- Wolfson Institute for Biomedical Research, University College London, Gower Street, London WCIE 6BT, UK.
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14
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Roy B, Halvey EJ, Garthwaite J. An enzyme-linked receptor mechanism for nitric oxide-activated guanylyl cyclase. J Biol Chem 2008; 283:18841-51. [PMID: 18463095 DOI: 10.1074/jbc.m801712200] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Nitric oxide (NO) exerts physiological effects by activating specialized receptors that are coupled to guanylyl cyclase activity, resulting in cGMP synthesis from GTP. Despite its widespread importance as a signal transduction pathway, the way it operates is still understood only in descriptive terms. The present work aimed to elucidate a formal mechanism for NO receptor activation and its modulation by GTP, ATP, and allosteric agents, such as YC-1 and BAY 41-2272. The model comprised a module in which NO, the nucleotides, and allosteric agents bind and the protein undergoes a conformational change, dovetailing with a catalytic module where GTP is converted to cGMP and pyrophosphate. Experiments on NO-activated guanylyl cyclase purified from bovine lung allowed values for all of the binding and isomerization constants to be derived. The catalytic module was a modified version of one describing the kinetics of adenylyl cyclase. The resulting enzyme-linked receptor mechanism faithfully reproduces all of the main functional properties of NO-activated guanylyl cyclase reported to date and provides a thermodynamically sound interpretation of those properties. With appropriate modification, it also replicates activation by carbon monoxide and the remarkable enhancement of that activity brought about by the allosteric agents. In addition, the mechanism enhances understanding of the behavior of the receptor in a cellular setting.
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Affiliation(s)
- Brijesh Roy
- Wolfson Institute for Biomedical Research, University College London, Gower Street, London WC1E 6BT, United Kingdom
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15
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Roy B, Garthwaite J. Nitric oxide activation of guanylyl cyclase in cells revisited. Proc Natl Acad Sci U S A 2006; 103:12185-90. [PMID: 16882726 PMCID: PMC1567716 DOI: 10.1073/pnas.0602544103] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Nitric oxide (NO) elicits physiological effects in cells largely by activating guanylyl cyclase (GC)-coupled receptors, leading to cGMP accumulation. Like other receptor-coupled effector mechanisms, NO stimulation of GC activity was previously considered to be a graded, concentration-dependent response, with deactivation following swiftly once the agonist disappeared. Recently, a new and unconventional mechanism has been proposed from experiments on purified protein [Cary, S. P. L., Winger, J. A. & Marletta, M. A. (2005) Proc. Natl. Acad. Sci. USA 102, 13064-13069]. It was concluded that GC in vivo will display a dual regulation by NO: a long-lasting tonic activity (10-20% of maximum) due to persistent occupation by NO of the heme binding site and phasic activity due to engagement of another unidentified, lower affinity site. The hypothesis was first tested by monitoring GC activity in rat platelets maintained in vitro and exposed to calibrated NO transients. The kinetics was as expected for a single binding site for NO (EC(50) = 10 nM), with activation and deactivation of enzyme activity conforming to the predictions of a simple receptor model. No tonic GC activity attributable to long-term NO binding was detected after exposure to the full range of active NO concentrations (peaking at 2-500 nM). Comparable results were obtained by using neural cells isolated from the cerebellum. After exposure to high NO concentrations, persistent GC activity could be recorded, but this activity was caused artifactually by secondary NO sources being formed in the medium. The new scheme for regulation of GC activity by NO is of doubtful relevance to cells.
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Affiliation(s)
- Brijesh Roy
- Wolfson Institute for Biomedical Research, University College London, Gower Street, London WC1E 6BT, United Kingdom
| | - John Garthwaite
- Wolfson Institute for Biomedical Research, University College London, Gower Street, London WC1E 6BT, United Kingdom
- To whom correspondence should be addressed. E-mail:
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Bidmon HJ, Mohlberg H, Habermann G, Buse E, Zilles K, Behrends S. Cerebellar localization of the NO-receptive soluble guanylyl cyclase subunits-alpha(2)/beta (1) in non-human primates. Cell Tissue Res 2006; 326:707-14. [PMID: 16819625 DOI: 10.1007/s00441-006-0246-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2005] [Accepted: 05/11/2006] [Indexed: 11/25/2022]
Abstract
Nitric-oxide-sensitive guanylyl cyclase (NO-sGC) plays a pivotal role in many second messenger cascades. Neurotransmission- and neuropathology-related changes in NO-sGC have been suggested. However, the cellular localization of NO-sGC in primate brains, including humans, remains unknown. Biochemical evidence has linked the alpha(2)-subunit of NO-sGC directly to neurotransmission in rodents. Here, we have used a recently characterized subunit-specific antibody for the localization of the alpha(2)-subunit on sections from the cerebelli of the common marmoset (Callithrix jacchus; New World monkey) and macaque monkeys (Macaca mulatta, M. fascicularis; Old World monkeys). In contrast to the more ubiquitous cytoplasmic presence of subunit-beta(1), the alpha(2)-subunit is mainly confined to the somato-dendritic membrane including the spines of the Purkinje cells. Only limited colocalization with presynaptically localized synaptophysin has been seen under our staining conditions, indicating a higher abundance of subunit-alpha(2) at the postsynaptic site. This localization indicates that subunit-alpha(2) links NO-sGC to neurotransmission, whereas subunit-beta(1) may act as a cytoplasmic regulator/activator by contributing to active heterodimer formation via translocation from the cytoplasm to the cell membrane. The last-mentioned action may be a prerequisite for generating nitric-oxide-dependent, subcellular, and postsynaptically localized cGMP signals along neuronal processes.
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Affiliation(s)
- Hans-J Bidmon
- C.& O. Vogt Institute of Brain Research, Bldg. 22.03, University St. 1, 40225 Düsseldorf, Germany.
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17
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Wang S, Paton JFR, Kasparov S. The challenge of real-time measurements of nitric oxide release in the brain. Auton Neurosci 2006; 126-127:59-67. [PMID: 16624633 DOI: 10.1016/j.autneu.2006.02.026] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2005] [Revised: 02/21/2006] [Accepted: 02/27/2006] [Indexed: 01/30/2023]
Abstract
Nitric oxide (NO) acts as a signalling molecule in the brain. NO has been implicated in a variety of central functions such as learning, plasticity and neurodegeneration. It is also involved in regulation of autonomic homeostasis at different levels of neuraxis including the nucleus tractus solitarii. In spite of the ample evidence for NO-mediated signalling many aspects of its mechanism of action the brain remain unknown largely due to the difficulties of NO detection in real time coupled with its unique ability to freely cross cellular membranes. Here we give a brief overview of the currently available options for NO detection in the brain (such as electrochemistry, fluorescent indicators, electron-paramagnetic resonance) and consider some of their limitations. We conclude that it would be extremely useful to develop a highly sensitive probe for NO detection with some kind of build-in amplification which would magnify the changes triggered by NO to allow its detection within microdomains of the brain tissue in real time.
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Affiliation(s)
- S Wang
- Department of Physiology, University of Bristol, Bristol BS8 1TD, UK
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18
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Marcoli M, Cervetto C, Paluzzi P, Guarnieri S, Raiteri M, Maura G. Nitric oxide-evoked glutamate release and cGMP production in cerebellar slices: control by presynaptic 5-HT1D receptors. Neurochem Int 2006; 49:12-9. [PMID: 16469416 DOI: 10.1016/j.neuint.2005.12.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2005] [Revised: 12/05/2005] [Accepted: 12/19/2005] [Indexed: 11/22/2022]
Abstract
We previously reported that pre- and postsynaptic 5-hydroxytryptamine (5-HT) receptors effectively control glutamatergic transmission in adult rat cerebellum. To investigate where 5-HT acts in the glutamate ionotropic receptors/nitric oxide/guanosine 3',5'-cyclic monophosphate (cGMP) pathway, in the present study 5-HT modulation of the cGMP response to the nitric oxide donor S-nitroso-penicillamine (SNAP) was studied in adult rat cerebellar slices. While cGMP elevation produced by high-micromolar SNAP was insensitive to 5-HT, 1 microM SNAP, expected to release nitric oxide in the low-nanomolar concentration range, elicited cGMP production and endogenous glutamate release both of which could be prevented by activating presynaptic 5-HT1D receptors. Released nitric oxide appeared responsible for cGMP production and glutamate release evoked by 1 microM SNAP, as both the effects were mimicked by the structurally unrelated nitric oxide donor 2-(N,N-diethylamino)-diazenolate-2-oxide (0.1 microM). Dependency of the 1 microM SNAP-evoked release of glutamate on external Ca2+, sensitivity to presynaptic release-regulating receptors and dependency on ionotropic glutamate receptor functioning, suggest that nitric oxide stimulates exocytotic-like, activity-dependent glutamate release. Activation of ionotropic glutamate receptors/nitric oxide synthase/guanylyl cyclase pathway by endogenously released glutamate was involved in the cGMP response to 1 microM SNAP, as blockade of NMDA/non-NMDA receptors, nitric oxide synthase or guanylyl cyclase, abolished the cGMP response. To conclude, in adult rat cerebellar slices low-nanomolar exogenous nitric oxide could facilitate glutamate exocytotic-like release possibly from parallel fibers that subsequently activated the glutamate ionotropic receptors/nitric oxide/cGMP pathway. Presynaptic 5-HT1D receptors could regulate the nitric oxide-evoked release of glutamate and subsequent cGMP production.
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Affiliation(s)
- Manuela Marcoli
- Department of Experimental Medicine, Pharmacology and Toxicology Section, University of Genoa, Viale Cembrano 4, Genoa, Italy
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19
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Pifarré P, García A, Mengod G. Species differences in the localization of soluble guanylyl cyclase subunits in monkey and rat brain. J Comp Neurol 2006; 500:942-57. [PMID: 17177259 DOI: 10.1002/cne.21241] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Nitric oxide (NO) exerts most of its physiological effects through activation of a predominantly soluble guanylyl cyclase (sGC). In mammalian cells sGC exists as a heterodimer of alpha and beta subunits. Currently, four subunits (alpha1, alpha2, beta1, and beta2) have been characterized. We used in situ hybridization with subunit-specific 33P-labeled oligonucleotide probes to compare the anatomical distribution of sGC subunit mRNAs in rat and monkey brains. Message for all subunits except beta2 was detected in both species. The sGC subunit showing the highest expression and widest distribution was beta1. High expression for all subunits was found in basal ganglia, olfactory system, hippocampus, cortex, and cerebellum. Minor species differences in the relative distribution of alpha subunits were observed. In general, the alpha1 message was more prominent in monkey brain and the alpha2 message in rat brain. This was more evident in limbic areas and cerebellar cortex. Some differences were also observed in subunit laminar distribution in cerebral cortex. The limited species differences in sGC subunit distribution suggest that in primates, as occurs in rodents, the NO-cGMP signaling pathway will be involved in important brain functions such as memory formation, sensory processing, and behavior.
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Affiliation(s)
- P Pifarré
- Institut de Biotecnologia i Biomedicina V. Villar Palasí and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Spain
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20
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Garthwaite G, Batchelor AM, Goodwin DA, Hewson AK, Leeming K, Ahmed Z, Cuzner ML, Garthwaite J. Pathological implications of iNOS expression in central white matter: an ex vivo study of optic nerves from rats with experimental allergic encephalomyelitis. Eur J Neurosci 2005; 21:2127-35. [PMID: 15869509 DOI: 10.1111/j.1460-9568.2005.04062.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Excessive nitric oxide (NO) production from the inducible isoform of nitric oxide synthase (iNOS) has been invoked as a causative factor in many neurodegenerative disorders, including multiple sclerosis. This hypothesis has been supported by in vitro studies showing that glial iNOS expression results in toxic NO concentrations (near 1 microm). To investigate the relevance of such findings, experiments were carried out ex vivo on optic nerves from rats with exacerbated experimental allergic encephalomyelitis, a model of multiple sclerosis. The nerves displayed characteristic immunopathology and expression of iNOS in macrophages and/or microglia and there was overt axonal damage in localized regions of the optic chiasm. The resulting NO levels in the optic nerve were sufficient to cause activation of guanylyl cyclase-coupled NO receptors, resulting in marked cGMP accumulation in axons throughout the nerve. Nevertheless, calibration of cGMP levels against those evoked by exogenous NO indicated that the nerves were not compromised metabolically and that their ambient NO concentration was only approximately 1 nm. Consistent with this observation, electrophysiological tests indicated that there was no ongoing malfunctioning of the type that can be elicited by high exogenous NO concentrations. It is concluded that, with iNOS expressed in physiological locations and levels, the tissue levels of NO remain at concentrations far lower than those shown to have toxic effects, despite continuous NO synthesis. The fact that NO can rise to much higher levels in dispersed cultures in vitro may be attributable to a deficiency in NO inactivation in such preparations.
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MESH Headings
- 1-Methyl-3-isobutylxanthine/pharmacology
- Action Potentials/drug effects
- Animals
- Arginine/pharmacology
- Biomarkers/metabolism
- CD11b Antigen/metabolism
- CD2 Antigens/metabolism
- Cyclic GMP/metabolism
- DEET/pharmacology
- Disease Models, Animal
- Dose-Response Relationship, Drug
- Electric Stimulation/methods
- Encephalomyelitis, Autoimmune, Experimental/chemically induced
- Encephalomyelitis, Autoimmune, Experimental/enzymology
- Encephalomyelitis, Autoimmune, Experimental/pathology
- Female
- Guanylate Cyclase/metabolism
- Guinea Pigs
- Hydrazines/pharmacology
- Immunohistochemistry/methods
- Macrophages/enzymology
- Macrophages/pathology
- Microscopy, Electron, Transmission/methods
- Myelin Basic Protein/metabolism
- Nitric Oxide/pharmacology
- Nitric Oxide Synthase/metabolism
- Nitric Oxide Synthase Type II
- Optic Chiasm/pathology
- Optic Chiasm/ultrastructure
- Optic Nerve/drug effects
- Optic Nerve/enzymology
- Optic Nerve/pathology
- Optic Nerve/ultrastructure
- Ornithine/analogs & derivatives
- Ornithine/pharmacology
- Phosphodiesterase Inhibitors/pharmacology
- Rats
- Rats, Inbred Lew
- Time Factors
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Affiliation(s)
- G Garthwaite
- The Wolfson Institute for Biomedical Research, University College London, Gower, Street, London WC1E 6BT, UK.
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21
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Kurylas AE, Ott SR, Schachtner J, Elphick MR, Williams L, Homberg U. Localization of nitric oxide synthase in the central complex and surrounding midbrain neuropils of the locust Schistocerca gregaria. J Comp Neurol 2005; 484:206-23. [PMID: 15736229 DOI: 10.1002/cne.20467] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Nitric oxide (NO), generated enzymatically by NO synthase (NOS), acts as an important signaling molecule in the nervous systems of vertebrates and invertebrates. In insects, NO has been implicated in development and in various aspects of sensory processing. To understand better the contribution of NO signaling to higher level brain functions, we analyzed the distribution of NOS in the midbrain of a model insect species, the locust Schistocerca gregaria, by using NADPH diaphorase (NADPHd) histochemistry after methanol/formalin fixation; results were validated by NOS immunohistochemistry. NADPHd yielded much higher sensitivity and resolution, but otherwise the two techniques resulted in corresponding labeling patterns throughout the brain, except for intense immunostaining but only weak NADPHd staining in median neurosecretory cells. About 470 neuronal cell bodies in the locust midbrain were NADPHd-positive positive, and nearly all major neuropil centers contained dense, sharply stained arborizations. We report several novel types of NOS-expressing neurons, including small ocellar interneurons and antennal sensory neurons that bypass the antennal lobe. Highly prominent labeling occurred in the central complex, a brain area involved in sky-compass orientation, and was analyzed in detail. Innervation by NOS-expressing fibers was most notable in the central body upper and lower divisions, the lateral accessory lobes, and the noduli. About 170 NADPHd-positive neurons contributed to this innervation, including five classes of tangential neuron, two systems of pontine neuron, and a system of columnar neurons. The results provide new insights into the neurochemical architecture of the central complex and suggest a prominent role for NO signaling in this brain area.
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Affiliation(s)
- Angela E Kurylas
- Fachbereich Biologie, Tierphysiologie, Philipps-Universität, D-35032 Marburg, Germany
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22
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André M, Latado H, Felley-Bosco E. Inducible nitric oxide synthase-dependent stimulation of PKGI and phosphorylation of VASP in human embryonic kidney cells. Biochem Pharmacol 2004; 69:595-602. [PMID: 15670578 DOI: 10.1016/j.bcp.2004.11.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2004] [Accepted: 11/09/2004] [Indexed: 10/26/2022]
Abstract
Inducible nitric oxide synthase (iNOS) production of nitric oxide (NO) has been mostly associated with so-called nitrosative stress or interaction with superoxide anion. However, recent investigations have indicated that, as for the other isoenzymes producing NO, guanylyl cyclase (GC) is a very sensitive target of iNOS activity. To further investigate this less explored signaling, the NO-cyclic guanosine 3'-5'-monophosphate (NO-cGMP)-induced vasodilator-stimulated phosphoprotein (VASP) phosphorylation on serine 239 was investigated in human embryonic kidney 293 cells (HEK cells). First, the expression and activity of alpha2 and beta1 NO-sensitive GC subunits was determined by Western blot analysis, reverse transcription-polymerase chain reaction and NO donors administration. Then, the expression of a functional cGMP-dependent protein kinase I (PKGI) was verified by addition of 8-Br-cGMP followed by determination of phosphorylation of VASP on serine 239. Finally, iNOS activation of this signaling pathway was characterized after transfection of HEK cells with human iNOS cDNA. Altogether our data show that iNOS-derived NO activates endogenous NO-sensitive GC and leads to VASP phosphorylation in HEK cells.
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Affiliation(s)
- Muriel André
- Pharmacology and Toxicology Department, Rue du Bugnon 27, 1005 Lausanne, Switzerland
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23
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Levy H, Twig G, Perlman I. Nitric oxide modulates the transfer function between cones and horizontal cells during changing conditions of ambient illumination. Eur J Neurosci 2004; 20:2963-74. [PMID: 15579150 DOI: 10.1111/j.1460-9568.2004.03758.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
It has been suggested that nitric oxide (NO) serves as a retinal neuromodulator, adjusting retinal function to changing conditions of adaptation. We tested this hypothesis in the intact turtle retina by recording the photoresponses of L-cones and L1-horizontal cells, while changing retinal NO level and background illumination. Raising the retinal level of NO, by adding an NO donor (sodium nitroprusside) or the precursor for NO synthesis (L-arginine), induced response augmentation in L-cones and L1-horizontal cells. Lowering retinal level of NO by adding L-NAME, an inhibitor of NO synthesis, reduced the amplitudes of the photoresponses in these retinal neurons. The transfer function between L-cones and L1-horizontal cells, constructed from the photoresponses of these cells, was modified by NO and by background lights. The nonlinear transfer function, characteristic of the dark-adapted retina, became linear and of low gain when the retinal NO level was increased or by increasing the level of ambient illumination. In contrast, inhibiting NO synthesis in the light-adapted retina induced nonlinearity in the cone-to-horizontal cell transfer function similar to that seen in the dark-adapted state. NADPH diaphorase histochemistry, conducted on isolated retinal cells, demonstrated activity in cone inner segments and distal process of Müller cells. These findings support the hypothesis that NO synthesis in the distal turtle retina is triggered by background illumination, and that NO acts to adjust the modes of visual information processing in the outer plexiform layer to the conditions required during continuous background illumination.
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Affiliation(s)
- H Levy
- The Ruth & Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology and the Rappaport Institute, P.O.Box 9649, Haifa 31096, Israel
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