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Haider AA, Rex TS, Wareham LK. cGMP Signaling in the Neurovascular Unit—Implications for Retinal Ganglion Cell Survival in Glaucoma. Biomolecules 2022; 12:biom12111671. [PMID: 36421684 PMCID: PMC9687235 DOI: 10.3390/biom12111671] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Revised: 11/07/2022] [Accepted: 11/09/2022] [Indexed: 11/16/2022] Open
Abstract
Glaucoma is a progressive age-related disease of the visual system and the leading cause of irreversible blindness worldwide. Currently, intraocular pressure (IOP) is the only modifiable risk factor for the disease, but even as IOP is lowered, the pathology of the disease often progresses. Hence, effective clinical targets for the treatment of glaucoma remain elusive. Glaucoma shares comorbidities with a multitude of vascular diseases, and evidence in humans and animal models demonstrates an association between vascular dysfunction of the retina and glaucoma pathology. Integral to the survival of retinal ganglion cells (RGCs) is functional neurovascular coupling (NVC), providing RGCs with metabolic support in response to neuronal activity. NVC is mediated by cells of the neurovascular unit (NVU), which include vascular cells, glial cells, and neurons. Nitric oxide-cyclic guanosine monophosphate (NO-cGMP) signaling is a prime mediator of NVC between endothelial cells and neurons, but emerging evidence suggests that cGMP signaling is also important in the physiology of other cells of the NVU. NO-cGMP signaling has been implicated in glaucomatous neurodegeneration in humans and mice. In this review, we explore the role of cGMP signaling in the different cell types of the NVU and investigate the potential links between cGMP signaling, breakdown of neurovascular function, and glaucoma pathology.
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2
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Ratko M, Habek N, Radmilović MD, Škokić S, Justić H, Barić A, Dugandžić A. Role of uroguanylin's signaling pathway in the development of ischemic stroke. Eur J Neurosci 2022; 56:3720-3737. [PMID: 35445449 PMCID: PMC9542124 DOI: 10.1111/ejn.15674] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Revised: 03/30/2022] [Accepted: 04/17/2022] [Indexed: 11/28/2022]
Abstract
Stroke is one of the leading causes of mortality and disability worldwide. By affecting bradykinin function, activation of guanylate cyclase (GC)‐A has been shown to have a neuroprotective effect after ischaemic stroke, whereas the same has not been confirmed for GC‐B; therefore, we aimed to determine the possible role of GC‐C and its agonist, uroguanylin (UGN), in the development of stroke. In this study, middle cerebral artery occlusion (MCAO) was performed on wild‐type (WT), GC‐C KO and UGN KO mice. MR images were acquired before and 24 h after MCAO. On brain slices 48 h after MCAO, the Ca2+ response to UGN stimulation was recorded. Our results showed that the absence of GC‐C in GC‐C KO mice resulted in the development of smaller ischaemic lesions compared with WT littermates, which is an opposite effect compared with the effects of GC‐A agonists on brain lesions. WT and UGN KO animals showed a stronger Ca2+ response upon UGN stimulation in astrocytes of the peri‐ischaemic cerebral cortex compared with the same cortical region of the unaffected contralateral hemisphere. This stronger activation was not observed in GC‐C KO animals, which may be the reason for smaller lesion development in GC‐C KO mice. The reason why GC‐C might affect Ca2+ signalling in peri‐ischaemic astrocytes is that GC‐C is expressed in these cells after MCAO, whereas under normoxic conditions, it is expressed mainly in cortical neurons. Stronger activation of the Ca2+‐dependent signalling pathway could lead to the stronger activation of the Na+/H+ exchanger, tissue acidification and neuronal death.
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Affiliation(s)
- Martina Ratko
- Croatian Institute for Brain Research, School of Medicine, University of Zagreb, Zagreb, Croatia.,Centre of Excellence for Basic, Clinical and Translational Neuroscience, School of Medicine, University of Zagreb, Zagreb, Croatia
| | - Nikola Habek
- Croatian Institute for Brain Research, School of Medicine, University of Zagreb, Zagreb, Croatia
| | | | - Siniša Škokić
- Croatian Institute for Brain Research, School of Medicine, University of Zagreb, Zagreb, Croatia
| | - Helena Justić
- Croatian Institute for Brain Research, School of Medicine, University of Zagreb, Zagreb, Croatia
| | - Anja Barić
- Croatian Institute for Brain Research, School of Medicine, University of Zagreb, Zagreb, Croatia
| | - Aleksandra Dugandžić
- Croatian Institute for Brain Research, School of Medicine, University of Zagreb, Zagreb, Croatia.,Centre of Excellence for Basic, Clinical and Translational Neuroscience, School of Medicine, University of Zagreb, Zagreb, Croatia.,Department of Physiology, School of Medicine, University of Zagreb, Zagreb, Croatia
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3
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Zhou G, Wang Z, Han S, Chen X, Li Z, Hu X, Li Y, Gao J. Multifaceted Roles of cAMP Signaling in the Repair Process of Spinal Cord Injury and Related Combination Treatments. Front Mol Neurosci 2022; 15:808510. [PMID: 35283731 PMCID: PMC8904388 DOI: 10.3389/fnmol.2022.808510] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Accepted: 01/26/2022] [Indexed: 01/03/2023] Open
Abstract
Spinal cord injury (SCI) results in multiple pathophysiological processes, including blood–spinal cord barrier disruption, hemorrhage/ischemia, oxidative stress, neuroinflammation, scar formation, and demyelination. These responses eventually lead to severe tissue destruction and an inhibitory environment for neural regeneration.cAMP signaling is vital for neurite outgrowth and axonal guidance. Stimulating intracellular cAMP activity significantly promotes neuronal survival and axonal regrowth after SCI.However, neuronal cAMP levels in adult CNS are relatively low and will further decrease after injury. Targeting cAMP signaling has become a promising strategy for neural regeneration over the past two decades. Furthermore, studies have revealed that cAMP signaling is involved in the regulation of glial cell function in the microenvironment of SCI, including macrophages/microglia, reactive astrocytes, and oligodendrocytes. cAMP-elevating agents in the post-injury milieu increase the cAMP levels in both neurons and glial cells and facilitate injury repair through the interplay between neurons and glial cells and ultimately contribute to better morphological and functional outcomes. In recent years, combination treatments associated with cAMP signaling have been shown to exert synergistic effects on the recovery of SCI. Agents carried by nanoparticles exhibit increased water solubility and capacity to cross the blood–spinal cord barrier. Implanted bioscaffolds and injected hydrogels are potential carriers to release agents locally to avoid systemic side effects. Cell transplantation may provide permissive matrices to synergize with the cAMP-enhanced growth capacity of neurons. cAMP can also induce the oriented differentiation of transplanted neural stem/progenitor cells into neurons and increase the survival rate of cell grafts. Emerging progress focused on cAMP compartmentation provides researchers with new perspectives to understand the complexity of downstream signaling, which may facilitate the clinical translation of strategies targeting cAMP signaling for SCI repair.
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Affiliation(s)
- Gang Zhou
- Department of Neurosurgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Zhiyan Wang
- Plastic Surgery Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Shiyuan Han
- Department of Neurosurgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Xiaokun Chen
- Department of Neurosurgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Zhimin Li
- Department of Neurosurgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Xianghui Hu
- Department of Neurosurgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Yongning Li
- Department of Neurosurgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
- Department of International Medical Service, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Jun Gao
- Department of Neurosurgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
- *Correspondence: Jun Gao
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4
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Lee H, Kang SW, Jeong H, Kwon JT, Kim YO, Kim HJ. Alteration in Cngb1 Expression upon Maternal Immune Activation in a Mouse Model and Its Possible Association with Schizophrenia Susceptibility. CLINICAL PSYCHOPHARMACOLOGY AND NEUROSCIENCE 2021; 19:618-627. [PMID: 34690117 PMCID: PMC8553526 DOI: 10.9758/cpn.2021.19.4.618] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 10/20/2020] [Accepted: 11/11/2020] [Indexed: 11/26/2022]
Abstract
Objective The cyclic nucleotide-gated channel (Cng) regulates synaptic efficacy in brain neurons by modulating Ca2+ levels in response to changes in cyclic nucleotide concentrations. This study investigated whether the expression of Cng channel, cyclic nucleotide-gated channel subunit beta 1 (Cngb1) exhibited any relationship with the pathophysiology of schizophrenia in an animal model and whether genetic polymorphisms of the human gene were associated with the progression of schizophrenia in a Korean population. Methods We investigated whether Cngb1 expression was related to psychiatric disorders in a mouse model of schizophrenia induced by maternal immune activation. A case-control study was conducted of 275 schizophrenia patients and 410 controls with single-nucleotide polymorphisms (SNPs) in the 5′-near region of CNGB1. Results Cngb1 expression was decreased in the prefrontal cortex in the mouse model. Furthermore, the genotype frequency of a SNP (rs3756314) of CNGB1 was associated with the risk of schizophrenia. Conclusion Our results suggest that CNGB1 might be associated with schizophrenia susceptibility and maternal immune activation. Consequently, it is hypothesized that CNGB1 may be involved in the pathophysiology of schizophrenia.
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Affiliation(s)
- Hwayoung Lee
- Department of Clinical Pharmacology, Soonchunhyang University College of Medicine, Cheonan, Korea
| | - Sung Wook Kang
- Cardiovascular Center of Excellence, Louisiana State University Health Science Center, New Orleans, LA, USA
| | - Hyeonjung Jeong
- Department of Clinical Pharmacology, Soonchunhyang University College of Medicine, Cheonan, Korea
| | - Jun-Tack Kwon
- Department of Clinical Pharmacology, Soonchunhyang University College of Medicine, Cheonan, Korea
| | - Young Ock Kim
- Department of Clinical Pharmacology, Soonchunhyang University College of Medicine, Cheonan, Korea
| | - Hak-Jae Kim
- Department of Clinical Pharmacology, Soonchunhyang University College of Medicine, Cheonan, Korea
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5
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Dynamic expression of homeostatic ion channels in differentiated cortical astrocytes in vitro. Pflugers Arch 2021; 474:243-260. [PMID: 34734327 PMCID: PMC8766406 DOI: 10.1007/s00424-021-02627-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 09/02/2021] [Accepted: 09/24/2021] [Indexed: 11/16/2022]
Abstract
The capacity of astrocytes to adapt their biochemical and functional features upon physiological and pathological stimuli is a fundamental property at the basis of their ability to regulate the homeostasis of the central nervous system (CNS). It is well known that in primary cultured astrocytes, the expression of plasma membrane ion channels and transporters involved in homeostatic tasks does not closely reflect the pattern observed in vivo. The individuation of culture conditions that promote the expression of the ion channel array found in vivo is crucial when aiming at investigating the mechanisms underlying their dynamics upon various physiological and pathological stimuli. A chemically defined medium containing growth factors and hormones (G5) was previously shown to induce the growth, differentiation, and maturation of primary cultured astrocytes. Here we report that under these culture conditions, rat cortical astrocytes undergo robust morphological changes acquiring a multi-branched phenotype, which develops gradually during the 2-week period of culturing. The shape changes were paralleled by variations in passive membrane properties and background conductance owing to the differential temporal development of inwardly rectifying chloride (Cl−) and potassium (K+) currents. Confocal and immunoblot analyses showed that morphologically differentiated astrocytes displayed a large increase in the expression of the inward rectifier Cl− and K+ channels ClC-2 and Kir4.1, respectively, which are relevant ion channels in vivo. Finally, they exhibited a large diminution of the intermediate filaments glial fibrillary acidic protein (GFAP) and vimentin which are upregulated in reactive astrocytes in vivo. Taken together the data indicate that long-term culturing of cortical astrocytes in this chemical-defined medium promotes a quiescent functional phenotype. This culture model could aid to address the regulation of ion channel expression involved in CNS homeostasis in response to physiological and pathological challenges.
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Howard N, Hussain A. The Fundamental Code Unit of the Brain: Towards a New Model for Cognitive Geometry. Cognit Comput 2018; 10:426-436. [PMID: 29881471 PMCID: PMC5971038 DOI: 10.1007/s12559-017-9538-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2017] [Accepted: 09/06/2017] [Indexed: 11/29/2022]
Abstract
This paper discusses the problems arising from the multidisciplinary nature of cognitive research and the need to conceptually unify insights from multiple fields into the phenomena that drive cognition. Specifically, the Fundamental Code Unit (FCU) is proposed as a means to better quantify the intelligent thought process at multiple levels of analysis. From the linguistic and behavioral output, FCU produces to the chemical and physical processes within the brain that drive it. The proposed method efficiently model the most complex decision-making process performed by the brain.
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7
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Mastrodonato A, Barbati SA, Leone L, Colussi C, Gironi K, Rinaudo M, Piacentini R, Denny CA, Grassi C. Olfactory memory is enhanced in mice exposed to extremely low-frequency electromagnetic fields via Wnt/β-catenin dependent modulation of subventricular zone neurogenesis. Sci Rep 2018; 8:262. [PMID: 29321633 PMCID: PMC5762682 DOI: 10.1038/s41598-017-18676-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Accepted: 12/15/2017] [Indexed: 12/03/2022] Open
Abstract
Exposure to extremely low-frequency electromagnetic fields (ELFEF) influences the expression of key target genes controlling adult neurogenesis and modulates hippocampus-dependent memory. Here, we assayed whether ELFEF stimulation affects olfactory memory by modulating neurogenesis in the subventricular zone (SVZ) of the lateral ventricle, and investigated the underlying molecular mechanisms. We found that 30 days after the completion of an ELFEF stimulation protocol (1 mT; 50 Hz; 3.5 h/day for 12 days), mice showed enhanced olfactory memory and increased SVZ neurogenesis. These effects were associated with upregulated expression of mRNAs encoding for key regulators of adult neurogenesis and were mainly dependent on the activation of the Wnt pathway. Indeed, ELFEF stimulation increased Wnt3 mRNA expression and nuclear localization of its downstream target β-catenin. Conversely, inhibition of Wnt3 by Dkk-1 prevented ELFEF-induced upregulation of neurogenic genes and abolished ELFEF’s effects on olfactory memory. Collectively, our findings suggest that ELFEF stimulation increases olfactory memory via enhanced Wnt/β-catenin signaling in the SVZ and point to ELFEF as a promising tool for enhancing SVZ neurogenesis and olfactory function.
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Affiliation(s)
- Alessia Mastrodonato
- Università Cattolica del Sacro Cuore, Institute of Human Physiology, Rome, 00168, Italy.,Columbia University, Department of Psychiatry, New York, NY, 10032, USA.,Research Foundation for Mental Hygiene Inc. (RFMH), Division of Integrative Neuroscience, New York State Psychiatric Institute (NYSPI), New York, NY, 10032, USA
| | | | - Lucia Leone
- Università Cattolica del Sacro Cuore, Institute of Human Physiology, Rome, 00168, Italy
| | - Claudia Colussi
- CNR, Institute of Cell Biology and Neurobiology, Monterotondo (RM), 00015, Italy
| | - Katia Gironi
- Università Cattolica del Sacro Cuore, Institute of Human Physiology, Rome, 00168, Italy
| | - Marco Rinaudo
- Università Cattolica del Sacro Cuore, Institute of Human Physiology, Rome, 00168, Italy
| | - Roberto Piacentini
- Università Cattolica del Sacro Cuore, Institute of Human Physiology, Rome, 00168, Italy
| | - Christine A Denny
- Columbia University, Department of Psychiatry, New York, NY, 10032, USA.,Research Foundation for Mental Hygiene Inc. (RFMH), Division of Integrative Neuroscience, New York State Psychiatric Institute (NYSPI), New York, NY, 10032, USA
| | - Claudio Grassi
- Università Cattolica del Sacro Cuore, Institute of Human Physiology, Rome, 00168, Italy. .,Fondazione Policlinico Universitario A. Gemelli, Rome, 00168, Italy.
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8
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Piacentini R, Puma DDL, Mainardi M, Lazzarino G, Tavazzi B, Arancio O, Grassi C. Reduced gliotransmitter release from astrocytes mediates tau-induced synaptic dysfunction in cultured hippocampal neurons. Glia 2017; 65:1302-1316. [PMID: 28519902 PMCID: PMC5520670 DOI: 10.1002/glia.23163] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Revised: 04/13/2017] [Accepted: 04/18/2017] [Indexed: 01/19/2023]
Abstract
Tau is a microtubule-associated protein exerting several physiological functions in neurons. In Alzheimer's disease (AD) misfolded tau accumulates intraneuronally and leads to axonal degeneration. However, tau has also been found in the extracellular medium. Recent studies indicated that extracellular tau uploaded from neurons causes synaptic dysfunction and contributes to tau pathology propagation. Here we report novel evidence that extracellular tau oligomers are abundantly and rapidly accumulated in astrocytes where they disrupt intracellular Ca2+ signaling and Ca2+ -dependent release of gliotransmitters, especially ATP. Consequently, synaptic vesicle release, the expression of pre- and postsynaptic proteins, and mEPSC frequency and amplitude were reduced in neighboring neurons. Notably, we found that tau uploading from astrocytes required the amyloid precursor protein, APP. Collectively, our findings suggests that astrocytes play a critical role in the synaptotoxic effects of tau via reduced gliotransmitter availability, and that astrocytes are major determinants of tau pathology in AD.
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Affiliation(s)
- Roberto Piacentini
- Institute of Human Physiology, Medical School, Università Cattolica, Largo F. Vito 1, 00168, Rome, Italy
| | - Domenica Donatella Li Puma
- Institute of Human Physiology, Medical School, Università Cattolica, Largo F. Vito 1, 00168, Rome, Italy
| | - Marco Mainardi
- Institute of Human Physiology, Medical School, Università Cattolica, Largo F. Vito 1, 00168, Rome, Italy
| | - Giacomo Lazzarino
- Institute of Biochemistry and Clinical Biochemistry, Medical School, Università Cattolica, Largo F. Vito 1, 00168, Rome, Italy
| | - Barbara Tavazzi
- Institute of Biochemistry and Clinical Biochemistry, Medical School, Università Cattolica, Largo F. Vito 1, 00168, Rome, Italy
| | - Ottavio Arancio
- Department of Pathology and Cell Biology and Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University, New York, 630 W 168th St., NY 10032 USA
| | - Claudio Grassi
- Institute of Human Physiology, Medical School, Università Cattolica, Largo F. Vito 1, 00168, Rome, Italy
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Barbati SA, Colussi C, Bacci L, Aiello A, Re A, Stigliano E, Isidori AM, Grassi C, Pontecorvi A, Farsetti A, Gaetano C, Nanni S. Transcription Factor CREM Mediates High Glucose Response in Cardiomyocytes and in a Male Mouse Model of Prolonged Hyperglycemia. Endocrinology 2017; 158:2391-2405. [PMID: 28368536 DOI: 10.1210/en.2016-1960] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Accepted: 03/16/2017] [Indexed: 01/31/2023]
Abstract
This study aims at investigating the epigenetic landscape of cardiomyocytes exposed to elevated glucose levels. High glucose (30 mM) for 72 hours determined some epigenetic changes in mouse HL-1 and rat differentiated H9C2 cardiomyocytes including upregulation of class I and III histone deacetylase protein levels and activity, inhibition of histone acetylase p300 activity, increase in histone H3 lysine 27 trimethylation, and reduction in H3 lysine 9 acetylation. Gene expression analysis focused on cardiotoxicity revealed that high glucose induced markers associated with tissue damage, fibrosis, and cardiac remodeling such as Nexilin (NEXN), versican, cyclic adenosine 5'-monophosphate-responsive element modulator (CREM), and adrenoceptor α2A (ADRA2). Notably, the transcription factor CREM was found to be important in the regulation of cardiotoxicity-associated genes as assessed by specific small interfering RNA and chromatin immunoprecipitation experiments. In CD1 mice, made hyperglycemic by streptozotoicin (STZ) injection, cardiac structural alterations were evident at 6 months after STZ treatment and were associated with a significant increase of H3 lysine 27 trimethylation and reduction of H3 lysine 9 acetylation. Consistently, NEXN, CREM, and ADRA2 expression was significantly induced at the RNA and protein levels. Confocal microscopy analysis of NEXN localization showed this protein irregularly distributed along the sarcomeres in the heart of hyperglycemic mice. This evidence suggested a structural alteration of cardiac Z-disk with potential consequences on contractility. In conclusion, high glucose may alter the epigenetic landscape of cardiac cells. Sildenafil, restoring guanosine 3', 5'-cyclic monophosphate levels, counteracted the increase of CREM and NEXN, providing a protective effect in the presence of hyperglycemia.
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Affiliation(s)
- Saviana A Barbati
- Institute of Human Physiology, Università Cattolica di Roma, 00168 Rome, Italy
- Institute of Medical Pathology, Università Cattolica di Roma, 00168 Rome, Italy
| | - Claudia Colussi
- Institute of Medical Pathology, Università Cattolica di Roma, 00168 Rome, Italy
- Institute of Cell Biology and Neurobiology, National Research Council, 00143 Rome, Italy
| | - Lorenza Bacci
- Institute of Medical Pathology, Università Cattolica di Roma, 00168 Rome, Italy
| | - Aurora Aiello
- Institute of Medical Pathology, Università Cattolica di Roma, 00168 Rome, Italy
- Institute of Cell Biology and Neurobiology, National Research Council, 00143 Rome, Italy
| | - Agnese Re
- Institute of Cell Biology and Neurobiology, National Research Council, 00143 Rome, Italy
| | - Egidio Stigliano
- Department of Histopathology, Università Cattolica di Roma, 00168 Rome, Italy
| | - Andrea M Isidori
- Department of Experimental Medicine, "Sapienza" University, 00161 Rome, Italy
| | - Claudio Grassi
- Institute of Human Physiology, Università Cattolica di Roma, 00168 Rome, Italy
| | - Alfredo Pontecorvi
- Institute of Medical Pathology, Università Cattolica di Roma, 00168 Rome, Italy
| | - Antonella Farsetti
- Institute of Cell Biology and Neurobiology, National Research Council, 00143 Rome, Italy
- Medicine Clinic III, Goethe University Frankfurt, 60590 Frankfurt am Main, Germany
| | - Carlo Gaetano
- Medicine Clinic III, Division of Cardiovascular Epigenetics, Goethe University Frankfurt, 60590 Frankfurt am Main, Germany
| | - Simona Nanni
- Institute of Medical Pathology, Università Cattolica di Roma, 00168 Rome, Italy
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10
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Gonçalves I, Hubbard PC, Tomás J, Quintela T, Tavares G, Caria S, Barreiros D, Santos CRA. 'Smelling' the cerebrospinal fluid: olfactory signaling molecules are expressed in and mediate chemosensory signaling from the choroid plexus. FEBS J 2016; 283:1748-66. [PMID: 26934374 DOI: 10.1111/febs.13700] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Revised: 02/13/2016] [Accepted: 02/29/2016] [Indexed: 01/03/2023]
Abstract
The olfactory-type signaling machinery has been known to be involved not only in odorant detection but also in other tissues with unsuspected sensory roles. As a barrier, the choroid plexus (CP) is an active participant in the monitoring of the cerebrospinal fluid (CSF), promptly responding to alterations in its composition. We hypothesized that olfactory signaling could be active in CP, contributing to the surveillance of the CSF composition. We determined the mRNA and protein expression of the major components of the olfactory transduction pathway in the rat CP, including odorant receptors, the olfactory G-protein (Gαolf), adenylate cyclase 3 and cyclic nucleotide-gated channel 2. The functionality of the transduction pathway and the intracellular mechanisms involved were analyzed by DC field potential recording electrophysiological analysis, in an ex vivo CP-brain setup, using polyamines as stimuli and blockers of the downstream signaling pathways. Concentration-dependent responses were obtained for the polyamines studied (cadaverine, putrescine, spermine and spermidine), all known to be present in the CSF. Transfection of a CP epithelial cell line with siRNA against Gαolf effectively knocked down protein expression and reduced the CP cells' response to spermine. Thus, the key components of the olfactory chemosensory apparatus are present and are functional in murine CP, and polyamines seem to trigger both the cAMP and the phospholipase C-inositol 1,4,5-trisphosphate pathways. Olfactory-like chemosensory signaling may be an essential component of the CP chemical surveillance apparatus to detect alterations in the CSF composition, and to elicit responses to modulate and maintain brain homeostasis.
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Affiliation(s)
- Isabel Gonçalves
- CICS-UBI - Health Sciences Research Centre, University of Beira Interior, Covilhã, Portugal
| | - Peter C Hubbard
- CCMAR - Centro de Ciências do Mar, Universidade do Algarve, Faro, Portugal
| | - Joana Tomás
- CICS-UBI - Health Sciences Research Centre, University of Beira Interior, Covilhã, Portugal
| | - Telma Quintela
- CICS-UBI - Health Sciences Research Centre, University of Beira Interior, Covilhã, Portugal
| | - Gabriela Tavares
- CICS-UBI - Health Sciences Research Centre, University of Beira Interior, Covilhã, Portugal
| | - Sandra Caria
- CICS-UBI - Health Sciences Research Centre, University of Beira Interior, Covilhã, Portugal
| | - Daniela Barreiros
- CICS-UBI - Health Sciences Research Centre, University of Beira Interior, Covilhã, Portugal
| | - Cecília R A Santos
- CICS-UBI - Health Sciences Research Centre, University of Beira Interior, Covilhã, Portugal
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11
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In vitro cardiomyocyte differentiation of umbilical cord blood cells: crucial role for c-kit+ cells. Cytotherapy 2015; 17:1627-37. [DOI: 10.1016/j.jcyt.2015.07.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2015] [Revised: 07/16/2015] [Accepted: 07/20/2015] [Indexed: 11/22/2022]
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12
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Scala F, Fusco S, Ripoli C, Piacentini R, Li Puma DD, Spinelli M, Laezza F, Grassi C, D'Ascenzo M. Intraneuronal Aβ accumulation induces hippocampal neuron hyperexcitability through A-type K(+) current inhibition mediated by activation of caspases and GSK-3. Neurobiol Aging 2015; 36:886-900. [PMID: 25541422 PMCID: PMC4801354 DOI: 10.1016/j.neurobiolaging.2014.10.034] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2014] [Revised: 10/14/2014] [Accepted: 10/24/2014] [Indexed: 11/20/2022]
Abstract
Amyloid β-protein (Aβ) pathologies have been linked to dysfunction of excitability in neurons of the hippocampal circuit, but the molecular mechanisms underlying this process are still poorly understood. Here, we applied whole-cell patch-clamp electrophysiology to primary hippocampal neurons and show that intracellular Aβ42 delivery leads to increased spike discharge and action potential broadening through downregulation of A-type K(+) currents. Pharmacologic studies showed that caspases and glycogen synthase kinase 3 (GSK-3) activation are required for these Aβ42-induced effects. Extracellular perfusion and subsequent internalization of Aβ42 increase spike discharge and promote GSK-3-dependent phosphorylation of the Kv4.2 α-subunit, a molecular determinant of A-type K(+) currents, at Ser-616. In acute hippocampal slices derived from an adult triple-transgenic Alzheimer's mouse model, characterized by endogenous intracellular accumulation of Aβ42, CA1 pyramidal neurons exhibit hyperexcitability accompanied by increased phosphorylation of Kv4.2 at Ser-616. Collectively, these data suggest that intraneuronal Aβ42 accumulation leads to an intracellular cascade culminating into caspases activation and GSK-3-dependent phosphorylation of Kv4.2 channels. These findings provide new insights into the toxic mechanisms triggered by intracellular Aβ42 and offer potentially new therapeutic targets for Alzheimer's disease treatment.
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Affiliation(s)
- Federico Scala
- Institute of Human Physiology, Medical School, Università Cattolica, Rome, Italy
| | - Salvatore Fusco
- Institute of Human Physiology, Medical School, Università Cattolica, Rome, Italy
| | - Cristian Ripoli
- Institute of Human Physiology, Medical School, Università Cattolica, Rome, Italy
| | - Roberto Piacentini
- Institute of Human Physiology, Medical School, Università Cattolica, Rome, Italy
| | | | - Matteo Spinelli
- Institute of Human Physiology, Medical School, Università Cattolica, Rome, Italy
| | - Fernanda Laezza
- Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, TX, USA
| | - Claudio Grassi
- Institute of Human Physiology, Medical School, Università Cattolica, Rome, Italy.
| | - Marcello D'Ascenzo
- Institute of Human Physiology, Medical School, Università Cattolica, Rome, Italy.
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Fetoni AR, Eramo SLM, Paciello F, Rolesi R, Podda MV, Troiani D, Paludetti G. Curcuma longa (curcumin) decreases in vivo cisplatin-induced ototoxicity through heme oxygenase-1 induction. Otol Neurotol 2015; 35:e169-77. [PMID: 24608370 DOI: 10.1097/mao.0000000000000302] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
HYPOTHESIS To investigate whether curcumin may have in vivo protective effects against cisplatin ototoxicity by its direct scavenger activity and/or by curcumin-mediated upregulation of HO-1. BACKGROUND Cisplatin-induced ototoxicity is a major dose-limiting side effect in anticancer chemotherapy. A protective approach to decrease cisplatin ototoxicity without compromising its therapeutic efficacy remains a critical goal for anticancer therapy. Recent evidences indicate that curcumin exhibits antioxidant, anti-inflammatory, and chemosensitizer activities. METHODS In male adult Wistar rats, a curcumin dose of 200 mg/kg, selected from a dose-response curve, was injected 1 hour before cisplatin administration and once daily for the following 3 days. A single dose of cisplatin (16 mg/kg) was administered intraperitoneally. Rats were divided as follows: 1) control, 2) curcumin control, 3) vehicle control, 4) cisplatin, 5) cisplatin+ vehicle, and 6) curcumin+cisplatin. ABRs were measured before and at Days 3 and 5 after cisplatin administration. Rhodamine-phalloidin staining, 4-hydroxy-2-nonenal and heme-oxigenase-1 immunostainings, and Western blot analyses were performed to assess and quantify OHC loss, lipid peroxidation, and the endogenous response to cisplatin-induced damage and to curcumin protection. RESULTS Curcumin treatment attenuated hearing loss induced by cisplatin, increased OHC survival, decreased 4-HNE expression, and increased HO-1 expression. CONCLUSION This preclinical study demonstrates that systemic curcumin attenuates ototoxicity and provides molecular evidence for a role of HO-1 as an additional mediator in attenuating cisplatin-induced damage.
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Affiliation(s)
- Anna R Fetoni
- Department of Otolaryngology, Head and Neck Surgery; Institute of Human Physiology, Catholic University of Rome, Rome, Italy
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14
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Intracellular accumulation of amyloid-β (Aβ) protein plays a major role in Aβ-induced alterations of glutamatergic synaptic transmission and plasticity. J Neurosci 2014; 34:12893-903. [PMID: 25232124 DOI: 10.1523/jneurosci.1201-14.2014] [Citation(s) in RCA: 83] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Intracellular accumulation of amyloid-β (Aβ) protein has been proposed as an early event in AD pathogenesis. In patients with mild cognitive impairment, intraneuronal Aβ immunoreactivity was found especially in brain regions critically involved in the cognitive deficits of AD. Although a large body of evidence demonstrates that Aβ42 accumulates intraneuronally ((in)Aβ), the action and the role of Aβ42 buildup on synaptic function have been poorly investigated. Here, we demonstrate that basal synaptic transmission and LTP were markedly depressed following Aβ42 injection into the neuron through the patch pipette. Control experiments performed with the reverse peptide (Aβ42-1) allowed us to exclude that the effects of (in)Aβ depended on changes in oncotic pressure. To further investigate (in)Aβ synaptotoxicity we used an Aβ variant harboring oxidized methionine in position 35 that does not cross the neuronal plasma membrane and is not uploaded from the extracellular space. This Aβ42 variant had no effects on synaptic transmission and plasticity when applied extracellularly, but induced synaptic depression and LTP inhibition after patch-pipette dialysis. Finally, the injection of an antibody raised against human Aβ42 (6E10) in CA1 pyramidal neurons of mouse hippocampal brain slices and autaptic microcultures did not, per se, significantly affect LTP and basal synaptic transmission, but it protected against the toxic effects of extracellular Aβ42. Collectively, these findings suggest that Aβ42-induced impairment of glutamatergic synaptic function depends on its internalization and intracellular accumulation thus paving the way to a systemic proteomic analysis of intracellular targets/partners of Aβ42.
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15
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Maulucci G, Troiani D, Eramo SLM, Paciello F, Podda MV, Paludetti G, Papi M, Maiorana A, Palmieri V, De Spirito M, Fetoni AR. Time evolution of noise induced oxidation in outer hair cells: role of NAD(P)H and plasma membrane fluidity. Biochim Biophys Acta Gen Subj 2014; 1840:2192-202. [PMID: 24735797 DOI: 10.1016/j.bbagen.2014.04.005] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2014] [Revised: 03/25/2014] [Accepted: 04/07/2014] [Indexed: 01/24/2023]
Abstract
BACKGROUND Noise exposure impairs outer hair cells (OHCs). The common basis for OHC dysfunction and loss by acoustic over-stimulation is represented by reactive oxygen species (ROS) overload that may affect the membrane structural organization through generation of lipid peroxidation. METHODS Here we investigated in OHC different functional zones the mechanisms linking metabolic functional state (NAD(P)H intracellular distribution) to the generation of lipid peroxides and to the physical state of membranes by two photon fluorescence microscopy. RESULTS In OHCs of control animals, a more oxidized NAD(P)H redox state is associated to a less fluid plasma membrane structure. Acoustic trauma induces a topologically differentiated NAD(P)H oxidation in OHC rows, which is damped between 1 and 6h. Peroxidation occurs after ~4h from noise insult, while ROS are produced in the first 0.2h and damage cells for a period of time after noise exposure has ended (~7.5h) when a decrease of fluidity of OHC plasma membrane occurs. OHCs belonging to inner rows, characterized by a lower metabolic activity with respect to other rows, show less severe metabolic impairment. CONCLUSIONS Our data indicate that plasma membrane fluidity is related to NAD(P)H redox state and lipid peroxidation in hair cells. GENERAL SIGNIFICANCE Our results could pave the way for therapeutic intervention targeting the onset of redox umbalance.
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Affiliation(s)
| | - Diana Troiani
- Istituto di Fisiologia, Università Cattolica (UCSC), Roma, Italy.
| | | | - Fabiola Paciello
- Dipartimento di Scienze Chirurgiche per le patologie della testa e del collo, Università Cattolica (UCSC), Roma, Italy
| | | | - Gaetano Paludetti
- Dipartimento di Scienze Chirurgiche per le patologie della testa e del collo, Università Cattolica (UCSC), Roma, Italy
| | | | | | | | | | - Anna Rita Fetoni
- Dipartimento di Scienze Chirurgiche per le patologie della testa e del collo, Università Cattolica (UCSC), Roma, Italy
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16
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Leone L, Fusco S, Mastrodonato A, Piacentini R, Barbati SA, Zaffina S, Pani G, Podda MV, Grassi C. Epigenetic Modulation of Adult Hippocampal Neurogenesis by Extremely Low-Frequency Electromagnetic Fields. Mol Neurobiol 2014; 49:1472-86. [DOI: 10.1007/s12035-014-8650-8] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2013] [Accepted: 01/22/2014] [Indexed: 12/22/2022]
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17
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Corvino V, Marchese E, Podda MV, Lattanzi W, Giannetti S, Di Maria V, Cocco S, Grassi C, Michetti F, Geloso MC. The neurogenic effects of exogenous neuropeptide Y: early molecular events and long-lasting effects in the hippocampus of trimethyltin-treated rats. PLoS One 2014; 9:e88294. [PMID: 24516629 PMCID: PMC3917853 DOI: 10.1371/journal.pone.0088294] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2013] [Accepted: 01/05/2014] [Indexed: 01/08/2023] Open
Abstract
Modulation of endogenous neurogenesis is regarded as a promising challenge in neuroprotection. In the rat model of hippocampal neurodegeneration obtained by Trimethyltin (TMT) administration (8 mg/kg), characterised by selective pyramidal cell loss, enhanced neurogenesis, seizures and cognitive impairment, we previously demonstrated a proliferative role of exogenous neuropeptide Y (NPY), on dentate progenitors in the early phases of neurodegeneration. To investigate the functional integration of newly-born neurons, here we studied in adult rats the long-term effects of intracerebroventricular administration of NPY (2 µg/2 µl, 4 days after TMT-treatment), which plays an adjuvant role in neurodegeneration and epilepsy. Our results indicate that 30 days after NPY administration the number of new neurons was still higher in TMT+NPY-treated rats than in control+saline group. As a functional correlate of the integration of new neurons into the hippocampal network, long-term potentiation recorded in Dentate Gyrus (DG) in the absence of GABAA receptor blockade was higher in the TMT+NPY-treated group than in all other groups. Furthermore, qPCR analysis of Kruppel-like factor 9, a transcription factor essential for late-phase maturation of neurons in the DG, and of the cyclin-dependent kinase 5, critically involved in the maturation and dendrite extension of newly-born neurons, revealed a significant up-regulation of both genes in TMT+NPY-treated rats compared with all other groups. To explore the early molecular events activated by NPY administration, the Sonic Hedgehog (Shh) signalling pathway, which participates in the maintenance of the neurogenic hippocampal niche, was evaluated by qPCR 1, 3 and 5 days after NPY-treatment. An early significant up-regulation of Shh expression was detected in TMT+NPY-treated rats compared with all other groups, associated with a modulation of downstream genes. Our data indicate that the neurogenic effect of NPY administration during TMT-induced neurodegeneration involves early Shh pathway activation and results in a functional integration of newly-generated neurons into the local circuit.
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Affiliation(s)
- Valentina Corvino
- Institute of Anatomy and Cell Biology - Università Cattolica del Sacro Cuore, Rome, Italy
| | - Elisa Marchese
- Institute of Anatomy and Cell Biology - Università Cattolica del Sacro Cuore, Rome, Italy
| | - Maria Vittoria Podda
- Institute of Human Physiology - Università Cattolica del Sacro Cuore, Rome, Italy
| | - Wanda Lattanzi
- Institute of Anatomy and Cell Biology - Università Cattolica del Sacro Cuore, Rome, Italy
| | - Stefano Giannetti
- Institute of Anatomy and Cell Biology - Università Cattolica del Sacro Cuore, Rome, Italy
| | - Valentina Di Maria
- Institute of Anatomy and Cell Biology - Università Cattolica del Sacro Cuore, Rome, Italy
| | - Sara Cocco
- Institute of Human Physiology - Università Cattolica del Sacro Cuore, Rome, Italy
| | - Claudio Grassi
- Institute of Human Physiology - Università Cattolica del Sacro Cuore, Rome, Italy
| | - Fabrizio Michetti
- Institute of Anatomy and Cell Biology - Università Cattolica del Sacro Cuore, Rome, Italy
| | - Maria Concetta Geloso
- Institute of Anatomy and Cell Biology - Università Cattolica del Sacro Cuore, Rome, Italy
- * E-mail:
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18
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Podda MV, Leone L, Barbati SA, Mastrodonato A, Li Puma DD, Piacentini R, Grassi C. Extremely low-frequency electromagnetic fields enhance the survival of newborn neurons in the mouse hippocampus. Eur J Neurosci 2013; 39:893-903. [DOI: 10.1111/ejn.12465] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2013] [Revised: 11/26/2013] [Accepted: 11/28/2013] [Indexed: 01/12/2023]
Affiliation(s)
- Maria V. Podda
- Institute of Human Physiology; Medical School; Università Cattolica del Sacro Cuore; Largo Francesco Vito 1 00168 Rome Italy
| | - Lucia Leone
- Institute of Human Physiology; Medical School; Università Cattolica del Sacro Cuore; Largo Francesco Vito 1 00168 Rome Italy
| | - Saviana A. Barbati
- Institute of Human Physiology; Medical School; Università Cattolica del Sacro Cuore; Largo Francesco Vito 1 00168 Rome Italy
| | - Alessia Mastrodonato
- Institute of Human Physiology; Medical School; Università Cattolica del Sacro Cuore; Largo Francesco Vito 1 00168 Rome Italy
| | - Domenica D. Li Puma
- Institute of Human Physiology; Medical School; Università Cattolica del Sacro Cuore; Largo Francesco Vito 1 00168 Rome Italy
| | - Roberto Piacentini
- Institute of Human Physiology; Medical School; Università Cattolica del Sacro Cuore; Largo Francesco Vito 1 00168 Rome Italy
| | - Claudio Grassi
- Institute of Human Physiology; Medical School; Università Cattolica del Sacro Cuore; Largo Francesco Vito 1 00168 Rome Italy
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Podda MV, Grassi C. New perspectives in cyclic nucleotide-mediated functions in the CNS: the emerging role of cyclic nucleotide-gated (CNG) channels. Pflugers Arch 2013; 466:1241-57. [PMID: 24142069 DOI: 10.1007/s00424-013-1373-2] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2013] [Revised: 09/27/2013] [Accepted: 09/28/2013] [Indexed: 01/07/2023]
Abstract
Cyclic nucleotides play fundamental roles in the central nervous system (CNS) under both physiological and pathological conditions. The impact of cAMP and cGMP signaling on neuronal and glial cell functions has been thoroughly characterized. Most of their effects have been related to cyclic nucleotide-dependent protein kinase activity. However, cyclic nucleotide-gated (CNG) channels, first described as key mediators of sensory transduction in retinal and olfactory receptors, have been receiving increasing attention as possible targets of cyclic nucleotides in the CNS. In the last 15 years, consistent evidence has emerged for their expression in neurons and astrocytes of the rodent brain. Far less is known, however, about the functional role of CNG channels in these cells, although several of their features, such as Ca(2+) permeability and prolonged activation in the presence of cyclic nucleotides, make them ideal candidates for mediators of physiological functions in the CNS. Here, we review literature suggesting the involvement of CNG channels in a number of CNS cellular functions (e.g., regulation of membrane potential, neuronal excitability, and neurotransmitter release) as well as in more complex phenomena, like brain plasticity, adult neurogenesis, and pain sensitivity. The emerging picture is that functional and dysfunctional cyclic nucleotide signaling in the CNS has to be reconsidered including CNG channels among possible targets. However, concerted efforts and multidisciplinary approaches are still needed to get more in-depth knowledge in this field.
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Affiliation(s)
- Maria Vittoria Podda
- Institute of Human Physiology, Medical School, Università Cattolica, Largo Francesco Vito 1, 00168, Rome, Italy
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20
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Effect of phosphodiesterase-5 inhibition on apoptosis and beta amyloid load in aged mice. Neurobiol Aging 2013; 35:520-31. [PMID: 24112792 DOI: 10.1016/j.neurobiolaging.2013.09.002] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2013] [Revised: 09/05/2013] [Accepted: 09/06/2013] [Indexed: 01/06/2023]
Abstract
Age-related cognitive decline is accompanied by an increase of neuronal apoptosis and a dysregulation of neuroplasticity-related molecules such as brain-derived neurotrophic factor and neurotoxic factors including beta amyloid (Aβ) peptide. Because it has been previously demonstrated that phosphodiesterase-5 inhibitors (PDE5-Is) protect against hippocampal synaptic dysfunction and memory deficits in mouse models of Alzheimer's disease and physiological aging, we investigated the effect of a treatment with the PDE5-I, sildenafil, on cell death, pro- and antiapoptotic molecules, and Aβ production. We demonstrated that chronic intraperitoneal injection of sildenafil (3 mg/kg for 3 weeks) decreased terminal deoxyuridine triphosphate nick end labeling-positive cells in the CA1 hippocampal area of 26-30-month-old mice, downregulating the proapoptotic proteins, caspase-3 and B-cell lymphoma 2-associated X, and increasing antiapoptotic molecules such as B-cell lymphoma protein-2 and brain-derived neurotrophic factor. Also, sildenafil reverted the shifting of amyloid precursor protein processing toward Aβ42 production and the increase of the Aβ42:Aβ40 ratio in aged mice. Our data suggest that PDE5-I might be beneficial to treat age-related detrimental features in a physiological mouse model of aging.
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Puzzo D, Bizzoca A, Privitera L, Furnari D, Giunta S, Girolamo F, Pinto M, Gennarini G, Palmeri A. F3/Contactin promotes hippocampal neurogenesis, synaptic plasticity, and memory in adult mice. Hippocampus 2013; 23:1367-82. [PMID: 23939883 DOI: 10.1002/hipo.22186] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2013] [Revised: 07/23/2013] [Accepted: 08/02/2013] [Indexed: 12/18/2022]
Abstract
F3/contactin, a cell-adhesion molecule belonging to the immunoglobulin supergene family, is involved in several aspects of neural development including synapse building, maintenance and functioning. Here, we examine F3/contactin function in adult hippocampal neurogenesis, synaptic plasticity, and memory, using as a model TAG/F3 transgenic mice, where F3/contactin overexpression was induced under control of regulatory sequences from the human TAG-1 (TAX-1) gene. Transgenic mice aged 5 (M5) and 12 (M12) months exhibited an increase in hippocampal size, which correlated with positive effects on precursor proliferation and NeuN expression, these data suggesting a possible role for F3/contactin in promoting adult hippocampal neurogenesis. On the functional level, TAG/F3 mice exhibited increased CA1 long-term potentiation and improved spatial and object recognition memory, notably at 12 months of age. Interestingly, these mice showed an increased expression of the phosphorylated transcription factor CREB, which may represent the main molecular correlate of the observed morphological and functional effects. Altogether, these findings indicate for the first time that F3/contactin plays a role in promoting adult hippocampal neurogenesis and that this effect correlates with improved synaptic function and memory.
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Affiliation(s)
- Daniela Puzzo
- Section of Physiology, Department of Bio-Medical Sciences, University of Catania, Catania, Italy
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22
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Podda MV, Piacentini R, Barbati SA, Mastrodonato A, Puzzo D, D’Ascenzo M, Leone L, Grassi C. Role of cyclic nucleotide-gated channels in the modulation of mouse hippocampal neurogenesis. PLoS One 2013; 8:e73246. [PMID: 23991183 PMCID: PMC3750014 DOI: 10.1371/journal.pone.0073246] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2013] [Accepted: 07/18/2013] [Indexed: 12/25/2022] Open
Abstract
Neural stem cells generate neurons in the hippocampal dentate gyrus in mammals, including humans, throughout adulthood. Adult hippocampal neurogenesis has been the focus of many studies due to its relevance in processes such as learning and memory and its documented impairment in some neurodegenerative diseases. However, we are still far from having a complete picture of the mechanism regulating this process. Our study focused on the possible role of cyclic nucleotide-gated (CNG) channels. These voltage-independent channels activated by cyclic nucleotides, first described in retinal and olfactory receptors, have been receiving increasing attention for their involvement in several brain functions. Here we show that the rod-type, CNGA1, and olfactory-type, CNGA2, subunits are expressed in hippocampal neural stem cells in culture and in situ in the hippocampal neurogenic niche of adult mice. Pharmacological blockade of CNG channels did not affect cultured neural stem cell proliferation but reduced their differentiation towards the neuronal phenotype. The membrane permeant cGMP analogue, 8-Br-cGMP, enhanced neural stem cell differentiation to neurons and this effect was prevented by CNG channel blockade. In addition, patch-clamp recording from neuron-like differentiating neural stem cells revealed cGMP-activated currents attributable to ion flow through CNG channels. The current work provides novel insights into the role of CNG channels in promoting hippocampal neurogenesis, which may prove to be relevant for stem cell-based treatment of cognitive impairment and brain damage.
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Affiliation(s)
- Maria Vittoria Podda
- Institute of Human Physiology, Medical School, Università Cattolica, Rome, Italy
| | - Roberto Piacentini
- Institute of Human Physiology, Medical School, Università Cattolica, Rome, Italy
| | | | - Alessia Mastrodonato
- Institute of Human Physiology, Medical School, Università Cattolica, Rome, Italy
| | - Daniela Puzzo
- Section of Physiology, Department of Bio-Medical Sciences, University of Catania, Catania, Italy
| | - Marcello D’Ascenzo
- Institute of Human Physiology, Medical School, Università Cattolica, Rome, Italy
| | - Lucia Leone
- Institute of Human Physiology, Medical School, Università Cattolica, Rome, Italy
| | - Claudio Grassi
- Institute of Human Physiology, Medical School, Università Cattolica, Rome, Italy
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