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Takács V, Bardóczi Z, Orosz Á, Major A, Tar L, Berki P, Papp P, Mayer MI, Sebők H, Zsolt L, Sos KE, Káli S, Freund TF, Nyiri G. Synaptic and dendritic architecture of different types of hippocampal somatostatin interneurons. PLoS Biol 2024; 22:e3002539. [PMID: 38470935 PMCID: PMC10959371 DOI: 10.1371/journal.pbio.3002539] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2023] [Revised: 03/22/2024] [Accepted: 02/06/2024] [Indexed: 03/14/2024] Open
Abstract
GABAergic inhibitory neurons fundamentally shape the activity and plasticity of cortical circuits. A major subset of these neurons contains somatostatin (SOM); these cells play crucial roles in neuroplasticity, learning, and memory in many brain areas including the hippocampus, and are implicated in several neuropsychiatric diseases and neurodegenerative disorders. Two main types of SOM-containing cells in area CA1 of the hippocampus are oriens-lacunosum-moleculare (OLM) cells and hippocampo-septal (HS) cells. These cell types show many similarities in their soma-dendritic architecture, but they have different axonal targets, display different activity patterns in vivo, and are thought to have distinct network functions. However, a complete understanding of the functional roles of these interneurons requires a precise description of their intrinsic computational properties and their synaptic interactions. In the current study we generated, analyzed, and make available several key data sets that enable a quantitative comparison of various anatomical and physiological properties of OLM and HS cells in mouse. The data set includes detailed scanning electron microscopy (SEM)-based 3D reconstructions of OLM and HS cells along with their excitatory and inhibitory synaptic inputs. Combining this core data set with other anatomical data, patch-clamp electrophysiology, and compartmental modeling, we examined the precise morphological structure, inputs, outputs, and basic physiological properties of these cells. Our results highlight key differences between OLM and HS cells, particularly regarding the density and distribution of their synaptic inputs and mitochondria. For example, we estimated that an OLM cell receives about 8,400, whereas an HS cell about 15,600 synaptic inputs, about 16% of which are GABAergic. Our data and models provide insight into the possible basis of the different functionality of OLM and HS cell types and supply essential information for more detailed functional models of these neurons and the hippocampal network.
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Affiliation(s)
- Virág Takács
- Laboratory of Cerebral Cortex Research, HUN-REN Institute of Experimental Medicine, Budapest, Hungary
| | - Zsuzsanna Bardóczi
- Laboratory of Cerebral Cortex Research, HUN-REN Institute of Experimental Medicine, Budapest, Hungary
| | - Áron Orosz
- Laboratory of Cerebral Cortex Research, HUN-REN Institute of Experimental Medicine, Budapest, Hungary
- János Szentágothai Doctoral School of Neurosciences, Semmelweis University, Budapest, Hungary
| | - Abel Major
- Laboratory of Cerebral Cortex Research, HUN-REN Institute of Experimental Medicine, Budapest, Hungary
| | - Luca Tar
- Laboratory of Cerebral Cortex Research, HUN-REN Institute of Experimental Medicine, Budapest, Hungary
- Roska Tamás Doctoral School of Sciences and Technology, Pázmány Péter Catholic University, Budapest, Hungary
| | - Péter Berki
- Laboratory of Cerebral Cortex Research, HUN-REN Institute of Experimental Medicine, Budapest, Hungary
- János Szentágothai Doctoral School of Neurosciences, Semmelweis University, Budapest, Hungary
| | - Péter Papp
- Laboratory of Cerebral Cortex Research, HUN-REN Institute of Experimental Medicine, Budapest, Hungary
| | - Márton I. Mayer
- Laboratory of Cerebral Cortex Research, HUN-REN Institute of Experimental Medicine, Budapest, Hungary
- János Szentágothai Doctoral School of Neurosciences, Semmelweis University, Budapest, Hungary
| | - Hunor Sebők
- Laboratory of Cerebral Cortex Research, HUN-REN Institute of Experimental Medicine, Budapest, Hungary
| | - Luca Zsolt
- Laboratory of Cerebral Cortex Research, HUN-REN Institute of Experimental Medicine, Budapest, Hungary
| | - Katalin E. Sos
- Laboratory of Cerebral Cortex Research, HUN-REN Institute of Experimental Medicine, Budapest, Hungary
- János Szentágothai Doctoral School of Neurosciences, Semmelweis University, Budapest, Hungary
| | - Szabolcs Káli
- Laboratory of Cerebral Cortex Research, HUN-REN Institute of Experimental Medicine, Budapest, Hungary
| | - Tamás F. Freund
- Laboratory of Cerebral Cortex Research, HUN-REN Institute of Experimental Medicine, Budapest, Hungary
| | - Gábor Nyiri
- Laboratory of Cerebral Cortex Research, HUN-REN Institute of Experimental Medicine, Budapest, Hungary
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Guet-McCreight A, Chameh HM, Mazza F, Prevot TD, Valiante TA, Sibille E, Hay E. In-silico testing of new pharmacology for restoring inhibition and human cortical function in depression. Commun Biol 2024; 7:225. [PMID: 38396202 PMCID: PMC10891083 DOI: 10.1038/s42003-024-05907-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Accepted: 02/09/2024] [Indexed: 02/25/2024] Open
Abstract
Reduced inhibition by somatostatin-expressing interneurons is associated with depression. Administration of positive allosteric modulators of α5 subunit-containing GABAA receptor (α5-PAM) that selectively target this lost inhibition exhibit antidepressant and pro-cognitive effects in rodent models of chronic stress. However, the functional effects of α5-PAM on the human brain in vivo are unknown, and currently cannot be assessed experimentally. We modeled the effects of α5-PAM on tonic inhibition as measured in human neurons, and tested in silico α5-PAM effects on detailed models of human cortical microcircuits in health and depression. We found that α5-PAM effectively recovered impaired cortical processing as quantified by stimulus detection metrics, and also recovered the power spectral density profile of the microcircuit EEG signals. We performed an α5-PAM dose-response and identified simulated EEG biomarker candidates. Our results serve to de-risk and facilitate α5-PAM translation and provide biomarkers in non-invasive brain signals for monitoring target engagement and drug efficacy.
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Affiliation(s)
- Alexandre Guet-McCreight
- Krembil Centre for Neuroinformatics, Centre for Addiction and Mental Health, Toronto, ON, Canada.
| | | | - Frank Mazza
- Krembil Centre for Neuroinformatics, Centre for Addiction and Mental Health, Toronto, ON, Canada
- Department of Physiology, University of Toronto, Toronto, ON, Canada
| | - Thomas D Prevot
- Department of Psychiatry, University of Toronto, Toronto, ON, Canada
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada
| | - Taufik A Valiante
- Krembil Brain Institute, University Health Network, Toronto, ON, Canada
- Institute of Medical Sciences, University of Toronto, Toronto, ON, Canada
- Department of Electrical and Computer Engineering, University of Toronto, Toronto, ON, Canada
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, ON, Canada
- Department of Surgery, University of Toronto, Toronto, ON, Canada
- Center for Advancing Neurotechnological Innovation to Application, Toronto, ON, Canada
- Max Planck-University of Toronto Center for Neural Science and Technology, Toronto, ON, Canada
| | - Etienne Sibille
- Department of Psychiatry, University of Toronto, Toronto, ON, Canada
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada
- Department of Pharmacology and Toxicology, University of Toronto, Toronto, ON, Canada
| | - Etay Hay
- Krembil Centre for Neuroinformatics, Centre for Addiction and Mental Health, Toronto, ON, Canada.
- Department of Physiology, University of Toronto, Toronto, ON, Canada.
- Department of Psychiatry, University of Toronto, Toronto, ON, Canada.
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Milewska-Kranc A, Ćwikła JB, Kolasinska-Ćwikła A. The Role of Receptor-Ligand Interaction in Somatostatin Signaling Pathways: Implications for Neuroendocrine Tumors. Cancers (Basel) 2023; 16:116. [PMID: 38201544 PMCID: PMC10778465 DOI: 10.3390/cancers16010116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Revised: 12/19/2023] [Accepted: 12/22/2023] [Indexed: 01/12/2024] Open
Abstract
Neuroendocrine tumors (NETs) arise from neuroendocrine cells and manifest in diverse organs. Key players in their regulation are somatostatin and its receptors (SSTR1-SSTR5). Understanding receptor-ligand interactions and signaling pathways is vital for elucidating their role in tumor development and therapeutic potential. This review highlights SSTR characteristics, localization, and expression in tissues, impacting physiological functions. Mechanisms of somatostatin and synthetic analogue binding to SSTRs, their selectivity, and their affinity were analyzed. Upon activation, somatostatin initiates intricate intracellular signaling, involving cAMP, PLC, and MAP kinases and influencing growth, differentiation, survival, and hormone secretion in NETs. This review explores SSTR expression in different tumor types, examining receptor activation effects on cancer cells. SSTRs' significance as therapeutic targets is discussed. Additionally, somatostatin and analogues' role in hormone secretion regulation, tumor growth, and survival is emphasized, presenting relevant therapeutic examples. In conclusion, this review advances the knowledge of receptor-ligand interactions and signaling pathways in somatostatin receptors, with potential for improved neuroendocrine tumor treatments.
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Affiliation(s)
| | - Jarosław B. Ćwikła
- School of Medicine, University of Warmia and Mazury, Aleja Warszawska 30, 10-082 Olsztyn, Poland
- Diagnostic Therapeutic Center–Gammed, Lelechowska 5, 02-351 Warsaw, Poland
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Liwinski T, Lang UE, Brühl AB, Schneider E. Exploring the Therapeutic Potential of Gamma-Aminobutyric Acid in Stress and Depressive Disorders through the Gut-Brain Axis. Biomedicines 2023; 11:3128. [PMID: 38137351 PMCID: PMC10741010 DOI: 10.3390/biomedicines11123128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Revised: 11/16/2023] [Accepted: 11/21/2023] [Indexed: 12/24/2023] Open
Abstract
Research conducted on individuals with depression reveals that major depressive disorders (MDDs) coincide with diminished levels of the inhibitory neurotransmitter γ-aminobutyric acid (GABA) in the brain, as well as modifications in the subunit composition of the primary receptors (GABAA receptors) responsible for mediating GABAergic inhibition. Furthermore, there is substantial evidence supporting the significant role of GABA in regulating stress within the brain, which is a pivotal vulnerability factor in mood disorders. GABA is readily available and approved as a food supplement in many countries. Although there is substantial evidence indicating that orally ingested GABA may affect GABA receptors in peripheral tissues, there is comparatively less evidence supporting its direct action within the brain. Emerging evidence highlights that oral GABA intake may exert beneficial effects on the brain and psyche through the gut-brain axis. While GABA enjoys wide consumer acceptance in Eastern Asian markets, with many consumers reporting favorable effects on stress regulation, mood, and sleep, rigorous independent research is still largely lacking. Basic research, coupled with initial clinical findings, makes GABA an intriguing neuro-nutritional compound deserving of clinical studies in individuals with depression and other psychological problems.
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Affiliation(s)
| | | | | | - Else Schneider
- University Psychiatric Clinics Basel, Clinic for Adults, University of Basel, CH-4002 Basel, Switzerland; (T.L.); (U.E.L.); (A.B.B.)
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Somatostatin slows Aβ plaque deposition in aged APP NL-F/NL-F mice by blocking Aβ aggregation. Sci Rep 2023; 13:2337. [PMID: 36759538 PMCID: PMC9911728 DOI: 10.1038/s41598-023-29559-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Accepted: 02/06/2023] [Indexed: 02/11/2023] Open
Abstract
The neuroendocrine peptide somatostatin (SST) has long been thought of as influencing the deposition of the amyloid β peptide (Aβ) in Alzheimer's disease (AD). Missing have been in vivo data in a relevant Aβ amyloidosis model. Here we crossed AppNL-F/NL-F mice with Sst-deficient mice to assess if and how the presence of Sst influences pathological hallmarks of Aβ amyloidosis. We found that Sst had no influence on whole brain neprilysin transcript, protein or activity levels, an observation that cannot be accounted for by a compensatory upregulation of the Sst paralog, cortistatin (Cort), that we observed in 15-month-old Sst-deficient mice. Sst-deficiency led to a subtle but significant increase in the density of cortical Aβ amyloid plaques. Follow-on western blot analyses of whole brain extracts indicated that Sst interferes with early steps of Aβ assembly that manifest in the appearance of SDS-stable smears of 55-150 kDa in Sst null brain samples. As expected, no effect of Sst on tau steady-state levels or its phosphorylation were observed. Results from this study are easier reconciled with an emerging body of data that point toward Sst affecting Aβ amyloid plaque formation through direct interference with Aβ aggregation rather than through its effects on neprilysin expression.
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Uzunhisarcıklı E, Yerer MB. Neuroprotective Effects of Vapreotide on Tau Transfection-Induced Neurodegeneration. Neurotox Res 2022; 40:1824-1837. [PMID: 36378411 DOI: 10.1007/s12640-022-00588-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Revised: 09/22/2022] [Accepted: 10/08/2022] [Indexed: 11/16/2022]
Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative disease characterized by loss of neurons and synapses. The aim of this study was to investigate the effect of somatostatin analogue Vapreotide in an in vitro Alzheimer's model and its effects based on the relationship between somatostatinergic transmission and neurodegenerative functions. In this study, tau transfection was performed using the MAPT gene cloned into the pcDNA3.1 vector and transfection reagent into the SH-SY5Y cell line. In viability experiments using 10 µM Memantine as a positive control, it was observed that Vapreotide at 50 µM (p < 0.0001) and 100 µM (p < 0.05) had a protective effect on cell viability, 100 µM CYN154806 was found to decrease (p < 0.05) cell viability. It was determined that Vapreotide, decreased the expression levels (50 µM-p < 0.001; 100 µM-p < 0.001; 200 µM-p < 0.0001) and phosphorylation of Tau and p-Tau proteins by western blots. With the qRT-PCR method, it was found that Vapreotide, decreased the BAX/BCL2 (50 µM-p < 0.001; 100 µM-p < 0.01; 200 µM-p < 0.001) expression level and decreased the expression level (50 µM-p < 0.01; 100 µM-p < 0.01; 200 µM-p < 0.001) of the APOE4 gene, which constitutes a genetic risk for AD. This study demonstrates a potential therapeutic role for a somatostatin analogue Vapreotide in Alzheimer's disease.
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Affiliation(s)
- Ebru Uzunhisarcıklı
- Faculty of Pharmacy, Department of Pharmacology, Erciyes University, Kayseri, Turkey.
| | - Mükerrem Betül Yerer
- Faculty of Pharmacy, Department of Pharmacology, Erciyes University, Kayseri, Turkey
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Balog M, Anderson A, Gurumurthy CB, Quadros RM, Korade Z, Mirnics K. Knock-in mouse models for studying somatostatin and cholecystokinin expressing cells. J Neurosci Methods 2022; 381:109704. [PMID: 36070817 DOI: 10.1016/j.jneumeth.2022.109704] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Revised: 08/29/2022] [Accepted: 09/01/2022] [Indexed: 12/14/2022]
Abstract
BACKGROUND Somatostatin (SST) and cholecystokinin (CCK) are peptide hormones that regulate the endocrine system, cell proliferation and neurotransmission. NEW METHOD We utilized the novel Easi-CRISPR system to generate two knock-in mouse strains with Cre recombinase in SST- and CCK-expressing cells and validated their utility in the developing and adult brain tissues. RESULTS The full nomenclature for the newly generated strains are C57BL/6-Sstem1(P2A-iCre-T2A-mCherry)Mirn and C57BL/6-Cckem1(iCre-T2A-mCherry-P2A)Mirn. For the Sst locus, a P2A-iCre-T2A-mCherry cassette was inserted immediately upstream of the stop codon (C terminus fusion). For the Cck locus, iCre-P2A-mCherry-T2A cassette was inserted at the start codon (N terminus fusion). Knock-in mice were generated using the Easi-CRISPR method. Developmental and adult SST and CCK expressions were preserved and showed an appropriate expression pattern in both models, with an active fluorescent tag in both animal lines. COMPARISON WITH EXISTING METHODS Knock-in mouse models to study cell types that produce these critically important molecules are limited to date. The knock-in mice we generated can be used as reporters to study development, physiology, or pathophysiology of SST and CCK expressing cells - without interference with native expression of SST and CCK. In addition, they can be used as Cre driver models to conditionally delete floxed genes in SST and CCK expressing cells across various tissues. CONCLUSIONS These two mouse models serve as valuable tools for in vitro and in vivo research studies related to SST and CCK biology across the lifespan and across different tissue types.
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Affiliation(s)
- Marta Balog
- Munroe-Meyer Institute for Genetics and Rehabilitation, University of Nebraska Medical Center Omaha, NE, USA; Department of Medical Biology and Genetics, Faculty of Medicine, University of Osijek, Osijek, Croatia
| | - Allison Anderson
- Munroe-Meyer Institute for Genetics and Rehabilitation, University of Nebraska Medical Center Omaha, NE, USA
| | - Channabasavaiah B Gurumurthy
- Mouse Genome Engineering Core Facility, University of Nebraska Medical Center, Omaha, NE, USA; Department of Pharmacology and Experimental Neuroscience, College of Medicine, University of Nebraska Medical Center, Omaha, NE, USA
| | - Rolen M Quadros
- Mouse Genome Engineering Core Facility, University of Nebraska Medical Center, Omaha, NE, USA
| | - Zeljka Korade
- Department of Pediatrics, University of Nebraska Medical Center Omaha, NE, USA; Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center Omaha, NE, USA; Child Health Research Institute, University of Nebraska Medical Center Omaha, NE, USA.
| | - Karoly Mirnics
- Munroe-Meyer Institute for Genetics and Rehabilitation, University of Nebraska Medical Center Omaha, NE, USA; Department of Pharmacology and Experimental Neuroscience, College of Medicine, University of Nebraska Medical Center, Omaha, NE, USA; Department of Pediatrics, University of Nebraska Medical Center Omaha, NE, USA; Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center Omaha, NE, USA; Child Health Research Institute, University of Nebraska Medical Center Omaha, NE, USA.
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Casello SM, Flores RJ, Yarur HE, Wang H, Awanyai M, Arenivar MA, Jaime-Lara RB, Bravo-Rivera H, Tejeda HA. Neuropeptide System Regulation of Prefrontal Cortex Circuitry: Implications for Neuropsychiatric Disorders. Front Neural Circuits 2022; 16:796443. [PMID: 35800635 PMCID: PMC9255232 DOI: 10.3389/fncir.2022.796443] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2021] [Accepted: 04/27/2022] [Indexed: 01/08/2023] Open
Abstract
Neuropeptides, a diverse class of signaling molecules in the nervous system, modulate various biological effects including membrane excitability, synaptic transmission and synaptogenesis, gene expression, and glial cell architecture and function. To date, most of what is known about neuropeptide action is limited to subcortical brain structures and tissue outside of the central nervous system. Thus, there is a knowledge gap in our understanding of neuropeptide function within cortical circuits. In this review, we provide a comprehensive overview of various families of neuropeptides and their cognate receptors that are expressed in the prefrontal cortex (PFC). Specifically, we highlight dynorphin, enkephalin, corticotropin-releasing factor, cholecystokinin, somatostatin, neuropeptide Y, and vasoactive intestinal peptide. Further, we review the implication of neuropeptide signaling in prefrontal cortical circuit function and use as potential therapeutic targets. Together, this review summarizes established knowledge and highlights unknowns of neuropeptide modulation of neural function underlying various biological effects while offering insights for future research. An increased emphasis in this area of study is necessary to elucidate basic principles of the diverse signaling molecules used in cortical circuits beyond fast excitatory and inhibitory transmitters as well as consider components of neuropeptide action in the PFC as a potential therapeutic target for neurological disorders. Therefore, this review not only sheds light on the importance of cortical neuropeptide studies, but also provides a comprehensive overview of neuropeptide action in the PFC to serve as a roadmap for future studies in this field.
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Affiliation(s)
- Sanne M. Casello
- Unit on Neuromodulation and Synaptic Integration, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, United States
| | - Rodolfo J. Flores
- Unit on Neuromodulation and Synaptic Integration, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, United States
| | - Hector E. Yarur
- Unit on Neuromodulation and Synaptic Integration, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, United States
| | - Huikun Wang
- Unit on Neuromodulation and Synaptic Integration, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, United States
| | - Monique Awanyai
- Unit on Neuromodulation and Synaptic Integration, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, United States
| | - Miguel A. Arenivar
- Unit on Neuromodulation and Synaptic Integration, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, United States
| | - Rosario B. Jaime-Lara
- Unit on Neuromodulation and Synaptic Integration, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, United States
- National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, United States
| | - Hector Bravo-Rivera
- Unit on Neuromodulation and Synaptic Integration, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, United States
| | - Hugo A. Tejeda
- Unit on Neuromodulation and Synaptic Integration, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, United States
- *Correspondence: Hugo A. Tejeda,
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Roles of Neuropeptides in Sleep-Wake Regulation. Int J Mol Sci 2022; 23:ijms23094599. [PMID: 35562990 PMCID: PMC9103574 DOI: 10.3390/ijms23094599] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2022] [Revised: 03/31/2022] [Accepted: 04/19/2022] [Indexed: 12/04/2022] Open
Abstract
Sleep and wakefulness are basic behavioral states that require coordination between several brain regions, and they involve multiple neurochemical systems, including neuropeptides. Neuropeptides are a group of peptides produced by neurons and neuroendocrine cells of the central nervous system. Like traditional neurotransmitters, neuropeptides can bind to specific surface receptors and subsequently regulate neuronal activities. For example, orexin is a crucial component for the maintenance of wakefulness and the suppression of rapid eye movement (REM) sleep. In addition to orexin, melanin-concentrating hormone, and galanin may promote REM sleep. These results suggest that neuropeptides play an important role in sleep–wake regulation. These neuropeptides can be divided into three categories according to their effects on sleep–wake behaviors in rodents and humans. (i) Galanin, melanin-concentrating hormone, and vasoactive intestinal polypeptide are sleep-promoting peptides. It is also noticeable that vasoactive intestinal polypeptide particularly increases REM sleep. (ii) Orexin and neuropeptide S have been shown to induce wakefulness. (iii) Neuropeptide Y and substance P may have a bidirectional function as they can produce both arousal and sleep-inducing effects. This review will introduce the distribution of various neuropeptides in the brain and summarize the roles of different neuropeptides in sleep–wake regulation. We aim to lay the foundation for future studies to uncover the mechanisms that underlie the initiation, maintenance, and end of sleep–wake states.
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Tomoda T, Sumitomo A, Newton D, Sibille E. Molecular origin of somatostatin-positive neuron vulnerability. Mol Psychiatry 2022; 27:2304-2314. [PMID: 35145229 PMCID: PMC9133093 DOI: 10.1038/s41380-022-01463-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 01/11/2022] [Accepted: 01/26/2022] [Indexed: 01/27/2023]
Abstract
Reduced somatostatin (SST) and dysfunction of SST-positive (SST+) neurons are hallmarks of neurological disorders and associated with mood disturbances, but the molecular origin of SST+ neuron vulnerability is unknown. Using chronic psychosocial stress as a paradigm to induce elevated behavioral emotionality in rodents, we report a selective vulnerability of SST+ neurons through exacerbated unfolded protein response (UPR) of the endoplasmic reticulum (ER), or ER stress, in the prefrontal cortex. We next show that genetically suppressing ER stress in SST+ neurons, but not in pyramidal neurons, normalized behavioral emotionality induced by psychosocial stress. In search for intrinsic factors mediating SST+ neuron vulnerability, we found that the forced expression of the SST precursor protein (preproSST) in SST+ neurons, mimicking psychosocial stress-induced early proteomic changes, induces ER stress, whereas mature SST or processing-incompetent preproSST does not. Biochemical analyses further show that psychosocial stress induces SST protein aggregation under elevated ER stress conditions. These results demonstrate that SST processing in the ER is a SST+ neuron-intrinsic vulnerability factor under conditions of sustained or over-activated UPR, hence negatively impacting SST+ neuron functions. Combined with observations in major medical illness, such as diabetes, where excess ER processing of preproinsulin similarly causes ER stress and β cell dysfunction, this suggests a universal mechanism for proteinopathy that is induced by excess processing of native endogenous proteins, playing critical pathophysiological roles that extend to neuropsychiatric disorders.
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Affiliation(s)
- Toshifumi Tomoda
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health (CAMH), Toronto, Ontario, M5T 1R8, Canada.
| | - Akiko Sumitomo
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health (CAMH), Toronto, Ontario, M5T 1R8, Canada
| | - Dwight Newton
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health (CAMH), Toronto, Ontario, M5T 1R8, Canada
| | - Etienne Sibille
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health (CAMH), Toronto, Ontario, M5T 1R8, Canada.
- Department of Psychiatry, University of Toronto, Toronto, Ontario, M5T 1R8, Canada.
- Department of Pharmacology and Toxicology, University of Toronto, Toronto, Ontario, M5T 1R8, Canada.
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Yao HK, Guet-McCreight A, Mazza F, Moradi Chameh H, Prevot TD, Griffiths JD, Tripathy SJ, Valiante TA, Sibille E, Hay E. Reduced inhibition in depression impairs stimulus processing in human cortical microcircuits. Cell Rep 2022; 38:110232. [PMID: 35021088 DOI: 10.1016/j.celrep.2021.110232] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Revised: 10/07/2021] [Accepted: 12/16/2021] [Indexed: 12/01/2022] Open
Abstract
Cortical processing depends on finely tuned excitatory and inhibitory connections in neuronal microcircuits. Reduced inhibition by somatostatin-expressing interneurons is a key component of altered inhibition associated with treatment-resistant major depressive disorder (depression), which is implicated in cognitive deficits and rumination, but the link remains to be better established mechanistically in humans. Here we test the effect of reduced somatostatin interneuron-mediated inhibition on cortical processing in human neuronal microcircuits using a data-driven computational approach. We integrate human cellular, circuit, and gene expression data to generate detailed models of human cortical microcircuits in health and depression. We simulate microcircuit baseline and response activity and find a reduced signal-to-noise ratio and increased false/failed detection of stimuli due to a higher baseline activity in depression. We thus apply models of human cortical microcircuits to demonstrate mechanistically how reduced inhibition impairs cortical processing in depression, providing quantitative links between altered inhibition and cognitive deficits.
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Affiliation(s)
- Heng Kang Yao
- Krembil Centre for Neuroinformatics, Centre for Addiction and Mental Health, Toronto, ON M5T 1R7, Canada; Department of Physiology, University of Toronto, Toronto, ON M5S 1A1, Canada
| | - Alexandre Guet-McCreight
- Krembil Centre for Neuroinformatics, Centre for Addiction and Mental Health, Toronto, ON M5T 1R7, Canada
| | - Frank Mazza
- Krembil Centre for Neuroinformatics, Centre for Addiction and Mental Health, Toronto, ON M5T 1R7, Canada; Department of Physiology, University of Toronto, Toronto, ON M5S 1A1, Canada
| | | | - Thomas D Prevot
- Department of Psychiatry, University of Toronto, Toronto, ON M5S 1A1, Canada; Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON M5T 1R7, Canada
| | - John D Griffiths
- Krembil Centre for Neuroinformatics, Centre for Addiction and Mental Health, Toronto, ON M5T 1R7, Canada; Department of Psychiatry, University of Toronto, Toronto, ON M5S 1A1, Canada; Institute of Medical Sciences, University of Toronto, Toronto, ON M5S 1A1, Canada
| | - Shreejoy J Tripathy
- Krembil Centre for Neuroinformatics, Centre for Addiction and Mental Health, Toronto, ON M5T 1R7, Canada; Department of Physiology, University of Toronto, Toronto, ON M5S 1A1, Canada; Department of Psychiatry, University of Toronto, Toronto, ON M5S 1A1, Canada; Institute of Medical Sciences, University of Toronto, Toronto, ON M5S 1A1, Canada
| | - Taufik A Valiante
- Krembil Research Institute, University Health Network, Toronto, ON M5T 0S8, Canada; Institute of Medical Sciences, University of Toronto, Toronto, ON M5S 1A1, Canada; Department of Electrical and Computer Engineering, University of Toronto, Toronto, ON M5S 1A1; Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, ON M5S 1A1, Canada; Department of Surgery, University of Toronto, Toronto, ON M5S 1A1, Canada; Max Planck-University of Toronto Center for Neural Science and Technology, University of Toronto, Toronto, ON M5S 1A1, Canada; Center for Advancing Neurotechnological Innovation to Application, University of Toronto, Toronto, ON M5S 1A1, Canada
| | - Etienne Sibille
- Department of Psychiatry, University of Toronto, Toronto, ON M5S 1A1, Canada; Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON M5T 1R7, Canada; Department of Pharmacology & Toxicology, University of Toronto, Toronto, ON M5S 1A1, Canada
| | - Etay Hay
- Krembil Centre for Neuroinformatics, Centre for Addiction and Mental Health, Toronto, ON M5T 1R7, Canada; Department of Physiology, University of Toronto, Toronto, ON M5S 1A1, Canada; Department of Psychiatry, University of Toronto, Toronto, ON M5S 1A1, Canada.
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12
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Racine AS, Michon FX, Laplante I, Lacaille JC. Somatostatin contributes to long-term potentiation at excitatory synapses onto hippocampal somatostatinergic interneurons. Mol Brain 2021; 14:130. [PMID: 34429141 PMCID: PMC8385910 DOI: 10.1186/s13041-021-00830-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Accepted: 07/13/2021] [Indexed: 04/13/2023] Open
Abstract
Somatostatin-expressing interneurons (SOM-INs) are a major subpopulation of GABAergic cells in CA1 hippocampus that receive excitation from pyramidal cells (PCs), and, in turn, provide feedback inhibition onto PC dendrites. Excitatory synapses onto SOM-INs show a Hebbian long-term potentiation (LTP) mediated by type 1a metabotropic glutamate receptors (mGluR1a) that is implicated in hippocampus-dependent learning. The neuropeptide somatostatin (SST) is also critical for hippocampal long-term synaptic plasticity, as well as learning and memory. SST effects on hippocampal PCs are well documented, but its actions on inhibitory interneurons remain largely undetermined. In the present work, we investigate the involvement of SST in long-term potentiation of CA1 SOM-IN excitatory synapses using pharmacological approaches targeting the somatostatinergic system and whole cell recordings in slices from transgenic mice expressing eYFP in SOM-INs. We report that application of exogenous SST14 induces long-term potentiation of excitatory postsynaptic potentials in SOM-INs via somatostatin type 1–5 receptors (SST1-5Rs) but does not affect synapses of PC or parvalbumin-expressing interneurons. Hebbian LTP in SOM-INs was prevented by inhibition of SSTRs and by depletion of SST by cysteamine treatment, suggesting a critical role of endogenous SST in LTP. LTP of SOM-IN excitatory synapses induced by SST14 was independent of NMDAR and mGluR1a, activity-dependent, and prevented by blocking GABAA receptor function. Our results indicate that endogenous SST may contribute to Hebbian LTP at excitatory synapses of SOM-INs by controlling GABAA inhibition, uncovering a novel role for SST in regulating long-term synaptic plasticity in somatostatinergic cells that may be important for hippocampus-dependent memory processes.
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Affiliation(s)
- Anne-Sophie Racine
- Centre for Interdisciplinary Research on Brain and Learning, Research Group on the Central Nervous System, Department of Neurosciences, Université de Montréal, P.O. Box 6128, Station Downtown, Montreal, QC, H3C 3J7, Canada
| | - François-Xavier Michon
- Centre for Interdisciplinary Research on Brain and Learning, Research Group on the Central Nervous System, Department of Neurosciences, Université de Montréal, P.O. Box 6128, Station Downtown, Montreal, QC, H3C 3J7, Canada
| | - Isabel Laplante
- Centre for Interdisciplinary Research on Brain and Learning, Research Group on the Central Nervous System, Department of Neurosciences, Université de Montréal, P.O. Box 6128, Station Downtown, Montreal, QC, H3C 3J7, Canada
| | - Jean-Claude Lacaille
- Centre for Interdisciplinary Research on Brain and Learning, Research Group on the Central Nervous System, Department of Neurosciences, Université de Montréal, P.O. Box 6128, Station Downtown, Montreal, QC, H3C 3J7, Canada.
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13
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Neumann WL, Sandoval KE, Mobayen S, Minaeian M, Kukielski SG, Srabony KN, Frare R, Slater O, Farr SA, Niehoff ML, Hospital A, Kontoyianni M, Crider AM, Witt KA. Synthesis and structure-activity relationships of 3,4,5-trisubstituted-1,2,4-triazoles: high affinity and selective somatostatin receptor-4 agonists for Alzheimer's disease treatment. RSC Med Chem 2021; 12:1352-1365. [PMID: 34458738 DOI: 10.1039/d1md00044f] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Accepted: 04/14/2021] [Indexed: 12/23/2022] Open
Abstract
Somatostatin receptor-4 (SST4) is highly expressed in brain regions affiliated with learning and memory. SST4 agonist treatment may act to mitigate Alzheimer's disease (AD) pathology. An integrated approach to SST4 agonist lead optimization is presented herein. High affinity and selective agonists with biological efficacy were identified through iterative cycles of a structure-based design strategy encompassing computational methods, chemistry, and preclinical pharmacology. 1,2,4-Triazole derivatives of our previously reported hit (4) showed enhanced SST4 binding affinity, activity, and selectivity. Thirty-five compounds showed low nanomolar range SST4 binding affinity, 12 having a K i < 1 nM. These compounds showed >500-fold affinity for SST4 as compared to SST2A. SST4 activities were consistent with the respective SST4 binding affinities (EC50 < 10 nM for 34 compounds). Compound 208 (SST4 K i = 0.7 nM; EC50 = 2.5 nM; >600-fold selectivity over SST2A) display a favorable physiochemical profile, and was advanced to learning and memory behavior evaluations in the senescence accelerated mouse-prone 8 model of AD-related cognitive decline. Chronic administration enhanced learning with i.p. dosing (1 mg kg-1) compared to vehicle. Chronic administration enhanced memory with both i.p. (0.01, 0.1, 1 mg kg-1) and oral (0.01, 10 mg kg-1) dosing compared to vehicle. This study identified a novel series of SST4 agonists with high affinity, selectivity, and biological activity that may be useful in the treatment of AD.
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Affiliation(s)
- William L Neumann
- Department of Pharmaceutical Sciences, School of Pharmacy, Southern Illinois University Edwardsville Edwardsville IL 62026 USA
| | - Karin E Sandoval
- Department of Pharmaceutical Sciences, School of Pharmacy, Southern Illinois University Edwardsville Edwardsville IL 62026 USA
| | - Shirin Mobayen
- Department of Pharmaceutical Sciences, School of Pharmacy, Southern Illinois University Edwardsville Edwardsville IL 62026 USA
| | - Mahsa Minaeian
- Department of Pharmaceutical Sciences, School of Pharmacy, Southern Illinois University Edwardsville Edwardsville IL 62026 USA
| | - Stephen G Kukielski
- Department of Pharmaceutical Sciences, School of Pharmacy, Southern Illinois University Edwardsville Edwardsville IL 62026 USA
| | - Khush N Srabony
- Department of Pharmaceutical Sciences, School of Pharmacy, Southern Illinois University Edwardsville Edwardsville IL 62026 USA
| | - Rafael Frare
- Department of Pharmaceutical Sciences, School of Pharmacy, Southern Illinois University Edwardsville Edwardsville IL 62026 USA
| | - Olivia Slater
- Department of Pharmaceutical Sciences, School of Pharmacy, Southern Illinois University Edwardsville Edwardsville IL 62026 USA
| | - Susan A Farr
- Research and Development Service, VA Medical Center, Division of Geriatric Medicine, Saint Louis University School of Medicine 1402 South Grand Boulevard, M238 St Louis MO 63104 USA
| | - Michael L Niehoff
- Research and Development Service, VA Medical Center, Division of Geriatric Medicine, Saint Louis University School of Medicine 1402 South Grand Boulevard, M238 St Louis MO 63104 USA
| | - Audrey Hospital
- Department of Pharmaceutical Sciences, School of Pharmacy, Southern Illinois University Edwardsville Edwardsville IL 62026 USA
| | - Maria Kontoyianni
- Department of Pharmaceutical Sciences, School of Pharmacy, Southern Illinois University Edwardsville Edwardsville IL 62026 USA
| | - A Michael Crider
- Department of Pharmaceutical Sciences, School of Pharmacy, Southern Illinois University Edwardsville Edwardsville IL 62026 USA
| | - Ken A Witt
- Department of Pharmaceutical Sciences, School of Pharmacy, Southern Illinois University Edwardsville Edwardsville IL 62026 USA
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14
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Somatostatin and Astroglial Involvement in the Human Limbic System in Alzheimer's Disease. Int J Mol Sci 2021; 22:ijms22168434. [PMID: 34445147 PMCID: PMC8395127 DOI: 10.3390/ijms22168434] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Revised: 07/28/2021] [Accepted: 08/04/2021] [Indexed: 11/16/2022] Open
Abstract
Alzheimer's disease (AD) is the most prevalent neurodegenerative disease in the elderly. Progressive accumulation of insoluble isoforms of amyloid-β peptide (Aβ) and tau protein are the major neuropathologic hallmarks, and the loss of cholinergic pathways underlies cognitive deficits in patients. Recently, glial involvement has gained interest regarding its effect on preservation and impairment of brain integrity. The limbic system, including temporal lobe regions and the olfactory bulb, is particularly affected in the early stages. In the early 1980s, the reduced expression of the somatostatin neuropeptide was described in AD. However, over the last three decades, research on somatostatin in Alzheimer's disease has been scarce in humans. Therefore, the aim of this study was to stereologically quantify the expression of somatostatin in the human hippocampus and olfactory bulb and analyze its spatial distribution with respect to that of Aβ and au neuropathologic proteins and astroglia. The results indicate that somatostatin-expressing cells are reduced by 50% in the hippocampus but are preserved in the olfactory bulb. Interestingly, the coexpression of somatostatin with the Aβ peptide is very common but not with the tau protein. Finally, the coexpression of somatostatin with astrocytes is rare, although their spatial distribution is very similar. Altogether, we can conclude that somatostatin expression is highly reduced in the human hippocampus, but not the olfactory bulb, and may play a role in Alzheimer's disease pathogenesis.
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15
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Wide-Ranging Effects on the Brain Proteome in a Transgenic Mouse Model of Alzheimer's Disease Following Treatment with a Brain-Targeting Somatostatin Peptide. ACS Chem Neurosci 2021; 12:2529-2541. [PMID: 34170117 PMCID: PMC8291608 DOI: 10.1021/acschemneuro.1c00303] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
![]()
Alzheimer’s
disease is the most common neurodegenerative
disorder characterized by the pathological aggregation of amyloid-β
(Aβ) peptide. A potential therapeutic intervention in Alzheimer’s
disease is to enhance Aβ degradation by increasing the activity
of Aβ-degrading enzymes, including neprilysin. The somatostatin
(SST) peptide has been identified as an activator of neprilysin. Recently,
we demonstrated the ability of a brain-penetrating SST peptide (SST-scFv8D3)
to increase neprilysin activity and membrane-bound Aβ42 degradation
in the hippocampus of mice overexpressing the Aβ-precursor protein
with the Swedish mutation (APPswe). Using LC–MS, we further
evaluated the anti-Alzheimer’s disease effects of SST-scFv8D3.
Following a triple intravenous injection of SST-scFv8D3, the LC–MS
analysis of the brain proteome revealed that the majority of downregulated
proteins consisted of mitochondrial proteins regulating fatty acid
oxidation, which are otherwise upregulated in APPswe mice compared
to wild-type mice. Moreover, treatment with SST-scFv8D3 significantly
increased hippocampal levels of synaptic proteins regulating cell
membrane trafficking and neuronal development. Finally, hippocampal
concentrations of growth-regulated α (KC/GRO) chemokine and
degradation of neuropeptide-Y were elevated after SST-scFv8D3 treatment.
In summary, our results demonstrate a multifaceted effect profile
in regulating mitochondrial function and neurogenesis following treatment
with SST-scFv8D3, further suggesting the development of Alzheimer’s
disease therapies based on SST peptides.
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Tennakoon M, Senarath K, Kankanamge D, Ratnayake K, Wijayaratna D, Olupothage K, Ubeysinghe S, Martins-Cannavino K, Hébert TE, Karunarathne A. Subtype-dependent regulation of Gβγ signalling. Cell Signal 2021; 82:109947. [PMID: 33582184 PMCID: PMC8026654 DOI: 10.1016/j.cellsig.2021.109947] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 02/01/2021] [Accepted: 02/02/2021] [Indexed: 01/04/2023]
Abstract
G protein-coupled receptors (GPCRs) transmit information to the cell interior by transducing external signals to heterotrimeric G protein subunits, Gα and Gβγ subunits, localized on the inner leaflet of the plasma membrane. Though the initial focus was mainly on Gα-mediated events, Gβγ subunits were later identified as major contributors to GPCR-G protein signalling. A broad functional array of Gβγ signalling has recently been attributed to Gβ and Gγ subtype diversity, comprising 5 Gβ and 12 Gγ subtypes, respectively. In addition to displaying selectivity towards each other to form the Gβγ dimer, numerous studies have identified preferences of distinct Gβγ combinations for specific GPCRs, Gα subtypes and effector molecules. Importantly, Gβ and Gγ subtype-dependent regulation of downstream effectors, representing a diverse range of signalling pathways and physiological functions have been found. Here, we review the literature on the repercussions of Gβ and Gγ subtype diversity on direct and indirect regulation of GPCR/G protein signalling events and their physiological outcomes. Our discussion additionally provides perspective in understanding the intricacies underlying molecular regulation of subtype-specific roles of Gβγ signalling and associated diseases.
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Affiliation(s)
- Mithila Tennakoon
- Department of Chemistry and Biochemistry, The University of Toledo, Toledo, OH 43606, USA
| | - Kanishka Senarath
- Genetics and Molecular Biology Unit, University of Sri Jayewardenepura, Nugegoda, Sri Lanka
| | - Dinesh Kankanamge
- Department of Chemistry and Biochemistry, The University of Toledo, Toledo, OH 43606, USA
| | - Kasun Ratnayake
- Department of Chemistry and Biochemistry, The University of Toledo, Toledo, OH 43606, USA; Department of Pharmacology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Dhanushan Wijayaratna
- Department of Chemistry and Biochemistry, The University of Toledo, Toledo, OH 43606, USA
| | - Koshala Olupothage
- Department of Chemistry and Biochemistry, The University of Toledo, Toledo, OH 43606, USA
| | - Sithurandi Ubeysinghe
- Department of Chemistry and Biochemistry, The University of Toledo, Toledo, OH 43606, USA
| | | | - Terence E Hébert
- Department of Pharmacology and Therapeutics, McGill University, Montréal, QC H3G 1Y6, Canada.
| | - Ajith Karunarathne
- Department of Chemistry and Biochemistry, The University of Toledo, Toledo, OH 43606, USA.
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17
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Somatostatin, a Presynaptic Modulator of Glutamatergic Signal in the Central Nervous System. Int J Mol Sci 2021; 22:ijms22115864. [PMID: 34070785 PMCID: PMC8198526 DOI: 10.3390/ijms22115864] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 05/19/2021] [Accepted: 05/26/2021] [Indexed: 01/07/2023] Open
Abstract
Somatostatin is widely diffused in the central nervous system, where it participates to control the efficiency of synaptic transmission. This peptide mainly colocalizes with GABA, in inhibitory, GABA-containing interneurons from which it is actively released in a Ca2+ dependent manner upon application of depolarizing stimuli. Once released in the synaptic cleft, somatostatin acts locally, or it diffuses in the extracellular space through "volume diffusion", a mechanism(s) of distribution which mainly operates in the cerebrospinal fluid and that assures the progression of neuronal signalling from signal-secreting sender structures towards receptor-expressing targeted neurons located extrasynaptically, in a non-synaptic, inter-neuronal form of communication. Somatostatin controls the efficiency of central glutamate transmission by either modulating presynaptically the glutamate exocytosis or by metamodulating the activity of glutamate receptors colocalized and functionally coupled with somatostatin receptors in selected subpopulations of nerve terminals. Deciphering the role of somatostatin in the mechanisms of "volume diffusion" and in the "receptor-receptor interaction" unveils new perspectives in the central role of this fine tuner of synaptic strength, paving the road to new therapeutic approaches for the cure of central disorders.
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18
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Human Somatostatin SST 4 Receptor Transgenic Mice: Construction and Brain Expression Pattern Characterization. Int J Mol Sci 2021; 22:ijms22073758. [PMID: 33916620 PMCID: PMC8038480 DOI: 10.3390/ijms22073758] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Accepted: 03/31/2021] [Indexed: 12/13/2022] Open
Abstract
Somatostatin receptor subtype 4 (SST4) has been shown to mediate analgesic, antidepressant and anti-inflammatory functions without endocrine actions; therefore, it is proposed to be a novel target for drug development. To overcome the species differences of SST4 receptor expression and function between humans and mice, we generated an SST4 humanized mouse line to serve as a translational animal model for preclinical research. A transposon vector containing the hSSTR4 and reporter gene construct driven by the hSSTR4 regulatory elements were created. The vector was randomly inserted in Sstr4-deficient mice. hSSTR4 expression was detected by bioluminescent in vivo imaging of the luciferase reporter predominantly in the brain. RT-qPCR confirmed the expression of the human gene in the brain and various peripheral tissues consistent with the in vivo imaging. RNAscope in situ hybridization revealed the presence of hSSTR4 transcripts in glutamatergic excitatory neurons in the CA1 and CA2 regions of the hippocampus; in the GABAergic interneurons in the granular layer of the olfactory bulb and in both types of neurons in the primary somatosensory cortex, piriform cortex, prelimbic cortex and amygdala. This novel SST4 humanized mouse line might enable us to investigate the differences of human and mouse SST4 receptor expression and function and assess the effects of SST4 receptor agonist drug candidates.
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Abstract
Already for centuries, humankind is driven to understand the physiological and pathological mechanisms that occur in our brains. Today, we know that ion channels play an essential role in the regulation of neural processes and control many functions of the central nervous system. Ion channels present a diverse group of membrane-spanning proteins that allow ions to penetrate the insulating cell membrane upon opening of their channel pores. This regulated ion permeation results in different electrical and chemical signals that are necessary to maintain physiological excitatory and inhibitory processes in the brain. Therefore, it is no surprise that disturbances in the functions of cerebral ion channels can result in a plethora of neurological disorders, which present a tremendous health care burden for our current society. The identification of ion channel-related brain disorders also fuel the research into the roles of ion channel proteins in various brain states. In the last decade, mounting evidence has been collected that indicates a pivotal role for transient receptor potential (TRP) ion channels in the development and various physiological functions of the central nervous system. For instance, TRP channels modulate neurite growth, synaptic plasticity and integration, and are required for neuronal survival. Moreover, TRP channels are involved in numerous neurological disorders. TRPM3 belongs to the melastatin subfamily of TRP channels and represents a non-selective cation channel that can be activated by several different stimuli, including the neurosteroid pregnenolone sulfate, osmotic pressures and heat. The channel is best known as a peripheral nociceptive ion channel that participates in heat sensation. However, recent research identifies TRPM3 as an emerging new player in the brain. In this review, we summarize the available data regarding the roles of TRPM3 in the brain, and correlate these data with the neuropathological processes in which this ion channel may be involved.
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Affiliation(s)
- Katharina Held
- Laboratory of Endometrium, Endometriosis and Reproductive Medicine, Department of Development and Regeneration, KU Leuven, Leuven, Belgium
- Laboratory of Ion Channel Research, Department of Cellular and Molecular Medicine and VIB-KU Leuven Center for Brain and Disease Research, KU Leuven, Leuven, Belgium
| | - Balázs István Tóth
- Laboratory of Cellular and Molecular Physiology, Department of Physiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
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20
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Zhang Y, Wu N, Li Q, Hu X, Wang L, Sun JG, Wang Z, Sun XH. Neuroprotective effect of the somatostatin receptor 5 agonist L-817,818 on retinal ganglion cells in experimental glaucoma. Exp Eye Res 2021; 204:108449. [PMID: 33465395 DOI: 10.1016/j.exer.2021.108449] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 12/04/2020] [Accepted: 01/12/2021] [Indexed: 02/06/2023]
Abstract
Somatostatin plays important roles in modulating neuronal functions by activating the five specific G-protein coupled receptors (sst1-sst5). Previous studies have demonstrated that sst5 were expressed in retinal ganglion cells (RGCs) and sst5 agonist attenuated the α-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid-induced retinal neurotoxicity. In this study, we investigated effects and underlying mechanisms of the sst5 agonist L-817,818 on RGC injury induced by elevated intraocular pressure (COH) in experimental glaucoma. Our results showed that intraperitoneal administration of L-817,818 significantly reduced RGC loss and decreased the number of terminal deoxynucleotidyl transferase mediated dUTP nick-end labeling (TUNEL)-positive RGCs in COH retinas, suggesting that L-817,818 may attenuate RGC apoptosis. Consistently, in COH retinas with L-817,818 administration, both the down-regulated mRNA and protein levels of anti-apoptotic Bcl-2 and the up-regulated mRNA and protein levels of pro-apoptotic Bax were partially reversed. L-817,818 administration downregulated the expression of apoptosis-related proteins caspase-9 and caspase-3 in COH retinas. In addition, L-817,818 administration reduced the concentrations of reactive oxygen species/reactive nitrogen species and malondialdehyde, and ameliorated the functions of mitochondrial respiratory chain complex (MRCC). Our results imply that administration of the sst5 agonist L-817,818 reduces RGC loss in COH rats through decreasing RGC apoptosis, which is mediated by regulating Bcl-2/Bax balance, reducing oxidative stress and rescuing activities of MRCC. Activation of sst5 may provide neuroprotective roles for RGCs in glaucoma.
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Affiliation(s)
- Yi Zhang
- Eye Institute and Department of Ophthalmology, Eye & ENT Hospital, NHC Key Laboratory of Myopia, Shanghai Key Laboratory of Visual Impairment and Restoration, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, China
| | - Na Wu
- Eye Institute and Department of Ophthalmology, Eye & ENT Hospital, NHC Key Laboratory of Myopia, Shanghai Key Laboratory of Visual Impairment and Restoration, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, China
| | - Qian Li
- Eye Institute and Department of Ophthalmology, Eye & ENT Hospital, NHC Key Laboratory of Myopia, Shanghai Key Laboratory of Visual Impairment and Restoration, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, China
| | - Xin Hu
- Department of Ophthalmology, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Li Wang
- Eye Institute and Department of Ophthalmology, Eye & ENT Hospital, NHC Key Laboratory of Myopia, Shanghai Key Laboratory of Visual Impairment and Restoration, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, China
| | - Jian-Guo Sun
- Eye Institute and Department of Ophthalmology, Eye & ENT Hospital, NHC Key Laboratory of Myopia, Shanghai Key Laboratory of Visual Impairment and Restoration, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, China
| | - Zhongfeng Wang
- Department of Ophthalmology, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Zhongshan Hospital, Fudan University, Shanghai, China.
| | - Xing-Huai Sun
- Eye Institute and Department of Ophthalmology, Eye & ENT Hospital, NHC Key Laboratory of Myopia, Shanghai Key Laboratory of Visual Impairment and Restoration, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, China.
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21
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Prevot TD, Sumitomo A, Tomoda T, Knutson DE, Li G, Mondal P, Banasr M, Cook JM, Sibille E. Reversal of Age-Related Neuronal Atrophy by α5-GABAA Receptor Positive Allosteric Modulation. Cereb Cortex 2021; 31:1395-1408. [PMID: 33068001 PMCID: PMC7786363 DOI: 10.1093/cercor/bhaa310] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Revised: 09/20/2020] [Accepted: 09/21/2020] [Indexed: 12/30/2022] Open
Abstract
Aging is associated with reduced brain volume, altered neural activity, and neuronal atrophy in cortical-like structures, comprising the frontal cortex and hippocampus, together contributing to cognitive impairments. Therapeutic efforts aimed at reversing these deficits have focused on excitatory or neurotrophic mechanisms, although recent findings show that reduced dendritic inhibition mediated by α5-subunit containing GABA-A receptors (α5-GABAA-Rs) occurs during aging and contributes to cognitive impairment. Here, we aimed to confirm the beneficial effect on working memory of augmenting α5-GABAA-R activity in old mice and tested its potential at reversing age-related neuronal atrophy. We show that GL-II-73, a novel ligand with positive allosteric modulatory activity at α5-GABAA-R (α5-PAM), increases dendritic branching complexity and spine numbers of cortical neurons in vitro. Using old mice, we confirm that α5-PAM reverses age-related working memory deficits and show that chronic treatment (3 months) significantly reverses age-related dendritic shrinkage and spine loss in frontal cortex and hippocampus. A subsequent 1-week treatment cessation (separate cohort) resulted in loss of efficacy on working memory but maintained morphological neurotrophic effects. Together, the results demonstrate the beneficial effect on working memory and neurotrophic efficacy of augmenting α5-GABAA-R function in old mice, suggesting symptomatic and disease-modifying potential in age-related brain disorders.
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Affiliation(s)
- Thomas D Prevot
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON M5T 1R8, Canada
| | - Akiko Sumitomo
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON M5T 1R8, Canada
| | - Toshifumi Tomoda
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON M5T 1R8, Canada
| | - Daniel E Knutson
- Department of Chemistry and Biochemistry, University of Wisconsin–Milwaukee, Milwaukee, WI 53211, USA
| | - Guanguan Li
- Department of Chemistry and Biochemistry, University of Wisconsin–Milwaukee, Milwaukee, WI 53211, USA
| | - Prithu Mondal
- Department of Chemistry and Biochemistry, University of Wisconsin–Milwaukee, Milwaukee, WI 53211, USA
| | - Mounira Banasr
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON M5T 1R8, Canada
- Department of Psychiatry, University of Toronto, Toronto, ON M5T 1R8, Canada
- Department of Pharmacology and Toxicology, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - James M Cook
- Department of Chemistry and Biochemistry, University of Wisconsin–Milwaukee, Milwaukee, WI 53211, USA
| | - Etienne Sibille
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON M5T 1R8, Canada
- Department of Psychiatry, University of Toronto, Toronto, ON M5T 1R8, Canada
- Department of Pharmacology and Toxicology, University of Toronto, Toronto, ON M5S 1A8, Canada
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Rofo F, Ugur Yilmaz C, Metzendorf N, Gustavsson T, Beretta C, Erlandsson A, Sehlin D, Syvänen S, Nilsson P, Hultqvist G. Enhanced neprilysin-mediated degradation of hippocampal Aβ42 with a somatostatin peptide that enters the brain. Am J Cancer Res 2021; 11:789-804. [PMID: 33391505 PMCID: PMC7738863 DOI: 10.7150/thno.50263] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Accepted: 10/13/2020] [Indexed: 12/21/2022] Open
Abstract
Background: Aggregation of the amyloid-beta (Aβ) peptide is one of the main neuropathological events in Alzheimer's disease (AD). Neprilysin is the major enzyme degrading Aβ, with its activity enhanced by the neuropeptide somatostatin (SST). SST levels are decreased in the brains of AD patients. The poor delivery of SST over the blood-brain barrier (BBB) and its extremely short half-life of only 3 min limit its therapeutic significance. Methods: We recombinantly fused SST to a BBB transporter binding to the transferrin receptor. Using primary neuronal cultures and neuroblastoma cell lines, the ability of the formed fusion protein to activate neprilysin was studied. SST-scFv8D3 was administered to mice overexpressing the Aβ-precursor protein (AβPP) with the Swedish mutation (APPswe) as a single injection or as a course of three injections over a 72 h period. Levels of neprilysin and Aβ were quantified using an Enzyme-linked immunosorbent assay (ELISA). Distribution of SST-scFv8D3 in the brain, blood and peripheral organs was studied by radiolabeling with iodine-125. Results: The construct, SST-scFv8D3, exhibited 120 times longer half-life than SST alone, reached the brain in high amounts when injected intravenously and significantly increased the brain concentration of neprilysin in APPswe mice. A significant decrease in the levels of membrane-bound Aβ42 was detected in the hippocampus and the adjacent cortical area after only three injections. Conclusion: With intravenous injections of our BBB permeable SST peptide, we were able to significantly increase the levels neprilysin, an effect that was followed by a significant and selective degradation of membrane-bound Aβ42 in the hippocampus. Being that membrane-bound Aβ triggers neuronal toxicity and the hippocampus is the central brain area in the progression of AD, the study has illuminated a new potential treatment paradigm with a promising safety profile targeting only the disease affected areas.
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Characterization of Neurons Expressing the Novel Analgesic Drug Target Somatostatin Receptor 4 in Mouse and Human Brains. Int J Mol Sci 2020; 21:ijms21207788. [PMID: 33096776 PMCID: PMC7589422 DOI: 10.3390/ijms21207788] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Revised: 10/08/2020] [Accepted: 10/16/2020] [Indexed: 12/13/2022] Open
Abstract
Somatostatin is an important mood and pain-regulating neuropeptide, which exerts analgesic, anti-inflammatory, and antidepressant effects via its Gi protein-coupled receptor subtype 4 (SST4) without endocrine actions. SST4 is suggested to be a unique novel drug target for chronic neuropathic pain, and depression, as a common comorbidity. However, its neuronal expression and cellular mechanism are poorly understood. Therefore, our goals were (i) to elucidate the expression pattern of Sstr4/SSTR4 mRNA, (ii) to characterize neurochemically, and (iii) electrophysiologically the Sstr4/SSTR4-expressing neuronal populations in the mouse and human brains. Here, we describe SST4 expression pattern in the nuclei of the mouse nociceptive and anti-nociceptive pathways as well as in human brain regions, and provide neurochemical and electrophysiological characterization of the SST4-expressing neurons. Intense or moderate SST4 expression was demonstrated predominantly in glutamatergic neurons in the major components of the pain matrix mostly also involved in mood regulation. The SST4 agonist J-2156 significantly decreased the firing rate of layer V pyramidal neurons by augmenting the depolarization-activated, non-inactivating K+ current (M-current) leading to remarkable inhibition. These are the first translational results explaining the mechanisms of action of SST4 agonists as novel analgesic and antidepressant candidates.
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24
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Mosleh E, Ou K, Haemmerle MW, Tembo T, Yuhas A, Carboneau BA, Townsend SE, Bosma KJ, Gannon M, O’Brien RM, Stoffers DA, Golson ML. Ins1-Cre and Ins1-CreER Gene Replacement Alleles Are Susceptible To Silencing By DNA Hypermethylation. Endocrinology 2020; 161:5817889. [PMID: 32267917 PMCID: PMC7354059 DOI: 10.1210/endocr/bqaa054] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Accepted: 04/07/2020] [Indexed: 12/14/2022]
Abstract
Targeted gene ablation studies of the endocrine pancreas have long suffered from suboptimal Cre deleter strains. In many cases, Cre lines purportedly specific for beta cells also displayed expression in other islet endocrine cells or in a subset of neurons in the brain. Several pancreas and endocrine Cre lines have experienced silencing or mosaicism over time. In addition, many Cre transgenic constructs were designed to include the hGH mini-gene, which by itself increases beta-cell replication and decreases beta-cell function. More recently, driver lines with Cre or CreER inserted into the Ins1 locus were generated, with the intent of producing β cell-specific Cre lines with faithful recapitulation of insulin expression. These lines were bred in multiple labs to several different mouse lines harboring various lox alleles. In our hands, the ability of the Ins1-Cre and Ins1-CreER lines to delete target genes varied from that originally reported, with both alleles displaying low levels of expression, increased levels of methylation compared to the wild-type allele, and ultimately inefficient or absent target deletion. Thus, caution is warranted in the interpretation of results obtained with these genetic tools, and Cre expression and activity should be monitored regularly when using these lines.
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Affiliation(s)
- Elham Mosleh
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
- Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Kristy Ou
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
- Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Matthew W Haemmerle
- Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Teguru Tembo
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
- Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Andrew Yuhas
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
- Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Bethany A Carboneau
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, Tennessee
| | - Shannon E Townsend
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, Tennessee
| | - Karin J Bosma
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, Tennessee
| | - Maureen Gannon
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, Tennessee
- Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee
- United States Department of Veteran Affairs, Nashville, Tennessee
| | - Richard M O’Brien
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, Tennessee
| | - Doris A Stoffers
- Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
- Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Maria L Golson
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
- Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
- Department of Medicine, Johns Hopkins School of Medicine, Baltimore, Maryland
- Correspondence: Maria L. Golson, PhD, 5501 Hopkins Bayview Circle, Baltimore, MD 21224. E-mail:
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25
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Alshafie W, Francis V, Bednarz K, Pan YE, Stroh T, McPherson PS. Regulated resurfacing of a somatostatin receptor storage compartment fine-tunes pituitary secretion. J Cell Biol 2020; 219:132745. [PMID: 31825461 PMCID: PMC7039187 DOI: 10.1083/jcb.201904054] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Revised: 07/26/2019] [Accepted: 10/25/2019] [Indexed: 12/15/2022] Open
Abstract
In pituitary cells, internalized somatostatin receptor is held in a GLUT4-like storage compartment. The receptor rapidly resurfaces in response to selective signaling pathways in a process that fine-tunes pituitary hormone release. The surfacing of the glucose transporter GLUT4 driven by insulin receptor activation provides the prototypic example of a homeostasis response dependent on mobilization of an intracellular storage compartment. Here, we generalize this concept to a G protein–coupled receptor, somatostatin receptor subtype 2 (SSTR2), in pituitary cells. Following internalization in corticotropes, SSTR2 moves to a juxtanuclear syntaxin-6–positive compartment, where it remains until the corticotropes are stimulated with corticotropin releasing factor (CRF), whereupon SSTR2 exits the compartment on syntaxin-6–positive vesicular/tubular carriers that depend on Rab10 for their fusion with the plasma membrane. As SSTR2 activation antagonizes CRF-mediated hormone release, this storage/resurfacing mechanism may allow for a physiological homeostatic feedback system. In fact, we find that SSTR2 moves from an intracellular compartment to the cell surface in pituitary gland somatotropes, concomitant with increasing levels of serum growth hormone (GH) during natural GH cycles. Our data thus provide a mechanism by which signaling-mediated plasma membrane resurfacing of SSTR2 can fine-tune pituitary hormone release.
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Affiliation(s)
- Walaa Alshafie
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
| | - Vincent Francis
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
| | - Klaudia Bednarz
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
| | - Yingzhou Edward Pan
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
| | - Thomas Stroh
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
| | - Peter S McPherson
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
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26
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Gomes-Porras M, Cárdenas-Salas J, Álvarez-Escolá C. Somatostatin Analogs in Clinical Practice: a Review. Int J Mol Sci 2020; 21:ijms21051682. [PMID: 32121432 PMCID: PMC7084228 DOI: 10.3390/ijms21051682] [Citation(s) in RCA: 106] [Impact Index Per Article: 26.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Revised: 02/22/2020] [Accepted: 02/25/2020] [Indexed: 12/14/2022] Open
Abstract
Somatostatin analogs are an invaluable therapeutic option in the diagnosis and treatment of somatotropinomas, thyrotropinomas, and functioning and non-functioning gastroenteropancreatic neuroendocrine tumors. They should also be considered an effective and safe therapeutic alternative to corticotropinomas, gonadotropinomas, and prolactinomas resistant to dopamine agonists. Somatostatin analogs have also shown to be useful in the treatment of other endocrine diseases (congenital hyperinsulinism, Graves’ orbitopathy, diabetic retinopathy, diabetic macular edema), non-endocrine tumors (breast, colon, prostate, lung, and hepatocellular), and digestive diseases (chronic refractory diarrhea, hepatorenal polycystosis, gastrointestinal hemorrhage, dumping syndrome, and intestinal fistula).
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Affiliation(s)
- Mariana Gomes-Porras
- Department of Endocrinology, “La Paz” University Hospital. Paseo de la Castellana, 261, 28046 Madrid, Spain;
| | - Jersy Cárdenas-Salas
- Department of Endocrinology, “Fundación Jiménez-Diaz” University Hospital. Av. de los Reyes Católicos, 2, 28040 Madrid, Spain;
| | - Cristina Álvarez-Escolá
- Department of Endocrinology, “La Paz” University Hospital. Paseo de la Castellana, 261, 28046 Madrid, Spain;
- Correspondence: ; Tel.: +34-917-277-209
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27
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Liao X, Cai F, Sun Z, Zhang Y, Wang J, Jiao B, Guo J, Li J, Liu X, Guo L, Zhou Y, Wang J, Yan X, Jiang H, Xia K, Li J, Tang B, Shen L, Song W. Identification of Alzheimer's disease-associated rare coding variants in the ECE2 gene. JCI Insight 2020; 5:135119. [PMID: 32102983 DOI: 10.1172/jci.insight.135119] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Accepted: 01/29/2020] [Indexed: 11/17/2022] Open
Abstract
Accumulation of amyloid β protein (Aβ) due to increased generation and/or impaired degradation plays an important role in Alzheimer's disease (AD) pathogenesis. In this report, we describe the identification of rare coding mutations in the endothelin-converting enzyme 2 (ECE2) gene in 1 late-onset AD family, and additional case-control cohort analysis indicates ECE2 variants associated with the risk of developing AD. The 2 mutations (R186C and F751S) located in the peptidase domain in the ECE2 protein were found to severely impair the enzymatic activity of ECE2 in Aβ degradation. We further evaluated the effect of the R186C mutation in mutant APP-knockin mice. Overexpression of wild-type ECE2 in the hippocampus reduced amyloid load and plaque formation, and improved learning and memory deficits in the AD model mice. However, the effect was abolished by the R186C mutation in ECE2. Taken together, the results demonstrated that ECE2 peptidase mutations contribute to AD pathogenesis by impairing Aβ degradation, and overexpression of ECE2 alleviates AD phenotypes. This study indicates that ECE2 is a risk gene for AD development and pharmacological activation of ECE2 could be a promising strategy for AD treatment.
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Affiliation(s)
- Xinxin Liao
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, Hunan, China.,Townsend Family Laboratories, Department of Psychiatry, The University of British Columbia, Vancouver, Canada.,National Clinical Research Center for Geriatric Disorders
| | - Fang Cai
- Townsend Family Laboratories, Department of Psychiatry, The University of British Columbia, Vancouver, Canada
| | - Zhanfang Sun
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, Hunan, China.,National Clinical Research Center for Geriatric Disorders
| | - Yun Zhang
- Townsend Family Laboratories, Department of Psychiatry, The University of British Columbia, Vancouver, Canada
| | - Juelu Wang
- Townsend Family Laboratories, Department of Psychiatry, The University of British Columbia, Vancouver, Canada
| | - Bin Jiao
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, Hunan, China.,National Clinical Research Center for Geriatric Disorders
| | - Jifeng Guo
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, Hunan, China.,National Clinical Research Center for Geriatric Disorders.,Key Laboratory of Hunan Province in Neurodegenerative Disorders, Central South University, Changsha, Hunan, China
| | - Jinchen Li
- National Clinical Research Center for Geriatric Disorders
| | - Xixi Liu
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, Hunan, China.,National Clinical Research Center for Geriatric Disorders
| | - Lina Guo
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, Hunan, China.,National Clinical Research Center for Geriatric Disorders
| | - Yafang Zhou
- National Clinical Research Center for Geriatric Disorders
| | - Junling Wang
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, Hunan, China.,National Clinical Research Center for Geriatric Disorders
| | - Xinxiang Yan
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, Hunan, China.,National Clinical Research Center for Geriatric Disorders
| | - Hong Jiang
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, Hunan, China.,National Clinical Research Center for Geriatric Disorders.,Key Laboratory of Hunan Province in Neurodegenerative Disorders, Central South University, Changsha, Hunan, China
| | - Kun Xia
- School of Life Sciences, and
| | | | - Beisha Tang
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, Hunan, China.,National Clinical Research Center for Geriatric Disorders.,Key Laboratory of Hunan Province in Neurodegenerative Disorders, Central South University, Changsha, Hunan, China
| | - Lu Shen
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, Hunan, China.,National Clinical Research Center for Geriatric Disorders.,Key Laboratory of Hunan Province in Neurodegenerative Disorders, Central South University, Changsha, Hunan, China
| | - Weihong Song
- Townsend Family Laboratories, Department of Psychiatry, The University of British Columbia, Vancouver, Canada
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28
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Somatostatin receptor 5-mediated modulation of outward K+ currents in rat retinal ganglion cells. Neuroreport 2020; 31:131-138. [DOI: 10.1097/wnr.0000000000001402] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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29
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Sandoval K, Umbaugh D, House A, Crider A, Witt K. Somatostatin Receptor Subtype-4 Regulates mRNA Expression of Amyloid-Beta Degrading Enzymes and Microglia Mediators of Phagocytosis in Brains of 3xTg-AD Mice. Neurochem Res 2019; 44:2670-2680. [PMID: 31630317 DOI: 10.1007/s11064-019-02890-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Revised: 09/06/2019] [Accepted: 10/03/2019] [Indexed: 02/06/2023]
Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative disorder resulting in memory and cognitive impairment. The use of somatostatin receptor subtype-4 (SSTR4) agonists have been proposed for AD treatment. This study investigated the effects of selective SSTR4 agonist NNC 26-9100 on mRNA expression of key genes associated with AD pathology (microglia mediators of Aβ phagocytosis, amyloid-beta (Aβ)-degrading enzymes, anti-oxidant enzymes and pro-inflammatory cytokines) in 3xTg-AD mice. Mice were administered NNC 26-9100 (0.2 µg, i.c.v.) or vehicle control, with cortical and subcortical brain tissue collected at 6 h and 24 h post-treatment. At 6 h, NNC 26-9100 treatment decreased cortical expression of cluster of differentiation-33 (Cd33) by 25%, while increasing cortical and subcortical macrophage scavenger receptor-1 (Msr1) by 1.8 and 2.0-fold, respectively. The Cd33 downregulation and Msr1 upregulation support a state of microglia associated Aβ phagocytosis. At 24 h, NNC 26-9100 treatment increased the cortical expression of Sstr4 (4.9-fold), Aβ-degrading enzymes neprilysin (9.3-fold) and insulin degrading enzyme (14.8-fold), and the antioxidant catalase (3.6-fold). Similar effects at 24 h were found in subcortical tissue with NNC 26-9100 treatment, but did not reach statistical significance. No changes in pro-inflammatory cytokine expression were found. These data demonstrated NNC 26-9100 facilitates transcriptional changes in brain tissue identified with Aβ phagocytosis and clearance, further supporting SSTR4 as a treatment target for AD.
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Affiliation(s)
- Karin Sandoval
- Department of Pharmaceutical Sciences Pharmaceutical Sciences, School of Pharmacy, Southern Illinois University Edwardsville, 200 University Park Drive., Building 220, Edwardsville, IL, 62025, USA
| | - David Umbaugh
- Department of Pharmaceutical Sciences Pharmaceutical Sciences, School of Pharmacy, Southern Illinois University Edwardsville, 200 University Park Drive., Building 220, Edwardsville, IL, 62025, USA
| | - Austin House
- Department of Pharmaceutical Sciences Pharmaceutical Sciences, School of Pharmacy, Southern Illinois University Edwardsville, 200 University Park Drive., Building 220, Edwardsville, IL, 62025, USA
| | - Albert Crider
- Department of Pharmaceutical Sciences Pharmaceutical Sciences, School of Pharmacy, Southern Illinois University Edwardsville, 200 University Park Drive., Building 220, Edwardsville, IL, 62025, USA
| | - Ken Witt
- Department of Pharmaceutical Sciences Pharmaceutical Sciences, School of Pharmacy, Southern Illinois University Edwardsville, 200 University Park Drive., Building 220, Edwardsville, IL, 62025, USA.
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30
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Miyata S, Kumagaya R, Kakizaki T, Fujihara K, Wakamatsu K, Yanagawa Y. Loss of Glutamate Decarboxylase 67 in Somatostatin-Expressing Neurons Leads to Anxiety-Like Behavior and Alteration in the Akt/GSK3β Signaling Pathway. Front Behav Neurosci 2019; 13:131. [PMID: 31275123 PMCID: PMC6591520 DOI: 10.3389/fnbeh.2019.00131] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Accepted: 06/04/2019] [Indexed: 12/15/2022] Open
Abstract
Major depressive disorder (MDD) is a highly prevalent psychiatric disorder worldwide. Several lines of evidence suggest that the dysfunction of somatostatin (SOM) neurons is associated with the pathophysiology of MDD. Importantly, most SOM neurons are γ-aminobutyric acid (GABA) interneurons. However, whether the dysfunction of GABAergic neurotransmission from SOM neurons contributes to the pathophysiology of MDD remains elusive. To address this issue, we investigated the emotional behaviors and relevant molecular mechanism in mice lacking glutamate decarboxylase 67 (GAD67), an isoform of GABA-synthesizing enzyme, specifically in SOM neurons (SOM-GAD67 mice). The SOM-GAD67 mice exhibited anxiety-like behavior in the open-field test without an effect on locomotor activity. The SOM-GAD67 mice showed depression-like behavior in neither the forced swimming test nor the sucrose preference test. In addition, the ability to form contextual fear memory was normal in the SOM-GAD67 mice. Furthermore, the plasma corticosterone level was normal in the SOM-GAD67 mice both under baseline and stress conditions. The expression ratios of p-AktSer473/Akt and p-GSK3βSer9/GSK3β were decreased in the frontal cortex of SOM-GAD67 mice. Taken together, these data suggest that the loss of GAD67 from SOM neurons may lead to the development of anxiety-like but not depression-like states mediated by modification of Akt/GSK3β activities.
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Affiliation(s)
- Shigeo Miyata
- Department of Genetic and Behavioral Neuroscience, Graduate School of Medicine, Gunma University, Maebashi, Japan
| | - Ryota Kumagaya
- Division of Molecular Science, Graduate School of Science and Technology, Gunma University, Kiryu, Japan
| | - Toshikazu Kakizaki
- Department of Genetic and Behavioral Neuroscience, Graduate School of Medicine, Gunma University, Maebashi, Japan
| | - Kazuyuki Fujihara
- Department of Genetic and Behavioral Neuroscience, Graduate School of Medicine, Gunma University, Maebashi, Japan
| | - Kaori Wakamatsu
- Division of Molecular Science, Graduate School of Science and Technology, Gunma University, Kiryu, Japan
| | - Yuchio Yanagawa
- Department of Genetic and Behavioral Neuroscience, Graduate School of Medicine, Gunma University, Maebashi, Japan
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31
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Solarski M, Williams D, Mehrabian M, Wang H, Wille H, Schmitt-Ulms G. The human brain somatostatin interactome: SST binds selectively to P-type family ATPases. PLoS One 2019; 14:e0217392. [PMID: 31136617 PMCID: PMC6538167 DOI: 10.1371/journal.pone.0217392] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2018] [Accepted: 05/11/2019] [Indexed: 11/18/2022] Open
Abstract
Somatostatin (SST) is a cyclic peptide that is understood to inhibit the release of hormones and neurotransmitters from a variety of cells by binding to one of five canonical G protein-coupled SST receptors (SSTR1 to SSTR5). Recently, SST was also observed to interact with the amyloid beta (Aβ) peptide and affect its aggregation kinetics, raising the possibility that it may bind other brain proteins. Here we report on an SST interactome analysis that made use of human brain extracts as biological source material and incorporated advanced mass spectrometry workflows for the relative quantitation of SST binding proteins. The analysis revealed SST to predominantly bind several members of the P-type family of ATPases. Subsequent validation experiments confirmed an interaction between SST and the sodium-potassium pump (Na+/K+-ATPase) and identified a tryptophan residue within SST as critical for binding. Functional analyses in three different cell lines indicated that SST might negatively modulate the K+ uptake rate of the Na+/K+-ATPase.
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Affiliation(s)
- Michael Solarski
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Krembil Discovery Centre, Toronto, Ontario, Canada
| | - Declan Williams
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Krembil Discovery Centre, Toronto, Ontario, Canada
| | - Mohadeseh Mehrabian
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Krembil Discovery Centre, Toronto, Ontario, Canada
| | - Hansen Wang
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Krembil Discovery Centre, Toronto, Ontario, Canada
| | - Holger Wille
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada
| | - Gerold Schmitt-Ulms
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Krembil Discovery Centre, Toronto, Ontario, Canada
- Department of Laboratory Medicine & Pathobiology, University of Toronto, Toronto, Ontario, Canada
- * E-mail:
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32
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Subclinical lipopolysaccharide from Salmonella Enteritidis induces neuropeptide dysregulation in the spinal cord and the dorsal root ganglia. BMC Neurosci 2019; 20:18. [PMID: 31023212 PMCID: PMC6485123 DOI: 10.1186/s12868-019-0502-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Accepted: 04/18/2019] [Indexed: 12/13/2022] Open
Abstract
Background Despite increasing evidence that lipopolysaccharide (LPS) affects the biological active substances of dorsal root ganglia (DRG) we have limited knowledge of the influence of a single low dose of LPS, which does not result in any clinical symptoms of disease (subclinical LPS) on neuropeptides connected with the sensory pathway. Accordingly, in this work, we investigated the influence of subclinical LPS from Salmonella Enteritidis on selected neuropeptides: substance P (SP), galanin (GAL), neuropeptide Y (NPY), vasoactive intestinal peptide (VIP) and somatostatin (SOM) in the cervical, thoracic, lumbar and sacral regions of the DRG and spinal cord. Methods This study was performed on immature female pigs of the Pietrain × Duroc breed. Seven days after the intravenous injection of saline solution for control animals (n = 5) and 5 μg/kg b.w. LPS from S. Enteritidis for the experimental group (n = 5), the DRG and the spinal cord were collected to extract the neuropeptides using solid-phase extraction technology. Results Our results demonstrated that subclinical LPS in DRG was able to change the levels of all studied neuropeptides except SOM, whereas in the spinal cord it down-regulated all studied neuropeptides in the sacral spinal cord, maintaining the concentration of all studied neuropeptides in other regions similar to that observed in the control animals. The significant differences in the intensity and character of observed changes between particular regions of the DRG suggest that the exact functions of the studied neuropeptides and mechanisms of responses to subclinical LPS action depend on specific characteristics and functions of each examination region of DRG. Conclusions The mechanisms of observed changes are not fully understood and require further study of the molecular interactions between subclinical LPS from S. Enteritidis and neuronal and non-neuronal cells of DRG and spinal cord. The peripheral and central pain pathways must be analysed with the aspect of unknown long-term consequences of the influence of subclinical LPS from S. Enteritidis on neuropeptides in the spinal cord and the dorsal root ganglia.
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33
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Nocera S, Simon A, Fiquet O, Chen Y, Gascuel J, Datiche F, Schneider N, Epelbaum J, Viollet C. Somatostatin Serves a Modulatory Role in the Mouse Olfactory Bulb: Neuroanatomical and Behavioral Evidence. Front Behav Neurosci 2019; 13:61. [PMID: 31024270 PMCID: PMC6465642 DOI: 10.3389/fnbeh.2019.00061] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Accepted: 03/12/2019] [Indexed: 11/30/2022] Open
Abstract
Somatostatin (SOM) and somatostatin receptors (SSTR1-4) are present in all olfactory structures, including the olfactory bulb (OB), where SOM modulates physiological gamma rhythms and olfactory discrimination responses. In this work, histological, viral tracing and transgenic approaches were used to characterize SOM cellular targets in the murine OB. We demonstrate that SOM targets all levels of mitral dendritic processes in the OB with somatostatin receptor 2 (SSTR2) detected in the dendrites of previously uncharacterized mitral-like cells. We show that inhibitory interneurons of the glomerular layer (GL) express SSTR4 while SSTR3 is confined to the granule cell layer (GCL). Furthermore, SOM cells in the OB receive synaptic inputs from olfactory cortical afferents. Behavioral studies demonstrate that genetic deletion of SSTR4, SSTR2 or SOM differentially affects olfactory performance. SOM or SSTR4 deletion have no major effect on olfactory behavioral performances while SSTR2 deletion impacts olfactory detection and discrimination behaviors. Altogether, these results describe novel anatomical and behavioral contributions of SOM, SSTR2 and SSTR4 receptors in olfactory processing.
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Affiliation(s)
- Sonia Nocera
- INSERM, UMR 894-Center for Psychiatry and Neuroscience (CPN), Paris, France
- Université Paris Descartes-Sorbonne Paris Cité, Paris, France
| | - Axelle Simon
- INSERM, UMR 894-Center for Psychiatry and Neuroscience (CPN), Paris, France
- Université Paris Descartes-Sorbonne Paris Cité, Paris, France
| | - Oriane Fiquet
- INSERM, UMR 894-Center for Psychiatry and Neuroscience (CPN), Paris, France
- Université Paris Descartes-Sorbonne Paris Cité, Paris, France
| | - Ying Chen
- INSERM, UMR 894-Center for Psychiatry and Neuroscience (CPN), Paris, France
- Université Paris Descartes-Sorbonne Paris Cité, Paris, France
| | - Jean Gascuel
- CNRS UMR 6265—Centre des Sciences du Goût et de l’Alimentation (CSGA), Dijon, France
| | - Frédérique Datiche
- CNRS UMR 6265—Centre des Sciences du Goût et de l’Alimentation (CSGA), Dijon, France
| | - Nanette Schneider
- CNRS UMR 6265—Centre des Sciences du Goût et de l’Alimentation (CSGA), Dijon, France
| | - Jacques Epelbaum
- INSERM, UMR 894-Center for Psychiatry and Neuroscience (CPN), Paris, France
- Université Paris Descartes-Sorbonne Paris Cité, Paris, France
| | - Cécile Viollet
- INSERM, UMR 894-Center for Psychiatry and Neuroscience (CPN), Paris, France
- Université Paris Descartes-Sorbonne Paris Cité, Paris, France
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Szentes N, Tékus V, Mohos V, Borbély É, Helyes Z. Exploratory and locomotor activity, learning and memory functions in somatostatin receptor subtype 4 gene-deficient mice in relation to aging and sex. GeroScience 2019; 41:631-641. [PMID: 30903571 PMCID: PMC6885027 DOI: 10.1007/s11357-019-00059-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Accepted: 03/08/2019] [Indexed: 02/06/2023] Open
Abstract
The inhibitory neuropeptide somatostatin regulates several functions in the nervous system including memory. Its concentrations decrease by age leading to functional alterations, but there are little known about the receptorial mechanism. We discovered that somatostatin receptor 4 (sst4) mediates analgesic, anti-depressant, and anti-inflammatory effects without endocrine actions, and it is a unique target for drug development. We investigated the exploratory and locomotor activities and learning and memory functions of male and female sst4gene-deficient mice compared with their wild-types (WT) at ages of 3, 12, 17 months in the Y-maze test, open field test (OFT), radial-arm maze (RAM) test and novel object recognition (NOR) test. Young sst4 gene-deficient females visited, repeated, and missed significantly less arms than the WTs in the RAM; males showed decreased exploration in the NOR. Young mice moved significantly more, spend longer time in OFT center, and visited more arms in the Y-maze than older ones. Young WT females spend significantly longer time in the OFT center, visited, missed and repeated more arms of the RAM than males. Old males found more rewards than females. Young males explored longer the novel object than young females and older males in the NOR; the recognition index was smaller in females. We conclude that aging and sex are important factors of behavioral parameters that should be focused on in such studies. Sst4 is likely to influence locomotion and exploratory behavior only in young mice, but not during normal aging, which is a beneficial feature of a good drug target focusing on the elderly.
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Affiliation(s)
- Nikolett Szentes
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, János Szentágothai Research Centre & Centre for Neuroscience, University of Pécs, Szigeti u. 12, Pécs, H-7624, Hungary
| | - Valéria Tékus
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, János Szentágothai Research Centre & Centre for Neuroscience, University of Pécs, Szigeti u. 12, Pécs, H-7624, Hungary
| | - Violetta Mohos
- Department of Pharmacology, Faculty of Pharmacy, University of Pécs, Pécs, Hungary
| | - Éva Borbély
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, János Szentágothai Research Centre & Centre for Neuroscience, University of Pécs, Szigeti u. 12, Pécs, H-7624, Hungary
| | - Zsuzsanna Helyes
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, János Szentágothai Research Centre & Centre for Neuroscience, University of Pécs, Szigeti u. 12, Pécs, H-7624, Hungary. .,PharmInVivo Ltd., Pécs, Hungary.
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35
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Duron E, Vidal JS, Grousselle D, Gabelle A, Lehmann S, Pasquier F, Bombois S, Buée L, Allinquant B, Schraen-Maschke S, Baret C, Rigaud AS, Hanon O, Epelbaum J. Somatostatin and Neuropeptide Y in Cerebrospinal Fluid: Correlations With Amyloid Peptides Aβ 1-42 and Tau Proteins in Elderly Patients With Mild Cognitive Impairment. Front Aging Neurosci 2018; 10:297. [PMID: 30327597 PMCID: PMC6174237 DOI: 10.3389/fnagi.2018.00297] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Accepted: 09/10/2018] [Indexed: 12/23/2022] Open
Abstract
A combination of low cerebrospinal fluid (CSF) Amyloid β1–42 (Aβ1–42) and high Total-Tau (T-Tau) and Phosphorylated-Tau (P-Tau) occurs at a prodromal stage of Alzheimer’s disease (AD) and recent findings suggest that network abnormalities and interneurons dysfunction contribute to cognitive deficits. Somatostatin (SOM) and Neuropeptide Y (NPY) are two neuropeptides which are expressed in GABAergic interneurons with different fates in AD the former only being markedly affected. The aim of this study was to analyze CSF SOM, NPY and CSF Aβ1–42; T-Tau, P-Tau relationships in 43 elderly mild cognitively impairment (MCI) participants from the Biomarker of AmyLoïd pepTide and AlZheimer’s disease Risk (BALTAZAR) cohort. In these samples, CSF SOM and CSF Aβ1–42 on the one hand, and CSF NPY and CSF T-Tau and P-Tau on the other hand are positively correlated. CSF SOM and NPY concentrations should be further investigated to determine if they can stand for early AD biomarkers. Clinical Trial Registration: www.ClinicalTrials.gov, identifier #NCT01315639.
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Affiliation(s)
- Emmanuelle Duron
- AP-HP, Hôpital Broca, Service de Gériatrie, Paris, France.,Université Sorbonne Paris Cité, UMR-S894, INSERM Université Paris Descartes, Centre de Psychiatrie et Neuroscience, Paris, France.,APHP, Hôpital Paul Brousse, Service de Gériatrie du Dr Karoubi, Villejuif, France.,Université Paris-Sud 11, Centre de Recherche en Épidemiologie et Santé des Population- Depression et Antidépresseurs, INSERM UMR-1178, Le Kremlin-Bicêtre, France
| | - Jean-Sébastien Vidal
- AP-HP, Hôpital Broca, Service de Gériatrie, Paris, France.,Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Dominique Grousselle
- Université Sorbonne Paris Cité, UMR-S894, INSERM Université Paris Descartes, Centre de Psychiatrie et Neuroscience, Paris, France
| | - Audrey Gabelle
- Memory Research and Resources Center, Gui de Chauliac Hospital, University of Montpellier, Montpellier, France
| | - Sylvain Lehmann
- Laboratoire de Biochimie Protéomique Clinique, CHU Montpellier, University of Montpellier, INSERM, Montpellier, France
| | - Florence Pasquier
- University of Lille, INSERM 1171, CHU, Centre Mémoire (CMRR) Distalz, Lille, France
| | | | - Luc Buée
- University of Lille, INSERM 1171, CHU, Centre Mémoire (CMRR) Distalz, Lille, France
| | - Bernadette Allinquant
- Université Sorbonne Paris Cité, UMR-S894, INSERM Université Paris Descartes, Centre de Psychiatrie et Neuroscience, Paris, France
| | | | - Christiane Baret
- UF de Neurobiologie, Centre Biologie Pathologie du CHU-Lille, Lille, France
| | - Anne-Sophie Rigaud
- AP-HP, Hôpital Broca, Service de Gériatrie, Paris, France.,Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Olivier Hanon
- AP-HP, Hôpital Broca, Service de Gériatrie, Paris, France.,Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Jacques Epelbaum
- Université Sorbonne Paris Cité, UMR-S894, INSERM Université Paris Descartes, Centre de Psychiatrie et Neuroscience, Paris, France.,MECADEV UMR 7179 CNRS, Muséum National d'Histoire Naturelle, Paris, France
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36
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Duron E, Vidal JS, Grousselle D, Gabelle A, Lehmann S, Pasquier F, Bombois S, Buée L, Allinquant B, Schraen-Maschke S, Baret C, Rigaud AS, Hanon O, Epelbaum J. Somatostatin and Neuropeptide Y in Cerebrospinal Fluid: Correlations With Amyloid Peptides Aβ1–42 and Tau Proteins in Elderly Patients With Mild Cognitive Impairment. Front Aging Neurosci 2018. [DOI: 10.3389/fnagi.2018.00297
expr 920238904 + 834128533] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/16/2023] Open
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37
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Sriroopreddy R, Sajeed R, P R, C S. Differentially expressed gene (DEG) based protein-protein interaction (PPI) network identifies a spectrum of gene interactome, transcriptome and correlated miRNA in nondisjunction Down syndrome. Int J Biol Macromol 2018; 122:1080-1089. [PMID: 30218739 DOI: 10.1016/j.ijbiomac.2018.09.056] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Revised: 09/07/2018] [Accepted: 09/11/2018] [Indexed: 10/28/2022]
Abstract
Down syndrome, a genetic disorder of known attribution reveals several types of brain abnormalities resulting in mental retardation, inadequacy in speech and memory. In this study, we have presented a consolidative network approach to comprehend the intricacy of the associated genes of Down syndrome. In this analysis, the differentially expressed genes (DEG's) were identified and the central networks were constructed as upregulated and downregulated. Subsequently, GNB5, CDC42, SPTAN1, GNG2, GNAZ, PRKACB, SST, CD44, FGF2, PHLPP1, APP, and FYN were identified as the candidate hub genes by using topological parameters. Later, Fpclass a PPI tool identified WASP gene, a co-expression interacting partner with highest network topology. Moreover, an enhanced enrichment pathway namely Opioid signaling was obtained using ClueGo, depicting the roles of the hub genes in signaling and neuronal mechanisms. The transcriptional regulatory factors and the common miRNA connected to them were identified by using MatInspector and miRTarbase. Later, a regulatory network constructed showed that PLAG, T2FB, CREB, NEUR, and GATA were the most commonly connected transcriptional factors and hsa-miR-122-5p was the most prominent miRNA. In a nutshell, these hub genes and the enriched pathway could help understand at a molecular level and eventually used as therapeutic targets for Down syndrome.
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Affiliation(s)
- Ramireddy Sriroopreddy
- Department of Biotechnology, School of Biosciences and Technology, Vellore Institute of Technology, Vellore 632014, India
| | - Rakshanda Sajeed
- Department of Analytics, School of Computer Science and Engineering, Vellore Institute of Technology, Vellore 632014, India
| | - Raghuraman P
- Department of Biotechnology, School of Biosciences and Technology, Vellore Institute of Technology, Vellore 632014, India
| | - Sudandiradoss C
- Department of Biotechnology, School of Biosciences and Technology, Vellore Institute of Technology, Vellore 632014, India.
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38
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Prévôt TD, Viollet C, Epelbaum J, Dominguez G, Béracochéa D, Guillou JL. sst 2-receptor gene deletion exacerbates chronic stress-induced deficits: Consequences for emotional and cognitive ageing. Prog Neuropsychopharmacol Biol Psychiatry 2018; 86:390-400. [PMID: 29409919 DOI: 10.1016/j.pnpbp.2018.01.022] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Revised: 01/17/2018] [Accepted: 01/30/2018] [Indexed: 02/07/2023]
Abstract
This study investigated whether sst2 gene deletion interacts with age and chronic stress exposure to produce exacerbated emotional and cognitive ageing. Middle-aged (10-12 month) sst2 knockout (sst2KO) and wild-type (WT) mice underwent an unpredictable chronic mild stress (UCMS) procedure for 6 weeks or no stress for control groups. This was followed by a battery of tests to assess emotional and cognitive functions and neuroendocrine status (CORT level). A re-evaluation was performed 6 months later (i.e. with 18-month-old mice). UCMS reproduced neuroendocrine and behavioral features of stress-related disorders such as elevated circulating CORT levels, physical deteriorations, increased anxiety- and depressive-like behaviors and working memory impairments. sst2KO mice displayed behavioral alterations which were similar to stressed WT and exhibited exacerbated changes following UCMS exposure. The evaluations performed in the older mice showed significant long-term effects of UCMS exposure. Old sst2KO mice previously exposed to UCMS exhibited spatial learning and memory accuracy impairments and high levels of anxiety-like behaviors which drastically added to the effects of normal ageing. Spatial abilities and emotionality scores (mean z-scores) measured both at the UCMS outcome and 6 months later were correlated with the initially measured CORT levels in middle-age. The present findings indicate that the deletion of the sst2 receptor gene produces chronic hypercorticosteronemia and exacerbates sensitivity to stressors which over time, have consequences on ageing brain function processes.
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Affiliation(s)
- Thomas Damien Prévôt
- Université de Bordeaux, Pessac, France; Centre National de la Recherche Scientifique, UMR 5287, Institut de Neurosciences Cognitives et Intégratives d'Aquitaine, Pessac, France
| | - Cécile Viollet
- Inserm, UMR 894, Center for Psychiatry & Neuroscience, Paris, France; Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Jacques Epelbaum
- Inserm, UMR 894, Center for Psychiatry & Neuroscience, Paris, France; Université Paris Descartes, Sorbonne Paris Cité, Paris, France; UMR 7179 CNRS MNHN - MECADEV, 91800 Brunoy, France
| | - Gaëlle Dominguez
- Centre National de la Recherche Scientifique, UMR 5287, Institut de Neurosciences Cognitives et Intégratives d'Aquitaine, Pessac, France
| | - Daniel Béracochéa
- Université de Bordeaux, Pessac, France; Centre National de la Recherche Scientifique, UMR 5287, Institut de Neurosciences Cognitives et Intégratives d'Aquitaine, Pessac, France
| | - Jean-Louis Guillou
- Université de Bordeaux, Pessac, France; Centre National de la Recherche Scientifique, UMR 5287, Institut de Neurosciences Cognitives et Intégratives d'Aquitaine, Pessac, France.
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39
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Kobayashi M, Hayashi Y, Fujimoto Y, Matsuoka I. Decreased parvalbumin and somatostatin neurons in medial prefrontal cortex in BRINP1-KO mice. Neurosci Lett 2018; 683:82-88. [PMID: 29960053 DOI: 10.1016/j.neulet.2018.06.050] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Revised: 06/11/2018] [Accepted: 06/26/2018] [Indexed: 11/28/2022]
Abstract
BRINPs (BMP/RA-inducible Neural Specific Protein-1, 2, 3) are family genes expressed mainly in both the central and peripheral nervous system. BRINP1 is abundantly expressed in many of adult brain regions including cerebral cortex and hippocampus, with expression regulated in an activity-dependent manner in the dentate gyrus. Mice with disrupted BRINP1 gene exhibit abnormal behaviors such as increased locomotive activity and poor social activity which are analogous to symptoms of human psychiatric disorders such as schizophrenia (SCZ), autism spectrum disorder (ASD) and attention-deficit hyperactivity disorder (ADHD). In the present study, to clarify the physiological roles of BRINP1 in psychiatric disorders, we examined the numbers of parvalbumin (PV)-expressing neurons and somatostatin (SST)-expressing neurons in the medial prefrontal cortex (mPFC) in BRINP1-KO mice. Immunohistochemical analysis revealed the numbers of PV-expressing neurons and SST-expressing neurons in mPFC of BRINP1-KO mice were, respectively, 50% and 20% fewer than corresponding neurons in mPFC of wild-type mice. These data suggest that the abnormal behaviors related to human psychiatric disorders in BRINP1-KO mice could be derived from the hyperexcitability of pyramidal neurons as a consequence of decreased inhibitory innervation and conceivable dysregulation of the Excitatory/Inhibitory balance in mPFC.
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Affiliation(s)
- Miwako Kobayashi
- Laboratory of Physiological Chemistry, College of Pharmaceutical Sciences, Matsuyama University, 4-2 Bunkyo-cho, Matsuyama, Ehime 790-8578, Japan.
| | - Yuichi Hayashi
- Laboratory of Physiological Chemistry, College of Pharmaceutical Sciences, Matsuyama University, 4-2 Bunkyo-cho, Matsuyama, Ehime 790-8578, Japan. f1y--free--
| | - Yuko Fujimoto
- Laboratory of Physiological Chemistry, College of Pharmaceutical Sciences, Matsuyama University, 4-2 Bunkyo-cho, Matsuyama, Ehime 790-8578, Japan.
| | - Ichiro Matsuoka
- Laboratory of Physiological Chemistry, College of Pharmaceutical Sciences, Matsuyama University, 4-2 Bunkyo-cho, Matsuyama, Ehime 790-8578, Japan.
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40
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The Protective Effects of IGF-I against β-Amyloid-related Downregulation of Hippocampal Somatostatinergic System Involve Activation of Akt and Protein Kinase A. Neuroscience 2018; 374:104-118. [PMID: 29406271 DOI: 10.1016/j.neuroscience.2018.01.041] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Revised: 12/14/2017] [Accepted: 01/18/2018] [Indexed: 12/13/2022]
Abstract
Somatostatin (SRIF), a neuropeptide highly distributed in the hippocampus and involved in learning and memory, is markedly reduced in the brain of Alzheimer's disease patients. The effects of insulin-like growth factor-I (IGF-I) against β amyloid (Aβ)-induced neuronal death and associated cognitive disorders have been extensively reported in experimental models of this disease. Here, we examined the effect of IGF-I on the hippocampal somatostatinergic system in Aβ-treated rats and the molecular mechanisms associated with changes in this peptidergic system. Intracerebroventricular Aβ25-35 administration during 14 days (300 pmol/day) to male rats increased Aβ25-35 levels and cell death and markedly reduced SRIF and SRIF receptor 2 levels in the hippocampus. These deleterious effects were associated with reduced Akt and cAMP response element-binding protein (CREB) phosphorylation and activation of c-Jun N-terminal kinase (JNK). Subcutaneous IGF-I co-administration (50 µg/kg/day) reduced hippocampal Aβ25-35 levels, cell death and JNK activation. In addition, IGF-I prevented the reduction in the components of the somatostatinergic system affected by Aβ infusion. Its co-administration also augmented protein kinase A (PKA) activity, as well as Akt and CREB phosphorylation. These results suggest that IGF-I co-administration may have protective effects on the hippocampal somatostatinergic system against Aβ insult through up-regulation of PKA activity and Akt and CREB phosphorylation.
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41
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Marinelli L, Fornasari E, Di Stefano A, Turkez H, Arslan ME, Eusepi P, Ciulla M, Cacciatore I. (R)-α-Lipoyl-Gly-l-Pro-l-Glu dimethyl ester as dual acting agent for the treatment of Alzheimer's disease. Neuropeptides 2017; 66:52-58. [PMID: 28993014 DOI: 10.1016/j.npep.2017.09.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Revised: 09/05/2017] [Accepted: 09/25/2017] [Indexed: 12/17/2022]
Abstract
In this study, effects of LA-GPE (R-α-Lipoyl-Gly-l-Pro-l-Glu dimethyl ester) and GPE (Gly-L-Pro-L-Glu) on the cytotoxic action of Aβ1-42 were tested with differentiated human neuroblastoma SH-SY5Y cells as cellular Alzheimer model via measurements of mitochondrial viability (MTT assay) and lactate dehydrogenase release (LDH assay). Effects of LA-GPE and GPE on acetylcholinesterase (AChE) activity, total antioxidant capacity (TAC) and total oxidative status (TOS) levels, and neural cell apoptosis and necrosis were also determined. In addition, biological safety of these novel formulations was evaluated in human blood cells using different cytotoxicity and genotoxicity assays. Our results indicated that both compounds could block Aβ1-42 induced cell death. LA-GPE reduced Aβ-induced AChE activity and oxidative stress, suggesting it as a multifunctional compound potentially valuable for the treatment of Alzheimer's disease (AD).
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Affiliation(s)
- Lisa Marinelli
- Department of Pharmacy, "G. d'Annunzio" University of Chieti-Pescara, Via dei Vestini 31, Chieti Scalo (CH), Italy
| | - Erika Fornasari
- Department of Pharmacy, "G. d'Annunzio" University of Chieti-Pescara, Via dei Vestini 31, Chieti Scalo (CH), Italy
| | - Antonio Di Stefano
- Department of Pharmacy, "G. d'Annunzio" University of Chieti-Pescara, Via dei Vestini 31, Chieti Scalo (CH), Italy
| | - Hasan Turkez
- Department of Pharmacy, "G. d'Annunzio" University of Chieti-Pescara, Via dei Vestini 31, Chieti Scalo (CH), Italy; Department of Molecular Biology and Genetics, Faculty of Science, Erzurum Technical University, 25240 Erzurum, Turkey
| | - Mehmet Enes Arslan
- Department of Molecular Biology and Genetics, Faculty of Science, Erzurum Technical University, 25240 Erzurum, Turkey
| | - Piera Eusepi
- Department of Pharmacy, "G. d'Annunzio" University of Chieti-Pescara, Via dei Vestini 31, Chieti Scalo (CH), Italy
| | - Michele Ciulla
- Department of Pharmacy, "G. d'Annunzio" University of Chieti-Pescara, Via dei Vestini 31, Chieti Scalo (CH), Italy
| | - Ivana Cacciatore
- Department of Pharmacy, "G. d'Annunzio" University of Chieti-Pescara, Via dei Vestini 31, Chieti Scalo (CH), Italy.
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Pedraza-Arévalo S, Hormaechea-Agulla D, Gómez-Gómez E, Requena MJ, Selth LA, Gahete MD, Castaño JP, Luque RM. Somatostatin receptor subtype 1 as a potential diagnostic marker and therapeutic target in prostate cancer. Prostate 2017; 77:1499-1511. [PMID: 28905400 DOI: 10.1002/pros.23426] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Accepted: 08/23/2017] [Indexed: 12/14/2022]
Abstract
BACKGROUND Prostate cancer (PCa) is a highly prevalent neoplasia that is strongly influenced by the endocrine system. Somatostatin (SST) and its five receptors (sst1-5 encoded by SSTR1-5 genes) comprise a pleiotropic system present in most endocrine-related cancers, some of which are successfully treated with SST analogs. Interestingly, it has been reported that SSTR1 is overexpressed in PCa, but its regulation, functional role, and clinical implications are still poorly known. METHODS PCa specimens (n = 52) from biopsies and control prostates from cystoprostatectomies (n = 12), as well as in silico databases were used to evaluate SSTR1 and miRNAs expression. In vitro studies in 22Rv1 PCa cells were implemented to explore the regulation of SSTR1/sst1 by different miRNAs, and to evaluate the consequences of SSTR1/sst1 overexpression, silencing and/or activation [with the specific BIM-23926 sst1 agonist (IPSEN)] on cell-proliferation, migration, signaling-pathways, and androgen-signaling. RESULTS We found that SSTR1 is overexpressed in multiple cohorts of PCa samples, as compared with normal prostate tissues, wherein it correlates with androgen receptor (AR) expression, and appears to be associated with aggressiveness (metastasis). Furthermore, our data revealed that SSTR1/sst1 expression might be regulated by specific miRNAs in PCa, including miR-24, which is downregulated in PCa samples and correlates inversely with SSTR1 expression. In vitro studies indicated that treatment with the BIM-23926 sst1 agonist, as well as SSTR1 overexpression, decreased, whereas SSTR1 silencing increased, cell-proliferation in 22Rv1 cells, likely through the regulation of PI3K/AKT-CCND3 signaling-pathway. Importantly, sst1 action was also able to modulate androgen/AR activity, and reduced PSA secretion from PCa cell lines. CONCLUSIONS Altogether, our results indicate that SSTR1 is overexpressed in PCa, where it can exert a relevant pathophysiological role by decreasing cell-proliferation and PSA secretion. Therefore, sst1, possibly in combination with miR-24, could be used as a novel tool to explore therapeutic targets in PCa.
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MESH Headings
- Aged
- Aged, 80 and over
- Biomarkers, Tumor/biosynthesis
- Biomarkers, Tumor/genetics
- Cell Line, Tumor
- Humans
- Male
- Middle Aged
- Molecular Targeted Therapy
- Prostatic Neoplasms, Castration-Resistant/diagnosis
- Prostatic Neoplasms, Castration-Resistant/genetics
- Prostatic Neoplasms, Castration-Resistant/metabolism
- Prostatic Neoplasms, Castration-Resistant/therapy
- Receptors, Somatostatin/biosynthesis
- Receptors, Somatostatin/genetics
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Affiliation(s)
- Sergio Pedraza-Arévalo
- Maimonides Institute for Biomedical Research of Cordoba (IMIBIC), Córdoba, Spain
- Department of Cell Biology, Physiology, and Immunology, Universidad de Córdoba, Córdoba, Spain
- Reina Sofia University Hospital, Córdoba, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn), Córdoba, Spain
| | - Daniel Hormaechea-Agulla
- Maimonides Institute for Biomedical Research of Cordoba (IMIBIC), Córdoba, Spain
- Department of Cell Biology, Physiology, and Immunology, Universidad de Córdoba, Córdoba, Spain
- Reina Sofia University Hospital, Córdoba, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn), Córdoba, Spain
| | - Enrique Gómez-Gómez
- Maimonides Institute for Biomedical Research of Cordoba (IMIBIC), Córdoba, Spain
- Department of Cell Biology, Physiology, and Immunology, Universidad de Córdoba, Córdoba, Spain
- Reina Sofia University Hospital, Córdoba, Spain
- Urology Service, Reina Sofia University Hospital, Córdoba, Spain
| | - María J Requena
- Maimonides Institute for Biomedical Research of Cordoba (IMIBIC), Córdoba, Spain
- Department of Cell Biology, Physiology, and Immunology, Universidad de Córdoba, Córdoba, Spain
- Reina Sofia University Hospital, Córdoba, Spain
- Urology Service, Reina Sofia University Hospital, Córdoba, Spain
| | - Luke A Selth
- Dame Roma Mitchell Cancer Research Laboratories and Freemasons Foundation Centre for Men's Health, Adelaide Medical School, The University of Adelaide, SA, 5005, Australia
| | - Manuel D Gahete
- Maimonides Institute for Biomedical Research of Cordoba (IMIBIC), Córdoba, Spain
- Department of Cell Biology, Physiology, and Immunology, Universidad de Córdoba, Córdoba, Spain
- Reina Sofia University Hospital, Córdoba, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn), Córdoba, Spain
| | - Justo P Castaño
- Maimonides Institute for Biomedical Research of Cordoba (IMIBIC), Córdoba, Spain
- Department of Cell Biology, Physiology, and Immunology, Universidad de Córdoba, Córdoba, Spain
- Reina Sofia University Hospital, Córdoba, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn), Córdoba, Spain
| | - Raul M Luque
- Maimonides Institute for Biomedical Research of Cordoba (IMIBIC), Córdoba, Spain
- Department of Cell Biology, Physiology, and Immunology, Universidad de Córdoba, Córdoba, Spain
- Reina Sofia University Hospital, Córdoba, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn), Córdoba, Spain
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Lau A, Bourkas M, Lu YQQ, Ostrowski LA, Weber-Adrian D, Figueiredo C, Arshad H, Shoaei SZS, Morrone CD, Matan-Lithwick S, Abraham KJ, Wang H, Schmitt-Ulms G. Functional Amyloids and their Possible Influence on Alzheimer Disease. Discoveries (Craiova) 2017; 5:e79. [PMID: 32309597 PMCID: PMC7159844 DOI: 10.15190/d.2017.9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Amyloids play critical roles in human diseases but have increasingly been recognized to also exist naturally. Shared physicochemical characteristics of amyloids and of their smaller oligomeric building blocks offer the prospect of molecular interactions and crosstalk amongst these assemblies, including the propensity to mutually influence aggregation. A case in point might be the recent discovery of an interaction between the amyloid β peptide (Aβ) and somatostatin (SST). Whereas Aβ is best known for its role in Alzheimer disease (AD) as the main constituent of amyloid plaques, SST is intermittently stored in amyloid-form in dense core granules before its regulated release into the synaptic cleft. This review was written to introduce to readers a large body of literature that surrounds these two peptides. After introducing general concepts and recent progress related to our understanding of amyloids and their aggregation, the review focuses separately on the biogenesis and interactions of Aβ and SST, before attempting to assess the likelihood of encounters of the two peptides in the brain, and summarizing key observations linking SST to the pathobiology of AD. While the review focuses on Aβ and SST, it is to be anticipated that crosstalk amongst functional and disease-associated amyloids will emerge as a general theme with much broader significance in the etiology of dementias and other amyloidosis.
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Affiliation(s)
- Angus Lau
- Department of Laboratory Medicine & Pathobiology, University of Toronto, Medical Sciences Building, 6th Floor, 1 King's College Circle, Toronto, Ontario M5S 1A8, Canada.,Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Krembil Discovery Centre, 6th Floor, 60 Leonard Avenue, Toronto, Ontario M5T 2S8, Canada
| | - Matthew Bourkas
- Department of Laboratory Medicine & Pathobiology, University of Toronto, Medical Sciences Building, 6th Floor, 1 King's College Circle, Toronto, Ontario M5S 1A8, Canada.,Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Krembil Discovery Centre, 6th Floor, 60 Leonard Avenue, Toronto, Ontario M5T 2S8, Canada
| | - Yang Qing Qin Lu
- Department of Laboratory Medicine & Pathobiology, University of Toronto, Medical Sciences Building, 6th Floor, 1 King's College Circle, Toronto, Ontario M5S 1A8, Canada
| | - Lauren Anne Ostrowski
- Department of Laboratory Medicine & Pathobiology, University of Toronto, Medical Sciences Building, 6th Floor, 1 King's College Circle, Toronto, Ontario M5S 1A8, Canada
| | - Danielle Weber-Adrian
- Department of Laboratory Medicine & Pathobiology, University of Toronto, Medical Sciences Building, 6th Floor, 1 King's College Circle, Toronto, Ontario M5S 1A8, Canada
| | - Carlyn Figueiredo
- Department of Laboratory Medicine & Pathobiology, University of Toronto, Medical Sciences Building, 6th Floor, 1 King's College Circle, Toronto, Ontario M5S 1A8, Canada
| | - Hamza Arshad
- Department of Laboratory Medicine & Pathobiology, University of Toronto, Medical Sciences Building, 6th Floor, 1 King's College Circle, Toronto, Ontario M5S 1A8, Canada.,Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Krembil Discovery Centre, 6th Floor, 60 Leonard Avenue, Toronto, Ontario M5T 2S8, Canada
| | - Seyedeh Zahra Shams Shoaei
- Department of Laboratory Medicine & Pathobiology, University of Toronto, Medical Sciences Building, 6th Floor, 1 King's College Circle, Toronto, Ontario M5S 1A8, Canada
| | - Christopher Daniel Morrone
- Department of Laboratory Medicine & Pathobiology, University of Toronto, Medical Sciences Building, 6th Floor, 1 King's College Circle, Toronto, Ontario M5S 1A8, Canada
| | - Stuart Matan-Lithwick
- Department of Laboratory Medicine & Pathobiology, University of Toronto, Medical Sciences Building, 6th Floor, 1 King's College Circle, Toronto, Ontario M5S 1A8, Canada
| | - Karan Joshua Abraham
- Department of Laboratory Medicine & Pathobiology, University of Toronto, Medical Sciences Building, 6th Floor, 1 King's College Circle, Toronto, Ontario M5S 1A8, Canada
| | - Hansen Wang
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Krembil Discovery Centre, 6th Floor, 60 Leonard Avenue, Toronto, Ontario M5T 2S8, Canada
| | - Gerold Schmitt-Ulms
- Department of Laboratory Medicine & Pathobiology, University of Toronto, Medical Sciences Building, 6th Floor, 1 King's College Circle, Toronto, Ontario M5S 1A8, Canada.,Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Krembil Discovery Centre, 6th Floor, 60 Leonard Avenue, Toronto, Ontario M5T 2S8, Canada
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44
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Fee C, Banasr M, Sibille E. Somatostatin-Positive Gamma-Aminobutyric Acid Interneuron Deficits in Depression: Cortical Microcircuit and Therapeutic Perspectives. Biol Psychiatry 2017; 82:549-559. [PMID: 28697889 PMCID: PMC5610074 DOI: 10.1016/j.biopsych.2017.05.024] [Citation(s) in RCA: 188] [Impact Index Per Article: 26.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Revised: 05/11/2017] [Accepted: 05/30/2017] [Indexed: 12/17/2022]
Abstract
The functional integration of external and internal signals forms the basis of information processing and is essential for higher cognitive functions. This occurs in finely tuned cortical microcircuits whose functions are balanced at the cellular level by excitatory glutamatergic pyramidal neurons and inhibitory gamma-aminobutyric acidergic (GABAergic) interneurons. The balance of excitation and inhibition, from cellular processes to neural network activity, is characteristically disrupted in multiple neuropsychiatric disorders, including major depressive disorder (MDD), bipolar disorder, anxiety disorders, and schizophrenia. Specifically, nearly 3 decades of research demonstrate a role for reduced inhibitory GABA level and function across disorders. In MDD, recent evidence from human postmortem and animal studies suggests a selective vulnerability of GABAergic interneurons that coexpress the neuropeptide somatostatin (SST). Advances in cell type-specific molecular genetics have now helped to elucidate several important roles for SST interneurons in cortical processing (regulation of pyramidal cell excitatory input) and behavioral control (mood and cognition). Here, we review evidence for altered inhibitory function arising from GABAergic deficits across disorders and specifically in MDD. We then focus on properties of the cortical microcircuit, where SST-positive GABAergic interneuron deficits may disrupt functioning in several ways. Finally, we discuss the putative origins of SST cell deficits, as informed by recent research, and implications for therapeutic approaches. We conclude that deficits in SST interneurons represent a contributing cellular pathology and therefore a promising target for normalizing altered inhibitory function in MDD and other disorders with reduced SST cell and GABA functions.
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Affiliation(s)
- Corey Fee
- Campbell Family Mental Health Research Institute of Centre for Addiction and Mental Health, Toronto, Ontario, Canada; Department of Pharmacology and Toxicology, University of Toronto, Toronto, Ontario, Canada
| | - Mounira Banasr
- Campbell Family Mental Health Research Institute of Centre for Addiction and Mental Health, Toronto, Ontario, Canada; Department of Pharmacology and Toxicology, University of Toronto, Toronto, Ontario, Canada
| | - Etienne Sibille
- Campbell Family Mental Health Research Institute of Centre for Addiction and Mental Health, Toronto, Ontario, Canada; Department of Pharmacology and Toxicology, University of Toronto, Toronto, Ontario, Canada; Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada.
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45
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Hu B, Cilz NI, Lei S. Somatostatin depresses the excitability of subicular bursting cells: Roles of inward rectifier K + channels, KCNQ channels and Epac. Hippocampus 2017; 27:971-984. [PMID: 28558129 DOI: 10.1002/hipo.22744] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2017] [Revised: 05/08/2017] [Accepted: 05/18/2017] [Indexed: 12/17/2022]
Abstract
The hippocampus is a crucial component for cognitive and emotional processing. The subiculum provides much of the output for this structure but the modulation and function of this region is surprisingly under-studied. The neuromodulator somatostatin (SST) interacts with five subtypes of SST receptors (sst1 to sst5 ) and each of these SST receptor subtypes is coupled to Gi proteins resulting in inhibition of adenylyl cyclase (AC) and decreased level of intracellular cAMP. SST modulates many physiological functions including cognition, emotion, autonomic responses and locomotion. Whereas SST has been shown to depress neuronal excitability in the subiculum, the underlying cellular and molecular mechanisms have not yet been determined. Here, we show that SST hyperpolarized two classes of subicular neurons with a calculated EC50 of 0.1 μM. Application of SST (1 μM) induced outward holding currents by primarily activating K+ channels including the G-protein-activated inwardly-rectifying potassium channels (GIRK) and KCNQ (M) channels, although inhibition of cation channels in some cells may also be implicated. SST-elicited hyperpolarization was mediated by activation of sst2 receptors and required the function of G proteins. The SST-induced hyperpolarization resulted from decreased activity of AC and reduced levels of cAMP but did not require the activity of either PKA or PKC. Inhibition of Epac2, a guanine nucleotide exchange factor, partially blocked SST-mediated hyperpolarization of subicular neurons. Furthermore, application of SST resulted in a robust depression of subicular action potential firing and the SST-induced hyperpolarization was responsible for its inhibitory action on LTP at the CA1-subicilum synapses. Our results provide a novel cellular and molecular mechanism that may explain the roles of SST in modulation of subicular function and be relevant to SST-related physiological functions.
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Affiliation(s)
- Binqi Hu
- Department of Biomedical Sciences, School of Medicine and Health Sciences, University of North Dakota, Grand Forks, North Dakota 58203
| | - Nicholas I Cilz
- Department of Biomedical Sciences, School of Medicine and Health Sciences, University of North Dakota, Grand Forks, North Dakota 58203
| | - Saobo Lei
- Department of Biomedical Sciences, School of Medicine and Health Sciences, University of North Dakota, Grand Forks, North Dakota 58203
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46
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French L, Ma T, Oh H, Tseng GC, Sibille E. Age-Related Gene Expression in the Frontal Cortex Suggests Synaptic Function Changes in Specific Inhibitory Neuron Subtypes. Front Aging Neurosci 2017; 9:162. [PMID: 28611654 PMCID: PMC5446995 DOI: 10.3389/fnagi.2017.00162] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Accepted: 05/09/2017] [Indexed: 12/22/2022] Open
Abstract
Genome-wide expression profiling of the human brain has revealed genes that are differentially expressed across the lifespan. Characterizing these genes adds to our understanding of both normal functions and pathological conditions. Additionally, the specific cell-types that contribute to the motor, sensory and cognitive declines during aging are unclear. Here we test if age-related genes show higher expression in specific neural cell types. Our study leverages data from two sources of murine single-cell expression data and two sources of age-associations from large gene expression studies of postmortem human brain. We used nonparametric gene set analysis to test for age-related enrichment of genes associated with specific cell-types; we also restricted our analyses to specific gene ontology groups. Our analyses focused on a primary pair of single-cell expression data from the mouse visual cortex and age-related human post-mortem gene expression information from the orbitofrontal cortex. Additional pairings that used data from the hippocampus, prefrontal cortex, somatosensory cortex and blood were used to validate and test specificity of our findings. We found robust age-related up-regulation of genes that are highly expressed in oligodendrocytes and astrocytes, while genes highly expressed in layer 2/3 glutamatergic neurons were down-regulated across age. Genes not specific to any neural cell type were also down-regulated, possibly due to the bulk tissue source of the age-related genes. A gene ontology-driven dissection of the cell-type enriched genes highlighted the strong down-regulation of genes involved in synaptic transmission and cell-cell signaling in the Somatostatin (Sst) neuron subtype that expresses the cyclin dependent kinase 6 (Cdk6) and in the vasoactive intestinal peptide (Vip) neuron subtype expressing myosin binding protein C, slow type (Mybpc1). These findings provide new insights into cell specific susceptibility to normal aging, and suggest age-related synaptic changes in specific inhibitory neuron subtypes.
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Affiliation(s)
- Leon French
- Neurobiology of Depression and Aging Lab, Centre for Addiction and Mental Health, Campbell Family Mental Health Research InstituteToronto, ON, Canada.,Department of Psychiatry, University of TorontoToronto, ON, Canada.,Institute of Medical Science, University of TorontoToronto, ON, Canada
| | - TianZhou Ma
- Department of Biostatistics, University of PittsburghPittsburgh, PA, United States
| | - Hyunjung Oh
- Neurobiology of Depression and Aging Lab, Centre for Addiction and Mental Health, Campbell Family Mental Health Research InstituteToronto, ON, Canada
| | - George C Tseng
- Department of Biostatistics, University of PittsburghPittsburgh, PA, United States
| | - Etienne Sibille
- Neurobiology of Depression and Aging Lab, Centre for Addiction and Mental Health, Campbell Family Mental Health Research InstituteToronto, ON, Canada.,Department of Psychiatry, University of TorontoToronto, ON, Canada.,Department of Pharmacology and Toxicology, University of TorontoToronto, ON, Canada
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47
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Scheich B, Csekő K, Borbély É, Ábrahám I, Csernus V, Gaszner B, Helyes Z. Higher susceptibility of somatostatin 4 receptor gene-deleted mice to chronic stress-induced behavioral and neuroendocrine alterations. Neuroscience 2017; 346:320-336. [DOI: 10.1016/j.neuroscience.2017.01.039] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2016] [Revised: 01/17/2017] [Accepted: 01/24/2017] [Indexed: 01/20/2023]
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48
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Viollet C, Simon A, Tolle V, Labarthe A, Grouselle D, Loe-Mie Y, Simonneau M, Martel G, Epelbaum J. Somatostatin-IRES-Cre Mice: Between Knockout and Wild-Type? Front Endocrinol (Lausanne) 2017; 8:131. [PMID: 28674519 PMCID: PMC5474965 DOI: 10.3389/fendo.2017.00131] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Accepted: 05/29/2017] [Indexed: 01/24/2023] Open
Abstract
The neuropeptide somatostatin (SOM) is widely expressed in rodent brain and somatostatin-IRES-Cre (SOM-cre) mouse strains are increasingly used to unravel the physiology of SOM-containing neurons. However, while knock-in targeting strategy greatly improves Cre-Lox system accuracy, recent reports have shown that genomic insertion of Cre construct per se can markedly affect physiological function. We show that Cre transgene insertion into the 3'UTR of the somatostatin gene leads to the selective and massive depletion of endogenous SOM in all tested brain regions. It also strongly impacts SOM-related neuroendocrine responses in a similar manner to what has been reported for SST KO mice: increased corticosterone levels after 30-min restraint stress, decreased amplitude and regularity of ultradian growth hormone secretory patterns accompanied by changes in sexually dimorphic liver gene expression (serpina1, Cyp2b9, Cyp2a4, Cyp2d9, and Cyp7b1). In addition to demonstrating the need for examination of the consequences of Cre transgenesis, these results also reveal how this SOM-cre strain may be a useful tool in studying the functional consequences of moderate to low SOM levels as reported in neurological and psychiatric disorders.
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Affiliation(s)
- Cécile Viollet
- INSERM U894, Centre de Psychiatrie et Neurosciences, Université Paris-Descartes, Sorbonne Paris-Cité, Paris, France
- *Correspondence: Cécile Viollet, ; Jacques Epelbaum,
| | - Axelle Simon
- INSERM U894, Centre de Psychiatrie et Neurosciences, Université Paris-Descartes, Sorbonne Paris-Cité, Paris, France
| | - Virginie Tolle
- INSERM U894, Centre de Psychiatrie et Neurosciences, Université Paris-Descartes, Sorbonne Paris-Cité, Paris, France
| | - Alexandra Labarthe
- INSERM U894, Centre de Psychiatrie et Neurosciences, Université Paris-Descartes, Sorbonne Paris-Cité, Paris, France
| | - Dominique Grouselle
- INSERM U894, Centre de Psychiatrie et Neurosciences, Université Paris-Descartes, Sorbonne Paris-Cité, Paris, France
| | - Yann Loe-Mie
- INSERM U894, Centre de Psychiatrie et Neurosciences, Université Paris-Descartes, Sorbonne Paris-Cité, Paris, France
| | - Michel Simonneau
- INSERM U894, Centre de Psychiatrie et Neurosciences, Université Paris-Descartes, Sorbonne Paris-Cité, Paris, France
- Laboratoire Aimé Cotton, CNRS, Université Paris-Sud, ENS Paris-Saclay, Université Paris-Saclay, Orsay, France
| | - Guillaume Martel
- INSERM U894, Centre de Psychiatrie et Neurosciences, Université Paris-Descartes, Sorbonne Paris-Cité, Paris, France
| | - Jacques Epelbaum
- INSERM U894, Centre de Psychiatrie et Neurosciences, Université Paris-Descartes, Sorbonne Paris-Cité, Paris, France
- MECADEV UMR 7179 CNRS, Muséum National d’Histoire Naturelle, Brunoy, France
- *Correspondence: Cécile Viollet, ; Jacques Epelbaum,
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49
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Llona I, Farías P, Troc-Gajardo JL. Early Postnatal Development of Somastostatinergic Systems in Brainstem Respiratory Network. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 1015:131-144. [DOI: 10.1007/978-3-319-62817-2_8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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50
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Pacheco-Quinto J, Eckman CB, Eckman EA. Major amyloid-β-degrading enzymes, endothelin-converting enzyme-2 and neprilysin, are expressed by distinct populations of GABAergic interneurons in hippocampus and neocortex. Neurobiol Aging 2016; 48:83-92. [PMID: 27644077 DOI: 10.1016/j.neurobiolaging.2016.08.011] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2016] [Revised: 08/10/2016] [Accepted: 08/12/2016] [Indexed: 01/17/2023]
Abstract
Impaired clearance of amyloid-β peptide (Aβ) has been postulated to significantly contribute to the amyloid accumulation typical of Alzheimer's disease. Among the enzymes known to degrade Aβ in vivo are endothelin-converting enzyme (ECE)-1, ECE-2, and neprilysin (NEP), and evidence suggests that they regulate independent pools of Aβ that may be functionally significant. To better understand the differential regulation of Aβ concentration by its physiological degrading enzymes, we characterized the cell and region-specific expression pattern of ECE-1, ECE-2, and NEP by in situ hybridization and immunohistochemistry in brain areas relevant to Alzheimer's disease. In contrast to the broader distribution of ECE-1, ECE-2 and NEP were found enriched in GABAergic neurons. ECE-2 was majorly expressed by somatostatin-expressing interneurons and was active in isolated synaptosomes. NEP messenger RNA was found mainly in parvalbumin-expressing interneurons, with NEP protein localized to perisomatic parvalbuminergic synapses. The identification of somatostatinergic and parvalbuminergic synapses as hubs for Aβ degradation is consistent with the possibility that Aβ may have a physiological function related to the regulation of inhibitory signaling.
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Affiliation(s)
- Javier Pacheco-Quinto
- Atlantic Health System, Morristown, NJ, USA; Biomedical Research Institute of New Jersey, Cedar Knolls, NJ, USA
| | - Christopher B Eckman
- Atlantic Health System, Morristown, NJ, USA; Biomedical Research Institute of New Jersey, Cedar Knolls, NJ, USA
| | - Elizabeth A Eckman
- Atlantic Health System, Morristown, NJ, USA; Biomedical Research Institute of New Jersey, Cedar Knolls, NJ, USA.
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