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Remex NS, Abdullah CS, Aishwarya R, Kolluru GK, Traylor J, Bhuiyan MAN, Kevil CG, Orr AW, Rom O, Pattillo CB, Bhuiyan MS. Deletion of Sigmar1 leads to increased arterial stiffness and altered mitochondrial respiration resulting in vascular dysfunction. Front Physiol 2024; 15:1386296. [PMID: 38742156 PMCID: PMC11089145 DOI: 10.3389/fphys.2024.1386296] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2024] [Accepted: 04/15/2024] [Indexed: 05/16/2024] Open
Abstract
Sigmar1 is a ubiquitously expressed, multifunctional protein known for its cardioprotective roles in cardiovascular diseases. While accumulating evidence indicate a critical role of Sigmar1 in cardiac biology, its physiological function in the vasculature remains unknown. In this study, we characterized the expression of Sigmar1 in the vascular wall and assessed its physiological function in the vascular system using global Sigmar1 knockout (Sigmar1-/-) mice. We determined the expression of Sigmar1 in the vascular tissue using immunostaining and biochemical experiments in both human and mouse blood vessels. Deletion of Sigmar1 globally in mice (Sigmar1-/-) led to blood vessel wall reorganizations characterized by nuclei disarray of vascular smooth muscle cells, altered organizations of elastic lamina, and higher collagen fibers deposition in and around the arteries compared to wildtype littermate controls (Wt). Vascular function was assessed in mice using non-invasive time-transit method of aortic stiffness measurement and flow-mediated dilation (FMD) of the left femoral artery. Sigmar1-/- mice showed a notable increase in arterial stiffness in the abdominal aorta and failed to increase the vessel diameter in response to reactive-hyperemia compared to Wt. This was consistent with reduced plasma and tissue nitric-oxide bioavailability (NOx) and decreased phosphorylation of endothelial nitric oxide synthase (eNOS) in the aorta of Sigmar1-/- mice. Ultrastructural analysis by transmission electron microscopy (TEM) of aorta sections showed accumulation of elongated shaped mitochondria in both vascular smooth muscle and endothelial cells of Sigmar1-/- mice. In accordance, decreased mitochondrial respirometry parameters were found in ex-vivo aortic rings from Sigmar1 deficient mice compared to Wt controls. These data indicate a potential role of Sigmar1 in maintaining vascular homeostasis.
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Affiliation(s)
- Naznin Sultana Remex
- Department of Molecular and Cellular Physiology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA, United States
| | - Chowdhury S. Abdullah
- Department of Pathology and Translational Pathobiology, Louisiana State University Health, Shreveport, LA, United States
| | - Richa Aishwarya
- Department of Pathology and Translational Pathobiology, Louisiana State University Health, Shreveport, LA, United States
| | - Gopi K. Kolluru
- Department of Pathology and Translational Pathobiology, Louisiana State University Health, Shreveport, LA, United States
| | - James Traylor
- Department of Pathology and Translational Pathobiology, Louisiana State University Health, Shreveport, LA, United States
| | - Mohammad Alfrad Nobel Bhuiyan
- Department of Internal Medicine, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA, United States
| | - Christopher G. Kevil
- Department of Molecular and Cellular Physiology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA, United States
- Department of Pathology and Translational Pathobiology, Louisiana State University Health, Shreveport, LA, United States
| | - A. Wayne Orr
- Department of Molecular and Cellular Physiology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA, United States
- Department of Pathology and Translational Pathobiology, Louisiana State University Health, Shreveport, LA, United States
| | - Oren Rom
- Department of Molecular and Cellular Physiology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA, United States
- Department of Pathology and Translational Pathobiology, Louisiana State University Health, Shreveport, LA, United States
| | - Christopher B. Pattillo
- Department of Molecular and Cellular Physiology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA, United States
| | - Md. Shenuarin Bhuiyan
- Department of Molecular and Cellular Physiology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA, United States
- Department of Pathology and Translational Pathobiology, Louisiana State University Health, Shreveport, LA, United States
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2
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Nguyen NT, Jaramillo-Martinez V, Mathew M, Suresh VV, Sivaprakasam S, Bhutia YD, Ganapathy V. Sigma Receptors: Novel Regulators of Iron/Heme Homeostasis and Ferroptosis. Int J Mol Sci 2023; 24:14672. [PMID: 37834119 PMCID: PMC10572259 DOI: 10.3390/ijms241914672] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Revised: 09/13/2023] [Accepted: 09/20/2023] [Indexed: 10/15/2023] Open
Abstract
Sigma receptors are non-opiate/non-phencyclidine receptors that bind progesterone and/or heme and also several unrelated xenobiotics/chemicals. They reside in the plasma membrane and in the membranes of the endoplasmic reticulum, mitochondria, and nucleus. Until recently, the biology/pharmacology of these proteins focused primarily on their role in neuronal functions in the brain/retina. However, there have been recent developments in the field with the discovery of unexpected roles for these proteins in iron/heme homeostasis. Sigma receptor 1 (S1R) regulates the oxidative stress-related transcription factor NRF2 and protects against ferroptosis, an iron-induced cell death process. Sigma receptor 2 (S2R), which is structurally unrelated to S1R, complexes with progesterone receptor membrane components PGRMC1 and PGRMC2. S2R, PGRMC1, and PGRMC2, either independently or as protein-protein complexes, elicit a multitude of effects with a profound influence on iron/heme homeostasis. This includes the regulation of the secretion of the iron-regulatory hormone hepcidin, the modulation of the activity of mitochondrial ferrochelatase, which catalyzes iron incorporation into protoporphyrin IX to form heme, chaperoning heme to specific hemoproteins thereby influencing their biological activity and stability, and protection against ferroptosis. Consequently, S1R, S2R, PGRMC1, and PGRMC2 potentiate disease progression in hemochromatosis and cancer. These new discoveries usher this intriguing group of non-traditional progesterone receptors into an unchartered territory in biology and medicine.
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Affiliation(s)
| | | | | | | | | | | | - Vadivel Ganapathy
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA; (N.T.N.); (V.J.-M.); (M.M.); (V.V.S.); (S.S.); (Y.D.B.)
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3
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Wang T, Jia H. The Sigma Receptors in Alzheimer's Disease: New Potential Targets for Diagnosis and Therapy. Int J Mol Sci 2023; 24:12025. [PMID: 37569401 PMCID: PMC10418732 DOI: 10.3390/ijms241512025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Revised: 07/14/2023] [Accepted: 07/16/2023] [Indexed: 08/13/2023] Open
Abstract
Sigma (σ) receptors are a class of unique proteins with two subtypes: the sigma-1 (σ1) receptor which is situated at the mitochondria-associated endoplasmic reticulum (ER) membrane (MAM), and the sigma-2 (σ2) receptor, located in the ER-resident membrane. Increasing evidence indicates the involvement of both σ1 and σ2 receptors in the pathogenesis of Alzheimer's disease (AD), and thus these receptors represent two potentially effective biomarkers for emerging AD therapies. The availability of optimal radioligands for positron emission tomography (PET) neuroimaging of the σ1 and σ2 receptors in humans will provide tools to monitor AD progression and treatment outcomes. In this review, we first summarize the significance of both receptors in the pathophysiology of AD and highlight AD therapeutic strategies related to the σ1 and σ2 receptors. We then survey the potential PET radioligands, with an emphasis on the requirements of optimal radioligands for imaging the σ1 or σ2 receptors in humans. Finally, we discuss current challenges in the development of PET radioligands for the σ1 or σ2 receptors, and the opportunities for neuroimaging to elucidate the σ1 and σ2 receptors as novel biomarkers for early AD diagnosis, and for monitoring of disease progression and AD drug efficacy.
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Affiliation(s)
- Tao Wang
- Key Laboratory of Radiopharmaceuticals (Beijing Normal University), Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China;
- Department of Nuclear Medicine, Xinqiao Hospital, Army Medical University, Chongqing 400037, China
| | - Hongmei Jia
- Key Laboratory of Radiopharmaceuticals (Beijing Normal University), Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China;
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4
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Couly S, Yasui Y, Su TP. SIGMAR1 Confers Innate Resilience against Neurodegeneration. Int J Mol Sci 2023; 24:ijms24097767. [PMID: 37175473 PMCID: PMC10178636 DOI: 10.3390/ijms24097767] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Revised: 04/15/2023] [Accepted: 04/19/2023] [Indexed: 05/15/2023] Open
Abstract
The sigma-1 receptor (SIGMAR1) is one of a kind: a receptor chaperone protein. This 223 amino acid-long protein is enriched at the mitochondria-associated endoplasmic reticulum membrane (MAM), a specialized microdomain of the endoplasmic reticulum that is structurally and functionally connected to the mitochondria. As a receptor, SIGMAR1 binds a wide spectrum of ligands. Numerous molecules targeting SIGMAR1 are currently in pre-clinical or clinical development. Interestingly, the range of pathologies covered by these studies is broad, especially with regard to neurodegenerative disorders. Upon activation, SIGMAR1 can translocate and interact with other proteins, mostly at the MAM but also in other organelles, which allows SIGMAR1 to affect many cellular functions. During these interactions, SIGMAR1 exhibits chaperone protein behavior by participating in the folding and stabilization of its partner. In this short communication, we will shed light on how SIGMAR1 confers protection against neurodegeneration to the cells of the nervous system and why this ability makes SIGMAR1 a multifunctional therapeutic prospect.
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Affiliation(s)
- Simon Couly
- Cellular Pathobiology Section, Integrative Neuroscience Research Branch, Intramural Research Program, National Institute on Drug Abuse, NIH, 333 Cassell Drive, Baltimore, MD 21224, USA
| | - Yuko Yasui
- Cellular Pathobiology Section, Integrative Neuroscience Research Branch, Intramural Research Program, National Institute on Drug Abuse, NIH, 333 Cassell Drive, Baltimore, MD 21224, USA
| | - Tsung-Ping Su
- Cellular Pathobiology Section, Integrative Neuroscience Research Branch, Intramural Research Program, National Institute on Drug Abuse, NIH, 333 Cassell Drive, Baltimore, MD 21224, USA
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Remex NS, Abdullah CS, Aishwarya R, Nitu SS, Traylor J, Hartman B, King J, Bhuiyan MAN, Kevil CG, Orr AW, Bhuiyan MS. Sigmar1 ablation leads to lung pathological changes associated with pulmonary fibrosis, inflammation, and altered surfactant proteins levels. Front Physiol 2023; 14:1118770. [PMID: 37051024 PMCID: PMC10083329 DOI: 10.3389/fphys.2023.1118770] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Accepted: 03/14/2023] [Indexed: 03/28/2023] Open
Abstract
Sigma1 receptor protein (Sigmar1) is a small, multifunctional molecular chaperone protein ubiquitously expressed in almost all body tissues. This protein has previously shown its cardioprotective roles in rodent models of cardiac hypertrophy, heart failure, and ischemia-reperfusion injury. Extensive literature also suggested its protective functions in several central nervous system disorders. Sigmar1's molecular functions in the pulmonary system remained unknown. Therefore, we aimed to determine the expression of Sigmar1 in the lungs. We also examined whether Sigmar1 ablation results in histological, ultrastructural, and biochemical changes associated with lung pathology over aging in mice. In the current study, we first confirmed the presence of Sigmar1 protein in human and mouse lungs using immunohistochemistry and immunostaining. We used the Sigmar1 global knockout mouse (Sigmar1-/-) to determine the pathophysiological role of Sigmar1 in lungs over aging. The histological staining of lung sections showed altered alveolar structures, higher immune cells infiltration, and upregulation of inflammatory markers (such as pNFκB) in Sigmar1-/- mice compared to wildtype (Wt) littermate control mice (Wt). This indicates higher pulmonary inflammation resulting from Sigmar1 deficiency in mice, which was associated with increased pulmonary fibrosis. The protein levels of some fibrotic markers, fibronectin, and pSMAD2 Ser 245/250/255 and Ser 465/467, were also elevated in mice lungs in the absence of Sigmar1 compared to Wt. The ultrastructural analysis of lungs in Wt mice showed numerous multilamellar bodies of different sizes with densely packed lipid lamellae and mitochondria with a dark matrix and dense cristae. In contrast, the Sigmar1-/- mice lung tissues showed altered multilamellar body structures in alveolar epithelial type-II pneumocytes with partial loss of lipid lamellae structures in the lamellar bodies. This was further associated with higher protein levels of all four surfactant proteins, SFTP-A, SFTP-B, SFTP-C, and SFTP-D, in the Sigmar1-/- mice lungs. This is the first study showing Sigmar1's expression pattern in human and mouse lungs and its association with lung pathophysiology. Our findings suggest that Sigmar1 deficiency leads to increased pulmonary inflammation, higher pulmonary fibrosis, alterations of the multilamellar body stuructures, and elevated levels of lung surfactant proteins.
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Affiliation(s)
- Naznin Sultana Remex
- Department of Molecular and Cellular Physiology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA, United States
| | - Chowdhury S. Abdullah
- Department of Pathology and Translational Pathobiology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA, United States
| | - Richa Aishwarya
- Department of Pathology and Translational Pathobiology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA, United States
| | - Sadia S. Nitu
- Department of Pathology and Translational Pathobiology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA, United States
| | - James Traylor
- Department of Pathology and Translational Pathobiology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA, United States
| | - Brandon Hartman
- Department of Pathology and Translational Pathobiology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA, United States
| | - Judy King
- Department of Pathology and Translational Pathobiology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA, United States
| | - Mohammad Alfrad Nobel Bhuiyan
- Department of Internal Medicine, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA, United States
| | - Christopher G. Kevil
- Department of Molecular and Cellular Physiology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA, United States
- Department of Pathology and Translational Pathobiology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA, United States
| | - A. Wayne Orr
- Department of Molecular and Cellular Physiology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA, United States
- Department of Pathology and Translational Pathobiology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA, United States
| | - Md. Shenuarin Bhuiyan
- Department of Molecular and Cellular Physiology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA, United States
- Department of Pathology and Translational Pathobiology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA, United States
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Weng CC, Riad A, Lieberman BP, Xu K, Peng X, Mikitsh JL, Mach RH. Characterization of Sigma-2 Receptor-Specific Binding Sites Using [ 3H]DTG and [ 125I]RHM-4. Pharmaceuticals (Basel) 2022; 15:ph15121564. [PMID: 36559015 PMCID: PMC9784403 DOI: 10.3390/ph15121564] [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: 11/07/2022] [Revised: 11/30/2022] [Accepted: 12/12/2022] [Indexed: 12/23/2022] Open
Abstract
The sigma-2 receptor/transmembrane protein 97 (σ2R/TMRM97) is a promising biomarker of tumor proliferation and a target for cancer therapy. [3H]DTG has been used to evaluate σ2R/TMEM97 binding affinity in compound development studies. However, [3H]DTG has equal and moderate binding affinities to both sigma 1 receptor (σ1R) and σ2R/TMEM97. Furthermore, co-administration with the σ1R masking compound (+)-pentazocine may cause bias in σ2R/TMEM97 binding affinity screening experiments. We have developed a radioiodinated ligand, [125I]RHM-4, which has high affinity and selectivity for σ2R/TMEM97 versus σ1R. In this study, a head-to-head comparison between [3H]DTG and [125I]RHM-4 on the binding affinity and their effectiveness in σ2R/TMEM97 compound screening studies was performed. The goal of these studies was to determine if this radioiodinated ligand is a suitable replacement for [3H]DTG for screening new σ2R/TMEM97 compounds. Furthermore, to delineate the binding properties of [125I]RHM-4 to the σ2R/TMEM97, the structure of RHM-4 was split into two fragments. This resulted in the identification of two binding regions in the σ2R, the "DTG" binding site, which is responsible for binding to the σ2R/TMEM97, and the secondary binding site, which is responsible for high affinity and selectivity for the σ2R/TMEM97 versus the σ1R. The results of this study indicate that [125I]RHM-4 is an improved radioligand for in vitro binding studies of the σ2R/TMEM97 versus [3H]DTG.
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Affiliation(s)
- Chi-Chang Weng
- HARC and Department of Medical Imaging and Radiological Sciences, Chang Gung University, Taoyuan 333, Taiwan
- Department of Nuclear Medicine and Center for Advanced Molecular Imaging and Translation, Linkou Chang Gung Memorial Hospital, Taoyuan 333, Taiwan
- Division of Nuclear Medicine and Clinical Molecular Imaging, Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Aladdin Riad
- Division of Nuclear Medicine and Clinical Molecular Imaging, Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Brian P. Lieberman
- Division of Nuclear Medicine and Clinical Molecular Imaging, Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Kuiying Xu
- Division of Nuclear Medicine and Clinical Molecular Imaging, Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Xin Peng
- Division of Nuclear Medicine and Clinical Molecular Imaging, Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - John L. Mikitsh
- Division of Nuclear Medicine and Clinical Molecular Imaging, Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Robert H. Mach
- Division of Nuclear Medicine and Clinical Molecular Imaging, Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Correspondence: ; Tel.: +1-215-746-8233
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7
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Wang YM, Xia CY, Jia HM, He J, Lian WW, Yan Y, Wang WP, Zhang WK, Xu JK. Sigma-1 receptor: A potential target for the development of antidepressants. Neurochem Int 2022; 159:105390. [PMID: 35810915 DOI: 10.1016/j.neuint.2022.105390] [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: 02/22/2022] [Revised: 06/10/2022] [Accepted: 07/05/2022] [Indexed: 10/17/2022]
Abstract
Though a great many of studies on the development of antidepressants for the therapy of major depression disorder (MDD) and the development of antidepressants have been carried out, there still lacks an efficient approach in clinical practice. The involvement of Sigma-1 receptor in the pathological process of MDD has been verified. In this review, recent research focusing on the role of Sigma-1 receptor in the etiology of MDD were summarized. Preclinical studies and clinical trials have found that stress induce the variation of Sigma-1 receptor in the blood, brain and heart. Dysfunction and absence of Sigma-1 receptor result in depressive-like behaviors in rodent animals. Agonists of Sigma-1 receptor show not only antidepressant-like activities but also therapeutical effects in complications of depression. The mechanisms underlying antidepressant-like effects of Sigma-1 receptor may include suppressing neuroinflammation, regulating neurotransmitters, ameliorating brain-derived neurotrophic factor and N-Methyl-D-Aspartate receptor, and alleviating the endoplasmic reticulum stress and mitochondria damage during stress. Therefore, Sigma-1 receptor represents a potential target for antidepressants development.
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Affiliation(s)
- Yu-Ming Wang
- School of Life Sciences & School of Chinese Medicine Sciences, Beijing University of Chinese Medicine, Beijing, 100029, PR China; Institute of Clinical Medical Sciences & Department of Pharmacy, China-Japan Friendship Hospital, Beijing, 100029, PR China
| | - Cong-Yuan Xia
- Institute of Clinical Medical Sciences & Department of Pharmacy, China-Japan Friendship Hospital, Beijing, 100029, PR China
| | - Hong-Mei Jia
- Key Laboratory of Radiopharmaceuticals (Beijing Normal University), Ministry of Education, College of Chemistry, Beijing Normal University, Beijing, PR China
| | - Jun He
- Institute of Clinical Medical Sciences & Department of Pharmacy, China-Japan Friendship Hospital, Beijing, 100029, PR China
| | - Wen-Wen Lian
- Institute of Clinical Medical Sciences & Department of Pharmacy, China-Japan Friendship Hospital, Beijing, 100029, PR China
| | - Yu Yan
- Institute of Clinical Medical Sciences & Department of Pharmacy, China-Japan Friendship Hospital, Beijing, 100029, PR China
| | - Wen-Ping Wang
- Institute of Clinical Medical Sciences & Department of Pharmacy, China-Japan Friendship Hospital, Beijing, 100029, PR China
| | - Wei-Ku Zhang
- Institute of Clinical Medical Sciences & Department of Pharmacy, China-Japan Friendship Hospital, Beijing, 100029, PR China.
| | - Jie-Kun Xu
- School of Life Sciences & School of Chinese Medicine Sciences, Beijing University of Chinese Medicine, Beijing, 100029, PR China.
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8
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Couly S, Goguadze N, Yasui Y, Kimura Y, Wang SM, Sharikadze N, Wu HE, Su TP. Knocking Out Sigma-1 Receptors Reveals Diverse Health Problems. Cell Mol Neurobiol 2022; 42:597-620. [PMID: 33095392 PMCID: PMC8062587 DOI: 10.1007/s10571-020-00983-3] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Accepted: 10/14/2020] [Indexed: 02/07/2023]
Abstract
Sigma-1 receptor (Sig-1R) is a protein present in several organs such as brain, lung, and heart. In a cell, Sig-1R is mainly located across the membranes of the endoplasmic reticulum and more specifically at the mitochondria-associated membranes. Despite numerous studies showing that Sig-1R could be targeted to rescue several cellular mechanisms in different pathological conditions, less is known about its fundamental relevance. In this review, we report results from various studies and focus on the importance of Sig-1R in physiological conditions by comparing Sig-1R KO mice to wild-type mice in order to investigate the fundamental functions of Sig-1R. We note that the Sig-1R deletion induces cognitive, psychiatric, and motor dysfunctions, but also alters metabolism of heart. Finally, taken together, observations from different experiments demonstrate that those dysfunctions are correlated to poor regulation of ER and mitochondria metabolism altered by stress, which could occur with aging.
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Affiliation(s)
- Simon Couly
- Cellular Pathobiology Section, Integrative Neuroscience Branch, Intramural Research Program, National Institute on Drug Abuse, DHHS, IRP, NIH, Triad Technology Center 333 Cassell Drive, Baltimore, MD, 21224 NIH, USA.
| | - Nino Goguadze
- Cellular Pathobiology Section, Integrative Neuroscience Branch, Intramural Research Program, National Institute on Drug Abuse, DHHS, IRP, NIH, Triad Technology Center 333 Cassell Drive, Baltimore, MD, 21224 NIH, USA
| | - Yuko Yasui
- Cellular Pathobiology Section, Integrative Neuroscience Branch, Intramural Research Program, National Institute on Drug Abuse, DHHS, IRP, NIH, Triad Technology Center 333 Cassell Drive, Baltimore, MD, 21224 NIH, USA
| | - Yuriko Kimura
- Cellular Pathobiology Section, Integrative Neuroscience Branch, Intramural Research Program, National Institute on Drug Abuse, DHHS, IRP, NIH, Triad Technology Center 333 Cassell Drive, Baltimore, MD, 21224 NIH, USA
| | - Shao-Ming Wang
- Cellular Pathobiology Section, Integrative Neuroscience Branch, Intramural Research Program, National Institute on Drug Abuse, DHHS, IRP, NIH, Triad Technology Center 333 Cassell Drive, Baltimore, MD, 21224 NIH, USA
| | - Nino Sharikadze
- Cellular Pathobiology Section, Integrative Neuroscience Branch, Intramural Research Program, National Institute on Drug Abuse, DHHS, IRP, NIH, Triad Technology Center 333 Cassell Drive, Baltimore, MD, 21224 NIH, USA
| | - Hsiang-En Wu
- Cellular Pathobiology Section, Integrative Neuroscience Branch, Intramural Research Program, National Institute on Drug Abuse, DHHS, IRP, NIH, Triad Technology Center 333 Cassell Drive, Baltimore, MD, 21224 NIH, USA
| | - Tsung-Ping Su
- Cellular Pathobiology Section, Integrative Neuroscience Branch, Intramural Research Program, National Institute on Drug Abuse, DHHS, IRP, NIH, Triad Technology Center 333 Cassell Drive, Baltimore, MD, 21224 NIH, USA
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9
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Abdullah CS, Aishwarya R, Alam S, Remex NS, Morshed M, Nitu S, Miriyala S, Panchatcharam M, Hartman B, King J, Alfrad Nobel Bhuiyan M, Traylor J, Kevil CG, Orr AW, Bhuiyan MS. The molecular role of Sigmar1 in regulating mitochondrial function through mitochondrial localization in cardiomyocytes. Mitochondrion 2022; 62:159-175. [PMID: 34902622 PMCID: PMC8790786 DOI: 10.1016/j.mito.2021.12.002] [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] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Revised: 12/02/2021] [Accepted: 12/06/2021] [Indexed: 01/03/2023]
Abstract
Sigmar1 is a widely expressed molecular chaperone protein in mammalian cell systems. Accumulating research demonstrated the cardioprotective roles of pharmacologic Sigmar1 activation by ligands in preclinical rodent models of cardiac injury. Extensive biochemical and immuno-electron microscopic research demonstrated Sigmar1's sub-cellular localization largely depends on cell and organ types. Despite comprehensive studies, Sigmar1's direct molecular role in cardiomyocytes remains elusive. In the present study, we determined Sigmar1's subcellular localization, transmembrane topology, and function using complementary microscopy, biochemical, and functional assays in cardiomyocytes. Quantum dots in transmission electron microscopy showed Sigmar1 labeled quantum dots on the mitochondrial membranes, lysosomes, and sarcoplasmic reticulum-mitochondrial interface. Subcellular fractionation of heart cell lysates confirmed Sigmar1's localization in purified mitochondria fraction and lysosome fraction. Immunocytochemistry confirmed Sigmar1 colocalization with mitochondrial proteins in isolated adult mouse cardiomyocytes. Sigmar1's mitochondrial localization was further confirmed by Sigmar1 colocalization with Mito-Tracker in isolated mouse heart mitochondria. A series of biochemical experiments, including alkaline extraction and proteinase K treatment of purified heart mitochondria, demonstrated Sigmar1 as an integral mitochondrial membrane protein. Sigmar1's structural requirement for mitochondrial localization was determined by expressing FLAG-tagged Sigmar1 fragments in cells. Full-length Sigmar1 and Sigmar1's C terminal-deletion fragments were able to localize to the mitochondrial membrane, whereas N-terminal deletion fragment was unable to incorporate into the mitochondria. Finally, functional assays using extracellular flux analyzer and high-resolution respirometry showed Sigmar1 siRNA knockdown significantly altered mitochondrial respiration in cardiomyocytes. Overall, we found that Sigmar1 localizes to mitochondrial membranes and is indispensable for maintaining mitochondrial respiratory homeostasis in cardiomyocytes.
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Affiliation(s)
- Chowdhury S Abdullah
- Department of Pathology and Translational Pathobiology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA 71103, USA
| | - Richa Aishwarya
- Department of Pathology and Translational Pathobiology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA 71103, USA
| | - Shafiul Alam
- Department of Pathology and Translational Pathobiology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA 71103, USA
| | - Naznin Sultana Remex
- Department of Molecular and Cellular Physiology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA 71103, USA
| | - Mahboob Morshed
- Department of Pathology and Translational Pathobiology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA 71103, USA
| | - Sadia Nitu
- Department of Pathology and Translational Pathobiology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA 71103, USA
| | - Sumitra Miriyala
- Department of Cellular Biology and Anatomy, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA 71103, USA
| | - Manikandan Panchatcharam
- Department of Cellular Biology and Anatomy, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA 71103, USA
| | - Brandon Hartman
- Department of Pathology and Translational Pathobiology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA 71103, USA
| | - Judy King
- Department of Pathology and Translational Pathobiology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA 71103, USA
| | | | - James Traylor
- Department of Pathology and Translational Pathobiology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA 71103, USA
| | - Christopher G Kevil
- Department of Pathology and Translational Pathobiology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA 71103, USA; Department of Molecular and Cellular Physiology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA 71103, USA; Department of Cellular Biology and Anatomy, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA 71103, USA
| | - A Wayne Orr
- Department of Pathology and Translational Pathobiology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA 71103, USA; Department of Molecular and Cellular Physiology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA 71103, USA; Department of Cellular Biology and Anatomy, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA 71103, USA
| | - Md Shenuarin Bhuiyan
- Department of Pathology and Translational Pathobiology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA 71103, USA; Department of Molecular and Cellular Physiology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA 71103, USA.
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10
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Current development of sigma-2 receptor radioligands as potential tumor imaging agents. Bioorg Chem 2021; 115:105163. [PMID: 34289426 DOI: 10.1016/j.bioorg.2021.105163] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2021] [Revised: 07/05/2021] [Accepted: 07/08/2021] [Indexed: 12/24/2022]
Abstract
Sigma receptors are transmembrane proteins with two different subtypes: σ1 and σ2. Because of its overexpression in tumors, the σ2 receptor (σ2R) is a well-known biomarker for cancer cells. A large number of small-molecule ligands for the σ2Rs have been identified and tested for imaging the proliferative status of tumors using single photon emission computed tomography (SPECT) and positron emission tomography (PET). These small molecules include derivatives of bicyclic amines, indoles, cyclohexylpiperazines and tetrahydroisoquinolines. This review discusses various aspects of small molecule ligands, such as chemical composition, labeling strategy, affinity for σ2Rs, and in vitro/in vivo investigations. The recent studies described here could be useful for the development of σ2R radioligands as potential tumor imaging agents.
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11
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Aishwarya R, Abdullah CS, Morshed M, Remex NS, Bhuiyan MS. Sigmar1's Molecular, Cellular, and Biological Functions in Regulating Cellular Pathophysiology. Front Physiol 2021; 12:705575. [PMID: 34305655 PMCID: PMC8293995 DOI: 10.3389/fphys.2021.705575] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Accepted: 06/07/2021] [Indexed: 12/11/2022] Open
Abstract
The Sigma 1 receptor (Sigmar1) is a ubiquitously expressed multifunctional inter-organelle signaling chaperone protein playing a diverse role in cellular survival. Recessive mutation in Sigmar1 have been identified as a causative gene for neuronal and neuromuscular disorder. Since the discovery over 40 years ago, Sigmar1 has been shown to contribute to numerous cellular functions, including ion channel regulation, protein quality control, endoplasmic reticulum-mitochondrial communication, lipid metabolism, mitochondrial function, autophagy activation, and involved in cellular survival. Alterations in Sigmar1’s subcellular localization, expression, and signaling has been implicated in the progression of a wide range of diseases, such as neurodegenerative diseases, ischemic brain injury, cardiovascular diseases, diabetic retinopathy, cancer, and drug addiction. The goal of this review is to summarize the current knowledge of Sigmar1 biology focusing the recent discoveries on Sigmar1’s molecular, cellular, pathophysiological, and biological functions.
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Affiliation(s)
- Richa Aishwarya
- Department of Molecular and Cellular Physiology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA, United States
| | - Chowdhury S Abdullah
- Department of Pathology and Translational Pathobiology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA, United States
| | - Mahboob Morshed
- Department of Pathology and Translational Pathobiology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA, United States
| | - Naznin Sultana Remex
- Department of Molecular and Cellular Physiology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA, United States
| | - Md Shenuarin Bhuiyan
- Department of Molecular and Cellular Physiology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA, United States.,Department of Pathology and Translational Pathobiology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA, United States
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12
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Kopp N, Civenni G, Marson D, Laurini E, Pricl S, Catapano CV, Humpf HU, Almansa C, Nieto FR, Schepmann D, Wünsch B. Chemoenzymatic synthesis of 2,6-disubstituted tetrahydropyrans with high σ 1 receptor affinity, antitumor and analgesic activity. Eur J Med Chem 2021; 219:113443. [PMID: 33901806 DOI: 10.1016/j.ejmech.2021.113443] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 03/22/2021] [Accepted: 03/29/2021] [Indexed: 02/06/2023]
Abstract
1,3-Dioxanes 1 and cyclohexanes 2 bearing a phenyl ring and an aminoethyl moiety in 1,3-relationship to each other represent highly potent σ1 receptor antagonists. In order to increase the chemical stability of the acetalic 1,3-dioxanes 1 and the polarity of the cyclohexanes 2, tetrahydropyran derivatives 3 equipped with the same substituents were designed, synthesized and pharmacologically evaluated. The key step of the synthesis was a lipase-catalyzed enantioselective acetylation of the alcohol (R)-5 leading finally to enantiomerically pure test compounds 3a-g. With respect to σ1 receptor affinity and selectivity over a broad range of related (σ2, PCP binding site) and further targets, the enantiomeric benzylamines 3a and cyclohexylmethylamines 3b represent the most promising drug candidates of this series. However, the eudismic ratio for σ1 binding is only in the range of 2.5-3.3. Classical molecular dynamics (MD) simulations confirmed the same binding pose for both the tetrahydropyran 3 and cyclohexane derivatives 2 at the σ1 receptor, according to which: i) the protonated amino moiety of (2S,6R)-3a engages the same key polar interactions with Glu172 (ionic) and Phe107 (π-cation), ii) the lipophilic parts of (2S,6R)-3a are hosted in three hydrophobic regions of the σ1 receptor, and iii) the O-atom of the tetrahydropyran derivatives 3 does not show a relevant interaction with the σ1 receptor. Further in silico evidences obtained by the application of free energy perturbation and steered MD techniques fully supported the experimentally observed difference in receptor/ligand affinities. Tetrahydropyrans 3 require a lower dissociative force peak than cyclohexane analogs 2. Enantiomeric benzylamines 3a and cyclohexylmethylamines 3b were able to inhibit the growth of the androgen negative human prostate cancer cell line DU145. The cyclohexylmethylamine (2S,6R)-3b showed the highest σ1 affinity (Ki(σ1) = 0.95 nM) and the highest analgesic activity in vivo (67%).
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Affiliation(s)
- Nicole Kopp
- Institut für Pharmazeutische und Medizinische Chemie, Westfälische Wilhelms-Universität Münster, Corrensstraße 48, D-48149, Münster, Germany
| | - Gianluca Civenni
- Institute of Oncology Research, Università della Svizzera Italiana (USI), Via Vincenzo Vela 6, CH-6500, Bellinzona, Switzerland
| | - Domenico Marson
- Molecular Biology and Nanotechnology Laboratory (MolBNL@UniTS), DEA, University of Trieste, 34127, Trieste, Italy
| | - Erik Laurini
- Molecular Biology and Nanotechnology Laboratory (MolBNL@UniTS), DEA, University of Trieste, 34127, Trieste, Italy
| | - Sabrina Pricl
- Molecular Biology and Nanotechnology Laboratory (MolBNL@UniTS), DEA, University of Trieste, 34127, Trieste, Italy; Department of General Biophysics, Faculty of Biology and Environmental Protection, University of Lodz, Lodz, Poland
| | - Carlo V Catapano
- Institute of Oncology Research, Università della Svizzera Italiana (USI), Via Vincenzo Vela 6, CH-6500, Bellinzona, Switzerland
| | - Hans-Ulrich Humpf
- Institut für Lebensmittelchemie, Westfälische Wilhelms-Universität Münster, Corrensstraße 45, D-48149, Münster, Germany
| | - Carmen Almansa
- Esteve Pharmaceuticals S.A., Baldiri Reixach 4-8, 08028, Barcelona, Spain
| | - Francisco Rafael Nieto
- Department of Pharmacology and Neurosciences Institute (Biomedical Research Center), University of Granada and Biosanitary Research Institute, 18010, Granada, Spain
| | - Dirk Schepmann
- Institut für Pharmazeutische und Medizinische Chemie, Westfälische Wilhelms-Universität Münster, Corrensstraße 48, D-48149, Münster, Germany
| | - Bernhard Wünsch
- Institut für Pharmazeutische und Medizinische Chemie, Westfälische Wilhelms-Universität Münster, Corrensstraße 48, D-48149, Münster, Germany; GRK 2515, Chemical Biology of Ion Channels (Chembion), Westfälische Wilhelms-Universität Münster, Germany.
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13
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Torres-Gómez H, Daniliuc C, Schepmann D, Laurini E, Pricl S, Wünsch B. Propellanes as Rigid Scaffolds for the Stereodefined Attachment of σ-Pharmacophoric Structural Elements to Achieve σ Affinity. Int J Mol Sci 2021; 22:ijms22115685. [PMID: 34073622 PMCID: PMC8199339 DOI: 10.3390/ijms22115685] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 05/20/2021] [Accepted: 05/22/2021] [Indexed: 01/07/2023] Open
Abstract
Following the concept of conformationally restriction of ligands to achieve high receptor affinity, we exploited the propellane system as rigid scaffold allowing the stereodefined attachment of various substituents. Three types of ligands were designed, synthesized and pharmacologically evaluated as σ1 receptor ligands. Propellanes with (1) a 2-methoxy-5-methylphenylcarbamate group at the "left" five-membered ring and various amino groups on the "right" side; (2) benzylamino or analogous amino moieties on the "right" side and various substituents at the left five-membered ring and (3) various urea derivatives at one five-membered ring were investigated. The benzylamino substituted carbamate syn,syn-4a showed the highest σ1 affinity within the group of four stereoisomers emphasizing the importance of the stereochemistry. The cyclohexylmethylamine 18 without further substituents at the propellane scaffold revealed unexpectedly high σ1 affinity (Ki = 34 nM) confirming the relevance of the bioisosteric replacement of the benzylamino moiety by the cyclohexylmethylamino moiety. Reduction of the distance between the basic amino moiety and the "left" hydrophobic region by incorporation of the amino moiety into the propellane scaffold resulted in azapropellanes with particular high σ1 affinity. As shown for the propellanamine 18, removal of the carbamate moiety increased the σ1 affinity of 9a (Ki = 17 nM) considerably. Replacement of the basic amino moiety by H-bond forming urea did not lead to potent σ ligands. According to molecular dynamics simulations, both azapropellanes anti-5 and 9a as well as propellane 18 adopt binding poses at the σ1 receptor, which result in energetic values correlating well with their different σ1 affinities. The affinity of the ligands is enthalpy driven. The additional interactions of the carbamate moiety of anti-5 with the σ1 receptor protein cannot compensate the suboptimal orientations of the rigid propellane and its N-benzyl moiety within the σ1 receptor-binding pocket, which explains the higher σ1 affinity of the unsubstituted azapropellane 9a.
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Affiliation(s)
- Héctor Torres-Gómez
- Department of Chemistry and Pharamcy, Institut für Pharmazeutische und Medizinische Chemie, Westfälische Wilhelms-Universität Münster, Corrensstraße 48, D-48149 Münster, Germany; (H.T.-G.); (D.S.)
| | - Constantin Daniliuc
- Department of Chemistry and Pharamcy, Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 40, D-48149 Münster, Germany;
| | - Dirk Schepmann
- Department of Chemistry and Pharamcy, Institut für Pharmazeutische und Medizinische Chemie, Westfälische Wilhelms-Universität Münster, Corrensstraße 48, D-48149 Münster, Germany; (H.T.-G.); (D.S.)
| | - Erik Laurini
- Molecular Biology and Nanotechnology Laboratory (MolBNL@UniTS), Department of Engineering and Architecture, University of Trieste, 34127 Trieste, Italy; (S.P.); (E.L.)
| | - Sabrina Pricl
- Molecular Biology and Nanotechnology Laboratory (MolBNL@UniTS), Department of Engineering and Architecture, University of Trieste, 34127 Trieste, Italy; (S.P.); (E.L.)
- Department of General Biophysics, Faculty of Biology and Environmental Protection, University of Lodz, 90-236 Lodz, Poland
| | - Bernhard Wünsch
- Department of Chemistry and Pharamcy, Institut für Pharmazeutische und Medizinische Chemie, Westfälische Wilhelms-Universität Münster, Corrensstraße 48, D-48149 Münster, Germany; (H.T.-G.); (D.S.)
- GRK 2515, Chemical Biology of Ion Channels (Chembion), Westfälische Wilhelms-Universität Münster, D-48149 Münster, Germany
- Correspondence: ; Tel.: +49-251-833-3311; Fax: +49-251-833-2144
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14
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Prasanth MI, Malar DS, Tencomnao T, Brimson JM. The emerging role of the sigma-1 receptor in autophagy: hand-in-hand targets for the treatment of Alzheimer's. Expert Opin Ther Targets 2021; 25:401-414. [PMID: 34110944 DOI: 10.1080/14728222.2021.1939681] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Accepted: 06/03/2021] [Indexed: 01/18/2023]
Abstract
INTRODUCTION Autophagy is a cellular catabolic mechanism that helps clear damaged cellular components and is essential for normal cellular and tissue function. The sigma-1 receptor (σ-1R) is a chaperone protein involved in signal transduction, neurite outgrowth, and plasticity, improving memory, and neuroprotection. Recent evidence shows that σ-1R can promote autophagy. Autophagy activation by the σ-1Rs along with other neuroprotective effects makes it an interesting target for the treatment of Alzheimer's disease. AF710B, T-817 MA, and ANAVEX2-73 are some of the σ-1R agonists which have shown promising results and have entered clinical trials. These molecules have also been found to induce autophagy and show cytoprotective effects in cellular models. AREAS COVERED This review provides insight into the current understanding of σ-1R functions related to autophagy and their role in alleviating AD. EXPERT OPINION We propose a mechanism through which the activation of σ-1R and autophagy could alter amyloid precursor protein processing to inhibit amyloid-β production by reconstituting cholesterol and gangliosides in the lipid raft to offer neuroprotection against AD. Future AD treatment could involve the combined targeting of the σ-1R and autophagy activation. We suggest that future studies investigate the link between autophagy the σ-1R and AD.
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Affiliation(s)
- Mani Iyer Prasanth
- Natural Products for Neuroprotection and Anti-ageing Research Unit, Faculty of Allied Health Sciences, Chulalongkorn University, Bangkok, Thailand
- Department of Clinical Chemistry, Faculty of Allied Health Sciences, Chulalongkorn University, Bangkok, Thailand
| | - Dicson Sheeja Malar
- Natural Products for Neuroprotection and Anti-ageing Research Unit, Faculty of Allied Health Sciences, Chulalongkorn University, Bangkok, Thailand
- Department of Clinical Chemistry, Faculty of Allied Health Sciences, Chulalongkorn University, Bangkok, Thailand
| | - Tewin Tencomnao
- Natural Products for Neuroprotection and Anti-ageing Research Unit, Faculty of Allied Health Sciences, Chulalongkorn University, Bangkok, Thailand
- Department of Clinical Chemistry, Faculty of Allied Health Sciences, Chulalongkorn University, Bangkok, Thailand
| | - James Michael Brimson
- Natural Products for Neuroprotection and Anti-ageing Research Unit, Faculty of Allied Health Sciences, Chulalongkorn University, Bangkok, Thailand
- Department of Clinical Chemistry, Faculty of Allied Health Sciences, Chulalongkorn University, Bangkok, Thailand
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15
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Agha H, McCurdy CR. In vitro and in vivo sigma 1 receptor imaging studies in different disease states. RSC Med Chem 2021; 12:154-177. [PMID: 34046607 PMCID: PMC8127618 DOI: 10.1039/d0md00186d] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Accepted: 09/02/2020] [Indexed: 12/11/2022] Open
Abstract
The sigma receptor system has been classified into two distinct subtypes, sigma 1 (σ1R) and sigma 2 (σ2R). Sigma 1 receptors (σ1Rs) are involved in many neurodegenerative diseases and different central nervous system disorders such as Alzheimer's disease, Parkinson's disease, schizophrenia, and drug addiction, and pain. This makes them attractive targets for developing radioligands as tools to gain a better understanding of disease pathophysiology and clinical diagnosis. Over the years, several σ1R radioligands have been developed to image the changes in σ1R distribution and density providing insights into their role in disease development. Moreover, the involvement of both σ1Rs and σ2Rs with cancer make these ligands, especially those that are σ2R selective, great tools for imaging different types of tumors. This review will discuss the principles of molecular imaging using PET and SPECT, known σ1R radioligands and their applications for labelling σ1Rs under different disease conditions. Furthermore, this review will highlight σ1R radioligands that have demonstrated considerable potential as biomarkers, and an opportunity to fulfill the ultimate goal of better healthcare outcomes and improving human health.
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Affiliation(s)
- Hebaalla Agha
- Department of Medicinal Chemistry, College of Pharmacy, University of Florida Gainesville FL 32610 USA +(352) 273 7705 +1 (352) 294 8691
| | - Christopher R McCurdy
- Department of Medicinal Chemistry, College of Pharmacy, University of Florida Gainesville FL 32610 USA +(352) 273 7705 +1 (352) 294 8691
- UF Translational Drug Development Core, University of Florida Gainesville FL 32610 USA
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16
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Kopp N, Holtschulte C, Börgel F, Lehmkuhl K, Friedland K, Civenni G, Laurini E, Catapano CV, Pricl S, Humpf HU, Schepmann D, Wünsch B. Novel σ 1 antagonists designed for tumor therapy: Structure - activity relationships of aminoethyl substituted cyclohexanes. Eur J Med Chem 2021; 210:112950. [PMID: 33148494 DOI: 10.1016/j.ejmech.2020.112950] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Revised: 09/19/2020] [Accepted: 10/14/2020] [Indexed: 12/15/2022]
Abstract
Depending on the substitution pattern and stereochemistry, 1,3-dioxanes 1 with an aminoethyl moiety in 4-position represent potent σ1 receptor antagonists. In order to increase the stability, a cyclohexane ring first replaced the acetalic 1, 3-dioxane ring of 1. A large set of aminoethyl substituted cyclohexane derivatives was prepared in a six-step synthesis. All enantiomers and diastereomers were separated by chiral HPLC at the stage of the primary alcohol 7, and their absolute configuration was determined by CD spectroscopy. Neither the relative nor the absolute configuration had a large impact on the σ1 affinity. The highest σ1 affinity was found for cis-configured benzylamines (1R,3S)-11 (Ki = 0.61 nM) and (1S,3R)-11 (Ki = 1.3 nM). Molecular dynamics simulations showed that binding of (1R,3S)-11 at the σ1 receptor is stabilized by the typical polar interaction of the protonated amino moiety with the carboxy group of E172 which is optimally oriented by an H-bond interaction with Y103. The lipophilic interaction of I124 with the N-substituent also contributes to the high σ1 affinity of the benzylamines. The antagonistic activity was determined in a Ca2+ influx assay in retinal ganglion cells. The enantiomeric cis-configured benzylamines (1R,3S)-11 and (1S,3R)-11 were able to inhibit the growth of DU145 cells, a highly aggressive human prostate tumor cell line. Moreover, cis-11 could also inhibit the growth of further human tumor cells expressing σ1 receptors. The experimentally determined logD7.4 value of 3.13 for (1R,3S)-11 is in a promising range regarding membrane penetration. After incubation with mouse liver microsomes and NADPH for 90 min, 43% of the parent (1R,3S)-11 remained unchanged, indicating intermediate metabolic stability. Altogether, nine metabolites including one glutathione adduct were detected by means of LC-MS analysis.
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Affiliation(s)
- Nicole Kopp
- Institut für Pharmazeutische und Medizinische Chemie, Westfälische Wilhelms-Universität Münster, Corrensstraße 48, D-48149 Münster, Germany
| | - Catharina Holtschulte
- Institut für Pharmazeutische und Medizinische Chemie, Westfälische Wilhelms-Universität Münster, Corrensstraße 48, D-48149 Münster, Germany
| | - Frederik Börgel
- Institut für Pharmazeutische und Medizinische Chemie, Westfälische Wilhelms-Universität Münster, Corrensstraße 48, D-48149 Münster, Germany
| | - Kirstin Lehmkuhl
- Institut für Pharmazeutische und Medizinische Chemie, Westfälische Wilhelms-Universität Münster, Corrensstraße 48, D-48149 Münster, Germany
| | - Kristina Friedland
- Pharmacology and Toxicology, Pharmacy and Biochemistry, Johannes Gutenberg University, Staudingerweg 5, 55128 Mainz, Germany
| | - Gianluca Civenni
- Institute of Oncology Research, Universita Della Svizzera Italiana (USI), Via Vincenzo Vela 6, CH-6500 Bellinzona, Switzerland
| | - Erik Laurini
- Molecular Biology and Nanotechnology Laboratory (MolBNL@UniTS), DEA, University of Trieste, 34127, Trieste, Italy
| | - Carlo V Catapano
- Institute of Oncology Research, Universita Della Svizzera Italiana (USI), Via Vincenzo Vela 6, CH-6500 Bellinzona, Switzerland
| | - Sabrina Pricl
- Molecular Biology and Nanotechnology Laboratory (MolBNL@UniTS), DEA, University of Trieste, 34127, Trieste, Italy; Department of General Biophysics, Faculty of Biology and Environmental Protection, University of Lodz, Lodz, Poland
| | - Hans-Ulrich Humpf
- Institut für Lebensmittelchemie, Westfälische Wilhelms-Universität Münster, Corrensstraße 45, D-48149 Münster, Germany
| | - Dirk Schepmann
- Institut für Pharmazeutische und Medizinische Chemie, Westfälische Wilhelms-Universität Münster, Corrensstraße 48, D-48149 Münster, Germany
| | - Bernhard Wünsch
- Institut für Pharmazeutische und Medizinische Chemie, Westfälische Wilhelms-Universität Münster, Corrensstraße 48, D-48149 Münster, Germany; Cells-in-Motion Cluster of Excellence (EXC 1003 - CiM), Westfälische Wilhelms-Universität Münster, Germany.
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17
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Brimson JM, Brimson S, Chomchoei C, Tencomnao T. Using sigma-ligands as part of a multi-receptor approach to target diseases of the brain. Expert Opin Ther Targets 2020; 24:1009-1028. [PMID: 32746649 DOI: 10.1080/14728222.2020.1805435] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
INTRODUCTION The sigma receptors are found abundantly in the central nervous system and are targets for the treatment of various diseases, including Alzheimer's (AD), Parkinson's (PD), Huntington's disease (HD), depression, amyotrophic lateral sclerosis (ALS), and multiple sclerosis (MS). However, for many of these diseases, other receptors and targets have been the focus of the most, such as acetylcholine esterase inhibitors in Alzheimer's and dopamine replacement in Parkinson's. The currently available drugs for these diseases have limited success resulting in the requirement of an alternative approach to their treatment. AREAS COVERED In this review, we discuss the potential role of the sigma receptors and their ligands as part of a multi receptor approach in the treatment of the diseases mentioned above. The literature reviewed was obtained through searches in databases, including PubMed, Web of Science, Google Scholar, and Scopus. EXPERT OPINION Given sigma receptor agonists provide neuroprotection along with other benefits such as potentiating the effects of other receptors, further development of multi-receptor targeting ligands, and or the development of multi-drug combinations to target multiple receptors may prove beneficial in the future treatment of degenerative diseases of the CNS, especially when coupled with better diagnostic techniques.
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Affiliation(s)
- James Michael Brimson
- Age-related Inflammation and Degeneration Research Unit, Department of Clinical Chemistry, Faculty of Allied Health Sciences, Chulalongkorn University , Bangkok, Thailand
| | - Sirikalaya Brimson
- Department of Clinical Microscopy, Faculty of Allied Health Sciences, Chulalongkorn University , Bangkok, Thailand
| | - Chanichon Chomchoei
- Department of Clinical Microscopy, Faculty of Allied Health Sciences, Chulalongkorn University , Bangkok, Thailand
| | - Tewin Tencomnao
- Age-related Inflammation and Degeneration Research Unit, Department of Clinical Chemistry, Faculty of Allied Health Sciences, Chulalongkorn University , Bangkok, Thailand
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18
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Rossino G, Orellana I, Caballero J, Schepmann D, Wünsch B, Rui M, Rossi D, González-Avendaño M, Collina S, Vergara-Jaque A. New Insights into the Opening of the Occluded Ligand-Binding Pocket of Sigma1 Receptor: Binding of a Novel Bivalent RC-33 Derivative. J Chem Inf Model 2019; 60:756-765. [DOI: 10.1021/acs.jcim.9b00649] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Giacomo Rossino
- Department of Drug Sciences, University of Pavia, Viale Taramelli 12, 27100 Pavia, Italy
| | - Ivana Orellana
- Center for Bioinformatics and Molecular Simulation, Universidad de Talca, 1 Poniente, 1141 Talca, Chile
| | - Julio Caballero
- Center for Bioinformatics and Molecular Simulation, Universidad de Talca, 1 Poniente, 1141 Talca, Chile
| | - Dirk Schepmann
- Institute of Pharmaceutical and Medicinal Chemistry, University of Muenster, Correnstrasse 48, 48149 Münster, Germany
| | - Bernhard Wünsch
- Institute of Pharmaceutical and Medicinal Chemistry, University of Muenster, Correnstrasse 48, 48149 Münster, Germany
| | - Marta Rui
- Department of Drug Sciences, University of Pavia, Viale Taramelli 12, 27100 Pavia, Italy
| | - Daniela Rossi
- Department of Drug Sciences, University of Pavia, Viale Taramelli 12, 27100 Pavia, Italy
| | - Mariela González-Avendaño
- Center for Bioinformatics and Molecular Simulation, Universidad de Talca, 1 Poniente, 1141 Talca, Chile
| | - Simona Collina
- Department of Drug Sciences, University of Pavia, Viale Taramelli 12, 27100 Pavia, Italy
| | - Ariela Vergara-Jaque
- Center for Bioinformatics and Molecular Simulation, Universidad de Talca, 1 Poniente, 1141 Talca, Chile
- Multidisciplinary Scientific Nucleus, Universidad de Talca, 1 Poniente, 1141 Talca, Chile
- Millennium Nucleus of Ion Channels-associated Diseases (MiNICAD), Santiago, Chile
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19
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Asong G, Zhu XY, Bricker B, Andey T, Amissah F, Lamango N, Ablordeppey SY. New analogs of SYA013 as sigma-2 ligands with anticancer activity. Bioorg Med Chem 2019; 27:2629-2636. [PMID: 30987780 PMCID: PMC6536312 DOI: 10.1016/j.bmc.2019.04.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2019] [Revised: 04/04/2019] [Accepted: 04/06/2019] [Indexed: 12/20/2022]
Abstract
Our previous study has revealed 4-(4-(4-chlorophenyl)-1,4-diazepan-1-yl)-1-(4-fluorophenyl)butan-1-one·2HCl (SYA013) 1 as a sigma ligand with moderate selectivity for the sigma-2 receptor. Given the overexpression of sigma receptors in solid tumors and reports of sigma ligands with anticancer activities, we selected 1 for evaluation in several solid tumor cell lines. In addition, we have synthesized new analogs of 1 and now report that several of them bind preferentially at the sigma-2 receptor and have shown inhibition of several cancer cell lines including MDA-MB-231, MDA-MB-486, A549, PC-3, MIA PaCa-2 and Panc-1 cells. In particular, compounds 1 and 12 have demonstrated sub-micromolar activity against the Panc-1 cell line. It has also been observed that several of these compounds demonstrate selective toxicity toward cancer cells, when compared to normal cells.
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Affiliation(s)
- Gladys Asong
- Division of Basic Pharmaceutical Sciences, College of Pharmacy and Pharmaceutical Sciences, Florida A&M University, Tallahassee, FL 32307, USA
| | - Xue Y Zhu
- Division of Basic Pharmaceutical Sciences, College of Pharmacy and Pharmaceutical Sciences, Florida A&M University, Tallahassee, FL 32307, USA
| | - Barbara Bricker
- Division of Basic Pharmaceutical Sciences, College of Pharmacy and Pharmaceutical Sciences, Florida A&M University, Tallahassee, FL 32307, USA
| | - Terrick Andey
- Division of Basic Pharmaceutical Sciences, College of Pharmacy and Pharmaceutical Sciences, Florida A&M University, Tallahassee, FL 32307, USA
| | - Felix Amissah
- Division of Basic Pharmaceutical Sciences, College of Pharmacy and Pharmaceutical Sciences, Florida A&M University, Tallahassee, FL 32307, USA
| | - Nazarius Lamango
- Division of Basic Pharmaceutical Sciences, College of Pharmacy and Pharmaceutical Sciences, Florida A&M University, Tallahassee, FL 32307, USA
| | - Seth Y Ablordeppey
- Division of Basic Pharmaceutical Sciences, College of Pharmacy and Pharmaceutical Sciences, Florida A&M University, Tallahassee, FL 32307, USA
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Pascual R, Almansa C, Plata-Salamán C, Vela JM. A New Pharmacophore Model for the Design of Sigma-1 Ligands Validated on a Large Experimental Dataset. Front Pharmacol 2019; 10:519. [PMID: 31214020 PMCID: PMC6555132 DOI: 10.3389/fphar.2019.00519] [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: 02/04/2019] [Accepted: 04/24/2019] [Indexed: 11/13/2022] Open
Abstract
The recent publication of the σ1R crystal structure is an important cornerstone for the derivation of more accurate activity prediction models. We report here a comparative study involving a set of more than 25,000 structures from our internal database that had been screened for σ1R affinity. Using the recently published crystal structure, 5HK1, two new pharmacophore models were generated. The first one, 5HK1-Ph.A, was obtained by an algorithm that identifies the most important receptor-ligand interactions including volume restrictions enforced by the atomic structure of the recognition site. The second, 5HK1-Ph.B, resulted from a manual edition of the first one by the fusion of two hydrophobic (HYD) features. Finally, we also docked the database using a high throughput docking technique and scored the resulting poses with seven different scoring functions. Statistical performance measures were obtained for the two models, comparing them with previously published σ1R pharmacophores (Hit Rate, sensitivity, specificity, and Receiver Operator Characteristic) and 5HK1-Ph.B emerged as the best one in discriminating between active and inactive compounds, with a ROC-AUC value above 0.8 and enrichment values above 3 at different fractions of screened samples. 5HK1-Ph.B also showed better results than the direct docking, which may be due to the rigidity of the crystal structure in the docking process (i.e., feature tolerances in the pharmacophore model). Additionally, the impact of the HYD interactions and the penalty for desolvating ligands with polar atoms may be not adequately captured by scoring functions, whereas HYD groups filling up such regions of the binding site are entailed in the pharmacophore model. Altogether, using annotated data from a large and diverse compound collection together with crystal structure information provides a sound basis for the generation and validation of predictive models to design new molecules.
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Affiliation(s)
- Rosalia Pascual
- ESTEVE Pharmaceuticals S.A., Drug Discovery and Preclinical Development, Barcelona, Spain
| | - Carmen Almansa
- ESTEVE Pharmaceuticals S.A., Drug Discovery and Preclinical Development, Barcelona, Spain
| | - Carlos Plata-Salamán
- ESTEVE Pharmaceuticals S.A., Drug Discovery and Preclinical Development, Barcelona, Spain
| | - José Miguel Vela
- ESTEVE Pharmaceuticals S.A., Drug Discovery and Preclinical Development, Barcelona, Spain
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21
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Romero L, Portillo-Salido E. Trends in Sigma-1 Receptor Research: A 25-Year Bibliometric Analysis. Front Pharmacol 2019; 10:564. [PMID: 31178733 PMCID: PMC6543269 DOI: 10.3389/fphar.2019.00564] [Citation(s) in RCA: 62] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Accepted: 05/06/2019] [Indexed: 12/14/2022] Open
Abstract
Purpose: There are previous reviews focused on Sigma-1 receptor but no bibliometric studies examining this field as a whole. This article aims to present a global view of Sigma-1 receptor research and its intellectual structure. Methods: We used bibliometric indicators of a basic nature as well as techniques for the visualization and analysis of networks of scientific information extracted from Scopus database. Results: In total, 1,102 articles from 1992 to 2017 were identified. The growth in the production of articles is not constant over time, with periods of stagnation of approximately 5 years. Only 247 authors have five or more publications. The authors appear grouped in relatively independent clusters, thus suggesting a low level of collaborations between those dedicated to the Sigma-1 receptor. The United States was the country with the highest production followed by Japan and Germany. Spain, Japan, and Italy showed the highest per million inhabitants ratio. The highest citation/article ratio was reached in France, United States, and Canada. The leading institutions were the University of Münster, the National Institutes of Health, ESTEVE, and INSERM. The top authors in number of publications were Wünsch-B, Schepmann-D, and Maurice-T. Hayashi-T, Su-TP and Bowen-WD showed the highest citations per article. The article by Hayashi-T and Su-TP in Cell (2007) describing the Sigma-1 receptor as a chaperone protein is the top cited reference. Cluster labeling from author co-citation analysis shows that research has been focused on specific diseases such as addiction, neuroprotection and neurodegenerative diseases, psychiatric disorders, and pain. High-frequency terms in author keywords suggest that the research efforts in some areas such as neuroimaging, cocaine addiction or psychiatric disorders have declined over time, while others such as neurodegenerative diseases or pain are currently most popular. Perspective: A greater involvement of the scientific community, with an increase in the scientific production related to Sigma-1, is desirable. Additional boost needed to improve research performance is likely to come from combining data from different laboratories to overcome the limitations of individual approaches. The resulting maps are a useful and attractive tool for the Sigma-1 receptor research community, as they reveal the main lines of exploration at a glance.
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Affiliation(s)
- Luz Romero
- Drug Discovery and Preclinical Development, Esteve Pharmaceuticals, Parc Científic de Barcelona, Barcelona, Spain
| | - Enrique Portillo-Salido
- Drug Discovery and Preclinical Development, Esteve Pharmaceuticals, Parc Científic de Barcelona, Barcelona, Spain
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22
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Abstract
More than four decades passed since sigma receptors were first mentioned. Since then, existence of at least two receptor subtypes and their tissue distributions have been proposed. Nowadays, it is clear, that sigma receptors are unique ubiquitous proteins with pluripotent function, which can interact with so many different classes of proteins. As the endoplasmic resident proteins, they work as molecular chaperones - accompany various proteins during their folding, ensure trafficking of the maturated proteins between cellular organelles and regulate their functions. In the heart, sigma receptor type 1 is more dominant. Cardiac sigma 1 receptors regulate response to endoplasmic reticulum stress, modulates calcium signaling in cardiomyocyte and can affect function of voltage-gated ion channels. They contributed in pathophysiology of cardiac hypertrophy, heart failure and many other cardiovascular disorders. Therefore, sigma receptors are potential novel targets for specific treatment of cardiovascular diseases.
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Affiliation(s)
- T Stracina
- Department of Physiology, Faculty of Medicine, Masaryk University, Brno, Czech Republic.
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23
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Affiliation(s)
- Felix J Kim
- Department of Cancer Biology, Thomas Jefferson University, Philadelphia, PA, USA
- Sidney Kimmel Cancer Center at Thomas Jefferson University, Philadelphia, PA, USA
| | - Gavril W Pasternak
- Department of Neurology and Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, NY, USA.
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24
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Smith SB, Wang J, Cui X, Mysona BA, Zhao J, Bollinger KE. Sigma 1 receptor: A novel therapeutic target in retinal disease. Prog Retin Eye Res 2018; 67:130-149. [PMID: 30075336 PMCID: PMC6557374 DOI: 10.1016/j.preteyeres.2018.07.003] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Revised: 07/27/2018] [Accepted: 07/30/2018] [Indexed: 02/08/2023]
Abstract
Retinal degenerative diseases are major causes of untreatable blindness worldwide and efficacious treatments for these diseases are sorely needed. A novel target for treatment of retinal disease is the transmembrane protein Sigma 1 Receptor (Sig1R). This enigmatic protein is an evolutionary isolate with no known homology to any other protein. Sig1R was originally thought to be an opioid receptor. That notion has been dispelled and more recent pharmacological and molecular studies suggest that it is a pluripotent modulator with a number of biological functions, many of which are relevant to retinal disease. This review provides an overview of the discovery of Sig1R and early pharmacologic studies that led to the cloning of the Sig1R gene and eventual elucidation of its crystal structure. Studies of Sig1R in the eye were not reported until the late 1990s, but since that time there has been increasing interest in the potential role of Sig1R as a target for retinal disease. Studies have focused on elucidating the mechanism(s) of Sig1R function in retina including calcium regulation, modulation of oxidative stress, ion channel regulation and molecular chaperone activity. Mechanistic studies have been performed in isolated retinal cells, such as Müller glial cells, microglial cells, optic nerve head astrocytes and retinal ganglion cells as well as in the intact retina. Several compelling studies have provided evidence of powerful in vivo neuroprotective effects against ganglion cell loss as well as photoreceptor cell loss. Also described are studies that have examined retinal structure/function in various models of retinal disease in which Sig1R is absent and reveal that these phenotypes are accelerated compared to retinas of animals that express Sig1R. The collective evidence from analysis of studies over the past 20 years is that Sig1R plays a key role in modulating retinal cellular stress and that it holds great promise as a target in retinal neurodegenerative disease.
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Affiliation(s)
- Sylvia B Smith
- Department of Cellular Biology and Anatomy, Medical College of Georgia at Augusta University, Augusta, GA, USA; The James and Jean Culver Vision Discovery Institute, Augusta University, Augusta, GA, USA; Department of Ophthalmology, Medical College of Georgia at Augusta University 30912, Augusta, GA, USA.
| | - Jing Wang
- Department of Cellular Biology and Anatomy, Medical College of Georgia at Augusta University, Augusta, GA, USA; The James and Jean Culver Vision Discovery Institute, Augusta University, Augusta, GA, USA
| | - Xuezhi Cui
- Department of Cellular Biology and Anatomy, Medical College of Georgia at Augusta University, Augusta, GA, USA; The James and Jean Culver Vision Discovery Institute, Augusta University, Augusta, GA, USA
| | - Barbara A Mysona
- Department of Cellular Biology and Anatomy, Medical College of Georgia at Augusta University, Augusta, GA, USA; The James and Jean Culver Vision Discovery Institute, Augusta University, Augusta, GA, USA
| | - Jing Zhao
- The James and Jean Culver Vision Discovery Institute, Augusta University, Augusta, GA, USA; Department of Ophthalmology, Medical College of Georgia at Augusta University 30912, Augusta, GA, USA
| | - Kathryn E Bollinger
- Department of Cellular Biology and Anatomy, Medical College of Georgia at Augusta University, Augusta, GA, USA; The James and Jean Culver Vision Discovery Institute, Augusta University, Augusta, GA, USA; Department of Ophthalmology, Medical College of Georgia at Augusta University 30912, Augusta, GA, USA
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25
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Bergkemper M, Kronenberg E, Thum S, Börgel F, Daniliuc C, Schepmann D, Nieto FR, Brust P, Reinoso RF, Alvarez I, Wünsch B. Synthesis, Receptor Affinity, and Antiallodynic Activity of Spirocyclic σ Receptor Ligands with Exocyclic Amino Moiety. J Med Chem 2018; 61:9666-9690. [PMID: 30350997 DOI: 10.1021/acs.jmedchem.8b01183] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In order to detect novel σ receptor ligands, the rigid spiro[[2]benzopyran-1,1'-cyclohexan]-4'-one was connected with amino moieties derived from σ2 receptor preferring lead compounds resulting in mixtures of trans- and cis-configured amines 6, 18, and 27. In a four step synthesis the methyl acetals 6 were converted into fluoroethyl derivatives 13 and 30. The most promising σ2 receptor ligand is the methyl acetal 6a bearing a 2,4-dimethylbenzylamino moiety. The fluoroethyl derivatives 13c and 13d reveal high σ1 affinity but moderate selectivity over the σ2 subtype. In mice 13c and 13d showed antiallodynic activity that is stronger than that of the reference σ1 antagonist BD-1063 (34). Since the antiallodynic activity of 13c could only be partially reversed by the σ1 agonist PRE-084 (35), it is postulated that a second mechanism contributes to its overall antiallodynic effect. In contrast, the antiallodynic effect of its diastereomer 13d can be totally explained by a σ1 antagonism.
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Affiliation(s)
- Melanie Bergkemper
- Institut für Pharmazeutische und Medizinische Chemie der Universität Münster , Corrensstraße 48 , D-48149 Münster , Germany
| | - Elisabeth Kronenberg
- Institut für Pharmazeutische und Medizinische Chemie der Universität Münster , Corrensstraße 48 , D-48149 Münster , Germany
| | - Simone Thum
- Institut für Pharmazeutische und Medizinische Chemie der Universität Münster , Corrensstraße 48 , D-48149 Münster , Germany
| | - Frederik Börgel
- Institut für Pharmazeutische und Medizinische Chemie der Universität Münster , Corrensstraße 48 , D-48149 Münster , Germany
| | - Constantin Daniliuc
- Organisch-Chemisches Institut der Westfälischen Wilhelms-Universität Münster , Corrensstraße 40 , D-48149 Münster , Germany
| | - Dirk Schepmann
- Institut für Pharmazeutische und Medizinische Chemie der Universität Münster , Corrensstraße 48 , D-48149 Münster , Germany
| | - Francisco Rafael Nieto
- Department of Pharmacology and Institute of Neuroscience, School of Medicine and Biomedical Research Center , University of Granada , Avenida de la Investigación 11 , 18016 Granada , Spain
| | - Peter Brust
- Institut für Radiopharmazeutische Krebsforschung, Forschungsstelle Leipzig , Helmholtz-Zentrum Dresden-Rossendorf , Permoserstraße 15 , 04318 Leipzig , Germany
| | - Raquel F Reinoso
- Esteve Pharmaceuticals S.A , Baldiri Reixach 4-8 , 08028 Barcelona , Spain
| | - Inés Alvarez
- Esteve Pharmaceuticals S.A , Baldiri Reixach 4-8 , 08028 Barcelona , Spain
| | - Bernhard Wünsch
- Institut für Pharmazeutische und Medizinische Chemie der Universität Münster , Corrensstraße 48 , D-48149 Münster , Germany.,Cells-in-Motion Cluster of Excellence (EXC 1003-CiM) , Westfälische Wilhelms-Universität Münster , 48149 Münster , Germany
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26
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Imaging sigma receptors in the brain: New opportunities for diagnosis of Alzheimer's disease and therapeutic development. Neurosci Lett 2018; 691:3-10. [PMID: 30040970 DOI: 10.1016/j.neulet.2018.07.033] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Revised: 07/09/2018] [Accepted: 07/20/2018] [Indexed: 10/28/2022]
Abstract
The sigma-1 (σ1) receptor is a chaperone protein located on the mitochondria-associated membrane of the endoplasmic reticulum, while the sigma-2 receptor (σ2) is an endoplasmic reticulum-resident membrane protein. Recent evidence indicates that both of these receptors figure prominently in the pathophysiology of Alzheimer's disease (AD) and thus are targets for the development of novel, disease-modifying therapeutic strategies. Radioligand-based molecular imaging technique such as positron emission tomography (PET) imaging is a powerful tool for the investigation of protein target expression and function in living subjects. In this review, we survey the development of PET radioligands for the σ1 or σ2 receptors and assess their potential for human imaging applications. The availability of PET imaging with σ1 or σ2 receptor-specific radioligands in humans will allow the investigation of these receptors in vivo and lead to further understanding of their respective roles in AD pathogenesis and progression. Moreover, PET imaging can be used in target occupancy studies to assess target engagement and correlate receptor occupancy and therapeutic response of σ1 receptor agonists and σ2 receptor antagonists currently in clinical trials. It is expected that neuroimaging of σ1 and σ2 receptors in the brain will shed new light on AD pathophysiology and may provide us with new biomarkers for diagnosis of AD and efficacy monitoring of emerging AD therapeutic strategies.
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27
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Turnaturi R, Montenegro L, Marrazzo A, Parenti R, Pasquinucci L, Parenti C. Benzomorphan skeleton, a versatile scaffold for different targets: A comprehensive review. Eur J Med Chem 2018; 155:492-502. [PMID: 29908442 DOI: 10.1016/j.ejmech.2018.06.017] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Revised: 03/23/2018] [Accepted: 06/06/2018] [Indexed: 12/21/2022]
Abstract
Despite the fact that the benzomorphan skeleton has mainly been employed in medicinal chemistry for the development of opioid analgesics, it is a versatile structure. Its stereochemistry, as well as opportune modifications at the phenolic hydroxyl group and at the basic nitrogen, play a pivotal role addressing the benzomorphan-based compounds to a specific target. In this review, we describe the structure activity-relationships (SARs) of benzomorphan-based compounds acting at sigma 1 receptor (σ1R), sigma 2 receptor (σ2R), voltage-dependent sodium channel, N-Methyl-d-Aspartate (NMDA) receptor-channel complex and other targets. Collectively, the SARs data have highlighted that the benzomorphan nucleus could be regarded as a useful template for the synthesis of drug candidates for different targets.
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Affiliation(s)
- Rita Turnaturi
- Department of Drug Sciences, Medicinal Chemistry Section, University of Catania, Viale A. Doria, 6, 95100, Catania, Italy.
| | - Lucia Montenegro
- Department of Drug Sciences, Pharmaceutical Technology Section, University of Catania, Viale A. Doria 6, 95125, Catania, Italy
| | - Agostino Marrazzo
- Department of Drug Sciences, Medicinal Chemistry Section, University of Catania, Viale A. Doria, 6, 95100, Catania, Italy
| | - Rosalba Parenti
- Department of Biomedical and Biotechnological Sciences, Physiology Section, University of Catania, Catania, Italy
| | - Lorella Pasquinucci
- Department of Drug Sciences, Medicinal Chemistry Section, University of Catania, Viale A. Doria, 6, 95100, Catania, Italy
| | - Carmela Parenti
- Department of Drug Sciences, Pharmacology Section, University of Catania, Viale A. Doria, 6, 95100, Catania, Italy
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28
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Franchini S, Sorbi C, Battisti UM, Tait A, Bencheva LI, Cichero E, Fossa P, Cilia A, Prezzavento O, Ronsisvalle S, Aricò G, Benassi L, Vaschieri C, Azzoni P, Magnoni C, Brasili L. Structure-Activity Relationships within a Series of σ1
and σ2
Receptor Ligands: Identification of a σ2
Receptor Agonist (BS148) with Selective Toxicity against Metastatic Melanoma. ChemMedChem 2017; 12:1893-1905. [DOI: 10.1002/cmdc.201700427] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Revised: 09/20/2017] [Indexed: 11/09/2022]
Affiliation(s)
- Silvia Franchini
- Dipartimento di Scienze della Vita; Università degli Studi di Modena e Reggio Emilia; Via Campi 103 41125 Modena Italy
| | - Claudia Sorbi
- Dipartimento di Scienze della Vita; Università degli Studi di Modena e Reggio Emilia; Via Campi 103 41125 Modena Italy
| | - Umberto Maria Battisti
- Dipartimento di Scienze della Vita; Università degli Studi di Modena e Reggio Emilia; Via Campi 103 41125 Modena Italy
| | - Annalisa Tait
- Dipartimento di Scienze della Vita; Università degli Studi di Modena e Reggio Emilia; Via Campi 103 41125 Modena Italy
| | - Leda Ivanova Bencheva
- Dipartimento di Scienze della Vita; Università degli Studi di Modena e Reggio Emilia; Via Campi 103 41125 Modena Italy
| | - Elena Cichero
- Dipartimento di Farmacia; Università degli Studi di Genova; Viale Benedetto XV 3 16132 Genova Italy
| | - Paola Fossa
- Dipartimento di Farmacia; Università degli Studi di Genova; Viale Benedetto XV 3 16132 Genova Italy
| | - Antonio Cilia
- Divisione Ricerca e Sviluppo; Recordati S.p.A.; Via Civitali 1 20148 Milano Italy
| | - Orazio Prezzavento
- Dipartimento di Scienze del Farmaco; Università degli Studi di Catania; Viale Andrea Doria 6 95125 Catania Italy
| | - Simone Ronsisvalle
- Dipartimento di Scienze del Farmaco; Università degli Studi di Catania; Viale Andrea Doria 6 95125 Catania Italy
| | - Giuseppina Aricò
- Dipartimento di Scienze del Farmaco; Università degli Studi di Catania; Viale Andrea Doria 6 95125 Catania Italy
| | - Luisa Benassi
- Dipartimento Chirurgico, Medico, Odontoiatrico e di Scienze Morfologiche con interesse Trapiantologico, Oncologico e di Medicina Rigenerativa; Università degli Studi di Modena e Reggio Emilia; via del Pozzo 71 41124 Modena Italy
| | - Cristina Vaschieri
- Dipartimento Chirurgico, Medico, Odontoiatrico e di Scienze Morfologiche con interesse Trapiantologico, Oncologico e di Medicina Rigenerativa; Università degli Studi di Modena e Reggio Emilia; via del Pozzo 71 41124 Modena Italy
| | - Paola Azzoni
- Dipartimento Chirurgico, Medico, Odontoiatrico e di Scienze Morfologiche con interesse Trapiantologico, Oncologico e di Medicina Rigenerativa; Università degli Studi di Modena e Reggio Emilia; via del Pozzo 71 41124 Modena Italy
| | - Cristina Magnoni
- Dipartimento Chirurgico, Medico, Odontoiatrico e di Scienze Morfologiche con interesse Trapiantologico, Oncologico e di Medicina Rigenerativa; Università degli Studi di Modena e Reggio Emilia; via del Pozzo 71 41124 Modena Italy
| | - Livio Brasili
- Dipartimento di Scienze della Vita; Università degli Studi di Modena e Reggio Emilia; Via Campi 103 41125 Modena Italy
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29
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Georgiadis MO, Karoutzou O, Foscolos AS, Papanastasiou I. Sigma Receptor (σR) Ligands with Antiproliferative and Anticancer Activity. Molecules 2017; 22:E1408. [PMID: 28841173 PMCID: PMC6151391 DOI: 10.3390/molecules22091408] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Revised: 08/22/2017] [Accepted: 08/23/2017] [Indexed: 01/01/2023] Open
Abstract
Sigma receptor (σR) ligands have proven to be useful as cancer diagnostics and anticancer therapeutics and their ligands have been developed as molecular probes in oncology. Moreover, various σR ligands generate cancer cell death in vitro and in vivo. These σR ligands have exhibited promising results against numerous human and rodent cancers and are investigated under preclinical and clinical study trials, indicating a new category of drugs in cancer therapy.
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Affiliation(s)
- Markos-Orestis Georgiadis
- School of Health Sciences, Department of Pharmacy, Division of Pharmaceutical Chemistry, National and Kapodistrian University of Athens, Panepistimioupoli-Zografou, 15784 Athens, Greece.
| | - Olga Karoutzou
- School of Health Sciences, Department of Pharmacy, Division of Pharmaceutical Chemistry, National and Kapodistrian University of Athens, Panepistimioupoli-Zografou, 15784 Athens, Greece.
| | - Angeliki-Sofia Foscolos
- School of Health Sciences, Department of Pharmacy, Division of Pharmaceutical Chemistry, National and Kapodistrian University of Athens, Panepistimioupoli-Zografou, 15784 Athens, Greece.
| | - Ioannis Papanastasiou
- School of Health Sciences, Department of Pharmacy, Division of Pharmaceutical Chemistry, National and Kapodistrian University of Athens, Panepistimioupoli-Zografou, 15784 Athens, Greece.
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30
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Donnier-Maréchal M, Carato P, Larchanché PE, Ravez S, Boulahjar R, Barczyk A, Oxombre B, Vermersch P, Melnyk P. Synthesis and pharmacological evaluation of benzamide derivatives as potent and selective sigma-1 protein ligands. Eur J Med Chem 2017; 138:964-978. [PMID: 28756263 DOI: 10.1016/j.ejmech.2017.07.014] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Revised: 05/22/2017] [Accepted: 07/10/2017] [Indexed: 02/08/2023]
Abstract
A series of novel benzamide-derived compounds was designed, synthesized and pharmacologically evaluated. Among all 37 synthesized compounds, two series were developed with the modulation of the nature, the position of atoms or groups on the benzamide scaffold, but also the nature of the amine group separated from the benzamide with 2, 3 or 4 methylene groups. In vitro competition binding assays against sigma proteins (sigma-1 S1R and sigma-2 S2R) revealed that most of them conferred S2R/S1R selectivity toward without cytotoxic effects on SY5Y cells, especially with the first series with compounds 7a-z. Some selected compounds were also evaluated for their agonist and antagonist activities on a panel of 40 receptors. Results showed the importance of the nature and the position with halogeno atom on the benzamide scaffold, the length chain but also the contribution of the hydrophobic part on the amine group. Among them, compounds 7i, w, y with Cl, CN or NO2 groups at the 4-position of the benzamide scaffold showed excellent affinity for S1R (Ki = 1.2-3.6 nM), selectivity for S2R (Ki up to 1400 nM) and high selectivity index (IC50(SY5Y)/Ki(S1R) ratio from 28 000 to 83 000). Futhermore, these compounds presented an excellent safety profile over 40 other receptors. These derivatives will be selected for further biological investigations.
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Affiliation(s)
- Marion Donnier-Maréchal
- Univ. Lille, Inserm, CHU Lille, UMR-S 1172 - JPArc - Centre de Recherche Jean-Pierre AUBERT Neurosciences et Cancer, F-59000 Lille, France.
| | - Pascal Carato
- Univ. Lille, Inserm, CHU Lille, UMR-S 1172 - JPArc - Centre de Recherche Jean-Pierre AUBERT Neurosciences et Cancer, F-59000 Lille, France.
| | - Paul-Emmanuel Larchanché
- Univ. Lille, Inserm, CHU Lille, UMR-S 1172 - JPArc - Centre de Recherche Jean-Pierre AUBERT Neurosciences et Cancer, F-59000 Lille, France.
| | - Séverine Ravez
- Univ. Lille, Inserm, CHU Lille, UMR-S 1172 - JPArc - Centre de Recherche Jean-Pierre AUBERT Neurosciences et Cancer, F-59000 Lille, France.
| | - Rajaa Boulahjar
- Univ. Lille, Inserm, CHU Lille, UMR-S 1172 - JPArc - Centre de Recherche Jean-Pierre AUBERT Neurosciences et Cancer, F-59000 Lille, France.
| | - Amélie Barczyk
- Univ. Lille, Inserm, CHU Lille, U995 - LIRIC - Lille Inflammation Research International Center, F-59000 Lille, France.
| | - Bénédicte Oxombre
- Univ. Lille, Inserm, CHU Lille, U995 - LIRIC - Lille Inflammation Research International Center, F-59000 Lille, France.
| | - Patrick Vermersch
- Univ. Lille, Inserm, CHU Lille, U995 - LIRIC - Lille Inflammation Research International Center, F-59000 Lille, France.
| | - Patricia Melnyk
- Univ. Lille, Inserm, CHU Lille, UMR-S 1172 - JPArc - Centre de Recherche Jean-Pierre AUBERT Neurosciences et Cancer, F-59000 Lille, France.
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Zhang K, Zhao Z, Lan L, Wei X, Wang L, Liu X, Yan H, Zheng J. Sigma-1 Receptor Plays a Negative Modulation on N-type Calcium Channel. Front Pharmacol 2017; 8:302. [PMID: 28603497 PMCID: PMC5445107 DOI: 10.3389/fphar.2017.00302] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Accepted: 05/10/2017] [Indexed: 12/30/2022] Open
Abstract
The sigma-1 receptor is a 223 amino acids molecular chaperone with a single transmembrane domain. It is resident to eukaryotic mitochondrial-associated endoplasmic reticulum and plasma membranes. By chaperone-mediated interactions with ion channels, G-protein coupled receptors and cell-signaling molecules, the sigma-1 receptor performs broad physiological and pharmacological functions. Despite sigma-1 receptors have been confirmed to regulate various types of ion channels, the relationship between the sigma-1 receptor and N-type Ca2+ channel is still unclear. Considering both sigma-1 receptors and N-type Ca2+ channels are involved in intracellular calcium homeostasis and neurotransmission, we undertake studies to explore the possible interaction between these two proteins. In the experiment, we confirmed the expression of the sigma-1 receptors and the N-type calcium channels in the cholinergic interneurons (ChIs) in rat striatum by using single-cell reverse transcription-polymerase chain reaction (scRT-PCR) and immunofluorescence staining. N-type Ca2+ currents recorded from ChIs in the brain slice of rat striatum was depressed when sigma-1 receptor agonists (SKF-10047 and Pre-084) were administrated. The inhibition was completely abolished by sigma-1 receptor antagonist (BD-1063). Co-expression of the sigma-1 receptors and the N-type calcium channels in Xenopus oocytes presented a decrease of N-type Ca2+ current amplitude with an increase of sigma-1 receptor expression. SKF-10047 could further depress N-type Ca2+ currents recorded from oocytes. The fluorescence resonance energy transfer (FRET) assays and co-immunoprecipitation (Co-IP) demonstrated that sigma-1 receptors and N-type Ca2+ channels formed a protein complex when they were co-expressed in HEK-293T (Human Embryonic Kidney -293T) cells. Our results revealed that the sigma-1 receptors played a negative modulation on N-type Ca2+ channels. The mechanism for the inhibition of sigma-1 receptors on N-type Ca2+ channels probably involved a chaperone-mediated direct interaction and agonist-induced conformational changes in the receptor-channel complexes on the cell surface.
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Affiliation(s)
- Kang Zhang
- State Key Laboratory of Toxicology and Medical Countermeasures, Beijing Key Laboratory of Neuropsychopharmacology, Department of Biochemical Pharmacology, Beijing Institute of Pharmacology and ToxicologyBeijing, China
| | - Zhe Zhao
- Department of Neurobiology, Beijing Institute of Basic Medical SciencesBeijing, China
| | - Liting Lan
- State Key Laboratory of Toxicology and Medical Countermeasures, Beijing Key Laboratory of Neuropsychopharmacology, Department of Biochemical Pharmacology, Beijing Institute of Pharmacology and ToxicologyBeijing, China
| | - Xiaoli Wei
- State Key Laboratory of Toxicology and Medical Countermeasures, Beijing Key Laboratory of Neuropsychopharmacology, Department of Biochemical Pharmacology, Beijing Institute of Pharmacology and ToxicologyBeijing, China
| | - Liyun Wang
- State Key Laboratory of Toxicology and Medical Countermeasures, Beijing Key Laboratory of Neuropsychopharmacology, Department of Biochemical Pharmacology, Beijing Institute of Pharmacology and ToxicologyBeijing, China
| | - Xiaoyan Liu
- State Key Laboratory of Toxicology and Medical Countermeasures, Beijing Key Laboratory of Neuropsychopharmacology, Department of Biochemical Pharmacology, Beijing Institute of Pharmacology and ToxicologyBeijing, China
| | - Haitao Yan
- State Key Laboratory of Toxicology and Medical Countermeasures, Beijing Key Laboratory of Neuropsychopharmacology, Department of Biochemical Pharmacology, Beijing Institute of Pharmacology and ToxicologyBeijing, China
| | - Jianquan Zheng
- State Key Laboratory of Toxicology and Medical Countermeasures, Beijing Key Laboratory of Neuropsychopharmacology, Department of Biochemical Pharmacology, Beijing Institute of Pharmacology and ToxicologyBeijing, China
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Pan L, Pasternak DA, Xu J, Xu M, Lu Z, Pasternak GW, Pan YX. Isolation and characterization of alternatively spliced variants of the mouse sigma1 receptor gene, Sigmar1. PLoS One 2017; 12:e0174694. [PMID: 28350844 PMCID: PMC5370144 DOI: 10.1371/journal.pone.0174694] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2016] [Accepted: 03/13/2017] [Indexed: 12/27/2022] Open
Abstract
The sigma1 receptor acts as a chaperone at the endoplasmic reticulum, associates with multiple proteins in various cellular systems, and involves in a number of diseases, such as addiction, pain, cancer and psychiatric disorders. The sigma1 receptor is encoded by the single copy SIGMAR1 gene. The current study identifies five alternatively spliced variants of the mouse sigma1 receptor gene using a polymerase chain reaction cloning approach. All the splice variants are generated by exon skipping or alternative 3' or 5' splicing, producing the truncated sigma1 receptor. Similar alternative splicing has been observed in the human SIGMAR1 gene based on the molecular cloning or genome sequence prediction, suggesting conservation of alternative splicing of SIGMAR1 gene. Using quantitative polymerase chain reactions, we demonstrate differential expression of several splice variants in mouse tissues and brain regions. When expressed in HEK293 cells, all the splice variants fail to bind sigma ligands, implicating that each truncated region in these splice variants is important for ligand binding. However, co-immunoprecipitation (Co-IP) study in HEK293 cells co-transfected with tagged constructs reveals that all the splice variants maintain their ability to physically associate with a mu opioid receptor (mMOR-1), providing useful information to correlate the motifs/sequences necessary for their physical association. Furthermore, a competition Co-IP study showed that all the variants can disrupt in a dose-dependent manner the dimerization of the original sigma1 receptor with mMOR-1, suggesting a potential dominant negative function and providing significant insights into their function.
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Affiliation(s)
- Ling Pan
- Department of Neurology and the Molecular Pharmacology Program, Memorial Sloan-Kettering Cancer Center, New York, New York, United States of America
| | - David A. Pasternak
- Department of Neurology and the Molecular Pharmacology Program, Memorial Sloan-Kettering Cancer Center, New York, New York, United States of America
| | - Jin Xu
- Department of Neurology and the Molecular Pharmacology Program, Memorial Sloan-Kettering Cancer Center, New York, New York, United States of America
| | - Mingming Xu
- Department of Neurology and the Molecular Pharmacology Program, Memorial Sloan-Kettering Cancer Center, New York, New York, United States of America
| | - Zhigang Lu
- Key Laboratory of Acupuncture and Medicine Research of Ministry of Education, Nanjing University of Chinese Medicine, Nanjing, Jianshu, China
- First Clinical Medical College, Nanjing University of Chinese Medicine, Nanjing, Jiangshu, China
| | - Gavril W. Pasternak
- Department of Neurology and the Molecular Pharmacology Program, Memorial Sloan-Kettering Cancer Center, New York, New York, United States of America
| | - Ying-Xian Pan
- Department of Neurology and the Molecular Pharmacology Program, Memorial Sloan-Kettering Cancer Center, New York, New York, United States of America
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Mandelli L, Wang SM, Han C, Lee SJ, Patkar AA, Masand PS, Pae CU, Serretti A. The Impact of a Single Nucleotide Polymorphism in SIGMAR1 on Depressive Symptoms in Major Depressive Disorder and Bipolar Disorder. Adv Ther 2017; 34:713-724. [PMID: 28144920 DOI: 10.1007/s12325-017-0482-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2016] [Indexed: 10/20/2022]
Abstract
INTRODUCTION Ample evidence suggested a role of sigma-1 receptor in affective disorders since the interaction of numerous antidepressants with sigma receptors was discovered. A recent study on Japanese subjects found a genetic variant within the encoding gene SIGMAR1 (rs1800866A>C) associated with major depressive disorder (MDD). We aimed to evaluate the same polymorphism in both MDD and bipolar disorder (BD) as well as its relationship to response to treatment with antidepressants and mood stabilizers. METHODS A total of 238 MDD patients treated for an acute episode of depression, 132 BD patients in treatment with mood stabilizers for a manic or mixed episode, and 324 controls were genotyped for rs1800866. At discharge, response to treatments was evaluated in MDD and BD patients by the Hamilton Rating Scale for Depression (HRSD) and the Young Mania Rating Score (YMRS), respectively. RESULTS In our Korean sample, allele frequencies were different from those reported in other Asian and non-Asian populations. The CC genotype was associated with BD and, as a trend, with MDD. No significant effect was observed on response to antidepressants in MDD or mood stabilizers in BD, although the CC genotype was more frequent among BD patients experiencing a mixed episode. CONCLUSION The present findings are the first to propose the putative role of genetic variants within SIGMAR1 and sigma-1 receptor in BD. Sigma-1 receptor can modulate a number of central neurotransmitter systems as well as some other signaling pathways (e.g., neurotrophin and growth factor signaling) which are seemingly involved in BD and other mood disorders.
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Affiliation(s)
- Laura Mandelli
- Department of Biomedical and NeuroMotor Sciences, Institute of Psychiatry, University of Bologna, Bologna, Italy
| | - Sheng-Min Wang
- Department of Psychiatry, The Catholic University of Korea College of Medicine, Seoul, Republic of Korea
- International Health Care Center, Seoul St. Mary's Hospital, The Catholic University of Korea College of Medicine, Seoul, Korea
| | - Changsu Han
- Department of Psychiatry, Korea University, College of Medicine, Seoul, Republic of Korea
| | - Soo-Jung Lee
- Department of Psychiatry, The Catholic University of Korea College of Medicine, Seoul, Republic of Korea
| | - Ashwin A Patkar
- Department of Psychiatry and Behavioural Sciences, Duke University Medical Center, Durham, NC, USA
| | - Prakash S Masand
- Global Medical Education, New York, NY, USA
- Academic Medicine Education Institute, Duke-NUS Medical School, Singapore, Singapore
| | - Chi-Un Pae
- Department of Psychiatry, The Catholic University of Korea College of Medicine, Seoul, Republic of Korea.
- Department of Psychiatry and Behavioural Sciences, Duke University Medical Center, Durham, NC, USA.
| | - Alessandro Serretti
- Department of Biomedical and NeuroMotor Sciences, Institute of Psychiatry, University of Bologna, Bologna, Italy
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Dasargyri A, Kümin CD, Leroux JC. Targeting Nanocarriers with Anisamide: Fact or Artifact? ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2017; 29:1603451. [PMID: 27885719 DOI: 10.1002/adma.201603451] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Revised: 09/08/2016] [Indexed: 05/19/2023]
Abstract
Encapsulating chemotherapeutics in nanoparticles can reduce the side effects of intravenous administration and improve their antitumor efficacy. Additionally, surface decoration of the nanocarriers with tumor-targeting ligands may enhance their specificity for cancer cells overexpressing the corresponding ligand-binding counterpart. The focus here is on anisamide, a low-molecular-weight benzamide derivative used as a tumor-directing moiety in functionalized nanosystems, based on its alleged interaction with Sigma receptors. The scintigraphic agents that initially inspired the use of anisamide for tumor targeting are described, and the published anisamide-tethered nanocarrier formulations are reviewed, together with a critical overview of the ligand's tumor-targeting properties. Moreover, anisamide's putative but dubious cellular target, the Sigma-1 receptor, is discussed with regard to its subcellular localization and implications in cancer. Data from in vivo studies reveal that the effect of anisamide on the antitumor efficacy of the decorated nanosystems varies considerably among the published reports. Together with the evidence questioning the interaction of anisamide with the Sigma receptors, the variability of anisamide's effect on the tumor deposition and the antitumor efficacy of the decorated drug carriers calls into question the extent of the ligand's tumor-targeting effect. Further research is necessary to elucidate the ligand's utility in tumor targeting.
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Affiliation(s)
- Athanasia Dasargyri
- Department of Chemistry and Applied Biosciences, Institute of Pharmaceutical Sciences, Swiss Federal Institute of Technology Zurich (ETHZ), Zurich, 8093, Switzerland
| | - Carole D Kümin
- Department of Chemistry and Applied Biosciences, Institute of Pharmaceutical Sciences, Swiss Federal Institute of Technology Zurich (ETHZ), Zurich, 8093, Switzerland
| | - Jean-Christophe Leroux
- Department of Chemistry and Applied Biosciences, Institute of Pharmaceutical Sciences, Swiss Federal Institute of Technology Zurich (ETHZ), Zurich, 8093, Switzerland
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Pasternak GW. Allosteric Modulation of Opioid G-Protein Coupled Receptors by Sigma 1 Receptors. Handb Exp Pharmacol 2017; 244:163-175. [PMID: 28667477 DOI: 10.1007/164_2017_34] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Since their proposal in 1976, the concept of sigma1 receptors has been continually evolving. Initially thought to be a member of the opioid receptor family, molecular studies have now identified its genes and established its structure crystallographically. Much effort has now revealed its importance as a chaperone in the endoplasmic reticulum, but its functions extend beyond this. Sigma1 receptors have been associated with a host of signaling systems. Evidence over the past 20 years has established the modulatory effects of sigma1 ligands on opioid systems. Despite their inability to bind directly to opioid receptors, sigma1 ligands can modulate opioid analgesia in vivo and signal transduction mechanisms in vitro. Furthermore, sigma1 receptors can physically associate with GPCRs. Together, these findings show that sigma1 ligands can function as allosteric modulators of GPCR function through their association with the sigma1 receptors, which are in direct physical association with opioid receptors, members of the G-protein coupled family of receptors.
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Affiliation(s)
- Gavril W Pasternak
- Department of Neurology and Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, NY, 10021, USA.
- Department of Neurology, Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, 1275 York Ave, New York, NY, 10065, USA.
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36
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Alon A, Schmidt H, Zheng S, Kruse AC. Structural Perspectives on Sigma-1 Receptor Function. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 964:5-13. [PMID: 28315261 DOI: 10.1007/978-3-319-50174-1_2] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The sigma-1 receptor is an enigmatic ER-resident transmembrane protein linked to a variety of human diseases. Although the receptor was first cloned 20 years ago, the molecular structure of the protein and the mechanistic basis for its interaction with drug-like small molecules have remained unclear until recently. The determination of the first crystal structure of human sigma-1 offered the first detailed views of the sigma-1 architecture, and revealed an unusual overall fold with a single transmembrane helix in each protomer. The structure shows an overall trimeric receptor arrangement, and each protomer binds a single ligand molecule at the center of its carboxy-terminal domain. These results offer detailed molecular views of receptor structure, oligomerization, and ligand recognition, providing a framework for the next era of sigma-1 research.
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Affiliation(s)
- Assaf Alon
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, 02115, USA
| | - Hayden Schmidt
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, 02115, USA
| | - Sanduo Zheng
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, 02115, USA
| | - Andrew C Kruse
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, 02115, USA.
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37
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Zeng C, McDonald ES, Mach RH. Molecular Probes for Imaging the Sigma-2 Receptor: In Vitro and In Vivo Imaging Studies. Handb Exp Pharmacol 2017; 244:309-330. [PMID: 28176045 DOI: 10.1007/164_2016_96] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The sigma-2 (σ2) receptor has been validated as a biomarker of the proliferative status of solid tumors. Therefore, radiotracers having a high affinity and high selectivity for σ2 receptors have the potential to assess the proliferative status of human tumors using noninvasive imaging techniques such as Positron Emission Tomography (PET). Since the σ2 receptor has not been cloned, the current knowledge of this receptor has relied on receptor binding studies with the radiolabeled probes and investigation of the effects of the σ2 receptor ligands on tumor cells. The development of the σ2 selective fluorescent probes has proven to be useful for studying subcellular localization and biological functions of the σ2 receptor, for revealing pharmacological properties of the σ2 receptor ligands, and for imaging cell proliferation. Preliminary clinical imaging studies with [18F]ISO-1, a σ2 receptor probe, have shown promising results in cancer patients. However, the full utility of imaging the σ2 receptor status of solid tumors in the diagnosis and prediction of cancer therapeutic response will rely on elucidation of the functional role of this protein in normal and tumor cell biology.
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Affiliation(s)
- Chenbo Zeng
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Elizabeth S McDonald
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Robert H Mach
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA.
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Abstract
Sigma1 (also known as this sigma-1 receptor) is an unusual and enigmatic transmembrane protein implicated in a diverse array of biological processes ranging from neurodegenerative disease to cancer. Despite decades of research, the molecular architecture of Sigma1 is only beginning to become clear. Recent work has established that Sigma1 is an oligomer, and crystallographic studies have now offered the first high-resolution views of its molecular structure. For the first time, these results provide a detailed framework to understand mutagenesis data and the molecular pharmacology of Sigma1 ligands. Structural data also raise new questions surrounding the mechanisms of ligand activity and the molecular basis for interactions between Sigma1 and other proteins. As Sigma1 research enters the structural era, the field is poised for new discoveries and reevaluation of old data and old models.
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Affiliation(s)
- Andrew Kruse
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Seeley G. Mudd Building, 250 Longwood Ave., Boston, MA, 02115, USA.
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Abstract
Sigma1 (also known as sigma-1 receptor, Sig1R, σ1 receptor) is a unique pharmacologically regulated integral membrane chaperone or scaffolding protein. The majority of publications on the subject have focused on the neuropharmacology of Sigma1. However, a number of publications have also suggested a role for Sigma1 in cancer. Although there is currently no clinically used anti-cancer drug that targets Sigma1, a growing body of evidence supports the potential of Sigma1 ligands as therapeutic agents to treat cancer. In preclinical models, compounds with affinity for Sigma1 have been reported to inhibit cancer cell proliferation and survival, cell adhesion and migration, tumor growth, to alleviate cancer-associated pain, and to have immunomodulatory properties. This review will highlight that although the literature supports a role for Sigma1 in cancer, several fundamental questions regarding drug mechanism of action and the physiological relevance of aberrant SIGMAR1 transcript and Sigma1 protein expression in certain cancers remain unanswered or only partially answered. However, emerging lines of evidence suggest that Sigma1 is a component of the cancer cell support machinery, that it facilitates protein interaction networks, that it allosterically modulates the activity of its associated proteins, and that Sigma1 is a selectively multifunctional drug target.
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Affiliation(s)
- Felix J Kim
- Department of Pharmacology and Physiology, Drexel University College of Medicine, 245 North 15th Street, Philadelphia, PA, USA.
- Sidney Kimmel Cancer Center, Philadelphia, PA, USA.
| | - Christina M Maher
- Department of Pharmacology and Physiology, Drexel University College of Medicine, 245 North 15th Street, Philadelphia, PA, USA
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Wang J, Cui X, Roon P, Saul A, Smith SB. The Role of Sigma1R in Mammalian Retina. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 964:267-284. [PMID: 28315277 DOI: 10.1007/978-3-319-50174-1_18] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
This review article focuses on studies of Sigma 1 Receptor (Sigma1R) and retina . It provides a brief overview of the earliest pharmacological studies performed in the late 1990s that provided evidence of the presence of Sigma1R in various ocular tissues. It then describes work from a number of labs concerning the location of Sigma1R in several retinal cell types including ganglion, Müller glia , and photoreceptors . The role of Sigma1R ligands in retinal neuroprotection is emphasized. Early studies performed in vitro clearly showed that targeting Sigma1R could attenuate stress-induced retinal cell loss. These studies were followed by in vivo experiments. Data about the usefulness of targeting Sigma1R to prevent ganglion cell loss associated with diabetic retinopathy are reviewed. Mechanisms of Sigma1R-mediated retinal neuroprotection involving Müller cells , especially in modulating oxidative stress are described along with information about the retinal phenotype of mice lacking Sigma1R (Sigma1R -/- mice). The retina develops normally in Sigma1R -/- mice, but after many months there is evidence of apoptosis in the optic nerve head, decreased ganglion cell function and eventual loss of these cells. Additional studies using the Sigma1R -/- mice provide strong evidence that in the retina, Sigma1R plays a key role in modulating cellular stress. Recent work has shown that targeting Sigma1R may extend beyond protection of ganglion cells to include photoreceptor cell degeneration as well.
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Affiliation(s)
- Jing Wang
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, 1120 15th Street, CB 1114, Augusta, GA, 30912-2000, USA
- The James and Jean Culver Vision Discovery Institute, Augusta University, Augusta, GA, USA
| | - Xuezhi Cui
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, 1120 15th Street, CB 1114, Augusta, GA, 30912-2000, USA
- The James and Jean Culver Vision Discovery Institute, Augusta University, Augusta, GA, USA
| | - Penny Roon
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, 1120 15th Street, CB 1114, Augusta, GA, 30912-2000, USA
| | - Alan Saul
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, 1120 15th Street, CB 1114, Augusta, GA, 30912-2000, USA
- The James and Jean Culver Vision Discovery Institute, Augusta University, Augusta, GA, USA
| | - Sylvia B Smith
- Departments of Cellular Biology and Anatomy and Ophthalmology and the James and Jean Culver Vision Discovery Institute, Medical College of Georgia at Augusta University, Augusta, GA, 30912, USA.
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Rossi D, Rui M, Di Giacomo M, Schepmann D, Wünsch B, Monteleone S, Liedl KR, Collina S. Gaining in pan-affinity towards sigma 1 and sigma 2 receptors. SAR studies on arylalkylamines. Bioorg Med Chem 2017; 25:11-19. [PMID: 27838169 DOI: 10.1016/j.bmc.2016.10.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Revised: 09/30/2016] [Accepted: 10/06/2016] [Indexed: 11/15/2022]
Abstract
Sigma Receptor (SR) modulators are involved in different signal transduction pathways, representing important pharmacological/therapeutic tools in several pathological conditions, such as neurodegenerative diseases and cancers. To this purpose, numerous compounds have been developed in order to target selectively one of the two subtypes (S1R and S2R) as chemotherapeutic agent. However, experiments have also shown that ligands which are able to bind both SR subtypes can be useful for the diagnosis and/or the treatment of cancers. Therefore, the discovery of compounds with good affinity towards both S1R and S2R ('pan-modulators') is also of great interest and still represents a challenge up to now. For this reason, we synthesized novel arylalkylamines with the aim to obtain compounds with S1R and S2R affinity in the nM range and, by modeling quantitative structure-activity relationships (QSARs), we identified the essential structural features to obtain promising pan-compounds.
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Affiliation(s)
- Daniela Rossi
- Department of Drug Sciences, Medicinal Chemistry and Pharmaceutical Technology Section, University of Pavia, Viale Taramelli 12, 27100 Pavia, Italy
| | - Marta Rui
- Department of Drug Sciences, Medicinal Chemistry and Pharmaceutical Technology Section, University of Pavia, Viale Taramelli 12, 27100 Pavia, Italy
| | - Marcello Di Giacomo
- Department of Drug Sciences, Medicinal Chemistry and Pharmaceutical Technology Section, University of Pavia, Viale Taramelli 12, 27100 Pavia, Italy
| | - Dirk Schepmann
- Institute of Pharmaceutical and Medicinal Chemistry, University of Muenster, Correnstrasse 48, 48149 Muenster, Germany
| | - Bernhard Wünsch
- Institute of Pharmaceutical and Medicinal Chemistry, University of Muenster, Correnstrasse 48, 48149 Muenster, Germany
| | - Stefania Monteleone
- Institute of General, Inorganic and Theoretical Chemistry, Center of Molecular Biosciences, University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Klaus R Liedl
- Institute of General, Inorganic and Theoretical Chemistry, Center of Molecular Biosciences, University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Simona Collina
- Department of Drug Sciences, Medicinal Chemistry and Pharmaceutical Technology Section, University of Pavia, Viale Taramelli 12, 27100 Pavia, Italy.
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Abstract
There is a critical need for new analgesics acting through new mechanisms of action, which could increase the efficacy respect to existing therapies and/or reduce their unwanted effects. Current preclinical evidence supports the modulatory role of the sigma-1 receptor (σ1R) in nociception, mainly based on the pain-attenuated phenotype of σ1R knockout mice and on the antinociceptive effect exerted by σ1R antagonists on pain of different etiology, very consistently in neuropathic pain, but also in nociceptive, inflammatory, and visceral pain. σ1R is highly expressed in different pain areas of the CNS and the periphery, particularly dorsal root ganglia (DRG), and interacts and modulates the functionality of different receptors and ion channels. Accordingly, antinociceptive effects of σ1R antagonists both acting alone and in combination with other analgesics have been reported at both central and peripheral sites. At the central level, behavioral, electrophysiological, neurochemical, and molecular findings support a role for σ1R antagonists in inhibiting augmented excitability secondary to sustained afferent input. Moreover, the involvement of σ1R in mechanisms regulating pain at the periphery has been recently confirmed. Unlike opioids, σ1R antagonists do not modify normal sensory mechanical and thermal sensitivity thresholds but they exert antihypersensitivity effects (antihyperalgesic and antiallodynic) in sensitizing conditions, enabling the reversal of nociceptive thresholds back to normal values. These are distinctive features allowing σ1R antagonists to exert a modulatory effect specifically in pathophysiological conditions such as chronic pain.
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Affiliation(s)
- Manuel Merlos
- Drug Discovery and Preclinical Development, ESTEVE, Barcelona, Spain
| | - Luz Romero
- Drug Discovery and Preclinical Development, ESTEVE, Barcelona, Spain
| | - Daniel Zamanillo
- Drug Discovery and Preclinical Development, ESTEVE, Barcelona, Spain
| | | | - José Miguel Vela
- Drug Discovery and Preclinical Development, ESTEVE, Barcelona, Spain.
- Parc Científic de Barcelona, Baldiri Reixac 4-8, 08028, Barcelona, Spain.
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Mavlyutov TA, Duellman T, Kim HT, Epstein ML, Leese C, Davletov BA, Yang J. Sigma-1 receptor expression in the dorsal root ganglion: Reexamination using a highly specific antibody. Neuroscience 2016; 331:148-57. [PMID: 27339730 PMCID: PMC5047027 DOI: 10.1016/j.neuroscience.2016.06.030] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Revised: 06/15/2016] [Accepted: 06/16/2016] [Indexed: 02/06/2023]
Abstract
Sigma-1 receptor (S1R) is a unique pluripotent modulator of living systems and has been reported to be associated with a number of neurological diseases including pathological pain. Intrathecal administration of S1R antagonists attenuates the pain behavior of rodents in both inflammatory and neuropathic pain models. However, the S1R localization in the spinal cord shows a selective ventral horn motor neuron distribution, suggesting the high likelihood of S1R in the dorsal root ganglion (DRG) mediating the pain relief by intrathecally administered drugs. Since primary afferents are the major component in the pain pathway, we examined the mouse and rat DRGs for the presence of the S1R. At both mRNA and protein levels, quantitative RT-PCR (qRT-PCR) and Western confirmed that the DRG contains greater S1R expression in comparison to spinal cord, cortex, or lung but less than liver. Using a custom-made highly specific antibody, we demonstrated the presence of a strong S1R immuno-fluorescence in all rat and mouse DRG neurons co-localizing with the Neuron-Specific Enolase (NSE) marker, but not in neural processes or GFAP-positive glial satellite cells. In addition, S1R was absent in afferent terminals in the skin and in the dorsal horn of the spinal cord. Using immuno-electron microscopy, we showed that S1R is detected in the nuclear envelope and endoplasmic reticulum (ER) of DRG cells. In contrast to other cells, S1R is also located directly at the plasma membrane of the DRG neurons. The presence of S1R in the nuclear envelope of all DRG neurons suggests an exciting potential role of S1R as a regulator of neuronal nuclear activities and/or gene expression, which may provide insight toward new molecular targets for modulating nociception at the level of primary afferent neurons.
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MESH Headings
- Animals
- Antibodies
- Blotting, Western
- Cell Membrane/metabolism
- Endoplasmic Reticulum/metabolism
- Ganglia, Spinal/metabolism
- Ganglia, Spinal/ultrastructure
- Immunohistochemistry
- Male
- Mice, 129 Strain
- Mice, Inbred C57BL
- Mice, Transgenic
- Microscopy, Confocal
- Microscopy, Immunoelectron
- Neurons/metabolism
- Neurons/ultrastructure
- Nuclear Envelope/metabolism
- Phosphopyruvate Hydratase/metabolism
- RNA, Messenger/metabolism
- Rats, Sprague-Dawley
- Real-Time Polymerase Chain Reaction
- Receptors, sigma/genetics
- Receptors, sigma/immunology
- Receptors, sigma/metabolism
- Sigma-1 Receptor
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Affiliation(s)
- Timur A Mavlyutov
- Department of Anesthesiology, University of Wisconsin, School of Medicine and Public Health, 1111 Highland Avenue, Madison, WI 53726, USA.
| | - Tyler Duellman
- Department of Anesthesiology, University of Wisconsin, School of Medicine and Public Health, 1111 Highland Avenue, Madison, WI 53726, USA
| | - Hung Tae Kim
- Department of Anesthesiology, University of Wisconsin, School of Medicine and Public Health, 1111 Highland Avenue, Madison, WI 53726, USA
| | - Miles L Epstein
- Department of Neuroscience, University of Wisconsin, School of Medicine and Public Health, 1300 University Avenue, Madison, WI 53706, USA
| | - Charlotte Leese
- Department of Biomedical Science, University of Sheffield, Firth Court, Sheffield S10 2TN, South Yorkshire, England, United Kingdom
| | - Bazbek A Davletov
- Department of Biomedical Science, University of Sheffield, Firth Court, Sheffield S10 2TN, South Yorkshire, England, United Kingdom
| | - Jay Yang
- Department of Anesthesiology, University of Wisconsin, School of Medicine and Public Health, 1111 Highland Avenue, Madison, WI 53726, USA.
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Halberstadt AL, Hyun J, Ruderman MA, Powell SB. Effects of the psychotomimetic benzomorphan N-allylnormetazocine (SKF 10,047) on prepulse inhibition of startle in mice. Pharmacol Biochem Behav 2016; 148:69-75. [PMID: 27236030 PMCID: PMC5662292 DOI: 10.1016/j.pbb.2016.05.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/16/2016] [Revised: 05/12/2016] [Accepted: 05/23/2016] [Indexed: 11/21/2022]
Abstract
N-allylnormetazocine (NANM; SKF 10,047) is a benzomorphan opioid that produces psychotomimetic effects. (+)-NANM is the prototypical agonist for the sigma-1 (σ1) receptor, and there is a widespread belief that the hallucinogenic effects of NANM and other benzomorphan derivatives are mediated by interactions with σ1 sites. However, NANM is also an agonist at the κ opioid receptor (KOR) and binds to the PCP site located within the channel pore of the NMDA receptor, interactions that could potentially contribute to the effects of NANM. NMDA receptor antagonists such as phencyclidine (PCP) and ketamine are known to disrupt prepulse inhibition (PPI) of acoustic startle, a measure of sensorimotor gating, in rodents. We recently found that racemic NANM disrupts PPI in rats, but it is not clear whether the effect is mediated by blockade of the NMDA receptor, or alternatively whether interactions with KOR and σ1 receptors are involved. The present studies examined whether NANM and its stereoisomers alter PPI in C57BL/6J mice, and tested whether the effects on PPI are mediated by KOR or σ1 receptors. Racemic NANM produced a dose-dependent disruption of PPI (3-30mg/kg SC). (+)-NANM also disrupted PPI, whereas (-)-NANM was ineffective. Pretreatment with the selective KOR antagonist nor-binaltorphimine (10mg/kg SC) or the selective σ1 antagonist NE-100 (1mg/kg IP) failed to attenuate the reduction in PPI produced by racemic NANM. We also found that the selective KOR agonist (-)-U-50,488H (10-40mg/kg SC) had no effect on PPI. These findings confirm that NANM reduces sensorimotor gating in rodents, and indicate that the effect is mediated by interactions with the PCP receptor and not by activation of KOR or σ1 receptors. This observation is consistent with evidence indicating that the σ1 receptor is not linked to hallucinogenic or psychotomimetic effects.
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Affiliation(s)
- Adam L Halberstadt
- Department of Psychiatry, University of California San Diego, La Jolla, CA, United States; Research Service, VA San Diego Healthcare System, San Diego, CA, United States.
| | - James Hyun
- Department of Psychiatry, University of California San Diego, La Jolla, CA, United States
| | - Michael A Ruderman
- Department of Psychiatry, University of California San Diego, La Jolla, CA, United States
| | - Susan B Powell
- Department of Psychiatry, University of California San Diego, La Jolla, CA, United States; Research Service, VA San Diego Healthcare System, San Diego, CA, United States
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Abstract
Two different strategies have been developed for imaging the proliferative status of solid tumors with the functional imaging technique, Positron Emission Tomography (PET). The first strategy uses carbon-11 labeled thymidine and/or, more recently, fluorine-18 labeled thymidine analogs. These agents are a substrate for the enzyme thymidine kinase-1 (TK-1) and provide a pulse label of the number of cells in S phase. The second method for imaging the proliferative status of a tumor uses radiolabeled ligands that bind to the sigma-2 receptor which has a 10-fold higher density in proliferating (P) tumor cells versus quiescent (Q) tumor cells. This article compares and contrasts the two different strategies for imaging the proliferative status of solid tumors, and describes the strengths and weaknesses of each approach.
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46
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Scouting new sigma receptor ligands: Synthesis, pharmacological evaluation and molecular modeling of 1,3-dioxolane-based structures and derivatives. Eur J Med Chem 2016; 112:1-19. [DOI: 10.1016/j.ejmech.2016.01.059] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Revised: 01/13/2016] [Accepted: 01/30/2016] [Indexed: 11/23/2022]
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Romero L, Merlos M, Vela JM. Antinociception by Sigma-1 Receptor Antagonists: Central and Peripheral Effects. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2016; 75:179-215. [PMID: 26920013 DOI: 10.1016/bs.apha.2015.11.003] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
There is plenty of evidence supporting the modulatory role of sigma-1 receptors (σ1Rs) in nociception, mainly based on the pain-attenuated phenotype of σ1R knockout mice and on the antinociceptive effect exerted by σ1R antagonists, particularly in nonacute sensitizing conditions involving sustained afferent drive, activity-dependent plasticity/sensitization, and ultimately pain hypersensitivity, as it is the case in chronic pains of different etiology. Antinociceptive effects of σ1R antagonists both when acting alone and in combination with opioids (to enhance opioid analgesia) have been reported at both central and peripheral sites. At the central level, findings at the behavioral (animal pain models), electrophysiological (spinal wind-up recordings), neurochemical (spinal release of neurotransmitters) and molecular (NMDAR function) level supports a role for σ1R antagonists in inhibiting augmented excitability secondary to sustained afferent input. Attenuation of activity-induced plastic changes (central sensitization) following tissue injury/inflammation or nerve damage could thus underlie the central inhibitory effect of σ1R antagonists. Moreover, recent pieces of information confirm the involvement of σ1R in mechanisms regulating pain at the periphery, where σ1Rs are highly expressed, particularly in dorsal root ganglia. Indeed, local peripheral administration of σ1R antagonists reduces inflammatory hyperalgesia. Potentiation of opioid analgesia is also supported, particularly at supraspinal sites and at the periphery, where locally administered σ1R antagonists unmask opioid analgesia. Altogether, whereas σ1R activation is coupled to pain facilitation and inhibition of opioid antinociception, σ1R antagonism inhibits pain hypersensitivity and "releases the brake" enabling opioids to exert enhanced antinociceptive effects, both at the central nervous system and at the periphery.
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Affiliation(s)
- Luz Romero
- Drug Discovery and Preclinical Development, ESTEVE, Parc Científic de Barcelona, Baldiri Reixac 4-8, Barcelona, Spain
| | - Manuel Merlos
- Drug Discovery and Preclinical Development, ESTEVE, Parc Científic de Barcelona, Baldiri Reixac 4-8, Barcelona, Spain
| | - José Miguel Vela
- Drug Discovery and Preclinical Development, ESTEVE, Parc Científic de Barcelona, Baldiri Reixac 4-8, Barcelona, Spain.
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Shanmugam AK, Mysona BA, Wang J, Zhao J, Tawfik A, Sanders A, Markand S, Zorrilla E, Ganapathy V, Bollinger KE, Smith SB. Progesterone Receptor Membrane Component 1 (PGRMC1) Expression in Murine Retina. Curr Eye Res 2015; 41:1105-1112. [PMID: 26642738 DOI: 10.3109/02713683.2015.1085579] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
PURPOSE Sigma receptors 1 (σR1) and 2 (σR2) are thought to be two distinct proteins which share the ability to bind multiple ligands, several of which are common to both receptors. Whether σR1 and σR2 share overlapping biological functions is unknown. Recently, progesterone receptor membrane component 1 (PGRMC1) was shown to contain the putative σR2 binding site. PGRMC1 has not been studied in retina. We hypothesize that biological interactions between σR1 and PGRMC1 will be evidenced by compensatory upregulation of PGRMC1 in σR1-/- mice. METHODS Immunofluorescence, RT-PCR, and immunoblotting methods were used to analyze expression of PGRMC1 in wild-type mouse retina. Tissues from σR1-/- mice were used to investigate whether a biological interaction exists between σR1 and PGRMC1. RESULTS In the eye, PGRMC1 is expressed in corneal epithelium, lens, ciliary body epithelium, and retina. In retina, PGRMC1 is present in Müller cells and retinal pigment epithelium. This expression pattern is similar, but not identical to σR1. PGRMC1 protein levels in neural retina and eye cup from σR1-/- mice did not differ from wild-type mice. Nonocular tissues, lung, heart, and kidney showed similar Pgrmc1 gene expression in wild-type and σR1-/- mice. In contrast, liver, brain, and intestine showed increased Pgrmc1 gene expression in σR1-/- mice. CONCLUSION Despite potential biological overlap, deletion of σR1 did not result in a compensatory change in PGRMC1 protein levels in σR1-/- mouse retina. Increased Pgrmc1 gene expression in organs with high lipid content such as liver, brain, and intestine indicates a possible tissue-specific interaction between σR1 and PGRMC1. The current studies establish the presence of PGRMC1 in retina and lay the foundation for analysis of its biological function.
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Affiliation(s)
- Arul K Shanmugam
- a Department of Cellular Biology and Anatomy , Medical College of Georgia, Georgia Regents University , Augusta , GA , USA.,b James & Jean Culver Vision Discovery Institute , Georgia Regents University , Augusta , GA , USA
| | - Barbara A Mysona
- a Department of Cellular Biology and Anatomy , Medical College of Georgia, Georgia Regents University , Augusta , GA , USA.,b James & Jean Culver Vision Discovery Institute , Georgia Regents University , Augusta , GA , USA
| | - Jing Wang
- a Department of Cellular Biology and Anatomy , Medical College of Georgia, Georgia Regents University , Augusta , GA , USA.,b James & Jean Culver Vision Discovery Institute , Georgia Regents University , Augusta , GA , USA
| | - Jing Zhao
- b James & Jean Culver Vision Discovery Institute , Georgia Regents University , Augusta , GA , USA.,c Department of Ophthalmology , Medical College of Georgia, Georgia Regents University , Augusta , GA , USA
| | - Amany Tawfik
- a Department of Cellular Biology and Anatomy , Medical College of Georgia, Georgia Regents University , Augusta , GA , USA.,b James & Jean Culver Vision Discovery Institute , Georgia Regents University , Augusta , GA , USA
| | - A Sanders
- a Department of Cellular Biology and Anatomy , Medical College of Georgia, Georgia Regents University , Augusta , GA , USA
| | - Shanu Markand
- a Department of Cellular Biology and Anatomy , Medical College of Georgia, Georgia Regents University , Augusta , GA , USA.,b James & Jean Culver Vision Discovery Institute , Georgia Regents University , Augusta , GA , USA
| | - Eric Zorrilla
- d Harold L. Dorris Neurological Research Institute , The Scripps Research Institute , La Jolla , CA , USA
| | - Vadivel Ganapathy
- b James & Jean Culver Vision Discovery Institute , Georgia Regents University , Augusta , GA , USA.,e Department of Cell Biology and Biochemistry , Texas Tech University Health Sciences Center , Lubbock , TX , USA
| | - Kathryn E Bollinger
- a Department of Cellular Biology and Anatomy , Medical College of Georgia, Georgia Regents University , Augusta , GA , USA.,b James & Jean Culver Vision Discovery Institute , Georgia Regents University , Augusta , GA , USA.,c Department of Ophthalmology , Medical College of Georgia, Georgia Regents University , Augusta , GA , USA
| | - Sylvia B Smith
- a Department of Cellular Biology and Anatomy , Medical College of Georgia, Georgia Regents University , Augusta , GA , USA.,b James & Jean Culver Vision Discovery Institute , Georgia Regents University , Augusta , GA , USA.,c Department of Ophthalmology , Medical College of Georgia, Georgia Regents University , Augusta , GA , USA
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Moriguchi S, Sakagami H, Yabuki Y, Sasaki Y, Izumi H, Zhang C, Han F, Fukunaga K. Stimulation of Sigma-1 Receptor Ameliorates Depressive-like Behaviors in CaMKIV Null Mice. Mol Neurobiol 2015; 52:1210-1222. [PMID: 25316382 DOI: 10.1007/s12035-014-8923-2] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2014] [Accepted: 10/06/2014] [Indexed: 01/22/2023]
Abstract
Sigma-1 receptor (Sig-1R) is a molecular chaperone regulating calcium efflux from the neuronal endoplasmic reticulum to the mitochondria. Calcium/calmodulin-dependent protein kinase IV (CaMKIV) null mice exhibit depressive-like behaviors and impaired neurogenesis as assessed by bromodeoxyuridine (BrdU) incorporation into newborn cells of the hippocampal dentate gyrus (DG). Here, we demonstrate that chronic stimulation of Sig-1R by treatment with the agonist SA4503 or the SSRI fluvoxamine for 14 days improves depressive-like behaviors in CaMKIV null mice. By contrast, treatment with paroxetine, which lacks affinity for Sig-1R, did not alter these behaviors. Reduced numbers of BrdU-positive cells and decreased brain-derived neurotrophic factor (BDNF) mRNA expression and protein kinase B (Akt; Ser-473) phosphorylation seen in the DG of CaMKIV null mice were significantly rescued by chronic Sig-1R stimulation. Interestingly, reduced ATP production observed in the DG of CaMKIV null mice was improved by chronic Sig-1R stimulation. Such stimulation also improved hippocampal long-term potentiation (LTP) induction and maintenance, which are impaired in the DG of CaMKIV null mice. LTP rescue was closely associated with both increases in calcium/calmodulin-dependent protein kinase II (CaMKII) autophosphorylation and GluA1 (Ser-831) phosphorylation. Taken together, Sig-1R stimulation by SA4503 or fluvoxamine treatment increased hippocampal neurogenesis, which is closely associated with amelioration of depressive-like behaviors in CaMKIV null mice.
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Affiliation(s)
- Shigeki Moriguchi
- Department of Pharmacology, Graduate School of Pharmaceutical Sciences, Tohoku University, 6-3 Aramaki-Aoba, Aoba-ku, Sendai, Miyagi, 980-8578, Japan.
| | - Hiroyuki Sakagami
- Department of Anatomy, Kitasato University School of Medicine, Sagamihara, Japan
| | - Yasushi Yabuki
- Department of Pharmacology, Graduate School of Pharmaceutical Sciences, Tohoku University, 6-3 Aramaki-Aoba, Aoba-ku, Sendai, Miyagi, 980-8578, Japan
| | - Yuzuru Sasaki
- Department of Pharmacology, Graduate School of Pharmaceutical Sciences, Tohoku University, 6-3 Aramaki-Aoba, Aoba-ku, Sendai, Miyagi, 980-8578, Japan
| | - Hisanao Izumi
- Department of Pharmacology, Graduate School of Pharmaceutical Sciences, Tohoku University, 6-3 Aramaki-Aoba, Aoba-ku, Sendai, Miyagi, 980-8578, Japan
| | - Chen Zhang
- Department of Pharmacy, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, China
| | - Feng Han
- Department of Pharmacy, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, China
| | - Kohji Fukunaga
- Department of Pharmacology, Graduate School of Pharmaceutical Sciences, Tohoku University, 6-3 Aramaki-Aoba, Aoba-ku, Sendai, Miyagi, 980-8578, Japan.
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50
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Wang J, Shanmugam A, Markand S, Zorrilla E, Ganapathy V, Smith SB. Sigma 1 receptor regulates the oxidative stress response in primary retinal Müller glial cells via NRF2 signaling and system xc(-), the Na(+)-independent glutamate-cystine exchanger. Free Radic Biol Med 2015; 86:25-36. [PMID: 25920363 PMCID: PMC4554890 DOI: 10.1016/j.freeradbiomed.2015.04.009] [Citation(s) in RCA: 95] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2014] [Revised: 04/02/2015] [Accepted: 04/07/2015] [Indexed: 01/18/2023]
Abstract
Oxidative stress figures prominently in retinal diseases, including diabetic retinopathy, and glaucoma. Ligands for σ1R, a unique transmembrane protein localized to the endoplasmic reticulum, mitochondria, and nuclear and plasma membranes, have profound retinal neuroprotective properties in vitro and in vivo. Studies to determine the mechanism of σ1R-mediated retinal neuroprotection have focused mainly on neurons. Little is known about the effects of σ1R on Müller cell function, yet these radial glial cells are essential for homeostatic support of the retina. Here we investigated whether σ1R mediates the oxidative stress response of Müller cells using wild-type (WT) and σ1R-knockout (σ1RKO) mice. We observed increased endogenous reactive oxygen species (ROS) levels in σ1RKO Müller cells compared to WT, which was accompanied by decreased expression of Sod1, catalase, Nqo1, Hmox1, Gstm6, and Gpx1. The protein levels of SOD1, CAT, NQO1, and GPX1 were also significantly decreased. The genes encoding these antioxidants contain an antioxidant response element (ARE), which under stress is activated by NRF2, a transcription factor that typically resides in the cytoplasm bound by KEAP1. In the σ1RKO Müller cells Nrf2 expression was decreased significantly at the gene (and protein) level, whereas Keap1 gene (and protein) levels were markedly increased. NRF2-ARE binding affinity was decreased markedly in σ1RKO Müller cells. We investigated system xc(-), the cystine-glutamate exchanger important for synthesis of glutathione (GSH), and observed decreased function in σ1RKO Müller cells compared to WT as well as decreased GSH and GSH/GSSG ratios. This was accompanied by decreased gene and protein levels of xCT, the unique component of system xc(-). We conclude that Müller glial cells lacking σ1R manifest elevated ROS, perturbation of antioxidant balance, suppression of NRF2 signaling, and impaired function of system xc(-). The data suggest that the oxidative stress-mediating function of retinal Müller glial cells may be compromised in the absence of σ1R. The neuroprotective role of σ1R may be linked directly to the oxidative stress-mediating properties of supportive glial cells.
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Affiliation(s)
- Jing Wang
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta, GA 30912-2000, USA; James and Jean Culver Vision Discovery Institute, Augusta, GA 30912-2000, USA
| | - Arul Shanmugam
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta, GA 30912-2000, USA; James and Jean Culver Vision Discovery Institute, Augusta, GA 30912-2000, USA
| | - Shanu Markand
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta, GA 30912-2000, USA; James and Jean Culver Vision Discovery Institute, Augusta, GA 30912-2000, USA
| | - Eric Zorrilla
- Harold L. Dorris Neurological Research Institute, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Vadivel Ganapathy
- James and Jean Culver Vision Discovery Institute, Augusta, GA 30912-2000, USA; Department of Biochemistry and Molecular Biology, Medical College of Georgia, Augusta, GA 30912-2000, USA
| | - Sylvia B Smith
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta, GA 30912-2000, USA; James and Jean Culver Vision Discovery Institute, Augusta, GA 30912-2000, USA; Department of Ophthalmology, Medical College of Georgia, Georgia Regents University, Augusta, GA 30912-2000, USA.
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