1
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Hu J, Park SJ, Walter T, Orozco IJ, O'Dea G, Ye X, Du J, Lü W. Physiological temperature drives TRPM4 ligand recognition and gating. Nature 2024; 630:509-515. [PMID: 38750366 PMCID: PMC11168932 DOI: 10.1038/s41586-024-07436-7] [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: 02/15/2024] [Accepted: 04/17/2024] [Indexed: 06/14/2024]
Abstract
Temperature profoundly affects macromolecular function, particularly in proteins with temperature sensitivity1,2. However, its impact is often overlooked in biophysical studies that are typically performed at non-physiological temperatures, potentially leading to inaccurate mechanistic and pharmacological insights. Here we demonstrate temperature-dependent changes in the structure and function of TRPM4, a temperature-sensitive Ca2+-activated ion channel3-7. By studying TRPM4 prepared at physiological temperature using single-particle cryo-electron microscopy, we identified a 'warm' conformation that is distinct from those observed at lower temperatures. This conformation is driven by a temperature-dependent Ca2+-binding site in the intracellular domain, and is essential for TRPM4 function in physiological contexts. We demonstrated that ligands, exemplified by decavanadate (a positive modulator)8 and ATP (an inhibitor)9, bind to different locations of TRPM4 at physiological temperatures than at lower temperatures10,11, and that these sites have bona fide functional relevance. We elucidated the TRPM4 gating mechanism by capturing structural snapshots of its different functional states at physiological temperatures, revealing the channel opening that is not observed at lower temperatures. Our study provides an example of temperature-dependent ligand recognition and modulation of an ion channel, underscoring the importance of studying macromolecules at physiological temperatures. It also provides a potential molecular framework for deciphering how thermosensitive TRPM channels perceive temperature changes.
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Affiliation(s)
- Jinhong Hu
- Van Andel Institute, Grand Rapids, MI, USA
| | | | - Tyler Walter
- Van Andel Institute, Grand Rapids, MI, USA
- Zoetis, Kalamazoo, MI, USA
| | - Ian J Orozco
- Van Andel Institute, Grand Rapids, MI, USA
- AnaBios, San Diego, CA, USA
| | | | - Xinyu Ye
- Van Andel Institute, Grand Rapids, MI, USA
| | - Juan Du
- Van Andel Institute, Grand Rapids, MI, USA.
| | - Wei Lü
- Van Andel Institute, Grand Rapids, MI, USA.
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2
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Huffer K, Oskoui EV, Swartz KJ. Conservation of the cooling agent binding pocket within the TRPM subfamily. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.20.595003. [PMID: 38826484 PMCID: PMC11142142 DOI: 10.1101/2024.05.20.595003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2024]
Abstract
Transient Receptor Potential (TRP) channels are a large and diverse family of tetrameric cation selective channels that are activated by many different types of stimuli, including noxious heat or cold, organic ligands such as vanilloids or cooling agents, or intracellular Ca2+. Structures available for all subtypes of TRP channels reveal that the transmembrane domains are closely related despite their unique sensitivity to activating stimuli. Here we use computational and electrophysiological approaches to explore the conservation of the cooling agent binding pocket identified within the S1-S4 domain of the Melastatin subfamily member TRPM8, the mammalian sensor of noxious cold, with other TRPM channel subtypes. We find that a subset of TRPM channels, including TRPM2, TRPM4 and TRPM5, contain well-conserved cooling agent binding pockets. We then show how the cooling agent icilin modulates activation of TRPM4 to intracellular Ca2+, enhancing the sensitivity of the channel to Ca2+ and diminishing outward-rectification to promote opening at negative voltages. Mutations known to promote or diminish activation of TRPM8 by icilin similarly alter activation of TRPM4 by the cooling agent, suggesting that icilin binds to the cooling agent binding pocket to promote opening of the channel. These findings demonstrate that TRPM4 and TRPM8 channels share related cooling agent binding pockets that are allosterically coupled to opening of the pore.
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Affiliation(s)
- Kate Huffer
- Molecular Physiology and Biophysics Section, Porter Neuroscience Research Center, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892
| | | | - Kenton J. Swartz
- Molecular Physiology and Biophysics Section, Porter Neuroscience Research Center, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892
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3
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Bonsignore G, Martinotti S, Ranzato E. Wound Repair and Ca 2+ Signalling Interplay: The Role of Ca 2+ Channels in Skin. Cells 2024; 13:491. [PMID: 38534335 DOI: 10.3390/cells13060491] [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: 01/24/2024] [Revised: 03/02/2024] [Accepted: 03/08/2024] [Indexed: 03/28/2024] Open
Abstract
The process of wound healing is intricate and tightly controlled, involving a number of different cellular and molecular processes. Numerous cellular functions, especially those related to wound healing, depend critically on calcium ions (Ca2+). Ca2+ channels are proteins involved in signal transduction and communication inside cells that allow calcium ions to pass through cell membranes. Key Ca2+ channel types involved in wound repair are described in this review.
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Affiliation(s)
- Gregorio Bonsignore
- Dipartimento di Scienze e Innovazione Tecnologica (DiSIT), University of Piemonte Orientale, 15121 Alessandria, Italy
| | - Simona Martinotti
- Dipartimento di Scienze e Innovazione Tecnologica (DiSIT), University of Piemonte Orientale, 15121 Alessandria, Italy
- SSD Laboratori di Ricerca-DAIRI, Azienda Ospedaliero-Universitaria SS. Antonio e Biagio e Cesare Arrigo, 15121 Alessandria, Italy
| | - Elia Ranzato
- Dipartimento di Scienze e Innovazione Tecnologica (DiSIT), University of Piemonte Orientale, 15121 Alessandria, Italy
- SSD Laboratori di Ricerca-DAIRI, Azienda Ospedaliero-Universitaria SS. Antonio e Biagio e Cesare Arrigo, 15121 Alessandria, Italy
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4
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Richter P, Andersen G, Kahlenberg K, Mueller AU, Pirkwieser P, Boger V, Somoza V. Sodium-Permeable Ion Channels TRPM4 and TRPM5 are Functional in Human Gastric Parietal Cells in Culture and Modulate the Cellular Response to Bitter-Tasting Food Constituents. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2024; 72:4906-4917. [PMID: 38378185 PMCID: PMC10921469 DOI: 10.1021/acs.jafc.3c09085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2023] [Revised: 01/28/2024] [Accepted: 01/29/2024] [Indexed: 02/22/2024]
Abstract
Gastric parietal cells secrete chloride ions and protons to form hydrochloric acid. Besides endogenous stimulants, e.g., acetylcholine, bitter-tasting food constituents, e.g., caffeine, induce proton secretion via interaction with bitter taste receptors (TAS2Rs), leading to increased cytosolic Ca2+ and cAMP concentrations. We hypothesized TAS2R activation by bitter tastants to result in proton secretion via cellular Na+ influx mediated by transient receptor potential channels (TRP) M4 and M5 in immortalized human parietal HGT-1 cells. Using the food-derived TAS2R agonists caffeine and l-arginine, we demonstrate both bitter compounds to induce a TRPM4/M5-mediated Na+ influx, with EC50 values of 0.65 and 10.38 mM, respectively, that stimulates cellular proton secretion. Functional involvement of TAS2Rs in the caffeine-evoked effect was demonstrated by means of the TAS2R antagonist homoeriodictyol, and stably CRISPR-Cas9-edited TAS2R43ko cells. Building on previous results, these data further support the suitability of HGT-1 cells as a surrogate cell model for taste cells. In addition, TRPM4/M5 mediated a Na+ influx after stimulating HGT-1 cells with the acetylcholine analogue carbachol, indicating an interaction of the digestion-associated cholinergic pathway with a taste-signaling pathway in parietal cells.
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Affiliation(s)
- Phil Richter
- TUM
School of Life Sciences Weihenstephan, Technical
University of Munich, Alte Akademie 8, Freising 85354, Germany
- Leibniz
Institute for Food Systems Biology at the Technical University of
Munich, Lise-Meitner-Str.
34, Freising 85354, Germany
| | - Gaby Andersen
- Leibniz
Institute for Food Systems Biology at the Technical University of
Munich, Lise-Meitner-Str.
34, Freising 85354, Germany
| | - Kristin Kahlenberg
- Leibniz
Institute for Food Systems Biology at the Technical University of
Munich, Lise-Meitner-Str.
34, Freising 85354, Germany
| | - Alina Ulrike Mueller
- Leibniz
Institute for Food Systems Biology at the Technical University of
Munich, Lise-Meitner-Str.
34, Freising 85354, Germany
| | - Philip Pirkwieser
- Leibniz
Institute for Food Systems Biology at the Technical University of
Munich, Lise-Meitner-Str.
34, Freising 85354, Germany
| | - Valerie Boger
- Leibniz
Institute for Food Systems Biology at the Technical University of
Munich, Lise-Meitner-Str.
34, Freising 85354, Germany
| | - Veronika Somoza
- Leibniz
Institute for Food Systems Biology at the Technical University of
Munich, Lise-Meitner-Str.
34, Freising 85354, Germany
- Chair
of Nutritional Systems Biology, TUM School of Life Sciences, Technical University of Munich, Lise-Meitner-Str. 34, Freising 85354, Germany
- Department
of Physiological Chemistry, Faculty of Chemistry, University of Vienna, Josef-Holaubek-Platz 2 (UZA II), Vienna 1090, Austria
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5
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Chubanov V, Köttgen M, Touyz RM, Gudermann T. TRPM channels in health and disease. Nat Rev Nephrol 2024; 20:175-187. [PMID: 37853091 DOI: 10.1038/s41581-023-00777-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/25/2023] [Indexed: 10/20/2023]
Abstract
Different cell channels and transporters tightly regulate cytoplasmic levels and the intraorganelle distribution of cations. Perturbations in these processes lead to human diseases that are frequently associated with kidney impairment. The family of melastatin-related transient receptor potential (TRPM) channels, which has eight members in mammals (TRPM1-TRPM8), includes ion channels that are highly permeable to divalent cations, such as Ca2+, Mg2+ and Zn2+ (TRPM1, TRPM3, TRPM6 and TRPM7), non-selective cation channels (TRPM2 and TRPM8) and monovalent cation-selective channels (TRPM4 and TRPM5). Three family members contain an enzymatic protein moiety: TRPM6 and TRPM7 are fused to α-kinase domains, whereas TRPM2 is linked to an ADP-ribose-binding NUDT9 homology domain. TRPM channels also function as crucial cellular sensors involved in many physiological processes, including mineral homeostasis, blood pressure, cardiac rhythm and immunity, as well as photoreception, taste reception and thermoreception. TRPM channels are abundantly expressed in the kidney. Mutations in TRPM genes cause several inherited human diseases, and preclinical studies in animal models of human disease have highlighted TRPM channels as promising new therapeutic targets. Here, we provide an overview of this rapidly evolving research area and delineate the emerging role of TRPM channels in kidney pathophysiology.
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Affiliation(s)
- Vladimir Chubanov
- Walther-Straub Institute of Pharmacology and Toxicology, LMU Munich, Munich, Germany.
| | - Michael Köttgen
- Renal Division, Department of Medicine, Medical Center, Faculty of Medicine, University of Freiburg, Freiburg, Germany
- CIBSS - Centre for Integrative Biological Signalling Studies, Freiburg, Germany
| | - Rhian M Touyz
- Research Institute of McGill University Health Centre, McGill University, Montreal, Quebec, Canada
| | - Thomas Gudermann
- Walther-Straub Institute of Pharmacology and Toxicology, LMU Munich, Munich, Germany.
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6
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Niu L, Liu H, Li X, Wang L, Hua H, Cao Q, Xiang Q, Cai T, Zhu D. Design, synthesis, and biological evaluation of 2-(naphthalen-1-yloxy)-N-phenylacetamide derivatives as TRPM4 inhibitors for the treatment of prostate cancer. Bioorg Med Chem 2024; 98:117584. [PMID: 38168629 DOI: 10.1016/j.bmc.2023.117584] [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: 11/03/2023] [Revised: 12/11/2023] [Accepted: 12/26/2023] [Indexed: 01/05/2024]
Abstract
Transient receptor potential melastatin 4 (TRPM4) is considered to be a potential target for cancer and other human diseases. Herein, a series of 2-(naphthalen-1-yloxy)-N-phenylacetamide derivatives were designed and synthesized as new TRPM4 inhibitors, aiming to improve cellular potency. One of the most promising compounds, 7d (ZX08903), displayed promising antiproliferative activity against prostate cancer cell lines. 7d also suppressed colony formation and the expression of androgen receptor (AR) protein in prostate cancer cells. Furthermore, 7d can concentration-dependently induce cell apoptosis in prostate cancer cells. Collectively, these findings indicated that compound 7d may serve as a promising lead compound for further anticancer drug development.
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Affiliation(s)
- Le Niu
- Guoke Ningbo Life Science and Health Industry Research Institute, Ningbo No.2 Hospital, Ningbo, 315010, China; Department of Urology, the Second Affiliated Hospital of Nanjing Medical University, and Department of Medicinal Chemistry, School of Pharmacy, Nanjing Medical University, Nanjing, 211166, China
| | - Huina Liu
- Guoke Ningbo Life Science and Health Industry Research Institute, Ningbo No.2 Hospital, Ningbo, 315010, China
| | - Xiaomei Li
- Guoke Ningbo Life Science and Health Industry Research Institute, Ningbo No.2 Hospital, Ningbo, 315010, China
| | - Lin Wang
- Department of Urology, the Second Affiliated Hospital of Nanjing Medical University, and Department of Medicinal Chemistry, School of Pharmacy, Nanjing Medical University, Nanjing, 211166, China
| | - Hui Hua
- Guoke Ningbo Life Science and Health Industry Research Institute, Ningbo No.2 Hospital, Ningbo, 315010, China
| | - Qiaofeng Cao
- Department of Urology, the Second Affiliated Hospital of Nanjing Medical University, and Department of Medicinal Chemistry, School of Pharmacy, Nanjing Medical University, Nanjing, 211166, China
| | - Qiuping Xiang
- Guoke Ningbo Life Science and Health Industry Research Institute, Ningbo No.2 Hospital, Ningbo, 315010, China
| | - Ting Cai
- Guoke Ningbo Life Science and Health Industry Research Institute, Ningbo No.2 Hospital, Ningbo, 315010, China.
| | - Dongsheng Zhu
- Department of Urology, the Second Affiliated Hospital of Nanjing Medical University, and Department of Medicinal Chemistry, School of Pharmacy, Nanjing Medical University, Nanjing, 211166, China.
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7
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Davis MJ, Earley S, Li YS, Chien S. Vascular mechanotransduction. Physiol Rev 2023; 103:1247-1421. [PMID: 36603156 PMCID: PMC9942936 DOI: 10.1152/physrev.00053.2021] [Citation(s) in RCA: 45] [Impact Index Per Article: 45.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 09/26/2022] [Accepted: 10/04/2022] [Indexed: 01/07/2023] Open
Abstract
This review aims to survey the current state of mechanotransduction in vascular smooth muscle cells (VSMCs) and endothelial cells (ECs), including their sensing of mechanical stimuli and transduction of mechanical signals that result in the acute functional modulation and longer-term transcriptomic and epigenetic regulation of blood vessels. The mechanosensors discussed include ion channels, plasma membrane-associated structures and receptors, and junction proteins. The mechanosignaling pathways presented include the cytoskeleton, integrins, extracellular matrix, and intracellular signaling molecules. These are followed by discussions on mechanical regulation of transcriptome and epigenetics, relevance of mechanotransduction to health and disease, and interactions between VSMCs and ECs. Throughout this review, we offer suggestions for specific topics that require further understanding. In the closing section on conclusions and perspectives, we summarize what is known and point out the need to treat the vasculature as a system, including not only VSMCs and ECs but also the extracellular matrix and other types of cells such as resident macrophages and pericytes, so that we can fully understand the physiology and pathophysiology of the blood vessel as a whole, thus enhancing the comprehension, diagnosis, treatment, and prevention of vascular diseases.
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Affiliation(s)
- Michael J Davis
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, Missouri
| | - Scott Earley
- Department of Pharmacology, University of Nevada, Reno, Nevada
| | - Yi-Shuan Li
- Department of Bioengineering, University of California, San Diego, California
- Institute of Engineering in Medicine, University of California, San Diego, California
| | - Shu Chien
- Department of Bioengineering, University of California, San Diego, California
- Institute of Engineering in Medicine, University of California, San Diego, California
- Department of Medicine, University of California, San Diego, California
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8
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Ciaglia T, Vestuto V, Bertamino A, González-Muñiz R, Gómez-Monterrey I. On the modulation of TRPM channels: Current perspectives and anticancer therapeutic implications. Front Oncol 2023; 12:1065935. [PMID: 36844925 PMCID: PMC9948629 DOI: 10.3389/fonc.2022.1065935] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Accepted: 12/15/2022] [Indexed: 02/11/2023] Open
Abstract
The transient melastatin receptor potential (TRPM) ion channel subfamily functions as cellular sensors and transducers of critical biological signal pathways by regulating ion homeostasis. Some members of TRPM have been cloned from cancerous tissues, and their abnormal expressions in various solid malignancies have been correlated with cancer cell growth, survival, or death. Recent evidence also highlights the mechanisms underlying the role of TRPMs in tumor epithelial-mesenchymal transition (EMT), autophagy, and cancer metabolic reprogramming. These implications support TRPM channels as potential molecular targets and their modulation as an innovative therapeutic approach against cancer. Here, we discuss the general characteristics of the different TRPMs, focusing on current knowledge about the connection between TRPM channels and critical features of cancer. We also cover TRPM modulators used as pharmaceutical tools in biological trials and an indication of the only clinical trial with a TRPM modulator about cancer. To conclude, the authors describe the prospects for TRPM channels in oncology.
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Affiliation(s)
- Tania Ciaglia
- Dipartimento di Farmacia (DIFARMA), Università degli Studi di Salerno, Fisciano, Italy
| | - Vincenzo Vestuto
- Dipartimento di Farmacia (DIFARMA), Università degli Studi di Salerno, Fisciano, Italy
| | - Alessia Bertamino
- Dipartimento di Farmacia (DIFARMA), Università degli Studi di Salerno, Fisciano, Italy
| | - Rosario González-Muñiz
- Departamento de Biomiméticos, Instituto de Química Médica, Madrid, Spain,*Correspondence: Isabel Gómez-Monterrey, ; Rosario González-Muñiz,
| | - Isabel Gómez-Monterrey
- Dipartimento di Farmacia, Università degli Studi di Napoli “Federico II”, Naples, Italy,*Correspondence: Isabel Gómez-Monterrey, ; Rosario González-Muñiz,
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9
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Chen J, Chang Y, Zhu J, Peng Y, Li Z, Zhang K, Zhang Y, Lin C, Lin Z, Pan S, Huang K. Flufenamic acid improves survival and neurologic outcome after successful cardiopulmonary resuscitation in mice. J Neuroinflammation 2022; 19:214. [PMID: 36050694 PMCID: PMC9438280 DOI: 10.1186/s12974-022-02571-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Accepted: 08/19/2022] [Indexed: 11/10/2022] Open
Abstract
Background Brain injury is the main cause of high mortality and disability after successful cardiopulmonary resuscitation (CPR) from sudden cardiac arrest (CA). The transient receptor potential M4 (TRPM4) channel is a novel target for ameliorating blood–brain barrier (BBB) disruption and neuroinflammation. Herein, we tested whether flufenamic acid (FFA), which is reported to block TRPM4 with high potency, could confer neuroprotection against brain injury secondary to CA/CPR and whether its action was exerted by blocking the TRPM4 channel. Methods Wild-type (WT) and Trpm4 knockout (Trpm4−/−) mice subjected to 10-min CA/CPR were randomized to receive FFA or vehicle once daily. Post-CA/CPR brain injuries including neurologic deficits, survival rate, histological damage, edema formation, BBB destabilization and neuroinflammation were assessed. Results In WT mice subjected to CA/CPR, FFA was effective in improving survival and neurologic outcome, reducing neuropathological injuries, attenuating brain edema, lessening the leakage of IgG and Evans blue dye, restoring tight junction protein expression and promoting microglia/macrophages from the pro-inflammatory subtype toward the anti-inflammatory subtype. In comparison to WT mice, Trpm4−/− mice exhibited less neurologic deficiency, milder histological impairment, more BBB integrity and more anti-inflammatory microglia/macrophage polarization. As expected, FFA did not provide a benefit of superposition compared with vehicle in the Trpm4−/− mice after CA/CPR. Conclusions FFA mitigates BBB breach and modifies the functional status of microglia/macrophages, thereby improving survival and neurologic deficits following CA/CPR. The neuroprotective effects occur at least partially by interfering with the TRPM4 channel in the neurovascular unit. These results indicate the significant clinical potential of FFA to improve the prognosis for CA victims who are successfully resuscitated. Supplementary Information The online version contains supplementary material available at 10.1186/s12974-022-02571-2.
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Affiliation(s)
- Jiancong Chen
- Department of Neurology, Nanfang Hospital, Southern Medical University, Guangzhou North Avenue, Guangzhou, 1838#510515, China
| | - Yuan Chang
- Department of Neurology, Nanfang Hospital, Southern Medical University, Guangzhou North Avenue, Guangzhou, 1838#510515, China
| | - Juan Zhu
- Department of Neurology, Nanfang Hospital, Southern Medical University, Guangzhou North Avenue, Guangzhou, 1838#510515, China
| | - Yuqin Peng
- Department of Neurology, Nanfang Hospital, Southern Medical University, Guangzhou North Avenue, Guangzhou, 1838#510515, China
| | - Zheqi Li
- Department of Neurology, Nanfang Hospital, Southern Medical University, Guangzhou North Avenue, Guangzhou, 1838#510515, China
| | - Kunxue Zhang
- Department of Neurology, Nanfang Hospital, Southern Medical University, Guangzhou North Avenue, Guangzhou, 1838#510515, China
| | - Yuzhen Zhang
- Department of Neurology, Nanfang Hospital, Southern Medical University, Guangzhou North Avenue, Guangzhou, 1838#510515, China
| | - Chuman Lin
- Department of Neurology, Nanfang Hospital, Southern Medical University, Guangzhou North Avenue, Guangzhou, 1838#510515, China
| | - Zhenzhou Lin
- Department of Neurology, Nanfang Hospital, Southern Medical University, Guangzhou North Avenue, Guangzhou, 1838#510515, China
| | - Suyue Pan
- Department of Neurology, Nanfang Hospital, Southern Medical University, Guangzhou North Avenue, Guangzhou, 1838#510515, China.
| | - Kaibin Huang
- Department of Neurology, Nanfang Hospital, Southern Medical University, Guangzhou North Avenue, Guangzhou, 1838#510515, China.
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10
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Role of TRPM2 in brain tumours and potential as a drug target. Acta Pharmacol Sin 2022; 43:759-770. [PMID: 34108651 DOI: 10.1038/s41401-021-00679-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Accepted: 04/07/2021] [Indexed: 02/06/2023] Open
Abstract
Ion channels are ubiquitously expressed in almost all living cells, and are the third-largest category of drug targets, following enzymes and receptors. The transient receptor potential melastatin (TRPM) subfamily of ion channels are important to cell function and survival. Studies have shown upregulation of the TRPM family of ion channels in various brain tumours. Gliomas are the most prevalent form of primary malignant brain tumours with no effective treatment; thus, drug development is eagerly needed. TRPM2 is an essential ion channel for cell function and has important roles in oxidative stress and inflammation. In response to oxidative stress, ADP-ribose (ADPR) is produced, and in turn activates TRPM2 by binding to the NUDT9-H domain on the C-terminal. TRPM2 has been implicated in various cancers and is significantly upregulated in brain tumours. This article reviews the current understanding of TRPM2 in the context of brain tumours and overviews the effects of potential drug therapies targeting TRPM2 including hydrogen peroxide (H2O2), curcumin, docetaxel and selenium, paclitaxel and resveratrol, and botulinum toxin. It is long withstanding knowledge that gliomas are difficult to treat effectively, therefore investigating TRPM2 as a potential therapeutic target for brain tumours may be of considerable interest in the fields of ion channels and pharmacology.
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11
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Souza Bomfim GH, Niemeyer BA, Lacruz RS, Lis A. On the Connections between TRPM Channels and SOCE. Cells 2022; 11:1190. [PMID: 35406753 PMCID: PMC8997886 DOI: 10.3390/cells11071190] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 03/23/2022] [Accepted: 03/30/2022] [Indexed: 12/02/2022] Open
Abstract
Plasma membrane protein channels provide a passageway for ions to access the intracellular milieu. Rapid entry of calcium ions into cells is controlled mostly by ion channels, while Ca2+-ATPases and Ca2+ exchangers ensure that cytosolic Ca2+ levels ([Ca2+]cyt) are maintained at low (~100 nM) concentrations. Some channels, such as the Ca2+-release-activated Ca2+ (CRAC) channels and voltage-dependent Ca2+ channels (CACNAs), are highly Ca2+-selective, while others, including the Transient Receptor Potential Melastatin (TRPM) family, have broader selectivity and are mostly permeable to monovalent and divalent cations. Activation of CRAC channels involves the coupling between ORAI1-3 channels with the endoplasmic reticulum (ER) located Ca2+ store sensor, Stromal Interaction Molecules 1-2 (STIM1/2), a pathway also termed store-operated Ca2+ entry (SOCE). The TRPM family is formed by 8 members (TRPM1-8) permeable to Mg2+, Ca2+, Zn2+ and Na+ cations, and is activated by multiple stimuli. Recent studies indicated that SOCE and TRPM structure-function are interlinked in some instances, although the molecular details of this interaction are only emerging. Here we review the role of TRPM and SOCE in Ca2+ handling and highlight the available evidence for this interaction.
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Affiliation(s)
- Guilherme H. Souza Bomfim
- Department of Molecular Pathobiology, New York University College of Dentistry, New York, NY 10010, USA;
| | - Barbara A. Niemeyer
- Department of Molecular Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, 66421 Homburg, Germany;
| | - Rodrigo S. Lacruz
- Department of Molecular Pathobiology, New York University College of Dentistry, New York, NY 10010, USA;
| | - Annette Lis
- Department of Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, 66421 Homburg, Germany
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12
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Kovács ZM, Dienes C, Hézső T, Almássy J, Magyar J, Bányász T, Nánási PP, Horváth B, Szentandrássy N. Pharmacological Modulation and (Patho)Physiological Roles of TRPM4 Channel—Part 1: Modulation of TRPM4. Pharmaceuticals (Basel) 2022; 15:ph15010081. [PMID: 35056138 PMCID: PMC8781449 DOI: 10.3390/ph15010081] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Accepted: 01/06/2022] [Indexed: 02/06/2023] Open
Abstract
Transient receptor potential melastatin 4 is a unique member of the TRPM protein family and, similarly to TRPM5, is Ca2+-sensitive and permeable to monovalent but not divalent cations. It is widely expressed in many organs and is involved in several functions by regulating the membrane potential and Ca2+ homeostasis in both excitable and non-excitable cells. This part of the review discusses the pharmacological modulation of TRPM4 by listing, comparing, and describing both endogenous and exogenous activators and inhibitors of the ion channel. Moreover, other strategies used to study TRPM4 functions are listed and described. These strategies include siRNA-mediated silencing of TRPM4, dominant-negative TRPM4 variants, and anti-TRPM4 antibodies. TRPM4 is receiving more and more attention and is likely to be the topic of research in the future.
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Affiliation(s)
- Zsigmond Máté Kovács
- Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary; (Z.M.K.); (C.D.); (T.H.); (J.A.); (J.M.); (T.B.); (P.P.N.); (B.H.)
- Doctoral School of Molecular Medicine, University of Debrecen, 4032 Debrecen, Hungary
| | - Csaba Dienes
- Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary; (Z.M.K.); (C.D.); (T.H.); (J.A.); (J.M.); (T.B.); (P.P.N.); (B.H.)
- Doctoral School of Molecular Medicine, University of Debrecen, 4032 Debrecen, Hungary
| | - Tamás Hézső
- Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary; (Z.M.K.); (C.D.); (T.H.); (J.A.); (J.M.); (T.B.); (P.P.N.); (B.H.)
- Doctoral School of Molecular Medicine, University of Debrecen, 4032 Debrecen, Hungary
| | - János Almássy
- Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary; (Z.M.K.); (C.D.); (T.H.); (J.A.); (J.M.); (T.B.); (P.P.N.); (B.H.)
| | - János Magyar
- Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary; (Z.M.K.); (C.D.); (T.H.); (J.A.); (J.M.); (T.B.); (P.P.N.); (B.H.)
- Division of Sport Physiology, Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary
| | - Tamás Bányász
- Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary; (Z.M.K.); (C.D.); (T.H.); (J.A.); (J.M.); (T.B.); (P.P.N.); (B.H.)
| | - Péter P. Nánási
- Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary; (Z.M.K.); (C.D.); (T.H.); (J.A.); (J.M.); (T.B.); (P.P.N.); (B.H.)
- Department of Dental Physiology and Pharmacology, Faculty of Dentistry, University of Debrecen, 4032 Debrecen, Hungary
| | - Balázs Horváth
- Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary; (Z.M.K.); (C.D.); (T.H.); (J.A.); (J.M.); (T.B.); (P.P.N.); (B.H.)
- Faculty of Pharmacy, University of Debrecen, 4032 Debrecen, Hungary
| | - Norbert Szentandrássy
- Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary; (Z.M.K.); (C.D.); (T.H.); (J.A.); (J.M.); (T.B.); (P.P.N.); (B.H.)
- Department of Basic Medical Sciences, Faculty of Dentistry, University of Debrecen, 4032 Debrecen, Hungary
- Correspondence:
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13
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Zhou Z, Xi R, Liu J, Peng X, Zhao L, Zhou X, Li J, Zheng X, Xu X. TAS2R16 Activation Suppresses LPS-Induced Cytokine Expression in Human Gingival Fibroblasts. Front Immunol 2022; 12:726546. [PMID: 34975834 PMCID: PMC8714777 DOI: 10.3389/fimmu.2021.726546] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Accepted: 11/30/2021] [Indexed: 02/05/2023] Open
Abstract
Sustained and non-resolved inflammation is a characteristic of periodontitis. Upon acute inflammation, gingival fibroblasts release cytokines to recruit immune cells to counter environmental stimuli. The intricate regulation of pro-inflammatory signaling pathways, such as NF-κB, is necessary to maintain periodontal homeostasis. Nonetheless, how inflammation is resolved has not yet been elucidated. In this study, 22 subtypes of taste receptor family 2 (TAS2Rs), as well as the downstream machineries of Gα-gustducin and phospholipase C-β2 (PLCβ2), were identified in human gingival fibroblasts (HGFs). Various bitter agonists could induce an intensive cytosolic Ca2+ response in HGFs. More importantly, TAS2R16 was expressed at a relatively high level, and its agonist, salicin, showed robust Ca2+ evocative effects in HGFs. Activation of TAS2R16 signaling by salicin inhibited the release of lipopolysaccharide (LPS)-induced pro-inflammatory cytokines, at least in part, by repressing LPS-induced intracellular cAMP elevation and NF-κB p65 nuclear translocation in HGFs. These findings indicate that TAS2Rs activation in HGFs may mediate endogenous pro-inflammation resolution by antagonizing NF-κB signaling, providing a novel paradigm and treatment target for the better management of periodontitis.
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Affiliation(s)
- Zhiyan Zhou
- State Key Laboratory of Oral Diseases and National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China.,Department of Cariology and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Ranhui Xi
- State Key Laboratory of Oral Diseases and National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China.,Department of Cariology and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Jiaxin Liu
- State Key Laboratory of Oral Diseases and National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China.,Department of Cariology and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Xian Peng
- State Key Laboratory of Oral Diseases and National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Lei Zhao
- State Key Laboratory of Oral Diseases and National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China.,Department of Periodontology, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Xuedong Zhou
- State Key Laboratory of Oral Diseases and National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China.,Department of Cariology and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Jiyao Li
- State Key Laboratory of Oral Diseases and National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China.,Department of Cariology and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Xin Zheng
- State Key Laboratory of Oral Diseases and National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China.,Department of Cariology and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Xin Xu
- State Key Laboratory of Oral Diseases and National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China.,Department of Cariology and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
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14
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Smith JC. Respiratory rhythm and pattern generation: Brainstem cellular and circuit mechanisms. HANDBOOK OF CLINICAL NEUROLOGY 2022; 188:1-35. [PMID: 35965022 DOI: 10.1016/b978-0-323-91534-2.00004-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Breathing movements in mammals are driven by rhythmic neural activity automatically generated within spatially and functionally organized brainstem neural circuits comprising the respiratory central pattern generator (CPG). This chapter reviews up-to-date experimental information and theoretical studies of the cellular and circuit mechanisms of respiratory rhythm and pattern generation operating within critical components of this CPG in the lower brainstem. Over the past several decades, there have been substantial advances in delineating the spatial architecture of essential medullary regions and their regional cellular and circuit properties required to understand rhythm and pattern generation mechanisms. A fundamental concept is that the circuits in these regions have rhythm-generating capabilities at multiple cellular and circuit organization levels. The regional cellular properties, circuit organization, and control mechanisms allow flexible expression of neural activity patterns for a repertoire of respiratory behaviors under various physiologic conditions that are dictated by requirements for homeostatic regulation and behavioral integration. Many mechanistic insights have been provided by computational modeling studies driven by experimental results and have advanced understanding in the field. These conceptual and theoretical developments are discussed.
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Affiliation(s)
- Jeffrey C Smith
- Cellular and Systems Neurobiology Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, United States.
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15
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Pharmacological Modulation and (Patho)Physiological Roles of TRPM4 Channel-Part 2: TRPM4 in Health and Disease. Pharmaceuticals (Basel) 2021; 15:ph15010040. [PMID: 35056097 PMCID: PMC8779181 DOI: 10.3390/ph15010040] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Revised: 12/21/2021] [Accepted: 12/22/2021] [Indexed: 02/06/2023] Open
Abstract
Transient receptor potential melastatin 4 (TRPM4) is a unique member of the TRPM protein family and, similarly to TRPM5, is Ca2+ sensitive and permeable for monovalent but not divalent cations. It is widely expressed in many organs and is involved in several functions; it regulates membrane potential and Ca2+ homeostasis in both excitable and non-excitable cells. This part of the review discusses the currently available knowledge about the physiological and pathophysiological roles of TRPM4 in various tissues. These include the physiological functions of TRPM4 in the cells of the Langerhans islets of the pancreas, in various immune functions, in the regulation of vascular tone, in respiratory and other neuronal activities, in chemosensation, and in renal and cardiac physiology. TRPM4 contributes to pathological conditions such as overactive bladder, endothelial dysfunction, various types of malignant diseases and central nervous system conditions including stroke and injuries as well as in cardiac conditions such as arrhythmias, hypertrophy, and ischemia-reperfusion injuries. TRPM4 claims more and more attention and is likely to be the topic of research in the future.
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16
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Trpm5 channels encode bistability of spinal motoneurons and ensure motor control of hindlimbs in mice. Nat Commun 2021; 12:6815. [PMID: 34819493 PMCID: PMC8613399 DOI: 10.1038/s41467-021-27113-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2021] [Accepted: 11/02/2021] [Indexed: 11/09/2022] Open
Abstract
Bistable motoneurons of the spinal cord exhibit warmth-activated plateau potential driven by Na+ and triggered by a brief excitation. The thermoregulating molecular mechanisms of bistability and their role in motor functions remain unknown. Here, we identify thermosensitive Na+-permeable Trpm5 channels as the main molecular players for bistability in mouse motoneurons. Pharmacological, genetic or computational inhibition of Trpm5 occlude bistable-related properties (slow afterdepolarization, windup, plateau potentials) and reduce spinal locomotor outputs while central pattern generators for locomotion operate normally. At cellular level, Trpm5 is activated by a ryanodine-mediated Ca2+ release and turned off by Ca2+ reuptake through the sarco/endoplasmic reticulum Ca2+-ATPase (SERCA) pump. Mice in which Trpm5 is genetically silenced in most lumbar motoneurons develop hindlimb paresis and show difficulties in executing high-demanding locomotor tasks. Overall, by encoding bistability in motoneurons, Trpm5 appears indispensable for producing a postural tone in hindlimbs and amplifying the locomotor output.
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17
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Thompson B, Satin LS. Beta-Cell Ion Channels and Their Role in Regulating Insulin Secretion. Compr Physiol 2021; 11:1-21. [PMID: 34636409 PMCID: PMC8935893 DOI: 10.1002/cphy.c210004] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Beta cells of the pancreatic islet express many different types of ion channels. These channels reside in the β-cell plasma membrane as well as subcellular organelles and their coordinated activity and sensitivity to metabolism regulate glucose-dependent insulin secretion. Here, we review the molecular nature, expression patterns, and functional roles of many β-cell channels, with an eye toward explaining the ionic basis of glucose-induced insulin secretion. Our primary focus is on KATP and voltage-gated Ca2+ channels as these primarily regulate insulin secretion; other channels in our view primarily help to sculpt the electrical patterns generated by activated β-cells or indirectly regulate metabolism. Lastly, we discuss why understanding the physiological roles played by ion channels is important for understanding the secretory defects that occur in type 2 diabetes. © 2021 American Physiological Society. Compr Physiol 11:1-21, 2021.
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18
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Wang M, Sun Y, Li L, Wu P, Dkw O, Shi H. Calcium Channels: Noteworthy Regulators and Therapeutic Targets in Dermatological Diseases. Front Pharmacol 2021; 12:702264. [PMID: 34489697 PMCID: PMC8418299 DOI: 10.3389/fphar.2021.702264] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Accepted: 08/02/2021] [Indexed: 02/05/2023] Open
Abstract
Dysfunctional skin barrier and impaired skin homeostasis may lead to or aggravate a series of dermatologic diseases. A large variety of biological events and bioactive molecules are involved in the process of skin wound healing and functional recovery. Calcium ions (Ca2+) released from intracellular stores as well as influx through plasma membrane are essential to skin function. Growing evidence suggests that calcium influx is mainly regulated by calcium-sensing receptors and channels, including voltage-gated, transient potential receptor, store-operated, and receptor-operated calcium channels, which not only maintain cellular Ca2+ homeostasis, but also participate in cell proliferation and skin cell homeostasis through Ca2+-sensitive proteins such as calmodulin (CaM). Furthermore, distinct types of Ca2+ channels not merely work separately, they may work concertedly to regulate cell function. In this review, we discussed different calcium-sensing receptors and channels, including voltage-gated, transient receptor potential, store-operated, and receptor-operated calcium channels, particularly focusing on their regulatory functions and inherent interactions as well as calcium channels-related reagents and drugs, which is expected to bridge basic research and clinical applications in dermatologic diseases.
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Affiliation(s)
- Min Wang
- Jiangsu Key Laboratory of Medical Science and Laboratory Medicine, Institute of Stem Cell, School of Medicine, Jiangsu University, Zhenjiang, China
| | - Yaoxiang Sun
- Department of Clinical Laboratory, The Affiliated Yixing Hospital of Jiangsu University, Yixing, China
| | - Linli Li
- Jiangsu Key Laboratory of Medical Science and Laboratory Medicine, Institute of Stem Cell, School of Medicine, Jiangsu University, Zhenjiang, China
| | - Peipei Wu
- Jiangsu Key Laboratory of Medical Science and Laboratory Medicine, Institute of Stem Cell, School of Medicine, Jiangsu University, Zhenjiang, China
| | - Ocansey Dkw
- Jiangsu Key Laboratory of Medical Science and Laboratory Medicine, Institute of Stem Cell, School of Medicine, Jiangsu University, Zhenjiang, China.,Directorate of University Health Services, University of Cape Coast, Cape Coast, Ghana
| | - Hui Shi
- Jiangsu Key Laboratory of Medical Science and Laboratory Medicine, Institute of Stem Cell, School of Medicine, Jiangsu University, Zhenjiang, China
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19
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Dienes C, Hézső T, Kiss DZ, Baranyai D, Kovács ZM, Szabó L, Magyar J, Bányász T, Nánási PP, Horváth B, Gönczi M, Szentandrássy N. Electrophysiological Effects of the Transient Receptor Potential Melastatin 4 Channel Inhibitor (4-Chloro-2-(2-chlorophenoxy)acetamido) Benzoic Acid (CBA) in Canine Left Ventricular Cardiomyocytes. Int J Mol Sci 2021; 22:ijms22179499. [PMID: 34502410 PMCID: PMC8430982 DOI: 10.3390/ijms22179499] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Revised: 07/23/2021] [Accepted: 08/27/2021] [Indexed: 01/16/2023] Open
Abstract
Transient receptor potential melastatin 4 (TRPM4) plays an important role in many tissues, including pacemaker and conductive tissues of the heart, but much less is known about its electrophysiological role in ventricular myocytes. Our earlier results showed the lack of selectivity of 9-phenanthrol, so CBA ((4-chloro-2-(2-chlorophenoxy)acetamido) benzoic acid) was chosen as a new, potentially selective inhibitor. Goal: Our aim was to elucidate the effect and selectivity of CBA in canine left ventricular cardiomyocytes and to study the expression of TRPM4 in the canine heart. Experiments were carried out in enzymatically isolated canine left ventricular cardiomyocytes. Ionic currents were recorded with an action potential (AP) voltage-clamp technique in whole-cell configuration at 37 °C. An amount of 10 mM BAPTA was used in the pipette solution to exclude the potential activation of TRPM4 channels. AP was recorded with conventional sharp microelectrodes. CBA was used in 10 µM concentrations. Expression of TRPM4 protein in the heart was studied by Western blot. TRPM4 protein was expressed in the wall of all four chambers of the canine heart as well as in samples prepared from isolated left ventricular cells. CBA induced an approximately 9% reduction in AP duration measured at 75% and 90% of repolarization and decreased the short-term variability of APD90. Moreover, AP amplitude was increased and the maximal rates of phase 0 and 1 were reduced by the drug. In AP clamp measurements, CBA-sensitive current contained a short, early outward and mainly a long, inward current. Transient outward potassium current (Ito) and late sodium current (INa,L) were reduced by approximately 20% and 47%, respectively, in the presence of CBA, while L-type calcium and inward rectifier potassium currents were not affected. These effects of CBA were largely reversible upon washout. Based on our results, the CBA induced reduction of phase-1 slope and the slight increase of AP amplitude could have been due to the inhibition of Ito. The tendency for AP shortening can be explained by the inhibition of inward currents seen in AP-clamp recordings during the plateau phase. This inward current reduced by CBA is possibly INa,L, therefore, CBA is not entirely selective for TRPM4 channels. As a consequence, similarly to 9-phenanthrol, it cannot be used to test the contribution of TRPM4 channels to cardiac electrophysiology in ventricular cells, or at least caution must be applied.
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Affiliation(s)
- Csaba Dienes
- Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary; (C.D.); (T.H.); (D.Z.K.); (D.B.); (Z.M.K.); (L.S.); (J.M.); (T.B.); (P.P.N.); (B.H.); (M.G.)
- Doctoral School of Molecular Medicine, University of Debrecen, 4032 Debrecen, Hungary
| | - Tamás Hézső
- Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary; (C.D.); (T.H.); (D.Z.K.); (D.B.); (Z.M.K.); (L.S.); (J.M.); (T.B.); (P.P.N.); (B.H.); (M.G.)
- Doctoral School of Molecular Medicine, University of Debrecen, 4032 Debrecen, Hungary
| | - Dénes Zsolt Kiss
- Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary; (C.D.); (T.H.); (D.Z.K.); (D.B.); (Z.M.K.); (L.S.); (J.M.); (T.B.); (P.P.N.); (B.H.); (M.G.)
- Doctoral School of Molecular Medicine, University of Debrecen, 4032 Debrecen, Hungary
| | - Dóra Baranyai
- Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary; (C.D.); (T.H.); (D.Z.K.); (D.B.); (Z.M.K.); (L.S.); (J.M.); (T.B.); (P.P.N.); (B.H.); (M.G.)
- Doctoral School of Molecular Medicine, University of Debrecen, 4032 Debrecen, Hungary
| | - Zsigmond Máté Kovács
- Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary; (C.D.); (T.H.); (D.Z.K.); (D.B.); (Z.M.K.); (L.S.); (J.M.); (T.B.); (P.P.N.); (B.H.); (M.G.)
- Doctoral School of Molecular Medicine, University of Debrecen, 4032 Debrecen, Hungary
| | - László Szabó
- Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary; (C.D.); (T.H.); (D.Z.K.); (D.B.); (Z.M.K.); (L.S.); (J.M.); (T.B.); (P.P.N.); (B.H.); (M.G.)
- Doctoral School of Molecular Medicine, University of Debrecen, 4032 Debrecen, Hungary
| | - János Magyar
- Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary; (C.D.); (T.H.); (D.Z.K.); (D.B.); (Z.M.K.); (L.S.); (J.M.); (T.B.); (P.P.N.); (B.H.); (M.G.)
- Division of Sport Physiology, Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary
| | - Tamás Bányász
- Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary; (C.D.); (T.H.); (D.Z.K.); (D.B.); (Z.M.K.); (L.S.); (J.M.); (T.B.); (P.P.N.); (B.H.); (M.G.)
| | - Péter P. Nánási
- Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary; (C.D.); (T.H.); (D.Z.K.); (D.B.); (Z.M.K.); (L.S.); (J.M.); (T.B.); (P.P.N.); (B.H.); (M.G.)
- Department of Dental Physiology and Pharmacology, Faculty of Dentistry, University of Debrecen, 4032 Debrecen, Hungary
| | - Balázs Horváth
- Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary; (C.D.); (T.H.); (D.Z.K.); (D.B.); (Z.M.K.); (L.S.); (J.M.); (T.B.); (P.P.N.); (B.H.); (M.G.)
- Faculty of Pharmacy, University of Debrecen, 4032 Debrecen, Hungary
| | - Mónika Gönczi
- Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary; (C.D.); (T.H.); (D.Z.K.); (D.B.); (Z.M.K.); (L.S.); (J.M.); (T.B.); (P.P.N.); (B.H.); (M.G.)
| | - Norbert Szentandrássy
- Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary; (C.D.); (T.H.); (D.Z.K.); (D.B.); (Z.M.K.); (L.S.); (J.M.); (T.B.); (P.P.N.); (B.H.); (M.G.)
- Department of Basic Medical Sciences, Faculty of Dentistry, University of Debrecen, 4032 Debrecen, Hungary
- Correspondence: ; Tel.: +36-52255575; Fax: +36-52255116
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Ruan Z, Haley E, Orozco IJ, Sabat M, Myers R, Roth R, Du J, Lü W. Structures of the TRPM5 channel elucidate mechanisms of activation and inhibition. Nat Struct Mol Biol 2021; 28:604-613. [PMID: 34168372 PMCID: PMC8767786 DOI: 10.1038/s41594-021-00607-4] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Accepted: 05/12/2021] [Indexed: 02/06/2023]
Abstract
The Ca2+-activated TRPM5 channel plays essential roles in taste perception and insulin secretion. However, the mechanism by which Ca2+ regulates TRPM5 activity remains elusive. We report cryo-EM structures of the zebrafish TRPM5 in an apo closed state, a Ca2+-bound open state, and an antagonist-bound inhibited state. We define two novel ligand binding sites: a Ca2+ site (CaICD) in the intracellular domain and an antagonist site in the transmembrane domain (TMD). The CaICD site is unique to TRPM5 and has two roles: modulating the voltage dependence and promoting Ca2+ binding to the CaTMD site, which is conserved throughout TRPM channels. Conformational changes initialized from both Ca2+ sites cooperatively open the ion-conducting pore. The antagonist NDNA wedges into the space between the S1-S4 domain and pore domain, stabilizing the transmembrane domain in an apo-like closed state. Our results lay the foundation for understanding the voltage-dependent TRPM channels and developing new therapeutic agents.
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Affiliation(s)
- Zheng Ruan
- Van Andel Institute, 333 Bostwick Ave., N.E., Grand Rapids, MI 49503
| | - Emery Haley
- Van Andel Institute, 333 Bostwick Ave., N.E., Grand Rapids, MI 49503
| | - Ian J. Orozco
- Van Andel Institute, 333 Bostwick Ave., N.E., Grand Rapids, MI 49503
| | - Mark Sabat
- Takeda California Inc, 9625 Towne Centre Dr, San Diego, CA 92121
| | - Richard Myers
- Takeda California Inc, 9625 Towne Centre Dr, San Diego, CA 92121
| | - Rebecca Roth
- Van Andel Institute, 333 Bostwick Ave., N.E., Grand Rapids, MI 49503
| | - Juan Du
- Van Andel Institute, 333 Bostwick Ave., N.E., Grand Rapids, MI 49503,CORRESPONDING AUTHOR: Correspondence and requests for materials should be addressed to J. D. () TEL: (616) 234-5358, FAX: 616-234-5170 or W. L. (). TEL: (616) 234-5022, FAX: 616-234-5170
| | - Wei Lü
- Van Andel Institute, 333 Bostwick Ave., N.E., Grand Rapids, MI 49503,CORRESPONDING AUTHOR: Correspondence and requests for materials should be addressed to J. D. () TEL: (616) 234-5358, FAX: 616-234-5170 or W. L. (). TEL: (616) 234-5022, FAX: 616-234-5170
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21
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Shi R, Fu Y, Zhao D, Boczek T, Wang W, Guo F. Cell death modulation by transient receptor potential melastatin channels TRPM2 and TRPM7 and their underlying molecular mechanisms. Biochem Pharmacol 2021; 190:114664. [PMID: 34175300 DOI: 10.1016/j.bcp.2021.114664] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 06/21/2021] [Accepted: 06/22/2021] [Indexed: 10/21/2022]
Abstract
Transient receptor potential melastatin (TRPM) channels are members of the transient receptor potential (TRP) channels, a family of evolutionarily conserved integral membrane proteins. TRPM channels are nonselective cation channels, mediating the influx of various ions including Ca2+, Na+ and Zn2+. The function of TRPM channels is vital for cell proliferation, cell development and cell death. Cell death is a key procedure during embryonic development, organism homeostasis, aging and disease. The category of cell death modalities, beyond the traditionally defined concepts of necrosis, autophagy, and apoptosis, were extended with the discovery of pyroptosis, necroptosis and ferroptosis. As upstream signaling regulators of cell death, TRPM channels have been involved inrelevant pathologies. In this review, we introduced several cell death modalities, then summarized the contribution of TRPM channels (especially TRPM2 and TRPM7) to different cell death modalities and discussed the underlying regulatory mechanisms. Our work highlighted the possibility of TRPM channels as potential therapeutic targets in cell death-related diseases.
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Affiliation(s)
- Ruixue Shi
- Department of Pharmaceutical Toxicology, School of Pharmacy, China Medical University, Shenyang 110122, China
| | - Yu Fu
- Department of Pharmaceutical Toxicology, School of Pharmacy, China Medical University, Shenyang 110122, China
| | - Dongyi Zhao
- The University of Tokyo, Department of Pharmaceutical Science, 1130033, Japan
| | - Tomasz Boczek
- Department of Molecular Neurochemistry, Medical University of Lodz, 92215, Poland.
| | - Wuyang Wang
- Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical University, Xuzhou 221004, China.
| | - Feng Guo
- Department of Pharmaceutical Toxicology, School of Pharmacy, China Medical University, Shenyang 110122, China.
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22
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Sakaguchi T, Okumura R, Ono C, Okuzaki D, Kawai T, Okochi Y, Tanimura N, Murakami M, Kayama H, Umemoto E, Kioka H, Ohtani T, Sakata Y, Miyake K, Okamura Y, Baba Y, Takeda K. TRPM5 Negatively Regulates Calcium-Dependent Responses in Lipopolysaccharide-Stimulated B Lymphocytes. Cell Rep 2021; 31:107755. [PMID: 32521253 DOI: 10.1016/j.celrep.2020.107755] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2019] [Revised: 03/16/2020] [Accepted: 05/20/2020] [Indexed: 12/15/2022] Open
Abstract
B cells produce high amounts of cytokines and immunoglobulins in response to lipopolysaccharide (LPS) stimulation. Calcium signaling cascades are critically involved in cytokine production of T cells, and the cytosolic calcium concentration is regulated by calcium-activated monovalent cation channels (CAMs). Calcium signaling is also implicated in B cell activation; however, its involvement in the cytokine production of LPS-stimulated B cells remains less well characterized. Here, we show that the transient receptor potential melastatin 5 channel (TRPM5), which is one of the CAMs, negatively modulates calcium signaling, thereby regulating LPS-induced proliferative and inflammatory responses by B cells. LPS-stimulated B cells of Trpm5-deficient mice exhibit an increased cytosolic calcium concentration, leading to enhanced proliferation and the production of the inflammatory cytokines interleukin-6 and CXCL10. Furthermore, Trpm5-deficient mice show an exacerbation of endotoxic shock with high mortality. Our findings demonstrate the importance of TRPM5-dependent regulatory mechanisms in LPS-induced calcium signaling of splenic B cells.
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Affiliation(s)
- Taiki Sakaguchi
- Laboratory of Immune Regulation, Department of Microbiology and Immunology, Graduate School of Medicine, Osaka University, Suita, Japan; WPI Immunology Frontier Research Center, Osaka University, Suita, Japan; Department of Cardiovascular Medicine, Graduate School of Medicine, Osaka University, Suita, Japan
| | - Ryu Okumura
- Laboratory of Immune Regulation, Department of Microbiology and Immunology, Graduate School of Medicine, Osaka University, Suita, Japan; WPI Immunology Frontier Research Center, Osaka University, Suita, Japan
| | - Chisato Ono
- Division of Immunology and Genome Biology, Medical Institute of Bioregulation, Kyushu University, Fukuoka, Japan
| | - Daisuke Okuzaki
- Genome Information Research Center, Research Institute for Microbial Diseases, Osaka University, Suita, Japan; Integrated Frontier Research for Medical Science Division, Institute for Open and Transdisciplinary Research Initiatives, Osaka University, Suita, Japan
| | - Takafumi Kawai
- Laboratory of Integrative Physiology, Department of Physiology, Graduate School of Medicine, Osaka University, Suita, Japan
| | - Yoshifumi Okochi
- Laboratory of Integrative Physiology, Department of Physiology, Graduate School of Medicine, Osaka University, Suita, Japan
| | - Natsuko Tanimura
- Department of Pharmacology, Tokyo Women's Medical University School of Medicine, Tokyo, Japan
| | - Mari Murakami
- Laboratory of Immune Regulation, Department of Microbiology and Immunology, Graduate School of Medicine, Osaka University, Suita, Japan; WPI Immunology Frontier Research Center, Osaka University, Suita, Japan
| | - Hisako Kayama
- Laboratory of Immune Regulation, Department of Microbiology and Immunology, Graduate School of Medicine, Osaka University, Suita, Japan; WPI Immunology Frontier Research Center, Osaka University, Suita, Japan; Institute for Advanced Co-Creation Studies, Osaka University, Suita, Japan
| | - Eiji Umemoto
- Laboratory of Immune Regulation, Department of Microbiology and Immunology, Graduate School of Medicine, Osaka University, Suita, Japan; WPI Immunology Frontier Research Center, Osaka University, Suita, Japan
| | - Hidetaka Kioka
- Department of Cardiovascular Medicine, Graduate School of Medicine, Osaka University, Suita, Japan
| | - Tomohito Ohtani
- Department of Cardiovascular Medicine, Graduate School of Medicine, Osaka University, Suita, Japan
| | - Yasushi Sakata
- Department of Cardiovascular Medicine, Graduate School of Medicine, Osaka University, Suita, Japan
| | - Kensuke Miyake
- Division of Innate Immunity, Department of Microbiology and Immunology, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - Yasushi Okamura
- Laboratory of Integrative Physiology, Department of Physiology, Graduate School of Medicine, Osaka University, Suita, Japan
| | - Yoshihiro Baba
- Division of Immunology and Genome Biology, Medical Institute of Bioregulation, Kyushu University, Fukuoka, Japan
| | - Kiyoshi Takeda
- Laboratory of Immune Regulation, Department of Microbiology and Immunology, Graduate School of Medicine, Osaka University, Suita, Japan; WPI Immunology Frontier Research Center, Osaka University, Suita, Japan; Integrated Frontier Research for Medical Science Division, Institute for Open and Transdisciplinary Research Initiatives, Osaka University, Suita, Japan.
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23
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Barilli A, Aldegheri L, Bianchi F, Brault L, Brodbeck D, Castelletti L, Feriani A, Lingard I, Myers R, Nola S, Piccoli L, Pompilio D, Raveglia LF, Salvagno C, Tassini S, Virginio C, Sabat M. From High-Throughput Screening to Target Validation: Benzo[ d]isothiazoles as Potent and Selective Agonists of Human Transient Receptor Potential Cation Channel Subfamily M Member 5 Possessing In Vivo Gastrointestinal Prokinetic Activity in Rodents. J Med Chem 2021; 64:5931-5955. [PMID: 33890770 DOI: 10.1021/acs.jmedchem.1c00065] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Transient receptor potential cation channel subfamily M member 5 (TRPM5) is a nonselective monovalent cation channel activated by intracellular Ca2+ increase. Within the gastrointestinal system, TRPM5 is expressed in the stoma, small intestine, and colon. In the search for a selective agonist of TRPM5 possessing in vivo gastrointestinal prokinetic activity, a high-throughput screening was performed and compound 1 was identified as a promising hit. Hit validation and hit to lead activities led to the discovery of a series of benzo[d]isothiazole derivatives. Among these, compounds 61 and 64 showed nanomolar activity and excellent selectivity (>100-fold) versus related cation channels. The in vivo drug metabolism and pharmacokinetic profile of compound 64 was found to be ideal for a compound acting locally at the intestinal level, with minimal absorption into systemic circulation. Compound 64 was tested in vivo in a mouse motility assay at 100 mg/kg, and demonstrated increased prokinetic activity.
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Affiliation(s)
- Alessio Barilli
- Aptuit, an Evotec Company, Via Alessandro Fleming, 4, Verona 37135, Italy
| | - Laura Aldegheri
- Aptuit, an Evotec Company, Via Alessandro Fleming, 4, Verona 37135, Italy
| | - Federica Bianchi
- Aptuit, an Evotec Company, Via Alessandro Fleming, 4, Verona 37135, Italy
| | - Laurent Brault
- Aptuit, an Evotec Company, Via Alessandro Fleming, 4, Verona 37135, Italy
| | - Daniela Brodbeck
- Aptuit, an Evotec Company, Via Alessandro Fleming, 4, Verona 37135, Italy
| | - Laura Castelletti
- Aptuit, an Evotec Company, Via Alessandro Fleming, 4, Verona 37135, Italy
| | - Aldo Feriani
- Aptuit, an Evotec Company, Via Alessandro Fleming, 4, Verona 37135, Italy
| | - Iain Lingard
- Aptuit, an Evotec Company, Via Alessandro Fleming, 4, Verona 37135, Italy
| | - Richard Myers
- Takeda Pharmaceuticals, 9625 Towne Centre Drive, San Diego, California 92121, United States
| | - Selena Nola
- Aptuit, an Evotec Company, Via Alessandro Fleming, 4, Verona 37135, Italy
| | - Laura Piccoli
- Aptuit, an Evotec Company, Via Alessandro Fleming, 4, Verona 37135, Italy
| | - Daniela Pompilio
- Aptuit, an Evotec Company, Via Alessandro Fleming, 4, Verona 37135, Italy
| | - Luca F Raveglia
- Aptuit, an Evotec Company, Via Alessandro Fleming, 4, Verona 37135, Italy
| | - Cristian Salvagno
- Aptuit, an Evotec Company, Via Alessandro Fleming, 4, Verona 37135, Italy
| | - Sabrina Tassini
- Aptuit, an Evotec Company, Via Alessandro Fleming, 4, Verona 37135, Italy
| | - Caterina Virginio
- Aptuit, an Evotec Company, Via Alessandro Fleming, 4, Verona 37135, Italy
| | - Mark Sabat
- Takeda Pharmaceuticals, 9625 Towne Centre Drive, San Diego, California 92121, United States
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24
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Hariharan A, Weir N, Robertson C, He L, Betsholtz C, Longden TA. The Ion Channel and GPCR Toolkit of Brain Capillary Pericytes. Front Cell Neurosci 2020; 14:601324. [PMID: 33390906 PMCID: PMC7775489 DOI: 10.3389/fncel.2020.601324] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Accepted: 11/13/2020] [Indexed: 12/14/2022] Open
Abstract
Brain pericytes reside on the abluminal surface of capillaries, and their processes cover ~90% of the length of the capillary bed. These cells were first described almost 150 years ago (Eberth, 1871; Rouget, 1873) and have been the subject of intense experimental scrutiny in recent years, but their physiological roles remain uncertain and little is known of the complement of signaling elements that they employ to carry out their functions. In this review, we synthesize functional data with single-cell RNAseq screens to explore the ion channel and G protein-coupled receptor (GPCR) toolkit of mesh and thin-strand pericytes of the brain, with the aim of providing a framework for deeper explorations of the molecular mechanisms that govern pericyte physiology. We argue that their complement of channels and receptors ideally positions capillary pericytes to play a central role in adapting blood flow to meet the challenge of satisfying neuronal energy requirements from deep within the capillary bed, by enabling dynamic regulation of their membrane potential to influence the electrical output of the cell. In particular, we outline how genetic and functional evidence suggest an important role for Gs-coupled GPCRs and ATP-sensitive potassium (KATP) channels in this context. We put forth a predictive model for long-range hyperpolarizing electrical signaling from pericytes to upstream arterioles, and detail the TRP and Ca2+ channels and Gq, Gi/o, and G12/13 signaling processes that counterbalance this. We underscore critical questions that need to be addressed to further advance our understanding of the signaling topology of capillary pericytes, and how this contributes to their physiological roles and their dysfunction in disease.
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Affiliation(s)
- Ashwini Hariharan
- Department of Physiology, School of Medicine, University of Maryland, Baltimore, MD, United States
| | - Nick Weir
- Department of Physiology, School of Medicine, University of Maryland, Baltimore, MD, United States
| | - Colin Robertson
- Department of Physiology, School of Medicine, University of Maryland, Baltimore, MD, United States
| | - Liqun He
- Rudbeck Laboratory, Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala, Sweden
| | - Christer Betsholtz
- Rudbeck Laboratory, Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala, Sweden.,Department of Medicine Huddinge (MedH), Karolinska Institutet & Integrated Cardio Metabolic Centre, Huddinge, Sweden
| | - Thomas A Longden
- Department of Physiology, School of Medicine, University of Maryland, Baltimore, MD, United States
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25
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Jimenez I, Prado Y, Marchant F, Otero C, Eltit F, Cabello-Verrugio C, Cerda O, Simon F. TRPM Channels in Human Diseases. Cells 2020; 9:E2604. [PMID: 33291725 PMCID: PMC7761947 DOI: 10.3390/cells9122604] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Revised: 11/30/2020] [Accepted: 12/01/2020] [Indexed: 12/11/2022] Open
Abstract
The transient receptor potential melastatin (TRPM) subfamily belongs to the TRP cation channels family. Since the first cloning of TRPM1 in 1989, tremendous progress has been made in identifying novel members of the TRPM subfamily and their functions. The TRPM subfamily is composed of eight members consisting of four six-transmembrane domain subunits, resulting in homomeric or heteromeric channels. From a structural point of view, based on the homology sequence of the coiled-coil in the C-terminus, the eight TRPM members are clustered into four groups: TRPM1/M3, M2/M8, M4/M5 and M6/M7. TRPM subfamily members have been involved in several physiological functions. However, they are also linked to diverse pathophysiological human processes. Alterations in the expression and function of TRPM subfamily ion channels might generate several human diseases including cardiovascular and neurodegenerative alterations, organ dysfunction, cancer and many other channelopathies. These effects position them as remarkable putative targets for novel diagnostic strategies, drug design and therapeutic approaches. Here, we review the current knowledge about the main characteristics of all members of the TRPM family, focusing on their actions in human diseases.
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Affiliation(s)
- Ivanka Jimenez
- Faculty of Life Science, Universidad Andrés Bello, Santiago 8370186, Chile; (I.J.); (Y.P.); (F.M.); (C.C.-V.)
- Millennium Nucleus of Ion Channel-Associated Diseases (MiNICAD), Universidad de Chile, Santiago 8380453, Chile;
| | - Yolanda Prado
- Faculty of Life Science, Universidad Andrés Bello, Santiago 8370186, Chile; (I.J.); (Y.P.); (F.M.); (C.C.-V.)
- Millennium Nucleus of Ion Channel-Associated Diseases (MiNICAD), Universidad de Chile, Santiago 8380453, Chile;
| | - Felipe Marchant
- Faculty of Life Science, Universidad Andrés Bello, Santiago 8370186, Chile; (I.J.); (Y.P.); (F.M.); (C.C.-V.)
- Millennium Nucleus of Ion Channel-Associated Diseases (MiNICAD), Universidad de Chile, Santiago 8380453, Chile;
| | - Carolina Otero
- Faculty of Medicine, School of Chemistry and Pharmacy, Universidad Andrés Bello, Santiago 8370186, Chile;
| | - Felipe Eltit
- Vancouver Prostate Centre, Vancouver, BC V6Z 1Y6, Canada;
- Department of Urological Sciences, University of British Columbia, Vancouver, BC V6Z 1Y6, Canada
| | - Claudio Cabello-Verrugio
- Faculty of Life Science, Universidad Andrés Bello, Santiago 8370186, Chile; (I.J.); (Y.P.); (F.M.); (C.C.-V.)
- Center for the Development of Nanoscience and Nanotechnology (CEDENNA), Universidad de Santiago de Chile, Santiago 7560484, Chile
- Millennium Institute on Immunology and Immunotherapy, Santiago 8370146, Chile
| | - Oscar Cerda
- Millennium Nucleus of Ion Channel-Associated Diseases (MiNICAD), Universidad de Chile, Santiago 8380453, Chile;
- Program of Cellular and Molecular Biology, Institute of Biomedical Sciences (ICBM), Faculty of Medicine, Universidad de Chile, Santiago 8380453, Chile
| | - Felipe Simon
- Faculty of Life Science, Universidad Andrés Bello, Santiago 8370186, Chile; (I.J.); (Y.P.); (F.M.); (C.C.-V.)
- Millennium Nucleus of Ion Channel-Associated Diseases (MiNICAD), Universidad de Chile, Santiago 8380453, Chile;
- Millennium Institute on Immunology and Immunotherapy, Santiago 8370146, Chile
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26
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Jeruzal-Świątecka J, Fendler W, Pietruszewska W. Clinical Role of Extraoral Bitter Taste Receptors. Int J Mol Sci 2020; 21:E5156. [PMID: 32708215 PMCID: PMC7404188 DOI: 10.3390/ijms21145156] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 07/15/2020] [Accepted: 07/16/2020] [Indexed: 12/15/2022] Open
Abstract
Humans can recognise five basic tastes: sweet, sour, salty, bitter and umami. Sour and salty substances are linked to ion channels, while sweet, bitter and umami flavours are transmitted through receptors linked to the G protein (G protein-coupled receptors; GPCRs). There are two main types of GPCRs that transmit information about sweet, umami and bitter tastes-the Tas1r and TAS2R families. There are about 25 functional TAS2R genes coding bitter taste receptor proteins. They are found not only in the mouth and throat, but also in the intestines, brain, bladder and lower and upper respiratory tract. The determination of their purpose in these locations has become an inspiration for much research. Their presence has also been confirmed in breast cancer cells, ovarian cancer cells and neuroblastoma, revealing a promising new oncological marker. Polymorphisms of TAS2R38 have been proven to have an influence on the course of chronic rhinosinusitis and upper airway defensive mechanisms. TAS2R receptors mediate the bronchodilatory effect in human airway smooth muscle, which may lead to the creation of another medicine group used in asthma or chronic obstructive pulmonary disease. The discovery that functionally compromised TAS2R receptors negatively impact glucose homeostasis has produced a new area of diabetes research. In this article, we would like to focus on what facts have been already established in the matter of extraoral TAS2R receptors in humans.
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Affiliation(s)
- Joanna Jeruzal-Świątecka
- Department of Otolaryngology, Head and Neck Oncology, Medical University of Lodz, 90-419 Lodz, Poland;
| | - Wojciech Fendler
- Department of Biostatistics and Translational Medicine, Medical University of Lodz, 90-419 Lodz, Poland;
- Department of Radiation Oncology, Dana-Farber Cancer Institute, Boston, MA 02115, USA
| | - Wioletta Pietruszewska
- Department of Otolaryngology, Head and Neck Oncology, Medical University of Lodz, 90-419 Lodz, Poland;
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27
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Fat taste signal transduction and its possible negative modulator components. Prog Lipid Res 2020; 79:101035. [DOI: 10.1016/j.plipres.2020.101035] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Revised: 04/26/2020] [Accepted: 04/29/2020] [Indexed: 02/07/2023]
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28
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López-Romero AE, Hernández-Araiza I, Torres-Quiroz F, Tovar-Y-Romo LB, Islas LD, Rosenbaum T. TRP ion channels: Proteins with conformational flexibility. Channels (Austin) 2020; 13:207-226. [PMID: 31184289 PMCID: PMC6602575 DOI: 10.1080/19336950.2019.1626793] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Ion channels display conformational changes in response to binding of their agonists and antagonists. The study of the relationships between the structure and the function of these proteins has witnessed considerable advances in the last two decades using a combination of techniques, which include electrophysiology, optical approaches (i.e. patch clamp fluorometry, incorporation of non-canonic amino acids, etc.), molecular biology (mutations in different regions of ion channels to determine their role in function) and those that have permitted the resolution of their structures in detail (X-ray crystallography and cryo-electron microscopy). The possibility of making correlations among structural components and functional traits in ion channels has allowed for more refined conclusions on how these proteins work at the molecular level. With the cloning and description of the family of Transient Receptor Potential (TRP) channels, our understanding of several sensory-related processes has also greatly moved forward. The response of these proteins to several agonists, their regulation by signaling pathways as well as by protein-protein and lipid-protein interactions and, in some cases, their biophysical characteristics have been studied thoroughly and, recently, with the resolution of their structures, the field has experienced a new boom. This review article focuses on the conformational changes in the pores, concentrating on some members of the TRP family of ion channels (TRPV and TRPA subfamilies) that result in changes in their single-channel conductances, a phenomenon that may lead to fine-tuning the electrical response to a given agonist in a cell.
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Affiliation(s)
- Ana Elena López-Romero
- a Departamento de Neurociencia Cognitiva, División Neurociencias , Instituto de Fisiología Celular, Universidad Nacional Autónoma de México , Mexico , Mexico
| | - Ileana Hernández-Araiza
- a Departamento de Neurociencia Cognitiva, División Neurociencias , Instituto de Fisiología Celular, Universidad Nacional Autónoma de México , Mexico , Mexico
| | - Francisco Torres-Quiroz
- b Departamento de Bioquímica y Biología Estructural, División Investigación Básica , Instituto de Fisiología Celular, Universidad Nacional Autónoma de México , Mexico City , Mexico
| | - Luis B Tovar-Y-Romo
- c Departamento de Neuropatología Molecular, División Neurociencias , Instituto de Fisiología Celular, Universidad Nacional Autónoma de México , Mexico City , Mexico
| | - León D Islas
- d Departamento de Fisiología, Facultad de Medicina , Universidad Nacional Autónoma de México , Mexico City , Mexico
| | - Tamara Rosenbaum
- a Departamento de Neurociencia Cognitiva, División Neurociencias , Instituto de Fisiología Celular, Universidad Nacional Autónoma de México , Mexico , Mexico
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29
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Frede W, Medert R, Poth T, Gorenflo M, Vennekens R, Freichel M, Uhl S. TRPM4 Modulates Right Ventricular Remodeling Under Pressure Load Accompanied With Decreased Expression Level. J Card Fail 2020; 26:599-609. [PMID: 32147520 DOI: 10.1016/j.cardfail.2020.02.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2019] [Revised: 02/06/2020] [Accepted: 02/19/2020] [Indexed: 10/24/2022]
Abstract
BACKGROUND Survival of patients with congenital heart defects including increased right ventricular pressure load (ie, tetralogy of Fallot) or pulmonary hypertension is dependent on the function of the right ventricle (RV). RV remodeling has several effects with progressive transition from compensated status to heart failure. Transient receptor potential melastatin 4 (TRPM4) forms cation channels expressed in myocardium, which was shown to modulate cardiac remodeling in the left ventricle of mice. Aim of this study was to identify the role of TRPM4 for contractile function and remodeling of the RV in a rat model of right ventricular pressure load. METHODS AND RESULTS We performed experiments with untreated rats and under monocrotaline (MCT)-induced pressure load comparing wild-type (Trpm4+/+) and TRPM4-deficient (Trpm4-/-) rats. RV function was characterized by echocardiography and contractility measurements of isolated papillary muscles. RV hypertrophy was investigated by echocardiography and by determination of hypertrophy indices. Pulmonary arterial remodeling was evaluated by echocardiography and histology. TRPM4 protein expression in RV of human, rat and mouse was detected by Western blot and quantified in rat. TRPM4 proteins were detected in RV myocardium of rat and mouse, which were not detectable in TRPM4-deficient animals. Proteins of the same size were found in RV of a pediatric patient with tetralogy of Fallot. In untreated status, Trpm4+/+ and Trpm4-/- rats showed comparable RV contractile function and dimensions. Under pressure load (42 days after MCT injection), RV hypertrophy was significantly increased in Trpm4-/- rats compared with Trpm4+/+ controls, whereas MCT-mediated alterations in cardiac contractility and pulmonary arterial remodeling were not affected by TRPM4 inactivation in rats. Finally, TRPM4 protein expression in RV was drastically reduced in MCT-treated rats, whereas left ventricle of the same animals showed no alteration in TRPM4 expression. CONCLUSIONS Right ventricular pressure load evoked by MCT treatment in rats leads to a prominent downregulation of TRPM4 protein expression in the RV and complete deletion of TRPM4 expression aggravates right ventricular hypertrophy. Thus, therapeutic modulation of TRPM4 expression and activity might represent a novel approach to target right ventricular remodeling in patients with pulmonary hypertension or otherwise loaded RV.
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Affiliation(s)
- Wiebke Frede
- Department Pediatric and Congenital Cardiology, University Medical Center, Heidelberg, Germany; Institute of Pharmacology, University Medical Center, Heidelberg, Germany
| | - Rebekka Medert
- Institute of Pharmacology, University Medical Center, Heidelberg, Germany
| | - Tanja Poth
- Center for Model System and Comparative Pathology, University Medical Center, Heidelberg, Germany
| | - Matthias Gorenflo
- Department Pediatric and Congenital Cardiology, University Medical Center, Heidelberg, Germany
| | - Rudi Vennekens
- Laboratory of Ion Channel Research, Department of Cellular and Molecular Medicine, KU Leuven, Leuven, Vlaams Brabant, Belgium
| | - Marc Freichel
- Institute of Pharmacology, University Medical Center, Heidelberg, Germany
| | - Sebastian Uhl
- Department Pediatric and Congenital Cardiology, University Medical Center, Heidelberg, Germany; Institute of Pharmacology, University Medical Center, Heidelberg, Germany.
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30
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Malysz J, Maxwell SE, Yarotskyy V, Petkov GV. TRPM4 channel inhibitors 9-phenanthrol and glibenclamide differentially decrease guinea pig detrusor smooth muscle whole-cell cation currents and phasic contractions. Am J Physiol Cell Physiol 2020; 318:C406-C421. [PMID: 31851526 DOI: 10.1152/ajpcell.00055.2019] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Nonselective cation channels, consistent with transient receptor potential melastatin-4 (TRPM4), regulate detrusor smooth muscle (DSM) function. TRPM4 channels can exist as homomers or assemble with sulfonylurea receptors (SURs) as complexes. We evaluated contributions of TRPM4/SUR-TRPM4 channels to DSM excitability and contractility by examining the effects of TRPM4/SUR-TRPM4 channel modulators 9-phenanthrol, glibenclamide, and diazoxide on freshly-isolated guinea pig DSM cells (amphotericin-B perforated patch-clamp electrophysiology) and mucosa-free DSM strips (isometric tension recordings). In DSM cells, complete removal of extracellular Na+ decreased voltage-step-induced cation (non-K+ selective) currents. At high positive membrane potentials, 9-phenanthrol at 100 μM attenuated voltage step-induced currents more effectively than at 30 μM, revealing concentration-dependent, voltage-sensitive inhibition. In comparison to 9-phenanthrol, glibenclamide (100 μM) displayed lower inhibition of cation currents. In the presence of glibenclamide (100 μM), 9-phenanthrol (100 μM) further decreased the currents. The SUR-TRPM4 complex activator diazoxide (100-300 μM) weakly inhibited the currents. 9-Phenanthrol, but not glibenclamide or diazoxide, increased cell capacitance (a cell surface area indicator). In contractility studies, glibenclamide displayed lower potencies than 9-phenanthrol attenuating spontaneous and 20 mM KCl-induced DSM phasic contractions. While both compounds showed similar maximum inhibitions on DSM spontaneous phasic contractions, glibenclamide was generally less efficacious on 20 mM KCl-induced phasic contractions. In summary, the observed differential effects of 9-phenanthrol and glibenclamide on DSM excitability and contractility support unique mechanisms for the two compounds. The data suggest that SUR-TRPM4 complexes do not contribute to DSM function. This study advances our understanding of pharmacological effects of glibenclamide and 9-phenanthrol on DSM cell cation currents.
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Affiliation(s)
- John Malysz
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, Tennessee
| | - Sarah E Maxwell
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, Tennessee
| | - Viktor Yarotskyy
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, Tennessee
| | - Georgi V Petkov
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, Tennessee
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31
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Xian W, Hui X, Tian Q, Wang H, Moretti A, Laugwitz KL, Flockerzi V, Ruppenthal S, Lipp P. Aberrant Deactivation-Induced Gain of Function in TRPM4 Mutant Is Associated with Human Cardiac Conduction Block. Cell Rep 2019; 24:724-731. [PMID: 30021168 DOI: 10.1016/j.celrep.2018.06.034] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Revised: 02/27/2018] [Accepted: 06/07/2018] [Indexed: 02/04/2023] Open
Abstract
A gain-of-function mutation in the Ca2+-activated transient receptor potential melastatin member 4 (TRPM4A432T) is linked to life-threatening cardiac conduction disturbance, but the underlying mechanism is unclear. For deeper insights, we used photolysis of caged Ca2+, quantitative Ca2+, and electrophysiological measurements. TRPM4A432T's 2-fold larger membrane current was associated with 50% decreased plasma membrane expression. Kinetic analysis unveiled 4-fold slower deactivation that was responsible for the augmented membrane current progressively rising during repetitive human cardiac action potentials. Rational mutagenesis of TRPM4 at position 432 revealed that the bulkiness of the amino acid was key to TRPM4A432T's aberrant gating. Charged amino acids rendered the channel non-functional. The slow deactivation caused by an amino acid substitution at position 432 from alanine to the bulkier threonine represents a key contributor to the gain of function in TRPM4A432T. Thus, our results add a mechanism in the etiology of TRP channel-linked human cardiac channelopathies.
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Affiliation(s)
- Wenying Xian
- Molecular Cell Biology, Centre for Molecular Signaling (PZMS), Medical Faculty, Saarland University, 66421 Homburg, Germany
| | - Xin Hui
- Molecular Cell Biology, Centre for Molecular Signaling (PZMS), Medical Faculty, Saarland University, 66421 Homburg, Germany
| | - Qinghai Tian
- Molecular Cell Biology, Centre for Molecular Signaling (PZMS), Medical Faculty, Saarland University, 66421 Homburg, Germany
| | - Hongmei Wang
- Experimental and Clinical Pharmacology and Toxicology, Centre for Molecular Signaling (PZMS), Medical Faculty, Saarland University, 66421 Homburg, Germany
| | - Alessandra Moretti
- Department of Medicine I (Cardiology and Angiology), Klinikum rechts der Isar, Technische Universität München, 81675 München, Germany; DZHK (German Centre for Cardiovascular Research), partner site Munich Heart Alliance, Munich, Germany
| | - Karl-Ludwig Laugwitz
- Department of Medicine I (Cardiology and Angiology), Klinikum rechts der Isar, Technische Universität München, 81675 München, Germany; DZHK (German Centre for Cardiovascular Research), partner site Munich Heart Alliance, Munich, Germany
| | - Veit Flockerzi
- Experimental and Clinical Pharmacology and Toxicology, Centre for Molecular Signaling (PZMS), Medical Faculty, Saarland University, 66421 Homburg, Germany
| | - Sandra Ruppenthal
- Molecular Cell Biology, Centre for Molecular Signaling (PZMS), Medical Faculty, Saarland University, 66421 Homburg, Germany
| | - Peter Lipp
- Molecular Cell Biology, Centre for Molecular Signaling (PZMS), Medical Faculty, Saarland University, 66421 Homburg, Germany.
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32
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A structural overview of the ion channels of the TRPM family. Cell Calcium 2019; 85:102111. [PMID: 31812825 DOI: 10.1016/j.ceca.2019.102111] [Citation(s) in RCA: 110] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Revised: 11/13/2019] [Accepted: 11/14/2019] [Indexed: 12/20/2022]
Abstract
The TRPM (transient receptor potential melastatin) family belongs to the superfamily of TRP cation channels. The TRPM subfamily is composed of eight members that are involved in diverse biological functions such as temperature sensing, inflammation, insulin secretion, and redox sensing. Since the first cloning of TRPM1 in 1998, tremendous progress has been made uncovering the function, structure, and pharmacology of this family. Complete structures of TRPM2, TRPM4, and TRPM8, as well as a partial structure of TRPM7, have been determined by cryo-EM, providing insights into their channel assembly, ion permeation, gating mechanisms, and structural pharmacology. Here we summarize the current knowledge about channel structure, emphasizing general features and principles of the structure of TRPM channels discovered since 2017. We also discuss some of the key unresolved issues in the field, including the molecular mechanisms underlying voltage and temperature dependence, as well as the functions of the TRPM channels' C-terminal domains.
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33
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Noh J, Chung JM. Modulation of Dopaminergic Neuronal Excitability by Zinc through the Regulation of Calcium-related Channels. Exp Neurobiol 2019; 28:578-592. [PMID: 31698550 PMCID: PMC6844832 DOI: 10.5607/en.2019.28.5.578] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2019] [Revised: 10/28/2019] [Accepted: 10/28/2019] [Indexed: 11/19/2022] Open
Abstract
Depending on the intracellular buffering of calcium by chelation, zinc has the following two apparent effects on neuronal excitability: enhancement or reduction. Zinc increased tonic activity in the depolarized state when neurons were intracellularly dialyzed with EGTA but attenuated the neuronal activity when BAPTA was used as an intracellular calcium buffer. This suggests that neuronal excitability can be modulated by zinc, depending on the internal calcium buffering capacity. In this study, we elucidated the mechanisms of zinc-mediated alterations in neuronal excitability and determined the effect of calcium-related channels on zinc-mediated alterations in excitability. The zinc-induced augmentation of firing activity was mediated via the inhibition of small-conductance calcium-activated potassium (SK) channels with not only the contribution of voltage-gated L-type calcium channels (VGCCs) and ryanodine receptors (RyRs), but also through the activation of VGCCs via melastatin-like transient receptor potential channels. We suggest that zinc modulates the dopaminergic neuronal activity by regulating not only SK channels as calcium sensors, but also VGCCs or RyRs as calcium sources. Our results suggest that the cytosolic calcium-buffering capacity can tightly regulate zinc-induced neuronal firing patterns and that local calcium-signaling domains can determine the physiological and pathological state of synaptic activity in the dopaminergic system.
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Affiliation(s)
- Jihyun Noh
- Department of Science Education, Dankook University, Yongin 16890, Korea
| | - Jun-Mo Chung
- Department of Brain and Cognitive Sciences, Ewha Womans University, Seoul 03760, Korea
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34
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Emerging structural biology of TRPM subfamily channels. Cell Calcium 2019; 79:75-79. [DOI: 10.1016/j.ceca.2019.02.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Revised: 02/28/2019] [Accepted: 02/28/2019] [Indexed: 12/20/2022]
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35
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Phillips RS, John TT, Koizumi H, Molkov YI, Smith JC. Biophysical mechanisms in the mammalian respiratory oscillator re-examined with a new data-driven computational model. eLife 2019; 8:41555. [PMID: 30907727 PMCID: PMC6433470 DOI: 10.7554/elife.41555] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Accepted: 02/07/2019] [Indexed: 12/11/2022] Open
Abstract
An autorhythmic population of excitatory neurons in the brainstem pre-Bötzinger complex is a critical component of the mammalian respiratory oscillator. Two intrinsic neuronal biophysical mechanisms—a persistent sodium current (INaP) and a calcium-activated non-selective cationic current (ICAN)—were proposed to individually or in combination generate cellular- and circuit-level oscillations, but their roles are debated without resolution. We re-examined these roles in a model of a synaptically connected population of excitatory neurons with ICAN and INaP. This model robustly reproduces experimental data showing that rhythm generation can be independent of ICAN activation, which determines population activity amplitude. This occurs when ICAN is primarily activated by neuronal calcium fluxes driven by synaptic mechanisms. Rhythm depends critically on INaP in a subpopulation forming the rhythmogenic kernel. The model explains how the rhythm and amplitude of respiratory oscillations involve distinct biophysical mechanisms.
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Affiliation(s)
- Ryan S Phillips
- Cellular and Systems Neurobiology Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, United States.,Department of Physics, University of New Hampshire, Durham, United States
| | - Tibin T John
- Cellular and Systems Neurobiology Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, United States
| | - Hidehiko Koizumi
- Cellular and Systems Neurobiology Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, United States
| | - Yaroslav I Molkov
- Department of Mathematics and Statistics, Georgia State University, Atlanta, United States.,Neuroscience Institute, Georgia State University, Atlanta, United States
| | - Jeffrey C Smith
- Cellular and Systems Neurobiology Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, United States
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36
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Picardo MCD, Sugimura YK, Dorst KE, Kallurkar PS, Akins VT, Ma X, Teruyama R, Guinamard R, Kam K, Saha MS, Del Negro CA. Trpm4 ion channels in pre-Bötzinger complex interneurons are essential for breathing motor pattern but not rhythm. PLoS Biol 2019; 17:e2006094. [PMID: 30789900 PMCID: PMC6400419 DOI: 10.1371/journal.pbio.2006094] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Revised: 03/05/2019] [Accepted: 02/05/2019] [Indexed: 12/21/2022] Open
Abstract
Inspiratory breathing movements depend on pre-Bötzinger complex (preBötC) interneurons that express calcium (Ca2+)-activated nonselective cationic current (ICAN) to generate robust neural bursts. Hypothesized to be rhythmogenic, reducing ICAN is predicted to slow down or stop breathing; its contributions to motor pattern would be reflected in the magnitude of movements (output). We tested the role(s) of ICAN using reverse genetic techniques to diminish its putative ion channels Trpm4 or Trpc3 in preBötC neurons in vivo. Adult mice transduced with Trpm4-targeted short hairpin RNA (shRNA) progressively decreased the tidal volume of breaths yet surprisingly increased breathing frequency, often followed by gasping and fatal respiratory failure. Mice transduced with Trpc3-targeted shRNA survived with no changes in breathing. Patch-clamp and field recordings from the preBötC in mouse slices also showed an increase in the frequency and a decrease in the magnitude of preBötC neural bursts in the presence of Trpm4 antagonist 9-phenanthrol, whereas the Trpc3 antagonist pyrazole-3 (pyr-3) showed inconsistent effects on magnitude and no effect on frequency. These data suggest that Trpm4 mediates ICAN, whose influence on frequency contradicts a direct role in rhythm generation. We conclude that Trpm4-mediated ICAN is indispensable for motor output but not the rhythmogenic core mechanism of the breathing central pattern generator.
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Affiliation(s)
- Maria Cristina D. Picardo
- Department of Applied Science, Integrated Science Center, William & Mary, Williamsburg, Virginia, United States of America
| | - Yae K. Sugimura
- Department of Applied Science, Integrated Science Center, William & Mary, Williamsburg, Virginia, United States of America
| | - Kaitlyn E. Dorst
- Department of Applied Science, Integrated Science Center, William & Mary, Williamsburg, Virginia, United States of America
| | - Prajkta S. Kallurkar
- Department of Applied Science, Integrated Science Center, William & Mary, Williamsburg, Virginia, United States of America
| | - Victoria T. Akins
- Department of Applied Science, Integrated Science Center, William & Mary, Williamsburg, Virginia, United States of America
| | - Xingru Ma
- Department of Applied Science, Integrated Science Center, William & Mary, Williamsburg, Virginia, United States of America
| | - Ryoichi Teruyama
- Biological Sciences, Louisiana State University, Baton Rouge, Louisiana, United States of America
| | - Romain Guinamard
- Signalisation, Electrophysiologie et Imagerie des Lésions d’Ischémie-Reperfusion Myocardique, Normandie Université, UNICAEN, Caen, France
| | - Kaiwen Kam
- Department of Cell Biology and Anatomy, Chicago Medical School, Rosalind Franklin University, Chicago, Illinois, United States of America
| | - Margaret S. Saha
- Department of Biology, Integrated Science Center, William & Mary, Williamsburg, Virginia, United States of America
| | - Christopher A. Del Negro
- Department of Applied Science, Integrated Science Center, William & Mary, Williamsburg, Virginia, United States of America
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37
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Farashi S, Sasanpour P, Rafii-Tabar H. The role of the transient receptor potential melastatin5 (TRPM5) channels in the pancreatic β-cell electrical activity: A computational modeling study. Comput Biol Chem 2018; 76:101-108. [DOI: 10.1016/j.compbiolchem.2018.05.019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2017] [Revised: 03/31/2018] [Accepted: 05/15/2018] [Indexed: 01/27/2023]
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38
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Bishnoi M, Khare P, Brown L, Panchal SK. Transient receptor potential (TRP) channels: a metabolic TR(i)P to obesity prevention and therapy. Obes Rev 2018; 19:1269-1292. [PMID: 29797770 DOI: 10.1111/obr.12703] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/05/2018] [Revised: 03/26/2018] [Accepted: 04/11/2018] [Indexed: 12/13/2022]
Abstract
Cellular transport of ions, especially by ion channels, regulates physiological function. The transient receptor potential (TRP) channels, with 30 identified so far, are cation channels with high calcium permeability. These ion channels are present in metabolically active tissues including adipose tissue, liver, gastrointestinal tract, brain (hypothalamus), pancreas and skeletal muscle, which suggests a potential role in metabolic disorders including obesity. TRP channels have potentially important roles in adipogenesis, obesity development and its prevention and therapy because of their physiological properties including calcium permeability, thermosensation and taste perception, involvement in cell metabolic signalling and hormone release. This wide range of actions means that organ-specific actions are unlikely, thus increasing the possibility of adverse effects. Delineation of responses to TRP channels has been limited by the poor selectivity of available agonists and antagonists. Food constituents that can modulate TRP channels are of interest in controlling metabolic status. TRP vanilloid 1 channels modulated by capsaicin have been the most studied, suggesting that this may be the first target for effective pharmacological modulation in obesity. This review shows that most of the TRP channels are potential targets to reduce metabolic disorders through a range of mechanisms.
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Affiliation(s)
- M Bishnoi
- Department of Food and Nutritional Biotechnology, National Agri-Food Biotechnology Institute, S.A.S. Nagar (Mohali), Punjab, India.,Functional Foods Research Group, Institute for Agriculture and the Environment, University of Southern Queensland, Toowoomba, QLD, Australia
| | - P Khare
- Department of Food and Nutritional Biotechnology, National Agri-Food Biotechnology Institute, S.A.S. Nagar (Mohali), Punjab, India
| | - L Brown
- Functional Foods Research Group, Institute for Agriculture and the Environment, University of Southern Queensland, Toowoomba, QLD, Australia.,School of Health and Wellbeing, University of Southern Queensland, Toowoomba, QLD, Australia
| | - S K Panchal
- Functional Foods Research Group, Institute for Agriculture and the Environment, University of Southern Queensland, Toowoomba, QLD, Australia
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39
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Computational modeling of the effect of temperature variations on human pancreatic β-cell activity. J Therm Biol 2018; 75:69-80. [PMID: 30017054 DOI: 10.1016/j.jtherbio.2018.05.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Revised: 05/23/2018] [Accepted: 05/24/2018] [Indexed: 11/22/2022]
Abstract
The effect of temperature variations on the pancreatic β-cell activity and the role of different model compartments in temperature sensing have been investigated using a computational modeling approach. The results of our study show that temperature variations by several degrees can change the dynamical states of the β-cell system. In addition, temperature variations can alter the characteristic features of the membrane voltage, which correlates with insulin secretion. Simulation results show that the ion channels such as the L-type calcium, the hERG potassium, sodium channels and the glycolysis pathway are the possible sites for sensing temperature variation. Results indicate that for a small temperature change, even though the frequency and amplitude of electrical activity are altered, the area under the membrane potential curve remains almost unchanged, which implies the existence of a thermoregulatory mechanism for preserving the amount of insulin secretion. Furthermore, the computational analysis shows that the β-cell electrical activity exhibits a bursting pattern in physiological temperature (37 °C) while in vitro studies reported almost the spiking activity at lower temperatures. Since hormone-secreting systems work more efficient in bursting mode, we propose that the pancreatic β-cell works better in the physiological temperature compared with the reference temperature (33 °C).
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40
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Ozhathil LC, Delalande C, Bianchi B, Nemeth G, Kappel S, Thomet U, Ross‐Kaschitza D, Simonin C, Rubin M, Gertsch J, Lochner M, Peinelt C, Reymond J, Abriel H. Identification of potent and selective small molecule inhibitors of the cation channel TRPM4. Br J Pharmacol 2018; 175:2504-2519. [PMID: 29579323 PMCID: PMC6002741 DOI: 10.1111/bph.14220] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Revised: 03/08/2018] [Accepted: 03/16/2018] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND AND PURPOSE TRPM4 is a calcium-activated non-selective cation channel expressed in many tissues and implicated in several diseases, and has not yet been validated as a therapeutic target due to the lack of potent and selective inhibitors. We sought to discover a novel series of small-molecule inhibitors by combining in silico methods and cell-based screening assay, with sub-micromolar potency and improved selectivity from previously reported TRPM4 inhibitors. EXPERIMENTAL APPROACH Here, we developed a high throughput screening compatible assay to record TRPM4-mediated Na+ influx in cells using a Na+ -sensitive dye and used this assay to screen a small set of compounds selected by ligand-based virtual screening using previously known weakly active and non-selective TRPM4 inhibitors as seed molecules. Conventional electrophysiological methods were used to validate the potency and selectivity of the hit compounds in HEK293 cells overexpressing TRPM4 and in endogenously expressing prostate cancer cell line LNCaP. Chemical chaperone property of compound 5 was studied using Western blots and electrophysiology experiments. KEY RESULTS A series of halogenated anthranilic amides were identified with TRPM4 inhibitory properties with sub-micromolar potency and adequate selectivity. We also showed for the first time that a naturally occurring variant of TRPM4, which displays loss-of-expression and function, is rescued by the most promising compound 5 identified in this study. CONCLUSIONS AND IMPLICATIONS The discovery of compound 5, a potent and selective inhibitor of TRPM4 with an additional chemical chaperone feature, revealed new opportunities for studying the role of TRPM4 in human diseases and developing clinical drug candidates.
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Affiliation(s)
- Lijo Cherian Ozhathil
- Institute of Biochemistry and Molecular Medicine, National Center of Competence in Research NCCR TransCureUniversity of BernBernSwitzerland
| | - Clémence Delalande
- Department of Chemistry and Biochemistry, National Center of Competence in Research NCCR TransCureUniversity of BernBernSwitzerland
| | - Beatrice Bianchi
- Institute of Biochemistry and Molecular Medicine, National Center of Competence in Research NCCR TransCureUniversity of BernBernSwitzerland
| | - Gabor Nemeth
- Department of Chemistry and Biochemistry, National Center of Competence in Research NCCR TransCureUniversity of BernBernSwitzerland
| | - Sven Kappel
- Institute of Biochemistry and Molecular Medicine, National Center of Competence in Research NCCR TransCureUniversity of BernBernSwitzerland
| | - Urs Thomet
- Institute of Biochemistry and Molecular Medicine, National Center of Competence in Research NCCR TransCureUniversity of BernBernSwitzerland
| | - Daniela Ross‐Kaschitza
- Institute of Biochemistry and Molecular Medicine, National Center of Competence in Research NCCR TransCureUniversity of BernBernSwitzerland
| | - Céline Simonin
- Department of Chemistry and Biochemistry, National Center of Competence in Research NCCR TransCureUniversity of BernBernSwitzerland
| | - Matthias Rubin
- Institute of Biochemistry and Molecular Medicine, National Center of Competence in Research NCCR TransCureUniversity of BernBernSwitzerland
| | - Jürg Gertsch
- Institute of Biochemistry and Molecular Medicine, National Center of Competence in Research NCCR TransCureUniversity of BernBernSwitzerland
| | - Martin Lochner
- Institute of Biochemistry and Molecular Medicine, National Center of Competence in Research NCCR TransCureUniversity of BernBernSwitzerland
- Department of Chemistry and Biochemistry, National Center of Competence in Research NCCR TransCureUniversity of BernBernSwitzerland
| | - Christine Peinelt
- Institute of Biochemistry and Molecular Medicine, National Center of Competence in Research NCCR TransCureUniversity of BernBernSwitzerland
| | - Jean‐Louis Reymond
- Department of Chemistry and Biochemistry, National Center of Competence in Research NCCR TransCureUniversity of BernBernSwitzerland
| | - Hugues Abriel
- Institute of Biochemistry and Molecular Medicine, National Center of Competence in Research NCCR TransCureUniversity of BernBernSwitzerland
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41
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Tan CH, McNaughton PA. TRPM2 and warmth sensation. Pflugers Arch 2018; 470:787-798. [PMID: 29552700 PMCID: PMC5942353 DOI: 10.1007/s00424-018-2139-7] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Revised: 03/08/2018] [Accepted: 03/09/2018] [Indexed: 01/08/2023]
Abstract
The abilities to detect warmth and heat are critical for the survival of all animals, both in order to be able to identify suitable thermal environments for the many different activities essential for life and to avoid damage caused by extremes of temperature. Several ion channels belonging to the TRP family are activated by non-noxious warmth or by heat and are therefore plausible candidates for thermal detectors, but identifying those that actually regulate warmth and heat detection in intact animals has proven problematic. TRPM2 has recently emerged as a likely candidate for the detector of non-noxious warmth, as it is expressed in sensory neurons, and mice show deficits in the detection of warmth when TRPM2 is genetically deleted. TRPM2 is a chanzyme, containing a thermally activated TRP ion channel domain attached to a C-terminal motif, derived from a mitochondrial ADP ribose pyrophosphatase, that confers on the channel sensitivity to ADP ribose and reactive oxygen species such as hydrogen peroxide. Several open questions remain. Male mammals prefer cooler environments than female, but the molecular basis of this sex difference is unknown. TRPM2 plays a role in regulating body temperature, but are other warmth-detecting mechanisms also involved? TRPM2 is expressed in autonomic neurons, but does it confer a sensory function in addition to the well-known motor functions of autonomic neurons? TRPM2 is thought to play important roles in the immune system, in pain and in insulin secretion, but the mechanisms are unclear. TRPM2 has to date received less attention than many other members of the TRP family but is rapidly assuming importance both in normal physiology and as a key target in disease pathology.
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Affiliation(s)
- Chun-Hsiang Tan
- Department of Neurology, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan
- Graduate Institute of Clinical Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Peter A McNaughton
- Wolfson Centre for Age-Related Diseases, Institute of Psychiatry, Psychology and Neuroscience, Guy's Campus, King's College London, London, SE1 1UL, UK.
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42
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Luo X, Li M, Zhan K, Yang W, Zhang L, Wang K, Yu P, Zhang L. Selective inhibition of TRPM2 channel by two novel synthesized ADPR analogues. Chem Biol Drug Des 2018; 91:552-566. [PMID: 29034580 PMCID: PMC5813235 DOI: 10.1111/cbdd.13119] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2017] [Revised: 07/04/2017] [Accepted: 08/21/2017] [Indexed: 01/02/2023]
Abstract
Transient receptor potential melastatin-2 (TRPM2) channel critical for monitoring internal body temperature is implicated in the pathological processes such as neurodegeneration. However, lacking selective and potent TRPM2 inhibitors impedes investigation and validation of the channel as a drug target. To discover novel and selective TRPM2 inhibitors, a series of adenosine 5'-diphosphoribose analogues were synthesized, and their activities and selectivity were evaluated. Whole-cell patch-clamp recordings were employed for screen and evaluation of synthesized compounds. Two compounds, 7i and 8a, were identified as TRPM2 inhibitors with IC50 of 5.7 and 5.4 μm, respectively. Both 7i and 8a inhibited TRPM2 current without affecting TRPM7, TRPM8, TRPV1 and TRPV3. These two TRPM2 inhibitors can serve as new pharmacological tools for further investigation and validation of TRPM2 channel as a drug target, and the summarized structure-activity relationship (SAR) may also provide insights into further improving existing inhibitors as potential lead compounds.
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Affiliation(s)
- Xiao Luo
- State Key Laboratory of Natural and Biomimetic DrugsPeking UniversityBeijingChina
| | - Meng Li
- Department of NeurobiologyNeuroscience Research InstitutePeking University Health Science CenterPeking University School of Pharmaceutical SciencesBeijingChina
| | - Kaiyu Zhan
- Department of NeurobiologyZhejiang University School of MedicineHangzhouZhejiangChina
| | - Wei Yang
- Department of NeurobiologyZhejiang University School of MedicineHangzhouZhejiangChina
| | - Lihe Zhang
- State Key Laboratory of Natural and Biomimetic DrugsPeking UniversityBeijingChina
| | - KeWei Wang
- Department of NeurobiologyNeuroscience Research InstitutePeking University Health Science CenterPeking University School of Pharmaceutical SciencesBeijingChina
- Department of PharmacologySchool of PharmacyQingdao UniversityQingdaoChina
| | - Peilin Yu
- Department of ToxicologySchool of Public HealthZhejiang UniversityHangzhouZhejiangChina
| | - Liangren Zhang
- State Key Laboratory of Natural and Biomimetic DrugsPeking UniversityBeijingChina
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43
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Vennekens R, Mesuere M, Philippaert K. TRPM5 in the battle against diabetes and obesity. Acta Physiol (Oxf) 2018; 222. [PMID: 28834354 DOI: 10.1111/apha.12949] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2017] [Revised: 06/06/2017] [Accepted: 08/09/2017] [Indexed: 12/22/2022]
Abstract
TRPM5 is a non-selective monovalent cation channel activated by increases in intracellular Ca2+ . It has a distinct expression pattern: expression is detected in chemosensitive tissues from solitary chemosensory cells to the taste receptor cells and in pancreatic β-cells. The role of TRPM5 has been investigated with the use of knockout mouse models. Trpm5-/- mice have a lack of type II taste perception and show reduced glucose-induced insulin secretion. Expression levels of TRPM5 are reduced in obese, leptin-signalling-deficient mice, and mutations in TRPM5 have been associated with type II diabetes and metabolic syndrome. In this review, we aim to give an overview of the activation, selectivity, modulation and physiological roles of TRPM5.
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Affiliation(s)
- R. Vennekens
- VIB Center for Brain & Disease Research; Leuven Belgium
- Laboratory of Ion Channel Research; TRP Research Platform Leuven (TRPLe), Department of Cellular and Molecular Medicine; KU Leuven, Leuven Belgium
| | - M. Mesuere
- VIB Center for Brain & Disease Research; Leuven Belgium
- Laboratory of Ion Channel Research; TRP Research Platform Leuven (TRPLe), Department of Cellular and Molecular Medicine; KU Leuven, Leuven Belgium
| | - K. Philippaert
- VIB Center for Brain & Disease Research; Leuven Belgium
- Laboratory of Ion Channel Research; TRP Research Platform Leuven (TRPLe), Department of Cellular and Molecular Medicine; KU Leuven, Leuven Belgium
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44
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Dutta Banik D, Martin LE, Freichel M, Torregrossa AM, Medler KF. TRPM4 and TRPM5 are both required for normal signaling in taste receptor cells. Proc Natl Acad Sci U S A 2018; 115:E772-E781. [PMID: 29311301 PMCID: PMC5789955 DOI: 10.1073/pnas.1718802115] [Citation(s) in RCA: 83] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Peripheral taste receptor cells use multiple signaling pathways to transduce taste stimuli into output signals that are sent to the brain. Transient receptor potential melastatin 5 (TRPM5), a sodium-selective TRP channel, functions as a common downstream component in sweet, bitter, and umami signaling pathways. In the absence of TRPM5, mice have a reduced, but not abolished, ability to detect stimuli, suggesting that a TRPM5-independent pathway also contributes to these signals. Here, we identify a critical role for the sodium-selective TRP channel TRPM4 in taste transduction. Using live cell imaging and behavioral studies in KO mice, we show that TRPM4 and TRPM5 are both involved in taste-evoked signaling. Loss of either channel significantly impairs taste, and loss of both channels completely abolishes the ability to detect bitter, sweet, or umami stimuli. Thus, both TRPM4 and TRPM5 are required for transduction of taste stimuli.
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Affiliation(s)
| | - Laura E Martin
- Department of Psychology, University at Buffalo, Buffalo, NY 14260
| | - Marc Freichel
- Pharmakologisches Institut, Universität Heidelberg, D-69120 Heidelberg, Germany
| | | | - Kathryn F Medler
- Department of Biological Sciences, University at Buffalo, Buffalo, NY 14260;
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45
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Philippaert K, Kerselaers S, Voets T, Vennekens R. A Thallium-Based Screening Procedure to Identify Molecules That Modulate the Activity of Ca2+-Activated Monovalent Cation-Selective Channels. SLAS DISCOVERY 2018; 23:341-352. [DOI: 10.1177/2472555217748932] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
TRPM5 functions as a calcium-activated monovalent cation-selective ion channel and is expressed in a variety of cell types. Dysfunction of this type of channel has been recently implied in cardiac arrhythmias, diabetes, and other pathologies. Therefore, a growing interest has emerged to develop the pharmacology of these ion channels. We optimized a screening assay based on the thallium flux through the TRPM5 channel and a fluorescent thallium dye as a probe for channel activity. We show that this assay is capable of identifying molecules that inhibit or potentiate calcium-activated monovalent cation-selective ion channels.
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Affiliation(s)
- Koenraad Philippaert
- Laboratory of Ion Channel Research, Department of Cellular and Molecular Medicine, KULeuven, Leuven, Vlaams Brabant, Belgium
- TRP Research Platform Leuven (TRPLe), KULeuven, Leuven, Belgium
- VIB Center for Brain & Disease Research, Leuven, Belgium
| | - Sara Kerselaers
- Laboratory of Ion Channel Research, Department of Cellular and Molecular Medicine, KULeuven, Leuven, Vlaams Brabant, Belgium
- TRP Research Platform Leuven (TRPLe), KULeuven, Leuven, Belgium
- VIB Center for Brain & Disease Research, Leuven, Belgium
| | - Thomas Voets
- Laboratory of Ion Channel Research, Department of Cellular and Molecular Medicine, KULeuven, Leuven, Vlaams Brabant, Belgium
- TRP Research Platform Leuven (TRPLe), KULeuven, Leuven, Belgium
- VIB Center for Brain & Disease Research, Leuven, Belgium
| | - Rudi Vennekens
- Laboratory of Ion Channel Research, Department of Cellular and Molecular Medicine, KULeuven, Leuven, Vlaams Brabant, Belgium
- TRP Research Platform Leuven (TRPLe), KULeuven, Leuven, Belgium
- VIB Center for Brain & Disease Research, Leuven, Belgium
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Guo J, She J, Zeng W, Chen Q, Bai XC, Jiang Y. Structures of the calcium-activated, non-selective cation channel TRPM4. Nature 2017; 552:205-209. [PMID: 29211714 PMCID: PMC5901961 DOI: 10.1038/nature24997] [Citation(s) in RCA: 135] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2017] [Accepted: 11/03/2017] [Indexed: 12/12/2022]
Abstract
TRPM4 is a calcium-activated, phosphatidylinositol-4,5-bisphosphate (PtdIns(4,5)P2) -modulated, non-selective cation channel that belongs to the family of melastatin-related transient receptor potential (TRPM) channels. Here we present the electron cryo-microscopy structures of the mouse TRPM4 channel with and without ATP. TRPM4 consists of multiple transmembrane and cytosolic domains, which assemble into a three-tiered architecture. The N-terminal nucleotide-binding domain and the C-terminal coiled-coil participate in the tetrameric assembly of the channel; ATP binds at the nucleotide-binding domain and inhibits channel activity. TRPM4 has an exceptionally wide filter but is only permeable to monovalent cations; filter residue Gln973 is essential in defining monovalent selectivity. The S1-S4 domain and the post-S6 TRP domain form the central gating apparatus that probably houses the Ca2+- and PtdIns(4,5)P2-binding sites. These structures provide an essential starting point for elucidating the complex gating mechanisms of TRPM4 and reveal the molecular architecture of the TRPM family.
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Affiliation(s)
- Jiangtao Guo
- Department of Physiology, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9040, USA.,Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, Texas 75390-8816, USA
| | - Ji She
- Department of Physiology, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9040, USA.,Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, Texas 75390-8816, USA
| | - Weizhong Zeng
- Department of Physiology, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9040, USA.,Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, Texas 75390-8816, USA.,Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9040, USA
| | - Qingfeng Chen
- Department of Physiology, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9040, USA.,Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, Texas 75390-8816, USA.,Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9040, USA
| | - Xiao-Chen Bai
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, Texas 75390-8816, USA.,Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9039, USA
| | - Youxing Jiang
- Department of Physiology, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9040, USA.,Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, Texas 75390-8816, USA.,Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9040, USA
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47
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Electron cryo-microscopy structure of a human TRPM4 channel. Nature 2017; 552:200-204. [DOI: 10.1038/nature24674] [Citation(s) in RCA: 112] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Accepted: 10/23/2017] [Indexed: 12/18/2022]
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48
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Keckeis S, Wernecke L, Salchow DJ, Reichhart N, Strauß O. Activation of a Ca 2+-dependent cation conductance with properties of TRPM2 by reactive oxygen species in lens epithelial cells. Exp Eye Res 2017; 161:61-70. [PMID: 28603015 DOI: 10.1016/j.exer.2017.06.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Revised: 05/23/2017] [Accepted: 06/01/2017] [Indexed: 02/03/2023]
Abstract
Ion channels are crucial for maintenance of ion homeostasis and transparency of the lens. The lens epithelium is the metabolically and electrophysiologically active cell type providing nutrients, ions and water to the lens fiber cells. Ca2+-dependent non-selective ion channels seem to play an important role for ion homeostasis. The aim of the study was to identify and characterize Ca2+- and reactive oxygen species (ROS)-dependent non-selective cation channels in human lens epithelial cells. RT-PCR revealed gene expression of the Ca2+-activated non-selective cation channels TRPC3, TRPM2, TRPM4 and Ano6 in both primary lens epithelial cells and the cell line HLE-B3, whereas TRPM5 mRNA was only found in HLE-B3 cells. Using whole-cell patch-clamp technique, ionomycin evoked non-selective cation currents with linear current-voltage relationship in both cell types. The current was decreased by flufenamic acid (FFA), 2-APB, 9-phenanthrol and miconazole, but insensitive to DIDS, ruthenium red, and intracellularly applied spermine. H2O2 evoked a comparable current, abolished by FFA. TRPM2 protein expression in HLE-B3 cells was confirmed by means of immunocytochemistry and western blot. In summary, we conclude that lens epithelial cells functionally express Ca2+- and H2O2-activated non-selective cation channels with properties of TRPM2.
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Affiliation(s)
- Susanne Keckeis
- Experimental Ophthalmology, Department of Ophthalmology, Charité University Medicine Berlin, Berlin, Germany
| | - Laura Wernecke
- Experimental Ophthalmology, Department of Ophthalmology, Charité University Medicine Berlin, Berlin, Germany
| | - Daniel J Salchow
- Department of Ophthalmology, Charité University Medicine Berlin, Berlin, Germany
| | - Nadine Reichhart
- Experimental Ophthalmology, Department of Ophthalmology, Charité University Medicine Berlin, Berlin, Germany.
| | - Olaf Strauß
- Experimental Ophthalmology, Department of Ophthalmology, Charité University Medicine Berlin, Berlin, Germany.
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49
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Lin EC, Combe CL, Gasparini S. Differential Contribution of Ca 2+-Dependent Mechanisms to Hyperexcitability in Layer V Neurons of the Medial Entorhinal Cortex. Front Cell Neurosci 2017; 11:182. [PMID: 28713246 PMCID: PMC5491848 DOI: 10.3389/fncel.2017.00182] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Accepted: 06/13/2017] [Indexed: 11/13/2022] Open
Abstract
Temporal lobe epilepsy is characterized by recurrent seizures in one or both temporal lobes of the brain; some in vitro models show that epileptiform discharges initiate in entorhinal layer V neurons and then spread into other areas of the temporal lobe. We previously found that, in the presence of GABAA receptor antagonists, stimulation of afferent fibers, terminating both at proximal and distal dendritic locations, initiated hyperexcitable bursts in layer V medial entorhinal neurons. We investigated the differential contribution of Ca2+-dependent mechanisms to the plateaus underlying these bursts at proximal and distal synapses. We found that the NMDA glutamatergic antagonist D,L-2-amino-5-phosphonovaleric acid (APV; 50 μM) reduced both the area and duration of the bursts at both proximal and distal synapses by about half. The L-type Ca2+ channel blocker nimodipine (10 μM) and the R- and T-type Ca2+ channel blocker NiCl2 (200 μM) decreased the area of the bursts to a lesser extent; none of these effects appeared to be location-dependent. Remarkably, the perfusion of flufenamic acid (FFA; 100 μM), to block Ca2+-activated non-selective cation currents (ICAN) mediated by transient receptor potential (TRP) channels, had a location-dependent effect, by abolishing burst firing and switching the suprathreshold response to a single action potential (AP) for proximal stimulation, but only minimally affecting the bursts evoked by distal stimulation. A similar outcome was found when FFA was pressure-applied locally around the proximal dendrite of the recorded neurons and in the presence of a selective blocker of melastatin TRP (TRPM) channels, 9-phenanthrol (100 μM), whereas a selective blocker of canonical TRP (TRPC) channels, SKF 96365, did not affect the bursts. These results indicate that different mechanisms might contribute to the initiation of hyperexcitability in layer V neurons at proximal and distal synapses and could shed light on the initiation of epileptiform activity in the entorhinal cortex.
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Affiliation(s)
- Eric C Lin
- Neuroscience Center of Excellence, Louisiana State University Health Sciences CenterNew Orleans, LA, United States
| | - Crescent L Combe
- Neuroscience Center of Excellence, Louisiana State University Health Sciences CenterNew Orleans, LA, United States
| | - Sonia Gasparini
- Neuroscience Center of Excellence, Louisiana State University Health Sciences CenterNew Orleans, LA, United States.,Department of Cell Biology and Anatomy, Louisiana State University Health Sciences CenterNew Orleans, LA, United States
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50
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Angstadt JD, Giordano JR, Goncalves AJ. 9-Phenanthrol modulates postinhibitory rebound and afterhyperpolarizing potentials in an excitatory motor neuron of the medicinal leech. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2017; 203:613-633. [DOI: 10.1007/s00359-017-1178-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Revised: 05/01/2017] [Accepted: 05/02/2017] [Indexed: 12/19/2022]
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