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Cen J, Hu N, Shen J, Gao Y, Lu H. Pathological Functions of Lysosomal Ion Channels in the Central Nervous System. Int J Mol Sci 2024; 25:6565. [PMID: 38928271 PMCID: PMC11203704 DOI: 10.3390/ijms25126565] [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: 04/03/2024] [Revised: 06/06/2024] [Accepted: 06/10/2024] [Indexed: 06/28/2024] Open
Abstract
Lysosomes are highly dynamic organelles that maintain cellular homeostasis and regulate fundamental cellular processes by integrating multiple metabolic pathways. Lysosomal ion channels such as TRPML1-3, TPC1/2, ClC6/7, CLN7, and TMEM175 mediate the flux of Ca2+, Cl-, Na+, H+, and K+ across lysosomal membranes in response to osmotic stimulus, nutrient-dependent signals, and cellular stresses. These ion channels serve as the crucial transducers of cell signals and are essential for the regulation of lysosomal biogenesis, motility, membrane contact site formation, and lysosomal homeostasis. In terms of pathophysiology, genetic variations in these channel genes have been associated with the development of lysosomal storage diseases, neurodegenerative diseases, inflammation, and cancer. This review aims to discuss the current understanding of the role of these ion channels in the central nervous system and to assess their potential as drug targets.
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Affiliation(s)
| | | | | | - Yongjing Gao
- Institute of Pain Medicine and Special Environmental Medicine, Co-Innovation Center of Neuroregeneration, Nantong University, Nantong 226019, China; (J.C.); (N.H.); (J.S.)
| | - Huanjun Lu
- Institute of Pain Medicine and Special Environmental Medicine, Co-Innovation Center of Neuroregeneration, Nantong University, Nantong 226019, China; (J.C.); (N.H.); (J.S.)
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2
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Ouologuem L, Bartel K. Endolysosomal transient receptor potential mucolipins and two-pore channels: implications for cancer immunity. Front Immunol 2024; 15:1389194. [PMID: 38840905 PMCID: PMC11150529 DOI: 10.3389/fimmu.2024.1389194] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2024] [Accepted: 05/09/2024] [Indexed: 06/07/2024] Open
Abstract
Past research has identified that cancer cells sustain several cancer hallmarks by impairing function of the endolysosomal system (ES). Thus, maintaining the functional integrity of endolysosomes is crucial, which heavily relies on two key protein families: soluble hydrolases and endolysosomal membrane proteins. Particularly members of the TPC (two-pore channel) and TRPML (transient receptor potential mucolipins) families have emerged as essential regulators of ES function as a potential target in cancer therapy. Targeting TPCs and TRPMLs has demonstrated significant impact on multiple cancer hallmarks, including proliferation, growth, migration, and angiogenesis both in vitro and in vivo. Notably, endosomes and lysosomes also actively participate in various immune regulatory mechanisms, such as phagocytosis, antigen presentation, and the release of proinflammatory mediators. Yet, knowledge about the role of TPCs and TRPMLs in immunity is scarce. This prompts a discussion regarding the potential role of endolysosomal ion channels in aiding cancers to evade immune surveillance and destruction. Specifically, understanding the interplay between endolysosomal ion channels and cancer immunity becomes crucial. Our review aims to comprehensively explore the current knowledge surrounding the roles of TPCs and TRPMLs in immunity, whilst emphasizing the critical need to elucidate their specific contributions to cancer immunity by pointing out current research gaps that should be addressed.
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Affiliation(s)
| | - Karin Bartel
- Department of Pharmacy, Drug Delivery, Ludwig-Maximilians-University Munich, Munich, Germany
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3
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Wang Y, Wang J, Yan Z, Liu S, Xu W. Microenvironment modulation by key regulators of RNA N6-methyladenosine modification in respiratory allergic diseases. BMC Pulm Med 2023; 23:210. [PMID: 37328853 DOI: 10.1186/s12890-023-02499-0] [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: 11/15/2022] [Accepted: 05/30/2023] [Indexed: 06/18/2023] Open
Abstract
BACKGROUND RNA N6-methyladenosine (m6A) regulators are considered post-transcriptional regulators that affect several biological functions, and their role in immunity, in particular, is emerging. However, the role of m6A regulators in respiratory allergic diseases remains unclear. Therefore, we aimed to investigate the role of key m6A regulators in mediating respiratory allergic diseases and immune microenvironment infiltration characteristics. METHODS We downloaded gene expression profiles of respiratory allergies from the Gene Expression Omnibus (GEO) database and we performed hierarchical clustering, difference analysis, and construction of predictive models to identify hub m6A regulators that affect respiratory allergies. Next, we investigate the underlying biological mechanisms of key m6A regulators by performing PPI network analysis, functional enrichment analysis, and immune microenvironment infiltration analysis. In addition, we performed a drug sensitivity analysis on the key m6A regulator, hoping to be able to provide some implications for clinical medication. RESULTS In this study, we identified four hub m6A regulators that affect the respiratory allergy and investigated the underlying biological mechanisms. In addition, studies on the characteristics of immune microenvironment infiltration revealed that the expression of METTL14, METTL16, and RBM15B correlated with the infiltration of the mast and Th2 cells in respiratory allergy, and METTL16 expression was found to be significantly negatively correlated with macrophages for the first time (R = -0.53, P < 0.01). Finally, a key m6A regulator, METTL14, was screened by combining multiple algorithms. In addition, by performing a drug sensitivity analysis on METTL14, we hypothesized that it may play an important role in the improvement of allergic symptoms in the upper and lower airways with topical nasal glucocorticoids. CONCLUSIONS Our findings suggest that m6A regulators, particularly METTL14, play a crucial role in the development of respiratory allergic diseases and the infiltration of immune cells. These results may provide insight into the mechanism of action of methylprednisolone in treating respiratory allergic diseases.
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Affiliation(s)
- Yuting Wang
- Department of Otorhinolaryngology, Dongfang Hospital Affiliated to Beijing University of Chinese Medicine, Beijing, China
| | - Jiaxi Wang
- Department of Otorhinolaryngology, Dongfang Hospital Affiliated to Beijing University of Chinese Medicine, Beijing, China.
| | - Zhanfeng Yan
- Department of Otorhinolaryngology, Dongzhimen Hospital Affiliated to Beijing University of Chinese Medicine, Beijing, China
| | - Siming Liu
- Department of Otorhinolaryngology, Dongzhimen Hospital Affiliated to Beijing University of Chinese Medicine, Beijing, China
| | - Wenlong Xu
- Department of Otorhinolaryngology, Dongzhimen Hospital Affiliated to Beijing University of Chinese Medicine, Beijing, China
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4
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Steiner P, Arlt E, Boekhoff I, Gudermann T, Zierler S. TPC Functions in the Immune System. Handb Exp Pharmacol 2023; 278:71-92. [PMID: 36639434 DOI: 10.1007/164_2022_634] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/28/2023]
Abstract
Two-pore channels (TPCs) are novel intracellular cation channels, which play a key role in numerous (patho-)physiological and immunological processes. In this chapter, we focus on their function in immune cells and immune reactions. Therefore, we first give an overview of the cellular immune response and the partaking immune cells. Second, we concentrate on ion channels which in the past have been shown to play an important role in the regulation of immune cells. The main focus is then directed to TPCs, which are primarily located in the membranes of acidic organelles, such as lysosomes or endolysosomes but also certain other vesicles. They regulate Ca2+ homeostasis and thus Ca2+ signaling in immune cells. Due to this important functional role, TPCs are enjoying increasing attention within the field of immunology in the last few decades but are also becoming more pertinent as pharmacological targets for the treatment of pro-inflammatory diseases such as allergic hypersensitivity. However, to uncover the precise molecular mechanism of TPCs in immune cell responses, further molecular, genetic, and ultrastructural investigations on TPCs are necessary, which then may pave the way to develop novel therapeutic strategies to treat diseases such as anaphylaxis more specifically.
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Affiliation(s)
- Philip Steiner
- Institute of Pharmacology, Faculty of Medicine, Johannes Kepler University Linz, Linz, Austria
| | - Elisabeth Arlt
- Walther Straub Institute of Pharmacology and Toxicology, Faculty of Medicine, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Ingrid Boekhoff
- Walther Straub Institute of Pharmacology and Toxicology, Faculty of Medicine, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Thomas Gudermann
- Walther Straub Institute of Pharmacology and Toxicology, Faculty of Medicine, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Susanna Zierler
- Institute of Pharmacology, Faculty of Medicine, Johannes Kepler University Linz, Linz, Austria.
- Walther Straub Institute of Pharmacology and Toxicology, Faculty of Medicine, Ludwig-Maximilians-Universität München, Munich, Germany.
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5
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Rautenberg S, Keller M, Leser C, Chen CC, Bracher F, Grimm C. Expanding the Toolbox: Novel Modulators of Endolysosomal Cation Channels. Handb Exp Pharmacol 2023; 278:249-276. [PMID: 35902436 DOI: 10.1007/164_2022_605] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/28/2023]
Abstract
Functional characterization of endolysosomal ion channels is challenging due to their intracellular location. With recent advances in endolysosomal patch clamp technology, it has become possible to directly measure ion channel currents across endolysosomal membranes. Members of the transient receptor potential (TRP) cation channel family, namely the endolysosomal TRPML channels (TRPML1-3), also called mucolipins, as well as the distantly related two-pore channels (TPCs) have recently been characterized in more detail with endolysosomal patch clamp techniques. However, answers to many physiological questions require work in intact cells or animal models. One major obstacle thereby is that the known endogenous ligands of TRPMLs and TPCs are anionic in nature and thus impermeable for cell membranes. Microinjection, on the other hand, is technically demanding. There is also a risk of losing essential co-factors for channel activation or inhibition in isolated preparations. Therefore, lipophilic, membrane-permeable small-molecule activators and inhibitors for TRPMLs and TPCs are urgently needed. Here, we describe and discuss the currently available small-molecule modulators of TRPMLs and TPCs.
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Affiliation(s)
- Susanne Rautenberg
- Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-University, Munich, Germany
| | - Marco Keller
- Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-University, Munich, Germany
| | - Charlotte Leser
- Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-University, Munich, Germany
| | - Cheng-Chang Chen
- Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-University, Munich, Germany
| | - Franz Bracher
- Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-University, Munich, Germany.
| | - Christian Grimm
- Department of Pharmacology and Toxicology, Medical Faculty, Ludwig-Maximilians-University, Munich, Germany.
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Abstract
The discovery of NAADP-evoked Ca2+ release in sea urchin eggs and then as a ubiquitous Ca2+ mobilizing messenger has introduced several novel paradigms to our understanding of Ca2+ signalling, not least in providing a link between cell stimulation and Ca2+ release from lysosomes and other acidic Ca2+ storage organelles. In addition, the hallmark concentration-response relationship of NAADP-mediated Ca2+ release, shaped by striking activation/desensitization mechanisms, influences its actions as an intracellular messenger. There has been recent progress in our understanding of the molecular mechanisms underlying NAADP-evoked Ca2+ release, such as the identification of the endo-lysosomal two-pore channel family of cation channels (TPCs) as their principal target and the identity of NAADP-binding proteins that complex with them. The NAADP/TPC signalling axis has gained recent prominence in pathophysiology for their roles in such disease processes as neurodegeneration, tumorigenesis and cellular viral entry.
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Affiliation(s)
- Antony Galione
- Department of Pharmacology, University of Oxford, Oxford, UK.
| | - Lianne C Davis
- Department of Pharmacology, University of Oxford, Oxford, UK
| | - Lora L Martucci
- Department of Pharmacology, University of Oxford, Oxford, UK
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7
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Abstract
Mast cells originate from the CD34+/CD117+ hematopoietic progenitors in the bone marrow, migrate into circulation, and ultimately mature and reside in peripheral tissues. Microbiota/metabolites and certain immune cells (e.g., Treg cells) play a key role in maintaining immune tolerance. Cross-linking of allergen-specific IgE on mast cells activates the high-affinity membrane-bound receptor FcεRI, thereby initiating an intracellular signal cascade, leading to degranulation and release of pro-inflammatory mediators. The intracellular signal transduction is intricately regulated by various kinases, transcription factors, and cytokines. Importantly, multiple signal components in the FcεRI-mast cell–mediated allergic cascade can be targeted for therapeutic purposes. Pharmacological interventions that include therapeutic antibodies against IgE, FcεRI, and cytokines as well as inhibitors/activators of several key intracellular signaling molecues have been used to inhibit allergic reactions. Other factors that are not part of the signal pathway but can enhance an individual’s susceptibility to allergen stimulation are referred to as cofactors. Herein, we provide a mechanistic overview of the FcεRI-mast cell–mediated allergic signaling. This will broaden our scope and visions on specific preventive and therapeutic strategies for the clinical management of mast cell–associated hypersensitivity reactions.
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8
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Two-pore channels: going with the flows. Biochem Soc Trans 2022; 50:1143-1155. [PMID: 35959977 PMCID: PMC9444070 DOI: 10.1042/bst20220229] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Revised: 07/21/2022] [Accepted: 07/25/2022] [Indexed: 11/26/2022]
Abstract
In recent years, our understanding of the structure, mechanisms and functions of the endo-lysosomal TPC (two-pore channel) family have grown apace. Gated by the second messengers, NAADP and PI(3,5)P2, TPCs are an integral part of fundamental signal-transduction pathways, but their array and plasticity of cation conductances (Na+, Ca2+, H+) allow them to variously signal electrically, osmotically or chemically. Their relative tissue- and organelle-selective distribution, together with agonist-selective ion permeabilities provides a rich palette from which extracellular stimuli can choose. TPCs are emerging as mediators of immunity, cancer, metabolism, viral infectivity and neurodegeneration as this short review attests.
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Steiner P, Arlt E, Boekhoff I, Gudermann T, Zierler S. Two-Pore Channels Regulate Inter-Organellar Ca 2+ Homeostasis in Immune Cells. Cells 2022; 11:1465. [PMID: 35563771 PMCID: PMC9103377 DOI: 10.3390/cells11091465] [Citation(s) in RCA: 2] [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: 03/10/2022] [Revised: 04/13/2022] [Accepted: 04/16/2022] [Indexed: 02/01/2023] Open
Abstract
Two-pore channels (TPCs) are ligand-gated cation-selective ion channels that are preserved in plant and animal cells. In the latter, TPCs are located in membranes of acidic organelles, such as endosomes, lysosomes, and endolysosomes. Here, we focus on the function of these unique ion channels in mast cells, which are leukocytes that mature from myeloid hematopoietic stem cells. The cytoplasm of these innate immune cells contains a large number of granules that comprise messenger substances, such as histamine and heparin. Mast cells, along with basophil granulocytes, play an essential role in anaphylaxis and allergic reactions by releasing inflammatory mediators. Signaling in mast cells is mainly regulated via the release of Ca2+ from the endoplasmic reticulum as well as from acidic compartments, such as endolysosomes. For the crosstalk of these organelles TPCs seem essential. Allergic reactions and anaphylaxis were previously shown to be associated with the endolysosomal two-pore channel TPC1. The release of histamine, controlled by intracellular Ca2+ signals, was increased upon genetic or pharmacologic TPC1 inhibition. Conversely, stimulation of TPC channel activity by one of its endogenous ligands, namely nicotinic adenine dinucleotide phosphate (NAADP) or phosphatidylinositol 3,5-bisphosphate (PI(3,5)P2), were found to trigger the release of Ca2+ from the endolysosomes; thereby improving the effect of TPC1 on regulated mast cell degranulation. In this review we discuss the importance of TPC1 for regulating Ca2+ homeostasis in mast cells and the overall potential of TPC1 as a pharmacological target in anti-inflammatory therapy.
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Affiliation(s)
- Philip Steiner
- Institute of Pharmacology, Medical Faculty, Johannes Kepler University Linz, 4020 Linz, Austria;
| | - Elisabeth Arlt
- Walther Straub Institute of Pharmacology and Toxicology, Medical Faculty, Ludwig Maximilians University Munich, 80336 Munich, Germany; (E.A.); (I.B.); (T.G.)
| | - Ingrid Boekhoff
- Walther Straub Institute of Pharmacology and Toxicology, Medical Faculty, Ludwig Maximilians University Munich, 80336 Munich, Germany; (E.A.); (I.B.); (T.G.)
| | - Thomas Gudermann
- Walther Straub Institute of Pharmacology and Toxicology, Medical Faculty, Ludwig Maximilians University Munich, 80336 Munich, Germany; (E.A.); (I.B.); (T.G.)
| | - Susanna Zierler
- Institute of Pharmacology, Medical Faculty, Johannes Kepler University Linz, 4020 Linz, Austria;
- Walther Straub Institute of Pharmacology and Toxicology, Medical Faculty, Ludwig Maximilians University Munich, 80336 Munich, Germany; (E.A.); (I.B.); (T.G.)
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10
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Martucci LL, Cancela JM. Neurophysiological functions and pharmacological tools of acidic and non-acidic Ca2+ stores. Cell Calcium 2022; 104:102582. [DOI: 10.1016/j.ceca.2022.102582] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Revised: 03/07/2022] [Accepted: 03/23/2022] [Indexed: 02/08/2023]
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11
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Spix B, Butz ES, Chen CC, Rosato AS, Tang R, Jeridi A, Kudrina V, Plesch E, Wartenberg P, Arlt E, Briukhovetska D, Ansari M, Günsel GG, Conlon TM, Wyatt A, Wetzel S, Teupser D, Holdt LM, Ectors F, Boekhoff I, Boehm U, García-Añoveros J, Saftig P, Giera M, Kobold S, Schiller HB, Zierler S, Gudermann T, Wahl-Schott C, Bracher F, Yildirim AÖ, Biel M, Grimm C. Lung emphysema and impaired macrophage elastase clearance in mucolipin 3 deficient mice. Nat Commun 2022; 13:318. [PMID: 35031603 PMCID: PMC8760276 DOI: 10.1038/s41467-021-27860-x] [Citation(s) in RCA: 35] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Accepted: 12/16/2021] [Indexed: 02/06/2023] Open
Abstract
Lung emphysema and chronic bronchitis are the two most common causes of chronic obstructive pulmonary disease. Excess macrophage elastase MMP-12, which is predominantly secreted from alveolar macrophages, is known to mediate the development of lung injury and emphysema. Here, we discovered the endolysosomal cation channel mucolipin 3 (TRPML3) as a regulator of MMP-12 reuptake from broncho-alveolar fluid, driving in two independently generated Trpml3-/- mouse models enlarged lung injury, which is further exacerbated after elastase or tobacco smoke treatment. Mechanistically, using a Trpml3IRES-Cre/eR26-τGFP reporter mouse model, transcriptomics, and endolysosomal patch-clamp experiments, we show that in the lung TRPML3 is almost exclusively expressed in alveolar macrophages, where its loss leads to defects in early endosomal trafficking and endocytosis of MMP-12. Our findings suggest that TRPML3 represents a key regulator of MMP-12 clearance by alveolar macrophages and may serve as therapeutic target for emphysema and chronic obstructive pulmonary disease.
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Affiliation(s)
- Barbara Spix
- Walther Straub Institute of Pharmacology and Toxicology, Faculty of Medicine, Ludwig-Maximilians-University, Munich, Germany
| | - Elisabeth S Butz
- Department of Pharmacy, Ludwig-Maximilians-University, Munich, Germany
- Institute for Neurophysiology, Hannover Medical School, Hannover, Germany
| | - Cheng-Chang Chen
- Department of Pharmacy, Ludwig-Maximilians-University, Munich, Germany
- Department of Clinical Laboratory Sciences and Medical Biotechnology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Anna Scotto Rosato
- Walther Straub Institute of Pharmacology and Toxicology, Faculty of Medicine, Ludwig-Maximilians-University, Munich, Germany
| | - Rachel Tang
- Walther Straub Institute of Pharmacology and Toxicology, Faculty of Medicine, Ludwig-Maximilians-University, Munich, Germany
| | - Aicha Jeridi
- Comprehensive Pneumology Center, Institute of Lung Biology and Disease, Helmholtz Zentrum München, Member of the German Center for Lung Research (DZL), Munich, Germany
| | - Veronika Kudrina
- Walther Straub Institute of Pharmacology and Toxicology, Faculty of Medicine, Ludwig-Maximilians-University, Munich, Germany
| | - Eva Plesch
- Department of Pharmacy, Ludwig-Maximilians-University, Munich, Germany
| | - Philipp Wartenberg
- Saarland University, Center for Molecular Signaling (PZMS), Experimental Pharmacology, Homburg, Germany
| | - Elisabeth Arlt
- Walther Straub Institute of Pharmacology and Toxicology, Faculty of Medicine, Ludwig-Maximilians-University, Munich, Germany
| | - Daria Briukhovetska
- Division of Clinical Pharmacology, Department of Medicine IV, University Hospital Munich, Munich, Germany
| | - Meshal Ansari
- Comprehensive Pneumology Center, Institute of Lung Biology and Disease, Helmholtz Zentrum München, Member of the German Center for Lung Research (DZL), Munich, Germany
| | - Gizem Günes Günsel
- Comprehensive Pneumology Center, Institute of Lung Biology and Disease, Helmholtz Zentrum München, Member of the German Center for Lung Research (DZL), Munich, Germany
| | - Thomas M Conlon
- Comprehensive Pneumology Center, Institute of Lung Biology and Disease, Helmholtz Zentrum München, Member of the German Center for Lung Research (DZL), Munich, Germany
| | - Amanda Wyatt
- Saarland University, Center for Molecular Signaling (PZMS), Experimental Pharmacology, Homburg, Germany
| | - Sandra Wetzel
- Institute of Biochemistry, Christian-Albrechts-University Kiel, Kiel, Germany
| | - Daniel Teupser
- Institute of Laboratory Medicine, University Hospital Munich, Munich, Germany
| | - Lesca M Holdt
- Institute of Laboratory Medicine, University Hospital Munich, Munich, Germany
| | - Fabien Ectors
- FARAH Mammalian Transgenics Platform, Liège University, Liège, Belgium
| | - Ingrid Boekhoff
- Walther Straub Institute of Pharmacology and Toxicology, Faculty of Medicine, Ludwig-Maximilians-University, Munich, Germany
| | - Ulrich Boehm
- Saarland University, Center for Molecular Signaling (PZMS), Experimental Pharmacology, Homburg, Germany
| | - Jaime García-Añoveros
- Departments of Anesthesiology, Physiology and Neurology, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA
| | - Paul Saftig
- Institute of Biochemistry, Christian-Albrechts-University Kiel, Kiel, Germany
| | - Martin Giera
- Center for Proteomics and Metabolomics, Leiden University Medical Center, 2333ZA, Leiden, The Netherlands
| | - Sebastian Kobold
- Division of Clinical Pharmacology, Department of Medicine IV, University Hospital Munich, Munich, Germany
- German Center for Translational Cancer Research (DKTK), partner site Munich, Munich, Germany
| | - Herbert B Schiller
- Comprehensive Pneumology Center, Institute of Lung Biology and Disease, Helmholtz Zentrum München, Member of the German Center for Lung Research (DZL), Munich, Germany
| | - Susanna Zierler
- Walther Straub Institute of Pharmacology and Toxicology, Faculty of Medicine, Ludwig-Maximilians-University, Munich, Germany
- Institute of Pharmacology, Johannes-Keppler-University, Linz, Australia
| | - Thomas Gudermann
- Walther Straub Institute of Pharmacology and Toxicology, Faculty of Medicine, Ludwig-Maximilians-University, Munich, Germany
- German Center of Lung Research (DZL), Munich, Germany
| | | | - Franz Bracher
- Department of Pharmacy, Ludwig-Maximilians-University, Munich, Germany
| | - Ali Önder Yildirim
- Comprehensive Pneumology Center, Institute of Lung Biology and Disease, Helmholtz Zentrum München, Member of the German Center for Lung Research (DZL), Munich, Germany.
| | - Martin Biel
- Department of Pharmacy, Ludwig-Maximilians-University, Munich, Germany.
| | - Christian Grimm
- Walther Straub Institute of Pharmacology and Toxicology, Faculty of Medicine, Ludwig-Maximilians-University, Munich, Germany.
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Barbonari S, D'Amore A, Palombi F, De Cesaris P, Parrington J, Riccioli A, Filippini A. RELEVANCE OF LYSOSOMAL Ca2+ SIGNALLING MACHINERY IN CANCER. Cell Calcium 2022; 102:102539. [DOI: 10.1016/j.ceca.2022.102539] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Revised: 01/05/2022] [Accepted: 01/06/2022] [Indexed: 12/23/2022]
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Davis LC, Morgan AJ, Galione A. Acidic Ca 2+ stores and immune-cell function. Cell Calcium 2021; 101:102516. [PMID: 34922066 DOI: 10.1016/j.ceca.2021.102516] [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: 11/04/2021] [Revised: 12/03/2021] [Accepted: 12/04/2021] [Indexed: 12/11/2022]
Abstract
Acidic organelles act as intracellular Ca2+ stores; they actively sequester Ca2+ in their lumina and release it to the cytosol upon activation of endo-lysosomal Ca2+ channels. Recent data suggest important roles of endo-lysosomal Ca2+ channels, the Two-Pore Channels (TPCs) and the TRPML channels (mucolipins), in different aspects of immune-cell function, particularly impacting membrane trafficking, vesicle fusion/fission and secretion. Remarkably, different channels on the same acidic vesicles can couple to different downstream physiology. Endo-lysosomal Ca2+ stores can act under different modalities, be they acting alone (via local Ca2+ nanodomains around TPCs/TRPMLs) or in conjunction with the ER Ca2+ store (to either promote or suppress global ER Ca2+ release). These different modalities impinge upon functions as broad as phagocytosis, cell-killing, anaphylaxis, immune memory, thrombostasis, and chemotaxis.
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Affiliation(s)
- Lianne C Davis
- Department of Pharmacology, University of Oxford, Mansfield Road, Oxford, OX1 3QT, UK.
| | - Anthony J Morgan
- Department of Pharmacology, University of Oxford, Mansfield Road, Oxford, OX1 3QT, UK
| | - Antony Galione
- Department of Pharmacology, University of Oxford, Mansfield Road, Oxford, OX1 3QT, UK.
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Mast cell activation syndrome: is anaphylaxis part of the phenotype? A systematic review. Curr Opin Allergy Clin Immunol 2021; 21:426-434. [PMID: 34292177 DOI: 10.1097/aci.0000000000000768] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE OF REVIEW Mast cell activation syndrome (MCAS) and anaphylaxis are the result of a spontaneous or triggered pathological degranulation of mast cells (MCs) and might have as substrate normal or pathological MCs (increased burden, aberrant MCs or both). RECENT FINDINGS This review summarizes the most recent evidence on immunoglobulin E (IgE)-mediated and non IgE-mediated mechanisms underlying MC activation and degranulation and highlights the importance of standardized diagnostic criteria for MCAS. Application of these criteria implies that in most cases the clinical presentation of MCAS meets the diagnostic criteria for anaphylaxis. SUMMARY Integrating clinical parameters and diagnostic test recognition and underlying clonal MC disease are of utmost importance for a patient-tailored approach. Hereditary alpha-tryptasemia can be encountered in context of anaphylaxis, MCAS and primary MC disorders.
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15
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Xie Z, Xiang C, Li X, Fan C, Chen T, Liu M, Ma Y, Bai F, Tang W, Hu Y. Discovery of Potent Antiallergic Agents Based on an o-Aminopyridinyl Alkynyl Scaffold. J Med Chem 2021; 64:13588-13603. [PMID: 34476950 DOI: 10.1021/acs.jmedchem.1c00976] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Effective therapeutic agents are highly desired for immune-mediated allergic diseases. Herein, we report the design, synthesis, and structure-activity relationship of an o-aminopyridinyl alkyne series as novel orally bioavailable antiallergic agents, which was identified through phenotypic screening. Compound optimization yielded a highly potent compound 36, which effectively suppressed mast cell degranulation in a dose-dependent manner (IC50, 2.54 nM for RBL-2H3 cells; 48.28 nM for peritoneal mast cells (PMCs)) with a good therapeutic index. It also regulated the activation of FcεRI-mediated downstream signaling proteins in IgE/Ag-stimulated RBL-2H3 cells. In addition, 36 exhibited excellent in vivo pharmacokinetic properties and antiallergic efficacy in both passive systemic anaphylaxis (PSA) and house dust mite (HDM)-induced murine models of pulmonary allergic inflammation. Furthermore, preliminary analysis of the kinases profile identified Src-family kinases as potential targets for 36. Compound 36 may serve as a new valuable lead compound for future antiallergic drug discovery.
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Affiliation(s)
- Zhicheng Xie
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, No. 555 Zu-Chong-Zhi Road, Zhangjiang Hi-Tech Park, Shanghai 201203, China
- University of Chinese Academy of Sciences, 19 Yuquan Road, Beijing 100049, China
| | - Caigui Xiang
- Laboratory of Immunopharmacology, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
- University of Chinese Academy of Sciences, 19 Yuquan Road, Beijing 100049, China
| | - Xin Li
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, No. 555 Zu-Chong-Zhi Road, Zhangjiang Hi-Tech Park, Shanghai 201203, China
- University of Chinese Academy of Sciences, 19 Yuquan Road, Beijing 100049, China
| | - Chen Fan
- Laboratory of Immunopharmacology, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Taiwen Chen
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, No. 555 Zu-Chong-Zhi Road, Zhangjiang Hi-Tech Park, Shanghai 201203, China
- University of Chinese Academy of Sciences, 19 Yuquan Road, Beijing 100049, China
| | - Moting Liu
- Laboratory of Immunopharmacology, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Yanjie Ma
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, No. 555 Zu-Chong-Zhi Road, Zhangjiang Hi-Tech Park, Shanghai 201203, China
| | - Fang Bai
- Laboratory of Immunopharmacology, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Wei Tang
- Laboratory of Immunopharmacology, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
- University of Chinese Academy of Sciences, 19 Yuquan Road, Beijing 100049, China
| | - Youhong Hu
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, No. 555 Zu-Chong-Zhi Road, Zhangjiang Hi-Tech Park, Shanghai 201203, China
- University of Chinese Academy of Sciences, 19 Yuquan Road, Beijing 100049, China
- Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Hangzhou 310024, China
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16
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Two-Pore Channels Regulate Expression of Various Receptors and Their Pathway-Related Proteins in Multiple Ways. Cells 2021; 10:cells10071807. [PMID: 34359976 PMCID: PMC8307395 DOI: 10.3390/cells10071807] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Revised: 07/13/2021] [Accepted: 07/14/2021] [Indexed: 11/17/2022] Open
Abstract
Two-pore channels (TPCs) constitute a small family of ion channels within membranes of intracellular acidic compartments, such as endosomes and lysosomes. They were shown to provide transient and locally restricted Ca2+-currents, likely responsible for fusion and/or fission events of endolysosomal membranes and thereby for intracellular vesicle trafficking. Genetic deletion of TPCs not only affects endocytosis, recycling, and degradation of various surface receptors but also uptake and impact of bacterial protein toxins and entry and intracellular processing of some types of viruses. This review points to important examples of these trafficking defects on one part but mainly focuses on the resulting impact of the TPC inactivation on receptor expression and receptor signaling. Thus, a detailed RNA sequencing analysis using TPC1-deficient fibroblasts uncovered a multitude of changes in the expression levels of surface receptors and their pathway-related signaling proteins. We refer to several classes of receptors such as EGF, TGF, and insulin as well as proteins involved in endocytosis.
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17
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Li Y, Schön C, Chen CC, Yang Z, Liegl R, Murenu E, Schworm B, Klugbauer N, Grimm C, Wahl-Schott C, Michalakis S, Biel M. TPC2 promotes choroidal angiogenesis and inflammation in a mouse model of neovascular age-related macular degeneration. Life Sci Alliance 2021; 4:4/8/e202101047. [PMID: 34183443 PMCID: PMC8321671 DOI: 10.26508/lsa.202101047] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 06/14/2021] [Accepted: 06/15/2021] [Indexed: 12/23/2022] Open
Abstract
This study identifies the endolysosomal two-pore channel TPC2 as a potential novel drug target for age-related macular degeneration (AMD). Inhibition of TPC2 reduces two key clinical hallmarks of the AMD, retinal inflammation and formation of leaky choroi. Age-related macular degeneration (AMD) is the most common cause of blindness among the elderly and can be classified either as dry or as neovascular (or wet). Neovascular AMD is characterized by a strong immune response and the inadequate release of cytokines triggering angiogenesis and induction of photoreceptor death. The pathomechanisms of AMD are only partly understood. Here, we identify the endolysosomal two-pore cation channel TPC2 as a key factor of neovascularization and immune activation in the laser-induced choroidal neovascularization (CNV) mouse model of AMD. Block of TPC2 reduced retinal VEGFA and IL-1β levels and diminished neovascularization and immune activation. Mechanistically, TPC2 mediates cationic currents in endolysosomal organelles of immune cells and lack of TPC2 leads to reduced IL-1β levels in areas of choroidal neovascularization due to endolysosomal trapping. Taken together, our study identifies TPC2 as a promising novel therapeutic target for the treatment of AMD.
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Affiliation(s)
- Yanfen Li
- Department of Pharmacy, Ludwig-Maximilians-Universität München, München, Germany
| | - Christian Schön
- Department of Pharmacy, Ludwig-Maximilians-Universität München, München, Germany
| | - Cheng-Chang Chen
- Department of Pharmacy, Ludwig-Maximilians-Universität München, München, Germany.,Department of Clinical Laboratory Sciences and Medical Biotechnology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Zhuo Yang
- Department of Pharmacy, Ludwig-Maximilians-Universität München, München, Germany
| | - Raffael Liegl
- Department of Ophthalmology, University Hospital, LMU Munich, München, Germany
| | - Elisa Murenu
- Department of Pharmacy, Ludwig-Maximilians-Universität München, München, Germany
| | - Benedikt Schworm
- Department of Ophthalmology, University Hospital, LMU Munich, München, Germany
| | - Norbert Klugbauer
- Institute for Experimental and Clinical Pharmacology and Toxicology, Medical Faculty, Albert-Ludwigs-University, Freiburg, Germany
| | - Christian Grimm
- Walther Straub Institute of Pharmacology and Toxicology, Ludwig-Maximilians-Universität München, München, Germany
| | | | - Stylianos Michalakis
- Department of Pharmacy, Ludwig-Maximilians-Universität München, München, Germany .,Department of Ophthalmology, University Hospital, LMU Munich, München, Germany
| | - Martin Biel
- Department of Pharmacy, Ludwig-Maximilians-Universität München, München, Germany
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18
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Alharbi AF, Parrington J. Deciphering the Role of Endolysosomal Ca 2+ Channels in Immunity. Front Immunol 2021; 12:656965. [PMID: 33986747 PMCID: PMC8111081 DOI: 10.3389/fimmu.2021.656965] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Accepted: 04/09/2021] [Indexed: 12/26/2022] Open
Abstract
The role of endolysosomal Ca2+ signalling in immunity has been a subject of increasing interest in recent years. Here, we discuss evolving knowledge relating to the contribution of endolysosomal Ca2+ channels that include TPCs, TRPMLs, and P2X4R in physiological processes related to innate and adaptive immunity-including phagocytosis, inflammation, cytokine/chemokine release, dendritic, natural killer, and T cell activation and migration-and we underscore the paucity of clinical studies in this field. Emerging biomedical and translational data have led to important new insights into the critical roles of these channels in immune cell function and the regulation of innate and adaptive immune responses. The evolving immunological significance of endolysosomal Ca2+ signalling warrants further investigations to better characterize the roles of these channels in immunity in order to expand our knowledge about the pathology of inflammatory and autoimmune diseases and develop endolysosomal Ca2+ channels as viable biomarkers and therapeutic and preventive targets for remodelling the immune response.
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Affiliation(s)
- Abeer F. Alharbi
- Department of Pharmacology, University of Oxford, Oxford, United Kingdom
- Pharmaceutical Sciences Department, College of Pharmacy, King Saud Bin Abdul-Aziz University for Health Sciences, Riyadh, Saudi Arabia
| | - John Parrington
- Department of Pharmacology, University of Oxford, Oxford, United Kingdom
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19
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Morgan AJ, Davis LC, Galione A. Choreographing endo-lysosomal Ca 2+ throughout the life of a phagosome. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2021; 1868:119040. [PMID: 33872669 DOI: 10.1016/j.bbamcr.2021.119040] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Revised: 04/05/2021] [Accepted: 04/07/2021] [Indexed: 12/20/2022]
Abstract
The emergence of endo-lysosomes as ubiquitous Ca2+ stores with their unique cohort of channels has resulted in their being implicated in a growing number of processes in an ever-increasing number of cell types. The architectural and regulatory constraints of these acidic Ca2+ stores distinguishes them from other larger Ca2+ sources such as the ER and influx across the plasma membrane. In view of recent advances in the understanding of the modes of operation, we discuss phagocytosis as a template for how endo-lysosomal Ca2+ signals (generated via TPC and TRPML channels) can be integrated in multiple sophisticated ways into biological processes. Phagocytosis illustrates how different endo-lysosomal Ca2+ signals drive different phases of a process, and how these can be altered by disease or infection.
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Affiliation(s)
- Anthony J Morgan
- Department of Pharmacology, University of Oxford, Mansfield Park, Oxford OX1 3QT, UK.
| | - Lianne C Davis
- Department of Pharmacology, University of Oxford, Mansfield Park, Oxford OX1 3QT, UK
| | - Antony Galione
- Department of Pharmacology, University of Oxford, Mansfield Park, Oxford OX1 3QT, UK.
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20
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Yuan Y, Kilpatrick BS, Gerndt S, Bracher F, Grimm C, Schapira AH, Patel S. The lysosomotrope GPN mobilises Ca 2+ from acidic organelles. J Cell Sci 2021; 134:jcs.256578. [PMID: 33602742 PMCID: PMC7972315 DOI: 10.1242/jcs.256578] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Accepted: 01/21/2021] [Indexed: 12/19/2022] Open
Abstract
Lysosomes are acidic Ca2+ stores often mobilised in conjunction with endoplasmic reticulum (ER) Ca2+ stores. Glycyl-L-phenylalanine 2-naphthylamide (GPN) is a widely used lysosomotropic agent that evokes cytosolic Ca2+ signals in many cells. However, whether these signals are the result of a primary action on lysosomes is unclear in light of recent evidence showing that GPN mediates direct ER Ca2+ release through changes in cytosolic pH. Here, we show that GPN evoked rapid increases in cytosolic pH but slower Ca2+ signals. NH4Cl evoked comparable changes in pH but failed to affect Ca2+. The V-type ATPase inhibitor, bafilomycin A1, increased lysosomal pH over a period of hours. Acute treatment modestly affected lysosomal pH and potentiated Ca2+ signals evoked by GPN. In contrast, chronic treatment led to more profound changes in luminal pH and selectively inhibited GPN action. GPN blocked Ca2+ responses evoked by the novel nicotinic acid adenine dinucleotide phosphate-like agonist, TPC2-A1-N. Therefore, GPN-evoked Ca2+ signals were better correlated with associated pH changes in the lysosome compared to the cytosol, and were coupled to lysosomal Ca2+ release. We conclude that Ca2+ signals evoked by GPN most likely derive from acidic organelles. Summary: Methods of releasing calcium from lysosomes are limited but characterization of the effects of GPN in primary cultured human fibroblasts confirmed that it probably targets acidic organelles.
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Affiliation(s)
- Yu Yuan
- Department of Cell and Developmental Biology, UCL, London WC1E 6BT, UK
| | | | - Susanne Gerndt
- Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians University, Munich 81377, Germany
| | - Franz Bracher
- Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians University, Munich 81377, Germany
| | - Christian Grimm
- Walther Straub Institute of Pharmacology and Toxicology, Faculty of Medicine, Ludwig-Maximilians University, Munich 80336, Germany
| | - Anthony H Schapira
- Department of Clinical Neurosciences, UCL Institute of Neurology, London NW3 2PF, UK
| | - Sandip Patel
- Department of Cell and Developmental Biology, UCL, London WC1E 6BT, UK
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21
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Chen CC, Krogsaeter E, Grimm C. Two-pore and TRP cation channels in endolysosomal osmo-/mechanosensation and volume regulation. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2020; 1868:118921. [PMID: 33279607 DOI: 10.1016/j.bbamcr.2020.118921] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Accepted: 11/15/2020] [Indexed: 12/20/2022]
Abstract
Two pore channels (TPCs) and mucolipins (TRPML) are the most prominent cation channels expressed in endolysosomes. Recently, roles of TPCs and TRPML2 have been revealed in regulating and detecting osmotically-driven changes in the surface-to-volume ratio of endolysosomes to promote endocytic and recycling traffic. TPCs and TRPML2 are highly expressed in macrophages and contribute to immune cell function. Here, we provide an overview of the emerging roles of these channels in innate immune cells, in particular macrophages, and highlight two models for osmo-mechanical regulation of intracellular organelle volume, trafficking, and cell homeostasis involving either TPCs or TRPML2.
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Affiliation(s)
- Cheng-Chang Chen
- Department of Pharmacy, Center for Drug Research, Ludwig-Maximilians-Universität, Munich, Germany; Department of Clinical Laboratory Sciences and Medical Biotechnology, College of Medicine, National Taiwan University, Taipei, Taiwan.
| | - Einar Krogsaeter
- Walther Straub Institute of Pharmacology and Toxicology, Faculty of Medicine, Ludwig-Maximilians-Universität, Munich, Germany
| | - Christian Grimm
- Walther Straub Institute of Pharmacology and Toxicology, Faculty of Medicine, Ludwig-Maximilians-Universität, Munich, Germany.
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22
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Patel S, Malmberg KJ. Preventing a shock to the system. Two-pore channel 1 negatively regulates anaphylaxis. Cell Calcium 2020; 92:102289. [PMID: 33027744 DOI: 10.1016/j.ceca.2020.102289] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Revised: 09/13/2020] [Accepted: 09/13/2020] [Indexed: 12/29/2022]
Abstract
The mammalian two-pore channels TPC1 and TPC2 are patho-physiologically relevant endo-lysosomal cation channels regulated by the Ca2+ mobilising messenger NAADP and the phosphoinositide PI(3,5)P2. Recent work by Arlt et al shows that genetic or chemical inhibition of TPC1 in mice promotes anaphylaxis in vivo through a mechanism involving enhanced endoplasmic reticulum Ca2+ release and secretion in mast cells.
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Affiliation(s)
- Sandip Patel
- Department of Cell and Developmental Biology, University College London, Gower Street, London, WC1E 6BT, UK.
| | - Karl-Johan Malmberg
- Institute of Clinical Medicine, University of Oslo, 0318, Oslo, Norway; Department of Cancer Immunology, Institute for Cancer Research, Oslo University Hospital, 0310, Oslo, Norway; Center for Infectious Medicine, Department of Medicine Huddinge, Karolinska Institutet, 14186, Stockholm, Sweden
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