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Uchida K. TRPM3, TRPM4, and TRPM5 as thermo-sensitive channels. J Physiol Sci 2024; 74:43. [PMID: 39294615 PMCID: PMC11409758 DOI: 10.1186/s12576-024-00937-0] [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: 06/29/2024] [Accepted: 09/01/2024] [Indexed: 09/20/2024]
Abstract
Temperature detection is essential for the survival and perpetuation of any species. Thermoreceptors in the skin sense body temperature as well as the temperatures of ambient air and objects. Since Dr. David Julius and his colleagues discovered that TRPV1 is expressed in small-diameter primary sensory neurons, and activated by temperatures above 42 °C, 11 of thermo-sensitive TRP channels have been identified. TRPM3 expressed in sensory neurons acts as a sensor for noxious heat. TRPM4 and TRPM5 are Ca2⁺-activated monovalent cation channels, and their activity is drastically potentiated by temperature increase. This review aims to summarize the expression patterns, electrophysiological properties, and physiological roles of TRPM3, TRPM4, and TRPM5 associated with thermosensation.
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Affiliation(s)
- Kunitoshi Uchida
- Laboratory of Functional Physiology, Department of Environmental and Life Sciences, School of Food and Nutritional Sciences, University of Shizuoka, Yada 52-1, Suruga-Ku, Shizuoka, Shizuoka, 422-8526, Japan.
- Graduate School of Integrated Pharmaceutical and Nutritional Sciences, University of Shizuoka, Shizuoka, Japan.
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Liu H, Fu M, Zhang Y, You Q, Wang L. Small molecules targeting canonical transient receptor potential channels: an update. Drug Discov Today 2024; 29:103951. [PMID: 38514041 DOI: 10.1016/j.drudis.2024.103951] [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: 10/25/2023] [Revised: 03/06/2024] [Accepted: 03/14/2024] [Indexed: 03/23/2024]
Abstract
Transient receptor potential canonical (TRPC) channels belong to an important class of non-selective cation channels. This channel family consists of multiple members that widely participate in various physiological and pathological processes. Previous studies have uncovered the intricate regulation of these channels, as well as the spatial arrangement of TRPCs and the binding sites for various small molecule compounds. Multiple small molecules have been identified as selective agonists or inhibitors targeting different subtypes of TRPC, including potential preclinical drug candidates. This review covers recent advancements in the understanding of TRPC regulation and structure and the discovery of TRPC small molecules over the past few years, with the aim of facilitating research on TRPCs and small-molecule drug discovery.
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Affiliation(s)
- Hua Liu
- State Key Laboratory of Natural Medicines and Jiangsu Key Laboratory of Drug Design and Optimization, China Pharmaceutical University, Nanjing 210009, China; Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, Nanjing 210009, China
| | - Min Fu
- State Key Laboratory of Natural Medicines and Jiangsu Key Laboratory of Drug Design and Optimization, China Pharmaceutical University, Nanjing 210009, China; Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, Nanjing 210009, China
| | - Yifan Zhang
- State Key Laboratory of Natural Medicines and Jiangsu Key Laboratory of Drug Design and Optimization, China Pharmaceutical University, Nanjing 210009, China; Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, Nanjing 210009, China
| | - Qidong You
- State Key Laboratory of Natural Medicines and Jiangsu Key Laboratory of Drug Design and Optimization, China Pharmaceutical University, Nanjing 210009, China; Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, Nanjing 210009, China.
| | - Lei Wang
- State Key Laboratory of Natural Medicines and Jiangsu Key Laboratory of Drug Design and Optimization, China Pharmaceutical University, Nanjing 210009, China; Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, Nanjing 210009, China.
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Apolipoprotein C3 facilitates internalization of cationic lipid nanoparticles into bone marrow-derived mouse mast cells. Sci Rep 2023; 13:431. [PMID: 36624108 PMCID: PMC9828384 DOI: 10.1038/s41598-022-25737-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Accepted: 12/05/2022] [Indexed: 01/11/2023] Open
Abstract
Mast cells (MCs), are hematopoetically-derived secretory immune cells that release preformed as well as de novo synthesized inflammatory mediators in response to activation by several stimuli. Based on their role in inflammatory responses, particularly in the lung and skin, MCs provide an effective target for anti-inflammatory therapeutic strategies. Drug-delivery of lipophilic payloads to MCs can be challenging due to their functionally distinct intracellular structures. In the present study, pH-sensitive cationic lipid-based nanoparticles (LNPs) composed of DODMA, DODAP or DOTAP lipids that encapsulated a GFP or eGFP plasmid were constructed using non-turbulent microfluidic mixing. This approach achieved up to 75-92% encapsulation efficiency. Dynamic light scattering revealed a uniformly sized and homogeneous dispersion of LNPs. To promote cellular internalization, LNPs were complexed with apolipoproteins, amphipathic proteins capable of binding lipids and facilitating their transport into cells. Cryo-TEM analysis showed that LNP structure was differentially modified when associated with different types of apolipoproteins. LNP preparations made up of DODMA or DODMA, DODAP and DOTAP lipids were coated with seven apolipoproteins (Apo A1, B, C3, D, E2, E4 and H). Differentiated bone-marrow derived mouse mast cells (BMMCs) were exposed to apolipoprotein-LNP and internalization was measured using flow cytometry. Out of all the apolipoproteins tested, ApoC3 most efficiently facilitated cellular internalization of the LNP into BMMCs as determined by GFP fluorescence using flow cytometry. These effects were confirmed in a less differentiated but also interleukin-3-dependent model of mouse mast cells, MC/9. ApoC3-LNP enhanced internalization by BMMC in a concentration-dependent manner and this was significantly increased when BMMC were pre-treated with inhibitors of actin polymerization, suggesting a dependence on intracellular shuttling. Activation of peroxisome proliferator-activated receptor gamma (PPARγ) decreased ApoC3-LNP internalization and reduced the expression of apolipoprotein E receptor 2 (ApoER2), suggesting that ApoC3-LNP binding to ApoER2 may be responsible for its enhanced internalization. Furthermore, ApoC3 fails to facilitate internalization of LNPs in Lrp8-/- KO BMMC that do not express ApoER2 on their cell surface. Altogether, our studies reveal an important role of ApoC3 in facilitating internalization of cationic LNPs into MCs.
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Zhou Y, Xu J, Hou Y, Bekris L, Leverenz JB, Pieper AA, Cummings J, Cheng F. The Alzheimer's Cell Atlas (TACA): A single-cell molecular map for translational therapeutics accelerator in Alzheimer's disease. ALZHEIMER'S & DEMENTIA (NEW YORK, N. Y.) 2022; 8:e12350. [PMID: 36254161 PMCID: PMC9558163 DOI: 10.1002/trc2.12350] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Revised: 08/01/2022] [Accepted: 08/15/2022] [Indexed: 12/30/2022]
Abstract
Introduction Recent advances in generating massive single-cell/nucleus transcriptomic data have shown great potential for facilitating the identification of cell type-specific Alzheimer's disease (AD) pathobiology and drug-target discovery for therapeutic development. Methods We developed The Alzheimer's Cell Atlas (TACA) by compiling an AD brain cell atlas consisting of over 1.1 million cells/nuclei across 26 data sets, covering major brain regions (hippocampus, cerebellum, prefrontal cortex, and so on) and cell types (astrocyte, microglia, neuron, oligodendrocytes, and so on). We conducted nearly 1400 differential expression comparisons to identify cell type-specific molecular alterations (e.g., case vs healthy control, sex-specific, apolipoprotein E (APOE) ε4/ε4, and TREM2 mutations). Each comparison was followed by protein-protein interaction module detection, functional enrichment analysis, and omics-informed target and drug (over 700,000 perturbation profiles) screening. Over 400 cell-cell interaction analyses using 6000 ligand-receptor interactions were conducted to identify the cell-cell communication networks in AD. Results All results are integrated into TACA (https://taca.lerner.ccf.org/), a new web portal with cell type-specific, abundant transcriptomic information, and 12 interactive visualization tools for AD. Discussion We envision that TACA will be a highly valuable resource for both basic and translational research in AD, as it provides abundant information for AD pathobiology and actionable systems biology tools for drug discovery. Highlights We compiled an Alzheimer's disease (AD) brain cell atlas consisting of more than 1.1 million cells/nuclei transcriptomes from 26 data sets, covering major brain regions (cortex, hippocampus, cerebellum) and cell types (e.g., neuron, oligodendrocyte, astrocyte, and microglia).We conducted over 1400 differential expression (DE) comparisons to identify cell type-specific gene expression alterations. Major comparison types are (1) AD versus healthy control; (2) sex-specific DE, (3) genotype-driven DE (i.e., apolipoprotein E [APOE] ε4/ε4 vs APOE ε3/ε3; TREM2R47H vs common variants) analysis; and (4) others. Each comparison was further followed by (1) human protein-protein interactome network module analysis, (2) pathway enrichment analysis, and (3) gene-set enrichment analysis.For drug screening, we conducted gene set enrichment analysis for all the comparisons with over 700,000 drug perturbation profiles connecting more than 10,000 human genes and 13,000 drugs/compounds.A total of over 400 analyses of cell-cell interactions against 6000 experimentally validated ligand-receptor interactions were conducted to reveal the disease-relevant cell-cell communications in AD.
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Affiliation(s)
- Yadi Zhou
- Genomic Medicine InstituteLerner Research InstituteCleveland ClinicClevelandOhioUSA
| | - Jielin Xu
- Genomic Medicine InstituteLerner Research InstituteCleveland ClinicClevelandOhioUSA
| | - Yuan Hou
- Genomic Medicine InstituteLerner Research InstituteCleveland ClinicClevelandOhioUSA
| | - Lynn Bekris
- Genomic Medicine InstituteLerner Research InstituteCleveland ClinicClevelandOhioUSA
- Department of Molecular MedicineCleveland Clinic Lerner College of MedicineCase Western Reserve UniversityClevelandOhioUSA
| | - James B. Leverenz
- Department of Molecular MedicineCleveland Clinic Lerner College of MedicineCase Western Reserve UniversityClevelandOhioUSA
- Lou Ruvo Center for Brain HealthNeurological InstituteCleveland ClinicClevelandOhioUSA
| | - Andrew A. Pieper
- Harrington Discovery InstituteUniversity Hospitals Cleveland Medical CenterClevelandOhioUSA
- Department of PsychiatryCase Western Reserve UniversityClevelandOhioUSA
- Geriatric Psychiatry, GRECCLouis Stokes Cleveland VA Medical CenterClevelandOhioUSA
- Institute for Transformative Molecular MedicineSchool of MedicineCase Western Reserve UniversityClevelandOhioUSA
- Department of NeuroscienceCase Western Reserve UniversitySchool of MedicineClevelandOhioUSA
| | - Jeffrey Cummings
- Chambers‐Grundy Center for Transformative NeurosciencePam Quirk Brain Health and Biomarker LaboratoryDepartment of Brain HealthSchool of Integrated Health SciencesUniversity of Nevada Las VegasLas VegasNevadaUSA
| | - Feixiong Cheng
- Genomic Medicine InstituteLerner Research InstituteCleveland ClinicClevelandOhioUSA
- Department of Molecular MedicineCleveland Clinic Lerner College of MedicineCase Western Reserve UniversityClevelandOhioUSA
- Case Comprehensive Cancer CenterCase Western Reserve University School of MedicineClevelandOhioUSA
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Zhang M, Hu M, Alles SRA, Montera MA, Adams I, Santi MD, Inoue K, Tu NH, Westlund KN, Ye Y. Peroxisome proliferator-activated receptor gamma agonist ELB00824 suppresses oxaliplatin-induced pain, neuronal hypersensitivity, and oxidative stress. Neuropharmacology 2022; 218:109233. [PMID: 36007855 DOI: 10.1016/j.neuropharm.2022.109233] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2022] [Revised: 08/12/2022] [Accepted: 08/17/2022] [Indexed: 11/29/2022]
Abstract
Chemotherapy-induced neuropathic pain (CINP) is a debilitating and difficult-to-treat side effect of chemotherapeutic drugs. CINP is marked with oxidative stress and neuronal hypersensitivities. The peroxisome proliferator-activated receptor gamma (PPARγ) is a transcription factor that regulates genes involved in oxidative stress and inflammation. We hypothesize that PPARγ agonists are protective against CIPN by reducing oxidative stress and inhibiting neuronal hypersensitivities. To test our hypothesis, acute or chronic CIPN was introduced by short or long-term treatment of oxaliplatin in BALB/c mice. CIPN mice were treated with either a novel blood-brain barrier (BBB) penetrable PPARγ agonist ELB00824, or a BBB non-penetrable PPARγ agonist pioglitazone, or vehicle. Cold allodynia, mechanical allodynia, motor coordination, sedation and addiction were measured with dry ice, von Frey filaments, beam-walking tests, and conditioned place preference, respectively. Oxidative stress was accessed by measuring byproducts of protein oxidation (carbonyl and 3-Nitrotyrosine) and lipid peroxidation [Thiobarbituric acid reactive substances (TBARS)], as wells as gene expression of Cat, Sod2, Ppargc1a. The effects of ELB00824 on nociceptor excitability were measured using whole-cell electrophysiology of isolated dorsal root ganglion neurons. Preemptive ELB00824, but not pioglitazone, reduced oxaliplatin-induced cold and mechanical allodynia and oxidative stress. ELB0824 suppressed oxaliplatin-induced firing in IB4- neurons. ELB00824 did not cause motor discoordination or sedation/addiction or reduce the antineoplastic activity of oxaliplatin (measured with an MTS-based cell proliferation assay) in a human colon cancer cell line (HCT116) and a human oral cancer cell line (HSC-3). Our results demonstrated that ELB00824 prevents oxaliplatin-induced pain, likely via inhibiting neuronal hypersensitivities and oxidative stress.
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Affiliation(s)
- Morgan Zhang
- Bluestone Center for Clinical Research, New York University College of Dentistry, 421 First Avenue, 233W, New York, NY, 10010, USA; Department of Molecular Pathobiology, New York University College of Dentistry, 345 E. 24th street, New York, NY, 10010, USA; USA Elixiria Biotech Inc, Hartsdale, NY, 10530, USA; Shanghai Elixiria Biotech Co. Ltd, 578 Yingkou Road, Yangpu District, Shanghai, 200433, China
| | - Min Hu
- Shanghai Elixiria Biotech Co. Ltd, 578 Yingkou Road, Yangpu District, Shanghai, 200433, China
| | - Sascha R A Alles
- Department of Anesthesiology & Critical Care Medicine, MSC10 6000, 2211 Lomas Blvd. NE, University of New Mexico Health Sciences Center, Albuquerque, NM, 87131, USA
| | - Marena A Montera
- Department of Anesthesiology & Critical Care Medicine, MSC10 6000, 2211 Lomas Blvd. NE, University of New Mexico Health Sciences Center, Albuquerque, NM, 87131, USA
| | - Ian Adams
- Department of Anesthesiology & Critical Care Medicine, MSC10 6000, 2211 Lomas Blvd. NE, University of New Mexico Health Sciences Center, Albuquerque, NM, 87131, USA
| | - Maria D Santi
- Bluestone Center for Clinical Research, New York University College of Dentistry, 421 First Avenue, 233W, New York, NY, 10010, USA; Department of Molecular Pathobiology, New York University College of Dentistry, 345 E. 24th street, New York, NY, 10010, USA
| | - Kenji Inoue
- Bluestone Center for Clinical Research, New York University College of Dentistry, 421 First Avenue, 233W, New York, NY, 10010, USA; Department of Molecular Pathobiology, New York University College of Dentistry, 345 E. 24th street, New York, NY, 10010, USA
| | - Nguyen Huu Tu
- Bluestone Center for Clinical Research, New York University College of Dentistry, 421 First Avenue, 233W, New York, NY, 10010, USA; Department of Molecular Pathobiology, New York University College of Dentistry, 345 E. 24th street, New York, NY, 10010, USA
| | - Karin N Westlund
- Department of Anesthesiology & Critical Care Medicine, MSC10 6000, 2211 Lomas Blvd. NE, University of New Mexico Health Sciences Center, Albuquerque, NM, 87131, USA
| | - Yi Ye
- Bluestone Center for Clinical Research, New York University College of Dentistry, 421 First Avenue, 233W, New York, NY, 10010, USA; Department of Molecular Pathobiology, New York University College of Dentistry, 345 E. 24th street, New York, NY, 10010, USA.
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Association of protein function-altering variants with cardiometabolic traits: the strong heart study. Sci Rep 2022; 12:9317. [PMID: 35665752 PMCID: PMC9167281 DOI: 10.1038/s41598-022-12866-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2022] [Accepted: 05/05/2022] [Indexed: 11/08/2022] Open
Abstract
Clinical and biomarker phenotypic associations for carriers of protein function-altering variants may help to elucidate gene function and health effects in populations. We genotyped 1127 Strong Heart Family Study participants for protein function-altering single nucleotide variants (SNV) and indels selected from a low coverage whole exome sequencing of American Indians. We tested the association of each SNV/indel with 35 cardiometabolic traits. Among 1206 variants (average minor allele count = 20, range of 1 to 1064), ~ 43% were not present in publicly available repositories. We identified seven SNV-trait significant associations including a missense SNV at ABCA10 (rs779392624, p = 8 × 10-9) associated with fasting triglycerides, which gene product is involved in macrophage lipid homeostasis. Among non-diabetic individuals, missense SNVs at four genes were associated with fasting insulin adjusted for BMI (PHIL, chr6:79,650,711, p = 2.1 × 10-6; TRPM3, rs760461668, p = 5 × 10-8; SPTY2D1, rs756851199, p = 1.6 × 10-8; and TSPO, rs566547284, p = 2.4 × 10-6). PHIL encoded protein is involved in pancreatic β-cell proliferation and survival, and TRPM3 protein mediates calcium signaling in pancreatic β-cells in response to glucose. A genetic risk score combining increasing insulin risk alleles of these four genes was associated with 53% (95% confidence interval 1.09, 2.15) increased odds of incident diabetes and 83% (95% confidence interval 1.35, 2.48) increased odds of impaired fasting glucose at follow-up. Our study uncovered novel gene-trait associations through the study of protein-coding variants and demonstrates the advantages of association screenings targeting diverse and high-risk populations to study variants absent in publicly available repositories.
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Fallah HP, Ahuja E, Lin H, Qi J, He Q, Gao S, An H, Zhang J, Xie Y, Liang D. A Review on the Role of TRP Channels and Their Potential as Drug Targets_An Insight Into the TRP Channel Drug Discovery Methodologies. Front Pharmacol 2022; 13:914499. [PMID: 35685622 PMCID: PMC9170958 DOI: 10.3389/fphar.2022.914499] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Accepted: 04/27/2022] [Indexed: 01/13/2023] Open
Abstract
Transient receptor potential (TRP) proteins are a large group of ion channels that control many physiological functions in our body. These channels are considered potential therapeutic drug targets for various diseases such as neurological disorders, cancers, cardiovascular disease, and many more. The Nobel Prize in Physiology/Medicine in the year 2021 was awarded to two scientists for the discovery of TRP and PIEZO ion channels. Improving our knowledge of technologies for their study is essential. In the present study, we reviewed the role of TRP channel types in the control of normal physiological functions as well as disease conditions. Also, we discussed the current and novel technologies that can be used to study these channels successfully. As such, Flux assays for detecting ionic flux through ion channels are among the core and widely used tools for screening drug compounds. Technologies based on these assays are available in fully automated high throughput set-ups and help detect changes in radiolabeled or non-radiolabeled ionic flux. Aurora's Ion Channel Reader (ICR), which works based on label-free technology of flux assay, offers sensitive, accurate, and reproducible measurements to perform drug ranking matching with patch-clamp (gold standard) data. The non-radiolabeled trace-based flux assay coupled with the ICR detects changes in various ion types, including potassium, calcium, sodium, and chloride channels, by using appropriate tracer ions. This technology is now considered one of the very successful approaches for analyzing ion channel activity in modern drug discovery. It could be a successful approach for studying various ion channels and transporters, including the different members of the TRP family of ion channels.
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Affiliation(s)
| | - Ekta Ahuja
- Aurora Biomed Inc., Vancouver, BC, Canada
| | | | - Jinlong Qi
- Department of Pharmacology, Hebei Medical University, Shijiazhuang, China
| | - Qian He
- Aurora Discovery Inc., Foshan, China
| | - Shan Gao
- Aurora Discovery Inc., Foshan, China
| | | | | | | | - Dong Liang
- Aurora Biomed Inc., Vancouver, BC, Canada
- Aurora Discovery Inc., Foshan, China
- Guangzhou Institute of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
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Chappe Y, Michel P, Joushomme A, Barbeau S, Pierredon S, Baron L, Garenne A, Poulletier De Gannes F, Hurtier A, Mayer S, Lagroye I, Quignard JF, Ducret T, Compan V, Franchet C, Percherancier Y. High-throughput screening of TRPV1 ligands in the light of the Bioluminescence Resonance Energy Transfer technique. Mol Pharmacol 2021; 100:237-257. [PMID: 34127538 DOI: 10.1124/molpharm.121.000271] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Accepted: 05/17/2021] [Indexed: 11/22/2022] Open
Abstract
Ion channels are attractive drug targets for many therapeutic applications. However, high-throughput screening (HTS) of drug candidates is difficult and remains very expensive. We thus assessed the suitability of the Bioluminescence Resonance Energy Transfer (BRET) technique as a new HTS method for ion-channel studies by taking advantage of our recently characterized intra- and intermolecular BRET probes targeting the TRPV1 ion channel. These BRET probes monitor conformational changes during TRPV1 gating and subsequent coupling with Calmodulin, two molecular events that are intractable using reference techniques such as automated calcium assay (ACA) and automated patch-clamp (APC). We screened the small-sized Prestwick chemical library, encompassing 1200 compounds with high structural diversity, using either intra- and intermolecular BRET probes or ACA. Secondary screening of the detected hits was done using APC. Multiparametric analysis of our results shed light on the capability of calmodulin inhibitors included in the Prestwick library to inhibit TRPV1 activation by Capsaicin (CAPS). BRET was the lead technique for this identification process. Finally, we present data exemplifying the use of intramolecular BRET probes to study other TRPs and non-TRPs ion channels. Knowing the ease of use of BRET biosensors and the low cost of the BRET technique, these assays may advantageously be included for extending ion-channel drug screening. Significance Statement We screened a chemical library against TRPV1 ion channel using Bioluminescence Resonance Energy Transfer (BRET) molecular probes, and compared the results with the ones obtained using reference techniques such as automated calcium assay and automated patch-clamp. Multiparametric analysis of our results shed light on the capability of Calmodulin antagonists to inhibit chemical activation of TRPV1, and indicates that BRET probes may advantageously be included in ion channel drug screening campaigns.
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Affiliation(s)
- Yann Chappe
- IMS laboratory / CNRS UMR 5218, Bordeaux University, France
| | | | | | - Solène Barbeau
- Centre de Recherche Cardio-Thoracique de Bordeaux, INSERM U1045, Bordeaux University, France
| | - Sandra Pierredon
- CNRS UMR 5203 - INSERM U1191, Institut de Genomique Fonctionnelle, France
| | | | - André Garenne
- IMS laboratory / CNRS UMR 5218, Bordeaux University, France
| | | | | | | | | | - Jean-François Quignard
- Centre de Recherche Cardio-Thoracique de Bordeaux, INSERM U1045, Bordeaux University, France
| | - Thomas Ducret
- Centre de Recherche Cardio-Thoracique de Bordeaux, INSERM U1045, Bordeaux University, France
| | - Vincent Compan
- CNRS UMR 5203 - INSERM U1191, Institut de Genomique Fonctionnelle, France
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Canonical transient receptor potential channels and their modulators: biology, pharmacology and therapeutic potentials. Arch Pharm Res 2021; 44:354-377. [PMID: 33763843 PMCID: PMC7989688 DOI: 10.1007/s12272-021-01319-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2020] [Accepted: 03/14/2021] [Indexed: 12/17/2022]
Abstract
Canonical transient receptor potential channels (TRPCs) are nonselective, high calcium permeability cationic channels. The TRPCs family includes TRPC1, TRPC2, TRPC3, TRPC4, TRPC5, TRPC6, and TRPC7. These channels are widely expressed in the cardiovascular and nervous systems and exist in many other human tissues and cell types, playing several crucial roles in the human physiological and pathological processes. Hence, the emergence of TRPCs modulators can help investigate these channels’ applications in health and disease. It is worth noting that the TRPCs subfamilies have structural and functional similarities, which presents a significant difficulty in screening and discovering of TRPCs modulators. In the past few years, only a limited number of selective modulators of TRPCs were detected; thus, additional research on more potent and more selective TRPCs modulators is needed. The present review focuses on the striking desired therapeutic effects of TRPCs modulators, which provides intel on the structural modification of TRPCs modulators and further pharmacological research. Importantly, TRPCs modulators can significantly facilitate future studies of TRPCs and TRPCs related diseases.
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Shiels A. TRPM3_miR-204: a complex locus for eye development and disease. Hum Genomics 2020; 14:7. [PMID: 32070426 PMCID: PMC7027284 DOI: 10.1186/s40246-020-00258-4] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Accepted: 02/06/2020] [Indexed: 02/07/2023] Open
Abstract
First discovered in a light-sensitive retinal mutant of Drosophila, the transient receptor potential (TRP) superfamily of non-selective cation channels serve as polymodal cellular sensors that participate in diverse physiological processes across the animal kingdom including the perception of light, temperature, pressure, and pain. TRPM3 belongs to the melastatin sub-family of TRP channels and has been shown to function as a spontaneous calcium channel, with permeability to other cations influenced by alternative splicing and/or non-canonical channel activity. Activators of TRPM3 channels include the neurosteroid pregnenolone sulfate, calmodulin, phosphoinositides, and heat, whereas inhibitors include certain drugs, plant-derived metabolites, and G-protein subunits. Activation of TRPM3 channels at the cell membrane elicits a signal transduction cascade of mitogen-activated kinases and stimulus response transcription factors. The mammalian TRPM3 gene hosts a non-coding microRNA gene specifying miR-204 that serves as both a tumor suppressor and a negative regulator of post-transcriptional gene expression during eye development in vertebrates. Ocular co-expression of TRPM3 and miR-204 is upregulated by the paired box 6 transcription factor (PAX6) and mutations in all three corresponding genes underlie inherited forms of eye disease in humans including early-onset cataract, retinal dystrophy, and coloboma. This review outlines the genomic and functional complexity of the TRPM3_miR-204 locus in mammalian eye development and disease.
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Affiliation(s)
- Alan Shiels
- Ophthalmology and Visual Sciences, Washington University School of Medicine, 660 S. Euclid Ave., Box 8096, St. Louis, MO, 63110, USA.
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Behrendt M. Transient receptor potential channels in the context of nociception and pain - recent insights into TRPM3 properties and function. Biol Chem 2020; 400:917-926. [PMID: 30844758 DOI: 10.1515/hsz-2018-0455] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Accepted: 02/25/2019] [Indexed: 01/09/2023]
Abstract
Potential harmful stimuli like heat, mechanical pressure or chemicals are detected by specialized cutaneous nerve fiber endings of nociceptor neurons in a process called nociception. Acute stimulation results in immediate protective reflexes and pain sensation as a normal, physiological behavior. However, ongoing (chronic) pain is a severe pathophysiological condition with diverse pathogeneses that is clinically challenging because of limited therapeutic options. Therefore, an urgent need exists for new potent and specific analgesics without afflicting adverse effects. Recently, TRPM3, a member of the superfamily of transient receptor potential (TRP) ion channels, has been shown to be expressed in nociceptors and to be involved in the detection of noxious heat (acute pain) as well as inflammatory hyperalgesia (acute and chronic pain). Current results in TRPM3 research indicate that this ion channel might not only be part of yet unraveled mechanisms underlying chronic pain but also has the potential to become a clinically relevant pharmacological target of future analgesic strategies. The aim of this review is to summarize and present the basic features of TRPM3 proteins and channels, to highlight recent findings and developments and to provide an outlook on emerging directions of TRPM3 research in the field of chronic pain.
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Affiliation(s)
- Marc Behrendt
- Experimental Pain Research, Heidelberg University, Medical Faculty Mannheim, CBTM, Tridomus, Building C, Ludolf-Krehl-Straße 13-17, D-68167 Mannheim, Germany
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Cabanas H, Muraki K, Balinas C, Eaton-Fitch N, Staines D, Marshall-Gradisnik S. Validation of impaired Transient Receptor Potential Melastatin 3 ion channel activity in natural killer cells from Chronic Fatigue Syndrome/ Myalgic Encephalomyelitis patients. Mol Med 2019; 25:14. [PMID: 31014226 PMCID: PMC6480905 DOI: 10.1186/s10020-019-0083-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Accepted: 04/05/2019] [Indexed: 02/07/2023] Open
Abstract
Background Chronic Fatigue Syndrome/ Myalgic Encephalomyelitis (CFS/ME) is a complex multifactorial disorder of unknown cause having multi-system manifestations. Although the aetiology of CFS/ME remains elusive, immunological dysfunction and more particularly reduced cytotoxic activity in natural killer (NK) cells is the most consistent laboratory finding. The Transient Receptor Potential (TRP) superfamily of cation channels play a pivotal role in the pathophysiology of immune diseases and are therefore potential therapeutic targets. We have previously identified single nucleotide polymorphisms in TRP genes in peripheral NK cells from CFS/ME patients. We have also described biochemical pathway changes and calcium signaling perturbations in NK cells from CFS/ME patients. Notably, we have previously reported a decrease of TRP cation channel subfamily melastatin member 3 (TRPM3) function in NK cells isolated from CFS/ME patients compared with healthy controls after modulation with pregnenolone sulfate and ononetin using a patch-clamp technique. In the present study, we aim to confirm the previous results describing an impaired TRPM3 activity in a new cohort of CFS/ME patients using a whole cell patch-clamp technique after modulation with reversible TRPM3 agonists, pregnenolone sulfate and nifedipine, and an effective TRPM3 antagonist, ononetin. Indeed, no formal research has commented on using pregnenolone sulfate or nifedipine to treat CFS/ME patients while there is evidence that clinicians prescribe calcium channel blockers to improve different symptoms. Methods Whole-cell patch-clamp technique was used to measure TRPM3 activity in isolated NK cells from twelve age- and sex-matched healthy controls and CFS/ME patients, after activation with pregnenolone sulfate and nifedipine and inhibition with ononetin. Results We confirmed a significant reduction in amplitude of TRPM3 currents after pregnenolone sulfate stimulation in isolated NK cells from another cohort of CFS/ME patients compared with healthy controls. The pregnenolone sulfate-evoked ionic currents through TRPM3 channels were again significantly modulated by ononetin in isolated NK cells from healthy controls compared with CFS/ME patients. In addition, we used nifedipine, another reversible TRPM3 agonist to support the previous findings and found similar results confirming a significant loss of the TRPM3 channel activity in CFS/ME patients. Conclusions Impaired TRPM3 activity was validated in NK cells isolated from CFS/ME patients using different pharmacological tools and whole-cell patch-clamp technique as the gold standard for ion channel research. This investigation further helps to establish TRPM3 channels as a prognostic marker and/ or a potential therapeutic target for CFS/ME.
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Affiliation(s)
- H Cabanas
- School of Medical Science, Griffith University, Gold Coast, QLD, Australia. .,The National Centre for Neuroimmunology and Emerging Diseases, Menzies Health Institute Queensland, Griffith University, Gold Coast, Southport, QLD, 4222, Australia. .,Consortium Health International for Myalgic Encephalomyelitis, National Centre for Neuroimmunology and Emerging Diseases, Griffith University, Gold Coast, QLD, Australia.
| | - K Muraki
- Laboratory of Cellular Pharmacology, School of Pharmacy, Aichi-Gakuin University, Chikusa, Nagoya, Japan.,Consortium Health International for Myalgic Encephalomyelitis, National Centre for Neuroimmunology and Emerging Diseases, Griffith University, Gold Coast, QLD, Australia
| | - C Balinas
- School of Medical Science, Griffith University, Gold Coast, QLD, Australia.,The National Centre for Neuroimmunology and Emerging Diseases, Menzies Health Institute Queensland, Griffith University, Gold Coast, Southport, QLD, 4222, Australia.,Consortium Health International for Myalgic Encephalomyelitis, National Centre for Neuroimmunology and Emerging Diseases, Griffith University, Gold Coast, QLD, Australia
| | - N Eaton-Fitch
- School of Medical Science, Griffith University, Gold Coast, QLD, Australia.,The National Centre for Neuroimmunology and Emerging Diseases, Menzies Health Institute Queensland, Griffith University, Gold Coast, Southport, QLD, 4222, Australia.,Consortium Health International for Myalgic Encephalomyelitis, National Centre for Neuroimmunology and Emerging Diseases, Griffith University, Gold Coast, QLD, Australia
| | - D Staines
- School of Medical Science, Griffith University, Gold Coast, QLD, Australia.,The National Centre for Neuroimmunology and Emerging Diseases, Menzies Health Institute Queensland, Griffith University, Gold Coast, Southport, QLD, 4222, Australia.,Consortium Health International for Myalgic Encephalomyelitis, National Centre for Neuroimmunology and Emerging Diseases, Griffith University, Gold Coast, QLD, Australia
| | - S Marshall-Gradisnik
- School of Medical Science, Griffith University, Gold Coast, QLD, Australia.,The National Centre for Neuroimmunology and Emerging Diseases, Menzies Health Institute Queensland, Griffith University, Gold Coast, Southport, QLD, 4222, Australia.,Consortium Health International for Myalgic Encephalomyelitis, National Centre for Neuroimmunology and Emerging Diseases, Griffith University, Gold Coast, QLD, Australia
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13
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Ali ES, Petrovsky N. Calcium Signaling As a Therapeutic Target for Liver Steatosis. Trends Endocrinol Metab 2019; 30:270-281. [PMID: 30850262 DOI: 10.1016/j.tem.2019.02.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/25/2018] [Revised: 02/06/2019] [Accepted: 02/07/2019] [Indexed: 12/13/2022]
Abstract
Hepatic steatosis, the first step in nonalcoholic fatty liver disease (NAFLD), can arise from various pathophysiological conditions. While lipid metabolism in the liver is normally balanced such that there is no excessive lipid accumulation, when this homeostasis is disrupted lipid droplets (LDs) accumulate in hepatocytes resulting in cellular toxicity. The mechanisms underlying this accumulation and the subsequent hepatocellular damage are multifactorial and poorly understood, with the result that there are no currently approved treatments for NAFLD. Impaired calcium signaling has recently been identified as a cause of increased endoplasmic reticulum (ER) stress contributing to hepatic lipid accumulation. This review highlights new findings on the role of impaired Ca2+ signaling in the development of steatosis and discusses potential new approaches to NAFLD treatment based on these new insights.
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Affiliation(s)
- Eunüs S Ali
- College of Medicine and Public Health, Flinders University, Adelaide, SA, Australia
| | - Nikolai Petrovsky
- College of Medicine and Public Health, Flinders University, Adelaide, SA, Australia; Vaxine Pty Ltd, 11 Walkley Avenue, Warradale, Adelaide, SA, Australia.
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14
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Rubaiy HN. Treasure troves of pharmacological tools to study transient receptor potential canonical 1/4/5 channels. Br J Pharmacol 2019; 176:832-846. [PMID: 30656647 PMCID: PMC6433652 DOI: 10.1111/bph.14578] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Revised: 11/25/2018] [Accepted: 12/18/2018] [Indexed: 12/13/2022] Open
Abstract
Canonical or classical transient receptor potential 4 and 5 proteins (TRPC4 and TRPC5) assemble as homomers or heteromerize with TRPC1 protein to form functional nonselective cationic channels with high calcium permeability. These channel complexes, TRPC1/4/5, are widely expressed in nervous and cardiovascular systems, also in other human tissues and cell types. It is debatable that TRPC1 protein is able to form a functional ion channel on its own. A recent explosion of molecular information about TRPC1/4/5 has emerged including knowledge of their distribution, function, and regulation suggesting these three members of the TRPC subfamily of TRP channels play crucial roles in human physiology and pathology. Therefore, these ion channels represent potential drug targets for cancer, epilepsy, anxiety, pain, and cardiac remodelling. In recent years, a number of highly selective small-molecule modulators of TRPC1/4/5 channels have been identified as being potent with improved pharmacological properties. This review will focus on recent remarkable small-molecule agonists: (-)-englerin A and tonantzitlolone and antagonists: Pico145 and HC7090, of TPRC1/4/5 channels. In addition, this work highlights other recently identified modulators of these channels such as the benzothiadiazine derivative, riluzole, ML204, clemizole, and AC1903. Together, these treasure troves of agonists and antagonists of TRPC1/4/5 channels provide valuable hints to comprehend the functional importance of these ion channels in native cells and in vivo animal models. Importantly, human diseases and disorders mediated by these proteins can be studied using these compounds to perhaps initiate drug discovery efforts to develop novel therapeutic agents.
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Affiliation(s)
- Hussein N. Rubaiy
- Centre for Atherothrombosis and Metabolic Disease, Hull York Medical SchoolUniversity of HullHullUK
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15
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Inoue M, Harada K, Matsui M, Matsuoka H. Differences among muscarinic agonists in M 1 receptor-mediated nonselective cation channel activation and TASK1 channel inhibition in adrenal medullary cells. Eur J Pharmacol 2019; 843:104-112. [PMID: 30452911 DOI: 10.1016/j.ejphar.2018.11.021] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Revised: 11/15/2018] [Accepted: 11/15/2018] [Indexed: 10/27/2022]
Abstract
Muscarinic receptor stimulation induces depolarizing inward currents and catecholamine secretion in adrenal medullary (AM) cells from various mammals. In guinea-pig AM cells muscarine and oxotremorine at concentrations ≤ 1 μM produce activation of nonselective cation channels with a similar potency and efficacy, whereas muscarine at higher concentrations produces not only nonselective cation channel activation, but also TASK1 channel inhibition. In rat AM cells, the muscarinic M1 receptor is involved in TASK1 channel inhibition in response to muscarinic agonists, and the efficacy of oxotremorine is half that of muscarine. These pharmacological findings might indicate that different muscarinic receptor subtypes are responsible for the regulation of nonselective cation and TASK1 channel activities. The present study aimed to determine the muscarinic receptor subtypes involved in nonselective cation channel activation in guinea-pig and mouse AM cells. The inward current evoked by 1 μM muscarine was completely suppressed by 100 μM quinine, whereas 30 μM muscarine-induced inward currents were comprised of quinine-sensitive and -insensitive components. The electrophysiological and pharmacological properties of the muscarine-induced currents indicated that the quinine-sensitive and insensitive components are due to nonselective cation channel activation and TASK1 channel inhibition, respectively. Muscarine at 30 μM failed to induce any current in AM cells treated with muscarinic toxin 7 or genetically deleted of the M1 receptor. The KD value of VU0255035 against the muscarinic receptor mediating nonselective cation channel activation was 17.5 nM. These results indicate that the M1 receptor mediates nonselective cation channel activation as well as TASK1 channel inhibition.
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Affiliation(s)
- Masumi Inoue
- Department of Cell and Systems Physiology, University of Occupational and Environmental Health School of Medicine, Kitakyushu 807-8555, Japan.
| | - Keita Harada
- Department of Cell and Systems Physiology, University of Occupational and Environmental Health School of Medicine, Kitakyushu 807-8555, Japan
| | | | - Hidetada Matsuoka
- Department of Cell and Systems Physiology, University of Occupational and Environmental Health School of Medicine, Kitakyushu 807-8555, Japan
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16
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Rubil S, Thiel G. Stimulation of TRPM3 channels increases the transcriptional activation potential of Elk-1 involving cytosolic Ca 2+, extracellular signal-regulated protein kinase, and calcineurin. Eur J Pharmacol 2018; 844:225-230. [PMID: 30552902 DOI: 10.1016/j.ejphar.2018.12.020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Revised: 12/10/2018] [Accepted: 12/11/2018] [Indexed: 12/11/2022]
Abstract
Stimulation of transient receptor potential M3 (TRPM3) channels with the steroid pregnenolone sulfate increases the transcriptional activation potential of Elk-1, a transcription factor that regulates serum response element-mediated transcription. Here, we show that an influx of Ca2+ ions into the cells is essential for the activation of Elk-1 following stimulation of TRPM3. Using genetically encoded Ca2+ buffers, we show that a rise in cytoplasmic Ca2+ is required for the upregulation of the transcriptional activation potential of Elk-1, while buffering of Ca2+ in the nucleus had no inhibitory effect on the transcriptional activity of Elk-1. Pharmacological and genetic experiments showed that extracellular signal-regulated protein kinase (ERK1/2) functions as signal transducer connecting TRPM3 channels with the Elk-1 transcription factor. Accordingly, dephosphorylation of ERK1/2 in the nucleus by MAP kinase phosphatase attenuated TRPM3-mediated Elk-1 activation. Moreover, we show that the Ca2+/calmodulin-dependent protein phosphatase calcineurin is part of a shut-off-device for the signaling cascade connecting TRPM3 channels with the activation of Elk-1. The fact that TRPM3 channel stimulation activates Elk-1 connects TRPM3 with the biological functions of Elk-1, including the regulation of proliferation, differentiation, survival, transcription, and cell migration.
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Affiliation(s)
- Sandra Rubil
- Department of Medical Biochemistry and Molecular Biology Saarland University Medical Faculty, Building 44, D-66421 Homburg, Germany
| | - Gerald Thiel
- Department of Medical Biochemistry and Molecular Biology Saarland University Medical Faculty, Building 44, D-66421 Homburg, Germany.
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17
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Thiel G, Rubil S, Lesch A, Guethlein LA, Rössler OG. Transient receptor potential TRPM3 channels: Pharmacology, signaling, and biological functions. Pharmacol Res 2017; 124:92-99. [DOI: 10.1016/j.phrs.2017.07.014] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Revised: 07/12/2017] [Accepted: 07/12/2017] [Indexed: 12/13/2022]
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18
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Beckmann H, Richter J, Hill K, Urban N, Lemoine H, Schaefer M. A benzothiadiazine derivative and methylprednisolone are novel and selective activators of transient receptor potential canonical 5 (TRPC5) channels. Cell Calcium 2017; 66:10-18. [PMID: 28807145 DOI: 10.1016/j.ceca.2017.05.012] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Revised: 05/19/2017] [Accepted: 05/19/2017] [Indexed: 01/11/2023]
Abstract
The transient receptor potential canonical channel 5 (TRPC5) is a Ca2+-permeable ion channel, which is predominantly expressed in the brain. TRPC5-deficient mice exhibit a reduced innate fear response and impaired motor control. In addition, outgrowth of hippocampal and cerebellar neurons is retarded by TRPC5. However, pharmacological evidence of TRPC5 function on cellular or organismic levels is sparse. Thus, there is still a need for identifying novel and efficient TRPC5 channel modulators. We, therefore, screened compound libraries and identified the glucocorticoid methylprednisolone and N-[3-(adamantan-2-yloxy)propyl]-3-(6-methyl-1,1-dioxo-2H-1λ6,2,4-benzothiadiazin-3-yl)propanamide (BTD) as novel TRPC5 activators. Comparisons with closely related chemical structures from the same libraries indicate important substructures for compound efficacy. Methylprednisolone activates TRPC5 heterologously expressed in HEK293 cells with an EC50 of 12μM, while BTD-induced half-maximal activation is achieved with 5-fold lower concentrations, both in Ca2+ assays (EC50=1.4μM) and in electrophysiological whole cell patch clamp recordings (EC50=1.3 μM). The activation resulting from both compounds is long lasting, reversible and sensitive to clemizole, a recently established TRPC5 inhibitor. No influence of BTD on homotetrameric members of the remaining TRPC family was observed. On the main sensory TRP channels (TRPA1, TRPV1, TRPM3, TRPM8) BTD exerts only minor activity. Furthermore, BTD can activate heteromeric channel complexes consisting of TRPC5 and its closest relatives TRPC1 or TRPC4, suggesting a high selectivity of BTD for channel complexes bearing at least one TRPC5 subunit.
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Affiliation(s)
- Holger Beckmann
- Rudolf-Boehm-Institute of Pharmacology and Toxicology, Leipzig University, Härtelstraße 16-18, 04107 Leipzig, Germany.
| | - Julia Richter
- Rudolf-Boehm-Institute of Pharmacology and Toxicology, Leipzig University, Härtelstraße 16-18, 04107 Leipzig, Germany
| | - Kerstin Hill
- Rudolf-Boehm-Institute of Pharmacology and Toxicology, Leipzig University, Härtelstraße 16-18, 04107 Leipzig, Germany.
| | - Nicole Urban
- Rudolf-Boehm-Institute of Pharmacology and Toxicology, Leipzig University, Härtelstraße 16-18, 04107 Leipzig, Germany.
| | - Horst Lemoine
- Institute for Lasermedicine, Heinrich Heine University Düsseldorf, Universitätsstraße 1, 40225 Düsseldorf, Germany.
| | - Michael Schaefer
- Rudolf-Boehm-Institute of Pharmacology and Toxicology, Leipzig University, Härtelstraße 16-18, 04107 Leipzig, Germany.
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19
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Rubaiy HN, Ludlow MJ, Henrot M, Gaunt HJ, Miteva K, Cheung SY, Tanahashi Y, Hamzah N, Musialowski KE, Blythe NM, Appleby HL, Bailey MA, McKeown L, Taylor R, Foster R, Waldmann H, Nussbaumer P, Christmann M, Bon RS, Muraki K, Beech DJ. Picomolar, selective, and subtype-specific small-molecule inhibition of TRPC1/4/5 channels. J Biol Chem 2017; 292:8158-8173. [PMID: 28325835 PMCID: PMC5437225 DOI: 10.1074/jbc.m116.773556] [Citation(s) in RCA: 70] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Revised: 03/19/2017] [Indexed: 02/02/2023] Open
Abstract
The concentration of free cytosolic Ca2+ and the voltage across the plasma membrane are major determinants of cell function. Ca2+-permeable non-selective cationic channels are known to regulate these parameters, but understanding of these channels remains inadequate. Here we focus on transient receptor potential canonical 4 and 5 proteins (TRPC4 and TRPC5), which assemble as homomers or heteromerize with TRPC1 to form Ca2+-permeable non-selective cationic channels in many mammalian cell types. Multiple roles have been suggested, including in epilepsy, innate fear, pain, and cardiac remodeling, but limitations in tools to probe these channels have restricted progress. A key question is whether we can overcome these limitations and develop tools that are high-quality, reliable, easy to use, and readily accessible for all investigators. Here, through chemical synthesis and studies of native and overexpressed channels by Ca2+ and patch-clamp assays, we describe compound 31, a remarkable small-molecule inhibitor of TRPC1/4/5 channels. Its potency ranged from 9 to 1300 pm, depending on the TRPC1/4/5 subtype and activation mechanism. Other channel types investigated were unaffected, including TRPC3, TRPC6, TRPV1, TRPV4, TRPA1, TRPM2, TRPM8, and store-operated Ca2+ entry mediated by Orai1. These findings suggest identification of an important experimental tool compound, which has much higher potency for inhibiting TRPC1/4/5 channels than previously reported agents, impressive specificity, and graded subtype selectivity within the TRPC1/4/5 channel family. The compound should greatly facilitate future studies of these ion channels. We suggest naming this TRPC1/4/5-inhibitory compound Pico145.
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Affiliation(s)
| | | | - Matthias Henrot
- Institute of Chemistry and Biochemistry, Freie Universität Berlin, Takustrasse 3, 14195 Berlin, Germany
| | | | | | | | - Yasuyuki Tanahashi
- Schools of Medicine; Faculty of Life Sciences, Kyoto Sangyo University, Kyoto 603-8555, Japan
| | | | | | | | | | | | | | - Roger Taylor
- Chemistry, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Richard Foster
- Chemistry, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Herbert Waldmann
- Max-Planck-Institut für Molekulare Physiologie, Otto-Hahn-Strasse 11, 44227 Dortmund, Germany
| | - Peter Nussbaumer
- Lead Discovery Center GmbH, Otto-Hahn-Strasse 15, D-44227 Dortmund, Germany
| | - Mathias Christmann
- Institute of Chemistry and Biochemistry, Freie Universität Berlin, Takustrasse 3, 14195 Berlin, Germany
| | | | - Katsuhiko Muraki
- School of Pharmacy, Aichi-Gakuin University, 1-100 Kusumoto, Chikusa, Nagoya 464-8650, Japan.
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20
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Tykocki NR, Boerman EM, Jackson WF. Smooth Muscle Ion Channels and Regulation of Vascular Tone in Resistance Arteries and Arterioles. Compr Physiol 2017; 7:485-581. [PMID: 28333380 DOI: 10.1002/cphy.c160011] [Citation(s) in RCA: 222] [Impact Index Per Article: 31.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Vascular tone of resistance arteries and arterioles determines peripheral vascular resistance, contributing to the regulation of blood pressure and blood flow to, and within the body's tissues and organs. Ion channels in the plasma membrane and endoplasmic reticulum of vascular smooth muscle cells (SMCs) in these blood vessels importantly contribute to the regulation of intracellular Ca2+ concentration, the primary determinant of SMC contractile activity and vascular tone. Ion channels provide the main source of activator Ca2+ that determines vascular tone, and strongly contribute to setting and regulating membrane potential, which, in turn, regulates the open-state-probability of voltage gated Ca2+ channels (VGCCs), the primary source of Ca2+ in resistance artery and arteriolar SMCs. Ion channel function is also modulated by vasoconstrictors and vasodilators, contributing to all aspects of the regulation of vascular tone. This review will focus on the physiology of VGCCs, voltage-gated K+ (KV) channels, large-conductance Ca2+-activated K+ (BKCa) channels, strong-inward-rectifier K+ (KIR) channels, ATP-sensitive K+ (KATP) channels, ryanodine receptors (RyRs), inositol 1,4,5-trisphosphate receptors (IP3Rs), and a variety of transient receptor potential (TRP) channels that contribute to pressure-induced myogenic tone in resistance arteries and arterioles, the modulation of the function of these ion channels by vasoconstrictors and vasodilators, their role in the functional regulation of tissue blood flow and their dysfunction in diseases such as hypertension, obesity, and diabetes. © 2017 American Physiological Society. Compr Physiol 7:485-581, 2017.
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Affiliation(s)
- Nathan R Tykocki
- Department of Pharmacology, University of Vermont, Burlington, Vermont, USA
| | - Erika M Boerman
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, Missouri, USA
| | - William F Jackson
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan, USA
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21
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Gaunt HJ, Vasudev NS, Beech DJ. Transient receptor potential canonical 4 and 5 proteins as targets in cancer therapeutics. EUROPEAN BIOPHYSICS JOURNAL: EBJ 2016; 45:611-620. [PMID: 27289383 PMCID: PMC5045487 DOI: 10.1007/s00249-016-1142-1] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/29/2015] [Revised: 05/12/2016] [Accepted: 05/16/2016] [Indexed: 12/05/2022]
Abstract
Novel approaches towards cancer therapy are urgently needed. One approach might be to target ion channels mediating Ca2+ entry because of the critical roles played by Ca2+ in many cell types, including cancer cells. There are several types of these ion channels, but here we address those formed by assembly of transient receptor potential canonical (TRPC) proteins, particularly those which involve two closely related members of the family: TRPC4 and TRPC5. We focus on these proteins because recent studies point to roles in important aspects of cancer: drug resistance, transmission of drug resistance through extracellular vesicles, tumour vascularisation, and evoked cancer cell death by the TRPC4/5 channel activator (−)-englerin A. We conclude that further research is both justified and necessary before these proteins can be considered as strong targets for anti-cancer cell drug discovery programmes. It is nevertheless already apparent that inhibitors of the channels would be unlikely to cause significant adverse effects, but, rather, have other effects which may be beneficial in the context of cancer and chemotherapy, potentially including suppression of innate fear, visceral pain and pathological cardiac remodelling.
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Affiliation(s)
- Hannah J Gaunt
- School of Medicine, University of Leeds, LIGHT Building, Clarendon Way, Leeds, LS2 9JT, UK.
| | - Naveen S Vasudev
- School of Medicine, University of Leeds, LIGHT Building, Clarendon Way, Leeds, LS2 9JT, UK
| | - David J Beech
- School of Medicine, University of Leeds, LIGHT Building, Clarendon Way, Leeds, LS2 9JT, UK.
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22
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Suzuki H, Sasaki E, Nakagawa A, Muraki Y, Hatano N, Muraki K. Diclofenac, a nonsteroidal anti-inflammatory drug, is an antagonist of human TRPM3 isoforms. Pharmacol Res Perspect 2016; 4:e00232. [PMID: 27433342 PMCID: PMC4876142 DOI: 10.1002/prp2.232] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Revised: 03/04/2016] [Accepted: 03/07/2016] [Indexed: 11/15/2022] Open
Abstract
The effects of diclofenac (Dic), an acetic acid derivative-type nonsteroidal anti-inflammatory drug, were examined on the function of transient receptor potential (TRP) melastatin (TRPM) 3 (TRPM3) in human embryonic kidney 293 cell-line (HEK293) cells with recombinant human TRPM3 isoforms (TRPM31325, TRPM3-3, TRPM3-9, and TRPM3-S) and in a neuroblastoma cell line human neuroblastoma IMR-32 cells (IMR-32 cells) derived from human peripheral neurons. TRPM3 responses evoked by pregnenolone sulfate (PregS) were effectively inhibited by Dic in a concentration-dependent manner in Ca(2+) measurement and electrophysiological assays. The apparent IC 50 for PregS-induced Ca(2+) response of TRPM31325, TRPM3-3, and TRPM3-9 was calculated to be 18.8, 42.5, and 7.1 μmol/L, respectively. The TRPM3-dependent Ca(2+) responses evoked by nifedipine, another TRPM3 agonist, were also significantly inhibited by Dic. In contrast, aceclofenac, an acetoxymethyl analog of Dic, had no effects on PregS-induced TRPM3 responses. Constitutive channel activity of TRPM3-S without TRPM3 agonists was substantially inhibited by Dic, ruling out the possibility of interaction of Dic against TRPM3 agonists to the channel binding sites. Moreover, Dic reversibly inhibited TRPM3 single-channel activity recorded in excised outside-out patches without affecting the channel conductance. In differentiated neuronal IMR-32 cells with endogenous TRPM3, Dic inhibited PregS-evoked Ca(2+) responses with an apparent IC 50 of 17.1 μmol/L. Taken together, our findings demonstrate that Dic inhibits human TRPM3 without interacting with the channel pore.
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Affiliation(s)
- Hiroka Suzuki
- Laboratory of Cellular PharmacologySchool of PharmacyAichi‐Gakuin University1‐100 KusumotoChikusa, Nagoya464‐8650Japan
| | - Eiji Sasaki
- Laboratory of Cellular PharmacologySchool of PharmacyAichi‐Gakuin University1‐100 KusumotoChikusa, Nagoya464‐8650Japan
| | - Ayumi Nakagawa
- Laboratory of Cellular PharmacologySchool of PharmacyAichi‐Gakuin University1‐100 KusumotoChikusa, Nagoya464‐8650Japan
| | - Yukiko Muraki
- Laboratory of Cellular PharmacologySchool of PharmacyAichi‐Gakuin University1‐100 KusumotoChikusa, Nagoya464‐8650Japan
| | - Noriyuki Hatano
- Laboratory of Cellular PharmacologySchool of PharmacyAichi‐Gakuin University1‐100 KusumotoChikusa, Nagoya464‐8650Japan
| | - Katsuhiko Muraki
- Laboratory of Cellular PharmacologySchool of PharmacyAichi‐Gakuin University1‐100 KusumotoChikusa, Nagoya464‐8650Japan
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23
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Straub I, Mohr F, Stab J, Konrad M, Philipp SE, Oberwinkler J, Schaefer M. Citrus fruit and fabacea secondary metabolites potently and selectively block TRPM3. Br J Pharmacol 2015. [PMID: 23190005 DOI: 10.1111/bph.12076] [Citation(s) in RCA: 72] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
BACKGROUND AND PURPOSE The melastatin-related transient receptor potential TRPM3 is a calcium-permeable nonselective cation channel that can be activated by the neurosteroid pregnenolone sulphate (PregS) and heat. TRPM3-deficient mice show an impaired perception of noxious heat. Hence, drugs inhibiting TRPM3 possibly get in focus of analgesic therapy. EXPERIMENTAL APPROACH Fluorometric methods were used to identify novel TRPM3-blocking compounds and to characterize their potency and selectivity to block TRPM3 but not other sensory TRP channels. Biophysical properties of the block were assessed using electrophysiological methods. Single cell calcium measurements confirmed the block of endogenously expressed TRPM3 channels in rat and mouse dorsal root ganglion (DRG) neurones. KEY RESULTS By screening a compound library, we identified three natural compounds as potent blockers of TRPM3. Naringenin and hesperetin belong to the citrus fruit flavanones, and ononetin is a deoxybenzoin. Eriodictyol, a metabolite of naringenin and hesperetin, was still biologically active as a TRPM3 blocker. The compounds exhibited a marked specificity for recombinant TRPM3 and blocked PregS-induced [Ca(2+)]i signals in freshly isolated DRG neurones. CONCLUSION AND IMPLICATIONS The data indicate that citrus fruit flavonoids are potent and selective blockers of TRPM3. Their potencies ranged from upper nanomolar to lower micromolar concentrations. Since physiological functions of TRPM3 channels are still poorly defined, the development and validation of potent and selective blockers is expected to contribute to clarifying the role of TRPM3 in vivo. Considering the involvement of TRPM3 in nociception, TRPM3 blockers may represent a novel concept for analgesic treatment.
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Affiliation(s)
- I Straub
- Rudolf-Boehm-Institut für Pharmakologie und Toxikologie, Universität Leipzig, Leipzig, Germany
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Held K, Voets T, Vriens J. TRPM3 in temperature sensing and beyond. Temperature (Austin) 2015; 2:201-13. [PMID: 27227024 PMCID: PMC4844244 DOI: 10.4161/23328940.2014.988524] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2014] [Revised: 11/06/2014] [Accepted: 11/12/2014] [Indexed: 12/13/2022] Open
Abstract
TRPM3, also known as melastatin 2 (MLSN2), LTRPC3 (long TRPC3) and KIAA1616, is a member of the TRPM subfamily of transient receptor potential (TRP) ion channels. The channel was originally identified as a volume-regulated ion channel that can be activated upon reduction of the extracellular osmolality. Later, the channel was proposed to be involved in the modulation of insulin release in pancreatic islets. However, new evidence has uncovered a role of TRPM3 as a thermosensitive nociceptor channel implicated in the detection of noxious heat. The channel is functionally expressed in a subset of neurons of the somatosensory system and can be activated by heat. The purpose of the present review is to summarize existing knowledge of the expression, biophysics and pharmacology of TRPM3 and to serve as a guide for future studies aimed at improving the understanding of the mechanism of thermosensation and proposed physiological functions of TRPM3.
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Key Words
- Clt, Clotrimazole
- DHEA, Dehydroepiandrosterone
- DRG, Dorsal root ganglion
- DeSPH, D-erythro-sphingosine
- PCR, Polymerase chain reaction
- PPAR-γ, Peroxisome proliferator-activator receptor - γ
- PS, Pregnenolone sulfate
- Q10, 10-degree temperature coefficient
- RT, Room temperature
- TG, Trigeminal ganglion
- TRP channel
- TRP, Transient receptor potential
- TRPM, Transient receptor potential melastatin
- TRPM3
- TRPV, Transient receptor potential vanilloid
- nociceptor
- sensory system
- temperature sensing
- ΔG, Gibbs free energy
- ΔH, Enthalpy
- ΔS, Entropy
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Affiliation(s)
- Katharina Held
- Laboratory of Experimental Gynecology; KU Leuven; Leuven, Belgium; Laboratory of Ion Channel Research and TRP Research Platform Leuven (TRPLe); KU Leuven; Leuven, Belgium
| | - Thomas Voets
- Laboratory of Ion Channel Research and TRP Research Platform Leuven (TRPLe); KU Leuven ; Leuven, Belgium
| | - Joris Vriens
- Laboratory of Experimental Gynecology; KU Leuven ; Leuven, Belgium
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Lesch A, Rubil S, Thiel G. Activation and inhibition of transient receptor potential TRPM3-induced gene transcription. Br J Pharmacol 2014; 171:2645-58. [PMID: 24895737 DOI: 10.1111/bph.12524] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
BACKGROUND AND PURPOSE Transient receptor potential-3 (TRPM3) channels function as Ca2+ permeable cation channels. While the natural ligands for these channels are still unknown, several compounds have been described that either activate or inhibit TRPM3 channel activity. experimental approach: We assessed TRPM3-mediated gene transcription, which relies on the induction of intracellular signalling to the nucleus following activation of TRPM3 channels. Activator protein-1 (AP-1) and Egr-1-responsive reporter genes were integrated into the chromatin of the cells. This strategy enabled us to analyse gene transcription of the AP-1 and Egr-1-responsive reporter genes that were packed into an ordered chromatin structure. KEY RESULTS The neurosteroid pregnenolone sulfate strikingly up-regulated AP-1 and Egr-1 transcriptional activity, while nifedipine and D-erythro-sphingosine, also putative activators of TRPM3 channels, exhibited either no or TRPM3-independent effects on gene transcription. In addition, pregnenolone sulfate robustly enhanced the transcriptional activation potential of the ternary complex factor Elk-1. Pregnenolone sulfate-induced activation of gene transcription was blocked by treatment with mefenamic acid and, to a lesser extent, by the polyphenol naringenin. In contrast, progesterone, pregnenolone and rosiglitazone reduced AP-1 activity in the cells, but had no inhibitory effect on Egr-1 activity in pregnenolone sulfate-stimulated cells. CONCLUSION AND IMPLICATIONS Pregnenolone sulfate is a powerful activator of TRPM3-mediated gene transcription, while transcription is completely inhibited by mefenamic acid in cells expressing activated TRPM3 channels. Both compounds are valuable tools for further investigating the biological functions of TRPM3 channels.
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Richter JM, Schaefer M, Hill K. Riluzole activates TRPC5 channels independently of PLC activity. Br J Pharmacol 2014; 171:158-70. [PMID: 24117252 DOI: 10.1111/bph.12436] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2013] [Revised: 09/05/2013] [Accepted: 09/15/2013] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND AND PURPOSE The transient receptor potential channel C5 (TRPC5) is a Ca(2+)-permeable cation channel, which is predominantly expressed in the brain. TRPC5 is activated in a PLC-dependent manner by, as yet, unidentified endogenous messengers. Recently, modulators of TRPC5, like Ca(2+), pH and phospholipids, have been identified. However, the role of TRPC5 in vivo is only poorly understood. Novel specific modulators of TRPC5 might help to elucidate its function. EXPERIMENTAL APPROACH Novel modulators of TRPC5 were identified in a compound screening of approved drugs and natural compounds. The potency and selectivity of TRPC5-activating compounds were determined by fluorometric calcium imaging. The biophysical properties of channel activation by these compounds were analysed using electrophysiological measurements. KEY RESULTS Riluzole was identified as a novel activator of TRPC5 (EC₅₀ 9.2 ± 0.5 μM) and its mechanism of action was shown to be independent of G protein signalling and PLC activity. Riluzole-induced TRPC5 currents were potentiated by La(3+) and, utilizing TRPC5 mutants that lack La(3+) binding sites, it was confirmed that riluzole and La(3+) activate TRPC5 by different mechanisms. Recordings of excised inside-out patches revealed a relatively direct effect of riluzole on TRPC5. CONCLUSIONS AND IMPLICATIONS Riluzole can activate TRPC5 heterologously expressed in HEK293 cells as well as those endogenously expressed in the U-87 glioblastoma cell line. Riluzole does not activate any other member of the TRPC family and could, therefore, despite its action on other ion channels, be a useful pharmacological tool for identifying TRPC5-specific currents in immortalized cell lines or in acutely isolated primary cells.
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Affiliation(s)
- Julia M Richter
- Rudolf-Boehm-Institute of Pharmacology and Toxicology, University of Leipzig, Leipzig, Germany
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Bon RS, Beech DJ. In pursuit of small molecule chemistry for calcium-permeable non-selective TRPC channels -- mirage or pot of gold? Br J Pharmacol 2014; 170:459-74. [PMID: 23763262 DOI: 10.1111/bph.12274] [Citation(s) in RCA: 76] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2013] [Revised: 04/29/2013] [Accepted: 05/09/2013] [Indexed: 12/21/2022] Open
Abstract
The primary purpose of this review is to address the progress towards small molecule modulators of human Transient Receptor Potential Canonical proteins (TRPC1, TRPC3, TRPC4, TRPC5, TRPC6 and TRPC7). These proteins generate channels for calcium and sodium ion entry. They are relevant to many mammalian cell types including acinar gland cells, adipocytes, astrocytes, cardiac myocytes, cochlea hair cells, endothelial cells, epithelial cells, fibroblasts, hepatocytes, keratinocytes, leukocytes, mast cells, mesangial cells, neurones, osteoblasts, osteoclasts, platelets, podocytes, smooth muscle cells, skeletal muscle and tumour cells. There are broad-ranging positive roles of the channels in cell adhesion, migration, proliferation, survival and turning, vascular permeability, hypertrophy, wound-healing, hypo-adiponectinaemia, angiogenesis, neointimal hyperplasia, oedema, thrombosis, muscle endurance, lung hyper-responsiveness, glomerular filtration, gastrointestinal motility, pancreatitis, seizure, innate fear, motor coordination, saliva secretion, mast cell degranulation, cancer cell drug resistance, survival after myocardial infarction, efferocytosis, hypo-matrix metalloproteinase, vasoconstriction and vasodilatation. Known small molecule stimulators of the channels include hyperforin, genistein and rosiglitazone, but there is more progress with inhibitors, some of which have promising potency and selectivity. The inhibitors include 2-aminoethoxydiphenyl borate, 2-aminoquinolines, 2-aminothiazoles, fatty acids, isothiourea derivatives, naphthalene sulfonamides, N-phenylanthranilic acids, phenylethylimidazoles, piperazine/piperidine analogues, polyphenols, pyrazoles and steroids. A few of these agents are starting to be useful as tools for determining the physiological and pathophysiological functions of TRPC channels. We suggest that the pursuit of small molecule modulators for TRPC channels is important but that it requires substantial additional effort and investment before we can reap the rewards of highly potent and selective pharmacological modulators.
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Affiliation(s)
- Robin S Bon
- School of Chemistry, University of Leeds, Leeds, UK
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Liquiritigenin alleviates mechanical and cold hyperalgesia in a rat neuropathic pain model. Sci Rep 2014; 4:5676. [PMID: 25022218 PMCID: PMC4097342 DOI: 10.1038/srep05676] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2014] [Accepted: 06/03/2014] [Indexed: 02/07/2023] Open
Abstract
This study assessed the potential antinociceptive effects of liquiritigenin, a plant-derived compound with transient receptor potential melastatin 3 blocking activity in a rat model of persistent neuropathic pain. Chronic constriction injury (CCI) to the sciatic nerve was induced in male Sprague-Dawley rats to model human peripheral neuropathic pain. Liquiritigenin (1, 3, or 9 mg/kg) was administered intraperitoneally to examine the effects on mechanical, thermal, and cold hyperalgesia using the von Frey test, plantar test, and cold plate test, respectively. A rotarod test was also conducted to examine motor function. Liquiritigenin dose dependently alleviated mechanical, thermal and cold hyperalgesia. In addition, daily repeated treatment with liquiritigenin did not demonstrate significant antinociceptive tolerance in the measures of hyperalgesia. Within the doses studied, liquiritigenin did not significantly affect motor performance. These results suggest that liquiritigenin may be potentially useful novel treatments for neuropathic pain.
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Kaneko Y, Szallasi A. Transient receptor potential (TRP) channels: a clinical perspective. Br J Pharmacol 2014; 171:2474-507. [PMID: 24102319 PMCID: PMC4008995 DOI: 10.1111/bph.12414] [Citation(s) in RCA: 284] [Impact Index Per Article: 28.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2013] [Revised: 08/28/2013] [Accepted: 08/31/2013] [Indexed: 12/14/2022] Open
Abstract
Transient receptor potential (TRP) channels are important mediators of sensory signals with marked effects on cellular functions and signalling pathways. Indeed, mutations in genes encoding TRP channels are the cause of several inherited diseases in humans (the so-called 'TRP channelopathies') that affect the cardiovascular, renal, skeletal and nervous systems. TRP channels are also promising targets for drug discovery. The initial focus of research was on TRP channels that are expressed on nociceptive neurons. Indeed, a number of potent, small-molecule TRPV1, TRPV3 and TRPA1 antagonists have already entered clinical trials as novel analgesic agents. There has been a recent upsurge in the amount of work that expands TRP channel drug discovery efforts into new disease areas such as asthma, cancer, anxiety, cardiac hypertrophy, as well as obesity and metabolic disorders. A better understanding of TRP channel functions in health and disease should lead to the discovery of first-in-class drugs for these intractable diseases. With this review, we hope to capture the current state of this rapidly expanding and changing field.
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Affiliation(s)
- Yosuke Kaneko
- Discovery Research Alliance, Ono Pharmaceutical Co. LtdOsaka, Japan
| | - Arpad Szallasi
- Department of Pathology and Laboratory Medicine, Monmouth Medical CenterLong Branch, NJ, USA
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30
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Abstract
Drug-like compounds that exert biological activity towards TRP channels are either being used as cell biological tools or further developed into pharmacological lead structures aiming at therapeutic use in diseased states. Although drug-likeliness is not easy to predict, common rules include a relatively low molecular weight, physicochemical constraints, and the absence of known reactive or otherwise toxic groups. Small molecules that exert a biological activity to block, activate, or modulate TRP channels are intensely sought. Such tool compounds may be useful to assign native currents to a certain TRP channel and to validate the channel as a candidate target for future pharmacological intervention. Depending on the TRP channel isotype, these activities have reached different levels, with only few TRP channels modulators already being clinically tested in humans, whereas other compounds only underwent a preliminary validation. For some TRP channels, reliable low molecular weight inhibitors are not yet available. Hence, further efforts need to be undertaken in order to explore the physiological impact and possible therapeutic potential of TRP channel targeting with drug-like compounds.
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Affiliation(s)
- Michael Schaefer
- Rudolf-Boehm-Institut für Pharmakologie und Toxikologie, Härtelstraße 16-18, 04107, Leipzig, Germany,
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31
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Abstract
Like most other members of the TRP family, the Trpm3 gene encodes proteins that form cation-permeable ion channels on the plasma membrane. However, TRPM3 proteins have several unique features that set them apart from the other members of this diverse family. The Trpm3 gene encodes for a surprisingly large number of isoforms generated mainly by alternative splicing. Only for two of the (at least) eight sites at which sequence diversity is generated the functional consequences have been elucidated, one leading to nonfunctional channels, the other one profoundly affecting the ionic selectivity. In the Trpm3 gene an intronic microRNA (miR-204) is co-transcribed with Trpm3. By regulating the expression of a multitude of genes, miR-204 increases the functional complexity of the Trpm3 locus. Over the past years, important progress has been made in discovering pharmacological tools to manipulate TRPM3 channel activity. These substances have facilitated the identification of endogenously expressed functional TRPM3 channels in nociceptive neurons, pancreatic beta cells, and vascular smooth muscle cells, among others. TRPM3 channels, which themselves are temperature sensitive, thus have been implicated in sensing noxious heat, in modulating insulin release, and in secretion of inflammatory cytokines. However, in many tissues where TRPM3 proteins are known to be expressed, no functional role has been identified for these channels so far. Because of the availability of adequate pharmacological and genetic tools, it is expected that future investigations on TRPM3 channels will unravel important new aspects and functions of these channels.
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Affiliation(s)
- Johannes Oberwinkler
- Institut für Physiologie und Pathophysiologie, Philipps-Universität Marburg, 35037, Marburg, Germany,
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32
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Stoelzle-Feix S. State-of-the-art automated patch clamp: heat activation, action potentials, and high throughput in ion channel screening. Methods Mol Biol 2014; 1183:65-80. [PMID: 25023302 DOI: 10.1007/978-1-4939-1096-0_4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
A successful robotic approach of the patch clamp technique is based on planar patch clamp chips where a glass pipette, as used in conventional patch clamping, is replaced by a thin planar glass sheet with a small hole in the middle. Automated patch clamp (APC) systems utilizing this chip design offer higher throughput capabilities and ease of use and thus have become common in basic research, drug development, and safety screening. Further development of existing devices and introduction of new systems widen the range of possible experiments and increase throughput. Here, two features with different areas of applications that meet the needs of drug discovery researchers and basic researchers alike are described. The utilized system is a medium throughput APC device capable of recording up to eight cells simultaneously. The temperature control capability and the possibility to perform recordings not only in the voltage clamp but also in the current clamp mode are described in detail. Since eight recordings can be generated in parallel without compromising data quality, reliable and cost-effective and time-effective screening of compounds against ion channels using voltage clamp and current clamp electrophysiology can be performed.
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Alexander SPH, Benson HE, Faccenda E, Pawson AJ, Sharman JL, Catterall WA, Spedding M, Peters JA, Harmar AJ. The Concise Guide to PHARMACOLOGY 2013/14: ion channels. Br J Pharmacol 2013; 170:1607-51. [PMID: 24528239 PMCID: PMC3892289 DOI: 10.1111/bph.12447] [Citation(s) in RCA: 224] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The Concise Guide to PHARMACOLOGY 2013/14 provides concise overviews of the key properties of over 2000 human drug targets with their pharmacology, plus links to an open access knowledgebase of drug targets and their ligands (www.guidetopharmacology.org), which provides more detailed views of target and ligand properties. The full contents can be found at http://onlinelibrary.wiley.com/doi/10.1111/bph.12444/full. Ion channels are one of the seven major pharmacological targets into which the Guide is divided, with the others being G protein-coupled receptors, ligand-gated ion channels, catalytic receptors, nuclear hormone receptors, transporters and enzymes. These are presented with nomenclature guidance and summary information on the best available pharmacological tools, alongside key references and suggestions for further reading. A new landscape format has easy to use tables comparing related targets. It is a condensed version of material contemporary to late 2013, which is presented in greater detail and constantly updated on the website www.guidetopharmacology.org, superseding data presented in previous Guides to Receptors and Channels. It is produced in conjunction with NC-IUPHAR and provides the official IUPHAR classification and nomenclature for human drug targets, where appropriate. It consolidates information previously curated and displayed separately in IUPHAR-DB and the Guide to Receptors and Channels, providing a permanent, citable, point-in-time record that will survive database updates.
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Affiliation(s)
- Stephen PH Alexander
- School of Life Sciences, University of Nottingham Medical SchoolNottingham, NG7 2UH, UK
- *
Author for correspondence;
| | - Helen E Benson
- The University/BHF Centre for Cardiovascular Science, University of EdinburghEdinburgh, EH16 4TJ, UK
| | - Elena Faccenda
- The University/BHF Centre for Cardiovascular Science, University of EdinburghEdinburgh, EH16 4TJ, UK
| | - Adam J Pawson
- The University/BHF Centre for Cardiovascular Science, University of EdinburghEdinburgh, EH16 4TJ, UK
| | - Joanna L Sharman
- The University/BHF Centre for Cardiovascular Science, University of EdinburghEdinburgh, EH16 4TJ, UK
| | - William A Catterall
- University of Washington, School of Medicine, Department of PharmacologyBox 357280, Seattle, WA 98195-7280, USA
| | | | - John A Peters
- Neuroscience Division, Medical Education Institute, Ninewells Hospital and Medical School, University of DundeeDundee, DD1 9SY, UK
| | - Anthony J Harmar
- The University/BHF Centre for Cardiovascular Science, University of EdinburghEdinburgh, EH16 4TJ, UK
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Straub I, Krügel U, Mohr F, Teichert J, Rizun O, Konrad M, Oberwinkler J, Schaefer M. Flavanones that selectively inhibit TRPM3 attenuate thermal nociception in vivo. Mol Pharmacol 2013; 84:736-50. [PMID: 24006495 DOI: 10.1124/mol.113.086843] [Citation(s) in RCA: 91] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Transient receptor potential melastatin 3 (TRPM3) is a calcium-permeable nonselective cation channel that is expressed in a subset of dorsal root (DRG) and trigeminal ganglia sensory neurons. TRPM3 can be activated by the neurosteroid pregnenolone sulfate (PregS) and heat. TRPM3⁻/⁻ mice display an impaired sensation of noxious heat and thermal hyperalgesia. We have previously shown that TRPM3 is blocked by the citrus fruit flavanones hesperetin, naringenin, and eriodictyol as well as by ononetin, a deoxybenzoin from Ononis spinosa. To further improve the tolerability, potency, and selectivity of TRPM3 blockers, we conducted a hit optimization procedure by rescreening a focused library that was composed of chemically related compounds. Within newly identified TRPM3 blockers, isosakuranetin and liquiritigenin displayed favorable properties with respect to their inhibitory potency and a selective mode of action. Isosakuranetin, a flavanone whose glycoside is contained in blood oranges and grapefruits, displayed an IC₅₀ of 50 nM and is to our knowledge the most potent inhibitor of TRPM3 identified so far. Both compounds exhibited a marked specificity for TRPM3 compared with other sensory TRP channels, and blocked PregS-induced intracellular free Ca²⁺ concentration signals and ionic currents in freshly isolated DRG neurons. Furthermore, isosakuranetin and previously identified hesperetin significantly reduced the sensitivity of mice to noxious heat and PregS-induced chemical pain. Because the physiologic functions of TRPM3 channels are still poorly defined, the development and validation of potent and selective blockers is expected to contribute to clarifying the role of TRPM3 in vivo.
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Affiliation(s)
- Isabelle Straub
- Rudolf-Boehm-Institut für Pharmakologie und Toxikologie, Universität Leipzig, Leipzig, Germany (I.S., U.K., J.T., M.S.); and Institut für Physiologie und Pathophysiologie, Philipps-Universität Marburg, Marburg, Germany (F.M., O.R., M.K., J.O.)
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Abstract
Transient receptor potential melastatin 3 (TRPM3) channels are non-selective cation channels that are expressed in insulinoma cells and pancreatic β-cells. Stimulation of TRPM3 with the neurosteroid pregnenolone sulfate induces an intracellular signaling cascade, involving a rise in intracellular Ca(2)(+) concentration, activation of the protein kinases Raf and ERK, and a change in the gene expression pattern of the cells. In particular, biosynthesis of insulin is altered following activation of TRPM3 by pregnenolone sulfate. Moreover, a direct effect of TRPM3 stimulation on insulin secretion has been reported. The fact that stimulation of TRPM3 induces a signaling cascade that is very similar to the signaling cascade induced by glucose in β-cells suggests that TRPM3 may influence main functions of pancreatic β-cells. The view that TRPM3 represents an ionotropic steroid receptor of pancreatic β-cells linking insulin release with steroid hormone signaling is discussed.
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Affiliation(s)
- Gerald Thiel
- Department of Medical Biochemistry and Molecular Biology, University of Saarland Medical Center, Building 44, D-66421 Homburg, Germany.
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Peroxisome proliferator-activated receptor-gamma agonist rosiglitazone attenuates inflammatory pain through the induction of heme oxygenase-1 in macrophages. Pain 2013; 154:1402-12. [PMID: 23707273 DOI: 10.1016/j.pain.2013.04.039] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2012] [Revised: 04/10/2013] [Accepted: 04/17/2013] [Indexed: 11/23/2022]
Abstract
Macrophage infiltration to inflammatory sites promotes tissue repair and may be involved in pain hypersensitivity. Peroxisome proliferator-activated receptor (PPAR)γ signaling is known to regulate polarity of macrophages, which are often referred to as proinflammatory (M1) and antiinflammatory (M2) macrophages. We recently showed that the PPARγ agonist rosiglitazone ameliorated the development of postincisional hyperalgesia by increasing the influx of M2 macrophages to inflamed sites. It has been suggested that heme oxygenase (HO)-1, upregulated by PPARγ signaling, promotes differentiation of macrophages to M2 phenotype. In this study, we investigated how rosiglitazone alters pain hypersensitivity by a PPARγHO-1-dependent mechanism during the course of inflammation induced by complete Freund's adjuvant. Local administration of rosiglitazone alleviated mechanical hyperalgesia, with increased gene induction of HO-1. Phenotype switching of infiltrated macrophages to M2 by rosiglitazone was reversed by an HO-1 inhibitor, tin protoporphyrin, at the inflamed sites. Direct stimulation of peritoneal macrophages with rosiglitazone also increased HO-1 induction in the presence of lipopolysaccharide/interferon-γ. Moreover, rosiglitazone increased gene induction of endogenous opioid proenkephalin, both at inflamed sites and in isolated macrophages. Administration of naloxone blocked the analgesic effects of rosiglitazone. We speculate that rosiglitazone alleviated the development of inflammatory pain, possibly through regulating the M1/M2 balance at the inflamed site by a PPARγ/HO-1-dependent mechanism. PPARγ signaling in macrophages may be a potential therapeutic target for the treatment of acute pain development.
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Abstract
Ion channels are integral membrane proteins that regulate the flow of ions across the plasma membrane and the membranes of intracellular organelles of both excitable and non-excitable cells. Ion channels are vital to a wide variety of biological processes and are prominent components of the nervous system and cardiovascular system, as well as controlling many metabolic functions. Furthermore, ion channels are known to be involved in many disease states and as such have become popular therapeutic targets. For many years now manual patch-clamping has been regarded as one of the best approaches for assaying ion channel function, through direct measurement of ion flow across these membrane proteins. Over the last decade there have been many remarkable breakthroughs in the development of technologies enabling the study of ion channels. One of these breakthroughs is the development of automated planar patch-clamp technology. Automated platforms have demonstrated the ability to generate high-quality data with high throughput capabilities, at great efficiency and reliability. Additional features such as simultaneous intracellular and extracellular perfusion of the cell membrane, current clamp operation, fast compound application, an increasing rate of parallelization, and more recently temperature control have been introduced. Furthermore, in addition to the well-established studies of over-expressed ion channel proteins in cell lines, new generations of planar patch-clamp systems have enabled successful studies of native and primary mammalian cells. This technology is becoming increasingly popular and extensively used both within areas of drug discovery as well as academic research. Many platforms have been developed including NPC-16 Patchliner(®) and SyncroPatch(®) 96 (Nanion Technologies GmbH, Munich), CytoPatch™ (Cytocentrics AG, Rostock), PatchXpress(®) 7000A, IonWorks(®) Quattro and IonWorks Barracuda™, (Molecular Devices, LLC); Dynaflow(®) HT (Cellectricon AB, Mölndal), QPatch HT (Sophion A/S, Copenhagen), IonFlux HT (Fluxion Bioscience Inc, USA), which have demonstrated the capability to generate recordings similar in quality to that of conventional patch clamping. Here we describe features of Nanion's NPC-16 Patchliner(®) and processes and protocols suited for this particularly flexible and successful high-throughput automated platform, which is based on planar patch-clamp technology. However, many of the protocols and notes given in this chapter can be applied to other automated patch-clamp platforms, similarly.
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Affiliation(s)
- Carol J Milligan
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, Kenneth Myer Building, Royal Parade, Melbourne, VIC, Australia
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Sukumar P, Sedo A, Li J, Wilson LA, O'Regan D, Lippiat JD, Porter KE, Kearney MT, Ainscough JFX, Beech DJ. Constitutively active TRPC channels of adipocytes confer a mechanism for sensing dietary fatty acids and regulating adiponectin. Circ Res 2012; 111:191-200. [PMID: 22668831 DOI: 10.1161/circresaha.112.270751] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
RATIONALE Calcium entry is pivotal in the heart and blood vessels, but its significance and mechanisms in adipose tissue are largely unknown. An important factor produced by adipocytes is adiponectin, which confers myocardial protection, insulin-sensitization, and antiatherosclerotic effects. OBJECTIVE To investigate the relevance of calcium channels to adipocytes and the production of adiponectin. METHODS AND RESULTS Microarray analysis led to identification of transient receptor potential canonical (TRPC)1 and TRPC5 as channel subunits that are induced when adipocytes mature. Both subunits were found in perivascular fat of patients with atherosclerosis. Intracellular calcium and patch-clamp measurements showed that adipocytes exhibit constitutively active calcium-permeable nonselective cationic channels that depend on TRPC1 and TRPC5. The activity could be enhanced by lanthanum or rosiglitazone, known stimulators of TRPC5 and TRPC5-containing channels. Screening identified lipid modulators of the channels that are relevant to adipose biology. Dietary ω-3 fatty acids (eg, α-linolenic acid) were inhibitory at concentrations that are achieved by ingestion. The adipocyte TRPC1/TRPC5-containing channel was functionally negative for the generation of adiponectin because channel blockade by antibodies, knock-down of TRPC1-TRPC5 in vitro, or conditional disruption of calcium permeability in TRPC5-incorporating channels in vivo increased the generation of adiponectin. The previously recognized capability of α-linolenic acid to stimulate the generation of adiponectin was lost when calcium permeability in the channels was disrupted. CONCLUSIONS The data suggest that TRPC1 and TRPC5 contribute a constitutively active heteromultimeric channel of adipocytes that negatively regulates adiponectin and through which ω-3 fatty acids enhance the anti-inflammatory adipokine, adiponectin.
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Affiliation(s)
- Piruthivi Sukumar
- Multidisciplinary Cardiovascular Research Centre, University of Leeds, UK
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Sgarra L, Addabbo F, Potenza MA, Montagnani M. Determinants of evolving metabolic and cardiovascular benefit/risk profiles of rosiglitazone therapy during the natural history of diabetes: molecular mechanisms in the context of integrated pathophysiology. Am J Physiol Endocrinol Metab 2012; 302:E1171-82. [PMID: 22374753 DOI: 10.1152/ajpendo.00038.2012] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Rosiglitazone is a thiazolidinedione, a synthetic PPARγ receptor agonist with insulin-sensitizing properties that is used as an antidiabetic drug. In addition to improving glycemic control through actions in metabolic target tissues, rosiglitazone has numerous biological actions that impact on cardiovascular homeostasis. Some of these actions are helpful (e.g., improving endothelial function), whereas others are potentially harmful (e.g., promoting fluid retention). Since cardiovascular morbidity and mortality are major endpoints for diabetes, it is essential to understand how the natural history of diabetes alters the net benefits and risks of rosiglitazone therapy. This complex issue is an important determinant of optimal use of rosiglitazone and is critical for understanding cardiovascular safety issues. We give special attention to the effects of rosiglitazone in diabetic patients with stable coronary artery disease and the impact of rosiglitazone actions on atherosclerosis and plaque instability. This provides a rational conceptual framework for predicting evolving benefit/risk profiles that inform optimal use of rosiglitazone in the clinical setting and help explain the results of recent large clinical intervention trials where rosiglitazone had disappointing cardiovascular outcomes. Thus, in this perspective, we describe what is known about the molecular mechanisms of action of rosiglitazone on cardiovascular targets in the context of the evolving pathophysiology of diabetes over its natural history.
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Affiliation(s)
- Luca Sgarra
- Department of Biomedical Sciences and Human Oncology, Medical School, University of Bari, Bari, Italy
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Neri T, Cordazzo C, Carmazzi Y, Petrini S, Balìa C, Stefanelli F, Amoruso A, Brunelleschi S, Breschi MC, Pedrinelli R, Paggiaro P, Celi A. Effects of peroxisome proliferator-activated receptor-γ agonists on the generation of microparticles by monocytes/macrophages. Cardiovasc Res 2012; 94:537-44. [DOI: 10.1093/cvr/cvs125] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Pregnenolone sulphate-independent inhibition of TRPM3 channels by progesterone. Cell Calcium 2011; 51:1-11. [PMID: 22000496 PMCID: PMC3275754 DOI: 10.1016/j.ceca.2011.09.005] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2011] [Revised: 09/12/2011] [Accepted: 09/21/2011] [Indexed: 11/23/2022]
Abstract
Transient Receptor Potential Melastatin 3 (TRPM3) is a widely expressed calcium-permeable non-selective cation channel that is stimulated by high concentrations of nifedipine or by physiological steroids that include pregnenolone sulphate. Here we sought to identify steroids that inhibit TRPM3. Channel activity was studied using calcium-measurement and patch-clamp techniques. Progesterone (0.01–10 μM) suppressed TRPM3 activity evoked by pregnenolone sulphate. Progesterone metabolites and 17β-oestradiol were also inhibitory but the effects were relatively small. Dihydrotestosterone was an inhibitor at concentrations higher than 1 μM. Corticosteroids lacked effect. Overlay assays indicated that pregnenolone sulphate, progesterone and dihydrotestosterone bound to TRPM3. In contrast to dihydrotestosterone, progesterone inhibited nifedipine-evoked TRPM3 activity or activity in the absence of an exogenous activator, suggesting a pregnenolone sulphate-independent mechanism of action. Dihydrotestosterone, like a non-steroid look-alike compound, acted as a competitive antagonist at the pregnenolone sulphate binding site. Progesterone inhibited endogenous TRPM3 in vascular smooth muscle cells. Relevance of TRPM3 or the progesterone effect to ovarian cells, which have been suggested to express TRPM3, was not identified. The data further define a chemical framework for competition with pregnenolone sulphate at TRPM3 and expand knowledge of steroid interactions with TRPM3, suggesting direct steroid binding and pregnenolone sulphate-independent inhibition by progesterone.
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Farooqi AA, Javeed MK, Javed Z, Riaz AM, Mukhtar S, Minhaj S, Abbas S, Bhatti S. TRPM channels: same ballpark, different players, and different rules in immunogenetics. Immunogenetics 2011; 63:773-87. [PMID: 21932052 DOI: 10.1007/s00251-011-0570-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2011] [Accepted: 09/02/2011] [Indexed: 11/29/2022]
Abstract
Transient receptor potential (TRP) channels belong to a large family of cation channels and are the "border guards" predominantly localized to the plasma membrane. Research over the years has considerably and highly developed the knowledge of expression and functional aspects of the TRPM channels. A closer look at the channel dynamics has dismantled undeniable substantiation for multifaceted roles for TRPM channel-mediated extracellular Ca(2+) influx in several physiological and pathophysiological functions. Given the wealth of literature unfolding the multiple roles of TRP channels in physiology in a very extensive range of different mammalian tissues, this review confines itself to the literature describing the multiple roles of TRPM channels in diabetes, smooth muscle cell regulation, immunological responses, and emerging aspects of cancer. We also focus on differential activities of TRPM channels after post-transcriptional and post-translational processing and their exquisite roles at various cellular and molecular levels.
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Affiliation(s)
- Ammad Ahmad Farooqi
- Institute of Molecular Biology and Biotechnology (IMBB), The University of Lahore, Punjab, Pakistan.
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