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Parkia platycephala Lectin (PPL) Inhibits Orofacial Nociception Responses via TRPV1 Modulation. Molecules 2022; 27:molecules27217506. [DOI: 10.3390/molecules27217506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Revised: 10/20/2022] [Accepted: 10/27/2022] [Indexed: 11/06/2022] Open
Abstract
Lectins are a heterogeneous group of proteins that reversibly bind to simple sugars or complex carbohydrates. The plant lectin purified from the seed of Parkia platycephala (PPL) was studied. This study aimed to investigate the possible orofacial antinociceptive of PPL lectin in adult zebrafish and rodents. Acute nociception was induced by cinnamaldehyde (0.66 μg/mL), 0.1% acidified saline, glutamate (12.5 µM) or hypertonic saline (5 M NaCl) applied into the upper lip (5.0 µL) of adult wild zebrafish. Zebrafish were pretreated by intraperitoneal injection (20 µL) with vehicle (Control) or PPL (0.025; 0.05 or 0.1 mg/mL) 30 min before induction. The effect of PPL on zebrafish locomotor behaviour was evaluated in the open field test. Naive groups were included in all tests. In one experiment, animals were pre-treated with capsazepine to investigate the mechanism of antinociception. The involvement of central afferent C-fibres was also investigated. In another experiment, rats pre-treated with PPL or saline were submitted to the temporomandibular joint formalin test. Other groups of rats were submitted to infraorbital nerve transection to induce chronic pain, followed by induction of mechanical sensitivity using von Frey. PPL reduced nociceptive behaviour in adult zebrafish, and this is related to the activation of the TRPV1 channels since antinociception was effectively inhibited by capsazepine and by capsaicin-induced desensitization. PPL reduced nociceptive behaviour associated with temporomandibular joint and neuropathic pain. The results confirm the potential pharmacological relevance of PPL as an inhibitor of orofacial nociception in acute and chronic pain.
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Negri S, Faris P, Tullii G, Vismara M, Pellegata AF, Lodola F, Guidetti G, Rosti V, Antognazza MR, Moccia F. Conjugated polymers mediate intracellular Ca 2+ signals in circulating endothelial colony forming cells through the reactive oxygen species-dependent activation of Transient Receptor Potential Vanilloid 1 (TRPV1). Cell Calcium 2021; 101:102502. [PMID: 34896699 DOI: 10.1016/j.ceca.2021.102502] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 11/14/2021] [Accepted: 11/15/2021] [Indexed: 02/07/2023]
Abstract
Endothelial colony forming cells (ECFCs) represent the most suitable cellular substrate to induce revascularization of ischemic tissues. Recently, optical excitation of the light-sensitive conjugated polymer, regioregular Poly (3-hexyl-thiophene), rr-P3HT, was found to stimulate ECFC proliferation and tube formation by activating the non-selective cation channel, Transient Receptor Potential Vanilloid 1 (TRPV1). Herein, we adopted a multidisciplinary approach, ranging from intracellular Ca2+ imaging to pharmacological manipulation and genetic suppression of TRPV1 expression, to investigate the effects of photoexcitation on intracellular Ca2+ concentration ([Ca2+]i) in circulating ECFCs plated on rr-P3HT thin films. Polymer-mediated optical excitation induced a long-lasting increase in [Ca2+]i that could display an oscillatory pattern at shorter light stimuli. Pharmacological and genetic manipulation revealed that the Ca2+ response to light was triggered by extracellular Ca2+ entry through TRPV1, whose activation required the production of reactive oxygen species at the interface between rr-P3HT and the cell membrane. Light-induced TRPV1-mediated Ca2+ entry was able to evoke intracellular Ca2+ release from the endoplasmic reticulum through inositol-1,4,5-trisphosphate receptors, followed by store-operated Ca2+ entry on the plasma membrane. These data show that TRPV1 may serve as a decoder at the interface between rr-P3HT thin films and ECFCs to translate optical excitation in pro-angiogenic Ca2+ signals.
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Affiliation(s)
- Sharon Negri
- Department of Biology and Biotechnology "Lazzaro Spallanzani", University of Pavia, 27100 Pavia, Italy
| | - Pawan Faris
- Department of Biology and Biotechnology "Lazzaro Spallanzani", University of Pavia, 27100 Pavia, Italy
| | - Gabriele Tullii
- Center for Nano Science and Technology@PoliMi, Istituto Italiano di Tecnologia, 20133 Milano, Italy
| | - Mauro Vismara
- Department of Biology and Biotechnology "Lazzaro Spallanzani", University of Pavia, 27100 Pavia, Italy
| | - Alessandro F Pellegata
- Center for Nano Science and Technology@PoliMi, Istituto Italiano di Tecnologia, 20133 Milano, Italy
| | - Francesco Lodola
- Center for Nano Science and Technology@PoliMi, Istituto Italiano di Tecnologia, 20133 Milano, Italy
| | - Gianni Guidetti
- Department of Biology and Biotechnology "Lazzaro Spallanzani", University of Pavia, 27100 Pavia, Italy
| | - Vittorio Rosti
- Center for the Study of Myelofibrosis, Laboratory of Biochemistry, Biotechnology and Advanced Diagnosis, IRCCS Policlinico San Matteo Foundation, 27100 Pavia, Italy
| | - Maria Rosa Antognazza
- Center for Nano Science and Technology@PoliMi, Istituto Italiano di Tecnologia, 20133 Milano, Italy.
| | - Francesco Moccia
- Department of Biology and Biotechnology "Lazzaro Spallanzani", University of Pavia, 27100 Pavia, Italy.
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Biringer RG. A review of non-prostanoid, eicosanoid receptors: expression, characterization, regulation, and mechanism of action. J Cell Commun Signal 2021; 16:5-46. [PMID: 34173964 DOI: 10.1007/s12079-021-00630-6] [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: 05/21/2021] [Accepted: 06/07/2021] [Indexed: 11/29/2022] Open
Abstract
Eicosanoid signaling controls a wide range of biological processes from blood pressure homeostasis to inflammation and resolution thereof to the perception of pain and to cell survival itself. Disruption of normal eicosanoid signaling is implicated in numerous disease states. Eicosanoid signaling is facilitated by G-protein-coupled, eicosanoid-specific receptors and the array of associated G-proteins. This review focuses on the expression, characterization, regulation, and mechanism of action of non-prostanoid, eicosanoid receptors.
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Affiliation(s)
- Roger G Biringer
- College of Osteopathic Medicine, Lake Erie College of Osteopathic Medicine, 5000 Lakewood Ranch Blvd, Bradenton, FL, 34211, USA.
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4
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Wang X, Xiao Q, Zhu Y, Qi H, Qu D, Yao Y, Jia Y, Guo J, Cheng J, Ji Y, Li G, Tao J. Glycosylation of β1 subunit plays a pivotal role in the toxin sensitivity and activation of BK channels. J Venom Anim Toxins Incl Trop Dis 2021; 27:e20200182. [PMID: 34149831 PMCID: PMC8183112 DOI: 10.1590/1678-9199-jvatitd-2020-0182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Background: The accessory β1 subunits, regulating the pharmacological and biophysical properties of BK channels, always undergo post-translational modifications, especially glycosylation. To date, it remains elusive whether the glycosylation contributes to the regulation of BK channels by β1 subunits. Methods: Herein, we combined the electrophysiological approach with molecular mutations and biochemical manipulation to investigate the function roles of N-glycosylation in β1 subunits. Results: The results show that deglycosylation of β1 subunits through double-site mutations (β1 N80A/N142A or β1 N80Q/N142Q) could significantly increase the inhibitory potency of iberiotoxin, a specific BK channel blocker. The deglycosylated channels also have a different sensitivity to martentoxin, another BK channel modulator with some remarkable effects as reported before. On the contrary to enhancing effects of martentoxin on glycosylated BK channels under the presence of cytoplasmic Ca2+, deglycosylated channels were not affected by the toxin. However, the deglycosylated channels were surprisingly inhibited by martentoxin under the absence of cytoplasmic Ca2+, while the glycosylated channels were not inhibited under this same condition. In addition, wild type BK (α+β1) channels treated with PNGase F also showed the same trend of pharmacological results to the mutants. Similar to this modulation of glycosylation on BK channel pharmacology, the deglycosylated forms of the channels were activated at a faster speed than the glycosylated ones. However, the V1/2 and slope were not changed by the glycosylation. Conclusion: The present study reveals that glycosylation is an indispensable determinant of the modulation of β1-subunit on BK channel pharmacology and its activation. The loss of glycosylation of β1 subunits could lead to the dysfunction of BK channel, resulting in a pathological state.
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Affiliation(s)
- Xiaoli Wang
- Institute of Biomembrane and Biopharmaceutics, Shanghai University, Shanghai, China
| | - Qian Xiao
- Department of Neurology and Central Laboratory, Putuo Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Yudan Zhu
- Department of Neurology and Central Laboratory, Putuo Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Hong Qi
- Institute of Biomembrane and Biopharmaceutics, Shanghai University, Shanghai, China
| | - Dongxiao Qu
- Department of Neurology and Central Laboratory, Putuo Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Yu Yao
- Institute of Biomembrane and Biopharmaceutics, Shanghai University, Shanghai, China
| | - Yuxiang Jia
- Institute of Biomembrane and Biopharmaceutics, Shanghai University, Shanghai, China
| | - Jingkan Guo
- Institute of Biomembrane and Biopharmaceutics, Shanghai University, Shanghai, China.,Xinhua Translational Institute for Cancer Pain, Shanghai, China
| | - Jiwei Cheng
- Department of Neurology and Central Laboratory, Putuo Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China.,Putuo Clinical Medical School, Anhui Medical University, Shanghai, China
| | - Yonghua Ji
- Institute of Biomembrane and Biopharmaceutics, Shanghai University, Shanghai, China.,Xinhua Translational Institute for Cancer Pain, Shanghai, China
| | - Guoyi Li
- Department of Neurology and Central Laboratory, Putuo Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China.,Putuo Clinical Medical School, Anhui Medical University, Shanghai, China
| | - Jie Tao
- Department of Neurology and Central Laboratory, Putuo Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China.,Putuo Clinical Medical School, Anhui Medical University, Shanghai, China
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5
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Functional Expression of TRPV1 Ion Channel in the Canine Peripheral Blood Mononuclear Cells. Int J Mol Sci 2021; 22:ijms22063177. [PMID: 33804707 PMCID: PMC8003907 DOI: 10.3390/ijms22063177] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 03/12/2021] [Accepted: 03/17/2021] [Indexed: 12/25/2022] Open
Abstract
TRPV1, known as a capsaicin receptor, is the best-described transient receptor potential (TRP) ion channel. Recently, it was shown to be expressed by non-excitable cells such as lymphocytes. However, the data regarding the functional expression of the TRPV1 channel in the immune cells are often contradictory. In the present study, we performed a phylogenetical analysis of the canine TRP ion channels, we assessed the expression of TRPV1 in the canine peripheral blood mononuclear cells (PBMC) by qPCR and Western blot, and we determined the functionality of TRPV1 by whole-cell patch-clamp recordings and calcium assay. We found high expression of TRPV2, -M2, and -M7 in the canine PBMCs, while expression of TRPV1, -V4 and, -M5 was relatively low. We confirmed that TRPV1 is expressed on the protein level in the PBMC and it localizes in the plasma membrane. The whole-cell patch-clamp recording revealed that capsaicin application caused a significant increase in the current density. Similarly, the results from the calcium assay show a dose-dependent increase in intracellular calcium level in the presence of capsaicin that was partially abolished by capsazepine. Our study confirms the expression of TRPV1 ion channel on both mRNA and protein levels in the canine PBMC and indicates that the ion channel is functional.
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Goretzki B, Guhl C, Tebbe F, Harder JM, Hellmich UA. Unstructural Biology of TRP Ion Channels: The Role of Intrinsically Disordered Regions in Channel Function and Regulation. J Mol Biol 2021; 433:166931. [PMID: 33741410 DOI: 10.1016/j.jmb.2021.166931] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2021] [Revised: 03/02/2021] [Accepted: 03/06/2021] [Indexed: 12/13/2022]
Abstract
The first genuine high-resolution single particle cryo-electron microscopy structure of a membrane protein determined was a transient receptor potential (TRP) ion channel, TRPV1, in 2013. This methodical breakthrough opened up a whole new world for structural biology and ion channel aficionados alike. TRP channels capture the imagination due to the sheer endless number of tasks they carry out in all aspects of animal physiology. To date, structures of at least one representative member of each of the six mammalian TRP channel subfamilies as well as of a few non-mammalian families have been determined. These structures were instrumental for a better understanding of TRP channel function and regulation. However, all of the TRP channel structures solved so far are incomplete since they miss important information about highly flexible regions found mostly in the channel N- and C-termini. These intrinsically disordered regions (IDRs) can represent between a quarter to almost half of the entire protein sequence and act as important recruitment hubs for lipids and regulatory proteins. Here, we analyze the currently available TRP channel structures with regard to the extent of these "missing" regions and compare these findings to disorder predictions. We discuss select examples of intra- and intermolecular crosstalk of TRP channel IDRs with proteins and lipids as well as the effect of splicing and post-translational modifications, to illuminate their importance for channel function and to complement the prevalently discussed structural biology of these versatile and fascinating proteins with their equally relevant 'unstructural' biology.
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Affiliation(s)
- Benedikt Goretzki
- Faculty of Chemistry and Earth Sciences, Institute of Organic Chemistry and Macromolecular Chemistry, Friedrich-Schiller-University, Humboldtstrasse 10, 07743 Jena, Germany; Centre for Biomolecular Magnetic Resonance (BMRZ), Goethe-University, Max-von-Laue-Strasse 9, 60438 Frankfurt, Germany
| | - Charlotte Guhl
- Faculty of Chemistry and Earth Sciences, Institute of Organic Chemistry and Macromolecular Chemistry, Friedrich-Schiller-University, Humboldtstrasse 10, 07743 Jena, Germany; Centre for Biomolecular Magnetic Resonance (BMRZ), Goethe-University, Max-von-Laue-Strasse 9, 60438 Frankfurt, Germany; TransMED - Mainz Research School of Translational Medicine, Johannes Gutenberg-University, University Medical Center, Langenbeckstr. 1, 55131 Mainz, Germany
| | - Frederike Tebbe
- Faculty of Chemistry and Earth Sciences, Institute of Organic Chemistry and Macromolecular Chemistry, Friedrich-Schiller-University, Humboldtstrasse 10, 07743 Jena, Germany; Centre for Biomolecular Magnetic Resonance (BMRZ), Goethe-University, Max-von-Laue-Strasse 9, 60438 Frankfurt, Germany
| | - Jean-Martin Harder
- Faculty of Chemistry and Earth Sciences, Institute of Organic Chemistry and Macromolecular Chemistry, Friedrich-Schiller-University, Humboldtstrasse 10, 07743 Jena, Germany
| | - Ute A Hellmich
- Faculty of Chemistry and Earth Sciences, Institute of Organic Chemistry and Macromolecular Chemistry, Friedrich-Schiller-University, Humboldtstrasse 10, 07743 Jena, Germany; Centre for Biomolecular Magnetic Resonance (BMRZ), Goethe-University, Max-von-Laue-Strasse 9, 60438 Frankfurt, Germany; TransMED - Mainz Research School of Translational Medicine, Johannes Gutenberg-University, University Medical Center, Langenbeckstr. 1, 55131 Mainz, Germany; Cluster of Excellence Balance of the Microverse, Friedrich-Schiller-University, 07743 Jena, Germany.
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7
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Faris P, Ferulli F, Vismara M, Tanzi M, Negri S, Rumolo A, Lefkimmiatis K, Maestri M, Shekha M, Pedrazzoli P, Guidetti GF, Montagna D, Moccia F. Hydrogen Sulfide-Evoked Intracellular Ca 2+ Signals in Primary Cultures of Metastatic Colorectal Cancer Cells. Cancers (Basel) 2020; 12:cancers12113338. [PMID: 33187307 PMCID: PMC7696676 DOI: 10.3390/cancers12113338] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Revised: 11/05/2020] [Accepted: 11/06/2020] [Indexed: 02/07/2023] Open
Abstract
Simple Summary Colorectal cancer (CRC) is the most common type of gastrointestinal cancer and the third most predominant cancer in the world. CRC is potentially curable with surgical resection of the primary tumor. The clinical problem of colorectal cancer, however, is the spread and outgrowth of metastases, which are difficult to eradicate and lead to a patient’s death. The failure of conventional treatment to significantly improved outcomes in mCRC has prompted the search for alternative molecular targets with the goal of ameliorating the prognosis of these patients. The present investigation revealed that exogenous delivery of hydrogen sulfide (H2S) suppresses proliferation in metastatic colorectal cancer cells by inducing an increase in intracellular Ca2+ concentration. H2S was effective on metastatic, but not normal, cells. Therefore, we propose that exogenous administration of H2S to patients affected by metastatic colorectal carcinoma could represent a promising therapeutic alternative. Abstract Exogenous administration of hydrogen sulfide (H2S) is emerging as an alternative anticancer treatment. H2S-releasing compounds have been shown to exert a strong anticancer effect by suppressing proliferation and/or inducing apoptosis in several cancer cell types, including colorectal carcinoma (CRC). The mechanism whereby exogenous H2S affects CRC cell proliferation is yet to be clearly elucidated, but it could involve an increase in intracellular Ca2+ concentration ([Ca2+]i). Herein, we sought to assess for the first time whether (and how) sodium hydrosulfide (NaHS), one of the most widely employed H2S donors, induced intracellular Ca2+ signals in primary cultures of human metastatic CRC (mCRC) cells. We provided the evidence that NaHS induced extracellular Ca2+ entry in mCRC cells by activating the Ca2+-permeable channel Transient Receptor Potential Vanilloid 1 (TRPV1) followed by the Na+-dependent recruitment of the reverse-mode of the Na+/Ca2+ (NCX) exchanger. In agreement with these observations, TRPV1 protein was expressed and capsaicin, a selective TRPV1 agonist, induced Ca2+ influx by engaging both TRPV1 and NCX in mCRC cells. Finally, NaHS reduced mCRC cell proliferation, but did not promote apoptosis or aberrant mitochondrial depolarization. These data support the notion that exogenous administration of H2S may prevent mCRC cell proliferation through an increase in [Ca2+]i, which is triggered by TRPV1.
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Affiliation(s)
- Pawan Faris
- Laboratory of General Physiology, Department of Biology and Biotechnology “L. Spallanzani”, University of Pavia, 27100 Pavia, Italy; (P.F.); (S.N.)
- Department of Biology, Cihan University-Erbil, 44001 Erbil, Iraq
| | - Federica Ferulli
- Laboratory of Immunology Transplantation, Foundation IRCCS Policlinico San Matteo, 27100 Pavia, Italy; (F.F.); (M.T.); (A.R.)
| | - Mauro Vismara
- Laboratory of Biochemistry, Department of Biology and Biotechnology “L. Spallanzani”, University of Pavia, 27100 Pavia, Italy; (M.V.); (G.F.G.)
| | - Matteo Tanzi
- Laboratory of Immunology Transplantation, Foundation IRCCS Policlinico San Matteo, 27100 Pavia, Italy; (F.F.); (M.T.); (A.R.)
| | - Sharon Negri
- Laboratory of General Physiology, Department of Biology and Biotechnology “L. Spallanzani”, University of Pavia, 27100 Pavia, Italy; (P.F.); (S.N.)
| | - Agnese Rumolo
- Laboratory of Immunology Transplantation, Foundation IRCCS Policlinico San Matteo, 27100 Pavia, Italy; (F.F.); (M.T.); (A.R.)
| | - Kostantinos Lefkimmiatis
- Department of Molecular Medicine, University of Pavia, 27100 Pavia, Italy;
- Veneto Institute of Molecular Medicine, Foundation for Advanced Biomedical Research, 35131 Padua, Italy
| | - Marcello Maestri
- Medical Surgery, Foundation IRCCS Policlinico San Matteo, 27100 Pavia, Italy;
| | - Mudhir Shekha
- Faculty of Science, Department of Medical Analysis, Tishk International University-Erbil, 44001 Erbil, Iraq;
| | - Paolo Pedrazzoli
- Medical Oncology, Foundation IRCCS Policlinico San Matteo, 27100 Pavia, Italy;
| | - Gianni Francesco Guidetti
- Laboratory of Biochemistry, Department of Biology and Biotechnology “L. Spallanzani”, University of Pavia, 27100 Pavia, Italy; (M.V.); (G.F.G.)
| | - Daniela Montagna
- Laboratory of Immunology Transplantation, Foundation IRCCS Policlinico San Matteo, 27100 Pavia, Italy; (F.F.); (M.T.); (A.R.)
- Diagnostic and Pediatric, Department of Sciences Clinic-Surgical, University of Pavia, 27100 Pavia, Italy
- Correspondence: (D.M.); (F.M.); Tel.: +39-382-987-619 (F.M.)
| | - Francesco Moccia
- Laboratory of General Physiology, Department of Biology and Biotechnology “L. Spallanzani”, University of Pavia, 27100 Pavia, Italy; (P.F.); (S.N.)
- Correspondence: (D.M.); (F.M.); Tel.: +39-382-987-619 (F.M.)
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8
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de Oliveira Leite G, Santos SAAR, Bezerra FMDH, Sena E Silva FE, de Castro Ribeiro AD, Roma RR, Silva RRS, Santos MHC, Santos ALE, Teixeira CS, Campos AR. Is the orofacial antinociceptive effect of lectins intrinsically related to their specificity to monosaccharides? Int J Biol Macromol 2020; 161:1079-1085. [PMID: 32561277 DOI: 10.1016/j.ijbiomac.2020.06.132] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2020] [Revised: 03/23/2020] [Accepted: 06/14/2020] [Indexed: 01/24/2023]
Abstract
Lectins are proteins of non-immunological origin that may play several biological applications, of which we can highlight the anti-inflammatory and antinociceptive activities. In this work, we evaluated the possible effect of orofacial antinociceptive activity of three plant lectins, Dioclea violacea (DVL - Man/Glc-binding), Vatairea macrocarpa (VML - Gal-binding) and PPL (Parkia platycephala - Man/Glc-binding) in adult zebrafish. Acute nociception was induced by menthol (1.2 μM), or capsaicin (4.93 μM) applied into in the upper lip (5.0 μL) of adult wild zebrafish. Zebrafish were pretreated by intraperitoneal injection (20 μL) with vehicle (Control) or lectins (0.025; 0.05 or 0.1 mg/mL) 30 min before induction. The effect of lectins on zebrafish locomotor behavior was evaluated with the open field test. Naive groups (n = 8) were included in all tests. Our results indicate that only PPL presented antinociceptive induced by capsaicin, suggesting the potential clinical application of PPL as inhibitor of orofacial nociception and that this effect may be due to the modulation of TRPV1 channel. In conclusion, lectins that exhibit affinity to the same or different carbohydrates do not necessarily have an antinociceptive effect on the orofacial nociception model, indicating that the glycan carbohydrate binding pattern may be related to the effect on nociception inhibition.
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Affiliation(s)
| | | | | | | | | | - Renato Rodrigues Roma
- Centro de Ciências Agrárias e Ambientais, Universidade Federal do Maranhão, Chapadinha, Maranhão, Brazil
| | | | - Maria Helena Cruz Santos
- Centro de Ciências Agrárias e Ambientais, Universidade Federal do Maranhão, Chapadinha, Maranhão, Brazil
| | - Ana Lucia Estevam Santos
- Centro de Ciências Agrárias e Ambientais, Universidade Federal do Maranhão, Chapadinha, Maranhão, Brazil
| | - Claudener Souza Teixeira
- Centro de Ciências Agrárias e Ambientais, Universidade Federal do Maranhão, Chapadinha, Maranhão, Brazil
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The transient receptor potential vanilloid 4 (TRPV4) ion channel mediates protease activated receptor 1 (PAR1)-induced vascular hyperpermeability. J Transl Med 2020; 100:1057-1067. [PMID: 32341518 PMCID: PMC10080476 DOI: 10.1038/s41374-020-0430-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2020] [Revised: 04/02/2020] [Accepted: 04/02/2020] [Indexed: 12/27/2022] Open
Abstract
Endothelial barrier disruption is a hallmark of tissue injury, edema, and inflammation. Vascular endothelial cells express the G protein-coupled receptor (GPCR) protease acctivated receptor 1 (PAR1) and the ion channel transient receptor potential vanilloid 4 (TRPV4), and these signaling proteins are known to respond to inflammatory conditions and promote edema through remodeling of cell-cell junctions and modulation of endothelial barriers. It has previously been established that signaling initiated by the related protease activated receptor 2 (PAR2) is enhanced by TRPV4 in sensory neurons and that this functional interaction plays a critical role in the development of neurogenic inflammation and nociception. Here, we investigated the PAR1-TRPV4 axis, to determine if TRPV4 plays a similar role in the control of edema mediated by thrombin-induced signaling. Using Evans Blue permeation and retention as an indication of increased vascular permeability in vivo, we showed that TRPV4 contributes to PAR1-induced vascular hyperpermeability in the airways and upper gastrointestinal tract of mice. TRPV4 contributes to sustained PAR1-induced Ca2+ signaling in recombinant cell systems and to PAR1-dependent endothelial junction remodeling in vitro. This study supports the role of GPCR-TRP channel functional interactions in inflammatory-associated changes to vascular function and indicates that TRPV4 is a signaling effector for multiple PAR family members.
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10
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Incorporation of one N-glycosylation-deficient subunit within a tetramer of HCN2 channel is tolerated. Neuroreport 2019; 30:998-1003. [PMID: 31503201 DOI: 10.1097/wnr.0000000000001310] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels are glycoproteins N-glycosylated at a specific asparagine residue in the S5-S6 linker region. Previous reports suggested that N-glycosylation-deficient HCN2 N380Q (NQ) channels fail to properly target to the plasma membrane and are unable to form functional ion channels. HCN channels are known to homo- and hetero-oligomerize and it is not known whether HCN2-NQ subunits can oligomerize with wild type (wt) N-glycosylated subunits to form a tetrameric assembly. In the present study, homomeric NQ-mutant resulted in no current, cRNA titration experiments controlling the amount of wt-to-NQ injected into Xenopus oocytes indicated that the observed currents were consistent with a model where presence of a single nonglycosylated subunit in a tetrameric oligomer is tolerated forming functional channels. The activation voltage-dependence described by half-activation voltage and slope factor, and the reversal potential of the wt-NQ oligomeric channels were identical to the wt only tetrameric channels. Further incorporation of the nonglycosylated subunit rendered the channels nonconductive or not incorporated into the plasma membrane.
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11
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Maksoud MJE, Tellios V, An D, Xiang Y, Lu W. Nitric oxide upregulates microglia phagocytosis and increases transient receptor potential vanilloid type 2 channel expression on the plasma membrane. Glia 2019; 67:2294-2311. [DOI: 10.1002/glia.23685] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Revised: 07/02/2019] [Accepted: 07/06/2019] [Indexed: 12/21/2022]
Affiliation(s)
- Matthew J. E. Maksoud
- Graduate Program of Neuroscience The University of Western Ontario London Canada
- Department of Molecular Medicine Robarts Research Institute, The University of Western Ontario London Canada
| | - Vasiliki Tellios
- Graduate Program of Neuroscience The University of Western Ontario London Canada
- Department of Molecular Medicine Robarts Research Institute, The University of Western Ontario London Canada
| | - Dong An
- Department of Molecular Medicine Robarts Research Institute, The University of Western Ontario London Canada
| | - Yun‐Yan Xiang
- Department of Molecular Medicine Robarts Research Institute, The University of Western Ontario London Canada
| | - Wei‐Yang Lu
- Graduate Program of Neuroscience The University of Western Ontario London Canada
- Department of Molecular Medicine Robarts Research Institute, The University of Western Ontario London Canada
- Department of Physiology and Pharmacology The University of Western Ontario London Canada
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Xu L, Yang F. [Structural modeling of selectivity filter in transient receptor pontential melastatin 8 ion channel]. Zhejiang Da Xue Xue Bao Yi Xue Ban 2019; 48:19-24. [PMID: 31102353 PMCID: PMC8800648 DOI: 10.3785/j.issn.1008-9292.2019.02.04] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Accepted: 10/19/2018] [Indexed: 06/09/2023]
Abstract
OBJECTIVE To construct a three-dimensional structural model for the selectivity filter in the transient receptor pontential melastatin 8 (TRPM8) ion channel. METHODS In the Rosetta computational structural biology suite, multiple rounds of de novo modeling with the kinematic loop closure algorithm were performed. RESULTS After nine rounds of computational modeling, we obtained the models of the selectivity filter within the TRPM8 channel with the lowest energy and high convergence. The model showed that the sidechain of D918 points were away from the central ion permeation pathway, while the sidechains of Q914, D920 and T923 pointed towards it. The glycosylation site N934 was located outside the pore region and its side chain directed to the extracellular water environment. CONCLUSIONS A three-dimensional structural model for the selectivity filter in the TRPM8 ion channel was constructed, which provides reliable structural information for exploring the mechanism of ion selectivity.
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Affiliation(s)
- Lizhen Xu
- Department of Biophysics, Zhejiang University School of Medicine, Hangzhou 310058, China
| | - Fan Yang
- Department of Biophysics, Zhejiang University School of Medicine, Hangzhou 310058, China
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13
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Modulation of Endocannabinoid-Binding Receptors in Human Neuroblastoma Cells by Tunicamycin. Molecules 2019; 24:molecules24071432. [PMID: 30979007 PMCID: PMC6479803 DOI: 10.3390/molecules24071432] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Revised: 04/09/2019] [Accepted: 04/09/2019] [Indexed: 01/22/2023] Open
Abstract
Endocannabinoid (eCB)-binding receptors can be modulated by several ligands and membrane environment, yet the effect of glycosylation remains to be assessed. In this study, we used human neuroblastoma SH-SY5Y cells to interrogate whether expression, cellular localization, and activity of eCB-binding receptors may depend on N-linked glycosylation. Following treatment with tunicamycin (a specific inhibitor of N-linked glycosylation) at the non-cytotoxic dose of 1 µg/mL, mRNA, protein levels and localization of eCB-binding receptors, as well as N-acetylglucosamine (GlcNAc) residues, were evaluated in SH-SY5Y cells by means of quantitative real-time reverse transcriptase-polymerase chain reaction (qRT-PCR), fluorescence-activated cell sorting (FACS), and confocal microscopy, respectively. In addition, the activity of type-1 and type-2 cannabinoid receptors (CB1 and CB2) was assessed by means of rapid binding assays. Significant changes in gene and protein expression were found upon tunicamycin treatment for CB1 and CB2, as well as for GPR55 receptors, but not for transient receptor potential vanilloid 1 (TRPV1). Deglycosylation experiments with N-glycosidase-F and immunoblot of cell membranes derived from SH-SY5Y cells confirmed the presence of one glycosylated form in CB1 (70 kDa), that was reduced by tunicamycin. Morphological studies demonstrated the co-localization of CB1 with GlcNAc residues, and showed that tunicamycin reduced CB1 membrane expression with a marked nuclear localization, as confirmed by immunoblotting. Cleavage of the carbohydrate side chain did not modify CB receptor binding affinity. Overall, these results support N-linked glycosylation as an unprecedented post-translational modification that may modulate eCB-binding receptors’ expression and localization, in particular for CB1.
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14
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Santos AL, Leite GO, Carneiro RF, Roma RR, Santos VF, Santos MH, Pereira RO, Silva RC, Nagano CS, Sampaio AH, Rocha BA, Delatorre P, Campos AR, Teixeira CS. Purification and biophysical characterization of a mannose/N-acetyl-d-glucosamine-specific lectin from Machaerium acutifolium and its effect on inhibition of orofacial pain via TRPV1 receptor. Arch Biochem Biophys 2019; 664:149-156. [DOI: 10.1016/j.abb.2019.02.009] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Revised: 02/07/2019] [Accepted: 02/13/2019] [Indexed: 12/12/2022]
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15
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Salas MM, Clifford JL, Hayden JR, Iadarola MJ, Averitt DL. Local Resiniferatoxin Induces Long-Lasting Analgesia in a Rat Model of Full Thickness Thermal Injury. PAIN MEDICINE 2018; 18:2453-2465. [PMID: 27794548 DOI: 10.1093/pm/pnw260] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Objective Opioid-based analgesics are a major component of the lengthy pain management of burn patients, including military service members, but are problematic due to central nervous system-mediated side effects. Peripheral analgesia via targeted ablation of nociceptive nerve endings that express the transient receptor potential vanilloid channel 1 (TRPV1) may provide an improved approach. We hypothesized that local injection of the TRPV1 agonist resiniferatoxin (RTX) would produce long-lasting analgesia in a rat model of pain associated with burn injury. Methods Baseline sensitivities to thermal and mechanical stimuli were measured in male and female Sprague-Dawley rats. Under anesthesia, a 100 °C metal probe was placed on the right hind paw for 30 seconds, and sensitivity was reassessed 72 hours following injury. Rats received RTX (0.25 μg/100 μL; ipl) into the injured hind paw, and sensitivity was reassessed across three weeks. Tissues were collected from a separate group of rats at 24 hours and/or one week post-RTX for pathological analyses of the injured hind paw, dorsal spinal cord c-Fos, and primary afferent neuropeptide immunoreactivity. Results Local RTX reversed burn pain behaviors within 24 hours, which lasted through recovery at three weeks. At one week following RTX, decreased c-Fos and primary afferent neuropeptide immunoreactivities were observed in the dorsal horn, while plantar burn pathology was unaltered. Conclusions These results indicate that local RTX induces long-lasting analgesia in a rat model of pain associated with burn. While opioids are undesirable in trauma patients due to side effects, RTX may provide valuable long-term, nonopioid analgesia for burn patients.
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Affiliation(s)
- Margaux M Salas
- Pain Management Research Area, United States Army Institute of Surgical Research, JBSA Fort Sam Houston, Texas
| | - John L Clifford
- Pain Management Research Area, United States Army Institute of Surgical Research, JBSA Fort Sam Houston, Texas
| | - Jessica R Hayden
- Pain Management Research Area, United States Army Institute of Surgical Research, JBSA Fort Sam Houston, Texas
| | - Michael J Iadarola
- Department of Perioperative Medicine, Clinical Center, National Institutes of Health, Bethesda, Maryland
| | - Dayna L Averitt
- Department of Biology, Texas Woman's University, Denton, Texas, USA
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16
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Miller JJ, Aoki K, Moehring F, Murphy CA, O’Hara CL, Tiemeyer M, Stucky CL, Dahms NM. Neuropathic pain in a Fabry disease rat model. JCI Insight 2018; 3:99171. [PMID: 29563343 PMCID: PMC5926911 DOI: 10.1172/jci.insight.99171] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Accepted: 02/07/2018] [Indexed: 02/06/2023] Open
Abstract
Fabry disease, the most common lysosomal storage disease, affects multiple organs and results in a shortened life span. This disease is caused by a deficiency of the lysosomal enzyme α-galactosidase A, which leads to glycosphingolipid accumulation in many cell types. Neuropathic pain is an early and severely debilitating symptom in patients with Fabry disease, but the cellular and molecular mechanisms that cause the pain are unknown. We generated a rat model of Fabry disease, the first nonmouse model to our knowledge. Fabry rats had substantial serum and tissue accumulation of α-galactosyl glycosphingolipids and had pronounced mechanical pain behavior. Additionally, Fabry rat dorsal root ganglia displayed global N-glycan alterations, sensory neurons were laden with inclusions, and sensory neuron somata exhibited prominent sensitization to mechanical force. We found that the cation channel transient receptor potential ankyrin 1 (TRPA1) is sensitized in Fabry rat sensory neurons and that TRPA1 antagonism reversed the behavioral mechanical sensitization. This study points toward TRPA1 as a potentially novel target to treat the pain experienced by patients with Fabry disease.
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Affiliation(s)
- James J. Miller
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Kazuhiro Aoki
- Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia, USA
| | - Francie Moehring
- Department of Cell Biology, Neurobiology, & Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Carly A. Murphy
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Crystal L. O’Hara
- Department of Cell Biology, Neurobiology, & Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Michael Tiemeyer
- Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia, USA
| | - Cheryl L. Stucky
- Department of Cell Biology, Neurobiology, & Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Nancy M. Dahms
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
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17
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Ortíz-Rentería M, Juárez-Contreras R, González-Ramírez R, Islas LD, Sierra-Ramírez F, Llorente I, Simon SA, Hiriart M, Rosenbaum T, Morales-Lázaro SL. TRPV1 channels and the progesterone receptor Sig-1R interact to regulate pain. Proc Natl Acad Sci U S A 2018; 115:E1657-E1666. [PMID: 29378958 PMCID: PMC5816171 DOI: 10.1073/pnas.1715972115] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The Transient Receptor Potential Vanilloid 1 (TRPV1) ion channel is expressed in nociceptors where, when activated by chemical or thermal stimuli, it functions as an important transducer of painful and itch-related stimuli. Although the interaction of TRPV1 with proteins that regulate its function has been previously explored, their modulation by chaperones has not been elucidated, as is the case for other mammalian TRP channels. Here we show that TRPV1 physically interacts with the Sigma 1 Receptor (Sig-1R), a chaperone that binds progesterone, an antagonist of Sig-1R and an important neurosteroid associated to the modulation of pain. Antagonism of Sig-1R by progesterone results in the down-regulation of TRPV1 expression in the plasma membrane of sensory neurons and, consequently, a decrease in capsaicin-induced nociceptive responses. This is observed both in males treated with a synthetic antagonist of Sig-1R and in pregnant females where progesterone levels are elevated. This constitutes a previously undescribed mechanism by which TRPV1-dependent nociception and pain can be regulated.
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Affiliation(s)
- Miguel Ortíz-Rentería
- Departamento de Neurociencia Cognitiva, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, 04510 Coyoacán, Ciudad de México, México
| | - Rebeca Juárez-Contreras
- Departamento de Neurociencia Cognitiva, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, 04510 Coyoacán, Ciudad de México, México
| | - Ricardo González-Ramírez
- Departamento de Biología Molecular e Histocompatibilidad, Hospital General Dr. Manuel Gea González, Secretaría de Salud, 14080 Tlalpan, Ciudad de México, México
| | - León D Islas
- Departamento de Fisiología, Facultad de Medicina, Universidad Nacional Autónoma de México, 04510 Coyoacán, Ciudad de México, México
| | - Félix Sierra-Ramírez
- Departamento de Neurociencia Cognitiva, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, 04510 Coyoacán, Ciudad de México, México
| | - Itzel Llorente
- Departamento de Neurociencia Cognitiva, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, 04510 Coyoacán, Ciudad de México, México
| | - Sidney A Simon
- Department of Neurobiology, Duke University, Durham, NC 27710
| | - Marcia Hiriart
- Departamento de Neurociencia Cognitiva, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, 04510 Coyoacán, Ciudad de México, México
| | - Tamara Rosenbaum
- Departamento de Neurociencia Cognitiva, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, 04510 Coyoacán, Ciudad de México, México
| | - Sara L Morales-Lázaro
- Departamento de Neurociencia Cognitiva, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, 04510 Coyoacán, Ciudad de México, México;
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18
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Kong WL, Peng YY, Peng BW. Modulation of neuroinflammation: Role and therapeutic potential of TRPV1 in the neuro-immune axis. Brain Behav Immun 2017; 64:354-366. [PMID: 28342781 DOI: 10.1016/j.bbi.2017.03.007] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Revised: 03/04/2017] [Accepted: 03/14/2017] [Indexed: 02/07/2023] Open
Abstract
Transient receptor potential vanilloid type 1 channel (TRPV1), as a ligand-gated non-selective cation channel, has recently been demonstrated to have wide expression in the neuro-immune axis, where its multiple functions occur through regulation of both neuronal and non-neuronal activities. Growing evidence has suggested that TRPV1 is functionally expressed in glial cells, especially in the microglia and astrocytes. Glial cells perform immunological functions in response to pathophysiological challenges through pro-inflammatory or anti-inflammatory cytokines and chemokines in which TRPV1 is involved. Sustaining inflammation might mediate a positive feedback loop of neuroinflammation and exacerbate neurological disorders. Accumulating evidence has suggested that TRPV1 is closely related to immune responses and might be recognized as a molecular switch in the neuroinflammation of a majority of seizures and neurodegenerative diseases. In this review, we evidenced that inflammation modulates the expression and activity of TRPV1 in the central nervous system (CNS) and TRPV1 exerts reciprocal actions over neuroinflammatory processes. Together, the literature supports the hypothesis that TRPV1 may represent potential therapeutic targets in the neuro-immune axis.
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Affiliation(s)
- Wei-Lin Kong
- Department of Physiology, Hubei Provincial Key Laboratory of Developmentally Originated Disorder, Hubei Province Key Laboratory of Allergy and Immunology, School of Basic Medical Sciences, Wuhan University, Wuhan, Hubei, China
| | - Yuan-Yuan Peng
- Department of Physiology, Hubei Provincial Key Laboratory of Developmentally Originated Disorder, Hubei Province Key Laboratory of Allergy and Immunology, School of Basic Medical Sciences, Wuhan University, Wuhan, Hubei, China
| | - Bi-Wen Peng
- Department of Physiology, Hubei Provincial Key Laboratory of Developmentally Originated Disorder, Hubei Province Key Laboratory of Allergy and Immunology, School of Basic Medical Sciences, Wuhan University, Wuhan, Hubei, China.
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19
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Zhao R, Tsang SY. Versatile Roles of Intracellularly Located TRPV1 Channel. J Cell Physiol 2017; 232:1957-1965. [DOI: 10.1002/jcp.25704] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Accepted: 11/22/2016] [Indexed: 12/17/2022]
Affiliation(s)
- Rui Zhao
- School of Life Sciences; The Chinese University of Hong Kong; Hong Kong SAR China
| | - Suk Ying Tsang
- School of Life Sciences; The Chinese University of Hong Kong; Hong Kong SAR China
- State Key Laboratory of Agrobiotechnology; The Chinese University of Hong Kong; Hong Kong SAR China
- Key Laboratory for Regenerative Medicine, Ministry of Education; The Chinese University of Hong Kong; Hong Kong SAR China
- Centre for Novel Biomaterials; The Chinese University of Hong Kong; Hong Kong SAR China
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20
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Ortega-Guerrero A, Espinosa-Duran JM, Velasco-Medina J. TRPV1 channel as a target for cancer therapy using CNT-based drug delivery systems. EUROPEAN BIOPHYSICS JOURNAL: EBJ 2016; 45:423-33. [PMID: 26872481 DOI: 10.1007/s00249-016-1111-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2015] [Revised: 10/28/2015] [Accepted: 01/05/2016] [Indexed: 12/20/2022]
Abstract
Carbon nanotubes are being considered for the design of drug delivery systems (DDSs) due to their capacity to internalize molecules and control their release. However, for cellular uptake of drugs, this approach requires an active translocation pathway or a channel to transport the drug into the cell. To address this issue, it is suggested to use TRPV1 ion channels as a potential target for drug release by nano-DDSs since these channels are overexpressed in cancer cells and allow the permeation of large cationic molecules. Considering these facts, this work presents three studies using molecular dynamics simulations of a human TRPV1 (hTRPV1) channel built here. The purpose of these simulations is to study the interaction between a single-wall carbon nanotube (SWCNT) and hTRPV1, and the diffusion of doxorubicin (DOX) across hTRPV1 and across a POPC lipid membrane. The first study shows an attractive potential between the SWCNT surface and hTRPV1, tilting the adsorbed SWCNT. The second study shows low diffusion probability of DOX across the open hTRPV1 due to a high free energy barrier. Although, the potential energy between DOX and hTRPV1 reveals an attractive interaction while DOX is inside hTRPV1. These results suggest that if the channel is dilated, then DOX diffusion could occur. The third study shows a lower free energy barrier for DOX across the lipid membrane than for DOX across hTRPV1. Taking into account the results obtained, it is feasible to design novel nano-DDSs based on SWCNTs to accomplish controlled drug release into cells using as translocation pathway, the hTRPV1 ion channel.
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Affiliation(s)
- Andres Ortega-Guerrero
- School of Electrical and Electronics Engineering, Bionanoelectronics Research Group, Universidad del Valle, Cali, Colombia
| | - John M Espinosa-Duran
- Department of Chemistry, Center for Theoretical and Computational Nanoscience, Indiana University, Bloomington, IN, USA
| | - Jaime Velasco-Medina
- School of Electrical and Electronics Engineering, Bionanoelectronics Research Group, Universidad del Valle, Cali, Colombia.
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21
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Leunissen EHP, Blanchard MG, Sheedfar F, Lavrijsen M, van der Wijst J, Bindels RJM, Hoenderop JGJ. Urinary β-galactosidase stimulates Ca2+ transport by stabilizing TRPV5 at the plasma membrane. Glycobiology 2016; 26:472-81. [PMID: 26747426 DOI: 10.1093/glycob/cwv172] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2015] [Accepted: 12/28/2015] [Indexed: 01/26/2023] Open
Abstract
Transcellular Ca(2+)transport in the late distal convoluted tubule and connecting tubule (DCT2/CNT) of the kidney is a finely controlled process mediated by the transient receptor potential vanilloid type 5 (TRPV5) channel. A complex-type-N-glycan bound at the extracellular residue Asn358 of TRPV5 through post-translational glycosylation has been postulated to regulate the activity of TRPV5 channels. Using in vitro Ca(2+)transport assays, immunoblot analysis, immunohistochemistry, patch clamp electrophysiology and total internal reflection fluorescence microscopy, it is demonstrated that the glycosidase β-galactosidase (β-gal), an enzyme that hydrolyzes galactose, stimulates TRPV5 channel activity. However, the activity of the non-glycosylated TRPV(N358Q)mutant was not altered in the presence of β-gal, showing that the stimulation is dependent on the presence of the TRPV5N-glycan. In addition, β-gal was found to stimulate transcellular Ca(2+)transport in isolated mouse primary DCT2/CNT cells. β-gal expression was detected in the apical membrane of the proximal tubules, and the protein was found in mouse urine. In summary, β-gal is present in the pro-urine from where it is thought to stimulate TRPV5 activity.
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Affiliation(s)
- Elizabeth H P Leunissen
- Department of Physiology, Radboud University Medical Center, Radboud Institute for Molecular Life Sciences, Nijmegen 6500 HB, The Netherlands
| | - Maxime G Blanchard
- Department of Physiology, Radboud University Medical Center, Radboud Institute for Molecular Life Sciences, Nijmegen 6500 HB, The Netherlands
| | - Fareeba Sheedfar
- Department of Physiology, Radboud University Medical Center, Radboud Institute for Molecular Life Sciences, Nijmegen 6500 HB, The Netherlands
| | - Marla Lavrijsen
- Department of Physiology, Radboud University Medical Center, Radboud Institute for Molecular Life Sciences, Nijmegen 6500 HB, The Netherlands
| | - Jenny van der Wijst
- Department of Physiology, Radboud University Medical Center, Radboud Institute for Molecular Life Sciences, Nijmegen 6500 HB, The Netherlands
| | - René J M Bindels
- Department of Physiology, Radboud University Medical Center, Radboud Institute for Molecular Life Sciences, Nijmegen 6500 HB, The Netherlands
| | - Joost G J Hoenderop
- Department of Physiology, Radboud University Medical Center, Radboud Institute for Molecular Life Sciences, Nijmegen 6500 HB, The Netherlands
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Ferreira LGB, Faria RX. TRPing on the pore phenomenon: what do we know about transient receptor potential ion channel-related pore dilation up to now? J Bioenerg Biomembr 2016; 48:1-12. [PMID: 26728159 DOI: 10.1007/s10863-015-9634-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2015] [Accepted: 12/02/2015] [Indexed: 01/06/2023]
Abstract
Ion channels allow for rapid ion diffusion through the plasma membrane. In some conditions, ion channels induce changes in the critical plasma membrane permeability that permit 900-Da solutes to enter cells. This process is known as the pore phenomenon. Some transient receptor potential (TRP) channel subtypes have been highlighted such as the P2X7 receptor, plasma membrane VDAC-1 channel, and pannexin hemichannels. The TRP ion channels are considered multimodal transducers that respond to several kinds of stimuli. In addition, many TRP channel subtypes are involved in physiological and pathophysiological processes such as inflammation, pain, and cancer. The TRPA1, TRPM8, and TRPV1-4 subtypes have been shown to promote large-molecular-weight solute uptake, including impermeable fluorescent dyes, QX-314 hydrophilic lidocaine derivative, gabapentin, and antineoplastic drugs. This review discusses the current knowledge of TRP-associated pores and encourages scientists to study their features and explore them as novel therapeutic tools.
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Affiliation(s)
- L G B Ferreira
- Laboratory of Inflammation, Oswaldo Cruz Institute, FIOCRUZ, Av. Brasil, n° 4365, Manguinhos, CEP 21045-900, Rio de Janeiro, Brazil.
| | - R X Faria
- Laboratory of Cellular Communication, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Av. Brasil, n° 4365, Manguinhos, CEP 21045-900, Rio de Janeiro, Brazil
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23
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Calcium Entry Through Thermosensory Channels. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 898:265-304. [PMID: 27161233 DOI: 10.1007/978-3-319-26974-0_12] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
ThermoTRPs are unique channels that mediate Na(+) and Ca(2+) currents in response to changes in ambient temperature. In combination with their activation by other physical and chemical stimuli, they are considered key integrators of environmental cues into neuronal excitability. Furthermore, roles of thermoTRPs in non-neuronal tissues are currently emerging such as insulin secretion in pancreatic β-cells, and links to cancer. Calcium permeability through thermoTRPs appears a central hallmark for their physiological and pathological activities. Moreover, it is currently being proposed that beyond working as a second messenger, Ca(2+) can function locally by acting on protein complexes near the membrane. Interestingly, thermoTRPs can enhance and expand the inherent plasticity of signalplexes by conferring them temperature, pH and lipid regulation through Ca(2+) signalling. Thus, unveiling the local role of Ca(2+) fluxes induced by thermoTRPs on the dynamics of membrane-attached signalling complexes as well as their significance in cellular processes, are central issues that will expand the opportunities for therapeutic intervention in disorders involving dysfunction of thermoTRP channels.
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Redmond WJ, Cawston EE, Grimsey NL, Stuart J, Edington AR, Glass M, Connor M. Identification of N-arachidonoyl dopamine as a highly biased ligand at cannabinoid CB1 receptors. Br J Pharmacol 2016; 173:115-27. [PMID: 26398720 PMCID: PMC4813372 DOI: 10.1111/bph.13341] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2014] [Revised: 09/13/2015] [Accepted: 09/17/2015] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND AND PURPOSE N-arachidonyl dopamine (NADA) has been identified as a putative endocannabinoid, but there is little information about which signalling pathways it activates. The purpose of this study was to identify the signalling pathways activated by NADA in vitro. EXPERIMENTAL APPROACH Human or rat cannabinoid CB1 receptors were expressed in AtT20, CHO or HEK 293 cells. NADA displacement of radiolabelled cannabinoids, and CB1 receptor mediated activation of K channels or ERK phosphorylation, release of intracellular calcium ([Ca]i ) and modulation of adenylyl cyclase were measured in addition to NADA effects on CB1 receptor trafficking. KEY RESULTS At concentrations up to 30 μM, NADA failed to activate any signalling pathways via CB1 receptors, with the exception of mobilization of [Ca]i . The elevations of [Ca]i were insensitive to pertussis toxin, and reduced or abolished by blockers of Gq /11 -dependent processes including U73122, thapsigargin and a peptide antagonist of Gq /11 activation. Prolonged NADA incubation produced modest loss of cell surface CB1 receptors. The prototypical cannabinoid agonist CP55940 signalled as expected in all assays. CONCLUSIONS AND IMPLICATIONS NADA is an ineffective agonist at most canonical cannabinoid receptor signalling pathways, but did promote mobilization of [Ca]i via Gq -dependent processes and some CB1 receptor trafficking. This signalling profile is distinct from that of any known cannabinoid, and suggests that NADA may have a unique spectrum of effects in vivo. Our results also indicate that it may be possible to identify highly biased CB1 receptor ligands displaying a subset of the pharmacological or therapeutic effects usually attributed to CB1 ligands.
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Affiliation(s)
- William J. Redmond
- Department of Biomedical Sciences, Faculty of Medicine and Health SciencesMacquarie UniversityNSW2109Australia
| | - Erin E. Cawston
- Department of Pharmacology and Clinical Pharmacology, and Centre for Brain ResearchUniversity of AucklandAucklandNew Zealand
| | - Natasha L. Grimsey
- Department of Pharmacology and Clinical Pharmacology, and Centre for Brain ResearchUniversity of AucklandAucklandNew Zealand
| | - Jordyn Stuart
- Department of Biomedical Sciences, Faculty of Medicine and Health SciencesMacquarie UniversityNSW2109Australia
| | - Amelia R. Edington
- Department of Biomedical Sciences, Faculty of Medicine and Health SciencesMacquarie UniversityNSW2109Australia
| | - Michelle Glass
- Department of Pharmacology and Clinical Pharmacology, and Centre for Brain ResearchUniversity of AucklandAucklandNew Zealand
| | - Mark Connor
- Department of Biomedical Sciences, Faculty of Medicine and Health SciencesMacquarie UniversityNSW2109Australia
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Rajasekhar P, Poole DP, Liedtke W, Bunnett NW, Veldhuis NA. P2Y1 Receptor Activation of the TRPV4 Ion Channel Enhances Purinergic Signaling in Satellite Glial Cells. J Biol Chem 2015; 290:29051-62. [PMID: 26475857 DOI: 10.1074/jbc.m115.689729] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2015] [Indexed: 01/07/2023] Open
Abstract
Transient receptor potential (TRP) ion channels of peripheral sensory pathways are important mediators of pain, itch, and neurogenic inflammation. They are expressed by primary sensory neurons and by glial cells in the central nervous system, but their expression and function in satellite glial cells (SGCs) of sensory ganglia have not been explored. SGCs tightly ensheath neurons of sensory ganglia and can regulate neuronal excitability in pain and inflammatory states. Using a modified dissociation protocol, we isolated neurons with attached SGCs from dorsal root ganglia of mice. SGCs, which were identified by expression of immunoreactive Kir4.1 and glutamine synthetase, were closely associated with neurons, identified using the pan-neuronal marker NeuN. A subpopulation of SGCs expressed immunoreactive TRP vanilloid 4 (TRPV4) and responded to the TRPV4-selective agonist GSK1016790A by an influx of Ca(2+) ions. SGCs did not express functional TRPV1, TRPV3, or TRP ankyrin 1 channels. Responses to GSK1016790A were abolished by the TRPV4 antagonist HC067047 and were absent in SGCs from Trpv4(-/-) mice. The P2Y1-selective agonist 2-methylthio-ADP increased [Ca(2+)]i in SGCs, and responses were prevented by the P2Y1-selective antagonist MRS2500. P2Y1 receptor-mediated responses were enhanced in TRPV4-expressing SGCs and HEK293 cells, suggesting that P2Y1 couples to and activates TRPV4. PKC inhibitors prevented P2Y1 receptor activation of TRPV4. Our results provide the first evidence for expression of TRPV4 in SGCs and demonstrate that TRPV4 is a purinergic receptor-operated channel in SGCs of sensory ganglia.
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Affiliation(s)
- Pradeep Rajasekhar
- From the Monash Institute of Pharmaceutical Sciences, Australian Research Council Centre of Excellence in Convergent Bio-Nano Science and Technology, and
| | - Daniel P Poole
- From the Monash Institute of Pharmaceutical Sciences, Australian Research Council Centre of Excellence in Convergent Bio-Nano Science and Technology, and the Departments of Anatomy and Neuroscience
| | - Wolfgang Liedtke
- the Department of Neurology, School of Medicine, Duke University, Durham, North Carolina 27710
| | - Nigel W Bunnett
- From the Monash Institute of Pharmaceutical Sciences, Australian Research Council Centre of Excellence in Convergent Bio-Nano Science and Technology, and Department of Anaesthesia and Peri-operative Medicine, Monash University, Victoria 3052, Australia, Pharmacology and Therapeutics, University of Melbourne, Parkville, Victoria 3010, Australia, and
| | - Nicholas A Veldhuis
- From the Monash Institute of Pharmaceutical Sciences, Australian Research Council Centre of Excellence in Convergent Bio-Nano Science and Technology, and Genetics, and
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Zaelzer C, Hua P, Prager-Khoutorsky M, Ciura S, Voisin D, Liedtke W, Bourque C. ΔN-TRPV1: A Molecular Co-detector of Body Temperature and Osmotic Stress. Cell Rep 2015; 13:23-30. [DOI: 10.1016/j.celrep.2015.08.061] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2014] [Revised: 07/25/2015] [Accepted: 08/21/2015] [Indexed: 10/23/2022] Open
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Polymodal Transient Receptor Potential Vanilloid (TRPV) Ion Channels in Chondrogenic Cells. Int J Mol Sci 2015; 16:18412-38. [PMID: 26262612 PMCID: PMC4581253 DOI: 10.3390/ijms160818412] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2015] [Revised: 07/03/2015] [Accepted: 07/07/2015] [Indexed: 12/17/2022] Open
Abstract
Mature and developing chondrocytes exist in a microenvironment where mechanical load, changes of temperature, osmolarity and acidic pH may influence cellular metabolism. Polymodal Transient Receptor Potential Vanilloid (TRPV) receptors are environmental sensors mediating responses through activation of linked intracellular signalling pathways. In chondrogenic high density cultures established from limb buds of chicken and mouse embryos, we identified TRPV1, TRPV2, TRPV3, TRPV4 and TRPV6 mRNA expression with RT-PCR. In both cultures, a switch in the expression pattern of TRPVs was observed during cartilage formation. The inhibition of TRPVs with the non-selective calcium channel blocker ruthenium red diminished chondrogenesis and caused significant inhibition of proliferation. Incubating cell cultures at 41 °C elevated the expression of TRPV1, and increased cartilage matrix production. When chondrogenic cells were exposed to mechanical load at the time of their differentiation into matrix producing chondrocytes, we detected increased mRNA levels of TRPV3. Our results demonstrate that developing chondrocytes express a full palette of TRPV channels and the switch in the expression pattern suggests differentiation stage-dependent roles of TRPVs during cartilage formation. As TRPV1 and TRPV3 expression was altered by thermal and mechanical stimuli, respectively, these are candidate channels that contribute to the transduction of environmental stimuli in chondrogenic cells.
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Miyano K, Minami K, Yokoyama T, Ohbuchi K, Yamaguchi T, Murakami S, Shiraishi S, Yamamoto M, Matoba M, Uezono Y. Tramadol and its metabolite m1 selectively suppress transient receptor potential ankyrin 1 activity, but not transient receptor potential vanilloid 1 activity. Anesth Analg 2015; 120:790-8. [PMID: 25642661 DOI: 10.1213/ane.0000000000000625] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
BACKGROUND The transient receptor potential vanilloid 1 (TRPV1) and the transient receptor potential ankyrin 1 (TRPA1), which are expressed in sensory neurons, are polymodal nonselective cation channels that sense noxious stimuli. Recent reports showed that these channels play important roles in inflammatory, neuropathic, or cancer pain, suggesting that they may serve as attractive analgesic pharmacological targets. Tramadol is an effective analgesic that is widely used in clinical practice. Reportedly, tramadol and its metabolite (M1) bind to μ-opioid receptors and/or inhibit reuptake of monoamines in the central nervous system, resulting in the activation of the descending inhibitory system. However, the fundamental mechanisms of tramadol in pain control remain unclear. TRPV1 and TRPA1 may be targets of tramadol; however, they have not been studied extensively. METHODS We examined whether and how tramadol and M1 act on human embryonic kidney 293 (HEK293) cells expressing human TRPV1 (hTRPV1) or hTRPA1 by using a Ca imaging assay and whole-cell patch-clamp recording. RESULTS Tramadol and M1 (0.01-10 μM) alone did not increase in intracellular Ca concentration ([Ca]i) in HEK293 cells expressing hTRPV1 or hTRPA1 compared with capsaicin (a TRPV1 agonist) or the allyl isothiocyanate (AITC, a TRPA1 agonist), respectively. Furthermore, in HEK293 cells expressing hTRPV1, pretreatment with tramadol or M1 for 5 minutes did not change the increase in [Ca]i induced by capsaicin. Conversely, pretreatment with tramadol (0.1-10 μM) and M1 (1-10 μM) significantly suppressed the AITC-induced [Ca]i increases in HEK293 cells expressing hTRPA1. In addition, the patch-clamp study showed that pretreatment with tramadol and M1 (10 μM) decreased the inward currents induced by AITC. CONCLUSIONS These data indicate that tramadol and M1 selectively inhibit the function of hTRPA1, but not that of hTRPV1, and that hTRPA1 may play a role in the analgesic effects of these compounds.
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Affiliation(s)
- Kanako Miyano
- From the *Division of Cancer Pathophysiology, National Cancer Center Research Institute, Chuo-ku, Tokyo, Japan; †Department of Anesthesiology and Critical Care Medicine, Jichi Medical University, Shimotsuke, Tochigi, Japan; ‡Tsumura Research Labs, Tumura & Co., Inashiki-gun, Ibaraki, Japan; §Division of Biostatistics, Tohoku University Graduate School of Medicine, Clinical Research Data Center, Tohoku University Hospital, Sendai, Miyagi, Japan; ∥Department of Palliative Medicine, Seirei Sakura Citizen Hospital, Sakura-shi, Chiba, Japan; and ¶Department of Palliative Medicine, Aomori Prefectural Central Hospital, Aomori-city, Aomori, Japan
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Grace MS, Lieu T, Darby B, Abogadie FC, Veldhuis N, Bunnett NW, McIntyre P. The tyrosine kinase inhibitor bafetinib inhibits PAR2-induced activation of TRPV4 channels in vitro and pain in vivo. Br J Pharmacol 2015; 171:3881-94. [PMID: 24779362 DOI: 10.1111/bph.12750] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2014] [Revised: 04/02/2014] [Accepted: 04/17/2014] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND AND PURPOSE Protease-activated receptor 2 (PAR2) is expressed on nociceptive neurons, and can sensitize transient receptor potential (TRP) ion channels to amplify neurogenic inflammation and pain. The mechanisms by which this occurs are not fully understood. PAR2 causes receptor-operated activation of TRPV4 channels and TRPV4 null mice have attenuated PAR2-stimulated neurogenic inflammation and mechanical hyperalgesia. Here we investigate the intracellular signalling mechanisms underlying PAR2-induced TRPV4 channel activation and pain. EXPERIMENTAL APPROACH Responses of non-transfected and TRPV4-transfected HEK293 cells to agonists of PAR2 (trypsin and SLIGRL) and TRPV4 channels (GSK1016790A) were determined using calcium imaging. Inhibitors of TRPV4 channels (HC067047), sarcoendoplasmic reticulum calcium transport ATPase (thapsigargin), Gαq (UBO-QIC), tyrosine kinases (bafetinib and dasatinib) or PI3 kinases (wortmannin and LY294002) were used to investigate signalling mechanisms. In vivo effects of tyrosine kinase inhibitors on PAR2 -induced mechanical hyperalgesia were assessed in mice. KEY RESULTS In non-transfected HEK293 cells, PAR2 activation transiently increased intracellular calcium ([Ca(2+) ]i ). Functional expression of TRPV4 channels caused a sustained increase of [Ca(2+) ]i , inhibited by HC067047, bafetinib and wortmannin; but not by thapsigargin, UBO-QIC, dasatinib or LY294002. Bafetinib but not dasatinib inhibited PAR2-induced mechanical hyperalgesia in vivo. CONCLUSIONS AND IMPLICATIONS This study supports a role for tyrosine kinases in PAR2-mediated receptor-operated gating of TRPV4 channels, independent of Gαq stimulation. The ability of a tyrosine kinase inhibitor to diminish PAR2-induced activation of TRPV4 channels and consequent mechanical hyperalgesia identifies bafetinib (which is in development in oncology) as a potential novel analgesic therapy.
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Affiliation(s)
- M S Grace
- School of Medical Sciences and Health Innovations Research Institute, RMIT University, Bundoora, VIC, Australia
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Octylphenol induces changes in glycosylation pattern, calcium level and ultrastructure of bank vole spermatozoa in vitro. Toxicol In Vitro 2015; 29:529-37. [DOI: 10.1016/j.tiv.2014.12.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2014] [Revised: 09/26/2014] [Accepted: 12/18/2014] [Indexed: 11/17/2022]
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Munns CH, Chung MK, Sanchez YE, Amzel LM, Caterina MJ. Role of the outer pore domain in transient receptor potential vanilloid 1 dynamic permeability to large cations. J Biol Chem 2015; 290:5707-24. [PMID: 25568328 DOI: 10.1074/jbc.m114.597435] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Transient receptor potential vanilloid 1 (TRPV1) has been shown to alter its ionic selectivity profile in a time- and agonist-dependent manner. One hallmark of this dynamic process is an increased permeability to large cations such as N-methyl-D-glucamine (NMDG). In this study, we mutated residues throughout the TRPV1 pore domain to identify loci that contribute to dynamic large cation permeability. Using resiniferatoxin (RTX) as the agonist, we identified multiple gain-of-function substitutions within the TRPV1 pore turret (N628P and S629A), pore helix (F638A), and selectivity filter (M644A) domains. In all of these mutants, maximum NMDG permeability was substantially greater than that recorded in wild type TRPV1, despite similar or even reduced sodium current density. Two additional mutants, located in the pore turret (G618W) and selectivity filter (M644I), resulted in significantly reduced maximum NMDG permeability. M644A and M644I also showed increased and decreased minimum NMDG permeability, respectively. The phenotypes of this panel of mutants were confirmed by imaging the RTX-evoked uptake of the large cationic fluorescent dye YO-PRO1. Whereas none of the mutations selectively altered capsaicin-induced changes in NMDG permeability, the loss-of-function phenotypes seen with RTX stimulation of G618W and M644I were recapitulated in the capsaicin-evoked YO-PRO1 uptake assay. Curiously, the M644A substitution resulted in a loss, rather than a gain, in capsaicin-evoked YO-PRO1 uptake. Modeling of our mutations onto the recently determined TRPV1 structure revealed several plausible mechanisms for the phenotypes observed. We conclude that side chain interactions at a few specific loci within the TRPV1 pore contribute to the dynamic process of ionic selectivity.
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Affiliation(s)
- Clare H Munns
- From the Departments of Neurosurgery, Biological Chemistry, and Neuroscience, Neurosurgery Pain Research Institute, and Center for Sensory Biology and
| | - Man-Kyo Chung
- the Department of Neural and Pain Sciences, University of Maryland School of Dentistry, Baltimore, Maryland 21201
| | - Yuly E Sanchez
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins School of Medicine, Baltimore, Maryland 21205, the Departamento de Física, Facultad de Ciencias, Universidad Nacional de Colombia, 111321 Bogotá, D.C., Colombia, and the Departamento de Nutrición y Bioquímica, Facultad de Ciencias, Pontificia Universidad Javeriana, 110231 Bogotá, D.C., Colombia
| | - L Mario Amzel
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins School of Medicine, Baltimore, Maryland 21205
| | - Michael J Caterina
- From the Departments of Neurosurgery, Biological Chemistry, and Neuroscience, Neurosurgery Pain Research Institute, and Center for Sensory Biology and
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Nilius B, Szallasi A. Transient Receptor Potential Channels as Drug Targets: From the Science of Basic Research to the Art of Medicine. Pharmacol Rev 2014; 66:676-814. [DOI: 10.1124/pr.113.008268] [Citation(s) in RCA: 348] [Impact Index Per Article: 34.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
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Hofherr A, Wagner C, Fedeles S, Somlo S, Köttgen M. N-glycosylation determines the abundance of the transient receptor potential channel TRPP2. J Biol Chem 2014; 289:14854-67. [PMID: 24719335 DOI: 10.1074/jbc.m114.562264] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Glycosylation plays a critical role in the biogenesis and function of membrane proteins. Transient receptor potential channel TRPP2 is a nonselective cation channel that is mutated in autosomal dominant polycystic kidney disease. TRPP2 has been shown to be heavily N-glycosylated, but the glycosylation sites and the biological role of N-linked glycosylation have not been investigated. Here we show, using a combination of mass spectrometry and biochemical approaches, that native TRPP2 is glycosylated at five asparagines in the first extracellular loop. Glycosylation is required for the efficient biogenesis of TRPP2 because mutations of the glycosylated asparagines result in strongly decreased protein expression of the ion channel. Wild-type and N-glycosylation-deficient TRPP2 is degraded in lysosomes, as shown by increased TRPP2 protein levels upon chemical inhibition of lysosomal degradation. In addition, using pharmacological and genetic approaches, we demonstrate that glucosidase II (GII) mediates glycan trimming of TRPP2. The non-catalytic β subunit of glucosidase II (GIIβ) is encoded by PRKCSH, one of the genes causing autosomal dominant polycystic liver disease (ADPLD). The impaired GIIβ-dependent glucose trimming of TRPP2 glycosylation in ADPLD may explain the decreased TRPP2 protein expression in Prkcsh(-/-) mice and the genetic interaction observed between TRPP2 and PRKCSH in ADPLD. These results highlight the biological importance of N-linked glycosylation and GII-mediated glycan trimming in the control of biogenesis and stability of TRPP2.
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Affiliation(s)
- Alexis Hofherr
- From the Renal Division, Department of Medicine, University Medical Center Freiburg, Hugstetter Straβe 55, 79106 Freiburg, Germany, the Spemann Graduate School of Biology and Medicine (SGBM) and Faculty of Biology, Albert-Ludwigs-University Freiburg, 79106 Freiburg, Germany, and
| | - Claudius Wagner
- From the Renal Division, Department of Medicine, University Medical Center Freiburg, Hugstetter Straβe 55, 79106 Freiburg, Germany
| | - Sorin Fedeles
- the Departments of Medicine and Genetics, Yale University School of Medicine, New Haven, Connecticut 06520
| | - Stefan Somlo
- the Departments of Medicine and Genetics, Yale University School of Medicine, New Haven, Connecticut 06520
| | - Michael Köttgen
- From the Renal Division, Department of Medicine, University Medical Center Freiburg, Hugstetter Straβe 55, 79106 Freiburg, Germany,
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Syam N, Rougier JS, Abriel H. Glycosylation of TRPM4 and TRPM5 channels: molecular determinants and functional aspects. Front Cell Neurosci 2014; 8:52. [PMID: 24605085 PMCID: PMC3932411 DOI: 10.3389/fncel.2014.00052] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2013] [Accepted: 02/06/2014] [Indexed: 11/30/2022] Open
Abstract
The transient receptor potential channel, TRPM4, and its closest homolog, TRPM5, are non-selective cation channels that are activated by an increase in intracellular calcium. They are expressed in many cell types, including neurons and myocytes. Although the electrophysiological and pharmacological properties of these two channels have been previously studied, less is known about their regulation, in particular their post-translational modifications. We, and others, have reported that wild-type (WT) TRPM4 channels expressed in HEK293 cells, migrated on SDS-PAGE gel as doublets, similar to other ion channels and membrane proteins. In the present study, we provide evidence that TRPM4 and TRPM5 are each N-linked glycosylated at a unique residue, Asn992 and Asn932, respectively. N-linked glycosylated TRPM4 is also found in native cardiac cells. Biochemical experiments using HEK293 cells over-expressing WT TRPM4/5 or N992Q/N932Q mutants demonstrated that the abolishment of N-linked glycosylation did not alter the number of channels at the plasma membrane. In parallel, electrophysiological experiments demonstrated a decrease in the current density of both mutant channels, as compared to their respective controls, either due to the Asn to Gln mutations themselves or abolition of glycosylation. To discriminate between these possibilities, HEK293 cells expressing TRPM4 WT were treated with tunicamycin, an inhibitor of glycosylation. In contrast to N-glycosylation signal abolishment by mutagenesis, tunicamycin treatment led to an increase in the TRPM4-mediated current. Altogether, these results demonstrate that TRPM4 and TRPM5 are both N-linked glycosylated at a unique site and also suggest that TRPM4/5 glycosylation seems not to be involved in channel trafficking, but mainly in their functional regulation.
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Affiliation(s)
- Ninda Syam
- Department of Clinical Research, and Swiss National Centre of Competence in Research (NCCR) TransCure, University of Bern Bern, Switzerland
| | - Jean-Sébastien Rougier
- Department of Clinical Research, and Swiss National Centre of Competence in Research (NCCR) TransCure, University of Bern Bern, Switzerland
| | - Hugues Abriel
- Department of Clinical Research, and Swiss National Centre of Competence in Research (NCCR) TransCure, University of Bern Bern, Switzerland
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Scott H, Panin VM. N-glycosylation in regulation of the nervous system. ADVANCES IN NEUROBIOLOGY 2014; 9:367-94. [PMID: 25151388 DOI: 10.1007/978-1-4939-1154-7_17] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Protein N-glycosylation can influence the nervous system in a variety of ways by affecting functions of glycoproteins involved in nervous system development and physiology. The importance of N-glycans for different aspects of neural development has been well documented. For example, some N-linked carbohydrate structures were found to play key roles in neural cell adhesion and axonal targeting during development. At the same time, the involvement of glycosylation in the regulation of neural physiology remains less understood. Recent studies have implicated N-glycosylation in the regulation of neural transmission, revealing novel roles of glycans in synaptic processes and the control of neural excitability. N-Glycans were found to markedly affect the function of several types of synaptic proteins involved in key steps of synaptic transmission, including neurotransmitter release, reception, and uptake. Glycosylation also regulates a number of channel proteins, such as TRP channels that control responses to environmental stimuli and voltage-gated ion channels, the principal determinants of neuronal excitability. Sialylated carbohydrate structures play a particularly prominent part in the modulation of voltage-gated ion channels. Sialic acids appear to affect channel functions via several mechanisms, including charge interactions, as well as other interactions that probably engage steric effects and interactions with other molecules. Experiments also indicated that some structural features of glycans can be particularly important for their function. Since glycan structures can vary significantly between different cell types and depend on the metabolic state of the cell, it is important to analyze glycan functions using in vivo approaches. While the complexity of the nervous system and intricacies of glycosylation pathways can create serious obstacles for in vivo experiments in vertebrates, recent studies have indicated that more simple and experimentally tractable model organisms like Drosophila should provide important advantages for elucidating evolutionarily conserved functions of N-glycosylation in the nervous system.
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Affiliation(s)
- Hilary Scott
- Department of Biochemistry and Biophysics, Texas A&M University, 2128 TAMU, College Station, TX, 77843, USA
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Singh U, Bernstein JA. Intranasal Capsaicin in Management of Nonallergic (Vasomotor) Rhinitis. CAPSAICIN AS A THERAPEUTIC MOLECULE 2014; 68:147-70. [PMID: 24941668 DOI: 10.1007/978-3-0348-0828-6_6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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Nagy I, Friston D, Valente JS, Torres Perez JV, Andreou AP. Pharmacology of the capsaicin receptor, transient receptor potential vanilloid type-1 ion channel. PROGRESS IN DRUG RESEARCH. FORTSCHRITTE DER ARZNEIMITTELFORSCHUNG. PROGRES DES RECHERCHES PHARMACEUTIQUES 2014; 68:39-76. [PMID: 24941664 DOI: 10.1007/978-3-0348-0828-6_2] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The capsaicin receptor, transient receptor potential vanilloid type 1 ion channel (TRPV1), has been identified as a polymodal transducer molecule on a sub-set of primary sensory neurons which responds to various stimuli including noxious heat (> -42 degrees C), protons and vanilloids such as capsaicin, the hot ingredient of chilli peppers. Subsequently, TRPV1 has been found indispensable for the development of burning pain and reflex hyperactivity associated with inflammation of peripheral tissues and viscera, respectively. Therefore, TRPV1 is regarded as a major target for the development of novel agents for the control of pain and visceral hyperreflexia in inflammatory conditions. Initial efforts to introduce agents acting on TRPV1 into clinics have been hampered by unexpected side-effects due to wider than expected expression in various tissues, as well as by the complex pharmacology, of TRPV1. However, it is believed that better understanding of the pharmacological properties of TRPV1 and specific targeting of tissues may eventually lead to the development of clinically useful agents. In order to assist better understanding of TRPV1 pharmacology, here we are giving a comprehensive account on the activation and inactivation mechanisms and the structure-function relationship of TRPV1.
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Klöckner U, Rueckschloss U, Grossmann C, Matzat S, Schumann K, Ebelt H, Müller-Werdan U, Loppnow H, Werdan K, Gekle M. Inhibition of cardiac pacemaker channel hHCN2 depends on intercalation of lipopolysaccharide into channel-containing membrane microdomains. J Physiol 2013; 592:1199-211. [PMID: 24366264 DOI: 10.1113/jphysiol.2013.268540] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Depressed heart rate variability in severe inflammatory diseases can be partially explained by the lipopolysaccharide (LPS)-dependent modulation of cardiac pacemaker channels. Recently, we showed that LPS inhibits pacemaker current in sinoatrial node cells and in HEK293 cells expressing cloned pacemaker channels, respectively. The present study was designed to verify whether this inhibition involves LPS-dependent intracellular signalling and to identify structures of LPS responsible for pacemaker current modulation. We examined the effect of LPS on the activity of human hyperpolarization-activated cyclic nucleotide-gated channel 2 (hHCN2) stably expressed in HEK293 cells. In whole-cell recordings, bath application of LPS decreased pacemaker current (IhHCN2) amplitude. The same protocol had no effect on channel activity in cell-attached patch recordings, in which channels are protected from the LPS-containing bath solution. This demonstrates that LPS must interact directly with or close to the channel protein. After cleavage of LPS into lipid A and the polysaccharide chain, neither of them alone impaired IhHCN2, which suggests that modulation of channel activity critically depends on the integrity of the entire LPS molecule. We furthermore showed that β-cyclodextrin interfered with LPS-dependent channel modulation predominantly via scavenging of lipid A, thereby abrogating the capability of LPS to intercalate into target cell membranes. We conclude that LPS impairs IhHCN2 by a local mechanism that is restricted to the vicinity of the channels. Furthermore, intercalation of lipid A into target cell membranes is a prerequisite for the inhibition that is suggested to depend on the direct interaction of the LPS polysaccharide chain with cardiac pacemaker channels.
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Affiliation(s)
- Udo Klöckner
- Julius Bernstein Institut für Physiologie, Martin Luther Universität Halle-Wittenberg, Magdeburger Strasse 6, 06112 Halle (Saale), Germany.
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Woo SK, Kwon MS, Ivanov A, Geng Z, Gerzanich V, Simard JM. Complex N-glycosylation stabilizes surface expression of transient receptor potential melastatin 4b protein. J Biol Chem 2013; 288:36409-17. [PMID: 24214984 DOI: 10.1074/jbc.m113.530584] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
N-glycosylation is important for the function and regulation of ion channels. We examined the role of N-glycosylation of transient receptor potential melastatin (Trpm) 4b, a membrane glycoprotein that regulates calcium influx. Trpm4b was expressed in vivo in all rat tissues examined. In each tissue, Trpm4b had a different molecular mass, between ∼129 and ∼141 kDa, but all reverted to ∼120 kDa following treatment with peptide:N-glycosidase F, consistent with N-glycosylation being the principal form of post-translational modification of Trpm4b in vivo. In six stable isogenic cell lines that express different levels of Trpm4b, two forms were found, high mannose, core-glycosylated and complex, highly glycosylated (HG), with HG-Trpm4b comprising 85% of the total Trpm4b expressed. For both forms, surface expression was directly proportional to the total Trpm4b expressed. Complex N-glycosylation doubled the percentage of Trpm4b at the surface, compared with high mannose N-glycosylation. Mutation of the single N-glycosylation consensus sequence at Asn-988 (Trpm4b-N988Q), located near the pore-forming loop between transmembrane helices 5 and 6, prevented glycosylation, but did not prevent surface expression, impair formation of functional membrane channels, or alter channel conductance. In transfection experiments, the time courses for appearance of HG-Trpm4b and Trpm4b-N988Q on the surface were similar. In experiments with cycloheximide inhibition of protein synthesis, the time course for disappearance of HG-Trpm4b from the surface was much slower than that for Trpm4b-N988Q. We conclude that N-glycosylation is not required for surface expression or channel function, but that complex N-glycosylation plays a crucial role in stabilizing surface expression of Trpm4b.
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Knapman A, Abogadie F, McIntrye P, Connor M. A real-time, fluorescence-based assay for measuring μ-opioid receptor modulation of adenylyl cyclase activity in Chinese hamster ovary cells. ACTA ACUST UNITED AC 2013; 19:223-31. [PMID: 23989451 DOI: 10.1177/1087057113501391] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Inhibition of adenylyl cyclase (AC) activity is frequently used to measure µ-opioid receptor (MOR) activation. We sought to develop a simple, rapid assay of AC activity in whole cells that could be used to study MOR signaling. Chinese hamster ovary cells expressing human MOR (CHO-MOR cells) were grown in 96-well plates and loaded with membrane potential-sensitive fluorescent dye. CHO-MOR cells were treated with the AC activator forskolin (FSK), with or without simultaneous application of MOR agonists, and the resulting change in fluorescence was measured. CHO-MOR cells hyperpolarized in response to application of FSK (pEC₅₀, 7.3) or calcitonin (pEC₅₀, 9.4). A submaximally effective concentration of FSK (300 nM) caused a 52% ± 2% decrease in fluorescence. Simultaneous application of the opioids DAMGO (pEC₅₀, 7.4; E(max), 56%), morphine (pEC₅₀, 7.0; E(max), 61%); and buprenorphine (pEC₅₀, 8.6; E(max), 24%) inhibited the FSK response in a dose-dependent manner while having no effect by themselves. The effects of DAMGO were blocked by pertussis toxin. This assay represents a simple, robust method for real-time observation of AC inhibition by MOR in CHO cells. It represents an appealing alternative to end-point assays that rely on cAMP accumulation and can avoid potential confounds associated with rapid desensitization of MOR signaling.
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Affiliation(s)
- Alisa Knapman
- 1Australian School of Advanced Medicine, Macquarie University, NSW Australia
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42
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Dreses-Werringloer U, Vingtdeux V, Zhao H, Chandakkar P, Davies P, Marambaud P. CALHM1 controls the Ca²⁺-dependent MEK, ERK, RSK and MSK signaling cascade in neurons. J Cell Sci 2013; 126:1199-206. [PMID: 23345406 DOI: 10.1242/jcs.117135] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Calcium homeostasis modulator 1 (CALHM1) is a Ca(2+) channel controlling neuronal excitability and potentially involved in the pathogenesis of Alzheimer's disease (AD). Although strong evidence indicates that CALHM1 is required for neuronal electrical activity, its role in intracellular Ca(2+) signaling remains unknown. In the present study, we show that in hippocampal HT-22 cells, CALHM1 expression led to a robust and relatively selective activation of the Ca(2+)-sensing kinases ERK1/2. CALHM1 also triggered activation of MEK1/2, the upstream ERK1/2-activating kinases, and of RSK1/2/3 and MSK1, two downstream effectors of ERK1/2 signaling. CALHM1-mediated activation of ERK1/2 signaling was controlled by the small GTPase Ras. Pharmacological inhibition of CALHM1 permeability using Ruthenium Red, Zn(2+), and Gd(3+), or expression of the CALHM1 N140A and W114A mutants, which are deficient in mediating Ca(2+) influx, prevented the effect of CALHM1 on the MEK, ERK, RSK and MSK signaling cascade, demonstrating that CALHM1 controlled this pathway via its channel properties. Importantly, expression of CALHM1 bearing the natural P86L polymorphism, which leads to a partial loss of CALHM1 function and is associated with an earlier age at onset in AD patients, showed reduced activation of ERK1/2, RSK1/2/3, and MSK1. In line with these results obtained in transfected cells, primary cerebral neurons isolated from Calhm1 knockout mice showed significant impairments in the activation of MEK, ERK, RSK and MSK signaling. The present study identifies a previously uncharacterized mechanism of control of Ca(2+)-dependent ERK1/2 signaling in neurons, and further establishes CALHM1 as a critical ion channel for neuronal signaling and function.
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Affiliation(s)
- Ute Dreses-Werringloer
- Litwin-Zucker Research Center for the Study of Alzheimer's Disease, The Feinstein Institute for Medical Research, Manhasset, New York, USA
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43
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Poole DP, Amadesi S, Veldhuis NA, Abogadie FC, Lieu T, Darby W, Liedtke W, Lew MJ, McIntyre P, Bunnett NW. Protease-activated receptor 2 (PAR2) protein and transient receptor potential vanilloid 4 (TRPV4) protein coupling is required for sustained inflammatory signaling. J Biol Chem 2013; 288:5790-802. [PMID: 23288842 DOI: 10.1074/jbc.m112.438184] [Citation(s) in RCA: 116] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
G protein-coupled receptors of nociceptive neurons can sensitize transient receptor potential (TRP) ion channels, which amplify neurogenic inflammation and pain. Protease-activated receptor 2 (PAR(2)), a receptor for inflammatory proteases, is a major mediator of neurogenic inflammation and pain. We investigated the signaling mechanisms by which PAR(2) regulates TRPV4 and determined the importance of tyrosine phosphorylation in this process. Human TRPV4 was expressed in HEK293 cells under control of a tetracycline-inducible promoter, allowing controlled and graded channel expression. In cells lacking TRPV4, the PAR(2) agonist stimulated a transient increase in [Ca(2+)](i). TRPV4 expression led to a markedly sustained increase in [Ca(2+)](i). Removal of extracellular Ca(2+) and treatment with the TRPV4 antagonists Ruthenium Red or HC067047 prevented the sustained response. Inhibitors of phospholipase A(2) and cytochrome P450 epoxygenase attenuated the sustained response, suggesting that PAR(2) generates arachidonic acid-derived lipid mediators, such as 5',6'-EET, that activate TRPV4. Src inhibitor 1 suppressed PAR(2)-induced activation of TRPV4, indicating the importance of tyrosine phosphorylation. The TRPV4 tyrosine mutants Y110F, Y805F, and Y110F/Y805F were expressed normally at the cell surface. However, PAR(2) was unable to activate TRPV4 with the Y110F mutation. TRPV4 antagonism suppressed PAR(2) signaling to primary nociceptive neurons, and TRPV4 deletion attenuated PAR(2)-stimulated neurogenic inflammation. Thus, PAR(2) activation generates a signal that induces sustained activation of TRPV4, which requires a key tyrosine residue (TRPV4-Tyr-110). This mechanism partly mediates the proinflammatory actions of PAR(2).
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Affiliation(s)
- Daniel P Poole
- Monash Institute of Pharmaceutical Sciences, Parkville, Victoria 3052, Australia
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