1
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Genovese M, Galietta LJV. Anoctamin pharmacology. Cell Calcium 2024; 121:102905. [PMID: 38788257 DOI: 10.1016/j.ceca.2024.102905] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2024] [Revised: 05/07/2024] [Accepted: 05/09/2024] [Indexed: 05/26/2024]
Abstract
TMEM16 proteins, also known as anoctamins, are a family of ten membrane proteins with various tissue expression and subcellular localization. TMEM16A (anoctamin 1) is a plasma membrane protein that acts as a calcium-activated chloride channel. It is expressed in many types of epithelial cells, smooth muscle cells and some neurons. In airway epithelial cells, TMEM16A expression is particularly enhanced by inflammatory stimuli that also promote goblet cell metaplasia and mucus hypersecretion. Therefore, pharmacological modulation of TMEM16A could be beneficial to improve mucociliary clearance in chronic obstructive respiratory diseases. However, the correct approach to modulate TMEM16A activity (activation or inhibition) is still debated. Pharmacological inhibitors of TMEM16A could also be useful as anti-hypertensive agents given the TMEM16A role in smooth muscle contraction. In contrast to TMEM16A, TMEM16F (anoctamin 6) behaves as a calcium-activated phospholipid scramblase, responsible for the externalization of phosphatidylserine on cell surface. Inhibitors of TMEM16F could be useful as anti-coagulants and anti-viral agents. The role of other anoctamins as therapeutic targets is still unclear since their physiological role is still to be defined.
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Affiliation(s)
- Michele Genovese
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli (NA), Italy
| | - Luis J V Galietta
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli (NA), Italy; Department of Translational Medical Sciences (DISMET), University of Naples "Federico II", Italy.
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2
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Kim H, Shim WS, Oh U. Anoctamin 1, a multi-modal player in pain and itch. Cell Calcium 2024; 123:102924. [PMID: 38964236 DOI: 10.1016/j.ceca.2024.102924] [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: 03/04/2024] [Revised: 06/05/2024] [Accepted: 06/13/2024] [Indexed: 07/06/2024]
Abstract
Anoctamin 1 (ANO1/TMEM16A) encodes a Ca2+-activated Cl- channel. Among ANO1's many physiological functions, it plays a significant role in mediating nociception and itch. ANO1 is activated by intracellular Ca2+ and depolarization. Additionally, ANO1 is activated by heat above 44 °C, suggesting heat as another activation stimulus. ANO1 is highly expressed in nociceptors, indicating a role in nociception. Conditional Ano1 ablation in dorsal root ganglion (DRG) neurons results in a reduction in acute thermal pain, as well as thermal and mechanical allodynia or hyperalgesia evoked by inflammation or nerve injury. Pharmacological interventions also lead to a reduction in nocifensive behaviors. ANO1 is functionally linked to the bradykinin receptor and TRPV1. Bradykinin stimulates ANO1 via IP3-mediated Ca2+ release from intracellular stores, whereas TRPV1 stimulates ANO1 via a combination of Ca2+ influx and release. Nerve injury causes upregulation of ANO1 expression in DRG neurons, which is blocked by ANO1 antagonists. Due to its role in nociception, strong and specific ANO1 antagonists have been developed. ANO1 is also expressed in pruritoceptors, mediating Mas-related G protein-coupled receptors (Mrgprs)-dependent itch. The activation of ANO1 leads to chloride efflux and depolarization due to high intracellular chloride concentrations, causing pain and itch. Thus, ANO1 could be a potential target for the development of new drugs treating pain and itch.
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Affiliation(s)
- Hyungsup Kim
- Department of Biotechnology, College of Engineering, The University of Suwon, Hwaseong, 18323, Republic of Korea
| | - Won-Sik Shim
- College of Pharmacy, Gachon University, Incheon 21936, Republic of Korea
| | - Uhtaek Oh
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea; Department of Molecular Medicine and Biopharmaceutical Sciences, Graduate School of Convergence Science and Technology, Seoul National University, Seoul 08826, Republic of Korea.
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3
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Arreola J, Pérez-Cornejo P, Segura-Covarrubias G, Corral-Fernández N, León-Aparicio D, Guzmán-Hernández ML. Function and Regulation of the Calcium-Activated Chloride Channel Anoctamin 1 (TMEM16A). Handb Exp Pharmacol 2024; 283:101-151. [PMID: 35768554 DOI: 10.1007/164_2022_592] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Various human tissues express the calcium-activated chloride channel Anoctamin 1 (ANO1), also known as TMEM16A. ANO1 allows the passive chloride flux that controls different physiological functions ranging from muscle contraction, fluid and hormone secretion, gastrointestinal motility, and electrical excitability. Overexpression of ANO1 is associated with pathological conditions such as hypertension and cancer. The molecular cloning of ANO1 has led to a surge in structural, functional, and physiological studies of the channel in several tissues. ANO1 is a homodimer channel harboring two pores - one in each monomer - that work independently. Each pore is activated by voltage-dependent binding of two intracellular calcium ions to a high-affinity-binding site. In addition, the binding of phosphatidylinositol 4,5-bisphosphate to sites scattered throughout the cytosolic side of the protein aids the calcium activation process. Furthermore, many pharmacological studies have established ANO1 as a target of promising compounds that could treat several illnesses. This chapter describes our current understanding of the physiological roles of ANO1 and its regulation under physiological conditions as well as new pharmacological compounds with potential therapeutic applications.
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Affiliation(s)
- Jorge Arreola
- Physics Institute, Universidad Autónoma de San Luis Potosí, San Luis Potosí, Mexico.
| | - Patricia Pérez-Cornejo
- Department of Physiology and Biophysics, School of Medicine of Universidad Autónoma de San Luis Potosí, San Luis Potosí, Mexico
| | - Guadalupe Segura-Covarrubias
- Physics Institute, Universidad Autónoma de San Luis Potosí, San Luis Potosí, Mexico
- Department of Physiology and Biophysics, Case Western Reserve University, Cleveland, OH, USA
| | - Nancy Corral-Fernández
- Department of Physiology and Biophysics, School of Medicine of Universidad Autónoma de San Luis Potosí, San Luis Potosí, Mexico
| | - Daniel León-Aparicio
- Physics Institute, Universidad Autónoma de San Luis Potosí, San Luis Potosí, Mexico
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4
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Al-Hosni R, Ilkan Z, Agostinelli E, Tammaro P. The pharmacology of the TMEM16A channel: therapeutic opportunities. Trends Pharmacol Sci 2022; 43:712-725. [PMID: 35811176 DOI: 10.1016/j.tips.2022.06.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Revised: 06/06/2022] [Accepted: 06/08/2022] [Indexed: 12/15/2022]
Abstract
The TMEM16A Ca2+-gated Cl- channel is involved in a variety of vital physiological functions and may be targeted pharmacologically for therapeutic benefit in diseases such as hypertension, stroke, and cystic fibrosis (CF). The determination of the TMEM16A structure and high-throughput screening efforts, alongside ex vivo and in vivo animal studies and clinical investigations, are hastening our understanding of the physiology and pharmacology of this channel. Here, we offer a critical analysis of recent developments in TMEM16A pharmacology and reflect on the therapeutic opportunities provided by this target.
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Affiliation(s)
- Rumaitha Al-Hosni
- Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, UK
| | - Zeki Ilkan
- Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, UK
| | - Emilio Agostinelli
- Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, UK
| | - Paolo Tammaro
- Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, UK.
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5
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Fujii N, Amano T, Kenny GP, Mündel T, Lei TH, Honda Y, Kondo N, Nishiyasu T. TMEM16A blockers T16Ainh-A01 and benzbromarone do not modulate the regulation of sweating and cutaneous vasodilatation in humans in vivo. Exp Physiol 2022; 107:844-853. [PMID: 35688020 DOI: 10.1113/ep090521] [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: 04/19/2022] [Accepted: 06/07/2022] [Indexed: 11/08/2022]
Abstract
NEW FINDINGS What is the central question of this study? Do transmembrane member 16A (TMEM16A) blockers modulate the activation of heat loss responses of sweating and cutaneous vasodilatation? What are the main finding and its importance? Relative to the vehicle control site, TMEM16A blockers T16Ainh-A01 and benzbromarone had no effect on sweat rate or cutaneous vascular conductance during whole-body heating inducing a 1.1 ± 0.1°C increase in core temperature above baseline resting levels. These results suggest that TMEM16A blockers T16Ainh-A01 and benzbromarone do not modulate the regulation of sweating and cutaneous vasodilatation during whole-body heat stress. ABSTRACT Animal and in vitro studies suggest that transmembrane member 16A (TMEM16A), a Ca2+ -activated Cl- channel, contributes to regulating eccrine sweating. However, direct evidence supporting this possibility in humans is lacking. We assessed the hypothesis that TMEM16A blockers attenuate sweating during whole-body heating in humans. Additionally, we assessed the associated changes in the heat loss response of cutaneous vasodilatation to determine if a functional role of TMEM16A may exist. Twelve young (24 ± 2 years) adults (six females) underwent whole-body heating using a water-perfused suit to raise core temperature 1.1 ± 0.1°C above baseline. Sweat rate and cutaneous vascular conductance (normalized to maximal conductance via administration of sodium nitroprusside) were evaluated continuously at four forearm skin sites treated continuously by intradermal microdialysis with (1) lactated Ringer's solution (control), (2) 5% dimethyl sulfoxide (DMSO) serving as a vehicle control, or (3) TMEM16A blockers 1 mM T16Ainh-A01 or 2 mM benzbromarone dissolved in 5% DMSO solution. All drugs were administered continuously via intradermal microdialysis. Whole-body heating increased core temperature progressively and this was paralleled by an increase in sweat rate and cutaneous vascular conductance at all skin sites. However, sweat rate (all P > 0.318) and cutaneous vascular conductance (all P ≥ 0.073) did not differ between the vehicle control site relative to the TMEM16A blocker-treated sites. Collectively, our findings indicate that TMEM16A blockers T16Ainh-A01 and benzbromarone do not modulate the regulation of sweating and cutaneous vasodilatation during whole-body heating in young adults in vivo.
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Affiliation(s)
- Naoto Fujii
- Faculty of Health and Sport Sciences, University of Tsukuba, Tsukuba, Japan
| | - Tatsuro Amano
- Laboratory for Exercise and Environmental Physiology, Faculty of Education, Niigata University, Niigata, Japan
| | - Glen P Kenny
- Human and Environmental Physiology Research Unit, University of Ottawa, Ottawa, Canada
| | - Toby Mündel
- School of Sport Exercise and Nutrition, Massey University, Palmerston North, New Zealand
| | - Tze-Huan Lei
- College of Physical Education, Hubei Normal University, Huangshi, China
| | - Yasushi Honda
- Faculty of Health and Sport Sciences, University of Tsukuba, Tsukuba, Japan
| | - Narihiko Kondo
- Laboratory for Applied Human Physiology, Graduate School of Human Development and Environment, Kobe University, Kobe, Japan
| | - Takeshi Nishiyasu
- Faculty of Health and Sport Sciences, University of Tsukuba, Tsukuba, Japan
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6
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Activation of Calcium-Activated Chloride Channels Suppresses Inherited Seizure Susceptibility in Genetically Epilepsy-Prone Rats. Biomedicines 2022; 10:biomedicines10020449. [PMID: 35203658 PMCID: PMC8962295 DOI: 10.3390/biomedicines10020449] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 01/31/2022] [Accepted: 02/09/2022] [Indexed: 01/27/2023] Open
Abstract
Inherited seizure susceptibility in genetically epilepsy-prone rats (GEPR-3s) is associated with increased voltage-gated calcium channel currents suggesting a massive calcium influx resulting in increased levels of intraneuronal calcium. Cytosolic calcium, in turn, activates many processes, including chloride channels, to restore normal membrane excitability and limit repetitive firing of the neurons. Here we used EACT and T16Ainh-A01, potent activator and inhibitor of calcium-activated channels transmembrane protein 16A (TMEM16A), respectively, to probe the role of these channels in the pathophysiology of acoustically evoked seizures in the GEPR-3s. We used adult male and female GEPR-3s. Acoustically evoked seizures consisted of wild running seizures (WRSs) that evolved into generalized tonic-clonic seizures (GTCSs) and eventually culminated into forelimb extension (partial tonic seizures). We found that acute EACT treatment at relatively higher tested doses significantly reduced the incidences of WRSs and GTCSs, and the seizure severity in male GEPR-3s. Furthermore, these antiseizure effects were associated with delayed seizure onset and reduced seizure duration. Interestingly, the inhibition of TMEM16A channels reversed EACT’s antiseizure effects on seizure latency and seizure duration. No notable antiseizure effects were observed in female GEPR-3s. Together, these findings suggest that activation of TMEM16A channels may represent a putative novel cellular mechanism for suppressing GTCSs.
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7
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Hernandez A, Alaniz-Palacios A, Contreras-Vite JA, Martínez-Torres A. Positive modulation of the TMEM16B mediated currents by TRPV4 antagonist. Biochem Biophys Rep 2021; 28:101180. [PMID: 34917777 PMCID: PMC8646129 DOI: 10.1016/j.bbrep.2021.101180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Revised: 11/23/2021] [Accepted: 11/29/2021] [Indexed: 11/30/2022] Open
Abstract
Calcium-activated chloride channels (CaCCs) play important roles in many physiological processes and their malfunction is implicated in diverse pathologies such as cancer, asthma, and hypertension. TMEM16A and TMEM16B proteins are the structural components of the CaCCs. Recent studies in cell cultures and animal models have demonstrated that pharmacological inhibition of CaCCs could be helpful in the treatment of some diseases, however, there are few specific modulators of these channels. CaCCs and Transient Receptor Potential Vanilloid-4 (TRPV4) channels are co-expressed in some tissues where they functionally interact. TRPV4 is activated by different stimuli and forms a calcium permeable channel that is activated by GSK1016790A and antagonized by GSK2193874. Here we report that GSK2193874 enhances the chloride currents mediated by TMEM16B expressed in HEK cells at nanomolar concentrations and that GSK1016790A enhances native CaCCs of Xenopus oocytes. Thus, these compounds may be used as a tool for the study of CaCCs, TRPV4 and their interactions.
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Affiliation(s)
- Adan Hernandez
- Departamento de Neurobiología Celular y Molecular, Laboratorio de Neurobiología Molecular y Celular, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Juriquilla, 76230 Santiago de Querétaro, Querétaro, Mexico
| | - Alfredo Alaniz-Palacios
- Departamento de Neurobiología Celular y Molecular, Laboratorio de Neurobiología Molecular y Celular, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Juriquilla, 76230 Santiago de Querétaro, Querétaro, Mexico
| | - Juan A Contreras-Vite
- Departamento de Neurobiología Celular y Molecular, Laboratorio de Neurobiología Molecular y Celular, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Juriquilla, 76230 Santiago de Querétaro, Querétaro, Mexico
| | - Ataúlfo Martínez-Torres
- Departamento de Neurobiología Celular y Molecular, Laboratorio de Neurobiología Molecular y Celular, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Juriquilla, 76230 Santiago de Querétaro, Querétaro, Mexico
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8
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Chen Q, Kong L, Xu Z, Cao N, Tang X, Gao R, Zhang J, Deng S, Tan C, Zhang M, Wang Y, Zhang L, Ma K, Li L, Si J. The Role of TMEM16A/ERK/NK-1 Signaling in Dorsal Root Ganglia Neurons in the Development of Neuropathic Pain Induced by Spared Nerve Injury (SNI). Mol Neurobiol 2021; 58:5772-5789. [PMID: 34406600 PMCID: PMC8599235 DOI: 10.1007/s12035-021-02520-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2021] [Accepted: 08/04/2021] [Indexed: 12/21/2022]
Abstract
Increasing evidence suggests that transmembrane protein 16A (TMEM16A) in nociceptive neurons is an important molecular component contributing to peripheral pain transduction. The present study aimed to evaluate the role and mechanism of TMEM16A in chronic nociceptive responses elicited by spared nerve injury (SNI). In this study, SNI was used to induce neuropathic pain. Drugs were administered intrathecally. The expression and cellular localization of TMEM16A, the ERK pathway, and NK-1 in the dorsal root ganglion (DRG) were detected by western blot and immunofluorescence. Behavioral tests were used to evaluate the role of TMEM16A and p-ERK in SNI-induced persistent pain and hypersensitivity. The role of TMEM16A in the hyperexcitability of primary nociceptor neurons was assessed by electrophysiological recording. The results show that TMEM16A, p-ERK, and NK-1 are predominantly expressed in small neurons associated with nociceptive sensation. TMEM16A is colocalized with p-ERK/NK-1 in DRG. TMEM16A, the MEK/ERK pathway, and NK-1 are activated in DRG after SNI. ERK inhibitor or TMEM16A antagonist prevents SNI-induced allodynia. ERK and NK-1 are downstream of TMEM16A activation. Electrophysiological recording showed that CaCC current increases and intrathecal application of T16Ainh-A01, a selective TMEM16A inhibitor, reverses the hyperexcitability of DRG neurons harvested from rats after SNI. We conclude that TMEM16A activation in DRG leads to a positive interaction of the ERK pathway with activation of NK-1 production and is involved in the development of neuropathic pain after SNI. Also, the blockade of TMEM16A or inhibition of the downstream ERK pathway or NK-1 upregulation may prevent the development of neuropathic pain.
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Affiliation(s)
- Qinyi Chen
- Department of Physiology, The Key Laboratory of Xinjiang Endemic and Ethnic Diseases, Shihezi University Medical College, Shihezi, China.,Department of Anesthesiology, Xiangyang Central Hospital, Affiliated Hospital of Hubei University of Arts and Science, Xiangyang, China.,NHC Key Laboratory of Prevention and Treatment of Central Asia High Incidence Diseases, First Affiliated Hospital, Shihezi University School of Medicine, Shihezi, China
| | - Liangjingyuan Kong
- Department of Physiology, The Key Laboratory of Xinjiang Endemic and Ethnic Diseases, Shihezi University Medical College, Shihezi, China.,NHC Key Laboratory of Prevention and Treatment of Central Asia High Incidence Diseases, First Affiliated Hospital, Shihezi University School of Medicine, Shihezi, China
| | - Zhenzhen Xu
- Department of Physiology, The Key Laboratory of Xinjiang Endemic and Ethnic Diseases, Shihezi University Medical College, Shihezi, China.,NHC Key Laboratory of Prevention and Treatment of Central Asia High Incidence Diseases, First Affiliated Hospital, Shihezi University School of Medicine, Shihezi, China.,Department of Anesthesiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Nan Cao
- Department of Physiology, The Key Laboratory of Xinjiang Endemic and Ethnic Diseases, Shihezi University Medical College, Shihezi, China.,NHC Key Laboratory of Prevention and Treatment of Central Asia High Incidence Diseases, First Affiliated Hospital, Shihezi University School of Medicine, Shihezi, China
| | - Xuechun Tang
- Department of Physiology, The Key Laboratory of Xinjiang Endemic and Ethnic Diseases, Shihezi University Medical College, Shihezi, China.,NHC Key Laboratory of Prevention and Treatment of Central Asia High Incidence Diseases, First Affiliated Hospital, Shihezi University School of Medicine, Shihezi, China
| | - Ruijuan Gao
- Department of Physiology, The Key Laboratory of Xinjiang Endemic and Ethnic Diseases, Shihezi University Medical College, Shihezi, China.,NHC Key Laboratory of Prevention and Treatment of Central Asia High Incidence Diseases, First Affiliated Hospital, Shihezi University School of Medicine, Shihezi, China
| | - Jingrong Zhang
- Department of Physiology, The Key Laboratory of Xinjiang Endemic and Ethnic Diseases, Shihezi University Medical College, Shihezi, China.,NHC Key Laboratory of Prevention and Treatment of Central Asia High Incidence Diseases, First Affiliated Hospital, Shihezi University School of Medicine, Shihezi, China
| | - Shiyu Deng
- Department of Physiology, The Key Laboratory of Xinjiang Endemic and Ethnic Diseases, Shihezi University Medical College, Shihezi, China.,NHC Key Laboratory of Prevention and Treatment of Central Asia High Incidence Diseases, First Affiliated Hospital, Shihezi University School of Medicine, Shihezi, China
| | - Chaoyang Tan
- Department of Physiology, The Key Laboratory of Xinjiang Endemic and Ethnic Diseases, Shihezi University Medical College, Shihezi, China.,NHC Key Laboratory of Prevention and Treatment of Central Asia High Incidence Diseases, First Affiliated Hospital, Shihezi University School of Medicine, Shihezi, China.,Department of Security, Karamay Army Division, Xinjiang Uygur Autonomous Region, Chinese People's Liberation Army, Karamay, China
| | - Meng Zhang
- Department of Anesthesiology, Sichuan Academy of Medical Sciences, Sichuan Provincial People's Hospital, Chengdu, China
| | - Yang Wang
- Department of Physiology, The Key Laboratory of Xinjiang Endemic and Ethnic Diseases, Shihezi University Medical College, Shihezi, China.,NHC Key Laboratory of Prevention and Treatment of Central Asia High Incidence Diseases, First Affiliated Hospital, Shihezi University School of Medicine, Shihezi, China
| | - Liang Zhang
- Department of Physiology, The Key Laboratory of Xinjiang Endemic and Ethnic Diseases, Shihezi University Medical College, Shihezi, China.,NHC Key Laboratory of Prevention and Treatment of Central Asia High Incidence Diseases, First Affiliated Hospital, Shihezi University School of Medicine, Shihezi, China
| | - Ketao Ma
- Department of Physiology, The Key Laboratory of Xinjiang Endemic and Ethnic Diseases, Shihezi University Medical College, Shihezi, China.,NHC Key Laboratory of Prevention and Treatment of Central Asia High Incidence Diseases, First Affiliated Hospital, Shihezi University School of Medicine, Shihezi, China
| | - Li Li
- Department of Physiology, The Key Laboratory of Xinjiang Endemic and Ethnic Diseases, Shihezi University Medical College, Shihezi, China. .,Department of Physiology, Medical College of Jiaxing University, Jiaxing, China.
| | - Junqiang Si
- Department of Physiology, The Key Laboratory of Xinjiang Endemic and Ethnic Diseases, Shihezi University Medical College, Shihezi, China. .,NHC Key Laboratory of Prevention and Treatment of Central Asia High Incidence Diseases, First Affiliated Hospital, Shihezi University School of Medicine, Shihezi, China. .,Department of Physiology, School of Basic Medicine and Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
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9
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Pinto MC, Silva IAL, Figueira MF, Amaral MD, Lopes-Pacheco M. Pharmacological Modulation of Ion Channels for the Treatment of Cystic Fibrosis. J Exp Pharmacol 2021; 13:693-723. [PMID: 34326672 PMCID: PMC8316759 DOI: 10.2147/jep.s255377] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Accepted: 06/30/2021] [Indexed: 12/12/2022] Open
Abstract
Cystic fibrosis (CF) is a life-shortening monogenic disease caused by mutations in the gene encoding the CF transmembrane conductance regulator (CFTR) protein, an anion channel that transports chloride and bicarbonate across epithelia. Despite clinical progress in delaying disease progression with symptomatic therapies, these individuals still develop various chronic complications in lungs and other organs, which significantly restricts their life expectancy and quality of life. The development of high-throughput assays to screen drug-like compound libraries have enabled the discovery of highly effective CFTR modulator therapies. These novel therapies target the primary defect underlying CF and are now approved for clinical use for individuals with specific CF genotypes. However, the clinically approved modulators only partially reverse CFTR dysfunction and there is still a considerable number of individuals with CF carrying rare CFTR mutations who remain without any effective CFTR modulator therapy. Accordingly, additional efforts have been pursued to identify novel and more potent CFTR modulators that may benefit a larger CF population. The use of ex vivo individual-derived specimens has also become a powerful tool to evaluate novel drugs and predict their effectiveness in a personalized medicine approach. In addition to CFTR modulators, pro-drugs aiming at modulating alternative ion channels/transporters are under development to compensate for the lack of CFTR function. These therapies may restore normal mucociliary clearance through a mutation-agnostic approach (ie, independent of CFTR mutation) and include inhibitors of the epithelial sodium channel (ENaC), modulators of the calcium-activated channel transmembrane 16A (TMEM16, or anoctamin 1) or of the solute carrier family 26A member 9 (SLC26A9), and anionophores. The present review focuses on recent progress and challenges for the development of ion channel/transporter-modulating drugs for the treatment of CF.
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Affiliation(s)
- Madalena C Pinto
- Biosystems & Integrative Sciences Institute (BioISI), Faculty of Sciences, University of Lisboa, Lisboa, Portugal
| | - Iris A L Silva
- Biosystems & Integrative Sciences Institute (BioISI), Faculty of Sciences, University of Lisboa, Lisboa, Portugal
| | - Miriam F Figueira
- Marsico Lung Institute/Cystic Fibrosis Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Margarida D Amaral
- Biosystems & Integrative Sciences Institute (BioISI), Faculty of Sciences, University of Lisboa, Lisboa, Portugal
| | - Miquéias Lopes-Pacheco
- Biosystems & Integrative Sciences Institute (BioISI), Faculty of Sciences, University of Lisboa, Lisboa, Portugal
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10
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Liu Y, Liu Z, Wang K. The Ca 2+-activated chloride channel ANO1/TMEM16A: An emerging therapeutic target for epithelium-originated diseases? Acta Pharm Sin B 2021; 11:1412-1433. [PMID: 34221860 PMCID: PMC8245819 DOI: 10.1016/j.apsb.2020.12.003] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 08/19/2020] [Accepted: 09/14/2020] [Indexed: 02/07/2023] Open
Abstract
Anoctamin 1 (ANO1) or TMEM16A gene encodes a member of Ca2+ activated Cl– channels (CaCCs) that are critical for physiological functions, such as epithelial secretion, smooth muscle contraction and sensory signal transduction. The attraction and interest in ANO1/TMEM16A arise from a decade long investigations that abnormal expression or dysfunction of ANO1 is involved in many pathological phenotypes and diseases, including asthma, neuropathic pain, hypertension and cancer. However, the lack of specific modulators of ANO1 has impeded the efforts to validate ANO1 as a therapeutic target. This review focuses on the recent progress made in understanding of the pathophysiological functions of CaCC ANO1 and the current modulators used as pharmacological tools, hopefully illustrating a broad spectrum of ANO1 channelopathy and a path forward for this target validation.
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Key Words
- ANO1
- ANO1, anoctamin-1
- ASM, airway smooth muscle
- Ang II, angiotensin II
- BBB, blood–brain barrier
- CAMK, Ca2+/calmodulin-dependent protein kinase
- CF, cystic fibrosis
- CFTR, cystic fibrosis transmembrane conductance regulator
- Ca2+-activated Cl– channels (CaCCs)
- CaCCinh-A01
- CaCCs, Ca2+ activated chloride channels
- Cancer
- Cystic fibrosis
- DRG, dorsal root ganglion
- Drug target
- EGFR, epidermal growth factor receptor
- ENaC, epithelial sodium channels
- ER, endoplasmic reticulum
- ESCC, esophageal squamous cell carcinoma
- FRT, fisher rat thyroid
- GI, gastrointestinal
- GIST, gastrointestinal stromal tumor
- GPCR, G-protein coupled receptor
- HNSCC, head and neck squamous cell carcinoma
- HTS, high-throughput screening
- ICC, interstitial cells of Cajal
- IPAH, idiopathic pulmonary arterial hypertension
- MAPK, mitogen-activated protein kinase
- NF-κB, nuclear factor κB
- PAH, pulmonary arterial hypertension
- PAR2, protease activated receptor 2
- PASMC, pulmonary artery smooth muscle cells
- PIP2, phosphatidylinositol 4,5-bisphosphate
- PKD, polycystic kidney disease
- T16Ainh-A01
- TGF-β, transforming growth factor-β
- TMEM16A
- VGCC, voltage gated calcium channel
- VRAC, volume regulated anion channel
- VSMC, vascular smooth muscle cells
- YFP, yellow fluorescent protein
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Affiliation(s)
- Yani Liu
- Department of Pharmacology, School of Pharmacy, Qingdao University Medical College, Qingdao 266073, China
- Institute of Innovative Drugs, Qingdao University, Qingdao 266021, China
| | - Zongtao Liu
- Department of Clinical Laboratory, Qingdao Third People's Hospital, Qingdao 266041, China
| | - KeWei Wang
- Department of Pharmacology, School of Pharmacy, Qingdao University Medical College, Qingdao 266073, China
- Institute of Innovative Drugs, Qingdao University, Qingdao 266021, China
- Corresponding authors.
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11
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Zhu X, Zhang W, Jin L, Zhang G, Yang H, Yu B. Inhibitory activities of curzerenone, curdione, furanodienone, curcumol and germacrone on Ca 2+-activated chloride channels. Fitoterapia 2020; 147:104736. [PMID: 33010370 DOI: 10.1016/j.fitote.2020.104736] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Revised: 08/30/2020] [Accepted: 09/25/2020] [Indexed: 02/06/2023]
Abstract
Calcium-activated chloride channels (CaCCs) as a kind of widely expressed ion channels play crucial roles in a variety of physiological regulation. TMEM16A has been identified as the molecular basis of CaCCs in numerous cell types and is considered a new drug target for many diseases. Regulating the function of TMEM16A through small molecule modulators has become a new strategy to improve respiratory and digestive dysfunction and even tumor therapy. Herein, we obtained 5 sesquiterpenoids, named curzerenone, curdione, furanodienone, curcumol and germacrone with TMEM16A inhibition and revealed their mechanism of action by fluorescent and electrophysiological assays. Cell-based YFP fluorescence data demonstrated that 5 compounds inhibited TMEM16A-mediated I- influx in a dose-dependent manner. To explore the mechanism of 5 compounds on CaCCs, FRT cells with high expression of TMEM16A, HBE, HT-29 and T84 cells and mouse colons were used in short-circuit current assay. Our results showed that 5 compounds inhibited the Ca2+-activated Cl- currents generated by the Eact, ATP and UTP stimulation, and this inhibitory effect was related not only to the direct inhibition of channel opening, but also the inhibition of intracellular Ca2+ concentration and K+ channel activity. In addition to CaCCs, these 5 compounds also had definite inhibitory activities against cystic fibrosis transmembrane regulator (CFTR) at the cellular level. In summary, these compounds have the potential to regulate the activites of TMEM16A/CaCCs and CFTR channels in vitro, providing a new class of lead compounds for the development of drugs for diseases related to chloride channel dysfunction.
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Affiliation(s)
- Xiaojuan Zhu
- School of Life Sciences, Liaoning Provincial Key Laboratory of Biotechnology and Drug Discovery, Liaoning Normal University, Dalian 116081, PR China
| | - Wanting Zhang
- School of Life Sciences, Liaoning Provincial Key Laboratory of Biotechnology and Drug Discovery, Liaoning Normal University, Dalian 116081, PR China
| | - Lingling Jin
- College of Basic Medical Sciences, Dalian Medical University, Dalian 116044, PR China
| | - Guangping Zhang
- Institute of Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing 100700, PR China
| | - Hong Yang
- School of Life Sciences, Liaoning Provincial Key Laboratory of Biotechnology and Drug Discovery, Liaoning Normal University, Dalian 116081, PR China.
| | - Bo Yu
- School of Life Sciences, Liaoning Provincial Key Laboratory of Biotechnology and Drug Discovery, Liaoning Normal University, Dalian 116081, PR China.
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12
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Danahay HL, Lilley S, Fox R, Charlton H, Sabater J, Button B, McCarthy C, Collingwood SP, Gosling M. TMEM16A Potentiation: A Novel Therapeutic Approach for the Treatment of Cystic Fibrosis. Am J Respir Crit Care Med 2020; 201:946-954. [PMID: 31898911 PMCID: PMC7159426 DOI: 10.1164/rccm.201908-1641oc] [Citation(s) in RCA: 56] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Rationale: Enhancing non–CFTR (cystic fibrosis transmembrane conductance regulator)-mediated anion secretion is an attractive therapeutic approach for the treatment of cystic fibrosis (CF) and other mucoobstructive diseases. Objectives: To determine the effects of TMEM16A potentiation on epithelial fluid secretion and mucociliary clearance. Methods: The effects of a novel low-molecular-weight TMEM16A potentiator (ETX001) were evaluated in human cell and animal models of airway epithelial function and mucus transport. Measurements and Main Results: Potentiating the activity of TMEM16A with ETX001 increased the Ca2+-activated Cl− channel activity and anion secretion in human bronchial epithelial (HBE) cells from patients with CF without impacting calcium signaling. ETX001 rapidly increased fluid secretion and airway surface liquid height in CF-HBE cells under both static conditions and conditions designed to mimic the shear stress associated with tidal breathing. In ovine models of mucus clearance (tracheal mucus velocity and mucociliary clearance), inhaled ETX001 was able to accelerate clearance both when CFTR function was reduced by administration of a pharmacological blocker and when CFTR was fully functional. Conclusions: Enhancing the activity of TMEM16A increases epithelial fluid secretion and enhances mucus clearance independent of CFTR function. TMEM16A potentiation is a novel approach for the treatment of patients with CF and non-CF mucoobstructive diseases.
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Affiliation(s)
| | - Sarah Lilley
- Sussex Drug Discovery Centre, University of Sussex, Brighton, United Kingdom
| | - Roy Fox
- Sussex Drug Discovery Centre, University of Sussex, Brighton, United Kingdom
| | - Holly Charlton
- Sussex Drug Discovery Centre, University of Sussex, Brighton, United Kingdom
| | - Juan Sabater
- Mount Sinai Medical Center of Florida, Miami, Florida; and
| | - Brian Button
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | | | | | - Martin Gosling
- Enterprise Therapeutics, Brighton, United Kingdom.,Sussex Drug Discovery Centre, University of Sussex, Brighton, United Kingdom
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13
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Wilke BU, Kummer KK, Leitner MG, Kress M. Chloride - The Underrated Ion in Nociceptors. Front Neurosci 2020; 14:287. [PMID: 32322187 PMCID: PMC7158864 DOI: 10.3389/fnins.2020.00287] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2019] [Accepted: 03/12/2020] [Indexed: 01/06/2023] Open
Abstract
In contrast to pain processing neurons in the spinal cord, where the importance of chloride conductances is already well established, chloride homeostasis in primary afferent neurons has received less attention. Sensory neurons maintain high intracellular chloride concentrations through balanced activity of Na+-K+-2Cl– cotransporter 1 (NKCC1) and K+-Cl– cotransporter 2 (KCC2). Whereas in other cell types activation of chloride conductances causes hyperpolarization, activation of the same conductances in primary afferent neurons may lead to inhibitory or excitatory depolarization depending on the actual chloride reversal potential and the total amount of chloride efflux during channel or transporter activation. Dorsal root ganglion (DRG) neurons express a multitude of chloride channel types belonging to different channel families, such as ligand-gated, ionotropic γ-aminobutyric acid (GABA) or glycine receptors, Ca2+-activated chloride channels of the anoctamin/TMEM16, bestrophin or tweety-homolog family, CLC chloride channels and transporters, cystic fibrosis transmembrane conductance regulator (CFTR) as well as volume-regulated anion channels (VRACs). Specific chloride conductances are involved in signal transduction and amplification at the peripheral nerve terminal, contribute to excitability and action potential generation of sensory neurons, or crucially shape synaptic transmission in the spinal dorsal horn. In addition, chloride channels can be modified by a plethora of inflammatory mediators affecting them directly, via protein-protein interaction, or through signaling cascades. Since chloride channels as well as mediators that modulate chloride fluxes are regulated in pain disorders and contribute to nociceptor excitation and sensitization it is timely and important to emphasize their critical role in nociceptive primary afferents in this review.
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Affiliation(s)
- Bettina U Wilke
- Institute of Physiology, Department of Physiology and Medical Physics, Medical University of Innsbruck, Innsbruck, Austria
| | - Kai K Kummer
- Institute of Physiology, Department of Physiology and Medical Physics, Medical University of Innsbruck, Innsbruck, Austria
| | - Michael G Leitner
- Institute of Physiology, Department of Physiology and Medical Physics, Medical University of Innsbruck, Innsbruck, Austria
| | - Michaela Kress
- Institute of Physiology, Department of Physiology and Medical Physics, Medical University of Innsbruck, Innsbruck, Austria
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14
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Centeio R, Cabrita I, Benedetto R, Talbi K, Ousingsawat J, Schreiber R, Sullivan JK, Kunzelmann K. Pharmacological Inhibition and Activation of the Ca 2+ Activated Cl - Channel TMEM16A. Int J Mol Sci 2020; 21:ijms21072557. [PMID: 32272686 PMCID: PMC7177308 DOI: 10.3390/ijms21072557] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 03/26/2020] [Accepted: 04/02/2020] [Indexed: 12/14/2022] Open
Abstract
TMEM16A is a Ca2+ activated Cl− channel with important functions in airways, intestine, and other epithelial organs. Activation of TMEM16A is proposed as a therapy in cystic fibrosis (CF) to reinstall airway Cl− secretion and to enhance airway surface liquid (ASL). This CFTR-agnostic approach is thought to improve mucociliary clearance and lung function in CF. This could indeed improve ASL, however, mucus release and airway contraction may also be induced by activators of TMEM16A, particularly in inflamed airways of patients with asthma, COPD, or CF. Currently, both activators and inhibitors of TMEM16A are developed and examined in different types of tissues. Here we compare activation and inhibition of endogenous and overexpressed TMEM16A and analyze potential off-target effects. The three well-known blockers benzbromarone, niclosamide, and Ani9 inhibited both TMEM16A and ATP-induced Ca2+ increase by variable degrees, depending on the cell type. Niclosamide, while blocking Ca2+ activated TMEM16A, also induced a subtle but significant Ca2+ store release and inhibited store-operated Ca2+ influx. Niclosamide, benzbromarone and Ani9 also affected TMEM16F whole cell currents, indicating limited specificity for these inhibitors. The compounds Eact, cinnamaldehyde, and melittin, as well as the phosphatidylinositol diC8-PIP2 are the reported activators of TMEM16A. However, the compounds were unable to activate endogenous TMEM16A in HT29 colonic epithelial cells. In contrast, TMEM16A overexpressed in HEK293 cells was potently stimulated by these activators. We speculate that overexpressed TMEM16A might have a better accessibility to intracellular Ca2+, which causes spontaneous activity even at basal intracellular Ca2+ concentrations. Small molecules may therefore potentiate pre-stimulated TMEM16A currents, but may otherwise fail to activate silent endogenous TMEM16A.
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Affiliation(s)
- Raquel Centeio
- Physiological Institute, University of Regensburg, D-93053 Regensburg, Germany; (R.C.); (I.C.); (R.B.); (K.T.); (J.O.); (R.S.)
| | - Inês Cabrita
- Physiological Institute, University of Regensburg, D-93053 Regensburg, Germany; (R.C.); (I.C.); (R.B.); (K.T.); (J.O.); (R.S.)
| | - Roberta Benedetto
- Physiological Institute, University of Regensburg, D-93053 Regensburg, Germany; (R.C.); (I.C.); (R.B.); (K.T.); (J.O.); (R.S.)
| | - Khaoula Talbi
- Physiological Institute, University of Regensburg, D-93053 Regensburg, Germany; (R.C.); (I.C.); (R.B.); (K.T.); (J.O.); (R.S.)
| | - Jiraporn Ousingsawat
- Physiological Institute, University of Regensburg, D-93053 Regensburg, Germany; (R.C.); (I.C.); (R.B.); (K.T.); (J.O.); (R.S.)
| | - Rainer Schreiber
- Physiological Institute, University of Regensburg, D-93053 Regensburg, Germany; (R.C.); (I.C.); (R.B.); (K.T.); (J.O.); (R.S.)
| | | | - Karl Kunzelmann
- Physiological Institute, University of Regensburg, D-93053 Regensburg, Germany; (R.C.); (I.C.); (R.B.); (K.T.); (J.O.); (R.S.)
- * Correspondence: ; Tel.: +49-(0)941-943-4302; Fax: +49-(0)941-943-4315
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15
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Danielsson J, Kuforiji AS, Yocum GT, Zhang Y, Xu D, Gallos G, Emala CW. Agonism of the TMEM16A calcium-activated chloride channel modulates airway smooth muscle tone. Am J Physiol Lung Cell Mol Physiol 2019; 318:L287-L295. [PMID: 31747299 DOI: 10.1152/ajplung.00552.2018] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
TMEM16A (anoctamin 1) is an important calcium-activated chloride channel in airway smooth muscle (ASM). We have previously shown that TMEM16A antagonists such as benzbromarone relax ASM and have proposed TMEM16A antagonists as novel therapies for asthma treatment. However, TMEM16A is also expressed on airway epithelium, and TMEM16A agonists are being investigated as novel therapies for cystic fibrosis. There are theoretical concerns that agonism of TMEM16A on ASM could lead to bronchospasm, making them detrimental as airway therapeutics. The TMEM16A agonist Eact induced a significant contraction of human ASM and guinea pig tracheal rings in an ex vivo organ bath model. Pretreatment with two different TMEM16A antagonists, benzbromarone or T16Ainh-A01, completely attenuated these Eact-induced contractions. Pretreatment with Eact alone augmented the maximum acetylcholine contraction. Pretreatment of A/J mice in vivo with nebulized Eact caused an augmentation of methacholine-induced increases in airway resistance measured by the forced oscillatory technique (flexiVent). Pretreatment with the TMEM16A antagonist benzbromarone significantly attenuated methacholine-induced increases in airway resistance. In in vitro cellular studies, TMEM16A was found to be expressed more abundantly in ASM compared with epithelial cells in culture (8-fold higher in ASM). Eact caused an increase in intracellular calcium in human ASM cells that was completely attenuated by pretreatment with benzbromarone. Eact acutely depolarized the plasma membrane potential of ASM cells, which was attenuated by benzbromarone or nifedipine. The TMEM16A agonist Eact modulates ASM contraction in both ex vivo and in vivo models, suggesting that agonism of TMEM16A may lead to clinically relevant bronchospasm.
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Affiliation(s)
| | - Aisha S Kuforiji
- Department of Anesthesiology, Columbia University, New York, New York
| | - Gene T Yocum
- Department of Anesthesiology, Columbia University, New York, New York
| | - Yi Zhang
- Department of Anesthesiology, Columbia University, New York, New York
| | - Dingbang Xu
- Department of Anesthesiology, Columbia University, New York, New York
| | - George Gallos
- Department of Anesthesiology, Columbia University, New York, New York
| | - Charles W Emala
- Department of Anesthesiology, Columbia University, New York, New York
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16
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Genovese M, Borrelli A, Venturini A, Guidone D, Caci E, Viscido G, Gambardella G, di Bernardo D, Scudieri P, Galietta LJV. TRPV4 and purinergic receptor signalling pathways are separately linked in airway epithelia to CFTR and TMEM16A chloride channels. J Physiol 2019; 597:5859-5878. [PMID: 31622498 DOI: 10.1113/jp278784] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Accepted: 10/09/2019] [Indexed: 01/09/2023] Open
Abstract
KEY POINTS Eact is a putative pharmacological activator of TMEM16A. Eact is strongly effective in recombinant Fischer rat thyroid (FRT) cells but not in airway epithelial cells with endogenous TMEM16A expression. Transcriptomic analysis, gene silencing and functional studies in FRT cells reveal that Eact is actually an activator of the Ca2+ -permeable TRPV4 channel. In airway epithelial cells TRPV4 and TMEM16A are expressed in separate cell types. Intracellular Ca2+ elevation by TRPV4 stimulation leads to CFTR channel activation. ABSTRACT TMEM16A is a Ca2+ -activated Cl- channel expressed in airway epithelial cells, particularly under conditions of mucus hypersecretion. To investigate the role of TMEM16A, we used Eact, a putative TMEM16A pharmacological activator. However, in contrast to purinergic stimulation, we found little effect of Eact on bronchial epithelial cells under conditions of high TMEM16A expression. We hypothesized that Eact is an indirect activator of TMEM16A. By a combination of approaches, including short-circuit current recordings, bulk and single cell RNA sequencing, intracellular Ca2+ imaging and RNA interference, we found that Eact is actually an activator of the Ca2+ -permeable TRPV4 channel and that the modest effect of this compound in bronchial epithelial cells is due to a separate expression of TMEM16A and TRPV4 in different cell types. Importantly, we found that TRPV4 stimulation induced activation of the CFTR Cl- channel. Our study reveals the existence of separate Ca2+ signalling pathways linked to different Cl- secretory processes.
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Affiliation(s)
- Michele Genovese
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Italy
| | - Anna Borrelli
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Italy
| | - Arianna Venturini
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Italy
| | - Daniela Guidone
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Italy
| | - Emanuela Caci
- UOC Genetica Medica, IRCCS Istituto Giannina Gaslini, Genova, Italy
| | - Gaetano Viscido
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Italy
| | | | - Diego di Bernardo
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Italy
| | - Paolo Scudieri
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Italy
| | - Luis J V Galietta
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Italy.,Department of Translational Medical Sciences (DISMET), Università di Napoli Federico II, Napoli, Italy
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17
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Ingram JR, Ahluwalia A. The pharmacology of itch. Br J Pharmacol 2019; 176:4419-4420. [PMID: 31612462 DOI: 10.1111/bph.14865] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
The article has been co-published with permission in British Journal of Dermatology and British Journal of Pharmacology. The articles are identical except for minor stylistic and spelling differences in keeping with each journal's style. Either citation can be used when citing this article.
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Affiliation(s)
- J R Ingram
- Division of Infection & Immunity, Cardiff University, Cardiff, UK
| | - A Ahluwalia
- William Harvey Research Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, UK
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18
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Ingram JR, Ahluwalia A. The pharmacology of itch. Br J Dermatol 2019; 184:e1-e2. [PMID: 31578709 DOI: 10.1111/bjd.18525] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- J R Ingram
- Division of Infection & Immunity, Cardiff University, Cardiff, U.K
| | - A Ahluwalia
- William Harvey Research Institute, Barts & The London School of Medicine & Dentistry, Queen Mary University of London, London, U.K
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19
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Miner K, Labitzke K, Liu B, Wang P, Henckels K, Gaida K, Elliott R, Chen JJ, Liu L, Leith A, Trueblood E, Hensley K, Xia XZ, Homann O, Bennett B, Fiorino M, Whoriskey J, Yu G, Escobar S, Wong M, Born TL, Budelsky A, Comeau M, Smith D, Phillips J, Johnston JA, McGivern JG, Weikl K, Powers D, Kunzelmann K, Mohn D, Hochheimer A, Sullivan JK. Drug Repurposing: The Anthelmintics Niclosamide and Nitazoxanide Are Potent TMEM16A Antagonists That Fully Bronchodilate Airways. Front Pharmacol 2019; 10:51. [PMID: 30837866 PMCID: PMC6382696 DOI: 10.3389/fphar.2019.00051] [Citation(s) in RCA: 87] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Accepted: 01/18/2019] [Indexed: 01/21/2023] Open
Abstract
There is an unmet need in severe asthma where approximately 40% of patients exhibit poor β-agonist responsiveness, suffer daily symptoms and show frequent exacerbations. Antagonists of the Ca2+-activated Cl- channel, TMEM16A, offers a new mechanism to bronchodilate airways and block the multiple contractiles operating in severe disease. To identify TMEM16A antagonists we screened a library of ∼580,000 compounds. The anthelmintics niclosamide, nitazoxanide, and related compounds were identified as potent TMEM16A antagonists that blocked airway smooth muscle depolarization and contraction. To evaluate whether TMEM16A antagonists resist use- and inflammatory-desensitization pathways limiting β-agonist action, we tested their efficacy under harsh conditions using maximally contracted airways or airways pretreated with a cytokine cocktail. Stunningly, TMEM16A antagonists fully bronchodilated airways, while the β-agonist isoproterenol showed only partial effects. Thus, antagonists of TMEM16A and repositioning of niclosamide and nitazoxanide represent an important additional treatment for patients with severe asthma and COPD that is poorly controlled with existing therapies. It is of note that drug repurposing has also attracted wide interest in niclosamide and nitazoxanide as a new treatment for cancer and infectious disease. For the first time we identify TMEM16A as a molecular target for these drugs and thus provide fresh insights into their mechanism for the treatment of these disorders in addition to respiratory disease.
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Affiliation(s)
- Kent Miner
- Department of Inflammation Research, Amgen Inc., Thousand Oaks, CA, United States
| | - Katja Labitzke
- Department of Therapeutic Discovery, Amgen Inc., Regensburg, Germany
| | - Benxian Liu
- Department of Inflammation Research, Amgen Inc., Thousand Oaks, CA, United States
| | - Paul Wang
- Department of Therapeutic Discovery, Amgen Inc., Thousand Oaks, CA, United States
| | - Kathryn Henckels
- Department of Inflammation Research, Amgen Inc., Thousand Oaks, CA, United States
| | - Kevin Gaida
- Department of Inflammation Research, Amgen Inc., Thousand Oaks, CA, United States
| | - Robin Elliott
- Department of Inflammation Research, Amgen Inc., Thousand Oaks, CA, United States
| | - Jian Jeffrey Chen
- Department of Medicinal Chemistry, Amgen Inc., Thousand Oaks, CA, United States
| | - Longbin Liu
- Department of Medicinal Chemistry, Amgen Inc., Thousand Oaks, CA, United States
| | - Anh Leith
- Department of Inflammation Research, Amgen Inc., Seattle, WA, United States
| | - Esther Trueblood
- Department of Comparative Biology and Safety Sciences, Amgen Inc., Seattle, WA, United States
- Department of Comparative Biology and Safety Sciences, Amgen Inc., Thousand Oaks, CA, United States
- Department of Comparative Biology and Safety Sciences, Amgen Inc., South San Francisco, CA, United States
| | - Kelly Hensley
- Department of Comparative Biology and Safety Sciences, Amgen Inc., Seattle, WA, United States
- Department of Comparative Biology and Safety Sciences, Amgen Inc., Thousand Oaks, CA, United States
- Department of Comparative Biology and Safety Sciences, Amgen Inc., South San Francisco, CA, United States
| | - Xing-Zhong Xia
- Department of Inflammation Research, Amgen Inc., Thousand Oaks, CA, United States
| | - Oliver Homann
- Genome Analysis Unit, Amgen Inc., South San Francisco, CA, United States
| | - Brian Bennett
- Department of Inflammation Research, Amgen Inc., Thousand Oaks, CA, United States
| | - Mike Fiorino
- Department of Inflammation Research, Amgen Inc., Thousand Oaks, CA, United States
| | - John Whoriskey
- Department of Inflammation Research, Amgen Inc., Thousand Oaks, CA, United States
| | - Gang Yu
- Department of Inflammation Research, Amgen Inc., Thousand Oaks, CA, United States
| | - Sabine Escobar
- Department of Inflammation Research, Amgen Inc., Seattle, WA, United States
| | - Min Wong
- Department of Inflammation Research, Amgen Inc., Thousand Oaks, CA, United States
| | - Teresa L. Born
- Department of Inflammation Research, Amgen Inc., Seattle, WA, United States
| | - Alison Budelsky
- Department of Inflammation Research, Amgen Inc., Seattle, WA, United States
| | - Mike Comeau
- Department of Inflammation Research, Amgen Inc., Seattle, WA, United States
| | - Dirk Smith
- Department of Inflammation Research, Amgen Inc., Seattle, WA, United States
| | - Jonathan Phillips
- Department of Inflammation Research, Amgen Inc., Thousand Oaks, CA, United States
| | - James A. Johnston
- Department of Inflammation Research, Amgen Inc., Thousand Oaks, CA, United States
| | - Joseph G. McGivern
- Department of Therapeutic Discovery, Amgen Inc., Thousand Oaks, CA, United States
| | - Kerstin Weikl
- Department of Therapeutic Discovery, Amgen Inc., Regensburg, Germany
| | - David Powers
- Department of Therapeutic Discovery, Amgen Inc., Thousand Oaks, CA, United States
| | - Karl Kunzelmann
- Institut für Physiologie, Universität Regensburg, Regensburg, Germany
| | - Deanna Mohn
- Department of Inflammation Research, Amgen Inc., Thousand Oaks, CA, United States
| | | | - John K. Sullivan
- Department of Inflammation Research, Amgen Inc., Thousand Oaks, CA, United States
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20
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Hibberd TJ, Feng J, Luo J, Yang P, Samineni VK, Gereau RW, Kelley N, Hu H, Spencer NJ. Optogenetic Induction of Colonic Motility in Mice. Gastroenterology 2018; 155:514-528.e6. [PMID: 29782847 PMCID: PMC6715392 DOI: 10.1053/j.gastro.2018.05.029] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Accepted: 04/12/2018] [Indexed: 02/03/2023]
Abstract
BACKGROUND & AIMS Strategies are needed to increase gastrointestinal transit without systemic pharmacologic agents. We investigated whether optogenetics, focal application of light to control enteric nervous system excitability, could be used to evoke propagating contractions and increase colonic transit in mice. METHODS We generated transgenic mice with Cre-mediated expression of light-sensitive channelrhodopsin-2 (ChR2) in calretinin neurons (CAL-ChR2 Cre+ mice); Cre- littermates served as controls. Colonic myenteric neurons were analyzed by immunohistochemistry, patch-clamp, and calcium imaging studies. Motility was assessed by mechanical, electrophysiological, and video recording in vitro and by fecal output in vivo. RESULTS In isolated colons, focal light stimulation of calretinin enteric neurons evoked classic polarized motor reflexes (50/58 stimulations), followed by premature anterograde propagating contractions (39/58 stimulations). Light stimulation could evoke motility from sites along the entire colon. These effects were prevented by neural blockade with tetrodotoxin (n = 2), and did not occur in control mice (n = 5). Light stimulation of proximal colon increased the proportion of natural fecal pellets expelled over 15 minutes in vitro (75% ± 17% vs 32% ± 8% for controls) (P < .05). In vivo, activation of wireless light-emitting diodes implanted onto the colon wall significantly increased hourly fecal pellet output in conscious, freely moving mice (4.2 ± 0.4 vs 1.3 ± 0.3 in controls) (P < .001). CONCLUSIONS In studies of mice, we found that focal activation of a subset of enteric neurons can increase motility of the entire colon in vitro, and fecal output in vivo. Optogenetic control of enteric neurons might therefore be used to modify gut motility.
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Affiliation(s)
- Timothy J Hibberd
- College of Medicine and Public Health & Centre for Neuroscience, Flinders University, Australia
| | - Jing Feng
- Department of Anesthesiology, The Center for the Study of Itch, Washington University School of Medicine, St. Louis, MO, USA
| | - Jialie Luo
- Department of Anesthesiology, The Center for the Study of Itch, Washington University School of Medicine, St. Louis, MO, USA
| | - Pu Yang
- Department of Anesthesiology, The Center for the Study of Itch, Washington University School of Medicine, St. Louis, MO, USA
| | - Vijay K Samineni
- Washington University Pain Center, Department of Anesthesiology, Washington University School of Medicine, St Louis, MO, USA
| | - Robert W Gereau
- Washington University Pain Center, Department of Anesthesiology, Washington University School of Medicine, St Louis, MO, USA
| | - Nigel Kelley
- SA Biomedical Engineering, SA Health, Government of South Australia, Australia
| | - Hongzhen Hu
- Department of Anesthesiology, The Center for the Study of Itch, Washington University School of Medicine, St Louis, Missouri.
| | - Nick J Spencer
- College of Medicine and Public Health and Centre for Neuroscience, Flinders University, Adelaide, Australia.
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21
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Esancy K, Condon L, Feng J, Kimball C, Curtright A, Dhaka A. A zebrafish and mouse model for selective pruritus via direct activation of TRPA1. eLife 2018; 7:32036. [PMID: 29561265 PMCID: PMC5912907 DOI: 10.7554/elife.32036] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Accepted: 03/19/2018] [Indexed: 11/13/2022] Open
Abstract
Little is known about the capacity of lower vertebrates to experience itch. A screen of itch-inducing compounds (pruritogens) in zebrafish larvae yielded a single pruritogen, the TLR7 agonist imiquimod, that elicited a somatosensory neuron response. Imiquimod induced itch-like behaviors in zebrafish distinct from those induced by the noxious TRPA1 agonist, allyl isothiocyanate. In the zebrafish, imiquimod-evoked somatosensory neuronal responses and behaviors were entirely dependent upon TRPA1, while in the mouse TRPA1 was required for the direct activation of somatosensory neurons and partially responsible for behaviors elicited by this pruritogen. Imiquimod was found to be a direct but weak TRPA1 agonist that activated a subset of TRPA1 expressing neurons. Imiquimod-responsive TRPA1 expressing neurons were significantly more sensitive to noxious stimuli than other TRPA1 expressing neurons. Together, these results suggest a model for selective itch via activation of a specialized subpopulation of somatosensory neurons with a heightened sensitivity to noxious stimuli. Itch is a common and uncomfortable sensation that creates a strong desire to scratch. This mechanism may have evolved so animals can remove harmful parasites or substances from themselves. Feelings like touch, pain, and itch arise when stimuli such as mechanical pressure, temperature, or chemicals activate groups of specialized neurons in the skin. This response takes place when certain proteins – or receptors – at the surface of the neurons are stimulated. For instance, TRP ion channels such as TRPA1 play an important role in both the itch and pain responses. In mammals, directly activating these channels elicits pain. Itch is felt when itch responsive receptors are activated on a distinct set of neurons, which in turn activate TRP receptors. Although these processes have been well-studied in mammals, little is known about the existence of itch sensation in other animals. To explore this, Esancy, Condon, Feng et al. exposed zebrafish to chemicals that induce itch in mammals, and found that imiquimod, a medicine used to treat certain skin conditions, can elicit itch in fish. When this chemical was injected into the lips of a fish, the animal rubbed them against the walls of its tank, akin to scratching an itch. Further experiments showed that imiquimod directly activated the pain-sensing ion channel TRPA1. In fact, this receptor was essential to the ‘scratching’ behavior: fish genetically engineered to lack TRPA1 did not react to the drug. Fluorescent proteins were then used to track when the neurons that carry TRPA1 were activated.This revealed that, in the skin of zebrafish, there are at least two functionally distinct populations neurons that express TRPA1. One population, whose activation is associated with the animal ‘scratching’, responds even when TRPA1 receives a low level of stimulation. The other population is less sensitive: it responds only to high-intensity stimuli and is associated with a pain response such as freezing and slower movements. Further experiments in the mouse suggest that this mechanism is present in mammals as well. This coding strategy explains how pain and itch can be experienced when the same receptors are being activated. Studying how animals like fish experience itch gives an insight into how detecting these sensations could have evolved. In turn, understanding this mechanism at the molecular and cellular levels may help find new ways to design better treatments for itch and pain disorders.
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Affiliation(s)
- Kali Esancy
- Department of Biological Structure, University of Washington, Seattle, United States.,Graduate Program in Neuroscience, University of Washington, Seattle, United States
| | - Logan Condon
- Department of Biological Structure, University of Washington, Seattle, United States
| | - Jing Feng
- Center for the Study of Itch, Washington University, St. Louis, United States
| | - Corinna Kimball
- Department of Biological Structure, University of Washington, Seattle, United States
| | - Andrew Curtright
- Department of Biological Structure, University of Washington, Seattle, United States
| | - Ajay Dhaka
- Department of Biological Structure, University of Washington, Seattle, United States.,Graduate Program in Neuroscience, University of Washington, Seattle, United States
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22
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Sensory TRP channels contribute differentially to skin inflammation and persistent itch. Nat Commun 2017; 8:980. [PMID: 29081531 PMCID: PMC5661746 DOI: 10.1038/s41467-017-01056-8] [Citation(s) in RCA: 95] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2017] [Accepted: 08/16/2017] [Indexed: 11/20/2022] Open
Abstract
Although both persistent itch and inflammation are commonly associated with allergic contact dermatitis (ACD), it is not known if they are mediated by shared or distinct signaling pathways. Here we show that both TRPA1 and TRPV1 channels are required for generating spontaneous scratching in a mouse model of ACD induced by squaric acid dibutylester (SADBE), a small molecule hapten, through directly promoting the excitability of pruriceptors. TRPV1 but not TRPA1 channels protect the skin inflammation, as genetic ablation of TRPV1 function or pharmacological ablation of TRPV1-positive sensory nerves promotes cutaneous inflammation in the SADBE-induced ACD. Our results demonstrate that persistent itch and inflammation are mediated by distinct cellular and molecular mechanisms in a mouse model of ACD. Identification of distinct roles of TRPA1 and TRPV1 in regulating itch and inflammation may provide new insights into the pathophysiology and treatment of chronic itch and inflammation in ACD patients. Allergic contact dermatitis is associated both with persistent itch and inflammation, but it is not known if these are mediated by shared signaling pathways. The authors show that persistent itch requires both TRPA1 and TRPV1, while TRPV1 has a protective role against skin inflammation in mice.
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23
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Kamaleddin MA. Molecular, biophysical, and pharmacological properties of calcium-activated chloride channels. J Cell Physiol 2017; 233:787-798. [PMID: 28121009 DOI: 10.1002/jcp.25823] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Accepted: 01/24/2017] [Indexed: 12/15/2022]
Abstract
Calcium-activated chloride channels (CaCCs) are a family of anionic transmembrane ion channels. They are mainly responsible for the movement of Cl- and other anions across the biological membranes, and they are widely expressed in different tissues. Since the Cl- flow into or out of the cell plays a crucial role in hyperpolarizing or depolarizing the cells, respectively, the impact of intracellular Ca2+ concentration on these channels is attracting a lot of attentions. After summarizing the molecular, biophysical, and pharmacological properties of CaCCs, the role of CaCCs in normal cellular functions will be discussed, and I will emphasize how dysregulation of CaCCs in pathological conditions can account for different diseases. A better understanding of CaCCs and a pivotal regulatory role of Ca2+ can shed more light on the therapeutic strategies for different neurological disorders that arise from chloride dysregulation, such as asthma, cystic fibrosis, and neuropathic pain.
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Affiliation(s)
- Mohammad Amin Kamaleddin
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Ontario, Canada.,Neurosciences and Mental Health, The Hospital for Sick Children, Toronto, Ontario, Canada
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24
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Feng J, Luo J, Mack MR, Yang P, Zhang F, Wang G, Gong X, Cai T, Mei Z, Kim BS, Yin S, Hu H. The antimicrobial peptide human beta-defensin 2 promotes itch through Toll-like receptor 4 signaling in mice. J Allergy Clin Immunol 2017; 140:885-888.e6. [PMID: 28442325 DOI: 10.1016/j.jaci.2017.03.035] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Revised: 02/10/2017] [Accepted: 03/14/2017] [Indexed: 01/06/2023]
Affiliation(s)
- Jing Feng
- Department of Anesthesiology, the Center for the Study of Itch, Washington University School of Medicine, St Louis, Mo
| | - Jialie Luo
- Department of Anesthesiology, the Center for the Study of Itch, Washington University School of Medicine, St Louis, Mo
| | - Madison R Mack
- Division of Dermatology, Washington University School of Medicine, St Louis, Mo
| | - Pu Yang
- Department of Anesthesiology, the Center for the Study of Itch, Washington University School of Medicine, St Louis, Mo
| | - Feng Zhang
- College of Pharmacy, South-Central University for Nationalities, Wuhan, Hubei, China
| | - Guan Wang
- College of Pharmacy, South-Central University for Nationalities, Wuhan, Hubei, China
| | - Xuan Gong
- College of Pharmacy, South-Central University for Nationalities, Wuhan, Hubei, China
| | - Tao Cai
- Department of Dermatology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Zhinan Mei
- College of Pharmacy, South-Central University for Nationalities, Wuhan, Hubei, China
| | - Brian S Kim
- Division of Dermatology, Washington University School of Medicine, St Louis, Mo
| | - Shijin Yin
- College of Pharmacy, South-Central University for Nationalities, Wuhan, Hubei, China.
| | - Hongzhen Hu
- Department of Anesthesiology, the Center for the Study of Itch, Washington University School of Medicine, St Louis, Mo.
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25
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Erratum. Br J Pharmacol 2016; 173:2808. [DOI: 10.1111/bph.13572] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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26
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Liu S, Feng J, Luo J, Yang P, Brett TJ, Hu H. Eact, a small molecule activator of TMEM16A, activates TRPV1 and elicits pain- and itch-related behaviours. Br J Pharmacol 2016; 173:1208-18. [PMID: 26756551 DOI: 10.1111/bph.13420] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2015] [Revised: 12/10/2015] [Accepted: 12/22/2015] [Indexed: 01/12/2023] Open
Abstract
BACKGROUND AND PURPOSE TMEM16A, also known as anoctamin 1 channel, is a member of the Ca(2+)-activated chloride channels family and serves as a heat sensor in the primary nociceptors. Eact is a recently discovered small molecule activator of the TMEM16A channel. Here, we asked if Eact produces pain- and itch-related responses in vivo and investigated the cellular and molecular basis of Eact-elicited responses in dorsal root ganglia (DRG) neurons. EXPERIMENTAL APPROACH We employed behavioural testing combined with pharmacological inhibition and genetic ablation approaches to identify transient receptor potential vanilloid 1 (TRPV1) as the prominent mediator for Eact-evoked itch- or pain-related responses. We investigated the effects of Eact on TRPV1 and TMEM16A channels expressed in HEK293T cells and in DRG neurons isolated from wild type and Trpv1(-/-) mice using Ca(2+) imaging and patch-clamp recordings. We also used site-directed mutagenesis to determine the molecular basis of Eact activation of TRPV1. KEY RESULTS Administration of Eact elicited both itch- and pain-related behaviours. Unexpectedly, the Eact-elicited behavioural responses were dependent on the function of TRPV1, as shown by pharmacological inhibition and genetic ablation studies. Eact activated membrane currents and increased intracellular free Ca(2+) in both TRPV1-expressing HEK293T cells and isolated DRG neurons in a TRPV1-dependent manner. Eact activation of the TRPV1 channel was severely attenuated by mutations disrupting the capsaicin-binding sites. CONCLUSIONS AND IMPLICATIONS Our results suggest that Eact activates primary sensory nociceptors and produces both pain and itch responses mainly through direct activation of TRPV1 channels.
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Affiliation(s)
- Shenbin Liu
- Department of Anesthesiology, The Center for the Study of Itch, Washington University School of Medicine, St. Louis, MO, 63110, USA.,Department of Integrative Medicine and Neurobiology, State Key Laboratory of Medical Neurobiology, Shanghai Medical College, Fudan University, Shanghai, 200032, China
| | - Jing Feng
- Department of Anesthesiology, The Center for the Study of Itch, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Jialie Luo
- Department of Anesthesiology, The Center for the Study of Itch, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Pu Yang
- Department of Anesthesiology, The Center for the Study of Itch, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Thomas J Brett
- Department of Internal Medicine, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Hongzhen Hu
- Department of Anesthesiology, The Center for the Study of Itch, Washington University School of Medicine, St. Louis, MO, 63110, USA
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