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Spari D, Schmid A, Sanchez-Taltavull D, Murugan S, Keller K, Ennaciri N, Salm L, Stroka D, Beldi G. Released bacterial ATP shapes local and systemic inflammation during abdominal sepsis. eLife 2024; 13:RP96678. [PMID: 39163101 PMCID: PMC11335348 DOI: 10.7554/elife.96678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/21/2024] Open
Abstract
Sepsis causes millions of deaths per year worldwide and is a current global health priority declared by the WHO. Sepsis-related deaths are a result of dysregulated inflammatory immune responses indicating the need to develop strategies to target inflammation. An important mediator of inflammation is extracellular adenosine triphosphate (ATP) that is released by inflamed host cells and tissues, and also by bacteria in a strain-specific and growth-dependent manner. Here, we investigated the mechanisms by which bacteria release ATP. Using genetic mutant strains of Escherichia coli (E. coli), we demonstrate that ATP release is dependent on ATP synthase within the inner bacterial membrane. In addition, impaired integrity of the outer bacterial membrane notably contributes to ATP release and is associated with bacterial death. In a mouse model of abdominal sepsis, local effects of bacterial ATP were analyzed using a transformed E. coli bearing an arabinose-inducible periplasmic apyrase hydrolyzing ATP to be released. Abrogating bacterial ATP release shows that bacterial ATP suppresses local immune responses, resulting in reduced neutrophil counts and impaired survival. In addition, bacterial ATP has systemic effects via its transport in outer membrane vesicles (OMV). ATP-loaded OMV are quickly distributed throughout the body and upregulated expression of genes activating degranulation in neutrophils, potentially contributing to the exacerbation of sepsis severity. This study reveals mechanisms of bacterial ATP release and its local and systemic roles in sepsis pathogenesis.
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Affiliation(s)
- Daniel Spari
- Department of Visceral Surgery and Medicine, Inselspital, Bern University Hospital, University Hospital of BernBernSwitzerland
- Department for BioMedical Research, Visceral Surgery and Medicine, University Hospital of BernBernSwitzerland
| | - Annina Schmid
- Department of Visceral Surgery and Medicine, Inselspital, Bern University Hospital, University Hospital of BernBernSwitzerland
- Department for BioMedical Research, Visceral Surgery and Medicine, University Hospital of BernBernSwitzerland
| | - Daniel Sanchez-Taltavull
- Department of Visceral Surgery and Medicine, Inselspital, Bern University Hospital, University Hospital of BernBernSwitzerland
- Department for BioMedical Research, Visceral Surgery and Medicine, University Hospital of BernBernSwitzerland
| | - Shaira Murugan
- Department of Visceral Surgery and Medicine, Inselspital, Bern University Hospital, University Hospital of BernBernSwitzerland
- Department for BioMedical Research, Visceral Surgery and Medicine, University Hospital of BernBernSwitzerland
| | - Keely Keller
- Department of Visceral Surgery and Medicine, Inselspital, Bern University Hospital, University Hospital of BernBernSwitzerland
- Department for BioMedical Research, Visceral Surgery and Medicine, University Hospital of BernBernSwitzerland
| | - Nadia Ennaciri
- Department of Visceral Surgery and Medicine, Inselspital, Bern University Hospital, University Hospital of BernBernSwitzerland
- Department for BioMedical Research, Visceral Surgery and Medicine, University Hospital of BernBernSwitzerland
| | - Lilian Salm
- Department of Visceral Surgery and Medicine, Inselspital, Bern University Hospital, University Hospital of BernBernSwitzerland
- Department for BioMedical Research, Visceral Surgery and Medicine, University Hospital of BernBernSwitzerland
| | - Deborah Stroka
- Department of Visceral Surgery and Medicine, Inselspital, Bern University Hospital, University Hospital of BernBernSwitzerland
- Department for BioMedical Research, Visceral Surgery and Medicine, University Hospital of BernBernSwitzerland
| | - Guido Beldi
- Department of Visceral Surgery and Medicine, Inselspital, Bern University Hospital, University Hospital of BernBernSwitzerland
- Department for BioMedical Research, Visceral Surgery and Medicine, University Hospital of BernBernSwitzerland
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Uzay B, Donmez-Demir B, Ozcan SY, Kocak EE, Yemisci M, Ozdemir YG, Dalkara T, Karatas H. The effect of P2X7 antagonism on subcortical spread of optogenetically-triggered cortical spreading depression and neuroinflammation. J Headache Pain 2024; 25:120. [PMID: 39044141 PMCID: PMC11267761 DOI: 10.1186/s10194-024-01807-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Accepted: 06/06/2024] [Indexed: 07/25/2024] Open
Abstract
Migraine is a neurological disorder characterized by episodes of severe headache. Cortical spreading depression (CSD), the electrophysiological equivalent of migraine aura, results in opening of pannexin 1 megachannels that release ATP and triggers parenchymal neuroinflammatory signaling cascade in the cortex. Migraine symptoms suggesting subcortical dysfunction bring subcortical spread of CSD under the light. Here, we investigated the role of purinergic P2X7 receptors on the subcortical spread of CSD and its consequent neuroinflammation using a potent and selective P2X7R antagonist, JNJ-47965567. P2X7R antagonism had no effect on the CSD threshold and characteristics but increased the latency to hypothalamic voltage deflection following CSD suggesting that ATP acts as a mediator in the subcortical spread. P2X7R antagonism also prevented cortical and subcortical neuronal activation following CSD, revealed by bilateral decrease in c-fos positive neuron count, and halted CSD-induced neuroinflammation revealed by decreased neuronal HMGB1 release and decreased nuclear translocation of NF-kappa B-p65 in astrocytes. In conclusion, our data suggest that P2X7R plays a role in CSD-induced neuroinflammation, subcortical spread of CSD and CSD-induced neuronal activation hence can be a potential target.
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Affiliation(s)
- Burak Uzay
- Institute of Neurological Sciences and Psychiatry, Hacettepe University, Sihhiye, Ankara, 06100, Türkiye
- Department of Pharmacology, Vanderbilt University, Nashville, TN, USA
| | - Buket Donmez-Demir
- Institute of Neurological Sciences and Psychiatry, Hacettepe University, Sihhiye, Ankara, 06100, Türkiye
| | - Sinem Yilmaz Ozcan
- Institute of Neurological Sciences and Psychiatry, Hacettepe University, Sihhiye, Ankara, 06100, Türkiye
| | - Emine Eren Kocak
- Institute of Neurological Sciences and Psychiatry, Hacettepe University, Sihhiye, Ankara, 06100, Türkiye
- Department of Psychiatry, Hacettepe University, Ankara, Türkiye
| | - Muge Yemisci
- Institute of Neurological Sciences and Psychiatry, Hacettepe University, Sihhiye, Ankara, 06100, Türkiye
- Department of Neurology, Hacettepe University, Ankara, Türkiye
| | - Yasemin Gursoy Ozdemir
- Institute of Neurological Sciences and Psychiatry, Hacettepe University, Sihhiye, Ankara, 06100, Türkiye
- School of Medicine, Koc University, Istanbul, Türkiye
| | - Turgay Dalkara
- Institute of Neurological Sciences and Psychiatry, Hacettepe University, Sihhiye, Ankara, 06100, Türkiye
- Department of Neurology, Hacettepe University, Ankara, Türkiye
| | - Hulya Karatas
- Institute of Neurological Sciences and Psychiatry, Hacettepe University, Sihhiye, Ankara, 06100, Türkiye.
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Heiliczer S, Yanko R, Sharav Y, Aframian DJ, Klutstein M, Wilensky A, Haviv Y. Oxidative stress-mediated proapoptosis signaling: A novel theory on the mechanism underlying the pathogenesis of burning mouth syndrome. J Am Dent Assoc 2024; 155:258-267. [PMID: 37966403 DOI: 10.1016/j.adaj.2023.08.014] [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] [Received: 05/14/2023] [Revised: 08/16/2023] [Accepted: 08/30/2023] [Indexed: 11/16/2023]
Abstract
BACKGROUND Burning mouth syndrome (BMS) is a chronic oral pain disorder characterized by a generalized burning sensation in the oral mucosa without apparent medical or dental causes. Despite various hypotheses proposed to explain BMS pathogenesis, a clear understanding of the cellular-level events and associated histologic and molecular findings is lacking. Advancing our understanding of BMS pathogenesis could facilitate the development of more targeted therapeutic interventions. TYPES OF STUDIES REVIEWED The authors conducted an extensive literature search and review of cellular mechanisms, focusing on evidence-based data that support a comprehensive hypothesis for BMS pathogenesis. The authors explored novel and detailed mechanisms that may account for the characteristic features of BMS. RESULTS The authors proposed that BMS symptoms arise from the uncontrolled activation of proapoptotic transmembrane calcium permeable channels expressed in intraoral mucosal nerve fibers. Elevated levels of reactive oxygen species or dysfunctional antiapoptosis pathways may lead to uncontrolled oxidative stress-mediated apoptosis signaling, resulting in upregulation of transmembrane transient receptor potential vanilloid type 1 and P2X 3 calcium channels in nociceptive fibers. Activation of these channels can cause nerve terminal depolarization, leading to generation of action potentials that are centrally interpreted as pain. CONCLUSIONS AND PRACTICAL IMPLICATIONS The authors present a novel hypothesis for BMS pathogenesis, highlighting the role of proapoptotic transmembrane calcium permeable channels and oxidative stress-mediated apoptosis signaling in the development of BMS symptoms. Understanding these underlying mechanisms could provide new insights into the development of targeted therapeutic interventions for BMS. Additional research is warranted to validate this hypothesis and explore potential avenues for effective management of BMS.
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Lalo U, Pankratov Y. ATP-mediated signalling in the central synapses. Neuropharmacology 2023; 229:109477. [PMID: 36841527 DOI: 10.1016/j.neuropharm.2023.109477] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2023] [Revised: 02/13/2023] [Accepted: 02/23/2023] [Indexed: 02/27/2023]
Abstract
ATP released from the synaptic terminals and astrocytes can activate neuronal P2 receptors at a variety of locations across the CNS. Although the postsynaptic ATP-mediated signalling does not bring a major contribution into the excitatory transmission, it is instrumental for slow and diffuse modulation of synaptic dynamics and neuronal firing in many CNS areas. Neuronal P2X and P2Y receptors can be activated by ATP released from the synaptic terminals, astrocytes and microglia and thereby can participate in the regulation of synaptic homeostasis and plasticity. There is growing evidence of importance of purinergic regulation of synaptic transmission in different physiological and pathological contexts. Here, we review the main mechanisms underlying the complexity and diversity of purinergic signalling and purinergic modulation in central neurons.
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Affiliation(s)
- Ulyana Lalo
- School of Life Sciences, University of Warwick, United Kingdom
| | - Yuriy Pankratov
- School of Life Sciences, University of Warwick, United Kingdom.
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Penolazzi L, Notarangelo MP, Lambertini E, Vultaggio-Poma V, Tarantini M, Di Virgilio F, Piva R. Unorthodox localization of P2X7 receptor in subcellular compartments of skeletal system cells. Front Cell Dev Biol 2023; 11:1180774. [PMID: 37215083 PMCID: PMC10192554 DOI: 10.3389/fcell.2023.1180774] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Accepted: 04/19/2023] [Indexed: 05/24/2023] Open
Abstract
Identifying the subcellular localization of a protein within a cell is often an essential step in understanding its function. The main objective of this report was to determine the presence of the P2X7 receptor (P2X7R) in healthy human cells of skeletal system, specifically osteoblasts (OBs), chondrocytes (Chs) and intervertebral disc (IVD) cells. This receptor is a member of the ATP-gated ion channel family, known to be a main sensor of extracellular ATP, the prototype of the danger signal released at sites of tissue damage, and a ubiquitous player in inflammation and cancer, including bone and cartilaginous tissues. Despite overwhelming data supporting a role in immune cell responses and tumor growth and progression, a complete picture of the pathophysiological functions of P2X7R, especially when expressed by non-immune cells, is lacking. Here we show that human wild-type P2X7R (P2X7A) was expressed in different samples of human osteoblasts, chondrocytes and intervertebral disc cells. By fluorescence microscopy (LM) and immunogold transmission electron microscopy we localized P2X7R not only in the canonical sites (plasma membrane and cytoplasm), but also in the nucleus of all the 3 cell types, especially IVD cells and OBs. P2X7R mitochondrial immunoreactivity was predominantly detected in OBs and IVD cells, but not in Chs. Evidence of subcellular localization of P2X7R may help to i. understand the participation of P2X7R in as yet unidentified signaling pathways in the joint and bone microenvironment, ii. identify pathologies associated with P2X7R mislocalization and iii. design specific targeted therapies.
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Affiliation(s)
- Letizia Penolazzi
- Department of Neuroscience and Rehabilitation, University of Ferrara, Ferrara, Italy
| | | | - Elisabetta Lambertini
- Department of Neuroscience and Rehabilitation, University of Ferrara, Ferrara, Italy
| | | | - Mario Tarantini
- Department of Medical Sciences, University of Ferrara, Ferrara, Italy
| | | | - Roberta Piva
- Department of Neuroscience and Rehabilitation, University of Ferrara, Ferrara, Italy
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Ducza L, Gajtkó A, Hegedűs K, Bakk E, Kis G, Gaál B, Takács R, Szücs P, Matesz K, Holló K. Neuronal P2X4 receptor may contribute to peripheral inflammatory pain in rat spinal dorsal horn. Front Mol Neurosci 2023; 16:1115685. [PMID: 36969557 PMCID: PMC10033954 DOI: 10.3389/fnmol.2023.1115685] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2022] [Accepted: 02/14/2023] [Indexed: 03/11/2023] Open
Abstract
ObjectiveIntense inflammation may result in pain, which manifests as spinal central sensitization. There is growing evidence that purinergic signaling plays a pivotal role in the orchestration of pain processing. Over the last decade the ionotropic P2X purino receptor 4 (P2X4) got into spotlight in neuropathic disorders, however its precise spinal expression was scantily characterized during inflammatory pain. Thus, we intended to analyze the receptor distribution within spinal dorsal horn and lumbar dorsal root ganglia (DRG) of rats suffering in inflammatory pain induced by complete Freund adjuvant (CFA).MethodsCFA-induced peripheral inflammation was validated by mechanical and thermal behavioral tests. In order to ensure about the putative alteration of spinal P2X4 receptor gene expression qPCR reactions were designed, followed by immunoperoxidase and Western blot experiments to assess changes at a protein level. Colocalization of P2X4 with neuronal and glial markers was investigated by double immunofluorescent labelings, which were subsequently analyzed with IMARIS software. Transmission electronmicroscopy was applied to study the ultrastructural localization of the receptor. Concurrently, in lumbar DRG cells similar methodology has been carried out to complete our observations.ResultsThe figures of mechanical and thermal behavioral tests proved the establishment of CFA-induced inflammatory pain. We observed significant enhancement of P2X4 transcript level within the spinal dorsal horn 3 days upon CFA administration. Elevation of P2X4 immunoreactivity within Rexed lamina I-II of the spinal gray matter was synchronous with mRNA expression, and confirmed by protein blotting. According to IMARIS analysis the robust protein increase was mainly detected on primary afferent axonterminals and GFAP-labelled astrocyte membrane compartments, but not on postsynaptic dendrites was also validated ultrastructurally within the spinal dorsal horn. Furthermore, lumbar DRG analysis demonstrated that peptidergic and non-peptidergic nociceptive subsets of ganglia cells were also abundantly positive for P2X4 receptor in CFA model.ConclusionHere we provide novel evidence about involvement of neuronal and glial P2X4 receptor in the establishment of inflammatory pain.
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Tian SX, Xu T, Shi RY, Cai YQ, Wu MH, Zhen SJ, Wang W, Zhou Y, Du JY, Fang JF, Shao XM, Liu BY, Jiang YL, He XF, Fang JQ, Liang Y. Analgesic effect of electroacupuncture on bone cancer pain in rat model: the role of peripheral P2X3 receptor. Purinergic Signal 2023; 19:13-27. [PMID: 35478452 PMCID: PMC9984641 DOI: 10.1007/s11302-022-09861-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Accepted: 03/28/2022] [Indexed: 11/25/2022] Open
Abstract
Upregulation of P2X3 receptor (P2X3R) has been strongly implicated in nociceptive signaling including bone cancer pain (BCP). The present study, using rat bone cancer model, aimed to explore the role of P2X3R in regulating rat pain behavior under the intervention of electroacupuncture (EA). The BCP model was successfully established by injection with MRMT-1 breast cancer cell into the medullary cavity of left tibia for 3 × 104 cells/3 μL PBS in rats as revealed by obvious bone destruction, decreased paw withdrawal thresholds (PWTs), and reduced paw withdrawal latencies (PWLs). Western blot analyses showed that P2X3R expression was significantly upregulated in ipsilateral lumbar 4-6 (L4-6) dorsal root ganglia (DRG), but the difference not seen in spinal cord dorsal horn (SCDH). With the in-depth study of P2X3R activation, we observed that intrathecal injection of P2X3R agonist α,β-meATP aggravated MRMT-1 induced BCP, while injection of P2X3R inhibitor A-317491 alleviated pain. Subsequently, we demonstrated that BCP induced mechanical allodynia and thermal hyperalgesia were attenuated after EA treatment. Under EA treatment, total P2X3R protein expression in ipsilateral DRGs was decreased, and it is worth mentioning that decreased expression of P2X3R membrane protein, which indicated that both the expression and membrane trafficking of P2X3R were inhibited by EA. The immunofluorescence assay showed that EA stimulation exerted functions by reducing the expression of P2X3R-positive cells in ipsilateral DRGs of BCP rats. Ca2+ imaging analysis revealed that the EA stimulation decreased the percentage of α,β-meATP responsive neurons in DRGs and inhibited calcium influx. Notably, the inhibitory effect of EA on mechanical allodynia and nociceptive flinches was abolished by intrathecal injection of α,β-meATP. These findings demonstrated EA stimulation ameliorated mechanical allodynia and thermal hyperalgesia in rat model of MRMT-1-induced BCP. EA exerts analgesic effect on BCP by reducing the overexpression and functional activity of P2X3R in ipsilateral DRGs of BCP rats. Our work first demonstrates the critical and overall role of P2X3R in EA's analgesia against peripheral sensitization of MRMT-1-induced BCP and further supports EA as a potential therapeutic option for cancer pain in clinic.
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Affiliation(s)
- Shu-Xin Tian
- Department of Neurobiology and Acupuncture Research, The Third School of Clinical Medicine, Key Laboratory of Acupuncture and Neurology of Zhejiang Province, Zhejiang Chinese Medical University, 548 Binwen Road, Binjiang District, Hangzhou, 310053, Zhejiang Province, China
| | - Ting Xu
- Department of Neurobiology and Acupuncture Research, The Third School of Clinical Medicine, Key Laboratory of Acupuncture and Neurology of Zhejiang Province, Zhejiang Chinese Medical University, 548 Binwen Road, Binjiang District, Hangzhou, 310053, Zhejiang Province, China
| | - Ren-Yi Shi
- Department of Acupuncture and Moxibustion, Sanya Traditional Chinese Medicine Hospital, Sanya, 572000, China
| | - Yang-Qian Cai
- Department of Neurobiology and Acupuncture Research, The Third School of Clinical Medicine, Key Laboratory of Acupuncture and Neurology of Zhejiang Province, Zhejiang Chinese Medical University, 548 Binwen Road, Binjiang District, Hangzhou, 310053, Zhejiang Province, China
| | - Ming-Hui Wu
- Department of Neurobiology and Acupuncture Research, The Third School of Clinical Medicine, Key Laboratory of Acupuncture and Neurology of Zhejiang Province, Zhejiang Chinese Medical University, 548 Binwen Road, Binjiang District, Hangzhou, 310053, Zhejiang Province, China
| | - Si-Jia Zhen
- Department of Neurobiology and Acupuncture Research, The Third School of Clinical Medicine, Key Laboratory of Acupuncture and Neurology of Zhejiang Province, Zhejiang Chinese Medical University, 548 Binwen Road, Binjiang District, Hangzhou, 310053, Zhejiang Province, China
| | - Wen Wang
- Department of Neurobiology and Acupuncture Research, The Third School of Clinical Medicine, Key Laboratory of Acupuncture and Neurology of Zhejiang Province, Zhejiang Chinese Medical University, 548 Binwen Road, Binjiang District, Hangzhou, 310053, Zhejiang Province, China
| | - You Zhou
- Department of Neurobiology and Acupuncture Research, The Third School of Clinical Medicine, Key Laboratory of Acupuncture and Neurology of Zhejiang Province, Zhejiang Chinese Medical University, 548 Binwen Road, Binjiang District, Hangzhou, 310053, Zhejiang Province, China
| | - Jun-Ying Du
- Department of Neurobiology and Acupuncture Research, The Third School of Clinical Medicine, Key Laboratory of Acupuncture and Neurology of Zhejiang Province, Zhejiang Chinese Medical University, 548 Binwen Road, Binjiang District, Hangzhou, 310053, Zhejiang Province, China
| | - Jun-Fan Fang
- Department of Neurobiology and Acupuncture Research, The Third School of Clinical Medicine, Key Laboratory of Acupuncture and Neurology of Zhejiang Province, Zhejiang Chinese Medical University, 548 Binwen Road, Binjiang District, Hangzhou, 310053, Zhejiang Province, China
| | - Xiao-Mei Shao
- Department of Neurobiology and Acupuncture Research, The Third School of Clinical Medicine, Key Laboratory of Acupuncture and Neurology of Zhejiang Province, Zhejiang Chinese Medical University, 548 Binwen Road, Binjiang District, Hangzhou, 310053, Zhejiang Province, China
| | - Bo-Yi Liu
- Department of Neurobiology and Acupuncture Research, The Third School of Clinical Medicine, Key Laboratory of Acupuncture and Neurology of Zhejiang Province, Zhejiang Chinese Medical University, 548 Binwen Road, Binjiang District, Hangzhou, 310053, Zhejiang Province, China
| | - Yong-Liang Jiang
- Department of Neurobiology and Acupuncture Research, The Third School of Clinical Medicine, Key Laboratory of Acupuncture and Neurology of Zhejiang Province, Zhejiang Chinese Medical University, 548 Binwen Road, Binjiang District, Hangzhou, 310053, Zhejiang Province, China
| | - Xiao-Fen He
- Department of Neurobiology and Acupuncture Research, The Third School of Clinical Medicine, Key Laboratory of Acupuncture and Neurology of Zhejiang Province, Zhejiang Chinese Medical University, 548 Binwen Road, Binjiang District, Hangzhou, 310053, Zhejiang Province, China
| | - Jian-Qiao Fang
- Department of Neurobiology and Acupuncture Research, The Third School of Clinical Medicine, Key Laboratory of Acupuncture and Neurology of Zhejiang Province, Zhejiang Chinese Medical University, 548 Binwen Road, Binjiang District, Hangzhou, 310053, Zhejiang Province, China.,Department of Acupuncture and Moxibustion, The Third Affiliated Hospital of Zhejiang, Chinese Medical University, Hangzhou, 310005, China
| | - Yi Liang
- Department of Neurobiology and Acupuncture Research, The Third School of Clinical Medicine, Key Laboratory of Acupuncture and Neurology of Zhejiang Province, Zhejiang Chinese Medical University, 548 Binwen Road, Binjiang District, Hangzhou, 310053, Zhejiang Province, China. .,Department of Acupuncture and Moxibustion, The Third Affiliated Hospital of Zhejiang, Chinese Medical University, Hangzhou, 310005, China.
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Chun BJ, Aryal SP, Varughese P, Sun B, Bruno JA, Richards CI, Bachstetter AD, Kekenes-Huskey PM. Purinoreceptors and ectonucleotidases control ATP-induced calcium waveforms and calcium-dependent responses in microglia: Roles of P2 receptors and CD39 in ATP-stimulated microglia. Front Physiol 2023; 13:1037417. [PMID: 36699679 PMCID: PMC9868579 DOI: 10.3389/fphys.2022.1037417] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Accepted: 12/12/2022] [Indexed: 01/11/2023] Open
Abstract
Adenosine triphosphate (ATP) and its metabolites drive microglia migration and cytokine production by activating P2X- and P2Y- class purinergic receptors. Purinergic receptor activation gives rise to diverse intracellular calcium (Ca2+ signals, or waveforms, that differ in amplitude, duration, and frequency. Whether and how these characteristics of diverse waveforms influence microglia function is not well-established. We developed a computational model trained with data from published primary murine microglia studies. We simulate how purinoreceptors influence Ca2+ signaling and migration, as well as, how purinoreceptor expression modifies these processes. Our simulation confirmed that P2 receptors encode the amplitude and duration of the ATP-induced Ca2+ waveforms. Our simulations also implicate CD39, an ectonucleotidase that rapidly degrades ATP, as a regulator of purinergic receptor-induced Ca2+ responses. Namely, it was necessary to account for CD39 metabolism of ATP to align the model's predicted purinoreceptor responses with published experimental data. In addition, our modeling results indicate that small Ca2+ transients accompany migration, while large and sustained transients are needed for cytokine responses. Lastly, as a proof-of-principal, we predict Ca2+ transients and cell membrane displacements in a BV2 microglia cell line using published P2 receptor mRNA data to illustrate how our computer model may be extrapolated to other microglia subtypes. These findings provide important insights into how differences in purinergic receptor expression influence microglial responses to ATP.
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Affiliation(s)
- Byeong J. Chun
- Department of Cell and Molecular Physiology, Loyola University Chicago, Chicago, IL, United States,*Correspondence: Byeong J. Chun, ; Peter M. Kekenes-Huskey,
| | - Surya P. Aryal
- Department of Chemistry, University of Kentucky, Lexington, KY, United States
| | - Peter Varughese
- Department of Cell and Molecular Physiology, Loyola University Chicago, Chicago, IL, United States
| | - Bin Sun
- Department of Cell and Molecular Physiology, Loyola University Chicago, Chicago, IL, United States
| | - Joshua A. Bruno
- Department of Physics, Loyola University Chicago, Chicago, IL, United States
| | - Chris I. Richards
- Department of Chemistry, University of Kentucky, Lexington, KY, United States
| | | | - Peter M. Kekenes-Huskey
- Department of Cell and Molecular Physiology, Loyola University Chicago, Chicago, IL, United States,*Correspondence: Byeong J. Chun, ; Peter M. Kekenes-Huskey,
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Passarella D, Ronci M, Di Liberto V, Zuccarini M, Mudò G, Porcile C, Frinchi M, Di Iorio P, Ulrich H, Russo C. Bidirectional Control between Cholesterol Shuttle and Purine Signal at the Central Nervous System. Int J Mol Sci 2022; 23:ijms23158683. [PMID: 35955821 PMCID: PMC9369131 DOI: 10.3390/ijms23158683] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Revised: 07/29/2022] [Accepted: 08/01/2022] [Indexed: 12/07/2022] Open
Abstract
Recent studies have highlighted the mechanisms controlling the formation of cerebral cholesterol, which is synthesized in situ primarily by astrocytes, where it is loaded onto apolipoproteins and delivered to neurons and oligodendrocytes through interactions with specific lipoprotein receptors. The “cholesterol shuttle” is influenced by numerous proteins or carbohydrates, which mainly modulate the lipoprotein receptor activity, function and signaling. These molecules, provided with enzymatic/proteolytic activity leading to the formation of peptide fragments of different sizes and specific sequences, could be also responsible for machinery malfunctions, which are associated with neurological, neurodegenerative and neurodevelopmental disorders. In this context, we have pointed out that purines, ancestral molecules acting as signal molecules and neuromodulators at the central nervous system, can influence the homeostatic machinery of the cerebral cholesterol turnover and vice versa. Evidence gathered so far indicates that purine receptors, mainly the subtypes P2Y2, P2X7 and A2A, are involved in the pathogenesis of neurodegenerative diseases, such as Alzheimer’s and Niemann–Pick C diseases, by controlling the brain cholesterol homeostasis; in addition, alterations in cholesterol turnover can hinder the purine receptor function. Although the precise mechanisms of these interactions are currently poorly understood, the results here collected on cholesterol–purine reciprocal control could hopefully promote further research.
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Affiliation(s)
- Daniela Passarella
- Department of Medicine and Health Sciences “V. Tiberio”, University of Molise, 86100 Campobasso, Italy
| | - Maurizio Ronci
- Department of Pharmacy, University of Chieti-Pescara, 66100 Chieti, Italy
| | - Valentina Di Liberto
- Department of Experimental Biomedicine and Clinical Neurosciences, University of Palermo, 90133 Palermo, Italy
| | - Mariachiara Zuccarini
- Department of Medical Oral and Biotechnological Sciences, University of Chieti-Pescara, 66100 Chieti, Italy
| | - Giuseppa Mudò
- Department of Experimental Biomedicine and Clinical Neurosciences, University of Palermo, 90133 Palermo, Italy
| | - Carola Porcile
- Department of Medicine and Health Sciences “V. Tiberio”, University of Molise, 86100 Campobasso, Italy
| | - Monica Frinchi
- Department of Experimental Biomedicine and Clinical Neurosciences, University of Palermo, 90133 Palermo, Italy
| | - Patrizia Di Iorio
- Department of Medical Oral and Biotechnological Sciences, University of Chieti-Pescara, 66100 Chieti, Italy
| | - Henning Ulrich
- Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo 05508-060, Brazil
| | - Claudio Russo
- Department of Medicine and Health Sciences “V. Tiberio”, University of Molise, 86100 Campobasso, Italy
- Correspondence: ; Tel.: +39-087-440-4897
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Bertin E, Martinez A, Fayoux A, Carvalho K, Carracedo S, Fernagut PO, Koch-Nolte F, Blum D, Bertrand SS, Boué-Grabot E. Increased surface P2X4 receptors by mutant SOD1 proteins contribute to ALS pathogenesis in SOD1-G93A mice. Cell Mol Life Sci 2022; 79:431. [PMID: 35852606 PMCID: PMC9296432 DOI: 10.1007/s00018-022-04461-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Revised: 05/27/2022] [Accepted: 06/30/2022] [Indexed: 12/26/2022]
Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal motoneuron (MN) disease characterized by protein misfolding and aggregation leading to cellular degeneration. So far neither biomarker, nor effective treatment has been found. ATP signaling and P2X4 receptors (P2X4) are upregulated in various neurodegenerative diseases. Here we show that several ALS-related misfolded proteins including mutants of SOD1 or TDP-43 lead to a significant increase in surface P2X4 receptor density and function in vitro. In addition, we demonstrate in the spinal the cord of SOD1-G93A (SOD1) mice that misfolded SOD1-G93A proteins directly interact with endocytic adaptor protein-2 (AP2); thus, acting as negative competitors for the interaction between AP2 and P2X4, impairing constitutive P2X4 endocytosis. The higher P2X4 surface density was particularly observed in peripheral macrophages of SOD1 mice before the onset and during the progression of ALS symptoms positioning P2X4 as a potential early biomarker for ALS. P2X4 expression was also upregulated in spinal microglia of SOD1 mice during ALS and affect microglial inflammatory responses. Importantly, we report using double transgenic SOD1 mice expressing internalization-defective P2X4mCherryIN knock-in gene or invalidated for the P2X4 gene that P2X4 is instrumental for motor symptoms, ALS progression and survival. This study highlights the role of P2X4 in the pathophysiology of ALS and thus its potential for the development of biomarkers and treatments. We also decipher the molecular mechanism by which misfolded proteins related to ALS impact P2X4 trafficking at early pathological stage in cells expressing-P2X4.
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Affiliation(s)
- Eléonore Bertin
- Univ. Bordeaux, CNRS, IMN, UMR 5293, 33000, Bordeaux, France
| | - Audrey Martinez
- Univ. Bordeaux, CNRS, IMN, UMR 5293, 33000, Bordeaux, France
| | - Anne Fayoux
- Univ. Bordeaux, CNRS, EPHE, INCIA, UMR 5287, 33000, Bordeaux, France
| | - Kevin Carvalho
- Univ. Lille, Inserm, CHU Lille, U1172, LilNCog, Lille, France.,"Alzheimer & Tauopathies", LabEx DISTALZ, 59000, Lille, France
| | - Sara Carracedo
- Univ. Bordeaux, CNRS, IMN, UMR 5293, 33000, Bordeaux, France
| | | | - Friedrich Koch-Nolte
- Institute of Immunology, University Medical Center Hamburg-Eppendorf, 20246, Hamburg, Germany
| | - David Blum
- Univ. Lille, Inserm, CHU Lille, U1172, LilNCog, Lille, France.,"Alzheimer & Tauopathies", LabEx DISTALZ, 59000, Lille, France
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11
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Randzavola LO, Mortimer PM, Garside E, Dufficy ER, Schejtman A, Roumelioti G, Yu L, Pardo M, Spirohn K, Tolley C, Brandt C, Harcourt K, Nichols E, Nahorski M, Woods G, Williamson JC, Suresh S, Sowerby JM, Matsumoto M, Santos CXC, Kiar CS, Mukhopadhyay S, Rae WM, Dougan GJ, Grainger J, Lehner PJ, Calderwood MA, Choudhary J, Clare S, Speak A, Santilli G, Bateman A, Smith KGC, Magnani F, Thomas DC. EROS is a selective chaperone regulating the phagocyte NADPH oxidase and purinergic signalling. eLife 2022; 11:76387. [PMID: 36421765 PMCID: PMC9767466 DOI: 10.7554/elife.76387] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Accepted: 10/31/2022] [Indexed: 11/25/2022] Open
Abstract
EROS (essential for reactive oxygen species) protein is indispensable for expression of gp91phox, the catalytic core of the phagocyte NADPH oxidase. EROS deficiency in humans is a novel cause of the severe immunodeficiency, chronic granulomatous disease, but its mechanism of action was unknown until now. We elucidate the role of EROS, showing it acts at the earliest stages of gp91phox maturation. It binds the immature 58 kDa gp91phox directly, preventing gp91phox degradation and allowing glycosylation via the oligosaccharyltransferase machinery and the incorporation of the heme prosthetic groups essential for catalysis. EROS also regulates the purine receptors P2X7 and P2X1 through direct interactions, and P2X7 is almost absent in EROS-deficient mouse and human primary cells. Accordingly, lack of murine EROS results in markedly abnormal P2X7 signalling, inflammasome activation, and T cell responses. The loss of both ROS and P2X7 signalling leads to resistance to influenza infection in mice. Our work identifies EROS as a highly selective chaperone for key proteins in innate and adaptive immunity and a rheostat for immunity to infection. It has profound implications for our understanding of immune physiology, ROS dysregulation, and possibly gene therapy.
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Affiliation(s)
- Lyra O Randzavola
- Department of Immunology and Inflammation, Centre for Inflammatory Disease, Imperial College LondonLondonUnited Kingdom
| | - Paige M Mortimer
- Department of Immunology and Inflammation, Centre for Inflammatory Disease, Imperial College LondonLondonUnited Kingdom
| | - Emma Garside
- Department of Immunology and Inflammation, Centre for Inflammatory Disease, Imperial College LondonLondonUnited Kingdom
| | - Elizabeth R Dufficy
- The Department of Medicine, University of Cambridge School of Clinical MedicineCambridgeUnited Kingdom
| | - Andrea Schejtman
- Molecular Immunology Unit, UCL Great Ormond Street Institute of Child HealthLondonUnited Kingdom
| | - Georgia Roumelioti
- Functional Proteomics, Division of Cancer Biology, Institute of Cancer ResearchLondonUnited Kingdom
| | - Lu Yu
- Functional Proteomics, Division of Cancer Biology, Institute of Cancer ResearchLondonUnited Kingdom
| | - Mercedes Pardo
- Functional Proteomics, Division of Cancer Biology, Institute of Cancer ResearchLondonUnited Kingdom
| | - Kerstin Spirohn
- Center for Cancer Systems Biology (CCSB), Dana-Farber Cancer InstituteBostonUnited States,Department of Genetics, Blavatnik Institute, Harvard Medical SchoolBostonUnited States,Department of Cancer Biology, Dana-Farber Cancer InstituteBostonUnited States
| | | | | | | | - Esme Nichols
- Department of Immunology and Inflammation, Centre for Inflammatory Disease, Imperial College LondonLondonUnited Kingdom
| | - Mike Nahorski
- Cambridge Institute of Medical Research, University of CambridgeCambridgeUnited Kingdom
| | - Geoff Woods
- Cambridge Institute of Medical Research, University of CambridgeCambridgeUnited Kingdom
| | - James C Williamson
- The Department of Medicine, University of Cambridge School of Clinical MedicineCambridgeUnited Kingdom,Cambridge Institute of Therapeutic Immunology & Infectious Disease, Jeffrey Cheah Biomedical Centre Cambridge Biomedical CampusCambridgeUnited Kingdom
| | - Shreehari Suresh
- The Department of Medicine, University of Cambridge School of Clinical MedicineCambridgeUnited Kingdom
| | - John M Sowerby
- The Department of Medicine, University of Cambridge School of Clinical MedicineCambridgeUnited Kingdom,Cambridge Institute of Therapeutic Immunology & Infectious Disease, Jeffrey Cheah Biomedical Centre Cambridge Biomedical CampusCambridgeUnited Kingdom
| | - Misaki Matsumoto
- Department of Pharmacology, Kyoto Prefectural University of MedicineKyotoJapan
| | - Celio XC Santos
- School of Cardiovascular Medicine and Sciences, James Black Centre, King's College LondonLondonUnited Kingdom
| | - Cher Shen Kiar
- Peter Gorer Department of Immunobiology, School of Immunology & Microbial Sciences, King's College LondonLondonUnited Kingdom
| | - Subhankar Mukhopadhyay
- Peter Gorer Department of Immunobiology, School of Immunology & Microbial Sciences, King's College LondonLondonUnited Kingdom
| | - William M Rae
- The Department of Medicine, University of Cambridge School of Clinical MedicineCambridgeUnited Kingdom,Cambridge Institute of Therapeutic Immunology & Infectious Disease, Jeffrey Cheah Biomedical Centre Cambridge Biomedical CampusCambridgeUnited Kingdom
| | - Gordon J Dougan
- The Department of Medicine, University of Cambridge School of Clinical MedicineCambridgeUnited Kingdom
| | - John Grainger
- Functional Proteomics, Division of Cancer Biology, Institute of Cancer ResearchLondonUnited Kingdom,Lydia Becker Institute of Immunology and Inflammation, Faculty of Biology, Medicine and Health, University of ManchesterManchesterUnited Kingdom
| | - Paul J Lehner
- The Department of Medicine, University of Cambridge School of Clinical MedicineCambridgeUnited Kingdom,Cambridge Institute of Therapeutic Immunology & Infectious Disease, Jeffrey Cheah Biomedical Centre Cambridge Biomedical CampusCambridgeUnited Kingdom
| | - Michael A Calderwood
- Center for Cancer Systems Biology (CCSB), Dana-Farber Cancer InstituteBostonUnited States,Department of Genetics, Blavatnik Institute, Harvard Medical SchoolBostonUnited States,Department of Cancer Biology, Dana-Farber Cancer InstituteBostonUnited States
| | - Jyoti Choudhary
- Functional Proteomics, Division of Cancer Biology, Institute of Cancer ResearchLondonUnited Kingdom
| | - Simon Clare
- Wellcome Trust Sanger InstituteHinxtonUnited Kingdom
| | | | - Giorgia Santilli
- Molecular Immunology Unit, UCL Great Ormond Street Institute of Child HealthLondonUnited Kingdom
| | - Alex Bateman
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Trust Genome CampusHinxtonUnited Kingdom
| | - Kenneth GC Smith
- The Department of Medicine, University of Cambridge School of Clinical MedicineCambridgeUnited Kingdom,Cambridge Institute of Therapeutic Immunology & Infectious Disease, Jeffrey Cheah Biomedical Centre Cambridge Biomedical CampusCambridgeUnited Kingdom
| | - Francesca Magnani
- Department of Biology and Biotechnology, University of PaviaPaviaItaly
| | - David C Thomas
- Department of Immunology and Inflammation, Centre for Inflammatory Disease, Imperial College LondonLondonUnited Kingdom
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12
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Loesch A. On P2X receptors in the brain: microvessels. Dedicated to the memory of the late Professor Geoffrey Burnstock (1929-2020). Cell Tissue Res 2021; 384:577-588. [PMID: 33755804 DOI: 10.1007/s00441-021-03411-0] [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: 10/27/2020] [Accepted: 01/01/2021] [Indexed: 12/13/2022]
Abstract
This tribute article presents selected immunocytochemical and transmission electron microscope data on the location of ATP-gated P2X receptor in the rat brain, as studied in the 1990s in Prof G. Burnstock's laboratory at University College London. There are examples of immuno-ultrastructural findings and introductory information about pre- and post-synaptic location of P2X receptors in the rat cerebellum and endocrine hypothalamus to support the concept of purinergic transmission in the central nervous system. Then findings of diverse immunoreactivity for P2X1, P2X2, P2X4, and P2X6 receptors associated with brain microvessels are shown, including vascular endothelium and pericytes as well as perivascular astrocytes and neuronal components. These findings imply the involvement of P2X receptors and hence purinergic signalling in the neurovascular unit, at least in microvessels in the rat cerebellum and hypothalamic paraventricular and supraoptic nuclei examined here. Various aspects of P2X receptors in brain microvessels are discussed.
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Affiliation(s)
- Andrzej Loesch
- Centre for Rheumatology and Connective Tissue Diseases, Division of Medicine, University College London Medical School, Royal Free Campus, London, UK.
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13
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Increased surface P2X4 receptor regulates anxiety and memory in P2X4 internalization-defective knock-in mice. Mol Psychiatry 2021; 26:629-644. [PMID: 31911635 DOI: 10.1038/s41380-019-0641-8] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Revised: 12/10/2019] [Accepted: 12/12/2019] [Indexed: 12/20/2022]
Abstract
ATP signaling and surface P2X4 receptors are upregulated selectively in neurons and/or glia in various CNS disorders including anxiety, chronic pain, epilepsy, ischemia, and neurodegenerative diseases. However, the cell-specific functions of P2X4 in pathological contexts remain elusive. To elucidate P2X4 functions, we created a conditional transgenic knock-in P2X4 mouse line (Floxed P2X4mCherryIN) allowing the Cre activity-dependent genetic swapping of the internalization motif of P2X4 by the fluorescent mCherry protein to prevent constitutive endocytosis of P2X4. By combining molecular, cellular, electrophysiological, and behavioral approaches, we characterized two distinct knock-in mouse lines expressing noninternalized P2X4mCherryIN either exclusively in excitatory forebrain neurons or in all cells natively expressing P2X4. The genetic substitution of wild-type P2X4 by noninternalized P2X4mCherryIN in both knock-in mouse models did not alter the sparse distribution and subcellular localization of P2X4 but increased the number of P2X4 receptors at the surface of the targeted cells mimicking the pathological increased surface P2X4 state. Increased surface P2X4 density in the hippocampus of knock-in mice altered LTP and LTD plasticity phenomena at CA1 synapses without affecting basal excitatory transmission. Moreover, these cellular events translated into anxiolytic effects and deficits in spatial memory. Our results show that increased surface density of neuronal P2X4 contributes to synaptic deficits and alterations in anxiety and memory functions consistent with the implication of P2X4 in neuropsychiatric and neurodegenerative disorders. Furthermore, these conditional P2X4mCherryIN knock-in mice will allow exploring the cell-specific roles of P2X4 in various physiological and pathological contexts.
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14
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Implication of Neuronal Versus Microglial P2X4 Receptors in Central Nervous System Disorders. Neurosci Bull 2020; 36:1327-1343. [PMID: 32889635 DOI: 10.1007/s12264-020-00570-y] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Accepted: 05/06/2020] [Indexed: 02/08/2023] Open
Abstract
The P2X4 receptor (P2X4) is an ATP-gated cation channel that is highly permeable to Ca2+ and widely expressed in neuronal and glial cell types throughout the central nervous system (CNS). A growing body of evidence indicates that P2X4 plays key roles in numerous central disorders. P2X4 trafficking is highly regulated and consequently in normal situations, P2X4 is present on the plasma membrane at low density and found mostly within intracellular endosomal/lysosomal compartments. An increase in the de novo expression and/or surface density of P2X4 has been observed in microglia and/or neurons during pathological states. This review aims to summarize knowledge on P2X4 functions in CNS disorders and provide some insights into the relative contributions of neuronal and glial P2X4 in pathological contexts. However, determination of the cell-specific functions of P2X4 along with its intracellular and cell surface roles remain to be elucidated before its potential as a therapeutic target in multiple disorders can be defined.
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15
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Montilla A, Mata GP, Matute C, Domercq M. Contribution of P2X4 Receptors to CNS Function and Pathophysiology. Int J Mol Sci 2020; 21:E5562. [PMID: 32756482 PMCID: PMC7432758 DOI: 10.3390/ijms21155562] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 07/30/2020] [Accepted: 07/31/2020] [Indexed: 12/11/2022] Open
Abstract
The release and extracellular action of ATP are a widespread mechanism for cell-to-cell communication in living organisms through activation of P2X and P2Y receptors expressed at the cell surface of most tissues, including the nervous system. Among ionototropic receptors, P2X4 receptors have emerged in the last decade as a potential target for CNS disorders such as epilepsy, ischemia, chronic pain, anxiety, multiple sclerosis and neurodegenerative diseases. However, the role of P2X4 receptor in each pathology ranges from beneficial to detrimental, although the mechanisms are still mostly unknown. P2X4 is expressed at low levels in CNS cells including neurons and glial cells. In normal conditions, P2X4 activation contributes to synaptic transmission and synaptic plasticity. Importantly, one of the genes present in the transcriptional program of myeloid cell activation is P2X4. Microglial P2X4 upregulation, the P2X4+ state of microglia, seems to be common in most acute and chronic neurodegenerative diseases associated with inflammation. In this review, we summarize knowledge about the role of P2X4 receptors in the CNS physiology and discuss potential pitfalls and open questions about the therapeutic potential of blocking or potentiation of P2X4 for different pathologies.
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Affiliation(s)
- Alejandro Montilla
- Department of Neuroscience, University of the Basque Country (UPV/EHU), Achucarro Basque Center for Neuroscience and Instituto de Salud Carlos III, Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), 48940 Leioa, Spain
| | - Gilda Paloma Mata
- Department of Neuroscience, University of the Basque Country (UPV/EHU), Achucarro Basque Center for Neuroscience and Instituto de Salud Carlos III, Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), 48940 Leioa, Spain
| | - Carlos Matute
- Department of Neuroscience, University of the Basque Country (UPV/EHU), Achucarro Basque Center for Neuroscience and Instituto de Salud Carlos III, Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), 48940 Leioa, Spain
| | - Maria Domercq
- Department of Neuroscience, University of the Basque Country (UPV/EHU), Achucarro Basque Center for Neuroscience and Instituto de Salud Carlos III, Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), 48940 Leioa, Spain
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16
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Lara R, Adinolfi E, Harwood CA, Philpott M, Barden JA, Di Virgilio F, McNulty S. P2X7 in Cancer: From Molecular Mechanisms to Therapeutics. Front Pharmacol 2020; 11:793. [PMID: 32581786 PMCID: PMC7287489 DOI: 10.3389/fphar.2020.00793] [Citation(s) in RCA: 102] [Impact Index Per Article: 25.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Accepted: 05/13/2020] [Indexed: 12/18/2022] Open
Abstract
P2X7 is a transmembrane receptor expressed in multiple cell types including neurons, dendritic cells, macrophages, monocytes, B and T cells where it can drive a wide range of physiological responses from pain transduction to immune response. Upon activation by its main ligand, extracellular ATP, P2X7 can form a nonselective channel for cations to enter the cell. Prolonged activation of P2X7, via high levels of extracellular ATP over an extended time period can lead to the formation of a macropore, leading to depolarization of the plasma membrane and ultimately to cell death. Thus, dependent on its activation state, P2X7 can either drive cell survival and proliferation, or induce cell death. In cancer, P2X7 has been shown to have a broad range of functions, including playing key roles in the development and spread of tumor cells. It is therefore unsurprising that P2X7 has been reported to be upregulated in several malignancies. Critically, ATP is present at high extracellular concentrations in the tumor microenvironment (TME) compared to levels observed in normal tissues. These high levels of ATP should present a survival challenge for cancer cells, potentially leading to constitutive receptor activation, prolonged macropore formation and ultimately to cell death. Therefore, to deliver the proven advantages for P2X7 in driving tumor survival and metastatic potential, the P2X7 macropore must be tightly controlled while retaining other functions. Studies have shown that commonly expressed P2X7 splice variants, distinct SNPs and post-translational receptor modifications can impair the capacity of P2X7 to open the macropore. These receptor modifications and potentially others may ultimately protect cancer cells from the negative consequences associated with constitutive activation of P2X7. Significantly, the effects of both P2X7 agonists and antagonists in preclinical tumor models of cancer demonstrate the potential for agents modifying P2X7 function, to provide innovative cancer therapies. This review summarizes recent advances in understanding of the structure and functions of P2X7 and how these impact P2X7 roles in cancer progression. We also review potential therapeutic approaches directed against P2X7.
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Affiliation(s)
- Romain Lara
- Biosceptre (UK) Limited, Cambridge, United Kingdom
| | - Elena Adinolfi
- Department of Medical Sciences, University of Ferrara, Ferrara, Italy
| | - Catherine A Harwood
- Centre for Cell Biology and Cutaneous Research, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, United Kingdom
| | - Mike Philpott
- Centre for Cutaneous Research, Blizard Institute, Bart's & The London School of Medicine and Dentistry, Queen Mary University of London, London, United Kingdom
| | | | - Francesco Di Virgilio
- Department of Morphology, Surgery and Experimental Medicine, Section of Pathology, Oncology and Experimental Biology, University of Ferrara, Ferrara, Italy
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17
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Datta G, Miller NM, Afghah Z, Geiger JD, Chen X. HIV-1 gp120 Promotes Lysosomal Exocytosis in Human Schwann Cells. Front Cell Neurosci 2019; 13:329. [PMID: 31379513 PMCID: PMC6650616 DOI: 10.3389/fncel.2019.00329] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Accepted: 07/03/2019] [Indexed: 12/31/2022] Open
Abstract
Human immunodeficiency virus type 1 (HIV-1) associated neuropathy is the most common neurological complication of HIV-1, with debilitating pain affecting the quality of life. HIV-1 gp120 plays an important role in the pathogenesis of HIV neuropathy via direct neurotoxic effects or indirect pro-inflammatory responses. Studies have shown that gp120-induced release of mediators from Schwann cells induce CCR5-dependent DRG neurotoxicity, however, CCR5 antagonists failed to improve pain in HIV- infected individuals. Thus, there is an urgent need for a better understanding of neuropathic pain pathogenesis and developing effective therapeutic strategies. Because lysosomal exocytosis in Schwann cells is an indispensable process for regulating myelination and demyelination, we determined the extent to which gp120 affected lysosomal exocytosis in human Schwann cells. We demonstrated that gp120 promoted the movement of lysosomes toward plasma membranes, induced lysosomal exocytosis, and increased the release of ATP into the extracellular media. Mechanistically, we demonstrated lysosome de-acidification, and activation of P2X4 and VNUT to underlie gp120-induced lysosome exocytosis. Functionally, we demonstrated that gp120-induced lysosome exocytosis and release of ATP from Schwann cells leads to increases in intracellular calcium and generation of cytosolic reactive oxygen species in DRG neurons. Our results suggest that gp120-induced lysosome exocytosis and release of ATP from Schwann cells and DRG neurons contribute to the pathogenesis of HIV-1 associated neuropathy.
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Affiliation(s)
- Gaurav Datta
- Department of Biomedical Sciences, University of North Dakota School of Medicine and Health Sciences, Grand Forks, ND, United States
| | - Nicole M Miller
- Department of Biomedical Sciences, University of North Dakota School of Medicine and Health Sciences, Grand Forks, ND, United States
| | - Zahra Afghah
- Department of Biomedical Sciences, University of North Dakota School of Medicine and Health Sciences, Grand Forks, ND, United States
| | - Jonathan D Geiger
- Department of Biomedical Sciences, University of North Dakota School of Medicine and Health Sciences, Grand Forks, ND, United States
| | - Xuesong Chen
- Department of Biomedical Sciences, University of North Dakota School of Medicine and Health Sciences, Grand Forks, ND, United States
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18
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Franco M, Pérez-Méndez O, Kulthinee S, Navar LG. Integration of purinergic and angiotensin II receptor function in renal vascular responses and renal injury in angiotensin II-dependent hypertension. Purinergic Signal 2019; 15:277-285. [PMID: 31183668 PMCID: PMC6635571 DOI: 10.1007/s11302-019-09662-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Accepted: 05/30/2019] [Indexed: 12/24/2022] Open
Abstract
Glomerular arteriolar vasoconstriction and tubulointerstitial injury are observed before glomerular damage occurs in models of hypertension. High interstitial ATP concentrations, caused by the increase in arterial pressure, alter renal mechanisms involved in the long-term control of blood pressure, autoregulation of glomerular filtration rate and blood flow, tubuloglomerular feedback (TGF) responses, and sodium excretion. Elevated ATP concentrations and augmented expression of P2X receptors have been demonstrated under a genetic background or induction of hypertension with vasoconstrictor peptides. In addition to the alterations of the microcirculation in the hypertensive kidney, the vascular actions of elevated intrarenal angiotensin II levels may be mitigated by the administration of broad purinergic P2 antagonists or specific P2Y12, P2X1, and P2X7 receptor antagonists. Furthermore, the prevention of tubulointerstitial infiltration with immunosuppressor compounds reduces the development of salt-sensitive hypertension, indicating that tubulointerstitial inflammation is essential for the development and maintenance of hypertension. Inflammatory cells also express abundant purinergic receptors, and their activation by ATP induces cytokine and growth factor release that in turn contributes to augment tubulointerstitial inflammation. Collectively, the evidence suggests a pathophysiological activation of purinergic P2 receptors in angiotensin-dependent hypertension. Coexistent increases in intrarenal angiotensin II and activates Ang II AT1 receptors, which interacts with over-activated purinergic receptors in a complex manner, suggesting convergence of their post-receptor signaling processes.
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Affiliation(s)
- Martha Franco
- Department of Nephrology, Renal Pathophysiology Laboratory, Instituto Nacional de Cardiología “Ignacio Chávez”, Juan Badiano No.1, 14080 Mexico City, DF Mexico
| | - Oscar Pérez-Méndez
- Department Molecular Biology, Instituto Nacional de Cardiología “Ignacio Chávez”, Mexico City, Mexico
| | - Supaporn Kulthinee
- Department of Physiology and Hypertension and Renal Center, Tulane University School of Medicine, New Orleans, LA USA
- Department of Cardiovascular and Thoracic Technology, Chulabhorn International College of Medicine, Thammasat University, Rangsit, Pathum Thani Thailand
| | - L. Gabriel Navar
- Department of Physiology and Hypertension and Renal Center, Tulane University School of Medicine, New Orleans, LA USA
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19
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Winkelmann VE, Thompson KE, Neuland K, Jaramillo AM, Fois G, Schmidt H, Wittekindt OH, Han W, Tuvim MJ, Dickey BF, Dietl P, Frick M. Inflammation-induced upregulation of P2X 4 expression augments mucin secretion in airway epithelia. Am J Physiol Lung Cell Mol Physiol 2018; 316:L58-L70. [PMID: 30358443 DOI: 10.1152/ajplung.00157.2018] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Mucus clearance provides an essential innate defense mechanism to keep the airways and lungs free of particles and pathogens. Baseline and stimulated mucin secretion from secretory airway epithelial cells need to be tightly regulated to prevent mucus hypersecretion and mucus plugging of the airways. It is well established that extracellular ATP is a potent stimulus for regulated mucus secretion. Previous studies revealed that ATP acts via metabotropic P2Y2 purinoreceptors on goblet cells. Extracellular ATP, however, is also a potent agonist for ionotropic P2X purinoreceptors. Expression of several P2X isoforms has been reported in airways, but cell type-specific expression and the function thereof remained elusive. With this study, we now provide evidence that P2X4 is the predominant P2X isoform expressed in secretory airway epithelial cells. After IL-13 treatment of either human primary tracheal epithelial cells or mice, P2X4 expression is upregulated in vitro and in vivo under conditions of chronic inflammation, mucous metaplasia, and hyperplasia. Upregulation of P2X4 is strongest in MUC5AC-positive goblet cells. Moreover, activation of P2X4 by extracellular ATP augments intracellular Ca2+ signals and mucin secretion, whereas Ca2+ signals and mucin secretion are dampened by inhibition of P2X4 receptors. These data provide new insights into the purinergic regulation of mucin secretion and add to the emerging picture that P2X receptors modulate exocytosis of large secretory organelles and secretion of macromolecular vesicle cargo.
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Affiliation(s)
| | - Kristin E Thompson
- Centre de Recherche Saint-Antoine, INSERM, Université Pierre et Marie Curie-Université Paris 06, Sorbonne Universités, Paris , France
| | - Kathrin Neuland
- Institute of General Physiology, Ulm University , Ulm , Germany
| | - Ana M Jaramillo
- Department of Pulmonary Medicine, MD Anderson Cancer Center , Houston, Texas
| | - Giorgio Fois
- Institute of General Physiology, Ulm University , Ulm , Germany
| | - Hanna Schmidt
- Institute of General Physiology, Ulm University , Ulm , Germany
| | | | - Wei Han
- Department of Pulmonary Medicine, MD Anderson Cancer Center , Houston, Texas
| | - Michael J Tuvim
- Department of Pulmonary Medicine, MD Anderson Cancer Center , Houston, Texas
| | - Burton F Dickey
- Department of Pulmonary Medicine, MD Anderson Cancer Center , Houston, Texas
| | - Paul Dietl
- Institute of General Physiology, Ulm University , Ulm , Germany
| | - Manfred Frick
- Institute of General Physiology, Ulm University , Ulm , Germany
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20
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Fois G, Föhr KJ, Kling C, Fauler M, Wittekindt OH, Dietl P, Frick M. P2X 4 receptor re-sensitization depends on a protonation/deprotonation cycle mediated by receptor internalization and recycling. J Physiol 2018; 596:4893-4907. [PMID: 30144063 DOI: 10.1113/jp275448] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Accepted: 08/21/2018] [Indexed: 12/28/2022] Open
Abstract
KEY POINTS Re-sensitization of P2X4 receptors depends on a protonation/de-protonation cycle Protonation and de-protonation of the receptors is achieved by internalization and recycling of P2X4 receptors via acidic compartments Protonation and de-protonation occurs at critical histidine residues within the extracellular loop of P2X4 receptors Re-sensitization is blocked in the presence of the receptor agonist ATP ABSTRACT: P2X4 receptors are members of the P2X receptor family of cation-permeable, ligand-gated ion channels that open in response to the binding of extracellular ATP. P2X4 receptors are implicated in a variety of biological processes, including cardiac function, cell death, pain sensation and immune responses. These physiological functions depend on receptor activation on the cell surface. Receptor activation is followed by receptor desensitization and deactivation upon removal of ATP. Subsequent re-sensitization is required to return the receptor into its resting state. Desensitization and re-sensitization are therefore crucial determinants of P2X receptor signal transduction and responsiveness to ATP. However, the molecular mechanisms controlling desensitization and re-sensitization are not fully understood. In the present study, we provide evidence that internalization and recycling via acidic compartments is essential for P2X4 receptor re-sensitization. Re-sensitization depends on a protonation/de-protonation cycle of critical histidine residues within the extracellular loop of P2X4 receptors that is mediated by receptor internalization and recycling. Interestingly, re-sensitization under acidic conditions is completely revoked by receptor agonist ATP. Our data support the physiological importance of the unique subcellular distribution of P2X4 receptors that is predominantly found within acidic compartments. Based on these findings, we suggest that recycling of P2X4 receptors regulates the cellular responsiveness in the sustained presence of ATP.
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Affiliation(s)
| | - Karl J Föhr
- Department of Anesthesiology, University of Ulm, Ulm, Germany
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21
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Young CNJ, Górecki DC. P2RX7 Purinoceptor as a Therapeutic Target-The Second Coming? Front Chem 2018; 6:248. [PMID: 30003075 PMCID: PMC6032550 DOI: 10.3389/fchem.2018.00248] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Accepted: 06/08/2018] [Indexed: 12/22/2022] Open
Abstract
The P2RX7 receptor is a unique member of a family of extracellular ATP (eATP)-gated ion channels expressed in immune cells, where its activation triggers the inflammatory cascade. Therefore, P2RX7 has been long investigated as a target in the treatment of infectious and inflammatory diseases. Subsequently, P2RX7 signaling has been documented in other physiological and pathological processes including pain, CNS and psychiatric disorders and cancer. As a result, a range of P2RX7 antagonists have been developed and trialed. Interestingly, the recent crystallization of mammalian and chicken receptors revealed that most widely-used antagonists may bind a unique allosteric site. The availability of crystal structures allows rational design of improved antagonists and modeling of binding sites of the known or presumed inhibitors. However, several unanswered questions limit the cogent development of P2RX7 therapies. Firstly, this receptor functions as an ion channel, but its chronic stimulation by high eATP causes opening of the non-selective large pore (LP), which can trigger cell death. Not only the molecular mechanism of LP opening is still not fully understood but its function(s) are also unclear. Furthermore, how can tumor cells take advantage of P2RX7 for growth and spread and yet survive overexpression of potentially cytotoxic LP in the eATP-rich environment? The recent discovery of the feedback loop, wherein the LP-evoked release of active MMP-2 triggers the receptor cleavage, provided one explanation. Another mechanism might be that of cancer cells expressing a structurally altered P2RX7 receptor, devoid of the LP function. Exploiting such mechanisms should lead to the development of new, less toxic anticancer treatments. Notably, targeted inhibition of P2RX7 is crucial as its global blockade reduces the immune and inflammatory responses, which have important anti-tumor effects in some types of malignancies. Therefore, another novel approach is the synthesis of tissue/cell specific P2RX7 antagonists. Progress has been aided by the development of p2rx7 knockout mice and new conditional knock-in and knock-out models are being created. In this review, we seek to summarize the recent advances in our understanding of molecular mechanisms of receptor activation and inhibition, which cause its re-emergence as an important therapeutic target. We also highlight the key difficulties affecting this development.
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Affiliation(s)
- Chris N. J. Young
- Molecular Medicine Laboratory, Institute of Biomedical and Biomolecular Sciences, School of Pharmacy and Biomedical Sciences, University of Portsmouth, Portsmouth, United Kingdom
- Faculty of Health and Life Sciences, The School of Allied Health Sciences, De Montfort University, Leicester, United Kingdom
| | - Dariusz C. Górecki
- Molecular Medicine Laboratory, Institute of Biomedical and Biomolecular Sciences, School of Pharmacy and Biomedical Sciences, University of Portsmouth, Portsmouth, United Kingdom
- The General Karol Kaczkowski Military Institute of Hygiene and Epidemiology, Warsaw, Poland
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22
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Xu F, Yang J, Lu F, Liu R, Zheng J, Zhang J, Cui W, Wang C, Zhou W, Wang Q, Chen X, Chen J. Fast Green FCF Alleviates Pain Hypersensitivity and Down-Regulates the Levels of Spinal P2X4 Expression and Pro-inflammatory Cytokines in a Rodent Inflammatory Pain Model. Front Pharmacol 2018; 9:534. [PMID: 29875666 PMCID: PMC5974208 DOI: 10.3389/fphar.2018.00534] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Accepted: 05/03/2018] [Indexed: 12/13/2022] Open
Abstract
Fast Green FCF (FGF), a biocompatible dye, recently drew attention as a potential drug to treat amyloid-deposit diseases due to its effects against amyloid fibrillogenesis in vitro and a high degree of safety. However, its role in inflammatory pain is unknown. Our study aimed to investigate the effect of FGF in the inflammatory pain model induced by complete Freund’s adjuvant (CFA) and to identify the associated mechanisms. We found that systemic administration of FGF reversed mechanical and thermal pain hypersensitivity evoked by CFA in a dose-dependent manner. FGF treatment decreased purinergic spinal P2X4 expression in the spinal cord of CFA-inflamed mice. FGF also down-regulated spinal and peripheral pro-inflammatory cytokines [tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and interleukin-6 (IL-6)], but did not alter the spinal level of nerve growth factor (NGF) or brain-derived neurotrophic factor (BDNF). In conclusion, our results suggest the potential of FGF for controlling the progress of inflammatory pain.
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Affiliation(s)
- Fang Xu
- Ningbo Key Laboratory of Behavioral Neuroscience, Zhejiang Provincial Key Laboratory of Pathophysiology, The Medical School of Ningbo University, Ningbo University, Ningbo, China
| | - Jing Yang
- Ningbo Key Laboratory of Behavioral Neuroscience, Zhejiang Provincial Key Laboratory of Pathophysiology, The Medical School of Ningbo University, Ningbo University, Ningbo, China
| | - Fan Lu
- Ningbo Key Laboratory of Behavioral Neuroscience, Zhejiang Provincial Key Laboratory of Pathophysiology, The Medical School of Ningbo University, Ningbo University, Ningbo, China
| | - Rongjun Liu
- Ningbo Key Laboratory of Behavioral Neuroscience, Zhejiang Provincial Key Laboratory of Pathophysiology, The Medical School of Ningbo University, Ningbo University, Ningbo, China
| | - Jinwei Zheng
- Department of Anesthesiology, Ningbo No. 2 Hospital, Ningbo, China
| | - Junfang Zhang
- Ningbo Key Laboratory of Behavioral Neuroscience, Zhejiang Provincial Key Laboratory of Pathophysiology, The Medical School of Ningbo University, Ningbo University, Ningbo, China
| | - Wei Cui
- Ningbo Key Laboratory of Behavioral Neuroscience, Zhejiang Provincial Key Laboratory of Pathophysiology, The Medical School of Ningbo University, Ningbo University, Ningbo, China
| | - Chuang Wang
- Ningbo Key Laboratory of Behavioral Neuroscience, Zhejiang Provincial Key Laboratory of Pathophysiology, The Medical School of Ningbo University, Ningbo University, Ningbo, China
| | - Wenhua Zhou
- Ningbo Key Laboratory of Behavioral Neuroscience, Zhejiang Provincial Key Laboratory of Pathophysiology, The Medical School of Ningbo University, Ningbo University, Ningbo, China
| | - Qinwen Wang
- Ningbo Key Laboratory of Behavioral Neuroscience, Zhejiang Provincial Key Laboratory of Pathophysiology, The Medical School of Ningbo University, Ningbo University, Ningbo, China
| | - Xiaowei Chen
- Ningbo Key Laboratory of Behavioral Neuroscience, Zhejiang Provincial Key Laboratory of Pathophysiology, The Medical School of Ningbo University, Ningbo University, Ningbo, China
| | - Junping Chen
- Department of Anesthesiology, Ningbo No. 2 Hospital, Ningbo, China
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23
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Liu HY, Chen WL, Ober CK, Daniel S. Biologically Complex Planar Cell Plasma Membranes Supported on Polyelectrolyte Cushions Enhance Transmembrane Protein Mobility and Retain Native Orientation. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:1061-1072. [PMID: 29020444 DOI: 10.1021/acs.langmuir.7b02945] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Reconstituted supported lipid bilayers (SLB) are widely used as in vitro cell-surface models because they are compatible with a variety of surface-based analytical techniques. However, one of the challenges of using SLBs as a model of the cell surface is the limited complexity in membrane composition, including the incorporation of transmembrane proteins and lipid diversity that may impact the activity of those proteins. Additionally, it is challenging to preserve the transmembrane protein native orientation, function, and mobility in SLBs. Here, we leverage the interaction between cell plasma membrane vesicles and polyelectrolyte brushes to create planar bilayers from cell plasma membrane vesicles that have budded from the cell surface. This approach promotes the direct incorporation of membrane proteins and other species into the planar bilayer without using detergent or reconstitution and preserves membrane constituents. Furthermore, the structure of the polyelectrolyte brush serves as a cushion between the planar bilayer and rigid supporting surface, limiting the interaction of the cytosolic domains of membrane proteins with this surface. Single particle tracking was used to analyze the motion of GPI-linked yellow fluorescent proteins (GPI-YFP) and neon-green fused transmembrane P2X2 receptors (P2X2-neon) and shows that this platform retains over 75% mobility of multipass transmembrane proteins in its native membrane environment. An enzyme accessibility assay confirmed that the protein orientation is preserved and results in the extracellular domain facing toward the bulk phase and the cytosolic side facing the support. Because the platform presented here retains the complexity of the cell plasma membrane and preserves protein orientation and mobility, it is a better representative mimic of native cell surfaces, which may find many applications in biological assays aimed at understanding cell membrane phenomena.
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Affiliation(s)
- Han-Yuan Liu
- Robert F. Smith School of Chemical and Biomolecular Engineering, ‡Department of Material Science and Engineering, Cornell University , Ithaca, New York 14853, United States
| | - Wei-Liang Chen
- Robert F. Smith School of Chemical and Biomolecular Engineering, ‡Department of Material Science and Engineering, Cornell University , Ithaca, New York 14853, United States
| | - Christopher K Ober
- Robert F. Smith School of Chemical and Biomolecular Engineering, ‡Department of Material Science and Engineering, Cornell University , Ithaca, New York 14853, United States
| | - Susan Daniel
- Robert F. Smith School of Chemical and Biomolecular Engineering, ‡Department of Material Science and Engineering, Cornell University , Ithaca, New York 14853, United States
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24
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Sáez-Orellana F, Fuentes-Fuentes MC, Godoy PA, Silva-Grecchi T, Panes JD, Guzmán L, Yévenes GE, Gavilán J, Egan TM, Aguayo LG, Fuentealba J. P2X receptor overexpression induced by soluble oligomers of amyloid beta peptide potentiates synaptic failure and neuronal dyshomeostasis in cellular models of Alzheimer's disease. Neuropharmacology 2017; 128:366-378. [PMID: 29079292 DOI: 10.1016/j.neuropharm.2017.10.027] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2017] [Revised: 10/13/2017] [Accepted: 10/21/2017] [Indexed: 12/17/2022]
Abstract
The most common cause of dementia is Alzheimer's disease. The etiology of the disease is unknown, although considerable evidence suggests a critical role for the soluble oligomers of amyloid beta peptide (Aβ). Because Aβ increases the expression of purinergic receptors (P2XRs) in vitro and in vivo, we studied the functional correlation between long-term exposure to Aβ and the ability of P2XRs to modulate network synaptic tone. We used electrophysiological recordings and Ca2+ microfluorimetry to assess the effects of chronic exposure (24 h) to Aβ oligomers (0.5 μM) together with known inhibitors of P2XRs, such as PPADS and apyrase on synaptic function. Changes in the expression of P2XR were quantified using RT-qPCR. We observed changes in the expression of P2X1R, P2X7R and an increase in P2X2R; and also in protein levels in PC12 cells (143%) and hippocampal neurons (120%) with Aβ. In parallel, the reduction on the frequency and amplitude of mEPSCs (72% and 35%, respectively) were prevented by P2XR inhibition using a low PPADS concentration. Additionally, the current amplitude and intracellular Ca2+ signals evoked by extracellular ATP were increased (70% and 75%, respectively), suggesting an over activation of purinergic neurotransmission in cells pre-treated with Aβ. Taken together, our findings suggest that Aβ disrupts the main components of synaptic transmission at both pre- and post-synaptic sites, and induces changes in the expression of key P2XRs, especially P2X2R; changing the neuromodulator function of the purinergic tone that could involve the P2X2R as a key factor for cytotoxic mechanisms. These results identify novel targets for the treatment of dementia and other diseases characterized by increased purinergic transmission.
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Affiliation(s)
- Francisco Sáez-Orellana
- Neuroactive Compounds Screening Laboratory, Physiology Department, Biological Sciences Faculty, Universidad de Concepción, Concepción, Chile
| | - María C Fuentes-Fuentes
- Neuroactive Compounds Screening Laboratory, Physiology Department, Biological Sciences Faculty, Universidad de Concepción, Concepción, Chile
| | - Pamela A Godoy
- Neuroactive Compounds Screening Laboratory, Physiology Department, Biological Sciences Faculty, Universidad de Concepción, Concepción, Chile
| | - Tiare Silva-Grecchi
- Neuroactive Compounds Screening Laboratory, Physiology Department, Biological Sciences Faculty, Universidad de Concepción, Concepción, Chile
| | - Jessica D Panes
- Neuroactive Compounds Screening Laboratory, Physiology Department, Biological Sciences Faculty, Universidad de Concepción, Concepción, Chile
| | - Leonardo Guzmán
- Molecular Neurobiology Laboratory, Physiology Department, Biological Sciences Faculty, Universidad de Concepción, Concepción, Chile
| | - Gonzalo E Yévenes
- Neuropharmacology Laboratory, Physiology Department, Biological Sciences Faculty, Universidad de Concepción, Concepción, Chile
| | - Javiera Gavilán
- Neuroactive Compounds Screening Laboratory, Physiology Department, Biological Sciences Faculty, Universidad de Concepción, Concepción, Chile
| | - Terrance M Egan
- Department of Pharmacology and Physiology, School of Medicine, Saint Louis University, St. Louis, MO, USA
| | - Luis G Aguayo
- Neuropharmacology Laboratory, Physiology Department, Biological Sciences Faculty, Universidad de Concepción, Concepción, Chile
| | - Jorge Fuentealba
- Neuroactive Compounds Screening Laboratory, Physiology Department, Biological Sciences Faculty, Universidad de Concepción, Concepción, Chile.
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25
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Di Virgilio F, Dal Ben D, Sarti AC, Giuliani AL, Falzoni S. The P2X7 Receptor in Infection and Inflammation. Immunity 2017; 47:15-31. [PMID: 28723547 DOI: 10.1016/j.immuni.2017.06.020] [Citation(s) in RCA: 797] [Impact Index Per Article: 113.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Revised: 02/14/2017] [Accepted: 06/27/2017] [Indexed: 12/11/2022]
Abstract
Adenosine triphosphate (ATP) accumulates at sites of tissue injury and inflammation. Effects of extracellular ATP are mediated by plasma membrane receptors named P2 receptors (P2Rs). The P2R most involved in inflammation and immunity is the P2X7 receptor (P2X7R), expressed by virtually all cells of innate and adaptive immunity. P2X7R mediates NLRP3 inflammasome activation, cytokine and chemokine release, T lymphocyte survival and differentiation, transcription factor activation, and cell death. Ten human P2RX7 gene splice variants and several SNPs that produce complex haplotypes are known. The P2X7R is a potent stimulant of inflammation and immunity and a promoter of cancer cell growth. This makes P2X7R an appealing target for anti-inflammatory and anti-cancer therapy. However, an in-depth knowledge of its structure and of the associated signal transduction mechanisms is needed for an effective therapeutic development.
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Affiliation(s)
- Francesco Di Virgilio
- Department of Morphology, Surgery and Experimental Medicine, University of Ferrara, Ferrara, Italy.
| | - Diego Dal Ben
- School of Pharmacy, University of Camerino, Camerino, Italy
| | - Alba Clara Sarti
- Department of Morphology, Surgery and Experimental Medicine, University of Ferrara, Ferrara, Italy
| | - Anna Lisa Giuliani
- Department of Morphology, Surgery and Experimental Medicine, University of Ferrara, Ferrara, Italy
| | - Simonetta Falzoni
- Department of Morphology, Surgery and Experimental Medicine, University of Ferrara, Ferrara, Italy
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26
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Modulation of Central Synapses by Astrocyte-Released ATP and Postsynaptic P2X Receptors. Neural Plast 2017; 2017:9454275. [PMID: 28845311 PMCID: PMC5563405 DOI: 10.1155/2017/9454275] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Accepted: 07/10/2017] [Indexed: 01/14/2023] Open
Abstract
Communication between neuronal and glial cells is important for neural plasticity. P2X receptors are ATP-gated cation channels widely expressed in the brain where they mediate action of extracellular ATP released by neurons and/or glia. Recent data show that postsynaptic P2X receptors underlie slow neuromodulatory actions rather than fast synaptic transmission at brain synapses. Here, we review these findings with a particular focus on the release of ATP by astrocytes and the diversity of postsynaptic P2X-mediated modulation of synaptic strength and plasticity in the CNS.
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27
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P2X7 receptor cross-talk regulates ATP-induced pannexin 1 internalization. Biochem J 2017; 474:2133-2144. [PMID: 28495860 DOI: 10.1042/bcj20170257] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Revised: 05/04/2017] [Accepted: 05/10/2017] [Indexed: 12/12/2022]
Abstract
In the nervous system, extracellular ATP levels transiently increase in physiological and pathophysiological circumstances, effecting key signalling pathways in plasticity and inflammation through purinergic receptors. Pannexin 1 (Panx1) forms ion- and metabolite-permeable channels that mediate ATP release and are particularly enriched in the nervous system. Our recent study demonstrated that elevation of extracellular ATP triggers Panx1 internalization in a concentration- and time-dependent manner. Notably, this effect was sensitive to inhibition of ionotropic P2X7 purinergic receptors (P2X7Rs). Here, we report our novel findings from the detailed investigation of the mechanism underlying P2X7R-Panx1 cross-talk in ATP-stimulated internalization. We demonstrate that extracellular ATP triggers and is required for the clustering of P2X7Rs and Panx1 on Neuro2a cells through an extracellular physical interaction with the Panx1 first extracellular loop (EL1). Importantly, disruption of P2X7R-Panx1 clustering by mutation of tryptophan 74 within the Panx1 EL1 inhibits Panx1 internalization. Notably, P2X7R-Panx1 clustering and internalization are independent of P2X7R-associated intracellular signalling pathways (Ca2+ influx and Src activation). Further analysis revealed that cholesterol is required for ATP-stimulated P2X7R-Panx1 clustering at the cell periphery. Taken together, our data suggest that extracellular ATP induces and is required for Panx1 EL1-mediated, cholesterol-dependent P2X7R-Panx1 clustering and endocytosis. These findings have important implications for understanding the role of Panx1 in the nervous system and provide important new insights into Panx1-P2X7R cross-talk.
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28
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Stokes L, Layhadi JA, Bibic L, Dhuna K, Fountain SJ. P2X4 Receptor Function in the Nervous System and Current Breakthroughs in Pharmacology. Front Pharmacol 2017; 8:291. [PMID: 28588493 PMCID: PMC5441391 DOI: 10.3389/fphar.2017.00291] [Citation(s) in RCA: 100] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Accepted: 05/05/2017] [Indexed: 12/18/2022] Open
Abstract
Adenosine 5′-triphosphate is a well-known extracellular signaling molecule and neurotransmitter known to activate purinergic P2X receptors. Information has been elucidated about the structure and gating of P2X channels following the determination of the crystal structure of P2X4 (zebrafish), however, there is still much to discover regarding the role of this receptor in the central nervous system (CNS). In this review we provide an overview of what is known about P2X4 expression in the CNS and discuss evidence for pathophysiological roles in neuroinflammation and neuropathic pain. Recent advances in the development of pharmacological tools including selective antagonists (5-BDBD, PSB-12062, BX430) and positive modulators (ivermectin, avermectins, divalent cations) of P2X4 will be discussed.
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Affiliation(s)
- Leanne Stokes
- School of Pharmacy, University of East Anglia, Norwich Research ParkNorwich, United Kingdom.,School of Biomedical and Health Sciences, RMIT University, BundooraVIC, Australia
| | - Janice A Layhadi
- Biomedical Research Centre, School of Biological Sciences, University of East AngliaNorwich, United Kingdom
| | - Lucka Bibic
- School of Pharmacy, University of East Anglia, Norwich Research ParkNorwich, United Kingdom
| | - Kshitija Dhuna
- School of Biomedical and Health Sciences, RMIT University, BundooraVIC, Australia
| | - Samuel J Fountain
- Biomedical Research Centre, School of Biological Sciences, University of East AngliaNorwich, United Kingdom
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29
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Lalo U, Pankratov Y. Exploring the Ca 2+-dependent synaptic dynamics in vibro-dissociated cells. Cell Calcium 2017; 64:91-101. [PMID: 28143648 DOI: 10.1016/j.ceca.2017.01.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2016] [Revised: 01/15/2017] [Accepted: 01/16/2017] [Indexed: 12/18/2022]
Abstract
Dynamic alteration of the synaptic strength is one of the most important processes occurring in the nervous system. Combination of electrophysiology, confocal imaging and molecular biology led to significant advances in this research field. Yet, a progress in this area, in particular in studies of changes in the quantal behavior of central synapses and impact of glial cells on individual synapses, is hampered by technical difficulties of resolving small quantal synaptic currents. In this paper we will show how the technique of non-enzymatic vibro-dissociation, which enables to isolate living neurons avoiding artifacts of cell culture and preserving functional synapse, can be used to obtain a valuable information on fine details and mechanisms of synaptic plasticity. In particular, we will describe our recent results on Ca2+-dependent modulation of the postsynaptic AMPA and NMDA receptors in the individual synaptic boutons.
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Affiliation(s)
- Ulyana Lalo
- The University of Warwick, School of Life Sciences, Coventry, UK
| | - Yuriy Pankratov
- The University of Warwick, School of Life Sciences, Coventry, UK; School of Life Sciences, Immanuel Kant Baltic Federal University, 2 Universitetskaya str., Kaliningrad, Russia.
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30
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ATP from synaptic terminals and astrocytes regulates NMDA receptors and synaptic plasticity through PSD-95 multi-protein complex. Sci Rep 2016; 6:33609. [PMID: 27640997 PMCID: PMC5027525 DOI: 10.1038/srep33609] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Accepted: 08/30/2016] [Indexed: 12/13/2022] Open
Abstract
Recent studies highlighted the importance of astrocyte-secreted molecules, such as ATP, for the slow modulation of synaptic transmission in central neurones. Biophysical mechanisms underlying the impact of gliotransmitters on the strength of individual synapse remain, however, unclear. Here we show that purinergic P2X receptors can bring significant contribution to the signalling in the individual synaptic boutons. ATP released from astrocytes facilitates a recruitment of P2X receptors into excitatory synapses by Ca2+-dependent mechanism. P2X receptors, co-localized with NMDA receptors in the excitatory synapses, can be activated by ATP co-released with glutamate from pre-synaptic terminals and by glia-derived ATP. An activation of P2X receptors in turn leads to down-regulation of postsynaptic NMDA receptors via Ca2+-dependent de-phosphorylation and interaction with PSD-95 multi-protein complex. Genetic deletion of the PSD-95 or P2X4 receptors obliterated ATP-mediated down-regulation of NMDA receptors. Impairment of purinergic modulation of NMDA receptors in the PSD-95 mutants dramatically decreased the threshold of LTP induction and increased the net magnitude of LTP. Our findings show that synergistic action of glia- and neurone-derived ATP can pre-modulate efficacy of excitatory synapses and thereby can have an important role in the glia-neuron communications and brain meta-plasticity.
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31
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Tsuda M. P2 receptors, microglial cytokines and chemokines, and neuropathic pain. J Neurosci Res 2016; 95:1319-1329. [DOI: 10.1002/jnr.23816] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Revised: 05/19/2016] [Accepted: 06/13/2016] [Indexed: 01/12/2023]
Affiliation(s)
- Makoto Tsuda
- Department of Life Innovation, Department of Molecular and System Pharmacology, Graduate School of Pharmaceutical Sciences; Kyushu University; Fukuoka Japan
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32
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Shcherbatko A, Foletti D, Poulsen K, Strop P, Zhu G, Hasa-Moreno A, Melton Witt J, Loo C, Krimm S, Pios A, Yu J, Brown C, Lee JK, Stroud R, Rajpal A, Shelton D. Modulation of P2X3 and P2X2/3 Receptors by Monoclonal Antibodies. J Biol Chem 2016; 291:12254-70. [PMID: 27129281 DOI: 10.1074/jbc.m116.722330] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Indexed: 01/06/2023] Open
Abstract
Purinergic homomeric P2X3 and heteromeric P2X2/3 receptors are ligand-gated cation channels activated by ATP. Both receptors are predominantly expressed in nociceptive sensory neurons, and an increase in extracellular ATP concentration under pathological conditions, such as tissue damage or visceral distension, induces channel opening, membrane depolarization, and initiation of pain signaling. Hence, these receptors are considered important therapeutic targets for pain management, and development of selective antagonists is currently progressing. To advance the search for novel analgesics, we have generated a panel of monoclonal antibodies directed against human P2X3 (hP2X3). We have found that these antibodies produce distinct functional effects, depending on the homomeric or heteromeric composition of the target, its kinetic state, and the duration of antibody exposure. The most potent antibody, 12D4, showed an estimated IC50 of 16 nm on hP2X3 after short term exposure (up to 18 min), binding to the inactivated state of the channel to inhibit activity. By contrast, with the same short term application, 12D4 potentiated the slow inactivating current mediated by the heteromeric hP2X2/3 channel. Extending the duration of exposure to ∼20 h resulted in a profound inhibition of both homomeric hP2X3 and heteromeric hP2X2/3 receptors, an effect mediated by efficient antibody-induced internalization of the channel from the plasma membrane. The therapeutic potential of mAb12D4 was assessed in the formalin, complete Freund's adjuvant, and visceral pain models. The efficacy of 12D4 in the visceral hypersensitivity model indicates that antibodies against P2X3 may have therapeutic potential in visceral pain indications.
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Affiliation(s)
- Anatoly Shcherbatko
- From the Rinat Laboratories, Pfizer Inc., South San Francisco, California 94080,
| | - Davide Foletti
- From the Rinat Laboratories, Pfizer Inc., South San Francisco, California 94080
| | - Kris Poulsen
- From the Rinat Laboratories, Pfizer Inc., South San Francisco, California 94080
| | - Pavel Strop
- From the Rinat Laboratories, Pfizer Inc., South San Francisco, California 94080
| | - Guoyun Zhu
- From the Rinat Laboratories, Pfizer Inc., South San Francisco, California 94080
| | - Adela Hasa-Moreno
- From the Rinat Laboratories, Pfizer Inc., South San Francisco, California 94080
| | - Jody Melton Witt
- From the Rinat Laboratories, Pfizer Inc., South San Francisco, California 94080
| | - Carole Loo
- From the Rinat Laboratories, Pfizer Inc., South San Francisco, California 94080
| | - Stellanie Krimm
- From the Rinat Laboratories, Pfizer Inc., South San Francisco, California 94080
| | - Ariel Pios
- From the Rinat Laboratories, Pfizer Inc., South San Francisco, California 94080
| | - Jessica Yu
- From the Rinat Laboratories, Pfizer Inc., South San Francisco, California 94080
| | - Colleen Brown
- From the Rinat Laboratories, Pfizer Inc., South San Francisco, California 94080
| | - John K Lee
- the Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, Minnesota 55455, and
| | - Robert Stroud
- the Department of Biochemistry and Biophysics, University of California, San Francisco, California 94158
| | - Arvind Rajpal
- From the Rinat Laboratories, Pfizer Inc., South San Francisco, California 94080
| | - David Shelton
- From the Rinat Laboratories, Pfizer Inc., South San Francisco, California 94080
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Habermacher C, Martz A, Calimet N, Lemoine D, Peverini L, Specht A, Cecchini M, Grutter T. Photo-switchable tweezers illuminate pore-opening motions of an ATP-gated P2X ion channel. eLife 2016; 5:e11050. [PMID: 26808983 PMCID: PMC4739762 DOI: 10.7554/elife.11050] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2015] [Accepted: 10/27/2015] [Indexed: 11/13/2022] Open
Abstract
P2X receptors function by opening a transmembrane pore in response to extracellular ATP. Recent crystal structures solved in apo and ATP-bound states revealed molecular motions of the extracellular domain following agonist binding. However, the mechanism of pore opening still remains controversial. Here we use photo-switchable cross-linkers as ‘molecular tweezers’ to monitor a series of inter-residue distances in the transmembrane domain of the P2X2 receptor during activation. These experimentally based structural constraints combined with computational studies provide high-resolution models of the channel in the open and closed states. We show that the extent of the outer pore expansion is significantly reduced compared to the ATP-bound structure. Our data further reveal that the inner and outer ends of adjacent pore-lining helices come closer during opening, likely through a hinge-bending motion. These results provide new insight into the gating mechanism of P2X receptors and establish a versatile strategy applicable to other membrane proteins. DOI:http://dx.doi.org/10.7554/eLife.11050.001 Protein receptors in the cell membrane play an important role transmitting signals from outside to inside the cell. Members of the P2X family of receptors are ion channels that form pores through the membrane. When a molecule of ATP binds to the external region of the receptor, it activates it and causes the receptor to change from a closed to an open shape. Once opened, ions flow through the channel’s pore and trigger a response inside the cell. P2X receptors are found on most animal cells (including nerve cells) and are involved in both normal cellular activity and processes linked to disease, including inflammation and chronic pain. The P2X receptor has three parts or subunits, and each contributes to the channel’s pore. Recent research using a technique called X-ray crystallography has revealed how ATP binding causes shape changes in the external region of the receptor. But these three-dimensional structures did not reveal details of how the subunits move to open or close the channel’s pore. Habermacher et al. have now added light-sensitive linkers onto the P2X receptor in a way that meant that different colors of light could be used to force parts of the receptor to come closer together or move apart. This allowed the pore to be opened and closed in response to changes in light. Habermacher et al. then studied the behavior of these modified receptors within a natural membrane and found that the light stimulated movements were similar to those seen with ATP. When the behavior of the receptor and light-sensitive linkers was studied using computer simulations, it led to new models of the P2X pore in the open and closed state. In these models, the open channel was more tightly packed than in the previous structure and an unexpected hinge-bending movement was seen to accompany the opening of the channel. It is hoped that this new approach will also be useful for probing how other membrane proteins change their shape when activated. DOI:http://dx.doi.org/10.7554/eLife.11050.002
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Affiliation(s)
- Chloé Habermacher
- Université de Strasbourg, Faculté de Pharmacie, Illkirch, France.,Centre National de la Recherche Scientifique, Laboratoire de Conception et Application de Molécules Bioactives, Unité Mixte de Recherche 7199, Équipe de Chimie et Neurobiologie Moléculaire, Illkirch, France
| | - Adeline Martz
- Université de Strasbourg, Faculté de Pharmacie, Illkirch, France.,Centre National de la Recherche Scientifique, Laboratoire de Conception et Application de Molécules Bioactives, Unité Mixte de Recherche 7199, Équipe de Chimie et Neurobiologie Moléculaire, Illkirch, France
| | - Nicolas Calimet
- ISIS, Unité Mixte de Recherche 7006, Laboratoire d'Ingénierie des Fonctions Moléculaires, Strasbourg, France
| | - Damien Lemoine
- Université de Strasbourg, Faculté de Pharmacie, Illkirch, France.,Centre National de la Recherche Scientifique, Laboratoire de Conception et Application de Molécules Bioactives, Unité Mixte de Recherche 7199, Équipe de Chimie et Neurobiologie Moléculaire, Illkirch, France
| | - Laurie Peverini
- Université de Strasbourg, Faculté de Pharmacie, Illkirch, France.,Centre National de la Recherche Scientifique, Laboratoire de Conception et Application de Molécules Bioactives, Unité Mixte de Recherche 7199, Équipe de Chimie et Neurobiologie Moléculaire, Illkirch, France
| | - Alexandre Specht
- Université de Strasbourg, Faculté de Pharmacie, Illkirch, France.,Centre National de la Recherche Scientifique, Laboratoire de Conception et Application de Molécules Bioactives, Unité Mixte de Recherche 7199, Équipe de Chimie et Neurobiologie Moléculaire, Illkirch, France
| | - Marco Cecchini
- ISIS, Unité Mixte de Recherche 7006, Laboratoire d'Ingénierie des Fonctions Moléculaires, Strasbourg, France
| | - Thomas Grutter
- Université de Strasbourg, Faculté de Pharmacie, Illkirch, France.,Centre National de la Recherche Scientifique, Laboratoire de Conception et Application de Molécules Bioactives, Unité Mixte de Recherche 7199, Équipe de Chimie et Neurobiologie Moléculaire, Illkirch, France
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Habermacher C, Dunning K, Chataigneau T, Grutter T. Molecular structure and function of P2X receptors. Neuropharmacology 2015; 104:18-30. [PMID: 26231831 DOI: 10.1016/j.neuropharm.2015.07.032] [Citation(s) in RCA: 79] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Revised: 07/23/2015] [Accepted: 07/26/2015] [Indexed: 12/22/2022]
Abstract
ATP-gated P2X receptors are trimeric ion channels selective to cations. Recent progress in the molecular biophysics of these channels enables a better understanding of their function. In particular, data obtained from biochemical, electrophysiogical and molecular engineering in the light of recent X-ray structures now allow delineation of the principles of ligand binding, channel opening and allosteric modulation. However, although a picture emerges as to how ATP triggers channel opening, there are a number of intriguing questions that remain to be answered, in particular how the pore itself opens in response to ATP and how the intracellular domain, for which structural information is limited, moves during activation. In this review, we provide a summary of functional studies in the context of the post-structure era, aiming to clarify our understanding of the way in which P2X receptors function in response to ATP binding, as well as the mechanism by which allosteric modulators are able to regulate receptor function. This article is part of the Special Issue entitled 'Purines in Neurodegeneration and Neuroregeneration'.
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Affiliation(s)
- Chloé Habermacher
- Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7199, Laboratoire de Conception et Application de Molécules Bioactives, Équipe de Chimie et Neurobiologie Moléculaire, F-67400, Illkirch, France; Université de Strasbourg, Faculté de Pharmacie, F-67400, Illkirch, France
| | - Kate Dunning
- Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7199, Laboratoire de Conception et Application de Molécules Bioactives, Équipe de Chimie et Neurobiologie Moléculaire, F-67400, Illkirch, France; Université de Strasbourg, Faculté de Pharmacie, F-67400, Illkirch, France
| | - Thierry Chataigneau
- Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7199, Laboratoire de Conception et Application de Molécules Bioactives, Équipe de Chimie et Neurobiologie Moléculaire, F-67400, Illkirch, France; Université de Strasbourg, Faculté de Pharmacie, F-67400, Illkirch, France
| | - Thomas Grutter
- Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7199, Laboratoire de Conception et Application de Molécules Bioactives, Équipe de Chimie et Neurobiologie Moléculaire, F-67400, Illkirch, France; Université de Strasbourg, Faculté de Pharmacie, F-67400, Illkirch, France.
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35
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Robinson LE, Shridar M, Smith P, Murrell-Lagnado RD. Plasma membrane cholesterol as a regulator of human and rodent P2X7 receptor activation and sensitization. J Biol Chem 2014; 289:31983-31994. [PMID: 25281740 PMCID: PMC4231676 DOI: 10.1074/jbc.m114.574699] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
P2X7 receptors are nonselective cation channels gated by high extracellular ATP, but with sustained activation, receptor sensitization occurs, whereby the intrinsic pore dilates, making the cell permeable to large organic cations, which eventually leads to cell death. P2X7 receptors associate with cholesterol-rich lipid rafts, but it is unclear how this affects the properties of the receptor channel. Here we show that pore-forming properties of human and rodent P2X7 receptors are sensitive to perturbations of cholesterol levels. Acute depletion of cholesterol with 5 mm methyl-β-cyclodextrin (MCD) caused a substantial increase in the rate of agonist-evoked pore formation, as measured by the uptake of ethidium dye, whereas cholesterol loading inhibited this process. Patch clamp analysis of P2X7 receptor currents carried by Na+ and N-methyl-d-glucamine (NMDG+) showed enhanced activation and current facilitation following cholesterol depletion. This contrasts with the inhibitory effect of methyl-β-cyclodextrin reported for other P2X subtypes. Mutational analysis suggests the involvement of an N-terminal region and a proximal C-terminal region that comprises multiple cholesterol recognition amino acid consensus (CRAC) motifs, in the cholesterol sensitivity of channel gating. These results reveal cholesterol as a negative regulator of P2X7 receptor pore formation, protecting cells from P2X7-mediated cell death.
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Affiliation(s)
- Lucy E Robinson
- Department of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1PD, United Kingdom
| | - Mitesh Shridar
- Department of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1PD, United Kingdom
| | - Philip Smith
- Department of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1PD, United Kingdom
| | - Ruth D Murrell-Lagnado
- Department of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1PD, United Kingdom.
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36
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Limapichat W, Dougherty DA, Lester HA. Subtype-specific mechanisms for functional interaction between α6β4* nicotinic acetylcholine receptors and P2X receptors. Mol Pharmacol 2014; 86:263-74. [PMID: 24966348 PMCID: PMC4152909 DOI: 10.1124/mol.114.093179] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2014] [Accepted: 06/24/2014] [Indexed: 11/22/2022] Open
Abstract
P2X receptors and nicotinic acetylcholine receptors (nAChRs) display functional and physical interactions in many cell types and heterologous expression systems, but interactions between α6β4-containing (α6β4*) nAChRs and P2X2 receptors and/or P2X3 receptors have not been fully characterized. We measured several types of crosstalk in oocytes coexpressing α6β4 nAChRs and P2X2, P2X3, or P2X2/3 receptors. A novel form of crosstalk occurs between α6β4 nAChRs and P2X2 receptors. P2X2 receptors were forced into a prolonged desensitized state upon activation by ATP through a mechanism that does not depend on the intracellular C terminus of the P2X2 receptors. Coexpression of α6β4 nAChRs with P2X3 receptors shifts the ATP dose-response relation to the right, even in the absence of acetylcholine (ACh). Moreover, currents become nonadditive when ACh and ATP are coapplied, as previously reported for other Cys-loop receptors interacting with P2X receptors, and this crosstalk is dependent on the presence of the P2X3 C-terminal domain. P2X2 receptors also functionally interact with α6β4β3 but through a different mechanism from α6β4. The interaction with P2X3 receptors is less pronounced for the α6β4β3 nAChR than the α6β4 nAChR. We also measured a functional interaction between the α6β4 nAChRs and the heteromeric P2X2/3 receptor. Experiments with the nAChR channel blocker mecamylamine on P2X2-α6β4 oocytes point to the loss of P2X2 channel activity during the crosstalk, whereas the ion channel pores of the P2X receptors were fully functional and unaltered by the receptor interaction for P2X2-α6β4β3, P2X2/3-α6β4, and P2X2/3-α6β4β3. These results may be relevant to dorsal root ganglion cells and to other neurons that coexpress these receptor subunits.
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Affiliation(s)
- Walrati Limapichat
- Divisions of Chemistry and Chemical Engineering (W.L., D.A.D.) and Biology and Biological Engineering (H.A.L.), California Institute of Technology, Pasadena, California
| | - Dennis A Dougherty
- Divisions of Chemistry and Chemical Engineering (W.L., D.A.D.) and Biology and Biological Engineering (H.A.L.), California Institute of Technology, Pasadena, California
| | - Henry A Lester
- Divisions of Chemistry and Chemical Engineering (W.L., D.A.D.) and Biology and Biological Engineering (H.A.L.), California Institute of Technology, Pasadena, California
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37
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Fiebich BL, Akter S, Akundi RS. The two-hit hypothesis for neuroinflammation: role of exogenous ATP in modulating inflammation in the brain. Front Cell Neurosci 2014; 8:260. [PMID: 25225473 PMCID: PMC4150257 DOI: 10.3389/fncel.2014.00260] [Citation(s) in RCA: 86] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Accepted: 08/14/2014] [Indexed: 11/13/2022] Open
Abstract
Brain inflammation is a common occurrence following responses to varied insults such as bacterial infections, stroke, traumatic brain injury and neurodegenerative disorders. A common mediator for these varied inflammatory responses is prostaglandin E2 (PGE2), produced by the enzymatic activity of cyclooxygenases (COX) 1 and 2. Previous attempts to reduce neuronal inflammation through COX inhibition, by use of nonsteroidal anti-inflammatory drugs (NSAIDs), have met with limited success. We are proposing the two-hit model for neuronal injury—an initial localized inflammation mediated by PGE2 (first hit) and the simultaneous release of adenosine triphosphate (ATP) by injured cells (second hit), which significantly enhances the inflammatory response through increased synthesis of PGE2. Several evidences on the role of exogenous ATP in inflammation have been reported, including contrary instances where extracellular ATP reduces inflammatory events. In this review, we will examine the current literature on the role of P2 receptors, to which ATP binds, in modulating inflammatory reactions during neurodegeneration. Targeting the P2 receptors, therefore, provides a therapeutic alternative to reduce inflammation in the brain. P2 receptor-based anti-inflammatory drugs (PBAIDs) will retain the activities of essential COX enzymes, yet will significantly reduce neuroinflammation by decreasing the enhanced production of PGE2 by extracellular ATP.
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Affiliation(s)
- Bernd L Fiebich
- Department of Psychiatry and Psychotherapy, Neurochemistry Research Laboratory, University of Freiburg Medical School Freiburg, Germany
| | - Shamima Akter
- Neuroinflammation Research Laboratory, Faculty of Life Sciences and Biotechnology, South Asian University New Delhi, Delhi, India
| | - Ravi Shankar Akundi
- Neuroinflammation Research Laboratory, Faculty of Life Sciences and Biotechnology, South Asian University New Delhi, Delhi, India
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38
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Macrophage P2X7 receptor function is reduced during schistosomiasis: putative role of TGF- β1. Mediators Inflamm 2014; 2014:134974. [PMID: 25276050 PMCID: PMC4158569 DOI: 10.1155/2014/134974] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2014] [Revised: 07/14/2014] [Accepted: 08/04/2014] [Indexed: 12/05/2022] Open
Abstract
Schistosomiasis is a chronic inflammatory disease whose macrophages are involved in immunopathology modulation. Although P2X7 receptor signaling plays an important role in inflammatory responses mediated by macrophages, no reports have examined the role of P2X7 receptors in macrophage function during schistosomiasis. Thus, we evaluated P2X7 receptor function in peritoneal macrophages during schistosomiasis using an ATP-induced permeabilization assay and measurements of the intracellular Ca2+ concentration. ATP treatment induced significantly less permeabilization in macrophages from S. mansoni-infected mice than in control cells from uninfected animals. Furthermore, P2X7-mediated increases in intracellular Ca2+ levels were also reduced in macrophages from infected mice. TGF-β1 levels were increased in the peritoneal cavity of infected animals, and pretreatment of control macrophages with TGF-β1 reduced ATP-induced permeabilization, mimicking the effect of S. mansoni infection. Western blot and qRT-PCR data showed no difference in P2X7 protein and mRNA between uninfected, infected, and TGF-β1-treated groups. However, immunofluorescence analysis revealed reduced cell surface localization of P2X7 receptors in macrophages from infected and TGF-β1-treated mice compared to controls. Therefore, our data suggest that schistosomiasis reduces peritoneal macrophage P2X7 receptor signaling. This effect is likely due to the fact that infected mice have increased levels of TGF-β1, which reduces P2X7 receptor cell surface expression.
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39
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Burnstock G, Nistri A, Khakh BS, Giniatullin R. ATP-gated P2X receptors in health and disease. Front Cell Neurosci 2014; 8:204. [PMID: 25104924 PMCID: PMC4109572 DOI: 10.3389/fncel.2014.00204] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2014] [Accepted: 07/07/2014] [Indexed: 12/18/2022] Open
Affiliation(s)
- Geoffrey Burnstock
- Division of Biosciences, Autonomic Neuroscience Centre, University College Medical School London, UK ; Department of Pharmacology and Therapeutics, The University of Melbourne Parkville, VIC, Australia
| | - Andrea Nistri
- Neuroscience Department, International School for Advanced Studies (SISSA) Trieste, Italy
| | - Baljit S Khakh
- Department of Physiology, David Geffen School of Medicine, University of California, Los Angeles Los Angeles, CA, USA
| | - Rashid Giniatullin
- Department Neurobiology, A. I. Virtanen Institute, University of Eastern Finland Kuopio, Finland ; Laboratory of Neurobiology, Department of Physiology, Kazan Federal University Kazan, Russia
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40
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Xu J, Chai H, Ehinger K, Egan TM, Srinivasan R, Frick M, Khakh BS. Imaging P2X4 receptor subcellular distribution, trafficking, and regulation using P2X4-pHluorin. ACTA ACUST UNITED AC 2014; 144:81-104. [PMID: 24935743 PMCID: PMC4076521 DOI: 10.1085/jgp.201411169] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
A P2X4 receptor labeled with the pH-sensitive GFP superecliptic pHluorin represents a useful probe to investigate P2X4 receptor distribution, trafficking, and up-regulation. P2X4 receptors are adenosine triphosphate (ATP)-gated cation channels present on the plasma membrane (PM) and also within intracellular compartments such as vesicles, vacuoles, lamellar bodies (LBs), and lysosomes. P2X4 receptors in microglia are up-regulated in epilepsy and in neuropathic pain; that is to say, their total and/or PM expression levels increase. However, the mechanisms underlying up-regulation of microglial P2X4 receptors remain unclear, in part because it has not been possible to image P2X4 receptor distribution within, or trafficking between, cellular compartments. Here, we report the generation of pH-sensitive fluorescently tagged P2X4 receptors that permit evaluations of cell surface and total receptor pools. Capitalizing on information gained from zebrafish P2X4.1 crystal structures, we designed a series of mouse P2X4 constructs in which a pH-sensitive green fluorescent protein, superecliptic pHluorin (pHluorin), was inserted into nonconserved regions located within flexible loops of the P2X4 receptor extracellular domain. One of these constructs, in which pHluorin was inserted after lysine 122 (P2X4-pHluorin123), functioned like wild-type P2X4 in terms of its peak ATP-evoked responses, macroscopic kinetics, calcium flux, current–voltage relationship, and sensitivity to ATP. P2X4-pHluorin123 also showed pH-dependent fluorescence changes, and was robustly expressed on the membrane and within intracellular compartments. P2X4-pHluorin123 identified cell surface and intracellular fractions of receptors in HEK-293 cells, hippocampal neurons, C8-B4 microglia, and alveolar type II (ATII) cells. Furthermore, it showed that the subcellular fractions of P2X4-pHluorin123 receptors were cell and compartment specific, for example, being larger in hippocampal neuron somata than in C8-B4 cell somata, and larger in C8-B4 microglial processes than in their somata. In ATII cells, P2X4-pHluorin123 showed that P2X4 receptors were secreted onto the PM when LBs undergo exocytosis. Finally, the use of P2X4-pHluorin123 showed that the modulator ivermectin did not increase the PM fraction of P2X4 receptors and acted allosterically to potentiate P2X4 receptor responses. Collectively, our data suggest that P2X4-pHluorin123 represents a useful optical probe to quantitatively explore P2X4 receptor distribution, trafficking, and up-regulation.
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Affiliation(s)
- Ji Xu
- Department of Physiology and Department of Neurobiology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095
| | - Hua Chai
- Department of Physiology and Department of Neurobiology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095
| | | | - Terrance M Egan
- Department of Pharmacological and Physiological Science and The Center for Excellence in Neuroscience, Saint Louis University School of Medicine, St. Louis, MO 63130 Department of Pharmacological and Physiological Science and The Center for Excellence in Neuroscience, Saint Louis University School of Medicine, St. Louis, MO 63130
| | - Rahul Srinivasan
- Department of Physiology and Department of Neurobiology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095
| | - Manfred Frick
- Institute of General Physiology, University of Ulm, 89081 Ulm, Germany
| | - Baljit S Khakh
- Department of Physiology and Department of Neurobiology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095Department of Physiology and Department of Neurobiology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095
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41
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Kellenberger S, Grutter T. Architectural and functional similarities between trimeric ATP-gated P2X receptors and acid-sensing ion channels. J Mol Biol 2014; 427:54-66. [PMID: 24937752 DOI: 10.1016/j.jmb.2014.06.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2014] [Revised: 06/05/2014] [Accepted: 06/09/2014] [Indexed: 12/17/2022]
Abstract
ATP-gated P2X receptors and acid-sensing ion channels are two distinct ligand-gated ion channels that assemble into trimers. They are involved in many important physiological functions such as pain sensation and are recognized as important therapeutic targets. They have unrelated primary structures and respond to different ligands (ATP and protons) and are thus considered as two different ion channels. As a consequence, comparisons of the biophysical properties and underlying mechanisms have only been rarely made between these two channels. However, the recent determination of their molecular structures by X-ray crystallography has revealed unexpected parallels in the architecture of the two pores, providing a basis for possible functional analogies. In this review, we analyze the structural and functional similarities that are shared by these trimeric ion channels, and we outline key unanswered questions that, if addressed experimentally, may help us to elucidate how two unrelated ion channels have adopted a similar fold of the pore.
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Affiliation(s)
- Stephan Kellenberger
- Département de Pharmacologie et de Toxicologie, Université de Lausanne, Rue du Bugnon 27, CH-1005 Lausanne, Switzerland.
| | - Thomas Grutter
- Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7199, Laboratoire de Conception et Application de Molécules Bioactives, Équipe de Chimie et Neurobiologie Moléculaire, F-67400 Illkirch, France; Université de Strasbourg, Faculté de Pharmacie, F-67400 Illkirch, France.
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