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Nardin C, Mammano F. Measurement of Ca 2+ Uptake Through Connexin Hemichannels. Methods Mol Biol 2024; 2801:97-109. [PMID: 38578416 DOI: 10.1007/978-1-0716-3842-2_8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/06/2024]
Abstract
Increasing evidence points to deregulated flux of ionized calcium (Ca2+) mediated by hyperactive mutant connexin (Cx) hemichannels (HCs) as a common gain-of-function etiopathogenetic mechanism for several diseases, ranging from skin disorders to nervous system defects. Furthermore, the opening of nonmutated Cx HCs is associated with an impressive list of widespread diseases including, but not limited to, ischemia/stroke, Alzheimer's disease, and epilepsy. HC inhibitors are attracting a growing attention due to their therapeutic potential for numerous pathologies. This chapter describes a quantitative method to measure Ca2+ uptake though HCs expressed in cultured cells. The assay we developed can be used to probe HC activity as wells as to test HC inhibitors. Furthermore, with minor changes it can be easily adapted to high-throughput high-content platforms and/or primary cells and microtissues.
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Affiliation(s)
- Chiara Nardin
- Institute of Biochemistry and Cell Biology, Italian National Research Council, Rome, Italy
- , Genoa, Italy
| | - Fabio Mammano
- Institute of Biochemistry and Cell Biology, Italian National Research Council, Rome, Italy.
- Department of Physics and Astronomy "G. Galilei", University of Padova, Padova, Italy.
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2
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Ek-Vitorin JF, Silva-Mendoza D, Pontifex TK, Burt JM. Channel Behavior and Voltage Gating of a Cx43 Mutant Simulating Preconditioning. Bioelectricity 2023; 5:181-187. [PMID: 37746309 PMCID: PMC10516231 DOI: 10.1089/bioe.2023.0024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/26/2023] Open
Abstract
Background Ischemic preconditioning induces lateralization and dephosphorylation of Connexin 43 (Cx43). However, the Cx43 protein that remains at intercalated disks may be phosphorylated by casein kinase 1 (CK1) and protein kinase C (PKC), and both kinases provide cardioprotection from further ischemic injury. Here we explore the channel characteristics of a Cx43 mutant mimicking preconditioning by CK1 and PKC phosphorylation. Materials and Methods Whole-cell patch-clamp recordings were performed in cells expressing the mutant Cx43pc (S325,328,330,368D, S365A-Cx43), and the connexin electrical behavior was analyzed at the single channel and macroscopic level. Results Cx43pc hemichannels opened readily, whereas gap junctions channels displayed amplitudes between the wild-type and CK1 phosphorylated forms, and weaker voltage gating than either counterpart. Conclusions Ischemic preconditioning and the ensuing phosphorylation of Cx43 by PKC may render junctional channels insensitive to transjunctional voltages, allowing the preservation of intercellular communication in ischemic conditions.
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Affiliation(s)
| | | | - Tasha K. Pontifex
- Department of Physiology, University of Arizona, Tucson, Arizona, USA
| | - Janis M. Burt
- Department of Physiology, University of Arizona, Tucson, Arizona, USA
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3
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Ek-Vitorin JF, Jiang JX. The Role of Gap Junctions Dysfunction in the Development of Cataracts: From Loss of Cell-to-Cell Transfer to Blurred Vision-Review. Bioelectricity 2023; 5:164-172. [PMID: 37746311 PMCID: PMC10516237 DOI: 10.1089/bioe.2023.0025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/26/2023] Open
Abstract
Mutations of lens connexins are linked to congenital cataracts. However, the role of connexin mutations in the development of age-related lens opacification remains largely unknown. Here, we present a focused review of the literature on lens organization and factors associated with cataract development. Several lines of evidence indicate that disturbances of the lens circulation by dysfunctional connexin channels, and/or accumulation of protein damage due to oxidative stress, are key factors in cataract development. Phosphorylation by protein kinase A improves the permeability of connexins channels to small molecules and mitigates the lens clouding induced by oxidative stress. We conclude (1) that connexin channels are central to the lens circulation and (2) that their permeability to antioxidant molecules contributes to the maintenance of lens transparency.
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Affiliation(s)
| | - Jean X. Jiang
- Department of Biochemistry and Structural Biology, University of Texas Health Science Center, San Antonio, Texas, USA
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4
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Peres C, Sellitto C, Nardin C, Putti S, Orsini T, Di Pietro C, Marazziti D, Vitiello A, Calistri A, Rigamonti M, Scavizzi F, Raspa M, Zonta F, Yang G, White TW, Mammano F. Antibody gene transfer treatment drastically improves epidermal pathology in a keratitis ichthyosis deafness syndrome model using male mice. EBioMedicine 2023; 89:104453. [PMID: 36736132 PMCID: PMC9926223 DOI: 10.1016/j.ebiom.2023.104453] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Revised: 12/30/2022] [Accepted: 01/11/2023] [Indexed: 02/04/2023] Open
Abstract
BACKGROUND Keratitis ichthyosis deafness (KID) syndrome is a rare disorder caused by hemichannel (HC) activating gain-of-function mutations in the GJB2 gene encoding connexin (Cx) 26, for which there is no cure, or current treatments based upon the mechanism of disease causation. METHODS We applied Adeno Associated Virus (AAV) mediated mAb gene transfer (AAVmAb) to treat the epidermal features of KID syndrome with a well-characterized HC blocking antibody using male mice of a murine model that replicates the skin pathology of the human disease. FINDINGS We demonstrate that in vivo AAVmAb treatment significantly reduced the size and thickness of KID lesions, in addition to blocking activity of mutant HCs in the epidermis in vivo. We also show that AAVmAb treatment eliminated abnormal keratinocyte proliferation and enlarged cell size, decreased apoptosis, and restored the normal distribution of keratin expression. INTERPRETATION Our findings reinforce the critical role played by increased HC activity in the skin pathology associated with KID syndrome. They also underscore the clinical potential of anti-HC mAbs coupled with genetic based delivery systems for treating the underlying mechanistic basis of this disorder. Inhibition of HC activity is an ideal therapeutic target in KID syndrome, and the genetic delivery of mAbs targeted against mutant HCs could form the basis of new therapeutic interventions to treat this incurable disease. FUNDING Fondazione Telethon grant GGP19148 and University of Padova grant Prot. BIRD187130 to FM; Foundation for Ichthyosis and Related Skin Types (FIRST) and National Institutes of Health grant EY 026911 to TWW.
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Affiliation(s)
- Chiara Peres
- Institute of Biochemistry and Cell Biology, Italian National Research Council, 00015 Monterotondo, Rome, Italy
| | - Caterina Sellitto
- Department of Physiology and Biophysics, Stony Brook University, T5-147, Basic Science Tower; Stony Brook, NY, 11794-8661, USA
| | - Chiara Nardin
- Institute of Biochemistry and Cell Biology, Italian National Research Council, 00015 Monterotondo, Rome, Italy
| | - Sabrina Putti
- Institute of Biochemistry and Cell Biology, Italian National Research Council, 00015 Monterotondo, Rome, Italy
| | - Tiziana Orsini
- Institute of Biochemistry and Cell Biology, Italian National Research Council, 00015 Monterotondo, Rome, Italy
| | - Chiara Di Pietro
- Institute of Biochemistry and Cell Biology, Italian National Research Council, 00015 Monterotondo, Rome, Italy
| | - Daniela Marazziti
- Institute of Biochemistry and Cell Biology, Italian National Research Council, 00015 Monterotondo, Rome, Italy
| | - Adriana Vitiello
- Department of Molecular Medicine, University of Padova, 35121, Padova, Italy
| | - Arianna Calistri
- Department of Molecular Medicine, University of Padova, 35121, Padova, Italy
| | | | - Ferdinando Scavizzi
- Institute of Biochemistry and Cell Biology, Italian National Research Council, 00015 Monterotondo, Rome, Italy
| | - Marcello Raspa
- Institute of Biochemistry and Cell Biology, Italian National Research Council, 00015 Monterotondo, Rome, Italy
| | - Francesco Zonta
- Shanghai Institute for Advanced Immunochemical Studies, ShanghaiTech University, Shanghai, 201210, China
| | - Guang Yang
- Shanghai Institute for Advanced Immunochemical Studies, ShanghaiTech University, Shanghai, 201210, China
| | - Thomas W White
- Department of Physiology and Biophysics, Stony Brook University, T5-147, Basic Science Tower; Stony Brook, NY, 11794-8661, USA.
| | - Fabio Mammano
- Institute of Biochemistry and Cell Biology, Italian National Research Council, 00015 Monterotondo, Rome, Italy; Department of Physics and Astronomy "G. Galilei", University of Padova, 35131, Padova, Italy.
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5
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Vega JL, Gutiérrez C, Rojas M, Güiza J, Sáez JC. Contribution of large-pore channels to inflammation induced by microorganisms. Front Cell Dev Biol 2023; 10:1094362. [PMID: 36699007 PMCID: PMC9868820 DOI: 10.3389/fcell.2022.1094362] [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: 11/10/2022] [Accepted: 12/22/2022] [Indexed: 01/12/2023] Open
Abstract
Plasma membrane ionic channels selectively permeate potassium, sodium, calcium, and chloride ions. However, large-pore channels are permeable to ions and small molecules such as ATP and glutamate, among others. Large-pore channels are structures formed by several protein families with little or no evolutionary linkages including connexins (Cxs), pannexins (Panxs), innexin (Inxs), unnexins (Unxs), calcium homeostasis modulator (CALHMs), and Leucine-rich repeat-containing 8 (LRRC8) proteins. Large-pore channels are key players in inflammatory cell response, guiding the activation of inflammasomes, the release of pro-inflammatory cytokines such as interleukin-1 beta (IL-1ß), and the release of adenosine-5'-triphosphate (ATP), which is considered a danger signal. This review summarizes our current understanding of large-pore channels and their contribution to inflammation induced by microorganisms, virulence factors or their toxins.
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Affiliation(s)
- José L. Vega
- Laboratory of Gap Junctions Proteins and Parasitic Diseases (GaPaL), Instituto Antofagasta, Universidad de Antofagasta, Antofagasta, Chile,Centro de Investigación en Inmunología y Biotecnología Biomédica de Antofagasta (CIIBBA), Universidad de Antofagasta, Antofagasta, Chile,Centro de Fisiología y Medicina de Altura (FIMEDALT), Universidad de Antofagasta, Antofagasta, Chile,*Correspondence: José L. Vega,
| | - Camila Gutiérrez
- Laboratory of Gap Junctions Proteins and Parasitic Diseases (GaPaL), Instituto Antofagasta, Universidad de Antofagasta, Antofagasta, Chile
| | - Mauro Rojas
- Laboratory of Gap Junctions Proteins and Parasitic Diseases (GaPaL), Instituto Antofagasta, Universidad de Antofagasta, Antofagasta, Chile
| | - Juan Güiza
- Laboratory of Gap Junctions Proteins and Parasitic Diseases (GaPaL), Instituto Antofagasta, Universidad de Antofagasta, Antofagasta, Chile
| | - Juan C. Sáez
- Centro Interdisciplinario de Neurociencias de Valparaíso (CINV), Instituto de Neurociencias, Universidad de Valparaíso, Valparaíso, Chile
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6
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Ek-Vitorin JF, Shahidullah M, Lopez Rosales JE, Delamere NA. Patch clamp studies on TRPV4-dependent hemichannel activation in lens epithelium. Front Pharmacol 2023; 14:1101498. [PMID: 36909173 PMCID: PMC9998544 DOI: 10.3389/fphar.2023.1101498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Accepted: 02/06/2023] [Indexed: 02/26/2023] Open
Abstract
ATP release from the lens via hemichannels has been explained as a response to TRPV4 activation when the lens is subjected to osmotic swelling. To explore the apparent linkage between TRPV4 activation and connexin hemichannel opening we performed patch-clamp recordings on cultured mouse lens epithelial cells exposed to the TRPV4 agonist GSK1016790A (GSK) in the presence or absence of the TRPV4 antagonist HC067047 (HC). GSK was found to cause a fast, variable and generally large non-selective increase of whole cell membrane conductance evident as a larger membrane current (Im) over a wide voltage range. The response was prevented by HC. The GSK-induced Im increase was proportionally larger at negative voltages and coincided with fast depolarization and the simultaneous disappearance of an outward current, likely a K+ current. The presence of this outward current in control conditions appeared to be a reliable predictor of a cell's response to GSK treatment. In some studies, recordings were obtained from single cells by combining cell-attached and whole-cell patch clamp configurations. This approach revealed events with a channel conductance 180-270 pS following GSK application through the patch pipette on the cell-attached side. The findings are consistent with TRPV4-dependent opening of Cx43 hemichannels.
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Affiliation(s)
- Jose F Ek-Vitorin
- Department of Physiology, University of Arizona, Tucson, AZ, United States
| | - Mohammad Shahidullah
- Department of Physiology, University of Arizona, Tucson, AZ, United States.,Department of Ophthalmology and Vision Science, University of Arizona, Tucson, AZ, United States
| | | | - Nicholas A Delamere
- Department of Physiology, University of Arizona, Tucson, AZ, United States.,Department of Ophthalmology and Vision Science, University of Arizona, Tucson, AZ, United States
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7
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A Quantitative Assay for Ca2+ Uptake through Normal and Pathological Hemichannels. Int J Mol Sci 2022; 23:ijms23137337. [PMID: 35806342 PMCID: PMC9266989 DOI: 10.3390/ijms23137337] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Revised: 06/26/2022] [Accepted: 06/28/2022] [Indexed: 12/25/2022] Open
Abstract
Connexin (Cx) hemichannels (HCs) are large pore hexameric structures that allow the exchange of ions, metabolites and a variety of other molecules between the cell cytoplasm and extracellular milieu. HC inhibitors are attracting growing interest as drug candidates because deregulated fluxes through HCs have been implicated in a plethora of genetic conditions and other diseases. HC activity has been mainly investigated by electrophysiological methods and/or using HC-permeable dye uptake measurements. Here, we present an all-optical assay based on fluorometric measurements of ionized calcium (Ca2+) uptake with a Ca2+-selective genetically encoded indicator (GCaMP6s) that permits the optical tracking of cytosolic Ca2+ concentration ([Ca2+]cyt) changes with high sensitivity. We exemplify use of the assay in stable pools of HaCaT cells overexpressing human Cx26, Cx46, or the pathological mutant Cx26G45E, under control of a tetracycline (Tet) responsive element (TRE) promoter (Tet-on). We demonstrate the usefulness of the assay for the characterization of new monoclonal antibodies (mAbs) targeting the extracellular domain of the HCs. Although we developed the assay on a spinning disk confocal fluorescence microscope, the same methodology can be extended seamlessly to high-throughput high-content platforms to screen other kinds of inhibitors and/or to probe HCs expressed in primary cells and microtissues.
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8
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Delamere NA, Shahidullah M. Ion Transport Regulation by TRPV4 and TRPV1 in Lens and Ciliary Epithelium. Front Physiol 2022; 12:834916. [PMID: 35173627 PMCID: PMC8841554 DOI: 10.3389/fphys.2021.834916] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Accepted: 12/27/2021] [Indexed: 02/02/2023] Open
Abstract
Aside from a monolayer of epithelium at the anterior surface, the lens is formed by tightly compressed multilayers of fiber cells, most of which are highly differentiated and have a limited capacity for ion transport. Only the anterior monolayer of epithelial cells has high Na, K-ATPase activity. Because the cells are extensively coupled, the lens resembles a syncytium and sodium-potassium homeostasis of the entire structure is largely dependent on ion transport by the epithelium. Here we describe recent studies that suggest TRPV4 and TRPV1 ion channels activate signaling pathways that play an important role in matching epithelial ion transport activity with needs of the lens cell mass. A TRPV4 feedback loop senses swelling in the fiber mass and increases Na, K-ATPase activity to compensate. TRPV4 channel activation in the epithelium triggers opening of connexin hemichannels, allowing the release of ATP that stimulates purinergic receptors in the epithelium and results in the activation of Src family tyrosine kinases (SFKs) and SFK-dependent increase of Na, K-ATPase activity. A separate TRPV1 feedback loop senses shrinkage in the fiber mass and increases NKCC1 activity to compensate. TRPV1 activation causes calcium-dependent activation of a signaling cascade in the lens epithelium that involves PI3 kinase, ERK, Akt and WNK. TRPV4 and TRPV1 channels are also evident in the ciliary body where Na, K-ATPase is localized on one side of a bilayer in which two different cell types, non-pigmented and pigmented ciliary epithelium, function in a coordinated manner to secrete aqueous humor. TRPV4 and TRPV1 may have a role in maintenance of cell volume homeostasis as ions and water move through the bilayer.
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Shahidullah M, Mandal A, Mathias RT, Gao J, Križaj D, Redmon S, Delamere NA. TRPV1 activation stimulates NKCC1 and increases hydrostatic pressure in the mouse lens. Am J Physiol Cell Physiol 2020; 318:C969-C980. [PMID: 32293931 PMCID: PMC7294325 DOI: 10.1152/ajpcell.00391.2019] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
The porcine lens response to a hyperosmotic stimulus involves an increase in the activity of an ion cotransporter sodium-potassium/two-chloride cotransporter 1 (NKCC1). Recent studies with agonists and antagonists pointed to a mechanism that appears to depend on activation of transient receptor potential vanilloid 1 (TRPV1) ion channels. Here, we compare responses in lenses and cultured lens epithelium obtained from TRPV1-/- and wild type (WT) mice. Hydrostatic pressure (HP) in lens surface cells was determined using a manometer-coupled microelectrode approach. The TRPV1 agonist capsaicin (100 nM) caused a transient HP increase in WT lenses that peaked after ∼30 min and then returned toward baseline. Capsaicin did not cause a detectable change of HP in TRPV1-/- lenses. The NKCC inhibitor bumetanide prevented the HP response to capsaicin in WT lenses. Potassium transport was examined by measuring Rb+ uptake. Capsaicin increased Rb+ uptake in cultured WT lens epithelial cells but not in TRPV1-/- cells. Bumetanide, A889425, and the Akt inhibitor Akti prevented the Rb+ uptake response to capsaicin. The bumetanide-sensitive (NKCC-dependent) component of Rb+ uptake more than doubled in response to capsaicin. Capsaicin also elicited rapid (<2 min) NKCC1 phosphorylation in WT but not TRPV1-/- cells. HP recovery was shown to be absent in TRPV1-/- lenses exposed to hyperosmotic solution. Bumetanide and Akti prevented HP recovery in WT lenses exposed to hyperosmotic solution. Taken together, responses to capsaicin and hyperosmotic solution point to a functional role for TRPV1 channels in mouse lens. Lack of NKCC1 phosphorylation and Rb+ uptake responses in TRPV1-/- mouse epithelium reinforces the notion that a hyperosmotic challenge causes TRPV1-dependent NKCC1 activation. The results are consistent with a role for the TRPV1-activated signaling pathway leading to NKCC1 stimulation in lens osmotic homeostasis.
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Affiliation(s)
- Mohammad Shahidullah
- 1Department of Physiology, University of Arizona, Tucson, Arizona,2Department of Ophthalmology and Vision Science, University of Arizona, Tucson, Arizona
| | - Amritlal Mandal
- 1Department of Physiology, University of Arizona, Tucson, Arizona
| | - Richard T. Mathias
- 3Department of Physiology and Biophysics, Stony Brook University, Stony Brook, New York
| | - Junyuan Gao
- 3Department of Physiology and Biophysics, Stony Brook University, Stony Brook, New York
| | - David Križaj
- 4Department of Ophthalmology and Vision Science, University of Utah School of Medicine, Salt Lake City, Utah
| | - Sarah Redmon
- 4Department of Ophthalmology and Vision Science, University of Utah School of Medicine, Salt Lake City, Utah
| | - Nicholas A. Delamere
- 1Department of Physiology, University of Arizona, Tucson, Arizona,2Department of Ophthalmology and Vision Science, University of Arizona, Tucson, Arizona
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10
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Mandal A, Shahidullah M, Delamere NA. TRPV1-dependent ERK1/2 activation in porcine lens epithelium. Exp Eye Res 2018; 172:128-136. [PMID: 29654770 DOI: 10.1016/j.exer.2018.04.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2018] [Revised: 03/21/2018] [Accepted: 04/10/2018] [Indexed: 01/07/2023]
Abstract
Recently we determined that the Transient Receptor Potential Vanilloid 4 ion channel (TRPV4) has a crucial signaling role in a pathway that regulates various aspects of lens epithelium function. Here, we report on a different TRPV channel, TRPV1, in porcine lens. The presence of TRPV1 in the lens was evident from RT-PCR studies and Western blot analysis of MAPK signaling pathway activation caused by the TRPV1 agonist capsaicin. TRPV1 mRNA was detected in the epithelium of porcine as well as human lens. Transient ERK1/2 and p38 MAPK phosphorylation was detected within 1 min in the epithelium isolated from intact porcine lenses exposed to capsaicin (100 nM), a selective TRPV1 agonist, and the response was significantly inhibited by A889245 (1.0 μM), a TRPV1 antagonist. A similar ERK 1/2 and p38 response in the epithelium, also inhibitable by A889245, was evident in lenses treated with hyperosmotic solution (350 vs 300 mOsm). Lenses pre-treated with either the cytosolic Ca2+ chelator BAPTA-AM or the PKC inhibitor sotrastaurin (1.0 μM) had a diminished ERK1/2 activation response to capsaicin and hyperosmotic solution. Taken together the findings support the notion that TRPV1 functions as a plasma membrane ion channel that, when activated, permits the entry of extracellular calcium into the lens epithelium, leading to activation of PKC, ERK1/2 and p38 MAPK. It is significant that the findings confirm earlier proposals that hyperosmotic stress is linked to TRPV1 channel activation in the mouse lens. Further studies are ongoing to determine what functional changes are triggered by the TRPV1-linked signaling pathways and how they might relate to lens volume homeostasis.
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Affiliation(s)
- Amritlal Mandal
- Department of Physiology, University of Arizona, Tucson, AZ 85724, USA
| | - Mohammad Shahidullah
- Department of Physiology, University of Arizona, Tucson, AZ 85724, USA; Department of Ophthalmology & Vision Science, University of Arizona, Tucson, AZ 85724, USA.
| | - Nicholas A Delamere
- Department of Physiology, University of Arizona, Tucson, AZ 85724, USA; Department of Ophthalmology & Vision Science, University of Arizona, Tucson, AZ 85724, USA
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11
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Cui X, Zhou Z, Zhu K, Feng R, Han J, Li M, Wang S, Li J, Zhang J, Jiang Q, Zhang W, Mu H, Liu Y, Hu Y. A Novel Cx50 Insert Mutation from a Chinese Congenital Cataract Family Impairs Its Cellular Membrane Localization and Function. DNA Cell Biol 2018; 37:449-456. [PMID: 29489419 DOI: 10.1089/dna.2017.4051] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Mutations in GJA8 are associated with hereditary autosomal dominant and recessive cataract formation. In this study, a novel insert mutation in GJA8 was identified in a Chinese congenital cataract family and cosegregated with the disease in this pedigree. This insert mutation introduces five additional amino acid residues YAVHY after histidine at the 95 site (p.H95_A96insYAVHY) within the second transmembrane (TM2) domain of Cx50 protein (Cx50-insert). Ectopic expression of Cx50-insert protein impairs the hemichannel functions and gap junction activity compared to wild-type Cx50 protein in human lens epithelial cells. Cx50-insert proteins were mislocated from cytoplasmic membrane to endoplasmic reticulum and lysosome. In mouse lens tissue, our results showed that Cx50 predominant expresses in epithelial cells and fiber cells at the transition zone of lens hinting its roles in lens differentiation. Taken together, these data suggest that the novel insert mutation in the TM2 domain of Cx50 protein, which impairs its trafficking to the cell membrane and gap-junction function, is associated with the cataract formation in this Chinese pedigree.
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Affiliation(s)
- Xiukun Cui
- 1 Joint National Laboratory for Antibody Drug Engineering, Henan International Union Laboratory of Antibody Medicine, Department of Cell Biology and Genetics, Henan University School of Medicine , Kaifeng, China
| | - Zheng Zhou
- 1 Joint National Laboratory for Antibody Drug Engineering, Henan International Union Laboratory of Antibody Medicine, Department of Cell Biology and Genetics, Henan University School of Medicine , Kaifeng, China
| | - Keke Zhu
- 2 Kaifeng Key Lab of Cataract and Myopia, Institute of Eye Diseases , Kaifeng Centre Hospital, Kaifeng, China
| | - Ruiping Feng
- 1 Joint National Laboratory for Antibody Drug Engineering, Henan International Union Laboratory of Antibody Medicine, Department of Cell Biology and Genetics, Henan University School of Medicine , Kaifeng, China
| | - Jiuli Han
- 1 Joint National Laboratory for Antibody Drug Engineering, Henan International Union Laboratory of Antibody Medicine, Department of Cell Biology and Genetics, Henan University School of Medicine , Kaifeng, China
| | - Mengyuan Li
- 1 Joint National Laboratory for Antibody Drug Engineering, Henan International Union Laboratory of Antibody Medicine, Department of Cell Biology and Genetics, Henan University School of Medicine , Kaifeng, China
| | - Shuangfeng Wang
- 1 Joint National Laboratory for Antibody Drug Engineering, Henan International Union Laboratory of Antibody Medicine, Department of Cell Biology and Genetics, Henan University School of Medicine , Kaifeng, China
| | - Jing Li
- 1 Joint National Laboratory for Antibody Drug Engineering, Henan International Union Laboratory of Antibody Medicine, Department of Cell Biology and Genetics, Henan University School of Medicine , Kaifeng, China
| | - Jing Zhang
- 1 Joint National Laboratory for Antibody Drug Engineering, Henan International Union Laboratory of Antibody Medicine, Department of Cell Biology and Genetics, Henan University School of Medicine , Kaifeng, China
| | - Qiying Jiang
- 1 Joint National Laboratory for Antibody Drug Engineering, Henan International Union Laboratory of Antibody Medicine, Department of Cell Biology and Genetics, Henan University School of Medicine , Kaifeng, China
| | - Wanting Zhang
- 2 Kaifeng Key Lab of Cataract and Myopia, Institute of Eye Diseases , Kaifeng Centre Hospital, Kaifeng, China
| | - Hongmei Mu
- 2 Kaifeng Key Lab of Cataract and Myopia, Institute of Eye Diseases , Kaifeng Centre Hospital, Kaifeng, China
| | - Yutao Liu
- 3 Department of Cell Biology and Anatomy, Augusta University , Augusta, Georgia
| | - Yanzhong Hu
- 1 Joint National Laboratory for Antibody Drug Engineering, Henan International Union Laboratory of Antibody Medicine, Department of Cell Biology and Genetics, Henan University School of Medicine , Kaifeng, China .,2 Kaifeng Key Lab of Cataract and Myopia, Institute of Eye Diseases , Kaifeng Centre Hospital, Kaifeng, China
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Vidya NG, Rajkumar S, Vasavada AR. Genetic investigation of ocular developmental genes in 52 patients with anophthalmia/microphthalmia. Ophthalmic Genet 2018; 39:344-352. [DOI: 10.1080/13816810.2018.1436184] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Nair Gopinathan Vidya
- Department of Molecular Genetics & Biochemistry, Iladevi Cataract & IOL Research Centre, Ahmedabad, India
- Research scholar, Manipal University, Karnataka
| | - Sankaranarayanan Rajkumar
- Department of Molecular Genetics & Biochemistry, Iladevi Cataract & IOL Research Centre, Ahmedabad, India
| | - Abhay R. Vasavada
- Department of Cataract and Refractive Surgery, Raghudeep Eye Hospital, Ahmedabad, India
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13
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Shahidullah M, Mandal A, Delamere NA. A Role for Calcium-Activated Adenylate Cyclase and Protein Kinase A in the Lens Src Family Kinase and Na,K-ATPase Response to Hyposmotic Stress. Invest Ophthalmol Vis Sci 2017; 58:4447-4456. [PMID: 28863406 PMCID: PMC6108779 DOI: 10.1167/iovs.17-21600] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose Na,K-ATPase activity in lens epithelium is subject to control by Src family tyrosine kinases (SFKs). Previously we showed hyposmotic solution causes an SFK-dependent increase in Na,K-ATPase activity in the epithelium. Here we explored the role of cAMP in the signaling mechanism responsible for the SFK and Na,K-ATPase response. Methods Intact porcine lenses were exposed to hyposmotic Krebs solution (200 mOsm) then the epithelium was assayed for cAMP, SFK phosphorylation (activation) or Na,K-ATPase activity. Results An increase of cAMP was observed in the epithelium of lenses exposed to hyposmotic solution. In lenses exposed to hyposmotic solution SFK phosphorylation in the epithelium approximately doubled as did Na,K-ATPase activity and both responses were prevented by H89, a protein kinase A inhibitor. The magnitude of the SFK response to hyposmotic solution was reduced by a TRPV4 antagonist HC067047 added to prevent TRPV4-mediated calcium entry, and by a cytoplasmic Ca2+ chelator BAPTA-AM. The Na,K-ATPase activity response in the epithelium of lenses exposed to hyposmotic solution was abolished by BAPTA-AM. As a direct test of cAMP-dependent SFK activation, intact lenses were exposed to 8-pCPT-cAMP, a cell-permeable cAMP analog. 8-pCPT-cAMP caused robust SFK activation. Using Western blot, two calcium-activated adenylyl cyclases, ADCY3 and ADCY8, were detected in lens epithelium. Conclusions Calcium-activated adenylyl cyclases are expressed in the lens epithelium and SFK activation is linked to a rise of cAMP that occurs upon hyposmotic challenge. The findings point to cAMP as a link between TRPV4 channel-mediated calcium entry, SFK activation, and a subsequent increase of Na,K-ATPase activity.
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Affiliation(s)
- Mohammad Shahidullah
- Department of Physiology, University of Arizona, Tucson, Arizona, United States.,Department of Ophthalmology & Vision Science, University of Arizona, Tucson, Arizona, United States
| | - Amritlal Mandal
- Department of Physiology, University of Arizona, Tucson, Arizona, United States
| | - Nicholas A Delamere
- Department of Physiology, University of Arizona, Tucson, Arizona, United States.,Department of Ophthalmology & Vision Science, University of Arizona, Tucson, Arizona, United States
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14
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Cui XK, Zhu KK, Zhou Z, Wan SM, Dong Y, Wang XC, Li J, Zhang J, Mu HM, Qin L, Hu YZ. A novel frameshift mutation in CX46 associated with hereditary dominant cataracts in a Chinese family. Int J Ophthalmol 2017; 10:684-690. [PMID: 28546921 DOI: 10.18240/ijo.2017.05.04] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Accepted: 02/23/2017] [Indexed: 12/20/2022] Open
Abstract
AIM To investigate the genetic mutations that are associated the hereditary autosomal dominant cataract in a Chinese family. METHODS A Chinese family consisting of 20 cataract patients (including 9 male and 11 female) and 2 unaffected individuals from 5 generations were diagnosed to be a typical autosomal dominant cataract pedigree. Genomic DNA samples were extracted from the peripheral blood cells of the participants in this pedigree. Exon sequence was used for genetic mutation screening. In silico analysis was used to study the structure characteristics of connexin 46 (CX46) mutant. Immunoblotting was conduceted for testing the expression of CX46. RESULTS To determine the involved genetic mutations, 11 well-known cataract-associated genes (cryaa, cryab, crybb1, crybb2, crygc, crygd, Gja3, Gja8, Hsf4, Mip and Pitx3) were chosen for genetic mutation test by using exon sequencing. A novel cytosine insertion at position 1195 of CX46 cDNA (c.1194_1195ins C) was found in the samples of 5 tested cataract patients but not in the unaffected 2 individuals nor in normal controls, which resulted in 30 amino acids more extension in CX46C-terminus (cx46fs400) compared with the wild-type CX46. In silico protein structure analysis indicated that the mutant showed distinctive hydrophobicity and protein secondary structure compared with the wild-type CX46. The immunoblot results revealed that CX46 protein, which expressed in the aging cataract lens tissues, was absence in the proband lens. In contrast, CX50, alpha A-crystallin and alphaB-crystallin expressed equally in both proband and aging cataract tissues. Those results revealed that the cx46fs400 mutation could impair CX46 protein expression. CONCLUSION The insertion of cytosine at position 1195 of CX46 cDNA is a novel mutation site that is associated with the autosomal dominant cataracts in this Chinese family. The C-terminal frameshift mutation is involved in regulating CX46 protein expression.
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Affiliation(s)
- Xiu-Kun Cui
- Henan International Union Laboratory of Antibody Medicine, Department of Cell biology and Genetics, Henan University School of Medicine, Kaifeng 475004, Henan Province, China
| | - Ke-Ke Zhu
- Kaifeng Key Lab of Cataract and Myopia, Institute of Eye Diseases, Kaifeng Centre Hospital, Kaifeng 475000, Henan Province, China
| | - Zheng Zhou
- Henan International Union Laboratory of Antibody Medicine, Department of Cell biology and Genetics, Henan University School of Medicine, Kaifeng 475004, Henan Province, China
| | - Si-Min Wan
- Henan International Union Laboratory of Antibody Medicine, Department of Cell biology and Genetics, Henan University School of Medicine, Kaifeng 475004, Henan Province, China
| | - Yi Dong
- Henan International Union Laboratory of Antibody Medicine, Department of Cell biology and Genetics, Henan University School of Medicine, Kaifeng 475004, Henan Province, China
| | - Xuan-Ce Wang
- Henan International Union Laboratory of Antibody Medicine, Department of Cell biology and Genetics, Henan University School of Medicine, Kaifeng 475004, Henan Province, China
| | - Jing Li
- Henan International Union Laboratory of Antibody Medicine, Department of Cell biology and Genetics, Henan University School of Medicine, Kaifeng 475004, Henan Province, China
| | - Jing Zhang
- Henan International Union Laboratory of Antibody Medicine, Department of Cell biology and Genetics, Henan University School of Medicine, Kaifeng 475004, Henan Province, China
| | - Hong-Mei Mu
- Kaifeng Key Lab of Cataract and Myopia, Institute of Eye Diseases, Kaifeng Centre Hospital, Kaifeng 475000, Henan Province, China
| | - Lei Qin
- Department of Cardiovascular Medicine, Kaifeng Centre Hospital, Kaifeng 475000, Henan Province, China
| | - Yan-Zhong Hu
- Henan International Union Laboratory of Antibody Medicine, Department of Cell biology and Genetics, Henan University School of Medicine, Kaifeng 475004, Henan Province, China
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15
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White JPM, Cibelli M, Urban L, Nilius B, McGeown JG, Nagy I. TRPV4: Molecular Conductor of a Diverse Orchestra. Physiol Rev 2017; 96:911-73. [PMID: 27252279 DOI: 10.1152/physrev.00016.2015] [Citation(s) in RCA: 259] [Impact Index Per Article: 37.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Transient receptor potential vanilloid type 4 (TRPV4) is a calcium-permeable nonselective cation channel, originally described in 2000 by research teams led by Schultz (Nat Cell Biol 2: 695-702, 2000) and Liedtke (Cell 103: 525-535, 2000). TRPV4 is now recognized as being a polymodal ionotropic receptor that is activated by a disparate array of stimuli, ranging from hypotonicity to heat and acidic pH. Importantly, this ion channel is constitutively expressed and capable of spontaneous activity in the absence of agonist stimulation, which suggests that it serves important physiological functions, as does its widespread dissemination throughout the body and its capacity to interact with other proteins. Not surprisingly, therefore, it has emerged more recently that TRPV4 fulfills a great number of important physiological roles and that various disease states are attributable to the absence, or abnormal functioning, of this ion channel. Here, we review the known characteristics of this ion channel's structure, localization and function, including its activators, and examine its functional importance in health and disease.
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Affiliation(s)
- John P M White
- Anaesthetics, Pain Medicine and Intensive Care Section, Department of Surgery and Cancer, Imperial College London, London, United Kingdom; Department of Anaesthetics, The Queen Elizabeth Hospital, Birmingham, United Kingdom; Academic Department of Anaesthesia and Intensive Care Medicine, School of Clinical and Experimental Medicine, University of Birmingham, Birmingham, United Kingdom; Preclinical Secondary Pharmacology, Preclinical Safety, Novartis Institute for Biomedical Research, Cambridge, Massachusetts; Laboratory of Ion Channel Research, Department of Cellular and Molecular Medicine, KU Leuven, Campus Gasthuisberg, Leuven, Belgium; and School of Medicine, Dentistry and Biomedical Science, Queen's University Belfast, Belfast, United Kingdom
| | - Mario Cibelli
- Anaesthetics, Pain Medicine and Intensive Care Section, Department of Surgery and Cancer, Imperial College London, London, United Kingdom; Department of Anaesthetics, The Queen Elizabeth Hospital, Birmingham, United Kingdom; Academic Department of Anaesthesia and Intensive Care Medicine, School of Clinical and Experimental Medicine, University of Birmingham, Birmingham, United Kingdom; Preclinical Secondary Pharmacology, Preclinical Safety, Novartis Institute for Biomedical Research, Cambridge, Massachusetts; Laboratory of Ion Channel Research, Department of Cellular and Molecular Medicine, KU Leuven, Campus Gasthuisberg, Leuven, Belgium; and School of Medicine, Dentistry and Biomedical Science, Queen's University Belfast, Belfast, United Kingdom
| | - Laszlo Urban
- Anaesthetics, Pain Medicine and Intensive Care Section, Department of Surgery and Cancer, Imperial College London, London, United Kingdom; Department of Anaesthetics, The Queen Elizabeth Hospital, Birmingham, United Kingdom; Academic Department of Anaesthesia and Intensive Care Medicine, School of Clinical and Experimental Medicine, University of Birmingham, Birmingham, United Kingdom; Preclinical Secondary Pharmacology, Preclinical Safety, Novartis Institute for Biomedical Research, Cambridge, Massachusetts; Laboratory of Ion Channel Research, Department of Cellular and Molecular Medicine, KU Leuven, Campus Gasthuisberg, Leuven, Belgium; and School of Medicine, Dentistry and Biomedical Science, Queen's University Belfast, Belfast, United Kingdom
| | - Bernd Nilius
- Anaesthetics, Pain Medicine and Intensive Care Section, Department of Surgery and Cancer, Imperial College London, London, United Kingdom; Department of Anaesthetics, The Queen Elizabeth Hospital, Birmingham, United Kingdom; Academic Department of Anaesthesia and Intensive Care Medicine, School of Clinical and Experimental Medicine, University of Birmingham, Birmingham, United Kingdom; Preclinical Secondary Pharmacology, Preclinical Safety, Novartis Institute for Biomedical Research, Cambridge, Massachusetts; Laboratory of Ion Channel Research, Department of Cellular and Molecular Medicine, KU Leuven, Campus Gasthuisberg, Leuven, Belgium; and School of Medicine, Dentistry and Biomedical Science, Queen's University Belfast, Belfast, United Kingdom
| | - J Graham McGeown
- Anaesthetics, Pain Medicine and Intensive Care Section, Department of Surgery and Cancer, Imperial College London, London, United Kingdom; Department of Anaesthetics, The Queen Elizabeth Hospital, Birmingham, United Kingdom; Academic Department of Anaesthesia and Intensive Care Medicine, School of Clinical and Experimental Medicine, University of Birmingham, Birmingham, United Kingdom; Preclinical Secondary Pharmacology, Preclinical Safety, Novartis Institute for Biomedical Research, Cambridge, Massachusetts; Laboratory of Ion Channel Research, Department of Cellular and Molecular Medicine, KU Leuven, Campus Gasthuisberg, Leuven, Belgium; and School of Medicine, Dentistry and Biomedical Science, Queen's University Belfast, Belfast, United Kingdom
| | - Istvan Nagy
- Anaesthetics, Pain Medicine and Intensive Care Section, Department of Surgery and Cancer, Imperial College London, London, United Kingdom; Department of Anaesthetics, The Queen Elizabeth Hospital, Birmingham, United Kingdom; Academic Department of Anaesthesia and Intensive Care Medicine, School of Clinical and Experimental Medicine, University of Birmingham, Birmingham, United Kingdom; Preclinical Secondary Pharmacology, Preclinical Safety, Novartis Institute for Biomedical Research, Cambridge, Massachusetts; Laboratory of Ion Channel Research, Department of Cellular and Molecular Medicine, KU Leuven, Campus Gasthuisberg, Leuven, Belgium; and School of Medicine, Dentistry and Biomedical Science, Queen's University Belfast, Belfast, United Kingdom
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16
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Del Rio R, Quintanilla RA, Orellana JA, Retamal MA. Neuron-Glia Crosstalk in the Autonomic Nervous System and Its Possible Role in the Progression of Metabolic Syndrome: A New Hypothesis. Front Physiol 2015; 6:350. [PMID: 26648871 PMCID: PMC4664731 DOI: 10.3389/fphys.2015.00350] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Accepted: 11/09/2015] [Indexed: 01/26/2023] Open
Abstract
Metabolic syndrome (MS) is characterized by the following physiological alterations: increase in abdominal fat, insulin resistance, high concentration of triglycerides, low levels of HDL, high blood pressure, and a generalized inflammatory state. One of the pathophysiological hallmarks of this syndrome is the presence of neurohumoral activation, which involve autonomic imbalance associated to hyperactivation of the sympathetic nervous system. Indeed, enhanced sympathetic drive has been linked to the development of endothelial dysfunction, hypertension, stroke, myocardial infarct, and obstructive sleep apnea. Glial cells, the most abundant cells in the central nervous system, control synaptic transmission, and regulate neuronal function by releasing bioactive molecules called gliotransmitters. Recently, a new family of plasma membrane channels called hemichannels has been described to allow the release of gliotransmitters and modulate neuronal firing rate. Moreover, a growing amount of evidence indicates that uncontrolled hemichannel opening could impair glial cell functions, affecting synaptic transmission and neuronal survival. Given that glial cell functions are disturbed in various metabolic diseases, we hypothesize that progression of MS may relies on hemichannel-dependent impairment of glial-to-neuron communication by a mechanism related to dysfunction of inflammatory response and mitochondrial metabolism of glial cells. In this manuscript, we discuss how glial cells may contribute to the enhanced sympathetic drive observed in MS, and shed light about the possible role of hemichannels in this process.
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Affiliation(s)
- Rodrigo Del Rio
- Centro de Investigación Biomédica, Universidad Autónoma de Chile Santiago, Chile ; Dirección de Investigación, Universidad Científica del Sur Lima, Perú
| | | | - Juan A Orellana
- Departamento de Neurología, Escuela de Medicina, Pontificia Universidad Católica de Chile Santiago, Chile
| | - Mauricio A Retamal
- Centro de Fisiología Celular e Integrativa, Facultad de Medicina. Clínica Alemana Universidad del Desarrollo Santiago, Chile
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17
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Shahidullah M, Mandal A, Delamere NA. Damage to lens fiber cells causes TRPV4-dependent Src family kinase activation in the epithelium. Exp Eye Res 2015; 140:85-93. [PMID: 26318609 DOI: 10.1016/j.exer.2015.08.013] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2015] [Revised: 08/08/2015] [Accepted: 08/17/2015] [Indexed: 11/25/2022]
Abstract
The bulk of the lens consists of tightly packed fiber cells. Because mature lens fibers lack mitochondria and other organelles, lens homeostasis relies on a monolayer of epithelial cells at the anterior surface. The detection of various signaling pathways in lens epithelial cells suggests they respond to stimuli that influence lens function. Focusing on Src Family Kinases (SFKs) and Transient Receptor Potential Vanilloid 4 (TRPV4), we tested whether the epithelium can sense and respond to an event that occurs in fiber mass. The pig lens was subjected to localized freeze-thaw (FT) damage to fibers at posterior pole then the lens was incubated for 1-10 min in Krebs solution at 37 °C. Transient SFK activation in the epithelium was detectable at 1 min. Using a western blot approach, the ion channel TRPV4 was detected in the epithelium but was sparse or absent in fiber cells. Even though TRPV4 expression appears low at the actual site of FT damage to the fibers, SFK activation in the epithelium was suppressed in lenses subjected to FT damage then incubated with the TRPV4 antagonist HC067047 (10 μM). Na,K-ATPase activity was examined because previous studies report changes of Na,K-ATPase activity associated with SFK activation. Na,K-ATPase activity doubled in the epithelium removed from FT-damaged lenses and the response was prevented by HC067047 or the SFK inhibitor PP2 (10 μM). Similar changes were observed in response to fiber damage caused by injection of 5 μl hyperosmotic NaCl or mannitol solution beneath the surface of the posterior pole. The findings point to a TRPV4-dependent mechanism that enables the epithelial cells to detect remote damage in the fiber mass and respond within minutes by activating SFK and increasing Na,K-ATPase activity. Because TRPV4 channels are mechanosensitive, we speculate they may be stimulated by swelling of the lens structure caused by damage to the fibers. Increased Na,K-ATPase activity gives the lens greater capacity to control ion concentrations in the fiber mass and the Na,K-ATPase response may reflect the critical contribution of the epithelium to lens ion homeostasis.
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Affiliation(s)
- M Shahidullah
- Dept. of Physiology, University of Arizona, 1501 N Campbell Avenue, Tucson, AZ, 85724, USA.
| | - A Mandal
- Dept. of Physiology, University of Arizona, 1501 N Campbell Avenue, Tucson, AZ, 85724, USA
| | - N A Delamere
- Dept. of Physiology, University of Arizona, 1501 N Campbell Avenue, Tucson, AZ, 85724, USA
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18
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Kibschull M, Gellhaus A, Carette D, Segretain D, Pointis G, Gilleron J. Physiological roles of connexins and pannexins in reproductive organs. Cell Mol Life Sci 2015; 72:2879-98. [PMID: 26100514 PMCID: PMC11114083 DOI: 10.1007/s00018-015-1965-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2015] [Accepted: 06/11/2015] [Indexed: 12/15/2022]
Abstract
Reproductive organs are complex and well-structured tissues essential to perpetuate the species. In mammals, the male and female reproductive organs vary on their organization, morphology and function. Connectivity between cells in such tissues plays pivotal roles in organogenesis and tissue functions through the regulation of cellular proliferation, migration, differentiation and apoptosis. Connexins and pannexins can be seen as major regulators of these physiological processes. In the present review, we assembled several lines of evidence demonstrating that these two families of proteins are essential for male and female reproduction.
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Affiliation(s)
- Mark Kibschull
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, 25 Orde Street, Toronto, M5T 3H7 Canada
| | - Alexandra Gellhaus
- Department of Gynecology and Obstetrics, University of Duisburg-Essen, Hufelandstrasse 55, 45122 Essen, Germany
| | - Diane Carette
- UMR S1147, University Paris Descartes, 45 rue des Saints-Pères, 75006 Paris, France
- University of Versailles, 78035 Saint Quentin, France
- INSERM U 1065, University of Nice Sophia-Antipolis, 151 Route Saint-Antoine de Ginestière, BP 2 3194, 06204 Nice Cedex 3, France
| | - Dominique Segretain
- UMR S1147, University Paris Descartes, 45 rue des Saints-Pères, 75006 Paris, France
- University of Versailles, 78035 Saint Quentin, France
| | - Georges Pointis
- INSERM U 1065, University of Nice Sophia-Antipolis, 151 Route Saint-Antoine de Ginestière, BP 2 3194, 06204 Nice Cedex 3, France
| | - Jerome Gilleron
- INSERM U 1065, University of Nice Sophia-Antipolis, 151 Route Saint-Antoine de Ginestière, BP 2 3194, 06204 Nice Cedex 3, France
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19
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Retamal MA, Reyes EP, García IE, Pinto B, Martínez AD, González C. Diseases associated with leaky hemichannels. Front Cell Neurosci 2015; 9:267. [PMID: 26283912 PMCID: PMC4515567 DOI: 10.3389/fncel.2015.00267] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2015] [Accepted: 06/29/2015] [Indexed: 01/10/2023] Open
Abstract
Hemichannels (HCs) and gap junction channels (GJCs) formed by protein subunits called connexins (Cxs) are major pathways for intercellular communication. While HCs connect the intracellular compartment with the extracellular milieu, GJCs allow the interchange of molecules between cytoplasm of two contacting cells. Under physiological conditions, HCs are mostly closed, but they can open under certain stimuli allowing the release of autocrine and paracrine molecules. Moreover, some pathological conditions, like ischemia or other inflammation conditions, significantly increase HCs activity. In addition, some mutations in Cx genes associated with human diseases, such as deafness or cataracts, lead to the formation of more active HCs or “leaky HCs.” In this article we will revise cellular and molecular mechanisms underlying the appearance of leaky HCs, and the consequences of their expression in different cellular systems and animal models, in seeking a common pattern or pathological mechanism of disease.
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Affiliation(s)
- Mauricio A Retamal
- Centro de Fisiología Celular e Integrativa, Facultad de Medicina, Clínica Alemana Universidad del Desarrollo Santiago, Chile
| | - Edison P Reyes
- Centro de Fisiología Celular e Integrativa, Facultad de Medicina, Clínica Alemana Universidad del Desarrollo Santiago, Chile ; Centro de Investigación Biomédica, Universidad Autónoma de Chile Santiago, Chile
| | - Isaac E García
- Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaíso Valparaíso, Chile
| | - Bernardo Pinto
- Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaíso Valparaíso, Chile
| | - Agustín D Martínez
- Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaíso Valparaíso, Chile
| | - Carlos González
- Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaíso Valparaíso, Chile
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