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Zhang X, Wang F, Su Y. TRPV: An emerging target in glaucoma and optic nerve damage. Exp Eye Res 2024; 239:109784. [PMID: 38199261 DOI: 10.1016/j.exer.2024.109784] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Revised: 11/30/2023] [Accepted: 01/06/2024] [Indexed: 01/12/2024]
Abstract
Transient receptor potential vanilloid (TRPV) channels are members of the TRP channel superfamily, which are ion channels that sense mechanical and osmotic stimuli and participate in Ca2+ signalling across the cell membrane. TRPV channels play important roles in maintaining the normal functions of an organism, and defects or abnormalities in TRPV channel function cause a range of diseases, including cardiovascular, neurological and urological disorders. Glaucoma is a group of chronic progressive optic nerve diseases with pathological changes that can occur in the tissues of the anterior and posterior segments of the eye, including the ciliary body, trabecular meshwork, Schlemm's canal, and retina. TRPV channels are expressed in these tissues and play various roles in glaucoma. In this article, we review various aspects of the pathogenesis of glaucoma, the structure and function of TRPV channels, the relationship between TRPV channels and systemic diseases, and the relationship between TRPV channels and ocular diseases, especially glaucoma, and we suggest future research directions. This information will help to further our understanding of TRPV channels and provide new ideas and targets for the treatment of glaucoma and optic nerve damage.
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Affiliation(s)
- Xiaotong Zhang
- Department of Ophthalmology, The Fourth Affiliated Hospital, Harbin Medical University, Harbin, China
| | - Feng Wang
- Department of Ophthalmology, The Fourth Affiliated Hospital, Harbin Medical University, Harbin, China.
| | - Ying Su
- Eye Hospital, The First Affiliated Hospital, Harbin Medical University, Harbin, China.
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Lindner T, Schmidl D, Peschorn L, Pai V, Popa-Cherecheanu A, Chua J, Schmetterer L, Garhöfer G. Therapeutic Potential of Cannabinoids in Glaucoma. Pharmaceuticals (Basel) 2023; 16:1149. [PMID: 37631064 PMCID: PMC10460067 DOI: 10.3390/ph16081149] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2023] [Revised: 08/07/2023] [Accepted: 08/09/2023] [Indexed: 08/27/2023] Open
Abstract
Glaucoma is a leading cause of irreversible blindness worldwide. To date, intraocular pressure (IOP) is the only modifiable risk factor in glaucoma treatment, but even in treated patients, the disease can progress. Cannabinoids, which have been known to lower IOP since the 1970s, have been shown to have beneficial effects in glaucoma patients beyond their IOP-lowering properties. In addition to the classical cannabinoid receptors CB1 and CB2, knowledge of non-classical cannabinoid receptors and the endocannabinoid system has increased in recent years. In particular, the CB2 receptor has been shown to mediate anti-inflammatory, anti-apoptotic, and neuroprotective properties, which may represent a promising therapeutic target for neuroprotection in glaucoma patients. Due to their vasodilatory effects, cannabinoids improve blood flow to the optic nerve head, which may suggest a vasoprotective potential and counteract the altered blood flow observed in glaucoma patients. The aim of this review was to assess the available evidence on the effects and therapeutic potential of cannabinoids in glaucoma patients. The pharmacological mechanisms underlying the effects of cannabinoids on IOP, neuroprotection, and ocular hemodynamics have been discussed.
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Affiliation(s)
- Theresa Lindner
- Department of Clinical Pharmacology, Medical University Vienna, 1090 Vienna, Austria; (T.L.); (D.S.); (L.P.); (V.P.); (L.S.)
| | - Doreen Schmidl
- Department of Clinical Pharmacology, Medical University Vienna, 1090 Vienna, Austria; (T.L.); (D.S.); (L.P.); (V.P.); (L.S.)
| | - Laura Peschorn
- Department of Clinical Pharmacology, Medical University Vienna, 1090 Vienna, Austria; (T.L.); (D.S.); (L.P.); (V.P.); (L.S.)
| | - Viktoria Pai
- Department of Clinical Pharmacology, Medical University Vienna, 1090 Vienna, Austria; (T.L.); (D.S.); (L.P.); (V.P.); (L.S.)
| | - Alina Popa-Cherecheanu
- Department of Ophthalmology, Emergency University Hospital, 050098 Bucharest, Romania;
- Carol Davila University of Medicine and Pharmacy, 020021 Bucharest, Romania
| | - Jacqueline Chua
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore 169856, Singapore;
- Ophthalmology and Visual Sciences Academic Clinical Program, Duke-NUS Medical School, Singapore 169857, Singapore
| | - Leopold Schmetterer
- Department of Clinical Pharmacology, Medical University Vienna, 1090 Vienna, Austria; (T.L.); (D.S.); (L.P.); (V.P.); (L.S.)
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore 169856, Singapore;
- Ophthalmology and Visual Sciences Academic Clinical Program, Duke-NUS Medical School, Singapore 169857, Singapore
- SERI-NTU Advanced Ocular Engineering (STANCE), Nanyang Technological University, Singapore 639798, Singapore
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, Singapore 637459, Singapore
- Center for Medical Physics and Biomedical Engineering, Medical University Vienna, 1090 Vienna, Austria
- Institute of Molecular and Clinical Ophthalmology, 4031 Basel, Switzerland
| | - Gerhard Garhöfer
- Department of Clinical Pharmacology, Medical University Vienna, 1090 Vienna, Austria; (T.L.); (D.S.); (L.P.); (V.P.); (L.S.)
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CB 1R, CB 2R and TRPV1 expression and modulation in in vivo, animal glaucoma models: A systematic review. Biomed Pharmacother 2022; 150:112981. [PMID: 35468582 DOI: 10.1016/j.biopha.2022.112981] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Revised: 04/06/2022] [Accepted: 04/14/2022] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND The endocannabinoid system (ECS) is a complex biological regulatory system. Its expression and functionality have been widely investigated in ocular tissues. Recent data have reported its modulation to be valid in determining an ocular hypotensive and a neuroprotective effect in preclinical animal models of glaucoma. AIM This study aimed to explore the available literature on cannabinoid receptor 1 (CB1R), cannabinoid receptor 2 (CB2R), and transient receptor potential vanilloid 1 (TRPV1) expression in the trabecular meshwork (TM), ciliary body (CB), and retina as well as their ocular hypotensive and neuroprotective effects in preclinical, in vivo, animal glaucoma models. MATERIALS AND METHODS The study adhered to both PRISMA and SYRCLE guidelines. Sixty-nine full-length articles were included in the final analysis. RESULTS Preclinical studies indicated a widespread distribution of CB1R, CB2R, and TRPV1 in the TM, CB, and retina, although receptor-, age-, and species-dependent differences were observed. CB1R and CB2R modulation have been shown to exert ocular hypotensive effects in preclinical models via the regulation of inflow and outflow pathways. Retinal cell neuroprotection has been achieved in several experimental models, mediated by agonists and antagonists of CB1R, CB2R, and TRPV1. DISCUSSION Despite the growing body of preclinical data regarding the expression and modulation of ECS in ocular tissues, the mechanisms responsible for the hypotensive and neuroprotective efficacy exerted by this system remain largely elusive. Research on this topic is advocated to further substantiate the hypothesis that the ECS is a new potential therapeutic target in the context of glaucoma.
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Rapino C, Tortolani D, Scipioni L, Maccarrone M. Neuroprotection by (endo)Cannabinoids in Glaucoma and Retinal Neurodegenerative Diseases. Curr Neuropharmacol 2018; 16:959-970. [PMID: 28738764 PMCID: PMC6120105 DOI: 10.2174/1570159x15666170724104305] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Revised: 07/14/2017] [Accepted: 07/21/2017] [Indexed: 01/10/2023] Open
Abstract
BACKGROUND Emerging neuroprotective strategies are being explored to preserve the retina from degeneration, that occurs in eye pathologies like glaucoma, diabetic retinopathy, age-related macular degeneration, and retinitis pigmentosa. Incidentally, neuroprotection of retina is a defending mechanism designed to prevent or delay neuronal cell death, and to maintain neural function following an initial insult, thus avoiding loss of vision. METHODS Numerous studies have investigated potential neuroprotective properties of plant-derived phytocannabinoids, as well as of their endogenous counterparts collectively termed endocannabinoids (eCBs), in several degenerative diseases of the retina. eCBs are a group of neuromodulators that, mainly by activating G protein-coupled type-1 and type-2 cannabinoid (CB1 and CB2) receptors, trigger multiple signal transduction cascades that modulate central and peripheral cell functions. A fine balance between biosynthetic and degrading enzymes that control the right concentration of eCBs has been shown to provide neuroprotection in traumatic, ischemic, inflammatory and neurotoxic damage of the brain. RESULTS Since the existence of eCBs and their binding receptors was documented in the retina of numerous species (from fishes to primates), their involvement in the visual processing has been demonstrated, more recently with a focus on retinal neurodegeneration and neuroprotection. CONCLUSION The aim of this review is to present a modern view of the endocannabinoid system, in order to discuss in a better perspective available data from preclinical studies on the use of eCBs as new neuroprotective agents, potentially useful to prevent glaucoma and retinal neurodegenerative diseases.
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Affiliation(s)
- Cinzia Rapino
- Address correspondence to these authors at the Faculty of Veterinary Medicine, University of Teramo, 64100 Teramo, Italy; Tel: +39 0861 266842;, E-mail: and the Department of Medicine, Campus Bio-Medico University of Rome, 00128 Rome, Italy; Tel: +39 06 225419169;, E-mail:
| | | | | | - Mauro Maccarrone
- Address correspondence to these authors at the Faculty of Veterinary Medicine, University of Teramo, 64100 Teramo, Italy; Tel: +39 0861 266842;, E-mail: and the Department of Medicine, Campus Bio-Medico University of Rome, 00128 Rome, Italy; Tel: +39 06 225419169;, E-mail:
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Krishnatreyya H, Hazarika H, Saha A, Chattopadhyay P. Capsaicin, the primary constituent of pepper sprays and its pharmacological effects on mammalian ocular tissues. Eur J Pharmacol 2018; 819:114-121. [DOI: 10.1016/j.ejphar.2017.11.042] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Revised: 11/20/2017] [Accepted: 11/24/2017] [Indexed: 01/07/2023]
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Kong WL, Peng YY, Peng BW. Modulation of neuroinflammation: Role and therapeutic potential of TRPV1 in the neuro-immune axis. Brain Behav Immun 2017; 64:354-366. [PMID: 28342781 DOI: 10.1016/j.bbi.2017.03.007] [Citation(s) in RCA: 68] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Revised: 03/04/2017] [Accepted: 03/14/2017] [Indexed: 02/07/2023] Open
Abstract
Transient receptor potential vanilloid type 1 channel (TRPV1), as a ligand-gated non-selective cation channel, has recently been demonstrated to have wide expression in the neuro-immune axis, where its multiple functions occur through regulation of both neuronal and non-neuronal activities. Growing evidence has suggested that TRPV1 is functionally expressed in glial cells, especially in the microglia and astrocytes. Glial cells perform immunological functions in response to pathophysiological challenges through pro-inflammatory or anti-inflammatory cytokines and chemokines in which TRPV1 is involved. Sustaining inflammation might mediate a positive feedback loop of neuroinflammation and exacerbate neurological disorders. Accumulating evidence has suggested that TRPV1 is closely related to immune responses and might be recognized as a molecular switch in the neuroinflammation of a majority of seizures and neurodegenerative diseases. In this review, we evidenced that inflammation modulates the expression and activity of TRPV1 in the central nervous system (CNS) and TRPV1 exerts reciprocal actions over neuroinflammatory processes. Together, the literature supports the hypothesis that TRPV1 may represent potential therapeutic targets in the neuro-immune axis.
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Affiliation(s)
- Wei-Lin Kong
- Department of Physiology, Hubei Provincial Key Laboratory of Developmentally Originated Disorder, Hubei Province Key Laboratory of Allergy and Immunology, School of Basic Medical Sciences, Wuhan University, Wuhan, Hubei, China
| | - Yuan-Yuan Peng
- Department of Physiology, Hubei Provincial Key Laboratory of Developmentally Originated Disorder, Hubei Province Key Laboratory of Allergy and Immunology, School of Basic Medical Sciences, Wuhan University, Wuhan, Hubei, China
| | - Bi-Wen Peng
- Department of Physiology, Hubei Provincial Key Laboratory of Developmentally Originated Disorder, Hubei Province Key Laboratory of Allergy and Immunology, School of Basic Medical Sciences, Wuhan University, Wuhan, Hubei, China.
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Cairns EA, Toguri JT, Porter RF, Szczesniak AM, Kelly MEM. Seeing over the horizon - targeting the endocannabinoid system for the treatment of ocular disease. J Basic Clin Physiol Pharmacol 2017; 27:253-65. [PMID: 26565550 DOI: 10.1515/jbcpp-2015-0065] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Accepted: 09/25/2015] [Indexed: 01/09/2023]
Abstract
The observation that marijuana reduces intraocular pressure was made by Hepler and Frank in the 1970s. Since then, there has been a significant body of work investigating cannabinoids for their potential use as therapeutics. To date, no endocannabinoid system (ECS)-modulating drug has been approved for clinical use in the eye; however, recent advances in our understanding of the ECS, as well as new pharmacological tools, has renewed interest in the development of ocular ECS-based therapeutics. This review summarizes the current state-of-affairs for the use of ECS-modulating drugs for the treatment of glaucoma and ocular inflammatory and ischemic disease.
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Sappington RM, Sidorova T, Ward NJ, Chakravarthy R, Ho KW, Calkins DJ. Activation of transient receptor potential vanilloid-1 (TRPV1) influences how retinal ganglion cell neurons respond to pressure-related stress. Channels (Austin) 2016; 9:102-13. [PMID: 25713995 DOI: 10.1080/19336950.2015.1009272] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Our recent studies implicate the transient receptor potential vanilloid-1 (TRPV1) channel as a mediator of retinal ganglion cell (RGC) function and survival. With elevated pressure in the eye, TRPV1 increases in RGCs, supporting enhanced excitability, while Trpv1 -/- accelerates RGC degeneration in mice. Here we find TRPV1 localized in monkey and human RGCs, similar to rodents. Expression increases in RGCs exposed to acute changes in pressure. In retinal explants, contrary to our animal studies, both Trpv1 -/- and pharmacological antagonism of the channel prevented pressure-induced RGC apoptosis, as did chelation of extracellular Ca(2+). Finally, while TRPV1 and TRPV4 co-localize in some RGC bodies and form a protein complex in the retina, expression of their mRNA is inversely related with increasing ocular pressure. We propose that TRPV1 activation by pressure-related insult in the eye initiates changes in expression that contribute to a Ca(2+)-dependent adaptive response to maintain excitatory signaling in RGCs.
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Affiliation(s)
- Rebecca M Sappington
- a The Vanderbilt Eye Institute and Vanderbilt Brain Institute ; Vanderbilt University School of Medicine ; Nashville , TN USA
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Reinach PS, Chen W, Mergler S. Polymodal roles of transient receptor potential channels in the control of ocular function. EYE AND VISION 2015; 2:5. [PMID: 26605361 PMCID: PMC4655450 DOI: 10.1186/s40662-015-0016-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 11/21/2014] [Accepted: 02/15/2015] [Indexed: 12/05/2022]
Abstract
Maintenance of intracellular Ca2+ levels at orders of magnitude below those in the extracellular environment is a requisite for preserving cell viability. Membrane channels contribute to such control through modulating their time-dependent opening and closing behaviour. Such regulation requires Ca2+ to serve as a second messenger mediating receptor control of numerous life-sustaining responses. Transient receptor potential (TRP) channels signal transduce a wide variety of different sensory stimuli to induce responses modulating cellular function. These channels are non-selective cation channels with variable Ca2+ selectivity having extensive sequence homology. They constitute a superfamily made up of 28 different members that are subdivided into 7 different subfamilies based on differences in sequence homology. Some of these TRP channel isotypes are expressed in the eye and localized to both neuronal and non-neuronal cell membranes. Their activation generates intracellular Ca2+ transients and other downstream-linked signalling events that affect numerous responses required for visual function. As there is an association between changes in functional TRP expression in various ocular diseases, there are efforts underway to determine if these channels can be used as drug targets to reverse declines in ocular function. We review here our current knowledge about the expression, function and regulation of TRPs in different eye tissues in health and disease. Furthermore, some of the remaining hurdles are described to developing safe and efficacious TRP channel modulators for use in a clinical setting.
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Affiliation(s)
- Peter S Reinach
- School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, Zhejiang 325027 P.R. China
| | - Weiwei Chen
- School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, Zhejiang 325027 P.R. China
| | - Stefan Mergler
- Charité-Universitätsmedizin Berlin, Campus Virchow-Klinikum, Klinik für Augenheilkunde, Augustenburger Platz 1, D-13353 Berlin, Germany
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Short-term increases in transient receptor potential vanilloid-1 mediate stress-induced enhancement of neuronal excitation. J Neurosci 2015; 34:15369-81. [PMID: 25392504 DOI: 10.1523/jneurosci.3424-14.2014] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Progression of neurodegeneration in disease and injury is influenced by the response of individual neurons to stressful stimuli and whether this response includes mechanisms to counter declining function. Transient receptor potential (TRP) cation channels transduce a variety of disease-relevant stimuli and can mediate diverse stress-dependent changes in physiology, both presynaptic and postsynaptic. Recently, we demonstrated that knock-out or pharmacological inhibition of the TRP vanilloid-1 (TRPV1) capsaicin-sensitive subunit accelerates degeneration of retinal ganglion cell neurons and their axons with elevated ocular pressure, the critical stressor in the most common optic neuropathy, glaucoma. Here we probed the mechanism of the influence of TRPV1 on ganglion cell survival in mouse models of glaucoma. We found that induced elevations of ocular pressure increased TRPV1 in ganglion cells and its colocalization at excitatory synapses to their dendrites, whereas chronic elevation progressively increased ganglion cell Trpv1 mRNA. Enhanced TRPV1 expression in ganglion cells was transient and supported a reversal of the effect of TRPV1 on ganglion cells from hyperpolarizing to depolarizing, which was also transient. Short-term enhancement of TRPV1-mediated activity led to a delayed increase in axonal spontaneous excitation that was absent in ganglion cells from Trpv1(-/-) retina. In isolated ganglion cells, pharmacologically activated TRPV1 mobilized to discrete nodes along ganglion cell dendrites that corresponded to sites of elevated Ca(2+). These results suggest that TRPV1 may promote retinal ganglion cell survival through transient enhancement of local excitation and axonal activity in response to ocular stress.
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Ryskamp DA, Redmon S, Jo AO, Križaj D. TRPV1 and Endocannabinoids: Emerging Molecular Signals that Modulate Mammalian Vision. Cells 2014; 3:914-38. [PMID: 25222270 PMCID: PMC4197638 DOI: 10.3390/cells3030914] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2014] [Revised: 08/27/2014] [Accepted: 09/05/2014] [Indexed: 01/18/2023] Open
Abstract
Transient Receptor Potential Vanilloid 1 (TRPV1) subunits form a polymodal cation channel responsive to capsaicin, heat, acidity and endogenous metabolites of polyunsaturated fatty acids. While originally reported to serve as a pain and heat detector in the peripheral nervous system, TRPV1 has been implicated in the modulation of blood flow and osmoregulation but also neurotransmission, postsynaptic neuronal excitability and synaptic plasticity within the central nervous system. In addition to its central role in nociception, evidence is accumulating that TRPV1 contributes to stimulus transduction and/or processing in other sensory modalities, including thermosensation, mechanotransduction and vision. For example, TRPV1, in conjunction with intrinsic cannabinoid signaling, might contribute to retinal ganglion cell (RGC) axonal transport and excitability, cytokine release from microglial cells and regulation of retinal vasculature. While excessive TRPV1 activity was proposed to induce RGC excitotoxicity, physiological TRPV1 activity might serve a neuroprotective function within the complex context of retinal endocannabinoid signaling. In this review we evaluate the current evidence for localization and function of TRPV1 channels within the mammalian retina and explore the potential interaction of this intriguing nociceptor with endogenous agonists and modulators.
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Affiliation(s)
- Daniel A Ryskamp
- Department of Ophthalmology & Visual Sciences, Moran Eye Institute, University of Utah School of Medicine, Salt Lake City, UT 84132, USA.
| | - Sarah Redmon
- Department of Ophthalmology & Visual Sciences, Moran Eye Institute, University of Utah School of Medicine, Salt Lake City, UT 84132, USA.
| | - Andrew O Jo
- Department of Ophthalmology & Visual Sciences, Moran Eye Institute, University of Utah School of Medicine, Salt Lake City, UT 84132, USA.
| | - David Križaj
- Department of Ophthalmology & Visual Sciences, Moran Eye Institute, University of Utah School of Medicine, Salt Lake City, UT 84132, USA.
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Ho KW, Lambert WS, Calkins DJ. Activation of the TRPV1 cation channel contributes to stress-induced astrocyte migration. Glia 2014; 62:1435-51. [PMID: 24838827 DOI: 10.1002/glia.22691] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2013] [Revised: 04/25/2014] [Accepted: 04/29/2014] [Indexed: 01/13/2023]
Abstract
Astrocytes provide metabolic, structural, and synaptic support to neurons in normal physiology and also contribute widely to pathogenic processes in response to stress or injury. Reactive astrocytes can undergo cytoskeletal reorganization and increase migration through changes in intracellular Ca(2+) mediated by a variety of potential modulators. Here we tested whether migration of isolated retinal astrocytes following mechanical injury (scratch wound) involves the transient receptor potential vanilloid-1 channel (TRPV1), which contributes to Ca(2+)-mediated cytoskeletal rearrangement and migration in other systems. Application of the TRPV1-specific antagonists, capsazepine (CPZ) or 5'-iodoresiniferatoxin (IRTX), slowed migration by as much as 44%, depending on concentration. In contrast, treatment with the TRPV1-specific agonists, capsaicin (CAP) or resiniferatoxin (RTX) produced only a slight acceleration over a range of concentrations. Chelation of extracellular Ca(2+) with EGTA (1 mM) slowed astrocyte migration by 35%. Ratiometric imaging indicated that scratch wound induced a sharp 20% rise in astrocyte Ca(2+) that dissipated with distance from the wound. Treatment with IRTX both slowed and dramatically reduced the scratch-induced Ca(2+) increase. Both CPZ and IRTX influenced astrocyte cytoskeletal organization, especially near the wound edge. Taken together, our results indicate that astrocyte mobilization in response to mechanical stress involves influx of extracellular Ca(2+) and cytoskeletal changes in part mediated by TRPV1 activation.
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Affiliation(s)
- Karen W Ho
- Vanderbilt Department of Pharmacology, Vanderbilt University Medical Center, Nashville, Tennessee
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Gonçalves A, Marques C, Leal E, Ribeiro CF, Reis F, Ambrósio AF, Fernandes R. Dipeptidyl peptidase-IV inhibition prevents blood-retinal barrier breakdown, inflammation and neuronal cell death in the retina of type 1 diabetic rats. Biochim Biophys Acta Mol Basis Dis 2014; 1842:1454-63. [PMID: 24769045 DOI: 10.1016/j.bbadis.2014.04.013] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2013] [Revised: 04/04/2014] [Accepted: 04/11/2014] [Indexed: 12/21/2022]
Abstract
Diabetic retinopathy, a leading cause of vision loss in working-age population, is often associated with inflammation and apoptosis. We have previously reported that sitagliptin, a DPP-IV inhibitor, exerts beneficial effects in the retina of type 2 diabetic animals. The present study aimed to evaluate whether sitagliptin can exert protective effects in the retina of type 1 diabetic animals by a mechanism independent of insulin secretion and glycemia normalization. Streptozotocin-induced diabetic rats were treated orally with sitagliptin (5mg/kg/day) for the last two weeks of 4 weeks of diabetes. Sitagliptin treatment did not change the weight and glucose, HbA1c or insulin levels. However, it prevented the diabetes-induced increase in DPP-IV/CD26 activity and levels in serum and retina. Sitagliptin also prevented the increase in blood-retinal barrier (BRB) permeability and inhibited the changes in immunoreactivity and endothelial subcellular distribution of occludin, claudin-5 and ZO-1 proteins induced by diabetes. Furthermore, sitagliptin decreased the retinal inflammatory state and neuronal apoptosis. Sitagliptin inhibited the BRB breakdown in a type 1 diabetic animal model, by a mechanism independent of normalization of glycemia, by preventing changes in tight junctions (TJs) organization. Sitagliptin also exerted protective effects against inflammation and pro-apoptotic state in the retina of diabetic rats. Altogether, these results suggest that sitagliptin might be envisaged to be used to prevent or delay some of the alterations associated with the development of diabetic retinopathy.
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Affiliation(s)
- Andreia Gonçalves
- Laboratory of Pharmacology and Experimental Therapeutics, IBILI - Institute for Biomedical Imaging and Life Sciences, Faculty of Medicine, University of Coimbra, Portugal
| | - Catarina Marques
- Laboratory of Pharmacology and Experimental Therapeutics, IBILI - Institute for Biomedical Imaging and Life Sciences, Faculty of Medicine, University of Coimbra, Portugal
| | - Ermelindo Leal
- Centre for Neuroscience and Cell Biology, University of Coimbra, Portugal
| | - Carlos F Ribeiro
- Laboratory of Pharmacology and Experimental Therapeutics, IBILI - Institute for Biomedical Imaging and Life Sciences, Faculty of Medicine, University of Coimbra, Portugal
| | - Flávio Reis
- Laboratory of Pharmacology and Experimental Therapeutics, IBILI - Institute for Biomedical Imaging and Life Sciences, Faculty of Medicine, University of Coimbra, Portugal
| | - António F Ambrósio
- Centre of Ophthalmology and Vision Sciences, IBILI, Faculty of Medicine, University of Coimbra, Portugal; AIBILI, University of Coimbra, Portugal
| | - Rosa Fernandes
- Laboratory of Pharmacology and Experimental Therapeutics, IBILI - Institute for Biomedical Imaging and Life Sciences, Faculty of Medicine, University of Coimbra, Portugal.
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Sakamoto K, Kuroki T, Okuno Y, Sekiya H, Watanabe A, Sagawa T, Ito H, Mizuta A, Mori A, Nakahara T, Ishii K. Activation of the TRPV1 channel attenuates N-methyl-D-aspartic acid-induced neuronal injury in the rat retina. Eur J Pharmacol 2014; 733:13-22. [PMID: 24704373 DOI: 10.1016/j.ejphar.2014.03.035] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2013] [Revised: 03/04/2014] [Accepted: 03/13/2014] [Indexed: 12/21/2022]
Abstract
Capsaicin, a transient receptor potential vanilloid type1 (TRPV1) agonist, has been reported to protect against ischemia-reperfusion injury in various organs, including the brain, heart, and kidney, whereas activation of TRPV1 was also reported to contribute to neurodegeneration, including pressure-induced retinal ganglion cell death in vitro. We histologically investigated the effects of capsaicin and SA13353, TRPV1 agonists, on retinal injury induced by intravitreal N-methyl-d-aspartic acid (NMDA; 200 nmol/eye) in rats in vivo. Under ketamine/xylazine anesthesia, male Sprague-Dawley rats were subjected to intravitreal NMDA injection. Capsaicin (5.0 nmol/eye) was intravitreally admianeously with NMDA injection. SA13353 (10mg/kg) was intraperitoneally administered 15 min before NMDA injection. Morphometric evaluation at 7 days after NMDA injection showed that intravitreal NMDA injection resulted in ganglion cell loss. Capsaicin and SA13353 almost completely prevented this damage. Treatment with capsazepine (TRPV1 antagonist, 0.5 nmol/eye), CGRP (8-37) (calcitonin gene-related peptide (CGRP) receptor antagonist, 0.5 pmol/eye), or RP67580 (tachykinin NK1 receptor antagonist, 0.5 nmol/eye) almost completely negated the protective effect of capsaicin in the NMDA-injected rats. Seven days after intravitreal NMDA injection, the cell number of retinal ganglion cell was significantly smaller than in the eye that had received capsaicin in B6.Cg-TgN(Thy1-CFP)23Jrs/J transgenic mice that express the enhanced cyan fluorescent protein in retinal ganglion cells in the retina. These results suggested that activation of TRPV1 protects retinal neurons from the injury induced by intravitreal NMDA in rats in vivo. Activation of CGRP and tachykinin NK1 receptors is possibly involved in underlying protective mechanisms.
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Affiliation(s)
- Kenji Sakamoto
- Department of Molecular Pharmacology, Kitasato University School of Pharmaceutical Sciences, 9-1 Shirokane 5-chome, Minato-ku, Tokyo 108-8641, Japan.
| | - Taiyo Kuroki
- Department of Molecular Pharmacology, Kitasato University School of Pharmaceutical Sciences, 9-1 Shirokane 5-chome, Minato-ku, Tokyo 108-8641, Japan
| | - Yui Okuno
- Department of Molecular Pharmacology, Kitasato University School of Pharmaceutical Sciences, 9-1 Shirokane 5-chome, Minato-ku, Tokyo 108-8641, Japan
| | - Haruna Sekiya
- Department of Molecular Pharmacology, Kitasato University School of Pharmaceutical Sciences, 9-1 Shirokane 5-chome, Minato-ku, Tokyo 108-8641, Japan
| | - Akihiro Watanabe
- Department of Molecular Pharmacology, Kitasato University School of Pharmaceutical Sciences, 9-1 Shirokane 5-chome, Minato-ku, Tokyo 108-8641, Japan
| | - Tomonori Sagawa
- Department of Molecular Pharmacology, Kitasato University School of Pharmaceutical Sciences, 9-1 Shirokane 5-chome, Minato-ku, Tokyo 108-8641, Japan
| | - Hiroko Ito
- Department of Molecular Pharmacology, Kitasato University School of Pharmaceutical Sciences, 9-1 Shirokane 5-chome, Minato-ku, Tokyo 108-8641, Japan
| | - Aya Mizuta
- Department of Molecular Pharmacology, Kitasato University School of Pharmaceutical Sciences, 9-1 Shirokane 5-chome, Minato-ku, Tokyo 108-8641, Japan
| | - Asami Mori
- Department of Molecular Pharmacology, Kitasato University School of Pharmaceutical Sciences, 9-1 Shirokane 5-chome, Minato-ku, Tokyo 108-8641, Japan
| | - Tsutomu Nakahara
- Department of Molecular Pharmacology, Kitasato University School of Pharmaceutical Sciences, 9-1 Shirokane 5-chome, Minato-ku, Tokyo 108-8641, Japan
| | - Kunio Ishii
- Department of Molecular Pharmacology, Kitasato University School of Pharmaceutical Sciences, 9-1 Shirokane 5-chome, Minato-ku, Tokyo 108-8641, Japan
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Leonelli M, Martins DO, Britto LRG. Retinal Cell Death Induced by TRPV1 Activation Involves NMDA Signaling and Upregulation of Nitric Oxide Synthases. Cell Mol Neurobiol 2013; 33:379-92. [DOI: 10.1007/s10571-012-9904-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2012] [Accepted: 12/29/2012] [Indexed: 01/23/2023]
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16
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Mergler S, Cheng Y, Skosyrski S, Garreis F, Pietrzak P, Kociok N, Dwarakanath A, Reinach PS, Kakkassery V. Altered calcium regulation by thermosensitive transient receptor potential channels in etoposide-resistant WERI-Rb1 retinoblastoma cells. Exp Eye Res 2012; 94:157-73. [DOI: 10.1016/j.exer.2011.12.002] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2011] [Revised: 11/04/2011] [Accepted: 12/03/2011] [Indexed: 10/14/2022]
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17
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Thermo-sensitive transient receptor potential vanilloid channel-1 regulates intracellular calcium and triggers chromogranin A secretion in pancreatic neuroendocrine BON-1 tumor cells. Cell Signal 2012; 24:233-46. [DOI: 10.1016/j.cellsig.2011.09.005] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2011] [Accepted: 09/05/2011] [Indexed: 11/18/2022]
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18
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Janes K, Neumann WL, Salvemini D. Anti-superoxide and anti-peroxynitrite strategies in pain suppression. Biochim Biophys Acta Mol Basis Dis 2011; 1822:815-21. [PMID: 22200449 DOI: 10.1016/j.bbadis.2011.12.008] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2011] [Revised: 12/05/2011] [Accepted: 12/06/2011] [Indexed: 02/08/2023]
Abstract
Superoxide (SO, O(2)·(-)) and its reaction product peroxynitrite (PN, ONOO(-)) have been shown to be important in the development of pain of several etiologies. While significant progress has been made in teasing out the relative contribution of SO and PN peripherally, spinally, and supraspinally during the development and maintenance of central sensitization and pain, there is still a considerable void in our understanding. Further research is required in order to develop improved therapeutic strategies for selectively eliminating SO and/or PN. Furthermore, it may be that PN is a more attractive target, in that unlike SO it has no currently known beneficial role. Our group has been at the forefront of research concerning the role of SO and PN in pain, and our current findings have led to the development of two new classes of orally active catalysts which are selective for PN decomposition while sparing SO. This article is part of a Special Issue entitled: Antioxidants and Antioxidant Treatment in Disease.
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Affiliation(s)
- Kali Janes
- Department of Pharmacological and Physiological Science, Saint Louis University School of Medicine, 1402 South Grand Boulevard, St. Louis, MO 63104, USA
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19
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Leonelli M, Graciano M, Britto L. TRP channels, omega-3 fatty acids, and oxidative stress in neurodegeneration: from the cell membrane to intracellular cross-links. Braz J Med Biol Res 2011; 44:1088-96. [DOI: 10.1590/s0100-879x2011007500124] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
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Salvemini D, Little JW, Doyle T, Neumann WL. Roles of reactive oxygen and nitrogen species in pain. Free Radic Biol Med 2011; 51:951-66. [PMID: 21277369 PMCID: PMC3134634 DOI: 10.1016/j.freeradbiomed.2011.01.026] [Citation(s) in RCA: 222] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/12/2010] [Revised: 01/19/2011] [Accepted: 01/20/2011] [Indexed: 02/07/2023]
Abstract
Peroxynitrite (PN; ONOO⁻) and its reactive oxygen precursor superoxide (SO; O₂•⁻) are critically important in the development of pain of several etiologies including pain associated with chronic use of opiates such as morphine (also known as opiate-induced hyperalgesia and antinociceptive tolerance). This is now an emerging field in which considerable progress has been made in terms of understanding the relative contributions of SO, PN, and nitroxidative stress in pain signaling at the molecular and biochemical levels. Aggressive research in this area is poised to provide the pharmacological basis for development of novel nonnarcotic analgesics that are based upon the unique ability to selectively eliminate SO and/or PN. As we have a better understanding of the roles of SO and PN in pathophysiological settings, targeting PN may be a better therapeutic strategy than targeting SO. This is because, unlike PN, which has no currently known beneficial role, SO may play a significant role in learning and memory. Thus, the best approach may be to spare SO while directly targeting its downstream product, PN. Over the past 15 years, our team has spearheaded research concerning the roles of SO and PN in pain and these results are currently leading to the development of solid therapeutic strategies in this important area.
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Affiliation(s)
- Daniela Salvemini
- Department of Pharmacological and Physiological Science, Saint Louis University School of Medicine, St. Louis, MO 63104, USA.
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21
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TRPV1 receptors modulate retinal development. Int J Dev Neurosci 2011; 29:405-13. [PMID: 21414401 DOI: 10.1016/j.ijdevneu.2011.03.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2010] [Revised: 01/19/2011] [Accepted: 03/08/2011] [Indexed: 12/11/2022] Open
Abstract
We investigated the possible participation of TRPV1 channels in retinal apoptosis and overall development. Retinas from newborn, male albino rats were treated in vitro with capsazepine, a TRPV1 antagonist. The expression of cell cycle markers was not changed after TRPV1 blockade, whereas capsazepine reduced the number of apoptotic cells throughout the retina,increased ERK1/2 and p38 phosphorylation and slightly reduced JNK phosphorylation. The expression of BAD, Bcl-2, as well as integral and cleaved capsase-3 were similar in all experimental conditions. Newborn rats were kept for 2 months after receiving high doses of capsazepine. In their retinas, calbindin and parvalbumin protein levels were upregulated, but only the number of amacrine-like, parvalbumin-positive cells was increased. The numbers of calretinin, calbindin, ChAT, vimentin, PKC-alpha and GABA-positive cells were similar in both conditions. Protein expression of synapsin Ib was also increased in the retinas of capsazepine-treated rats. Calretinin, vimentin, GFAP, synapsin Ia, synaptophysin and light neurofilament protein levels were not changed when compared to control values. Our results indicate that TRPV1 channels play a role in the control of the early apoptosis that occur during retinal development, which might be dependent on MAPK signaling. Moreover, it seems that TRPV1 function might be important for neuronal and synaptic maturation in the retina.
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