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Chamorro-Aguirre E, Gaveglio VL, Pascual AC, Pasquaré SJ. The Metabolism of 2-arachidonoylglycerol in Rod Outer Segments Is Modulated by Proteins Involved in the Phototransduction Process. Mol Neurobiol 2024; 61:4577-4588. [PMID: 38109005 DOI: 10.1007/s12035-023-03873-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Accepted: 12/11/2023] [Indexed: 12/19/2023]
Abstract
We previously reported that 2-arachidonoylglycerol (2-AG) synthesis by diacylglycerol lipase (DAGL) and lysophosphatidate phosphohydrolase (LPAP) and hydrolysis by monoacylglycerol lipase (MAGL) in rod outer segments (ROS) from bovine retina were differently modified by light applied to the retina. Based on these findings, the aim of the present research was to evaluate whether 2-AG metabolism could be modulated by proteins involved in the visual process. To this end, ROS kept in darkness (DROS) or obtained in darkness and then subjected to light (BROS) were treated with GTPγS and GDPβS, or with low and moderate ionic strength buffers for detaching soluble and peripheral proteins, or soluble proteins, respectively. Only DAGL activity was stimulated by the application of light to the ROS. GTPγS-stimulated DAGL activity in DROS reached similar values to that observed in BROS. The studies using different ionic strength show that (1) the highest decrease in DROS DAGL activity was observed when both phosphodiesterase (PDE) and transducin α (Tα) are totally membrane-associated; (2) the decrease in BROS DAGL activity does not depend on PDE association to membrane, and that (3) MAGL activity decreases, both in DROS and BROS, when PDE is not associated to the membrane. Our results indicate that the bioavailability of 2-AG under light conditions is favored by G protein-stimulated increase in DAGL activity and hindered principally by Tα/PDE association with the ROS membrane, which decreases DAGL activity.
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Affiliation(s)
- Estefanía Chamorro-Aguirre
- Instituto de Investigaciones Bioquímicas de Bahía Blanca (INIBIBB, UNS-CONICET), Edificio E1, Camino La Carrindanga Km 7, 8000, Bahía Blanca, Argentina
| | - Virginia L Gaveglio
- Instituto de Investigaciones Bioquímicas de Bahía Blanca (INIBIBB, UNS-CONICET), Edificio E1, Camino La Carrindanga Km 7, 8000, Bahía Blanca, Argentina
- Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur, San Juan 670, 8000, Bahía Blanca, Argentina
| | - Ana C Pascual
- Instituto de Investigaciones Bioquímicas de Bahía Blanca (INIBIBB, UNS-CONICET), Edificio E1, Camino La Carrindanga Km 7, 8000, Bahía Blanca, Argentina
- Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur, San Juan 670, 8000, Bahía Blanca, Argentina
| | - Susana J Pasquaré
- Instituto de Investigaciones Bioquímicas de Bahía Blanca (INIBIBB, UNS-CONICET), Edificio E1, Camino La Carrindanga Km 7, 8000, Bahía Blanca, Argentina.
- Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur, San Juan 670, 8000, Bahía Blanca, Argentina.
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Papadogkonaki S, Spyridakos D, Lapokonstantaki E, Chaniotakis N, Makriyannis A, Malamas MS, Thermos K. Investigating the Effects of Exogenous and Endogenous 2-Arachidonoylglycerol on Retinal CB1 Cannabinoid Receptors and Reactive Microglia in Naive and Diseased Retina. Int J Mol Sci 2023; 24:15689. [PMID: 37958673 PMCID: PMC10650178 DOI: 10.3390/ijms242115689] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Revised: 10/22/2023] [Accepted: 10/26/2023] [Indexed: 11/15/2023] Open
Abstract
The endocannabinoid system (ECS) is a new target for the development of retinal disease therapeutics, whose pathophysiology involves neurodegeneration and neuroinflammation. The endocannabinoid 2-arachidonoylglycerol (2-AG) affects neurons and microglia by activating CB1/CB2 cannabinoid receptors (Rs). The aim of this study was to investigate the effects of 2-AG on the CB1R expression/downregulation and retinal neurons/reactive microglia, when administered repeatedly (4 d), in three different paradigms. These involved the 2-AG exogenous administration (a) intraperitoneally (i.p.) and (b) topically and (c) by enhancing the 2-AG endogenous levels via the inhibition (AM11920, i.p.) of its metabolic enzymes (MAGL/ABHD6). Sprague Dawley rats were treated as mentioned above in the presence or absence of CB1/CB2R antagonists and the excitatory amino acid, α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA). Immunohistochemistry, Western blot and a 2-AG level analyses were performed. The 2-AG repeated treatment (i.p.) induced the CB1R downregulation, abolishing its neuroprotective actions. However, 2-AG attenuated the AMPA-induced activation of microglia via the CB2R, as concurred by the AM630 antagonist effect. Topically administered 2-AG was efficacious as a neuroprotectant/antiapoptotic and anti-inflammatory agent. AM11920 increased the 2-AG levels providing neuroprotection against excitotoxicity and reduced microglial activation without affecting the CB1R expression. Our findings show that 2-AG, in the three paradigms studied, displays differential pharmacological profiles in terms of the downregulation of the CB1R and neuroprotection. All treatments, however, attenuated the activation of microglia via the CB2R activation, supporting the anti-inflammatory role of 2-AG in the retina.
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Affiliation(s)
- Sofia Papadogkonaki
- Department of Pharmacology, School of Medicine, University of Crete, Heraklion, 71003 Crete, Greece; (S.P.); (D.S.)
| | - Dimitris Spyridakos
- Department of Pharmacology, School of Medicine, University of Crete, Heraklion, 71003 Crete, Greece; (S.P.); (D.S.)
| | | | - Nikos Chaniotakis
- Department of Chemistry, University of Crete, Heraklion, 71003 Crete, Greece; (E.L.); (N.C.)
| | - Alexandros Makriyannis
- Center for Drug Discovery and Departments of Chemistry and Chemical Biology and Pharmaceutical Sciences, Northeastern University, Boston, MA 02115, USA; (A.M.); (M.S.M.)
| | - Michael S. Malamas
- Center for Drug Discovery and Departments of Chemistry and Chemical Biology and Pharmaceutical Sciences, Northeastern University, Boston, MA 02115, USA; (A.M.); (M.S.M.)
| | - Kyriaki Thermos
- Department of Pharmacology, School of Medicine, University of Crete, Heraklion, 71003 Crete, Greece; (S.P.); (D.S.)
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Wei J, Zhang L, Wu K, Yu J, Gao F, Cheng J, Zhang T, Zhou X, Zong Y, Huang X, Jiang C. R-(+)-WIN55212-2 protects pericytes from ischemic damage and restores retinal microcirculatory patency after ischemia/reperfusion injury. Biomed Pharmacother 2023; 166:115197. [PMID: 37572634 DOI: 10.1016/j.biopha.2023.115197] [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: 04/14/2023] [Revised: 07/09/2023] [Accepted: 07/18/2023] [Indexed: 08/14/2023] Open
Abstract
BACKGROUND AND PURPOSE Cannabinoids are vasoactive substances that act as key regulators of arterial tone in the blood vessels supplying peripheral tissues and the central nervous system. This study aimed to investigate the potential of R-(+)-WIN55212-2 (WIN), a cannabinoid receptor 1 agonist (CB1), as a treatment for retinal ischemia/reperfusion (I/R) injury. EXPERIMENTAL APPROACH Male Wistar rats were subjected to retinal I/R injury by increasing intraocular pressure in the anterior chamber. The rats were randomly divided into four groups: normal control, I/R, vehicle (pre-treated with dimethyl sulfoxide [DMSO] via intraperitoneal injection), and experimental (pre-treated with WIN at a dose of 1 ml/kg via intraperitoneal injection). The rats were sacrificed at different time points of reperfusion (1 hour, 3 hours, 6 hours, and 1 day) after inducing retinal I/R injury, and their retinas were collected for analysis. Oxygen-glucose deprived/reperfusion (OGD/R) was performed by initially perfusing the retinas with oxygenated artificial cerebrospinal fluid (ACSF), then switching to an OGD solution to simulate ischemia, followed by another perfusion with ACSF. Pericyte contraction and the "no-reflow" phenomenon were observed using infrared differential interference contrast (IR-DIC) microscopy and immunohistochemistry. Western blot, enzyme-linked immunosorbent assay (ELISA), and nitric oxide (NO) detection were used to explore the potential mechanism. KEY RESULTS In both the OGD/R and I/R models, retinal pericytes exhibited persistent contraction even after reperfusion. The ability of WIN to regulate the tone of retinal pericytes and capillaries was specifically blocked by the BKCa inhibitor iberiotoxin (100 nM). WIN demonstrated a protective effect against retinal I/R injury by preserving blood flow in vessels containing pericytes. Pretreatment with WIN alleviated the persistent contraction and apoptosis of retinal pericytes in I/R-induced rats, accompanied by a reduction in intracellular calcium ion (Ca2+) concentration. The expression of CB1 decreased in a time-dependent manner in the I/R group. After I/R injury, endothelium-derived nitric oxide (eNOS) levels were reduced at all time points, which was successfully reversed by WIN therapy except for the 1 day group. Additionally, the downregulation of cyclic guanosine monophosphate (cGMP) and BKCa expression at 3 hours, 6 hours, and 1 day after I/R injury was restored by pretreatment of WIN. CONCLUSIONS & IMPLICATIONS WIN exerted its protective effects on retinal I/R injury by inhibiting the contraction and apoptosis of pericytes through the CB1-eNOS-cGMP-BKCa signaling pathway, thus ameliorated the occlusion of retinal capillaries.
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Affiliation(s)
- Jiaojiao Wei
- Department of Ophthalmology and Vision Science, Eye and ENT Hospital, Fudan University, Shanghai 200031, People's Republic of China; Eye and ENT Hospital, State Key laboratory of Medical Neurobiology, Institutes of Brain Science and Collaborative Innovation Center for Brain Science, Fudan University, Shanghai 200031, People's Republic of China; Key Laboratory of Myopia of State Health Ministry, and Key Laboratory of Visual Impairment and Restoration of Shanghai, Shanghai 200031, People's Republic of China
| | - Lili Zhang
- Department of Ophthalmology and Vision Science, Eye and ENT Hospital, Fudan University, Shanghai 200031, People's Republic of China; Eye and ENT Hospital, State Key laboratory of Medical Neurobiology, Institutes of Brain Science and Collaborative Innovation Center for Brain Science, Fudan University, Shanghai 200031, People's Republic of China; Key Laboratory of Myopia of State Health Ministry, and Key Laboratory of Visual Impairment and Restoration of Shanghai, Shanghai 200031, People's Republic of China
| | - Kaicheng Wu
- Department of Ophthalmology and Vision Science, Eye and ENT Hospital, Fudan University, Shanghai 200031, People's Republic of China; Eye and ENT Hospital, State Key laboratory of Medical Neurobiology, Institutes of Brain Science and Collaborative Innovation Center for Brain Science, Fudan University, Shanghai 200031, People's Republic of China; Key Laboratory of Myopia of State Health Ministry, and Key Laboratory of Visual Impairment and Restoration of Shanghai, Shanghai 200031, People's Republic of China
| | - Jian Yu
- Department of Ophthalmology and Vision Science, Eye and ENT Hospital, Fudan University, Shanghai 200031, People's Republic of China; Eye and ENT Hospital, State Key laboratory of Medical Neurobiology, Institutes of Brain Science and Collaborative Innovation Center for Brain Science, Fudan University, Shanghai 200031, People's Republic of China; Key Laboratory of Myopia of State Health Ministry, and Key Laboratory of Visual Impairment and Restoration of Shanghai, Shanghai 200031, People's Republic of China
| | - Fengjuan Gao
- Department of Ophthalmology and Vision Science, Eye and ENT Hospital, Fudan University, Shanghai 200031, People's Republic of China; Eye and ENT Hospital, State Key laboratory of Medical Neurobiology, Institutes of Brain Science and Collaborative Innovation Center for Brain Science, Fudan University, Shanghai 200031, People's Republic of China; Key Laboratory of Myopia of State Health Ministry, and Key Laboratory of Visual Impairment and Restoration of Shanghai, Shanghai 200031, People's Republic of China
| | - Jingyi Cheng
- Department of Ophthalmology and Vision Science, Eye and ENT Hospital, Fudan University, Shanghai 200031, People's Republic of China; Eye and ENT Hospital, State Key laboratory of Medical Neurobiology, Institutes of Brain Science and Collaborative Innovation Center for Brain Science, Fudan University, Shanghai 200031, People's Republic of China; Key Laboratory of Myopia of State Health Ministry, and Key Laboratory of Visual Impairment and Restoration of Shanghai, Shanghai 200031, People's Republic of China
| | - Ting Zhang
- Department of Ophthalmology and Vision Science, Eye and ENT Hospital, Fudan University, Shanghai 200031, People's Republic of China; Eye and ENT Hospital, State Key laboratory of Medical Neurobiology, Institutes of Brain Science and Collaborative Innovation Center for Brain Science, Fudan University, Shanghai 200031, People's Republic of China; Key Laboratory of Myopia of State Health Ministry, and Key Laboratory of Visual Impairment and Restoration of Shanghai, Shanghai 200031, People's Republic of China
| | - Xujiao Zhou
- Eye and ENT Hospital, State Key laboratory of Medical Neurobiology, Institutes of Brain Science and Collaborative Innovation Center for Brain Science, Fudan University, Shanghai 200031, People's Republic of China; Key Laboratory of Myopia of State Health Ministry, and Key Laboratory of Visual Impairment and Restoration of Shanghai, Shanghai 200031, People's Republic of China.
| | - Yuan Zong
- Department of Ophthalmology and Vision Science, Eye and ENT Hospital, Fudan University, Shanghai 200031, People's Republic of China; Eye and ENT Hospital, State Key laboratory of Medical Neurobiology, Institutes of Brain Science and Collaborative Innovation Center for Brain Science, Fudan University, Shanghai 200031, People's Republic of China; Key Laboratory of Myopia of State Health Ministry, and Key Laboratory of Visual Impairment and Restoration of Shanghai, Shanghai 200031, People's Republic of China.
| | - Xiaojing Huang
- Department of Ophthalmology, Shanghai Pudong New Area Gongli Hospital, Shanghai 200135, People's Republic of China.
| | - Chunhui Jiang
- Department of Ophthalmology and Vision Science, Eye and ENT Hospital, Fudan University, Shanghai 200031, People's Republic of China; Eye and ENT Hospital, State Key laboratory of Medical Neurobiology, Institutes of Brain Science and Collaborative Innovation Center for Brain Science, Fudan University, Shanghai 200031, People's Republic of China; Key Laboratory of Myopia of State Health Ministry, and Key Laboratory of Visual Impairment and Restoration of Shanghai, Shanghai 200031, People's Republic of 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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5
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Wu JH, Radha Saseendrakumar B, Moghimi S, Sidhu S, Kamalipour A, Weinreb RN, Baxter SL. Epidemiology and factors associated with cannabis use among patients with glaucoma in the All of Us Research Program. Heliyon 2023; 9:e15811. [PMID: 37215923 PMCID: PMC10192773 DOI: 10.1016/j.heliyon.2023.e15811] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Revised: 04/09/2023] [Accepted: 04/21/2023] [Indexed: 05/24/2023] Open
Abstract
Purpose To examine the epidemiology and factors of cannabis use among open-angle glaucoma (OAG) patients. Methods In this cross-sectional study, OAG participants in the All of Us database were included. Cannabis ever-users were defined based on record of cannabis use. Demographic and socioeconomic data were collected and compared between cannabis ever-users and never-users using Chi-Square tests and logistic regression. Odds ratios (OR) of potential factors associated with cannabis use were examined in univariable and multivariable models. Results Among 3723 OAG participants, 1436 (39%) were cannabis ever-users. The mean (SD) age of never-users and ever-users was 72.9 (10.4) and 69.2 (9.6) years, respectively (P < 0.001). Compared to never-users, Black (34%) and male (55%) participants were better represented in ever-users, while Hispanic or Latino participants (6%) were less represented (P < 0.001). Diversity was also observed in socioeconomic characteristics including marital status, housing security, and income/education levels. A higher percentage of ever-users had a degree ≥12 grades (91%), salaried employment (26%), housing insecurity (12%), and history of cigar smoking (48%), alcohol consumption (96%), and other substance use (47%) (P < 0.001). In the multivariable analysis, Black race (OR [95% CI] = 1.33 [1.06, 1.68]), higher education (OR = 1.19 [1.07, 1.32]), and history of nicotine product smoking (OR: 2.04-2.83), other substance use (OR = 8.14 [6.63, 10.04]), and alcohol consumption (OR = 6.80 [4.45, 10.79]) were significant factors associated with cannabis use. Increased age (OR = 0.96 [0.95, 0.97]), Asian race (OR = 0.18 [0.09, 0.33]), and Hispanic/Latino ethnicity (OR = 0.43 [0.27, 0.68]) were associated with decreased odds of use (P < 0.02). Conclusions This study elucidated the previously uncharacterized epidemiology and factors associated with cannabis use among OAG patients, which may help to identify patients requiring additional outreach on unsupervised marijuana use.
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Affiliation(s)
- Jo-Hsuan Wu
- Viterbi Family Department of Ophthalmology and Shiley Eye Institute, University of California San Diego, La Jolla, CA, USA
| | - Bharanidharan Radha Saseendrakumar
- Viterbi Family Department of Ophthalmology and Shiley Eye Institute, University of California San Diego, La Jolla, CA, USA
- UCSD Health Department of Biomedical Informatics, University of California San Diego, La Jolla, CA, USA
| | - Sasan Moghimi
- Viterbi Family Department of Ophthalmology and Shiley Eye Institute, University of California San Diego, La Jolla, CA, USA
| | - Sophia Sidhu
- Viterbi Family Department of Ophthalmology and Shiley Eye Institute, University of California San Diego, La Jolla, CA, USA
| | - Alireza Kamalipour
- Viterbi Family Department of Ophthalmology and Shiley Eye Institute, University of California San Diego, La Jolla, CA, USA
| | - Robert N. Weinreb
- Viterbi Family Department of Ophthalmology and Shiley Eye Institute, University of California San Diego, La Jolla, CA, USA
| | - Sally L. Baxter
- Viterbi Family Department of Ophthalmology and Shiley Eye Institute, University of California San Diego, La Jolla, CA, USA
- UCSD Health Department of Biomedical Informatics, University of California San Diego, La Jolla, CA, USA
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Saraiva SM, Martín-Banderas L, Durán-Lobato M. Cannabinoid-Based Ocular Therapies and Formulations. Pharmaceutics 2023; 15:pharmaceutics15041077. [PMID: 37111563 PMCID: PMC10146987 DOI: 10.3390/pharmaceutics15041077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 03/20/2023] [Accepted: 03/22/2023] [Indexed: 03/30/2023] Open
Abstract
The interest in the pharmacological applications of cannabinoids is largely increasing in a wide range of medical areas. Recently, research on its potential role in eye conditions, many of which are chronic and/or disabling and in need of new alternative treatments, has intensified. However, due to cannabinoids’ unfavorable physicochemical properties and adverse systemic effects, along with ocular biological barriers to local drug administration, drug delivery systems are needed. Hence, this review focused on the following: (i) identifying eye disease conditions potentially subject to treatment with cannabinoids and their pharmacological role, with emphasis on glaucoma, uveitis, diabetic retinopathy, keratitis and the prevention of Pseudomonas aeruginosa infections; (ii) reviewing the physicochemical properties of formulations that must be controlled and/or optimized for successful ocular administration; (iii) analyzing works evaluating cannabinoid-based formulations for ocular administration, with emphasis on results and limitations; and (iv) identifying alternative cannabinoid-based formulations that could potentially be useful for ocular administration strategies. Finally, an overview of the current advances and limitations in the field, the technological challenges to overcome and the prospective further developments, is provided.
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Affiliation(s)
- Sofia M. Saraiva
- CPIRN-IPG—Center of Potential and Innovation of Natural Resources, Polytechnic Institute of Guarda, Av. Dr. Francisco de Sá Carneiro, No. 50, 6300-559 Guarda, Portugal
| | - Lucía Martín-Banderas
- Departamento Farmacia y Tecnología Farmacéutica, Facultad de Farmacia, Universidad de Sevilla, C/Prof. García González n °2, 41012 Sevilla, Spain;
- Instituto de Biomedicina de Sevilla (IBIS), Campus Hospital Universitario Virgen del Rocío, 41013 Sevilla, Spain
- Correspondence: ; Tel.: +34-954556754
| | - Matilde Durán-Lobato
- Departamento Farmacia y Tecnología Farmacéutica, Facultad de Farmacia, Universidad de Sevilla, C/Prof. García González n °2, 41012 Sevilla, Spain;
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7
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Chetoni P, Burgalassi S, Zucchetti E, Granchi C, Minutolo F, Tampucci S, Monti D. MAGL inhibitor NanoMicellar formulation (MAGL-NanoMicellar) for the development of an antiglaucoma eye drop. Int J Pharm 2022; 625:122078. [PMID: 35932931 DOI: 10.1016/j.ijpharm.2022.122078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Revised: 07/04/2022] [Accepted: 08/01/2022] [Indexed: 11/15/2022]
Abstract
The ocular endocannabinoid system (ECS) including enzymes and CB1/CB2 receptors determines various substantial effects, such as anti-inflammatory activity and reduction of the intraocular pressure (IOP). The modulation of 2-arachidonoylglycerol (2-AG) levels obtained via MAGL inhibition is considered as a promising pharmacological strategy to activate the ECS. Within the scope of this study, the effect of a selective monoacylglycerol lipase (MAGL) inhibitor (MAGL17b) was investigated by measuring the IOP reduction in normotensive rabbits after performing a solubilisation process of the molecule with non-ionic surfactants, to produce suitable eye drops containing the highest possible concentration of the drug. Furthermore, the study involved the evaluation of cytotoxicity and of in vitro/ex vivo corneal permeation of MAG17b of selected formulations based on polyoxyl(35)castor oil (C-EL) and polyethylene glycol (80) sorbitan monolaurate (TW80). The solubilisation of 0.5 mM MAGL17b with 3% w/w TW80 (TW80/3-17b), through the formation of NanoMicellar structures (diameter of 12.3 nm), determined a significant permeation of MAGL17b, both through excised rabbits corneas and reconstituted corneal epithelium, with a limited corneal epithelial cells death. The blockade of MAGL activity induced a IOP reduction up to 4 mmHg in albino and pigmented rabbits after topical instillation, thus confirming the potential efficacy of the MAGL inhibition approach in the treatment of ocular pathologies.
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Affiliation(s)
- Patrizia Chetoni
- Department of Pharmacy, University of Pisa, Pisa, Italy; Inter-University Center for the Promotion of the 3Rs Principles in Teaching & Research (Centro 3R), Pisa, Italy
| | - Susi Burgalassi
- Department of Pharmacy, University of Pisa, Pisa, Italy; Inter-University Center for the Promotion of the 3Rs Principles in Teaching & Research (Centro 3R), Pisa, Italy
| | | | | | | | - Silvia Tampucci
- Department of Pharmacy, University of Pisa, Pisa, Italy; Inter-University Center for the Promotion of the 3Rs Principles in Teaching & Research (Centro 3R), Pisa, Italy
| | - Daniela Monti
- Department of Pharmacy, University of Pisa, Pisa, Italy; Inter-University Center for the Promotion of the 3Rs Principles in Teaching & Research (Centro 3R), Pisa, Italy
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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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Neuroprotection of Retinal Ganglion Cells In Vivo Using the Activation of the Endogenous Cannabinoid Signaling System in Mammalian Eyes. Neuronal Signal 2022; 6:NS20210038. [PMID: 35233292 PMCID: PMC8850705 DOI: 10.1042/ns20210038] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Revised: 01/13/2022] [Accepted: 01/18/2022] [Indexed: 12/02/2022] Open
Abstract
Cannabinoid and glutamatergic signaling systems in the human retina coexist and greatly influence one another. Under glaucomatous conditions, excess levels of glutamate accrete in the retinal ganglion cell (RGC) layer. The present study tests the putative neuroprotective effect mediated by cannabinoids at the CB1 and CB2 receptors. In the first experiment, mice were given intravitreal injections of 160 nmol N-methyl-d-aspartic acid (NMDA) in one eye and saline in the paired eye. In the second experiment, both eyes were given NMDA, while one of the two was additionally given the cannabinoid agonist WIN 55,212-2. Ten days later, animals were perfused and the retinae were dissected as wholemounts and stained with Cresyl Violet. Quantitative analysis revealed that 70% of the neurons in the retinal ganglion cell (RGC) layer exposed to NMDA underwent cell death. The addition of the cannabinoid CB1/CB2 agonist doubled the number of neurons surviving the NMDA treatment. These data provide evidence that cannabinoids, either exogenous or endogenous, may be harnessed to provide protection from neurodegenerative diseases, including glaucoma, and from glutamate-induced, and potentially other forms of neurotoxicity, under chronic or acute conditions.
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10
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Treatment of Glaucoma with Natural Products and Their Mechanism of Action: An Update. Nutrients 2022; 14:nu14030534. [PMID: 35276895 PMCID: PMC8840399 DOI: 10.3390/nu14030534] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Revised: 01/15/2022] [Accepted: 01/18/2022] [Indexed: 02/07/2023] Open
Abstract
Glaucoma is one of the leading causes of irreversible blindness. It is generally caused by increased intraocular pressure, which results in damage of the optic nerve and retinal ganglion cells, ultimately leading to visual field dysfunction. However, even with the use of intraocular pressure-lowering eye drops, the disease still progresses in some patients. In addition to mechanical and vascular dysfunctions of the eye, oxidative stress, neuroinflammation and excitotoxicity have also been implicated in the pathogenesis of glaucoma. Hence, the use of natural products with antioxidant and anti-inflammatory properties may represent an alternative approach for glaucoma treatment. The present review highlights recent preclinical and clinical studies on various natural products shown to possess neuroprotective properties for retinal ganglion cells, which thereby may be effective in the treatment of glaucoma. Intraocular pressure can be reduced by baicalein, forskolin, marijuana, ginsenoside, resveratrol and hesperidin. Alternatively, Ginkgo biloba, Lycium barbarum, Diospyros kaki, Tripterygium wilfordii, saffron, curcumin, caffeine, anthocyanin, coenzyme Q10 and vitamins B3 and D have shown neuroprotective effects on retinal ganglion cells via various mechanisms, especially antioxidant, anti-inflammatory and anti-apoptosis mechanisms. Extensive studies are still required in the future to ensure natural products' efficacy and safety to serve as an alternative therapy for glaucoma.
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11
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Pujari R, Jampel HD. Treating Glaucoma with Medical Marijuana: Peering through the Smoke. Ophthalmol Glaucoma 2021; 2:201-203. [PMID: 32672538 DOI: 10.1016/j.ogla.2019.02.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Revised: 02/04/2019] [Accepted: 02/14/2019] [Indexed: 11/25/2022]
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12
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Kokona D, Spyridakos D, Tzatzarakis M, Papadogkonaki S, Filidou E, Arvanitidis KI, Kolios G, Lamani M, Makriyannis A, Malamas MS, Thermos K. The endocannabinoid 2-arachidonoylglycerol and dual ABHD6/MAGL enzyme inhibitors display neuroprotective and anti-inflammatory actions in the in vivo retinal model of AMPA excitotoxicity. Neuropharmacology 2021; 185:108450. [PMID: 33450278 DOI: 10.1016/j.neuropharm.2021.108450] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2020] [Revised: 12/17/2020] [Accepted: 01/03/2021] [Indexed: 12/14/2022]
Abstract
The endocannabinoid system has been shown to be a putative therapeutic target for retinal disease. Here, we aimed to investigate the ability of the endocannabinoid 2-arachidonoylglycerol (2-AG) and novel inhibitors of its metabolic enzymes, α/β-hydrolase domain-containing 6 (ABHD6) and monoacylglycerol lipase (MAGL), a) to protect the retina against excitotoxicity and b) the mechanisms involved in the neuroprotection. Sprague-Dawley rats, wild type and Akt2-/- C57BL/6 mice were intravitreally administered with phosphate-buffered saline or (RS)-α-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid hydrobromide (AMPA). 2-AG was intravitreally co-administered with AMPA in the absence and presence of AM251 or AM630 (cannabinoid 1 and 2 receptor antagonists, respectively) or Wortmannin [Phosphoinositide 3-Kinase (PI3K)/Akt inhibitor]. Inhibitors of ABHD6 and dual ABHD6/MAGL (AM12100 and AM11920, respectively) were co-administered with AMPA intravitreally in rats. Immunohistochemistry was performed using antibodies raised against retinal neuronal markers (bNOS), microglia (Iba1) and macroglia (GFAP). TUNEL assay and real-time PCR were also employed. The CB2 receptor was expressed in rat retina (approx. 62% of CB1 expression). 2-AG attenuated the AMPA-induced increase in TUNEL+ cells. 2-AG activation of both CB1 and CB2 receptors and the PI3K/Akt downstream signaling pathway, as substantiated by the use of Akt2-/- mice, afforded neuroprotection against AMPA excitotoxicity. AM12100 and AM11920 attenuated the AMPA-induced glia activation and produced a dose-dependent partial neuroprotection, with the dual inhibitor AM11920 being more efficacious. These results show that 2-AG has the pharmacological profile of a putative therapeutic for retinal diseases characterized by neurodegeneration and neuroinflammation, when administered exogenously or by the inhibition of its metabolic enzymes.
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Affiliation(s)
- Despina Kokona
- Department of Pharmacology, School of Medicine, University of Crete, Heraklion, Crete, 71003, Greece.
| | - Dimitris Spyridakos
- Department of Pharmacology, School of Medicine, University of Crete, Heraklion, Crete, 71003, Greece.
| | - Manolis Tzatzarakis
- Department of Toxicology, School of Medicine, University of Crete, Heraklion, Crete, 71003, Greece.
| | - Sofia Papadogkonaki
- Department of Pharmacology, School of Medicine, University of Crete, Heraklion, Crete, 71003, Greece.
| | - Eirini Filidou
- Laboratory of Pharmacology, School of Medicine, Democritus University of Thrace, Alexandroupolis, 68100, Greece.
| | - Konstantinos I Arvanitidis
- Laboratory of Pharmacology, School of Medicine, Democritus University of Thrace, Alexandroupolis, 68100, Greece.
| | - George Kolios
- Laboratory of Pharmacology, School of Medicine, Democritus University of Thrace, Alexandroupolis, 68100, Greece.
| | - Manjunath Lamani
- Center for Drug Discovery and Departments of Chemistry and Chemical Biology and Pharmaceutical Sciences, Northeastern University, Boston, MA, 02115, USA.
| | - Alexandros Makriyannis
- Center for Drug Discovery and Departments of Chemistry and Chemical Biology and Pharmaceutical Sciences, Northeastern University, Boston, MA, 02115, USA.
| | - Michael S Malamas
- Center for Drug Discovery and Departments of Chemistry and Chemical Biology and Pharmaceutical Sciences, Northeastern University, Boston, MA, 02115, USA.
| | - Kyriaki Thermos
- Department of Pharmacology, School of Medicine, University of Crete, Heraklion, Crete, 71003, Greece.
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13
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Cannabinoids in Glaucoma Patients: The Never-Ending Story. J Clin Med 2020; 9:jcm9123978. [PMID: 33302608 PMCID: PMC7763320 DOI: 10.3390/jcm9123978] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2020] [Revised: 11/26/2020] [Accepted: 12/04/2020] [Indexed: 12/18/2022] Open
Abstract
Glaucoma is one of the principal causes of irreversible blindness worldwide. Yet, intraocular pressure (IOP) is the main modifiable risk factor for disease progression. In the never-ending challenge to develop new and effective drugs, several molecules have been tested as anti-glaucoma agents thanks to their pressure-lowering capabilities. Among these molecules, the cannabinoids have been investigated as possible anti-glaucoma drugs since the early 1970s. Cannabinoids are a large class of chemical compounds that exploit their effects by interaction with cannabinoid receptors 1 and 2. These receptors are widely expressed in the human retina where they may influence important functions such as photo-transduction, amacrine cell network maintenance, and IOP regulation. Therefore, in past years several studies have been conducted in order to assess the IOP lowering effects of cannabinoids. PRISMA guidelines have been used to perform a literature search on Pubmed and Scopus aiming to investigate the mechanism of IOP lowering effects and the potential benefits of orally administered, inhaled, topical, and intravenous cannabinoids in the treatment of glaucoma patients.
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14
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Spyridakos D, Papadogkonaki S, Dionysopoulou S, Mastrodimou N, Polioudaki H, Thermos K. Effect of acute and subchronic administration of (R)-WIN55,212-2 induced neuroprotection and anti inflammatory actions in rat retina: CB1 and CB2 receptor involvement. Neurochem Int 2020; 142:104907. [PMID: 33220388 DOI: 10.1016/j.neuint.2020.104907] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Revised: 10/30/2020] [Accepted: 11/15/2020] [Indexed: 01/09/2023]
Abstract
Cannabinoids have been shown to protect the retina from ischemic/excitotoxic insults. The aim of the present study was to investigate the neuroprotective and anti-inflammatory properties of the synthetic cannabinoid (R)-WIN55,212-2 (CB1/CB2 receptor agonist) when administered acutely or subchronically in control and AMPA treated retinas. Sprague-Dawley rats were intravitreally administered (acutely) with vehicle or AMPA, in the absence or presence of (R)-WIN55,212-2 (10-7-10-4M) alone or in combination with AM251 [CB1 receptor antagonist/inverse agonist,10-4M] and AM630 (CB2 receptor antagonist,10-4M). In addition, AMPA was co-administered with the racemic (R,S)-WIN55,212 (10-4Μ). (R)-WIN55,212-2 was also administered subchronically (25,100 μg/kg,i.p.,4d) in control and AMPA treated rats. Immunohistochemical studies were performed using antibodies against the CB1R, and retinal markers for retinal neurons (brain nitric oxide synthetase, bNOS) and microglia (ionized calcium binding adaptor molecule 1, Iba1). ELISA assay was employed to assess TNFα levels in AMPA treated retinas. Intravitreal administration of (R)-WIN55,212-2 reversed the AMPA induced loss of bNOS expressing amacrine cells, an effect that was blocked by both AM251 and AM630. (R,S)WIN55,212 had no effect. (R)-WIN55,212-2 also reduced a) the AMPA induced activation of microglia, by activating CB2 receptors that were shown to be colocalized with Iba1+ reactive microglial cells, and b) TNFα levels in retina. (R)-WIN55,212-2 administered subchronically led to the downregulation of CB1 receptors at the high dose of 100 μg/kg(i.p.), and to the attenuation of the WIN55,212-2 induced neuroprotection of amacrine cells. At the same dose, (R)-WIN55,212-2 did not attenuate the AMPA induced increase in the number of reactive microglia cells, suggesting CB2 receptor downregulation under subchronic conditions. This study provides new findings regarding the role of CB1 and CB2 receptor activation by the synthetic cannabinoid (R)-WIN55,212-2, administered acutely or sub-chronically, on neuron viability and microglia activation in healthy and diseased retina.
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MESH Headings
- Animals
- Anti-Inflammatory Agents/administration & dosage
- Benzoxazines/administration & dosage
- Dose-Response Relationship, Drug
- Drug Administration Schedule
- Female
- Male
- Morpholines/administration & dosage
- Naphthalenes/administration & dosage
- Neuroprotective Agents/administration & dosage
- Rats
- Rats, Sprague-Dawley
- Receptor, Cannabinoid, CB1/agonists
- Receptor, Cannabinoid, CB1/metabolism
- Receptor, Cannabinoid, CB2/agonists
- Receptor, Cannabinoid, CB2/metabolism
- Retina/drug effects
- Retina/metabolism
- alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid/toxicity
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Affiliation(s)
- Dimitris Spyridakos
- Department of Pharmacology, School of Medicine, University of Crete, Heraklion, Crete, 71003, Greece.
| | - Sofia Papadogkonaki
- Department of Pharmacology, School of Medicine, University of Crete, Heraklion, Crete, 71003, Greece.
| | - Stavroula Dionysopoulou
- Department of Pharmacology, School of Medicine, University of Crete, Heraklion, Crete, 71003, Greece.
| | - Niki Mastrodimou
- Department of Pharmacology, School of Medicine, University of Crete, Heraklion, Crete, 71003, Greece.
| | - Hara Polioudaki
- Department of Biochemistry, School of Medicine, University of Crete, Heraklion, Crete, 71003, Greece.
| | - Kyriaki Thermos
- Department of Pharmacology, School of Medicine, University of Crete, Heraklion, Crete, 71003, Greece.
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15
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Souza Monteiro de Araújo D, De Logu F, Adembri C, Rizzo S, Janal MN, Landini L, Magi A, Mattei G, Cini N, Pandolfo P, Geppetti P, Nassini R, Calaza KDC. TRPA1 mediates damage of the retina induced by ischemia and reperfusion in mice. Cell Death Dis 2020; 11:633. [PMID: 32801314 PMCID: PMC7429961 DOI: 10.1038/s41419-020-02863-6] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Revised: 08/02/2020] [Accepted: 08/03/2020] [Indexed: 12/16/2022]
Abstract
Oxidative stress is implicated in retinal cell injury associated with glaucoma and other retinal diseases. However, the mechanism by which oxidative stress leads to retinal damage is not completely understood. Transient receptor potential ankyrin 1 (TRPA1) is a redox-sensitive channel that, by amplifying the oxidative stress signal, promotes inflammation and tissue injury. Here, we investigated the role of TRPA1 in retinal damage evoked by ischemia (1 hour) and reperfusion (I/R) in mice. In wild-type mice, retinal cell numbers and thickness were reduced at both day-2 and day-7 after I/R. By contrast, mice with genetic deletion of TRPA1 were protected from the damage seen in their wild-type littermates. Daily instillation of eye drops containing two different TRPA1 antagonists, an oxidative stress scavenger, or a NADPH oxidase-1 inhibitor also protected the retinas of C57BL/6J mice exposed to I/R. Mice with genetic deletion of the proinflammatory TRP channels, vanilloid 1 (TRPV1) or vanilloid 4 (TRPV4), were not protected from I/R damage. Surprisingly, genetic deletion or pharmacological blockade of TRPA1 also attenuated the increase in the number of infiltrating macrophages and in the levels of the oxidative stress biomarker, 4-hydroxynonenal, and of the apoptosis biomarker, active caspase-3, evoked by I/R. These findings suggest that TRPA1 mediates the oxidative stress burden and inflammation that result in murine retinal cell death. We also found that TRPA1 (both mRNA and protein) is expressed by human retinal cells. Thus, it is possible that inhibition of a TRPA1-dependent pathway could also attenuate glaucoma-related retinal damage.
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Affiliation(s)
- Daniel Souza Monteiro de Araújo
- Department of Neurobiology and Program of Neurosciences, Institute of Biology, Fluminense Federal University, Niterói, Brazil.,Department of Health Sciences, Section of Clinical Pharmacology and Oncology, University of Florence, Florence, Italy
| | - Francesco De Logu
- Department of Health Sciences, Section of Clinical Pharmacology and Oncology, University of Florence, Florence, Italy
| | - Chiara Adembri
- Department of Health Sciences, Section of Clinical Pharmacology and Oncology, University of Florence, Florence, Italy
| | - Stanislao Rizzo
- Department of Neurosciences, Psychology, Drug Research and Child Health (NeuroFarBa), Division of Ophthalmology, University of Florence, Florence, Italy
| | - Malvin N Janal
- Department of Epidemiology and Health Promotion, New York University College of Dentistry, New York, NY, USA
| | - Lorenzo Landini
- Department of Health Sciences, Section of Clinical Pharmacology and Oncology, University of Florence, Florence, Italy
| | - Alberto Magi
- Department of Information Engineering, University of Florence, Florence, Italy
| | - Gianluca Mattei
- Department of Information Engineering, University of Florence, Florence, Italy
| | - Nicoletta Cini
- General Laboratory, Careggi University Hospital, Florence, Italy
| | - Pablo Pandolfo
- Department of Neurobiology and Program of Neurosciences, Institute of Biology, Fluminense Federal University, Niterói, Brazil
| | - Pierangelo Geppetti
- Department of Health Sciences, Section of Clinical Pharmacology and Oncology, University of Florence, Florence, Italy
| | - Romina Nassini
- Department of Health Sciences, Section of Clinical Pharmacology and Oncology, University of Florence, Florence, Italy.
| | - Karin da Costa Calaza
- Department of Neurobiology and Program of Neurosciences, Institute of Biology, Fluminense Federal University, Niterói, Brazil
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16
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Abstract
Cannabis ranks among the most commonly used psychotropic drugs worldwide. In the context of the global movement toward more widespread legalisation, there is a growing need toward developing a better understanding of the physiological and pathological effects. We provide an overview of the current evidence on the effects of cannabinoids on the eye. Of the identified cannabinoids, Δ9-tetrahydrocannabinol is recognized to be the primary psychotropic compound, and cannabidiol is the predominant nonpsychoactive ingredient. Despite demonstrating ocular hypotensive and neuroprotective activity, the use of cannabinoids as a treatment for glaucoma is limited by a large number of potential systemic and ophthalmic side effects. Anterior segment effects of cannabinoids are complex, with preliminary evidence showing decreased corneal endothelial density in chronic cannabinoid users. Experiments in rodents, however, have shown potential promise for the treatment of ocular surface injury via antinociceptive and antiinflammatory effects. Electroretinography studies demonstrating adverse effects on photoreceptor, bipolar, and ganglion cell function suggest links between cannabis and neuroretinal dysfunction. Neuro-ophthalmic associations include ocular motility deficits and decrements in smooth pursuit and saccadic eye movements, although potential therapeutic effects for congenital and acquired nystagmus have been observed.
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17
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Ferreira C, Couceiro J, Família C, Jardim C, Antas P, Santos CN, Outeiro TF, Tenreiro S, Quintas A. The synthetic cannabinoid JWH-018 modulates Saccharomyces cerevisiae energetic metabolism. FEMS Yeast Res 2020; 19:5521208. [PMID: 31329229 DOI: 10.1093/femsyr/foz042] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Accepted: 06/18/2019] [Indexed: 02/07/2023] Open
Abstract
Synthetic cannabinoids are a group of novel psychoactive substances with similar properties to Δ9-THC. Among the vast number of synthetic cannabinoids, designed to be tested in clinical trials, JWH-018 was the first novel psychoactive substance found in the recreational drug marketplace. The consumption of JWH-018 shows typical effects of CB1 agonists including sedation, cognitive dysfunction, tachycardia, postural hypotension, dry mouth, ataxia and psychotropic effects, but appeared to be more potent than Δ9-THC. However, studies on human cells have shown that JWH-018 toxicity depends on the cellular line used. Despite these studies, the underlying molecular mechanisms to JWH-018 action has not been clarified yet. To understand the impact of JWH-018 at molecular and cellular level, we used Saccharomyces cerevisiae as a model. The results showed an increase in yeast growth rate in the presence of this synthetic cannabinoid due to an enhancement in the glycolytic flux at expense of a decrease in pentose phosphate pathway, judging by 2D-Gel proteomic analysis, qRT-PCR experiments and ATP measurements. Overall, our results provide insights into molecular mechanisms of JWH-018 action, also indicating that Saccharomyces cerevisiae is a good model to study synthetic cannabinoids.
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Affiliation(s)
- Carla Ferreira
- Molecular Pathology and Forensic Biochemistry Laboratory, Centro de Investigação Interdisciplinar Egas Moniz, P-2825-084 Caparica, Portugal.,Laboratório de Ciências Forenses e Psicológicas Egas Moniz, Campus Universitário - Quinta da Granja, Monte de Caparica, P-2825-084 Caparica, Portugal.,Faculty of Medicine of Porto University, Al. Prof. Hernâni Monteiro, P-4200-319 Porto, Portugal
| | - Joana Couceiro
- Molecular Pathology and Forensic Biochemistry Laboratory, Centro de Investigação Interdisciplinar Egas Moniz, P-2825-084 Caparica, Portugal.,Laboratório de Ciências Forenses e Psicológicas Egas Moniz, Campus Universitário - Quinta da Granja, Monte de Caparica, P-2825-084 Caparica, Portugal
| | - Carlos Família
- Molecular Pathology and Forensic Biochemistry Laboratory, Centro de Investigação Interdisciplinar Egas Moniz, P-2825-084 Caparica, Portugal.,Laboratório de Ciências Forenses e Psicológicas Egas Moniz, Campus Universitário - Quinta da Granja, Monte de Caparica, P-2825-084 Caparica, Portugal
| | - Carolina Jardim
- Instituto de Biologia Experimental e Tecnológica, Apartado 12, P-2780-901 Oeiras, Portugal.,Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Av. da República, P-2780-157 Oeiras, Portugal
| | - Pedro Antas
- CEDOC - Chronic Diseases Research Center, Faculdade de Ciências Médicas, Universidade Nova de Lisboa, P-1150-082 Lisboa, Portugal
| | - Cláudia N Santos
- Instituto de Biologia Experimental e Tecnológica, Apartado 12, P-2780-901 Oeiras, Portugal.,Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Av. da República, P-2780-157 Oeiras, Portugal.,CEDOC - Chronic Diseases Research Center, Faculdade de Ciências Médicas, Universidade Nova de Lisboa, P-1150-082 Lisboa, Portugal
| | - Tiago F Outeiro
- CEDOC - Chronic Diseases Research Center, Faculdade de Ciências Médicas, Universidade Nova de Lisboa, P-1150-082 Lisboa, Portugal.,Department of Experimental Neurodegeneration, Center for Nanoscale Microscopy and Molecular Physiology of the Brain, University Medical Center Göttingen, Waldweg 33. Göttingen P37073, Germany.,Institute of Neuroscience, Medical School, Newcastle University, Framlington Place, Newcastle Upon Tyne P-NE1 7RU, UK.,Max Planck Institute for Experimental Medicine, Hermann Rein Street 3. P-37075 Göttingen, Germany
| | - Sandra Tenreiro
- CEDOC - Chronic Diseases Research Center, Faculdade de Ciências Médicas, Universidade Nova de Lisboa, P-1150-082 Lisboa, Portugal
| | - Alexandre Quintas
- Molecular Pathology and Forensic Biochemistry Laboratory, Centro de Investigação Interdisciplinar Egas Moniz, P-2825-084 Caparica, Portugal.,Laboratório de Ciências Forenses e Psicológicas Egas Moniz, Campus Universitário - Quinta da Granja, Monte de Caparica, P-2825-084 Caparica, Portugal
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18
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Papadogkonaki S, Theodorakis Κ, Thermos K. Endogenous and synthetic cannabinoids induce the downregulation of cannabinoid CB1 receptor in retina. Exp Eye Res 2019; 185:107694. [DOI: 10.1016/j.exer.2019.107694] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Revised: 05/20/2019] [Accepted: 06/10/2019] [Indexed: 10/26/2022]
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19
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Abstract
Cannabinoid receptors, endocannabinoids and the enzymes responsible for their biosynthesis and degradation constitute the endocannabinoid system. In recent decades, the endocannabinoid system has attracted considerable interest as a potential therapeutic target in numerous pathological conditions. Its involvement in several physiological processes is well known, such as in energy balance, appetite stimulation, blood pressure, pain modulation, embryogenesis, nausea and vomiting control, memory, learning and immune response, among others, as well as in pathological conditions where it exerts a protective role in the development of certain disorders. As a result, it has been reported that changes in endocannabinoid levels may be related to neurological diseases such as Parkinson's disease, Huntington's disease, Alzheimer's disease and multiple sclerosis, as well as anorexia and irritable bowel syndrome. Alterations in the endocannabinoid system have also been associated with cancer, affecting the growth, migration and invasion of some tumours. Cannabinoids have been tested in several cancer types, including brain, breast and prostate cancers. Cannabinoids have shown promise as analgesics for the treatment of both inflammatory and neuropathic pain. There is also evidence for a role of the endocannabinoid system in the control of emotional states, and cannabinoids could prove useful in decreasing and palliating post-traumatic stress disorder symptoms and anxiolytic disorders. The role of the endocannabinoid system in addictions has also been examined, and cannabinoids have been postulated as alternative and co-adjuvant treatments in some abuse syndromes, mainly in ethanol and opioid abuses. The expression of the endocannabinoid system in the eye suggests that it could be a potential therapeutic target for eye diseases. Considering the importance of the endocannabinoid system and the therapeutic potential of cannabinoids in this vast number of medical conditions, several clinical studies with cannabinoid-based medications are ongoing. In addition, some cannabinoid-based medications have already been approved in various countries, including nabilone and dronabinol capsules for the treatment of nausea and vomiting associated with chemotherapy, dronabinol capsules for anorexia, an oral solution of dronabinol for both vomiting associated with chemotherapy and anorexia, a Δ9-tetrahydrocannabinol/cannabidiol oromucosal spray for pain related to cancer and for spasticity and pain associated with multiple sclerosis, and an oral solution of cannabidiol for Dravet and Lennox-Gastaut syndromes. Here, we review the available efficacy, safety and tolerability data for cannabinoids in a range of medical conditions.
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Affiliation(s)
- Ana Isabel Fraguas-Sánchez
- Department of Pharmaceutics and Food Technology, Faculty of Pharmacy, Plaza Ramón y Cajal s/n, 28040 , Madrid, Spain
| | - Ana Isabel Torres-Suárez
- Department of Pharmaceutics and Food Technology, Faculty of Pharmacy, Plaza Ramón y Cajal s/n, 28040 , Madrid, Spain. .,Institute of Industrial Pharmacy, Complutense University of Madrid, 28040 , Madrid, Spain.
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20
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Abstract
Osteopontin (OPN) is a secreted glycosylated phosphoprotein that influences cell survival, inflammation, migration, and homeostasis after injury. As the role of OPN in the retina remains unclear, this study issue was addressed by aiming to study how the absence of OPN in knock-out mice affects the retina and the influence of age on these effects. The study focused on retinal ganglion cells (RGCs) and glial cells (astrocytes, Müller cells, and resident microglia) in 3- and 20-month-old mice. The number of RGCs in the retina was quantified and the area occupied by astrocytes was measured. In addition, the morphology of Müller cells and microglia was examined in retinal sections. The deficiency in OPN reduces RGC density by 25.09% at 3 months of age and by 60.37% at 20 months of age. The astrocyte area was also reduced by 51.01% in 3-month-old mice and by 57.84% at 20 months of age, although Müller glia and microglia did not seem to be affected by the lack of OPN. This study demonstrates the influence of OPN on astrocytes and RGCs, whereby the absence of OPN in the retina diminishes the area occupied by astrocytes and produces a secondary reduction in the number of RGCs. Accordingly, OPN could be a target to develop therapies to combat neurodegenerative diseases and astrocytes may represent a key mediator of such effects.
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21
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The Endocannabinoid System Is Present in Rod Outer Segments from Retina and Is Modulated by Light. Mol Neurobiol 2019; 56:7284-7295. [PMID: 31016476 DOI: 10.1007/s12035-019-1603-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Accepted: 04/10/2019] [Indexed: 10/27/2022]
Abstract
The aim of the present research was to evaluate if the endocannabinoid system (enzymes and receptors) could be modulated by light in rod outer segment (ROS) from bovine retina. First, we analyzed endocannabinoid 2-arachidonoylglycerol (2-AG) metabolism in purified ROS obtained from dark-adapted (DROS) or light-adapted (LROS) retinas. To this end, diacylglycerol lipase (DAGL), monoacylglycerol lipase (MAGL), and lysophosphatidate phosphohydrolase (LPAP) enzymatic activities were analyzed using radioactive substrates. The protein content of these enzymes and of the receptors to which cannabinoids bind was determined by immunoblotting under light stimulus. Our results indicate that whereas DAGL and MAGL activities were stimulated in retinas exposed to light, no changes were observed in LPAP activity. Interestingly, the protein content of the main enzymes involved in 2-AG metabolism, phospholipase C β1 (PLCβ1), and DAGLα (synthesis), and MAGL (hydrolysis), was also modified by light. PLCβ1 content was increased, while that of lipases was decreased. On the other hand, light produced an increase in the cannabinoid receptors CB1 and CB2 and a decrease in GPR55 protein levels. Taken together, our results indicate that the endocannabinoid system (enzymes and receptors) depends on the illumination state of the retina, suggesting that proteins related to phototransduction phenomena could be involved in the effects observed.
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Lax P, Kutsyr O, Esquiva G, Altavilla C, Maneu V, Cuenca N. Cannabinoid-mediated retinal rescue correlates with improved circadian parameters in retinal dystrophic rats. Exp Eye Res 2019; 180:192-199. [DOI: 10.1016/j.exer.2018.12.022] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Revised: 11/13/2018] [Accepted: 12/30/2018] [Indexed: 11/15/2022]
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Jiang MN, Zhou YY, Hua DH, Yang JY, Hu ML, Xing YQ. Vagal Nerve Stimulation Attenuates Ischemia-Reperfusion Induced Retina Dysfunction in Acute Ocular Hypertension. Front Neurosci 2019; 13:87. [PMID: 30804746 PMCID: PMC6378858 DOI: 10.3389/fnins.2019.00087] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Accepted: 01/25/2019] [Indexed: 12/19/2022] Open
Abstract
Purpose: The present study aimed to investigate whether cervical vagal nerve stimulation (VNS) could prevent retinal ganglion cell (RGC) loss and retinal dysfunction after ischemia/reperfusion (I/R) injury. Methods: First, rats were randomly divided into sham group (n = 4) and VNS group (n = 12). Activation of the nodose ganglia (NOG), nucleus of the solitary tract (NTS), superior salivatory nucleus (SSN), and pterygopalatine ganglion (PPG) neural circuit were evaluated by c-fos expression at 0 h after sham VNS and at 0 h (n = 4), 6 h (n = 4), 72 h (n = 4) after VNS. Secondly, rats were randomly assigned to I/R group (pressure-induced retinal ischemia for 1 h and reperfusion for 1 h in the right eye, n = 16) and I/R+VNS group (right cervical VNS for 2 h during the I/R period, n = 16). The left eye of each rat served as a control. Electroretinogram (ERG), RGC numbers, tumor necrosis factor-α (TNF-α) and vasoactive intestinal polypeptide (VIP) levels in retina were determined. Additionally, the level of VIP in PPG was evaluated. Results: In the first part of the study, compared with the sham group, the VNS group exhibited significantly increased expression of c-fos in NOG, NTS, SSN, and PPG tissues at 0, 6, and 72 h. In the second part of the study, compared with left eyes, retinal function in right eyes (as assessed by the a-wave, b-wave and the oscillatory potential amplitudes of ERG and RGC data) was significantly decreased by I/R. The decreased retinal function was attenuated by VNS. In addition, I/R induced an increase in inflammation, which was reflected by elevated TNF-α expression in the retina. VNS significantly attenuated the increase in I/R-induced inflammation. Moreover, VIP expression in the retina and PPG, which may contribute to the inhibition of the inflammatory response, was significantly increased after VNS. Conclusion: VNS could protect against retinal I/R injury by downregulating TNF-α. Upregulation of VIP expression due to activation of the NOG-NTS-SSN-PPG neural circuit may underlie to the protective effects of VNS.
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Affiliation(s)
- Meng-Nan Jiang
- Eye Center, Renmin Hospital of Wuhan University, Wuhan, China
| | - Yu-Yang Zhou
- Eye Center, Renmin Hospital of Wuhan University, Wuhan, China
| | - Di-Hao Hua
- Eye Center, Renmin Hospital of Wuhan University, Wuhan, China
| | - Jia-Yi Yang
- Eye Center, Renmin Hospital of Wuhan University, Wuhan, China
| | - Man-Li Hu
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Yi-Qiao Xing
- Eye Center, Renmin Hospital of Wuhan University, Wuhan, China
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Chen Y, Luo X, Liu S, Shen Y. Neuroprotective effect of cannabinoid receptor 1 antagonist in the MNU-induced retinal degeneration model. Exp Eye Res 2017; 167:145-151. [PMID: 29126840 DOI: 10.1016/j.exer.2017.11.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2017] [Revised: 11/02/2017] [Accepted: 11/06/2017] [Indexed: 11/16/2022]
Abstract
Endocannabinoid system involves in neuroprotective effects on the central neural system. The cannabinoid receptor 1 (CB1R) is widely expressed in the mouse retina. However, the role of cannabinoid receptors in the retina remains unclear. In this work, we established a photoreceptor degeneration mouse model via N-methyl-N-nitrosourea (MNU) administration to identify the neuroprotective effects of cannabinoid receptors. The MNU-induced retinal degeneration behaves similarly to that in the human retinitis pigmentosa (RP). Administration of the CB1R antagonist SR141716A distinctly recovered the photoreceptor loss, decreased glial reactivity and reduced abnormal vascular complexes in an MNU-induced mouse model. The BC dendrites were shrunk in the MNU-treated retina with eliminated ON-BCs responses and partially diminished OFF-BCs responses in patch-clamp recordings. In the MNU + SR1 group, both the function and structure of ON-BCs recovered. Taken together, our study showed that the inhibition of CB1R can effectively prevent MNU-induced retinal degeneration, suggesting a potential therapeutic effect of the CB1R antagonist SR1 in retinal degeneration diseases.
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Affiliation(s)
- Yuanyuan Chen
- Eye Center, Renmin Hospital of Wuhan University, Wuhan 430060, PR China
| | - Xue Luo
- Eye Center, Renmin Hospital of Wuhan University, Wuhan 430060, PR China
| | - Shiliang Liu
- Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095 Jiefang Avenue, Wuhan, 430030, PR China
| | - Yin Shen
- Eye Center, Renmin Hospital of Wuhan University, Wuhan 430060, PR China.
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Jo AO, Noel JM, Lakk M, Yarishkin O, Ryskamp DA, Shibasaki K, McCall MA, Križaj D. Mouse retinal ganglion cell signalling is dynamically modulated through parallel anterograde activation of cannabinoid and vanilloid pathways. J Physiol 2017; 595:6499-6516. [PMID: 28766743 PMCID: PMC5638913 DOI: 10.1113/jp274562] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2017] [Accepted: 07/27/2017] [Indexed: 01/19/2023] Open
Abstract
KEY POINTS Retinal cells use vanilloid transient receptor potential (TRP) channels to integrate light-evoked signals with ambient mechanical, chemical and temperature information. Localization and function of the polymodal non-selective cation channel TRPV1 (transient receptor potential vanilloid isoform 1) remains elusive. TRPV1 is expressed in a subset of mouse retinal ganglion cells (RGCs) with peak expression in the mid-peripheral retina. Endocannabinoids directly activate TRPV1 and inhibit it through cannabinoid type 1 receptors (CB1Rs) and cAMP pathways. Activity-dependent endocannabinoid release may modulate signal gain in RGCs through simultaneous manipulation of calcium and cAMP signals mediated by TRPV1 and CB1R. ABSTRACT How retinal ganglion cells (RGCs) process and integrate synaptic, mechanical, swelling stimuli with light inputs is an area of intense debate. The nociceptive cation channel TRPV1 (transient receptor potential vanilloid type 1) modulates RGC Ca2+ signals and excitability yet the proportion of RGCs that express it remains unclear. Furthermore, TRPV1's response to endocannabinoids (eCBs), the putative endogenous retinal activators, is unknown, as is the potential modulation by cannabinoid receptors (CBRs). The density of TRPV1-expressing RGCs in the Ai9:Trpv1 reporter mouse peaked in the mid-peripheral retina. TRPV1 agonists including capsaicin (CAP) and the eCBs anandamide and N-arachidonoyl-dopamine elevated [Ca2+ ]i in 30-40% of wild-type RGCs, with effects suppressed by TRPV1 antagonists capsazepine (CPZ) and BCTC ((4-(3-chloro-2-pyridinyl)-N-[4-(1,1-dimethylethyl)phenyl]-1-piperazinecarboxamide), and lacking in Trpv1-/- cells. The cannabinoid receptor type 1 (CB1R) colocalized with TRPV1:tdTomato expression. Its agonists 2-arachidonoylglycerol (2-AG) and WIN55,122 inhibited CAP-induced [Ca2+ ]i signals in adult, but not early postnatal, RGCs. The suppressive effect of 2-AG on TRPV1 activation was emulated by positive modulators of the protein kinase A (PKA) pathway, inhibited by the CB1R antagonist rimonabant and Gi uncoupler pertussis toxin, and absent in Cnr1-/- RGCs. We conclude that TRPV1 is a modulator of Ca2+ homeostasis in a subset of RGCs that show non-uniform distribution across the mouse retina. Non-retrograde eCB-mediated modulation of RGC signalling involves a dynamic push-pull between direct TRPV1 activation and PKA-dependent regulation of channel inactivation, with potential functions in setting the bandwidth of postsynaptic responses, sensitivity to mechanical/excitotoxic stress and neuroprotection.
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Affiliation(s)
- Andrew O. Jo
- Department of Ophthalmology & Visual SciencesMoran Eye InstituteSalt Lake CityUTUSA
| | - Jennifer M. Noel
- Department of Anatomical Sciences and NeurobiologyUniversity of LouisvilleLouisvilleKYUSA
| | - Monika Lakk
- Department of Ophthalmology & Visual SciencesMoran Eye InstituteSalt Lake CityUTUSA
| | - Oleg Yarishkin
- Department of Ophthalmology & Visual SciencesMoran Eye InstituteSalt Lake CityUTUSA
| | - Daniel A. Ryskamp
- Department of Ophthalmology & Visual SciencesMoran Eye InstituteSalt Lake CityUTUSA
- Interdepartmental Program in NeuroscienceUniversity of Utah School of MedicineSalt Lake CityUTUSA
| | | | - Maureen A. McCall
- Department of Anatomical Sciences and NeurobiologyUniversity of LouisvilleLouisvilleKYUSA
- Department of Ophthalmology & Visual SciencesUniversity of LouisvilleLouisvilleKYUSA
| | - David Križaj
- Department of Ophthalmology & Visual SciencesMoran Eye InstituteSalt Lake CityUTUSA
- Interdepartmental Program in NeuroscienceUniversity of Utah School of MedicineSalt Lake CityUTUSA
- Department of Neurobiology & AnatomyUniversity of Utah School of MedicineSalt Lake CityUTUSA
- Department of BioengineeringUniversity of Utah School of MedicineSalt Lake CityUTUSA
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Cairns EA, Szczesniak AM, Straiker AJ, Kulkarni PM, Pertwee RG, Thakur GA, Baldridge WH, Kelly MEM. The In Vivo Effects of the CB 1-Positive Allosteric Modulator GAT229 on Intraocular Pressure in Ocular Normotensive and Hypertensive Mice. J Ocul Pharmacol Ther 2017; 33:582-590. [PMID: 28719234 DOI: 10.1089/jop.2017.0037] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
PURPOSE Orthosteric cannabinoid receptor 1 (CB1) activation leads to decreases in intraocular pressure (IOP). However, use of orthosteric CB1 agonists chronically has several disadvantages, limiting their usefulness as clinically relevant drugs. Allosteric modulators interact with topographically distinct sites to orthosteric ligands and may be useful to circumvent some of these disadvantages. The purpose of this study was to investigate the effects of the novel CB1-positive allosteric modulator (PAM) GAT229 on IOP. METHODS IOP was measured using rebound tonometry in anesthetized normotensive C57Bl/6 mice and in a genetic model of ocular hypertension [nose, eyes, ears (nee) mice] before drug administration, and at 1, 6, and 12 h thereafter. RESULTS In normotensive mice, topical administration of 5 μL GAT229 alone at either 0.2% or 2% did not reduce IOP. However, a subthreshold dose (0.25%) of the nonselective orthosteric CB1 agonist WIN 55,212-2, when combined with 0.2% GAT229, significantly reduced IOP compared with vehicle at 6 and 12 h. Similarly, combination of subthreshold Δ9-tetrahydrocannabinol (a nonselective orthosteric CB1 agonist; 1 mg/kg) with topical 0.2% GAT229 produced IOP lowering at 6 h. In nee mice, administration of topical 0.2% GAT229 or 10 mg/kg GAT229 alone was sufficient to lower IOP at 6 and 12 h, and 12 h, respectively. CONCLUSIONS The CB1 PAM GAT229 reduces IOP in ocular hypertensive mice and enhanced CB1-mediated IOP reduction when combined with subthreshold CB1 orthosteric ligands in normotensive mice. Administration of CB1 PAMs may provide a novel approach to reduce IOP with fewer of the disadvantages associated with orthosteric CB1 activation.
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Affiliation(s)
- Elizabeth A Cairns
- 1 Department of Pharmacology, Dalhousie University , Halifax, Nova Scotia, Canada
| | | | - Alex J Straiker
- 2 Department of Psychological and Brain Sciences, Indiana University , Bloomington, Indiana
| | - Pushkar M Kulkarni
- 3 Department of Pharmaceutical Sciences School of Pharmacy, Bouvé College of Health Sciences, Northeastern University , Boston, Massachusetts
| | - Roger G Pertwee
- 4 School of Medicine, Medical Sciences, and Nutrition, Institute of Medical Sciences, University of Aberdeen , Aberdeen, Scotland
| | - Ganesh A Thakur
- 3 Department of Pharmaceutical Sciences School of Pharmacy, Bouvé College of Health Sciences, Northeastern University , Boston, Massachusetts
| | - William H Baldridge
- 5 Department of Medical Neuroscience, Dalhousie University , Halifax, Nova Scotia, Canada .,6 Department of Ophthalmology and Visual Sciences, Dalhousie University , Halifax, Nova Scotia, Canada
| | - Melanie E M Kelly
- 1 Department of Pharmacology, Dalhousie University , Halifax, Nova Scotia, Canada .,6 Department of Ophthalmology and Visual Sciences, Dalhousie University , Halifax, Nova Scotia, Canada
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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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Ruzafa N, Rey-Santano C, Mielgo V, Pereiro X, Vecino E. Effect of hypoxia on the retina and superior colliculus of neonatal pigs. PLoS One 2017; 12:e0175301. [PMID: 28407001 PMCID: PMC5391064 DOI: 10.1371/journal.pone.0175301] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2016] [Accepted: 03/23/2017] [Indexed: 11/20/2022] Open
Abstract
Purpose To evaluate the effect of hypoxia on the neonatal pig retina and brain, we analysed the retinal ganglion cells (RGCs) and neurons in the superior colliculus, as well as the response of astrocytes in both these central nervous system (CNS) structures. Methods Newborn pigs were exposed to 120 minutes of hypoxia, induced by decreasing the inspiratory oxygen fraction (FiO2: 10–15%), followed by a reoxygenation period of 240 minutes (FiO2: 21–35%). RGCs were quantified using Brn3a, a specific nuclear marker for these cells, and apoptosis was assessed through the appearance of active caspase-3. A morphometric analysis of the cytoskeleton of astrocytes (identified with GFAP) was performed in both the retina and superior colliculus. Results Hypoxia produced no significant change in the RGCs, although, it did induce a 37.63% increase in the number of active caspase-3 positive cells in the superior colliculus. This increase was particularly evident in the superficial layers of the superior colliculus, where 56.93% of the cells were positive for active caspase-3. In addition, hypoxia induced changes in the morphology of the astrocytes in the superior colliculus but not in the retina. Conclusions Hypoxia in the neonatal pig does not affect the retina but it does affect more central structures in the brain, increasing the number of apoptotic cells in the superior colliculus and inducing changes in astrocyte morphology. This distinct sensibility to hypoxia may pave the way to design specific approaches to combat the effects of hypoxia in specific areas of the CNS.
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Affiliation(s)
- Noelia Ruzafa
- Department of Cell Biology and Histology, University of Basque Country UPV/EHU, Leioa, Vizcaya, Spain
| | - Carmen Rey-Santano
- Research Unit for Experimental Neonatal Respiratory Physiology, Cruces University Hospital, Barakaldo, Vizcaya, Spain
| | - Victoria Mielgo
- Research Unit for Experimental Neonatal Respiratory Physiology, Cruces University Hospital, Barakaldo, Vizcaya, Spain
| | - Xandra Pereiro
- Department of Cell Biology and Histology, University of Basque Country UPV/EHU, Leioa, Vizcaya, Spain
| | - Elena Vecino
- Department of Cell Biology and Histology, University of Basque Country UPV/EHU, Leioa, Vizcaya, Spain
- * E-mail:
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The arguments for and against cannabinoids application in glaucomatous retinopathy. Biomed Pharmacother 2016; 86:620-627. [PMID: 28027538 DOI: 10.1016/j.biopha.2016.11.106] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2016] [Revised: 11/21/2016] [Accepted: 11/27/2016] [Indexed: 01/22/2023] Open
Abstract
Glaucoma represents several optic neuropathies leading to irreversible blindness through progressive retinal ganglion cell (RGC) loss. Reduction of intraocular pressure (IOP) is known as the only modifiable factor in the treatment of this disorder. Application of exogenous cannabinoids to lower IOP has attracted attention of scientists as potential agents for the treatment of glaucoma. Accordingly, neuroprotective effect of these agents has been recently described through modulation of endocannabinoid system in the eye. In the present work, pertinent information regarding ocular endocannabinoid system, mechanism of exogenous cannabinoids interaction with the ocular endocannabinoid system to reduce IOP, and neuroprotection property of cannabinoids will be discussed according to current scientific literature. In addition to experimental studies, bioavailability of cannabinoids, clinical surveys, and adverse effects of application of cannabinoids in glaucoma will be reviewed.
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Araújo DSM, Miya-Coreixas VS, Pandolfo P, Calaza KC. Cannabinoid receptors and TRPA1 on neuroprotection in a model of retinal ischemia. Exp Eye Res 2016; 154:116-125. [PMID: 27876485 DOI: 10.1016/j.exer.2016.11.015] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Revised: 11/11/2016] [Accepted: 11/18/2016] [Indexed: 12/16/2022]
Abstract
Retinal ischemia is a pathological event present in several retinopathies such as diabetic retinopathy and glaucoma, leading to partial or full blindness with no effective treatment available. Since synthetic and endogenous cannabinoids have been studied as modulators of ischemic events in the central nervous system (CNS), the present study aimed to investigate the involvement of cannabinoid system in the cell death induced by ischemia in an avascular (chick) retina. We observed that chick retinal treatment with a combination of WIN 55212-2 and cannabinoid receptor antagonists (either AM251/O-2050 or AM630) decreased the release of lactate dehydrogenase (LDH) induced by retinal ischemia in an oxygen and glucose deprivation (OGD) model. Further, the increased availability of endocannabinoids together with cannabinoid receptor antagonists also had a neuroprotective effect. Surprisingly, retinal exposure to any of these drugs alone did not prevent the release of LDH stimulated by OGD. Since cannabinoids may also activate transient receptor potential (TRP) channels, we investigated the involvement of TRPA1 receptors (TRPA1) in retinal cell death induced by ischemic events. We demonstrated the presence of TRPA1 in the chick retina, and observed an increase in TRPA1 content after OGD, both by western blot and immunohistochemistry. In addition, the selective activation of TRPA1 by mustard oil (MO) did not worsen retinal LDH release induced by OGD, whereas the blockage of TRPA1 completely prevented the extravasation of cellular LDH in ischemic condition. Hence, these results show that during the ischemic event there is an augment of TRPA1, and activation of this receptor is important in cell death induction. The data also indicate that metabotropic cannabinoid receptors, both type 1 and 2, are not involved with the cell death found in the early stages of ischemia. Therefore, the study points to a potential role of TRPA1 as a target for neuroprotective approaches in retinal ischemia.
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Affiliation(s)
- D S M Araújo
- Laboratory of Neurobiology of the Retina, Department of Neurobiology and Program of Neurosciences, Institute of Biology, Fluminense Federal University, Niterói, RJ, Brazil
| | - V S Miya-Coreixas
- Laboratory of Neurobiology of the Retina, Department of Neurobiology and Program of Neurosciences, Institute of Biology, Fluminense Federal University, Niterói, RJ, Brazil
| | - P Pandolfo
- Laboratory of Neurobiology of Animal Behavior, Department of Neurobiology and Program of Neurosciences, Institute of Biology, Fluminense Federal University, Niterói, RJ, Brazil
| | - K C Calaza
- Laboratory of Neurobiology of the Retina, Department of Neurobiology and Program of Neurosciences, Institute of Biology, Fluminense Federal University, Niterói, RJ, Brazil.
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Duanmu WS, Cao L, Chen JY, Ge HF, Hu R, Feng H. Ischemic postconditioning protects against ischemic brain injury by up-regulation of acid-sensing ion channel 2a. Neural Regen Res 2016; 11:641-5. [PMID: 27212927 PMCID: PMC4870923 DOI: 10.4103/1673-5374.180751] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2016] [Indexed: 12/25/2022] Open
Abstract
Ischemic postconditioning renders brain tissue tolerant to brain ischemia, thereby alleviating ischemic brain injury. However, the exact mechanism of action is still unclear. In this study, a rat model of global brain ischemia was subjected to ischemic postconditioning treatment using the vessel occlusion method. After 2 hours of ischemia, the bilateral common carotid arteries were blocked immediately for 10 seconds and then perfused for 10 seconds. This procedure was repeated six times. Ischemic postconditioning was found to mitigate hippocampal CA1 neuronal damage in rats with brain ischemia, and up-regulate acid-sensing ion channel 2a expression at the mRNA and protein level. These findings suggest that ischemic postconditioning up-regulates acid-sensing ion channel 2a expression in the rat hippocampus after global brain ischemia, which promotes neuronal tolerance to ischemic brain injury.
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Affiliation(s)
- Wang-sheng Duanmu
- Department of Neurosurgery, General Hospital of Tibet Military Area Command, Lasa, China
| | - Liu Cao
- Department of Neurosurgery, Southwest Hospital of Third Military Medical University, Chongqing, China
| | - Jing-yu Chen
- Department of Neurosurgery, Southwest Hospital of Third Military Medical University, Chongqing, China
| | - Hong-fei Ge
- Department of Neurosurgery, Southwest Hospital of Third Military Medical University, Chongqing, China
| | - Rong Hu
- Department of Neurosurgery, Southwest Hospital of Third Military Medical University, Chongqing, China
| | - Hua Feng
- Department of Neurosurgery, Southwest Hospital of Third Military Medical University, Chongqing, China
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Cairns EA, Baldridge WH, Kelly MEM. The Endocannabinoid System as a Therapeutic Target in Glaucoma. Neural Plast 2016; 2016:9364091. [PMID: 26881140 PMCID: PMC4737462 DOI: 10.1155/2016/9364091] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2015] [Accepted: 11/10/2015] [Indexed: 11/17/2022] Open
Abstract
Glaucoma is an irreversible blinding eye disease which produces progressive retinal ganglion cell (RGC) loss. Intraocular pressure (IOP) is currently the only modifiable risk factor, and lowering IOP results in reduced risk of progression of the disorder. The endocannabinoid system (ECS) has attracted considerable attention as a potential target for the treatment of glaucoma, largely due to the observed IOP lowering effects seen after administration of exogenous cannabinoids. However, recent evidence has suggested that modulation of the ECS may also be neuroprotective. This paper will review the use of cannabinoids in glaucoma, presenting pertinent information regarding the pathophysiology of glaucoma and how alterations in cannabinoid signalling may contribute to glaucoma pathology. Additionally, the mechanisms and potential for the use of cannabinoids and other novel agents that target the endocannabinoid system in the treatment of glaucoma will be discussed.
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Affiliation(s)
- Elizabeth A. Cairns
- Department of Pharmacology, Dalhousie University, Halifax, NS, Canada B3H 4R2
| | - William H. Baldridge
- Department of Medical Neuroscience, Dalhousie University, Halifax, NS, Canada B3H 4R2
- Department of Ophthalmology and Visual Sciences, Dalhousie University, Halifax, NS, Canada B3H 4R2
| | - Melanie E. M. Kelly
- Department of Pharmacology, Dalhousie University, Halifax, NS, Canada B3H 4R2
- Department of Ophthalmology and Visual Sciences, Dalhousie University, Halifax, NS, Canada B3H 4R2
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Expression and Function of the Endocannabinoid System in the Retina and the Visual Brain. Neural Plast 2015; 2016:9247057. [PMID: 26839718 PMCID: PMC4709729 DOI: 10.1155/2016/9247057] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Revised: 09/24/2015] [Accepted: 09/27/2015] [Indexed: 12/16/2022] Open
Abstract
Endocannabinoids are important retrograde modulators of synaptic transmission throughout the nervous system. Cannabinoid receptors are seven transmembrane G-protein coupled receptors favoring Gi/o protein. They are known to play an important role in various processes, including metabolic regulation, craving, pain, anxiety, and immune function. In the last decade, there has been a growing interest for endocannabinoids in the retina and their role in visual processing. The purpose of this review is to characterize the expression and physiological functions of the endocannabinoid system in the visual system, from the retina to the primary visual cortex, with a main interest regarding the retina, which is the best-described area in this system so far. It will show that the endocannabinoid system is widely present in the retina, mostly in the through pathway where it can modulate neurotransmitter release and ion channel activity, although some evidence also indicates possible mechanisms via amacrine, horizontal, and Müller cells. The presence of multiple endocannabinoid ligands, synthesizing and catabolizing enzymes, and receptors highlights various pharmacological targets for novel therapeutic application to retinal diseases.
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Morrone LA, Rombolà L, Corasaniti MT, Bagetta G, Nucci C, Russo R. Natural compounds and retinal ganglion cell neuroprotection. PROGRESS IN BRAIN RESEARCH 2015; 220:257-81. [PMID: 26497795 DOI: 10.1016/bs.pbr.2015.05.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
Glaucoma, the second leading cause of blindness in the world, is a chronic optic neuropathy often associated with increased intraocular pressure and characterized by progressive retinal ganglion cell (RGC) axons degeneration and death leading to typical optic nerve head damage and distinctive visual field defects. Although the pathogenesis of glaucoma is still largely unknown, it is hypothesized that RCGs become damaged through various insults/mechanisms, including ischemia, oxidative stress, excitotoxicity, defective axonal transport, trophic factor withdrawal, and neuroinflammation. In this review, we summarize the potential benefits of several natural compounds for RGCs neuroprotection.
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Affiliation(s)
- Luigi Antonio Morrone
- Department of Pharmacy and Health and Nutritional Sciences, Section of Preclinical and Translational Pharmacology, University of Calabria, Arcavacata di Rende, Italy; University Consortium for Adaptive Disorders and Head Pain (UCHAD), Section of Neuropharmacology of Normal and Pathological Neuronal Plasticity, University of Calabria, Arcavacata di Rende, Italy.
| | - Laura Rombolà
- Department of Pharmacy and Health and Nutritional Sciences, Section of Preclinical and Translational Pharmacology, University of Calabria, Arcavacata di Rende, Italy
| | | | - Giacinto Bagetta
- Department of Pharmacy and Health and Nutritional Sciences, Section of Preclinical and Translational Pharmacology, University of Calabria, Arcavacata di Rende, Italy; University Consortium for Adaptive Disorders and Head Pain (UCHAD), Section of Neuropharmacology of Normal and Pathological Neuronal Plasticity, University of Calabria, Arcavacata di Rende, Italy
| | - Carlo Nucci
- Ophthalmology Unit, Department of Experimental Medicine and Surgery, University of Rome Tor Vergata, Rome, Italy
| | - Rossella Russo
- Department of Pharmacy and Health and Nutritional Sciences, Section of Preclinical and Translational Pharmacology, University of Calabria, Arcavacata di Rende, Italy
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Moris D, Georgopoulos S, Felekouras E, Patsouris E, Theocharis S. The effect of endocannabinoid system in ischemia-reperfusion injury: a friend or a foe? Expert Opin Ther Targets 2015; 19:1261-75. [PMID: 25936364 DOI: 10.1517/14728222.2015.1043268] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
INTRODUCTION In recent years, the endocannabinoid system has emerged as a new therapeutic target in variety of disorders associated with inflammation and tissue injury, including those of the neuronal, liver, renal and cardiovascular system. The aim of the present review is to elucidate the effect of endocannabinoid system on ischemia reperfusion injury (IRI) in different organs and systems. AREAS COVERED The MEDLINE/PubMed database was searched for publications with the medical subject heading Cannabinoids* (CBs), CB receptors*, organ*, ischemia/reperfusion injury*, endocannabinoid* and system*. The initial relevant studies retrieved from the literature were 91 from PubMed. This number was initially limited to 35, after excluding the reviews and studies reporting data for receptors other than cannabinoid. EXPERT OPINION CB2 receptors may play an important compensatory role in controlling tissue inflammation and injury in cells of the neuronal, cardiovascular, liver and renal systems, as well as in infiltrating monocytes/macrophages and leukocytes during various pathological conditions of the systems (atherosclerosis, restenosis, stroke, myocardial infarction, heart, liver and renal failure). These receptors limit inflammation and associated tissue injury. On the basis of preclinical results, pharmacological modulation of CB2 receptors may hold a unique therapeutic potential in stroke, myocardial infarction, atherosclerosis, IRI and liver disease.
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Affiliation(s)
- Demetrios Moris
- National and Kapodistrian University of Athens , Anastasiou Gennadiou 56, 11474, Athens , Greece +30 210 6440590 ;
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Lax P, Esquiva G, Altavilla C, Cuenca N. Neuroprotective effects of the cannabinoid agonist HU210 on retinal degeneration. Exp Eye Res 2014; 120:175-85. [PMID: 24495949 DOI: 10.1016/j.exer.2014.01.019] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2013] [Revised: 01/20/2014] [Accepted: 01/24/2014] [Indexed: 11/18/2022]
Abstract
Cannabinoids have been demonstrated to exert neuroprotective effects on different types of neuronal insults. Here we have addressed the therapeutic potential of the synthetic cannabinoid HU210 on photoreceptor degeneration, synaptic connectivity and functional activity of the retina in the transgenic P23H rat, an animal model for autosomal dominant retinitis pigmentosa (RP). In P23H rats administered with HU210 (100 μg/kg, i.p.) from P24 to P90, ERG recordings showed an amelioration of vision loss, as compared to vehicle-administered animals. Under scotopic conditions, the maximum a-wave amplitudes recorded at P60 and P90 were higher in HU210-treated animals, as compared to the values obtained in untreated animals. The scotopic b-waves were significantly higher in treated animals than in untreated rats at P30, P60 and P90. This attenuation of visual deterioration correlated with a delay in photoreceptor degeneration and the preservation of retinal cytoarchitecture. HU210-treated animals had 40% more photoreceptors than untreated animals. Presynaptic and postsynaptic elements, as well as the synaptic contacts between photoreceptors and bipolar or horizontal cells, were also preserved in HU210-treated P23H rats. These results indicate that HU210 preserves cone and rod structure and function, together with their contacts with postsynaptic neurons, in P23H rats. These data suggest that cannabinoids are potentially useful to delay retinal degeneration in RP patients.
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Affiliation(s)
- Pedro Lax
- Department of Physiology, Genetics and Microbiology, University of Alicante, Alicante, Spain
| | - Gema Esquiva
- Department of Physiology, Genetics and Microbiology, University of Alicante, Alicante, Spain
| | - Cesare Altavilla
- Department of Physiology, Genetics and Microbiology, University of Alicante, Alicante, Spain
| | - Nicolás Cuenca
- Department of Physiology, Genetics and Microbiology, University of Alicante, Alicante, Spain; Institute Ramón Margalef, University of Alicante, Alicante, Spain.
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