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Signorini S, Delledonne A, Pescina S, Bianchera A, Sissa C, Vivero-Lopez M, Alvarez-Lorenzo C, Santi P, Padula C, Nicoli S. A sterilizable platform based on crosslinked xanthan gum for controlled-release of polymeric micelles: Ocular application for the delivery of neuroprotective compounds to the posterior eye segment. Int J Pharm 2024; 657:124141. [PMID: 38677392 DOI: 10.1016/j.ijpharm.2024.124141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2024] [Revised: 04/17/2024] [Accepted: 04/18/2024] [Indexed: 04/29/2024]
Abstract
TPGS (D-α-tocopheryl polyethylene glycol 1000 succinate) polymeric micelles show interesting properties for ocular administration thanks to their solubilization capability, nanometric size and tissue penetration ability. However, micelles formulations are generally characterized by low viscosity, poor adhesion and very short retention time at the administration site. Therefore, the idea behind this work is the preparation and characterization of a crosslinked film based on xanthan gum that contains TPGS micelles and is capable of controlling their release. The system was loaded with melatonin and cyclosporin A, neuroprotective compounds to be delivered to the posterior eye segment. Citric acid and heating at different times and temperatures were exploited as crosslinking approach, giving the possibility to tune swelling, micelles release and drug release. The biocompatibility of the platform was confirmed by HET-CAM assay. Ex vivo studies on isolated porcine ocular tissues, conducted using Franz cells and two-photon microscopy, demonstrated the potential of the xanthan gum-based platform and enlightened micelles penetration mechanism. Finally, the sterilization step was approached, and a process to simultaneously crosslink and sterilize the platform was developed.
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Affiliation(s)
- Sara Signorini
- ADDRes Lab, Department of Food and Drug, University of Parma, Parco Area delle Scienze 27/a, 43124 Parma, Italy.
| | - Andrea Delledonne
- Department of Chemistry, Life Science and Environmental Sustainability, University of Parma, Parco Area delle Scienze 17/a, 43124 Parma, Italy.
| | - Silvia Pescina
- ADDRes Lab, Department of Food and Drug, University of Parma, Parco Area delle Scienze 27/a, 43124 Parma, Italy.
| | - Annalisa Bianchera
- ADDRes Lab, Department of Food and Drug, University of Parma, Parco Area delle Scienze 27/a, 43124 Parma, Italy.
| | - Cristina Sissa
- Department of Chemistry, Life Science and Environmental Sustainability, University of Parma, Parco Area delle Scienze 17/a, 43124 Parma, Italy.
| | - Maria Vivero-Lopez
- Departamento de Farmacología, Farmacia y Tecnología Farmacéutica, I+D Farma (GI-1645), Facultad de Farmacia, Instituto de Materiales (iMATUS) and Health Research Insititute of Santiago de Compostela (IDIS), Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain.
| | - Carmen Alvarez-Lorenzo
- Departamento de Farmacología, Farmacia y Tecnología Farmacéutica, I+D Farma (GI-1645), Facultad de Farmacia, Instituto de Materiales (iMATUS) and Health Research Insititute of Santiago de Compostela (IDIS), Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain.
| | - Patrizia Santi
- ADDRes Lab, Department of Food and Drug, University of Parma, Parco Area delle Scienze 27/a, 43124 Parma, Italy.
| | - Cristina Padula
- ADDRes Lab, Department of Food and Drug, University of Parma, Parco Area delle Scienze 27/a, 43124 Parma, Italy.
| | - Sara Nicoli
- ADDRes Lab, Department of Food and Drug, University of Parma, Parco Area delle Scienze 27/a, 43124 Parma, Italy.
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Pastor-Idoate S, Mateos-Olivares M, Sobas EM, Marcos M, Toribio A, Pastor JC, Usategui Martín R. Short-Wavelength Light-Blocking Filters and Oral Melatonin Administration in Patients With Retinitis Pigmentosa: Protocol for a Randomized Controlled Trial. JMIR Res Protoc 2023; 12:e49196. [PMID: 37971796 PMCID: PMC10690531 DOI: 10.2196/49196] [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: 05/21/2023] [Revised: 09/27/2023] [Accepted: 10/10/2023] [Indexed: 11/19/2023] Open
Abstract
BACKGROUND The medical community is beginning to recognize that retinitis pigmentosa (RP), due to its disabling progression, eventually leads to a reduction in the patient´s quality of life, a direct economic impact, and an increase in the burden on the health care system. There is no curative treatment for the origin of the disease, and most of the current interventions fail in reducing the associated negative psychological states, such as anxiety and depression, which lead to increased variability of vision and pose a continuous threat to the patient's independence. OBJECTIVE The aim of this study is to assess the effect of oral melatonin (OM) administration alone and combined with short-wavelength light (SWL)-blocking filters on patients with RP and test their effectiveness in improving the level of stress and sleep problems in many of these patients. METHODS We have developed a low-cost therapy protocol for patients with RP with sleep disorders and negative psychological stress. Patients will be randomized to receive a combined intervention with SWL-blocking filters and OM, SWL-blocking filters alone, or OM alone. There will also be a nonintervention arm as a control group. This study will be conducted across 2 retinal units in patients with RP with sleep disorders and high perceived stress and anxiety score reports. Patients will be assessed in the preintervention period, weekly during the 4 weeks of intervention, and then at 6 months postintervention. The primary outcomes are the differences in changes from baseline to postintervention in hormone release (α-amylase, cortisol, and melatonin) and sleep quality, as measured with the visual analog scale. Secondary outcome measures include clinical macular changes, as measured with optical coherence tomography and optical coherence tomography angiography; retinal function, as measured using the visual field and best-corrected visual acuity; sleep data collected from personal wearables; and several patient-reported variables, such as self-recorded sleep diaries, quality of life, perceived stress, and functional status. RESULTS This project is still a study protocol and has not yet started. Bibliographic research for information for its justification began in 2020, and this working group is currently seeking start-up funding. As soon as we have the necessary means, we will proceed with the registration and organization prior to the preliminary phase. CONCLUSIONS In this feasibility randomized clinical controlled trial, we will compare the effects of SWL blocking alone, administration of OM alone, and a combined intervention with both in patients with RP. We present this study so that it may be replicated and incorporated into future studies at other institutions, as well as applied to additional inherited retinal dystrophies. The goal of presenting this protocol is to aid recent efforts in reducing the impact of sleeping disorders and other psychological disorders on the quality of life in patients with RP and recovering their self-autonomy. In addition, the results of this study will represent a significant step toward developing a novel low-cost therapy for patients with RP and validating a novel therapeutic target. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID) PRR1-10.2196/49196.
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Affiliation(s)
- Salvador Pastor-Idoate
- Institute of Applied Ophthalmobiology, University of Valladolid, Valladolid, Spain
- Department of Ophthalmology, Clinical University Hospital of Valladolid, Valladolid, Spain
- Networks of Cooperative Research oriented to Health Results, National Institute of Health Carlos III, Madrid, Spain
- European Reference Network dedicated to Rare Eye Diseases, Valladolid, Spain
| | - Milagros Mateos-Olivares
- Department of Ophthalmology, Clinical University Hospital of Valladolid, Valladolid, Spain
- Department of Ophthalmology, Clinical University Hospital of Caceres, Caceres, Spain
| | - Eva María Sobas
- Institute of Applied Ophthalmobiology, University of Valladolid, Valladolid, Spain
- Nursing School, University of Valladolid, Valladolid, Spain
| | - Miguel Marcos
- Department of Internal Medicine, University Hospital of Salamanca, Salamanca, Spain
- Institute of Biomedical Research of Salamanca, University of Salamanca, Salamanca, Spain
| | - Alfredo Toribio
- Federation of Associations of Hereditary Retinal Dystrophies in Spain, Valladolid, Spain
| | - José Carlos Pastor
- Institute of Applied Ophthalmobiology, University of Valladolid, Valladolid, Spain
- Networks of Cooperative Research oriented to Health Results, National Institute of Health Carlos III, Madrid, Spain
- European Reference Network dedicated to Rare Eye Diseases, Valladolid, Spain
| | - Ricardo Usategui Martín
- Institute of Applied Ophthalmobiology, University of Valladolid, Valladolid, Spain
- Department of Cellular Biology, Faculty of Medicine, University of Valladolid, Valladolid, Spain
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Ashfaq R, Rasul A, Asghar S, Kovács A, Berkó S, Budai-Szűcs M. Lipid Nanoparticles: An Effective Tool to Improve the Bioavailability of Nutraceuticals. Int J Mol Sci 2023; 24:15764. [PMID: 37958750 PMCID: PMC10648376 DOI: 10.3390/ijms242115764] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2023] [Revised: 10/26/2023] [Accepted: 10/28/2023] [Indexed: 11/15/2023] Open
Abstract
Nano-range bioactive colloidal carrier systems are envisaged to overcome the challenges associated with treatments of numerous diseases. Lipid nanoparticles (LNPs), one of the extensively investigated drug delivery systems, not only improve pharmacokinetic parameters, transportation, and chemical stability of encapsulated compounds but also provide efficient targeting and reduce the risk of toxicity. Over the last decades, nature-derived polyphenols, vitamins, antioxidants, dietary supplements, and herbs have received more attention due to their remarkable biological and pharmacological health and medical benefits. However, their poor aqueous solubility, compromised stability, insufficient absorption, and accelerated elimination impede research in the nutraceutical sector. Owing to the possibilities offered by various LNPs, their ability to accommodate both hydrophilic and hydrophobic molecules and the availability of various preparation methods suitable for sensitive molecules, loading natural fragile molecules into LNPs offers a promising solution. The primary objective of this work is to explore the synergy between nature and nanotechnology, encompassing a wide range of research aimed at encapsulating natural therapeutic molecules within LNPs.
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Affiliation(s)
- Rabia Ashfaq
- Institute of Pharmaceutical Technology and Regulatory Affairs, Faculty of Pharmacy, University of Szeged, Eötvös u. 6, H-6720 Szeged, Hungary; (R.A.)
| | - Akhtar Rasul
- Faculty of Pharmaceutical Sciences, Government College University Faisalabad, Faisalabad 38000, Pakistan; (A.R.); (S.A.)
| | - Sajid Asghar
- Faculty of Pharmaceutical Sciences, Government College University Faisalabad, Faisalabad 38000, Pakistan; (A.R.); (S.A.)
| | - Anita Kovács
- Institute of Pharmaceutical Technology and Regulatory Affairs, Faculty of Pharmacy, University of Szeged, Eötvös u. 6, H-6720 Szeged, Hungary; (R.A.)
| | - Szilvia Berkó
- Institute of Pharmaceutical Technology and Regulatory Affairs, Faculty of Pharmacy, University of Szeged, Eötvös u. 6, H-6720 Szeged, Hungary; (R.A.)
| | - Mária Budai-Szűcs
- Institute of Pharmaceutical Technology and Regulatory Affairs, Faculty of Pharmacy, University of Szeged, Eötvös u. 6, H-6720 Szeged, Hungary; (R.A.)
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Morsali S, Sabahi Z, Kakaei J, Hakimzadeh Z, Hamidi S, Gholipour-Khalili E, Sanaie S, Talebi M, Naseri A. Clinical efficacy and safety of melatonin supplementation in multiple sclerosis: a systematic review. Inflammopharmacology 2023; 31:2213-2220. [PMID: 37429996 DOI: 10.1007/s10787-023-01271-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Accepted: 06/10/2023] [Indexed: 07/12/2023]
Abstract
BACKGROUND Melatonin is a neurohormone secreted predominantly by the pineal gland that is demonstrated to be associated with the pathogenesis of multiple sclerosis (MS). This research desires to evaluate the tolerability and beneficial effects of exogenous melatonin supplementations in patients with MS. METHODS This study was executed following the PRISMA 2020 statement. Both observational and interventional studies which reported the clinical effectiveness and/or safety of melatonin supplementation in patients with MS were included in this systematic review. Ovid, PubMed, Scopus, Embase, and Web of Science databases were searched and the risk of bias in included studies was assessed using the Joanna Briggs Institute (JBI) critical appraisal tools based on study design. RESULTS Out of 1304 results of database searches, finally, 14 articles, including 7 randomized controlled trials (RCTs), 6 case-control studies, and one quasi-experimental study, were included based on the full-text review. Included phenotypes of MS were mostly relapsing-remitting MS (RRMS) (in 11 studies); it was secondary progressive MS (SPMS) in only one study, and two other studies had a mixture of the different phenotypes. The course of treatment with melatonin supplementation was between 2 weeks and 12 months. There were no substantial safety issues. Although melatonin was associated with enhanced oxidative stress and inflammation status, concerning the clinical benefits, limited studies suggested improvements in sleep conditions, cognitive outcomes, and fatigue in MS. DISCUSSION There are insufficient data to support the regular melatonin prescription in MS. Limitations such as the small number of included studies, the diversity of the dosage, route, and duration of melatonin administration, and the diversity of assessment tests lead to unconvincing findings in this study. There is a need for future studies to achieve a comprehensive judgment on this subject.
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Affiliation(s)
- Soroush Morsali
- Student Research Committee, Tabriz University of Medical Sciences, Golgasht Street, Tabriz, 5166/15731, East Azerbaijan, Iran
| | - Zahra Sabahi
- Research Center for Evidence-Based Medicine, Iranian EBM Centre: A Joanna Briggs Institute (JBI) Center of Excellence, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Javad Kakaei
- Zanjan Branch (IAUZ), Islamic Azad University, Zanjan, Iran
| | - Zahra Hakimzadeh
- Neurosciences Research Center (NSRC), Tabriz University of Medical Sciences, Tabriz, 5166/15731, Iran
| | - Sana Hamidi
- Student Research Committee, Tabriz University of Medical Sciences, Golgasht Street, Tabriz, 5166/15731, East Azerbaijan, Iran
| | | | - Sarvin Sanaie
- Neurosciences Research Center (NSRC), Tabriz University of Medical Sciences, Tabriz, 5166/15731, Iran
| | - Mahnaz Talebi
- Neurosciences Research Center (NSRC), Tabriz University of Medical Sciences, Tabriz, 5166/15731, Iran.
| | - Amirreza Naseri
- Student Research Committee, Tabriz University of Medical Sciences, Golgasht Street, Tabriz, 5166/15731, East Azerbaijan, Iran.
- Research Center for Evidence-Based Medicine, Iranian EBM Centre: A Joanna Briggs Institute (JBI) Center of Excellence, Tabriz University of Medical Sciences, Tabriz, Iran.
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Rasaei N, Samadi M, Khadem A, Badrooj N, Hassan Zadeh M, Ghaffarian-Ensaf R, Gholami F, Mirzaei K. The association between cholesterol/saturated fat index (CSI) and quality of sleep, and circadian rhythm among overweight and obese women: a cross-sectional study. JOURNAL OF HEALTH, POPULATION, AND NUTRITION 2023; 42:75. [PMID: 37501196 PMCID: PMC10375646 DOI: 10.1186/s41043-023-00414-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Accepted: 07/09/2023] [Indexed: 07/29/2023]
Abstract
BACKGROUND The decline in sleep quality is one of the main public health problems affecting the global population. Some studies have shown that a high-fat diet may be linked to changes in circadian rhythm and sleep quality. The cholesterol/saturated fatty acid index (CSI) determines the amount of cholesterol and saturated fatty acid (SFA) in people's dietary patterns and can affect the quality of sleep and circadian rhythm. However, to date, no studies have investigated the effect of this index on these two variables. Therefore, our aim was to investigate the relationship between CSI on circadian rhythm and sleep quality in obese and overweight women. METHOD This cross-sectional study included 378 adult women who were obese or overweight. Using accepted techniques, anthropometric measurements, blood pressure readings, and biochemical variables were evaluated. A validated and trustworthy semi-quantitative food frequency questionnaire (FFQ 147 items) was used to gauge dietary intake. The CSI was measured to find out how much cholesterol and saturated fats were in the diet. Additionally, to assess circadian rhythm and sleep quality, respectively, the valid morning-evening questionnaire (MEQ) and Pittsburgh sleep quality index (PSQI) questionnaires were utilized. RESULT The results of the multinomial logistic regression model of our analysis showed that a significant association was observed between circadian rhythm status with CSI score, and participants with one higher unit of CSI had a 7.3% more chance of being in the eveningness group than being in morningness category in the crude model (OR: 1.07; 95% CI 1.00, 1.14; P = 0.026). This association remains marginally significant when adjusting for age, energy intake, BMI, job status, thyroid, and smoking status (OR = 1.08; 95% CI 1.00, 1.16; P = 0.051). The binary logistic regression model showed that after controlling for potentially confounding variables, there was no significant association between sleep quality with CSI score, however, those with one higher unit of CSI had 1.6% more chance of having sleep problems (OR: 1.01; 95% CI 0.96, 1.06; P = 0.503). CONCLUSION Our results indicated a direct marginally significant association between CSI with evening type in overweight and obese women. Future studies are needed to clarify the precise link between circadian rhythm and sleep behavior with fatty acid quality index.
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Affiliation(s)
- Niloufar Rasaei
- Department of Community Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences (TUMS), P.O. Box: 14155-6117, Tehran, Iran
| | - Mahsa Samadi
- Department of Community Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences (TUMS), P.O. Box: 14155-6117, Tehran, Iran
| | - Alireza Khadem
- Department of Nutrition, Science and Research Branch, Islamic Azad University, Tehran, Iran
| | - Negin Badrooj
- Department of Community Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences (TUMS), P.O. Box: 14155-6117, Tehran, Iran
| | - Mohadeseh Hassan Zadeh
- Department of Nutrition, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | | | - Fatemeh Gholami
- Department of Community Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences (TUMS), P.O. Box: 14155-6117, Tehran, Iran
| | - Khadijeh Mirzaei
- Department of Community Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences (TUMS), P.O. Box: 14155-6117, Tehran, Iran.
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Li KL, Shan SW, Lin FY, Ling CY, Wong NW, Li HL, Han W, To CH, Do CW. Regulation of Aqueous Humor Secretion by Melatonin in Porcine Ciliary Epithelium. Int J Mol Sci 2023; 24:5789. [PMID: 36982863 PMCID: PMC10051954 DOI: 10.3390/ijms24065789] [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: 02/08/2023] [Revised: 03/10/2023] [Accepted: 03/16/2023] [Indexed: 03/30/2023] Open
Abstract
Secretion of melatonin, a natural hormone whose receptors are present in the ciliary epithelium, displays diurnal variation in the aqueous humor (AH), potentially contributing to the regulation of intraocular pressure. This study aimed to determine the effects of melatonin on AH secretion in porcine ciliary epithelium. The addition of 100 µM melatonin to both sides of the epithelium significantly increased the short-circuit current (Isc) by ~40%. Stromal administration alone had no effect on the Isc, but aqueous application triggered a 40% increase in Isc, similar to that of bilateral application without additive effect. Pre-treatment with niflumic acid abolished melatonin-induced Isc stimulation. More importantly, melatonin stimulated the fluid secretion across the intact ciliary epithelium by ~80% and elicited a sustained increase (~50-60%) in gap junctional permeability between pigmented ciliary epithelial (PE) cells and non-pigmented ciliary epithelial (NPE) cells. The expression of MT3 receptor was found to be >10-fold higher than that of MT1 and MT2 in porcine ciliary epithelium. Aqueous pre-treatment with MT1/MT2 antagonist luzindole failed to inhibit the melatonin-induced Isc response, while MT3 antagonist prazosin pre-treatment abolished the Isc stimulation. We conclude that melatonin facilitates Cl- and fluid movement from PE to NPE cells, thereby stimulating AH secretion via NPE-cell MT3 receptors.
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Affiliation(s)
- Ka-Lok Li
- School of Optometry, The Hong Kong Polytechnic University, Hong Kong, China
| | - Sze-Wan Shan
- School of Optometry, The Hong Kong Polytechnic University, Hong Kong, China
- Centre for Eye and Vision Research (CEVR), 17W Hong Kong Science Park, Hong Kong, China
- Research Centre for SHARP Vision (RCSV), The Hong Kong Polytechnic University, Hong Kong, China
| | - Fang-Yu Lin
- School of Optometry, The Hong Kong Polytechnic University, Hong Kong, China
- Department of Ophthalmology, Zhejiang University, Hangzhou 310027, China
- Department of Ophthalmology, Emory University, Atlanta, GA 30322, USA
| | - Choi-Ying Ling
- School of Optometry, The Hong Kong Polytechnic University, Hong Kong, China
| | - Nga-Wai Wong
- School of Optometry, The Hong Kong Polytechnic University, Hong Kong, China
| | - Hoi-Lam Li
- School of Optometry, The Hong Kong Polytechnic University, Hong Kong, China
- Centre for Eye and Vision Research (CEVR), 17W Hong Kong Science Park, Hong Kong, China
| | - Wei Han
- Department of Ophthalmology, Zhejiang University, Hangzhou 310027, China
| | - Chi-Ho To
- School of Optometry, The Hong Kong Polytechnic University, Hong Kong, China
- Centre for Eye and Vision Research (CEVR), 17W Hong Kong Science Park, Hong Kong, China
- Research Centre for SHARP Vision (RCSV), The Hong Kong Polytechnic University, Hong Kong, China
| | - Chi-Wai Do
- School of Optometry, The Hong Kong Polytechnic University, Hong Kong, China
- Centre for Eye and Vision Research (CEVR), 17W Hong Kong Science Park, Hong Kong, China
- Research Centre for SHARP Vision (RCSV), The Hong Kong Polytechnic University, Hong Kong, China
- Research Institute of Smart Ageing (RISA), The Hong Kong Polytechnic University, Hong Kong, China
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Sciriha GG, Sultana J, Borg J. Identifying and categorizing compounds that reduce corneal transforming growth factor beta induced protein levels: a scoping review. Expert Rev Clin Pharmacol 2022; 15:1423-1442. [PMID: 36308770 DOI: 10.1080/17512433.2022.2142560] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
INTRODUCTION Transforming growth factor beta induced (TGFBI) gene mutations have been reported as the cause of a group of genetically inherited, visually debilitating, corneal dystrophies (CD). A scoping literature review to identify and categorize compounds that inhibit corneal TGFBI expression and/or promote TGFBIp degradation was performed. Emphasis was given to their potential to be used as a cost-effective approach via drug repurposing. AREAS COVERED We performed a thorough search of original peer-reviewed literature using electronic bibliographic databases and selected articles according to a set of criteria. The total number of articles retrieved from the search terms applied to the databases was 2344. The number of relevant full-text articles included added up to 19. We identified 16 compounds that can theoretically reduce the levels of mutant TGFBIp in human corneal cells. EXPERT OPINION Currently, the only temporary treatments available for this condition are lubricant drops and surgery. Here, we explored the crosstalk between cascades that regulate TGFBI expression and identified compounds that target these pathways. Compounds that inhibit DNA synthesis and function, increase elimination of TGFBIp or bind to mutant TGFBIp were also explored with the aim of highlighting promising compounds that can be used in future cost-effective drug-repurposing studies.
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Affiliation(s)
| | - Janet Sultana
- College of Medicine and Health, University of Exeter, Exeter UK
| | - Joseph Borg
- Department of Applied Biomedical Science, Faculty of Health Sciences, University of Malta, Msida, Malta
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Mousavi SA, Mirzababaei A, Shiraseb F, Clark CCT, Mirzaei K. The association between modified Nordic diet with sleep quality and circadian rhythm in overweight and obese woman: a cross-sectional study. Eat Weight Disord 2022; 27:1835-1845. [PMID: 34757589 DOI: 10.1007/s40519-021-01327-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Accepted: 10/20/2021] [Indexed: 12/24/2022] Open
Abstract
OBJECTIVE Previous studies have shown an association between diet quality and sleep quality. The objective of this study was to investigate the association between modified Nordic diet with sleep quality and circadian rhythm in overweight and obese woman. METHODS We enrolled 399 overweight and obese women (body mass index (BMI): 25-40 kg/m2), aged 18-48 years, in this cross-sectional study. For each participant, anthropometric measurements, biochemical tests, and food intake were evaluated. Sleep quality and circadian rhythm was measured by Pittsburgh Sleep Quality Index (PSQI) and morning-evening questionnaire (MEQ) questionnaire. Modified Nordic diet score was measured using a validated 147-item food frequency questionnaire (FFQ). RESULTS Overall, 51.7% of the subjects were good sleepers (the Pittsburgh Sleep Quality Index (PSQI) < 5) while 48.3% were poor sleepers (PSQI ≥ 5). Moreover, participants were divided into five groups of MEQ, namely, completely morning 8 (2.4%), rarely morning 82 (24.8%), normal 196 (59.2%), rarely evening 43 (13%), and completely evening 2 (0.6%). After controlling for confounders, there was a significant association between poor sleep quality and the modified Nordic diet (OR = 0.80, %95 CI = 0.66-0.98, P = 0.01). Moreover, a significant positive association was observed between the completely morning and modified Nordic diet (OR = 1.80, %95 CI = 0.54-6.00, P = 0.03), in addition to a significant inverse association between the completely evening type and modified Nordic diet (OR = 0.16, %95 CI = 0.002-5.41, P = 0.02). CONCLUSIONS The present study indicated that higher adherence to a modified Nordic diet reduces poor sleep quality. Also, the completely morning type was associated with higher adherence to a modified Nordic diet, and completely evening type was associated with lower adherence to a modified Nordic diet. LEVELS OF EVIDENCE Level IV, evidence obtained from multiple time series analysis.
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Affiliation(s)
- Seyed Ahmad Mousavi
- Department of Nutrition Science, Science and Research Branch, Faculty of Medical Sciences and Technologies, Islamic Azad University, Tehran, Iran
| | - Atieh Mirzababaei
- Department of Community Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences (TUMS), P.O. Box: 14155-6117, Tehran, Iran
| | - Farideh Shiraseb
- Department of Community Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences (TUMS), P.O. Box: 14155-6117, Tehran, Iran
| | - Cain C T Clark
- Centre for Intelligent Healthcare, Coventry University, Coventry, CV1 5FB, UK
| | - Khadijeh Mirzaei
- Department of Community Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences (TUMS), P.O. Box: 14155-6117, Tehran, Iran.
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Bessone CDV, Martinez SM, Luna JD, Marquez MA, Ramírez ML, Allemandi DA, Carpentieri ÁR, Quinteros DA. Neuroprotective effect of melatonin loaded in ethylcellulose nanoparticles applied topically in a retinal degeneration model in rabbits. Exp Eye Res 2020; 200:108222. [PMID: 32898513 DOI: 10.1016/j.exer.2020.108222] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 08/12/2020] [Accepted: 09/03/2020] [Indexed: 12/18/2022]
Abstract
We are reporting for the first time the synthesis and application of an innovative nanometric system for the controlled topic release of melatonin in the retina. The ethylcellulose nanocapsules were characterized by diverse physicochemical techniques (scanning electron microscopy, zeta potential, hydrodynamic diameters) and an in vitro release study was done. A complete ex vivo and in vivo trans-corneal permeation and an irritation study were carried out with the new formulations in albino rabbits, to which a retinal degenerative model was induced. The results obtained demonstrate that the in vitro release of melatonin (1 mg/mL and 2 mg/mL) transported by nanocapsules is slower when compared to a solution of melatonin. Greater penetration of melatonin through the cornea was demonstrated by ex vivo and in vivo tests. This can be attributable to an enhanced neuroprotective effect of melatonin on retinal ganglion cells when it is included in ethylcellulose nanocapsules compared to a solution of melatonin. These outstanding findings add promising new perspectives to current knowledge about administrations using nano-technological tools in the treatment of neurodegenerative diseases at the ocular level.
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Affiliation(s)
- Carolina D V Bessone
- Unidad de Investigación y Desarrollo en Tecnología Farmacéutica (UNITEFA), CONICET and Departamento de Ciencias Farmacéuticas, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria, 5000, Córdoba, Argentina
| | - Sofia M Martinez
- Unidad de Investigación y Desarrollo en Tecnología Farmacéutica (UNITEFA), CONICET and Departamento de Ciencias Farmacéuticas, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria, 5000, Córdoba, Argentina
| | - José D Luna
- Área de Cirugía de Vítreo y Retina, Centro Privado de Ojos Romagosa S.A. and Fundación VER, 5000, Córdoba, Argentina
| | - Marilyn A Marquez
- Área de Cirugía de Vítreo y Retina, Centro Privado de Ojos Romagosa S.A. and Fundación VER, 5000, Córdoba, Argentina
| | - María L Ramírez
- Unidad de Investigación y Desarrollo en Tecnología Farmacéutica (UNITEFA), CONICET and Departamento de Ciencias Farmacéuticas, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria, 5000, Córdoba, Argentina
| | - Daniel A Allemandi
- Unidad de Investigación y Desarrollo en Tecnología Farmacéutica (UNITEFA), CONICET and Departamento de Ciencias Farmacéuticas, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria, 5000, Córdoba, Argentina
| | - Ágata R Carpentieri
- Instituto de Investigación en Ciencias de la Salud (INICSA), CONICET, Universidad Nacional de Córdoba and Cátedra B de Química Biológica, Facultad de Odontología, Universidad Nacional de Córdoba, Ciudad Universitaria, 5000, Córdoba, Argentina
| | - Daniela A Quinteros
- Unidad de Investigación y Desarrollo en Tecnología Farmacéutica (UNITEFA), CONICET and Departamento de Ciencias Farmacéuticas, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria, 5000, Córdoba, Argentina.
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10
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Current Medical Therapy and Future Trends in the Management of Glaucoma Treatment. J Ophthalmol 2020; 2020:6138132. [PMID: 32774906 PMCID: PMC7391108 DOI: 10.1155/2020/6138132] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Accepted: 06/29/2020] [Indexed: 01/02/2023] Open
Abstract
Glaucoma is a neurodegenerative disease characterized by progressive loss of retinal ganglion cells and their axons. Lowering of intraocular pressure (IOP) is currently the only proven treatment strategy for glaucoma. However, some patients show progressive loss of visual field and quality of life despite controlled IOP which indicates that other factors are implicated in glaucoma. Therefore, approaches that could prevent or decrease the rate of progression and do not rely on IOP lowering have gained much attention. Effective neuroprotection has been reported in animal models of glaucoma, but till now, no neuroprotective agents have been clinically approved. The present update provides an overview of currently available IOP-lowering medications. Moreover, potential new treatment targets for IOP-lowering and neuroprotective therapy are discussed. Finally, future trends in glaucoma therapy are addressed, including sustained drug delivery systems and progress toward personalized medicine.
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11
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Betti L, Palego L, Demontis GC, Miraglia F, Giannaccini G. Hydroxyindole- O-methyltransferase (HIOMT) activity in the retina of melatonin-proficient mice. Heliyon 2019; 5:e02417. [PMID: 31687544 PMCID: PMC6819757 DOI: 10.1016/j.heliyon.2019.e02417] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Revised: 07/19/2019] [Accepted: 09/02/2019] [Indexed: 01/02/2023] Open
Abstract
Numerous pieces of evidence support the expression by the mammalian retina of Hydroxyindole-O-methyltransferase (HIOMT, EC 2.1.1.4), the enzyme directly responsible for the biosynthesis of the pineal chronobiotic hormone melatonin (MLT). However, conflicting results obtained so far by enzyme-kinetic and immune-detection techniques still make HIOMT presence and relevance in the eye a matter of debate. This work aimed at evaluating unambiguously HIOMT activity in the mouse retina, a valuable model for studying the effects of MLT variations on ocular pathophysiology. Since laboratory mouse strains can bear genetic polymorphisms yielding defective enzymes of MLT biosynthesis, retinas and control pineal glands used in this study were obtained in a MLT-proficient crossing of A/J mice, the A/J/C57BL/10 strain. To improve the radiochemical reference assay, we tested different homogenization procedures coupled with HPLC detection. Concomitantly, we quantified MLT, and its precursor N-acetyl-serotonin (NAS) by HPLC coupled to electrochemical detection in retinas isolated from either light- or dark-adapted mice. Results showed that the standard radio-chemical assay was successful for pineal HIOMT only, whereas specific homogenization buffers and HPLC were required to detect retinal activity, presumably due to interfering methyl-transferases inhibited by NAS. Under present conditions, retinal HIOMT Vmax accounted for by ≈ 40 fmol/h/mg protein, 2.6-hundreds-fold lower than the pineal counterpart, displaying equivalent KMs (≈10 μM). Moreover, NAS and MLT rapidly decreased in light-exposed isolated retinas, corroborating light-sensitive in-situ MLT formation. Conclusively, we measured mouse retinal HIOMT kinetics under basal conditions, a useful result to elucidate the regulatory patterns, the possible impact on eye health, and therapeutic approaches related to this enzyme.
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Affiliation(s)
- Laura Betti
- Department of Pharmacy, Via Bonanno 6, University of Pisa, 56126 Pisa, Italy
- Corresponding author.
| | - Lionella Palego
- Department of Clinical and Experimental Medicine, Via Savi 10, University of Pisa, 56126 Pisa, Italy
- Corresponding author.
| | - Gian Carlo Demontis
- Department of Pharmacy, Via Bonanno 6, University of Pisa, 56126 Pisa, Italy
| | - Fabiana Miraglia
- Department of Pharmacy, Via Bonanno 6, University of Pisa, 56126 Pisa, Italy
| | - Gino Giannaccini
- Department of Pharmacy, Via Bonanno 6, University of Pisa, 56126 Pisa, Italy
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Visser HE, Dees DD, Millichamp NJ, Vallone LV, Scott EM. Effect of orally administered melatonin on intraocular pressure of ophthalmologically normal dogs. Am J Vet Res 2019; 80:410-415. [PMID: 30919670 DOI: 10.2460/ajvr.80.4.410] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To determine the effect of orally administered melatonin on the intraocular pressure (IOP) of ophthalmologically normal dogs. ANIMALS 20 ophthalmologically normal dogs (40 eyes). PROCEDURES In a randomized crossover study, each dog received a 7-day regimen of melatonin (0.1 to 0.2 mg/kg, PO, q 12 h) and a placebo (150 mg of lactose powder in a capsule, PO, q 12 h), with a 7-day washout period between treatment regimens. Rebound tonometry was used to measure the IOP in both eyes of each dog 5 times at 2-hour intervals on days 0 (before administration of the first dose), 2, 4, and 7 (after administration of the last dose) of each treatment period. Repeated-measures ANOVA was used to evaluate the effects of treatment, day, and IOP measurement time within day on IOP. RESULTS Intraocular pressure was not significantly associated with treatment but was associated with day and the interaction between day and IOP measurement time within day. The mean ± SD IOP was 14.26 ± 2.95 and 14.34 ± 2.69 mm Hg for the melatonin and placebo regimens, respectively. Within each treatment period, the mean IOP tended to decrease from day 0 to 7 as well as within each day, which was attributed to the dogs becoming acclimated to the study protocol and natural diurnal variations in IOP. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that oral administration of melatonin (0.1 to 0.2 mg/kg, q 12 h for 7 d) did not significantly affect the IOP of ophthalmologically normal dogs.
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13
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Arranz-Romera A, Davis B, Bravo-Osuna I, Esteban-Pérez S, Molina-Martínez I, Shamsher E, Ravindran N, Guo L, Cordeiro M, Herrero-Vanrell R. Simultaneous co-delivery of neuroprotective drugs from multi-loaded PLGA microspheres for the treatment of glaucoma. J Control Release 2019; 297:26-38. [DOI: 10.1016/j.jconrel.2019.01.012] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Revised: 12/20/2018] [Accepted: 01/13/2019] [Indexed: 01/05/2023]
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Gubin DG, Malishevskaya ТN, Astakhov YS, Astakhov SY, Cornelissen G, Kuznetsov VA, Weinert D. Progressive retinal ganglion cell loss in primary open-angle glaucoma is associated with temperature circadian rhythm phase delay and compromised sleep. Chronobiol Int 2019; 36:564-577. [PMID: 30663431 DOI: 10.1080/07420528.2019.1566741] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Advanced primary open-angle glaucoma (POAG) is characterized by progressive retinal ganglion cell complex (RGCC) damage that may cause subsequent disruption of the circadian rhythms. Therefore, we evaluated circadian body temperature (BT) rhythm and sleep characteristics of 115 individuals (38 men and 77 women) diagnosed with POAG. GLV (global loss volume; %), a measure of RGCC damage, was estimated by high-definition optical coherence tomography, and RGC functional ability was assessed by pattern electroretinogram amplitude (PERGA). Depending on dynamics of POAG progression criteria, two groups were formed that were distinctively different in GLV: Stable POAG group (S-POAG; GLV = 5.95 ± 1.84, n = 65) and Progressive POAG group (P-POAG; GLV = 24.27 ± 5.09, n = 50). S-POAG and P-POAG groups were not different in mean age (67.61 ± 7.56 versus 69.98 ± 8.15) or body mass index (24.66 ± 3.03 versus 24.77 ± 2.90). All subjects performed 21 around-the-clock BT self-measurements during a 72-h period and kept activity/sleep diaries. Results showed pronounced disruption of circadian physiology in POAG and its progression with increasing severity of the disease. The daily mean of BT was unusually low, compared to age-matched controls. Moreover, our results revealed distinctive features of BT circadian rhythm alterations in POAG development and POAG progression. S-POAG is associated with lowered BT circadian rhythm robustness and inter-daily phase stability compared to controls. In the P-POAG group, the mean phase of the circadian BT rhythm was delayed by about 5 h and phases were highly scattered among individual patients, which led to reduced group mean amplitude. Circadian amplitudes of individuals were not different between the groups. Altogether, these results suggest that the body clock still works in POAG patients, but its entrainment to the 24-h environment is compromised. Probably because of the internal desynchronization, bedtime is delayed, and sleep duration is accordingly shortened by about 55 min in P-POAG compared to S-POAG patients. In the entire POAG cohort (both groups), later sleep phase and shorter mean sleep duration correlate with the delayed BT phase (r = 0.215; p = 0.021 and r = 0.322; p = 0.0004, respectively). An RGCC GLV of 15% apparently constitutes a threshold above which a delay of the circadian BT rhythm and a shortening of sleep duration occur.
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Affiliation(s)
- D G Gubin
- a Department of Biology , Medical University , Tyumen , Russia.,b Tyumen Cardiology Research Center , Tomsk National Research Medical Center, Russian Academy of Science , Tomsk , Russia
| | - Т N Malishevskaya
- c Department of Organization of Medical Care , State Autonomous Health Care Institution Tyumen Regional Ophthalmological Dispensary , Tyumen , Russia.,d Department of Ophthalmology and Optometry , West-Siberian Institute of Postgraduate Medical Education , Tyumen , Russia
| | - Y S Astakhov
- e Department of Ophthalmology , Pavlov First Saint Petersburg State Medical University , St. Petersburg , Russia
| | - S Y Astakhov
- e Department of Ophthalmology , Pavlov First Saint Petersburg State Medical University , St. Petersburg , Russia
| | - G Cornelissen
- f Halberg Chronobiology Center , University of Minnesota , Minneapolis , MN , USA
| | - V A Kuznetsov
- b Tyumen Cardiology Research Center , Tomsk National Research Medical Center, Russian Academy of Science , Tomsk , Russia
| | - D Weinert
- g Institute of Biology/Zoology , Martin Luther University , Halle-Wittenberg , Germany
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Pinazo-Durán MD, Shoaie-Nia K, Zanón-Moreno V, Sanz-González SM, Benítez del Castillo J, García-Medina JJ. Strategies to Reduce Oxidative Stress in Glaucoma Patients. Curr Neuropharmacol 2018; 16:903-918. [PMID: 28677495 PMCID: PMC6120109 DOI: 10.2174/1570159x15666170705101910] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Revised: 05/17/2017] [Accepted: 06/22/2017] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Primary open-angle glaucoma (POAG) is a multifactorial pathology involving a variety of pathogenic mechanisms, including oxidative/nitrosative stress. This latter is the consequence of the imbalance between excessive formation and insufficient protection against reactive oxygen/nitrogen species. OBJECTIVE Our main goal is to gather molecular information to better managing pathologic variants that may determine the individual susceptibility to oxidative/nitrosative stress (OS/NS) and POAG. METHOD An extensive search of the scientific literature was conducted using PUBMED, the Web of Science, the Cochrane Library, and other references on the topic of POAG and OS/NS from human and animal model studies published between 2010 and 2017. Finally, 152 works containing relevant information that may help understanding the role of antioxidants, essential fatty acids, natural compounds and other similar strategies for counteracting OS/NS in POAG were considered. RESULTS A wide variety of studies have proven that antioxidants, among them vitamins B3, C and E, Coenzyme Q10 or melatonin, ω-3/ω-6 fatty acids and other natural compounds (such as coffee, green tea, bear bile, gingko biloba, coleus, tropical fruits, etc.,) may help regulating the intraocular pressure as well as protecting the retinal neurons against OS/NS in POAG. CONCLUSION Based on the impact of antioxidants and ω-3/ω-6 fatty acids at the molecular level in the glaucomatous anterior and posterior eye segments, further studies are needed by integrating all issues involved in glaucoma pathogenesis, endogenous and exogenous risk factors and their interactions that will allow us to reach newer effective biotherapies for preventing glaucomatous irreversible blindness.
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Affiliation(s)
- Maria D. Pinazo-Durán
- Address correspondence to this author at the Ophthalmic Research Unit “Santiago Grisolía”/FISABIO, University Hospital Dr. Peset. Ave/ Gaspar Aguilar 90; 46017, Valencia, Spain; Tel: + 34 961622497;, Fax: + 34 961622748; E-mail:
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Andrés-Guerrero V, Bravo-Osuna I, Pastoriza P, Molina-Martinez IT, Herrero-Vanrell R. Novel technologies for the delivery of ocular therapeutics in glaucoma. J Drug Deliv Sci Technol 2017. [DOI: 10.1016/j.jddst.2017.07.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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17
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Choi SI, Lee E, Akuzum B, Jeong JB, Maeng YS, Kim TI, Kim EK. Melatonin reduces endoplasmic reticulum stress and corneal dystrophy-associated TGFBIp through activation of endoplasmic reticulum-associated protein degradation. J Pineal Res 2017; 63. [PMID: 28580641 DOI: 10.1111/jpi.12426] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Accepted: 05/31/2017] [Indexed: 02/06/2023]
Abstract
Endoplasmic reticulum (ER) stress is emerging as a factor for the pathogenesis of granular corneal dystrophy type 2 (GCD2). This study was designed to investigate the molecular mechanisms underlying the protective effects of melatonin on ER stress in GCD2. Our results showed that GCD2 corneal fibroblasts were more susceptible to ER stress-induced death than were wild-type cells. Melatonin significantly inhibited GCD2 corneal cell death, caspase-3 activation, and poly (ADP-ribose) polymerase 1 cleavage caused by the ER stress inducer, tunicamycin. Under ER stress, melatonin significantly suppressed the induction of immunoglobulin heavy-chain-binding protein (BiP) and activation of inositol-requiring enzyme 1α (IRE1α), and their downstream target, alternative splicing of X-box binding protein 1(XBP1). Notably, the reduction in BiP and IRE1α by melatonin was suppressed by the ubiquitin-proteasome inhibitor, MG132, but not by the autophagy inhibitor, bafilomycin A1, indicating involvement of the ER-associated protein degradation (ERAD) system. Melatonin treatment reduced the levels of transforming growth factor-β-induced protein (TGFBIp) significantly, and this reduction was suppressed by MG132. We also found reduced mRNA expression of the ERAD system components HRD1 and SEL1L, and a reduced level of SEL1L protein in GCD2 cells. Interestingly, melatonin treatments enhanced SEL1L levels and suppressed the inhibition of SEL1L N-glycosylation caused by tunicamycin. In conclusion, this study provides new insights into the mechanisms by which melatonin confers its protective actions during ER stress. The results also indicate that melatonin might have potential as a therapeutic agent for ER stress-related diseases including GCD2.
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Affiliation(s)
- Seung-Il Choi
- Department of Ophthalmology, Corneal Dystrophy Research Institute, Yonsei University College of Medicine, Seoul, Korea
| | - Eunhee Lee
- Department of Ophthalmology, Corneal Dystrophy Research Institute, Yonsei University College of Medicine, Seoul, Korea
| | - Begum Akuzum
- Department of Ophthalmology, Corneal Dystrophy Research Institute, Yonsei University College of Medicine, Seoul, Korea
| | - Jang Bin Jeong
- Department of Ophthalmology, Corneal Dystrophy Research Institute, Yonsei University College of Medicine, Seoul, Korea
| | - Yong-Sun Maeng
- Department of Ophthalmology, Corneal Dystrophy Research Institute, Yonsei University College of Medicine, Seoul, Korea
| | - Tae-Im Kim
- Department of Ophthalmology, Corneal Dystrophy Research Institute, Yonsei University College of Medicine, Seoul, Korea
- Institute of Vision Research, Severance Biomedical Science Institute, Yonsei University College of Medicine, Seoul, Korea
| | - Eung Kweon Kim
- Department of Ophthalmology, Corneal Dystrophy Research Institute, Yonsei University College of Medicine, Seoul, Korea
- Institute of Vision Research, Severance Biomedical Science Institute, Yonsei University College of Medicine, Seoul, Korea
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18
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Melatonin synthesis in the human ciliary body triggered by TRPV4 activation: Involvement of AANAT phosphorylation. Exp Eye Res 2017; 162:1-8. [PMID: 28655604 DOI: 10.1016/j.exer.2017.06.018] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Revised: 06/23/2017] [Accepted: 06/23/2017] [Indexed: 11/22/2022]
Abstract
Melatonin is a substance synthesized in the pineal gland as well as in other organs. This substance is involved in many ocular functions, giving its synthesis in numerous eye structures. Melatonin is synthesized from serotonin through two enzymes, the first limiting step into the synthesis of melatonin being aralkylamine N-acetyltransferase (AANAT). In this current study, AANAT phosphorylation after the activation of TRPV4 was studied using human non-pigmented epithelial ciliary body cells. Firstly, it was necessary to determine the adequate time and dose of the TRPV4 agonist GSK1016790A to reach the maximal phosphorylation of AANAT. An increase of 72% was observed after 5 min incubation with 10 nM GSK (**p < 0.05, n = 6) with a concomitant rise in N-acetyl serotonin and melatonin synthesis. The involvement of a TRPV4 channel in melatonin synthesis was verified by antagonist and siRNA studies as a previous step to studying intracellular signalling. Studies performed on the second messengers involved in GSK induced AANAT phosphorylation were carried out by inhibiting several pathways. In conclusion, the activation of calmodulin and calmodulin-dependent protein kinase II was confirmed, as shown by the cascade seen in AANAT phosphorylation (***p < 0.001, n = 4). This mechanism was also established by measuring N-acetyl serotonin and melatonin levels. In conclusion, the activation of a TRPV4 present in human ciliary body epithelial cells produced an increase in AANAT phosphorylation and a further melatonin increase by a mechanism in which Ca-calmodulin and the calmodulin-dependent protein kinase II are involved.
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19
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Argikar UA, Dumouchel JL, Dunne CE, Bushee AJ. Ocular non-P450 oxidative, reductive, hydrolytic, and conjugative drug metabolizing enzymes. Drug Metab Rev 2017; 49:372-394. [PMID: 28438049 DOI: 10.1080/03602532.2017.1322609] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Metabolism in the eye for any species, laboratory animals or human, is gaining rapid interest as pharmaceutical scientists aim to treat a wide range of so-called incurable ocular diseases. Over a period of decades, reports of metabolic activity toward various drugs and biochemical markers have emerged in select ocular tissues of animals and humans. Ocular cytochrome P450 (P450) enzymes and transporters have been recently reviewed. However, there is a dearth of collated information on non-P450 drug metabolizing enzymes in eyes of various preclinical species and humans in health and disease. In an effort to complement ocular P450s and transporters, which have been well reviewed in the literature, this review is aimed at presenting collective information on non-P450 oxidative, hydrolytic, and conjugative ocular drug metabolizing enzymes. Herein, we also present a list of xenobiotics or drugs that have been reported to be metabolized in the eye.
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Affiliation(s)
- Upendra A Argikar
- a Analytical Sciences and Imaging , Novartis Institutes for Biomedical Research, Inc , Cambridge , MA , USA
| | - Jennifer L Dumouchel
- a Analytical Sciences and Imaging , Novartis Institutes for Biomedical Research, Inc , Cambridge , MA , USA
| | - Christine E Dunne
- b Department of Chemistry , Colorado State University , Fort Collins , CO , USA
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20
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Meng X, Li Y, Li S, Zhou Y, Gan RY, Xu DP, Li HB. Dietary Sources and Bioactivities of Melatonin. Nutrients 2017; 9:E367. [PMID: 28387721 PMCID: PMC5409706 DOI: 10.3390/nu9040367] [Citation(s) in RCA: 187] [Impact Index Per Article: 26.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2017] [Revised: 03/14/2017] [Accepted: 03/31/2017] [Indexed: 12/14/2022] Open
Abstract
Insomnia is a serious worldwide health threat, affecting nearly one third of the general population. Melatonin has been reported to improve sleep efficiency and it was found that eating melatonin-rich foods could assist sleep. During the last decades, melatonin has been widely identified and qualified in various foods from fungi to animals and plants. Eggs and fish are higher melatonin-containing food groups in animal foods, whereas in plant foods, nuts are with the highest content of melatonin. Some kinds of mushrooms, cereals and germinated legumes or seeds are also good dietary sources of melatonin. It has been proved that the melatonin concentration in human serum could significantly increase after the consumption of melatonin containing food. Furthermore, studies show that melatonin exhibits many bioactivities, such as antioxidant activity, anti-inflammatory characteristics, boosting immunity, anticancer activity, cardiovascular protection, anti-diabetic, anti-obese, neuroprotective and anti-aging activity. This review summaries the dietary sources and bioactivities of melatonin, with special attention paid to the mechanisms of action.
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Affiliation(s)
- Xiao Meng
- Guangdong Provincial Key Laboratory of Food, Nutrition and Health, Department of Nutrition, School of Public Health, Sun Yat-sen University, Guangzhou 510080, China.
| | - Ya Li
- Guangdong Provincial Key Laboratory of Food, Nutrition and Health, Department of Nutrition, School of Public Health, Sun Yat-sen University, Guangzhou 510080, China.
| | - Sha Li
- School of Chinese Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong 999077, China.
| | - Yue Zhou
- Guangdong Provincial Key Laboratory of Food, Nutrition and Health, Department of Nutrition, School of Public Health, Sun Yat-sen University, Guangzhou 510080, China.
| | - Ren-You Gan
- School of Biological Sciences, The University of Hong Kong, Hong Kong 999077, China.
| | - Dong-Ping Xu
- Guangdong Provincial Key Laboratory of Food, Nutrition and Health, Department of Nutrition, School of Public Health, Sun Yat-sen University, Guangzhou 510080, China.
| | - Hua-Bin Li
- Guangdong Provincial Key Laboratory of Food, Nutrition and Health, Department of Nutrition, School of Public Health, Sun Yat-sen University, Guangzhou 510080, China.
- South China Sea Bioresource Exploitation and Utilization Collaborative Innovation Center, Sun Yat-sen University, Guangzhou 510006, China.
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Sánchez-López E, Espina M, Doktorovova S, Souto EB, García ML. Lipid nanoparticles (SLN, NLC): Overcoming the anatomical and physiological barriers of the eye - Part II - Ocular drug-loaded lipid nanoparticles. Eur J Pharm Biopharm 2016; 110:58-69. [PMID: 27789359 DOI: 10.1016/j.ejpb.2016.10.013] [Citation(s) in RCA: 108] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
In the recent decades, various controlled delivery systems have been introduced with the aim to improve solubility, stability and bioavailability of poorly absorbed drugs. Among all, lipid nanoparticles gather interesting properties as drug or gene delivery carriers. These systems, composed either of solid lipids (SLN) or of solid and liquid lipids (NLC) stabilized with surfactants, combine the advantages of other colloidal particles such as polymeric nanoparticles, fat emulsions and liposomes avoiding their main disadvantages. Lipid nanoparticles represent an interesting approach for eye drug delivery as they can improve the corneal absorption of drugs enhancing their bioavailability. The Generally Recognized as Safe status of formulation excipients, the scaling-up facilities and the possibility of sterilization, make them suitable for industrial production. In this review, the latest findings, potential applications, and challenges related to the use of lipid nanoparticles for ocular drug delivery are comprehensively discussed.
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Affiliation(s)
- E Sánchez-López
- Department of Pharmacy, Pharmaceutical Technology and Physical Chemistry, Faculty of Pharmacy, University of Barcelona, Av. Joan XXIII s/n, 08028 Barcelona, Spain; Institute of Nanoscience and Nanotechnology, University of Barcelona, Av. Joan XXIII s/n, 08028 Barcelona, Spain
| | - M Espina
- Department of Pharmacy, Pharmaceutical Technology and Physical Chemistry, Faculty of Pharmacy, University of Barcelona, Av. Joan XXIII s/n, 08028 Barcelona, Spain; Institute of Nanoscience and Nanotechnology, University of Barcelona, Av. Joan XXIII s/n, 08028 Barcelona, Spain
| | - S Doktorovova
- Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Coimbra (FFUC), Polo das Ciências da Saúde, Azinhaga de Santa Comba, 3000-548 Coimbra, Portugal
| | - E B Souto
- Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Coimbra (FFUC), Polo das Ciências da Saúde, Azinhaga de Santa Comba, 3000-548 Coimbra, Portugal; REQUIMTE/LAQV, Group of Pharmaceutical Technology, Faculty of Pharmacy, University of Coimbra, Coimbra, Portugal
| | - M L García
- Department of Pharmacy, Pharmaceutical Technology and Physical Chemistry, Faculty of Pharmacy, University of Barcelona, Av. Joan XXIII s/n, 08028 Barcelona, Spain; Institute of Nanoscience and Nanotechnology, University of Barcelona, Av. Joan XXIII s/n, 08028 Barcelona, Spain.
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Polyphenol Stilbenes: Molecular Mechanisms of Defence against Oxidative Stress and Aging-Related Diseases. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2015; 2015:340520. [PMID: 26180583 PMCID: PMC4477219 DOI: 10.1155/2015/340520] [Citation(s) in RCA: 134] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/11/2014] [Accepted: 01/21/2015] [Indexed: 12/13/2022]
Abstract
Numerous studies have highlighted the key roles of oxidative stress and inflammation in aging-related diseases such as obesity, type 2 diabetes, age-related macular degeneration (AMD), and Alzheimer's disease (AD). In aging cells, the natural antioxidant capacity decreases and the overall efficiency of reparative systems against cell damage becomes impaired. There is convincing data that stilbene compounds, a diverse group of natural defence phenolics, abundant in grapes, berries, and conifer bark waste, may confer a protective effect against aging-related diseases. This review highlights recent data helping to clarify the molecular mechanisms involved in the stilbene-mediated protection against oxidative stress. The impact of stilbenes on the nuclear factor-erythroid-2-related factor-2 (Nrf2) mediated cellular defence against oxidative stress as well as the potential roles of SQSTM1/p62 protein in Nrf2/Keap1 signaling and autophagy will be summarized. The therapeutic potential of stilbene compounds against the most common aging-related diseases is discussed.
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Pescosolido N, Gatto V, Stefanucci A, Rusciano D. Oral treatment with the melatonin agonist agomelatine lowers the intraocular pressure of glaucoma patients. Ophthalmic Physiol Opt 2015; 35:201-5. [DOI: 10.1111/opo.12189] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2014] [Accepted: 11/29/2014] [Indexed: 01/21/2023]
Affiliation(s)
- Nicola Pescosolido
- Facoltà di Medicina e Odontoiatria; Università di Roma La Sapienza; Rome Italy
| | - Vittorio Gatto
- Facoltà di Medicina e Odontoiatria; Università di Roma La Sapienza; Rome Italy
| | - Alessio Stefanucci
- Facoltà di Medicina e Odontoiatria; Università di Roma La Sapienza; Rome Italy
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Leonardi A, Bucolo C, Drago F, Salomone S, Pignatello R. Cationic solid lipid nanoparticles enhance ocular hypotensive effect of melatonin in rabbit. Int J Pharm 2014; 478:180-186. [PMID: 25448580 DOI: 10.1016/j.ijpharm.2014.11.032] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2014] [Revised: 11/11/2014] [Accepted: 11/13/2014] [Indexed: 01/29/2023]
Abstract
The study was aimed at evaluating whether the ocular hypotensive effect of melatonin (MEL) was enhanced by its encapsulation in cationic solid lipid nanoparticles (cSLN), as well as at determining the tolerability of these formulations on the ocular surface. MEL was loaded in cSLN that had already been shown to be suitable for ophthalmic use. The formulations were prepared using Softisan(®) 100 as the main lipid matrix, with the presence of either stearic (SA) or palmitic acid (PA) as lipid modifiers. A fixed positive charge was provided by the addition of a cationic lipid (didecyldimethylammonium bromide). The ocular hypotensive effect was evaluated by measuring the intraocular pressure (IOP) during 24h in albino rabbits. MEL elicited a significant (p<0.01) IOP reduction in rabbit eye. All the formulations tested in vivo demonstrated a good tolerability. The nanocarrier containing SA was the most effective in terms of IOP reduction (maximum IOP reduction: -7 mmHg), and its effect lasted approximately 24h. The experimental data indicate that the new formulations based on cSLN loaded with MEL represent a potent anti-glaucoma treatment with a safe profile, warranting further clinical evaluation of the proposed nanotechnological strategy.
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Affiliation(s)
- Antonio Leonardi
- NANO-i, Research Center of Ocular Nanotechnology, Department of Drug Sciences, University of Catania, Catania, Italy
| | - Claudio Bucolo
- Department of Clinical and Molecular Biomedicine, Section of Pharmacology and Biochemistry, School of Medicine, University of Catania, Viale A. Doria 6, Catania 95125, Italy.
| | - Filippo Drago
- Department of Clinical and Molecular Biomedicine, Section of Pharmacology and Biochemistry, School of Medicine, University of Catania, Viale A. Doria 6, Catania 95125, Italy
| | - Salvatore Salomone
- Department of Clinical and Molecular Biomedicine, Section of Pharmacology and Biochemistry, School of Medicine, University of Catania, Viale A. Doria 6, Catania 95125, Italy
| | - Rosario Pignatello
- NANO-i, Research Center of Ocular Nanotechnology, Department of Drug Sciences, University of Catania, Catania, Italy
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Hybrid formulations of liposomes and bioadhesive polymers improve the hypotensive effect of the melatonin analogue 5-MCA-NAT in rabbit eyes. PLoS One 2014; 9:e110344. [PMID: 25329636 PMCID: PMC4203784 DOI: 10.1371/journal.pone.0110344] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2014] [Accepted: 09/18/2014] [Indexed: 01/01/2023] Open
Abstract
For the treatment of chronic ocular diseases such as glaucoma, continuous instillations of eye drops are needed. However, frequent administrations of hypotensive topical formulations can produce adverse ocular surface effects due to the active substance or other components of the formulation, such as preservatives or other excipients. Thus the development of unpreserved formulations that are well tolerated after frequent instillations is an important challenge to improve ophthalmic chronic topical therapies. Furthermore, several components can improve the properties of the formulation in terms of efficacy. In order to achieve the mentioned objectives, we have developed formulations of liposomes (150–200 nm) containing components similar to those in the tear film and loaded with the hypotensive melatonin analog 5-methoxycarbonylamino-N-acetyltryptamine (5-MCA-NAT, 100 µM). These formulations were combined with mucoadhesive (sodium hyaluronate or carboxymethylcellulose) or amphiphilic block thermosensitive (poloxamer) polymers to prolong the hypotensive efficacy of the drug. In rabbit eyes, the decrease of intraocular pressure with 5-MCA-NAT-loaded liposomes that were dispersed with 0.2% sodium hyaluronate, 39.1±2.2%, was remarkably higher compared to other liposomes formulated without or with other bioadhesive polymers, and the effect lasted more than 8 hours. According to the results obtained in the present work, these technological strategies could provide an improved modality for delivering therapeutic agents in patients with glaucoma.
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Singh M, Jadhav HR. Melatonin: functions and ligands. Drug Discov Today 2014; 19:1410-8. [PMID: 24792719 DOI: 10.1016/j.drudis.2014.04.014] [Citation(s) in RCA: 125] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2013] [Revised: 03/16/2014] [Accepted: 04/22/2014] [Indexed: 12/15/2022]
Abstract
Melatonin is a chronobiotic substance that acts as synchronizer by stabilizing bodily rhythms. Its synthesis occurs in various locations throughout the body, including the pineal gland, skin, lymphocytes and gastrointestinal tract (GIT). Its synthesis and secretion is controlled by light and dark conditions, whereby light decreases and darkness increases its production. Thus, melatonin is also known as the 'hormone of darkness'. Melatonin and analogs that bind to the melatonin receptors are important because of their role in the management of depression, insomnia, epilepsy, Alzheimer's disease (AD), diabetes, obesity, alopecia, migraine, cancer, and immune and cardiac disorders. In this review, we discuss the mechanism of action of melatonin in these disorders, which could aid in the design of novel melatonin receptor ligands.
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Affiliation(s)
- Mahaveer Singh
- Department of Pharmacy, Birla Institute of Technology and Sciences Pilani, Pilani Campus, Vidya Vihar, Pilani 333031, Rajasthan, India.
| | - Hemant R Jadhav
- Department of Pharmacy, Birla Institute of Technology and Sciences Pilani, Pilani Campus, Vidya Vihar, Pilani 333031, Rajasthan, India
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Chua B, Goldberg I. Neuroprotective agents in glaucoma therapy: recent developments and future directions. EXPERT REVIEW OF OPHTHALMOLOGY 2014. [DOI: 10.1586/eop.10.55] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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Sainath S, Swetha CH, Reddy PS. What Do We (Need to) Know About the Melatonin in Crustaceans? ACTA ACUST UNITED AC 2013; 319:365-77. [DOI: 10.1002/jez.1800] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2012] [Revised: 03/25/2013] [Accepted: 04/01/2013] [Indexed: 11/06/2022]
Affiliation(s)
- S.B. Sainath
- Department of Biotechnology; Sri Venkateswara University; Tirupati, Andhra Pradesh; India
| | - CH. Swetha
- Department of Biotechnology; Sri Venkateswara University; Tirupati, Andhra Pradesh; India
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Tosini G, Baba K, Hwang CK, Iuvone PM. Melatonin: an underappreciated player in retinal physiology and pathophysiology. Exp Eye Res 2012; 103:82-9. [PMID: 22960156 DOI: 10.1016/j.exer.2012.08.009] [Citation(s) in RCA: 103] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2012] [Revised: 08/21/2012] [Accepted: 08/23/2012] [Indexed: 12/14/2022]
Abstract
In the vertebrate retina, melatonin is synthesized by the photoreceptors with high levels of melatonin at night and lower levels during the day. Melatonin exerts its influence by interacting with a family of G-protein-coupled receptors that are negatively coupled with adenylyl cyclase. Melatonin receptors belonging to the subtypes MT(1) and MT(2) have been identified in the mammalian retina. MT(1) and MT(2) receptors are found in all layers of the neural retina and in the retinal pigmented epithelium. Melatonin in the eye is believed to be involved in the modulation of many important retinal functions; it can modulate the electroretinogram (ERG), and administration of exogenous melatonin increases light-induced photoreceptor degeneration. Melatonin may also have protective effects on retinal pigment epithelial cells, photoreceptors and ganglion cells. A series of studies have implicated melatonin in the pathogenesis of age-related macular degeneration, and melatonin administration may represent a useful approach to prevent and treat glaucoma. Melatonin is used by millions of people around the world to retard aging, improve sleep performance, mitigate jet lag symptoms, and treat depression. Administration of exogenous melatonin at night may also be beneficial for ocular health, but additional investigation is needed to establish its potential.
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Affiliation(s)
- Gianluca Tosini
- Circadian Rhythms and Sleep Disorders Program, Neuroscience Institute, Morehouse School of Medicine, Atlanta, GA 30310, USA.
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Crooke A, Huete-Toral F, Martínez-Águila A, Colligris B, Pintor J. Ocular disorders and the utility of animal models in the discovery of melatoninergic drugs with therapeutic potential. Expert Opin Drug Discov 2012; 7:989-1001. [PMID: 22860991 DOI: 10.1517/17460441.2012.714769] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
INTRODUCTION The pineal indole-derived hormone melatonin is a modulator of circadian and seasonal rhythms with an important role in ocular health and disease. This could be due to specific melatonin receptors that have been identified in structures such as cornea, lens, ciliary body, retina, choroid and sclera. In addition, a local synthesis of melatonin occurs in several of these ocular tissues. AREAS COVERED The authors review existing literature on the most common animal models where ocular melatonin actions have been tested. The therapeutic potential of melatonin in diabetic keratopathy and retinopathy, keratitis, cataracts, glaucoma, uveitis, age-related macular degeneration and retinitis pigmentosa is discussed. Furthermore, the authors comment on the usefulness of different animal models for the development of melatoninergic drugs with therapeutic potential. EXPERT OPINION The use of animals for the study of ocular diseases and the potentiality of melatonin and its analogs, as future therapeutic drugs, should be performed on the basis of a rationale study. It is important to note that melatonin receptors seem to be widespread all over the eye. This strongly suggests that, in order to modify the physiology and biochemistry of malfunctioning ocular tissue, the melatonin receptors which are present in that tissue must be first identified. Second there is the need to confirm that those receptors targeted perform the desirable responses, and as a third measure, to use selective agonists (or antagonists) instead of melatonin. However, although some animals mimic ocular pathologies relatively well, and these can be used in melatonin studies, there is still a long way to go till some of the results obtained in animal models could be used for human therapy.
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Affiliation(s)
- Almudena Crooke
- Departamento de Bioquímica y Biología Molecular IV, E.U. Óptica, Universidad Complutense de Madrid, C/Arcos de Jalón 118, Madrid, Spain
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Alqawlaq S, Huzil JT, Ivanova MV, Foldvari M. Challenges in neuroprotective nanomedicine development: progress towards noninvasive gene therapy of glaucoma. Nanomedicine (Lond) 2012; 7:1067-83. [PMID: 22846092 DOI: 10.2217/nnm.12.69] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Over the past decade the application of gene therapy of retinal diseases such as glaucoma has produced promising results. However, optic nerve regeneration and restoration of vision in patients with glaucoma is still far from reality. Neuroprotective approaches in the form of gene therapy may provide significant advantages, but are still limited by many factors both at the organ and cellular levels. In general, gene delivery systems for eye diseases range from simple eye drops and ointments to more advanced bio- and nanotechnology-based systems such as muco-adhesive systems, polymers, liposomes and ocular inserts. Most of these technologies were developed for front-of-the-eye ophthalmic therapies and are not applicable as back-of-the-eye delivery systems. Currently, only the invasive intravitreal injections are capable of successfully delivering genes to the retina. Here we review the challenges and possible strategies for the noninvasive gene therapy of glaucoma including the barriers in the eye and in neural cells, and present a cross-sectional view of gene delivery as it pertains to the prevention and treatment of glaucoma.
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Affiliation(s)
- Samih Alqawlaq
- School of Pharmacy, University of Waterloo, 200 University Avenue West, Waterloo, ON, N2L 3G1, Canada
| | - J Torin Huzil
- School of Pharmacy, University of Waterloo, 200 University Avenue West, Waterloo, ON, N2L 3G1, Canada
| | - Marina V Ivanova
- School of Pharmacy, University of Waterloo, 200 University Avenue West, Waterloo, ON, N2L 3G1, Canada
| | - Marianna Foldvari
- School of Pharmacy, University of Waterloo, 200 University Avenue West, Waterloo, ON, N2L 3G1, Canada
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Thaler S, Fiedorowicz M, Grieb P, Wypych Z, Knap N, Borowik T, Zawada K, Kaminski J, Wozniak M, Rejdak R, Zrenner E, Schuettauf F. Neuroprotective effects of tempol acyl esters against retinal ganglion cell death in a rat partial optic nerve crush model. Acta Ophthalmol 2011; 89:e555-60. [PMID: 21645284 DOI: 10.1111/j.1755-3768.2011.02180.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
PURPOSE The aim of this study is to search for more effective derivatives of the superoxide dismutase mimetic tempol (4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl). Although tempol is neuroprotective in a rat partial optic nerve crush (PONC) model, relatively high doses are required to exert this effect. METHODS Tempol acyl esters with different-length fatty acids (tempol-C4, tempol-C8, tempol-C12 and tempol-C16) were synthesized and the following properties were evaluated: water-octanol partition coefficient, liposome-liposome energy transfer, and electron paramagnetic resonance (EPR). Brown Norway rats underwent PONC and received tempol or acyl esters intraperitoneally once daily for 7 consecutive days. We then compared the effects of tempol and its four esters on retinal ganglion cell (RGC) damage using a retrograde labelling method. RESULTS The water-octanol partition coefficient increased with increasing length of attached acyl chain. However, the energy of the liposome-liposome transfer seemed to be optimal for tempol-C8 and tempol-C12. The EPR signal was very similar for all tested compounds, suggesting similar efficiency of superoxide scavenging. Partial optic nerve crush in vehicle-treated animals reduced RGC numbers by approx. 59% when compared with sham-operated eyes. Tempol did not affect RGC loss at a dose of 1 mg/kg. In contrast, at molar doses equivalent to 1 mg/kg of tempol, tempol-C8 showed a significant neuroprotective effect, whereas tempol-C4, tempol-C12 and tempol-C16 did not act neuroprotectively. CONCLUSION Manipulating the hydrophobicity of tempol seems to be a promising tool for developing more potent neuroprotectants in the PONC degeneration model. However, the resulting compounds need further pharmacological evaluation.
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Affiliation(s)
- Sebastian Thaler
- Centre for Ophthalmology, University of Tuebingen, Tuebingen, Germany.
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Ghanem AA, Mady SM, Arafa LF, Elewa AM. Serotonin and hydroxyindolacetic acid levels in aqueous humor of patients with primary open-angle glaucoma. Interv Med Appl Sci 2011. [DOI: 10.1556/imas.3.2011.2.3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Abstract
Purpose
To investigate the levels of 5-HT (serotonin, 5-hydroxytryptamine) and 5-HIAA (5-hydroxyindolacetic acid) in the aqueous humor and plasma of subjects with primary open-angle glaucoma (POAG) and to correlate their concentrations with the severity of glaucoma.
Methods
Thirty-five patients with POAG and 30 patients with senile cataract (control group) of matched age and gender were included in the study prospectively. Aqueous humor samples were obtained by paracentesis from glaucoma and cataract patients who were undergoing elective surgery. Aqueous humor and corresponding plasma samples were analyzed for 5-HT and 5-HIAA levels by high performance liquid chromatography with electrochemical detection.
Results
5-HT and 5-HIAA levels were significantly higher in the aqueous humor of POAG patients than in that of the comparative group of cataract patients. There was no significant difference in the 5-HT and 5-HIAA levels in plasma of POAG and cataract patients. A positive correlation was found between 5-HT and 5-HIAA in the aqueous humor of POAG patients. The 5-HT turnover (5-HIAA/5-HT) was higher in POAG than in cataract patients, but the difference was not significant. No significant correlation was found between levels and severity of visual field loss.
Conclusion
Increased levels of 5-HT and 5-HIAA aqueous humor may be associated with POAG.
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Affiliation(s)
- Asaad A. Ghanem
- 1 Ophthalmology Center, Faculty of Medicine, Mansoura University, Mansoura, Egypt
| | - Salah M. Mady
- 2 Ophthalmology Department, Faculty of Medicine, Benha University, Benha, Egypt
| | - Lamiaa F. Arafa
- 3 Department of Medical Biochemistry, Faculty of Medicine, Mansoura University, Mansoura, Egypt
| | - Ahmed M. Elewa
- 4 Department of Clinical Pathology, Faculty of Medicine, Mansoura University, Mansoura, Egypt
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Lax P, Otalora BB, Esquiva G, Rol MDLÁ, Madrid JA, Cuenca N. Circadian dysfunction in P23H rhodopsin transgenic rats: effects of exogenous melatonin. J Pineal Res 2011; 50:183-91. [PMID: 21062354 DOI: 10.1111/j.1600-079x.2010.00827.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
This study focuses on the effects of retinal degeneration on the circadian patterns of P23H rats, as well as on the effect of exogenous melatonin administration. To this end, the body temperature of P23H and Sprague-Dawley rats was continuously monitored and their retinas examined at different stages of degeneration, by means of histological labeling and electroretinogram recordings. Melatonin (2 mg/kg BW/day) was supplied ad libitum throughout the experiment to a subset of animals. The body temperature recordings from wild-type and mutant animals showed no differences in the periodogram and the pattern of the mean waveform. However, a progressive decrease in the relative amplitude of the rhythm (RA), a decline in the coupling strength of the rhythm to environmental zeitgebers (interdaily stability, IS) and increased rhythm fragmentation (intradaily variability, IV) were observed in P23H rats, when compared to wild-type animals. The P23H animals showed a progressive decrease in light-induced retinal responses until reaching 18 months of age. By this age, all photoreceptors had already disappeared, and no responses were found in the EGRs. Exogenous administration of melatonin improved the visual response of P23H rats. In fact, the maximum b-wave recorded at 14 months of age was significantly higher in melatonin-treated P23H rats than in the control animals. Furthermore, the maximum b-wave recorded for P23H rats at the age of 14 months significantly correlated with RA, IS, and IV. This leads us to conclude that vision loss in P23H rats is correlated with a progressive fragmentation of their circadian patterns. Both effects are partially reversed by melatonin administration.
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Affiliation(s)
- Pedro Lax
- Department of Physiology, Genetics and Microbiology, University of Alicante, San Vicente del Raspeig, Spain.
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Agorastos A, Huber CG. The role of melatonin in glaucoma: implications concerning pathophysiological relevance and therapeutic potential. J Pineal Res 2011; 50:1-7. [PMID: 21073517 DOI: 10.1111/j.1600-079x.2010.00816.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Glaucoma is a frequent ophthalmologic condition leading to chronic progressive optic neuropathy, which can result in visual impairment and blindness. In addition, glaucoma is associated with a dysregulation of circadian rhythms, as well as with a high incidence of sleep disorders, depression, and anxiety. However, because of their high comorbidity in older age, these conditions have not received much scientific attention and are often undertreated. In the current paper, we review the available literature on the role of melatonergic mechanisms in glaucoma, regulation of circadian rhythms, and depression. The literature is presented as a narrative review, providing an overview on the most important and clinically relevant publications. Recently, there has been evidence for a progressive loss of intrinsically photosensitive retinal ganglion cells (ipRGC) because of oxidative stress in glaucoma. As ipRGC are responsible for the photic transduction to the circadian system and subsequent melatonin secretion, and melatonin is involved in the pathophysiology of circadian desynchronization, sleep disorder, and depression, an impairment of photo-dependent melatonergic signaling may be a common pathway connecting glaucoma with these comorbidities. This fact, as well as the proven retinal neuroprotective role of melatonin, suggests that melatonergic drugs provide a potentially promising treatment strategy supplementing the management of intraocular pressure by pharmacological and surgical measures. Additionally, multidisciplinary treatment focusing on depression and normalization of circadian rhythms might be beneficial for glaucoma patients. Furthermore, glaucoma might be a useful model for studying the pathophysiological interactions between the melatonergic, circadian, and mood systems.
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Affiliation(s)
- Agorastos Agorastos
- Department of Psychiatry and Psychotherapy, Centre for Psychosocial Medicine, University Medical Centre Hamburg-Eppendorf, Hamburg, Germany.
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Rastmanesh R. Potential of melatonin to treat or prevent age-related macular degeneration through stimulation of telomerase activity. Med Hypotheses 2011; 76:79-85. [DOI: 10.1016/j.mehy.2010.08.036] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2010] [Accepted: 08/07/2010] [Indexed: 12/15/2022]
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Rosenstein RE, Pandi-Perumal SR, Srinivasan V, Spence DW, Brown GM, Cardinali DP. Melatonin as a therapeutic tool in ophthalmology: implications for glaucoma and uveitis. J Pineal Res 2010; 49:1-13. [PMID: 20492443 DOI: 10.1111/j.1600-079x.2010.00764.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Several lines of evidence support the view that increased free radical generation and altered nitric oxide (NO) metabolism play a role in the pathogenesis of highly prevalent ocular diseases, such as glaucoma and uveitis. Data are discussed indicating that melatonin, being an efficient antioxidant that displays antinitridergic properties, has a promising role in the treatment of these ocular dysfunctions. Melatonin synthesis occurs in the eye of most species, and melatonin receptors are localized in different ocular structures. In view of the fact that melatonin lacks significant adverse collateral effects even at high doses, the application of melatonin could potentially protect ocular tissues by effectively scavenging free radicals and excessive amounts of NO generated in the glaucomatous or uveitic eye.
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Affiliation(s)
- Ruth E Rosenstein
- Department of Human Biochemistry, School of Medicine, CEFyBO, University of Buenos Aires, CONICET, Buenos Aires, Argentina.
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Chakrabarti S, Ghanekar Y, Kaur K, Kaur I, Mandal AK, Rao KN, Parikh RS, Thomas R, Majumder PP. A polymorphism in the CYP1B1 promoter is functionally associated with primary congenital glaucoma. Hum Mol Genet 2010; 19:4083-90. [DOI: 10.1093/hmg/ddq309] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Sampaio LDFS. An unexpected effect of 5-MCA-NAT in chick retinal development. Int J Dev Neurosci 2009; 27:511-5. [PMID: 19596433 DOI: 10.1016/j.ijdevneu.2009.07.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2009] [Revised: 06/22/2009] [Accepted: 07/01/2009] [Indexed: 10/20/2022] Open
Abstract
Luzindole is an unselective antagonist of the melatonin receptors and melatonin's other binding sites, although some exceptions have been observed in chick retinal neurodevelopment, where this unselective antagonist does not block melatonin's inhibitory effect on the adenylate cyclase enzyme, probably due to the presence of some other melatonin receptor(s) or binding site(s). The present study investigated the modulation of cyclic adenosine 3'-5'-monophosphate (cAMP) levels via MT3 melatonin-binding sites, located within the QR2 (dihydronicotinamide riboside: quinone oxidoreductase 2) enzyme, by observing the response to luzindole. Embryonic and post-hatch retinas, incubated with a selective agonist for the MT3 melatonin-binding site 5-methoxycarbonylamino-N-acetyltryptamine (5-MCA-NAT, 10 or 100 nM), had an increase in cAMP accumulation relative to control retinas. Luzindole (5microM) inhibited the 5-MCA-NAT stimulatory effect at all ages tested. The agonist 5-MCA-NAT enhanced the melatonin inhibitory effect on cAMP levels stimulated by forskolin (5microM), but not the stimulatory forskolin effect. The results suggest that MT3 melatonin-binding sites are present in embryonic and post-hatch chick retinas and that luzindole more selectively blocks the 5-MCA-NAT effect on cAMP accumulation than it blocks the melatonin inhibitory effect via G protein-coupled receptors in chick retinal neurodevelopment.
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Affiliation(s)
- Lucia de Fatima Sobral Sampaio
- Laboratório de Bioquímica do Desenvolvimento do Sistema Nervoso, Instituto de Ciências Biológicas, Universidade Federal do Pará, Rua Augusto Corrêa, 1, CEP: 66075-110 Belém, PA, Brazil.
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Ghai K, Zelinka C, Fischer AJ. Serotonin released from amacrine neurons is scavenged and degraded in bipolar neurons in the retina. J Neurochem 2009; 111:1-14. [PMID: 19619137 DOI: 10.1111/j.1471-4159.2009.06270.x] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The neurotransmitter serotonin is synthesized in the retina by one type of amacrine neuron but accumulates in bipolar neurons in many vertebrates. The mechanisms, functions and purpose underlying serotonin accumulation in bipolar cells remain unknown. Here, we demonstrate that exogenous serotonin transiently accumulates in a distinct type of bipolar neuron. KCl-mediated depolarization causes the depletion of serotonin from amacrine neurons and, subsequently, serotonin is taken-up by bipolar neurons. The accumulation of endogenous and exogenous serotonin by bipolar neurons is blocked by selective reuptake inhibitors. Exogenous serotonin is specifically taken-up by bipolar neurons even when serotonin-synthesizing amacrine neurons are destroyed; excluding the possibility that serotonin diffuses through gap junctions from amacrine into bipolar neurons. Further, inhibition of monoamine oxidase A prevents the degradation of serotonin in bipolar neurons, suggesting that monoamine oxidase A is present in these neurons. However, the vesicular monoamine transporter 2 is present only in amacrine cells suggesting that serotonin is not transported into synaptic vesicles and reused as a transmitter in the bipolar neurons. We conclude that the serotonin-accumulating bipolar neurons perform glial functions in the retina by actively transporting and degrading serotonin that is synthesized in neighboring amacrine cells.
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Affiliation(s)
- Kanika Ghai
- Department of Neuroscience, The Ohio State University, Columbus, Ohio, USA
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Fridlich R, Delalande F, Jaillard C, Lu J, Poidevin L, Cronin T, Perrocheau L, Millet-Puel G, Niepon ML, Poch O, Holmgren A, Van Dorsselaer A, Sahel JA, Léveillard T. The thioredoxin-like protein rod-derived cone viability factor (RdCVFL) interacts with TAU and inhibits its phosphorylation in the retina. Mol Cell Proteomics 2009; 8:1206-18. [PMID: 19279044 DOI: 10.1074/mcp.m800406-mcp200] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Rod-derived cone viability factor (RdCVF) is produced by the Nxnl1 gene that codes for a second polypeptide, RdCVFL, by alternative splicing. Although the role of RdCVF in promoting cone survival has been described, the implication of RdCVFL, a putative thioredoxin enzyme, in the protection of photoreceptors is presently unknown. Using a proteomics approach we identified 90 proteins interacting with RdCVFL including the microtubule-binding protein TAU. We demonstrate that the level of phosphorylation of TAU is increased in the retina of the Nxnl1(-/-) mice as it is hyperphosphorylated in the brain of patients suffering from Alzheimer disease, presumably in some cases through oxidative stress. Using a cell-based assay, we show that RdCVFL inhibits TAU phosphorylation. In vitro, RdCVFL protects TAU from oxidative damage. Photooxidative stress is implicated in retinal degeneration, particularly in retinitis pigmentosa, where it is considered to be a contributor to secondary cone death. The functional interaction between RdCVFL and TAU described here is the first characterization of the RdCVFL signaling pathway involved in neuronal cell death mediated by oxidative stress.
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Affiliation(s)
- Ram Fridlich
- double daggerInstitut de la Vision, INSERM UMR592, 17 rue Moreau, 75012 Paris, France
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44
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Ophthalmic formulations of the intraocular hypotensive melatonin agent 5-MCA-NAT. Exp Eye Res 2009; 88:504-11. [DOI: 10.1016/j.exer.2008.11.004] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2008] [Revised: 09/22/2008] [Accepted: 11/03/2008] [Indexed: 11/19/2022]
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Wiechmann AF, Summers JA. Circadian rhythms in the eye: The physiological significance of melatonin receptors in ocular tissues. Prog Retin Eye Res 2008; 27:137-60. [DOI: 10.1016/j.preteyeres.2007.10.001] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Abstract
Glaucoma is a leading cause of blindness, estimated to affect 60 million people by 2010, and represents a heterogeneous group of neurodegenerative disease. The two major types of glaucoma include primary open-angle glaucoma (POAG) and primary congenital glaucoma (PCG). A genetically heterogeneous group of developmental disorders known as anterior segment dysgenesis (ASD) have been reported to be associated with increased intraocular pressure (IOP) and glaucoma. These include Peters' anomaly, Rieger's anomaly, aniridia, iris hypoplasia, and iridogoniodysgenesis. Genetic linkage analysis and mutation studies have identified CYP1B1 as a causative gene in PCG, as a modifier gene in POAG, and, on rare occasions, as causative gene in POAG as well as in several ASD disorders. CYP1B1-deficient mice exhibit abnormalities in their ocular drainage structure and trabecular meshwork that are similar to those reported in human PCG patients. Accordingly, it is speculated that diminished or absent metabolism of key endogenous CYP1B1 substrates adversely affects the development of the trabecular meshwork. CYP1B1 protein is involved in the metabolism of steroids, retinol and retinal, arachidonate, and melatonin. The conserved expression of CYP1B1 in both murine and human eyes, its higher expression in fetal than adult eyes, and its biochemical properties are consistent with this hypothesis. The exact role of CYP1B1 in the pathogenesis of glaucoma and other ASD disorders remains to be elucidated.
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Affiliation(s)
- Vasilis Vasiliou
- Molecular Toxicology & Environmental Health Sciences Program, Department of Pharmaceutical Sciences, University of Colorado Health Sciences Center, Denver, CO 80262, USA.
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Moreira EF, Kantorow M, Rodriguez IR. Peroxiredoxin 3 (PDRX3) is highly expressed in the primate retina especially in blue cones. Exp Eye Res 2007; 86:452-5. [PMID: 18078932 DOI: 10.1016/j.exer.2007.10.020] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2007] [Accepted: 10/24/2007] [Indexed: 12/11/2022]
Abstract
Oxidative stress and loss of mitochondrial function have been implicated in age-related ocular diseases and thus studying enzymes involved in these processes may be of particular importance in these diseases. Peroxiredoxin III (PRDX3) is one of a family of six known peroxiredoxins which are known to protect cells against oxidative damage. PRDX3 is localized to the mitochondria and has been reported to be induced by hydrogen peroxide in aortic endothelial and lens epithelial cells. Using a highly specific commercially available antibody, PRDX3 was readily detected by immunoblot in monkey neural retina. Immunohistochemical analysis of human and monkey retina localized PRDX3 mainly to the photoreceptor inner segments, the outer and inner plexiform layers, and the ganglion cells. These are areas of known high mitochondrial content. In the monkey retina some of the cone inner segments were much more strongly labeled than others. Dual labeling experiments using specific anti-cone opsin antibodies determined that the high expressing cones were of the blue subtype. By contrast, in the human retina all of the cone inner segments were immunoreactive. This difference may be due to a postmortem induction of PRDX3 in the human sample. These results suggest that PRDX3 may be important in protecting photoreceptor mitochondria especially in blue cones.
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Affiliation(s)
- Ernesto F Moreira
- Mechanisms of Retinal Disease Section, LRCMB, National Eye Institute, NIH, Bethesda, MD 20892, USA
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