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Blasiak J, Chojnacki J, Szczepanska J, Fila M, Chojnacki C, Kaarniranta K, Pawlowska E. Epigallocatechin-3-Gallate, an Active Green Tea Component to Support Anti-VEGFA Therapy in Wet Age-Related Macular Degeneration. Nutrients 2023; 15:3358. [PMID: 37571296 PMCID: PMC10421466 DOI: 10.3390/nu15153358] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Revised: 07/19/2023] [Accepted: 07/27/2023] [Indexed: 08/13/2023] Open
Abstract
Age-related macular degeneration (AMD) is a largely incurable disease and an emerging problem in aging societies. It occurs in two forms, dry and wet (exudative, neovascular), which may cause legal blindness and sight loss. Currently, there is not any effective treatment for dry AMD. Meanwhile, repeated intravitreal injections with antibodies effective against vascular endothelial growth factor A (VEGFA) slow down wet AMD progression but are not free from complications. (-)-Epigallocatechin-3-gallate (EGCG) is an active compound of green tea, which exerts many beneficial effects in the retinal pigment epithelium and the neural retina. It has been reported to downregulate the VEGFA gene by suppressing its activators. The inhibition of mitogen-activated protein kinases 1 and 3 (MAPK1 and MAPK3) may lie behind the antiangiogenic action of EGCG mediated by VEGFA. EGCG exerts protective effects against UV-induced damage to retinal cells and improves dysfunctional autophagy. EGCG may also interact with the mechanistic target rapamycin (MTOR) and unc-51-like autophagy activating kinase (ULK1) to modulate the interplay between autophagy and apoptosis. Several other studies report beneficial effects of EGCG on the retina that may be related to wet AMD. Therefore, controlled clinical trials are needed to verify whether diet supplementation with EGCG or green tea consumption may improve the results of anti-VEGFA therapy in wet AMD.
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Affiliation(s)
- Janusz Blasiak
- Department of Molecular Genetics, Faculty of Biology and Environmental Protection, University of Lodz, 90-236 Lodz, Poland
| | - Jan Chojnacki
- Department of Clinical Nutrition and Gastroenterological Diagnostics, Medical University of Lodz, 90-647 Lodz, Poland; (J.C.); (C.C.)
| | - Joanna Szczepanska
- Department of Pediatric Dentistry, Medical University of Lodz, 92-217 Lodz, Poland; (J.S.); (E.P.)
| | - Michal Fila
- Department of Developmental Neurology and Epileptology, Polish Mother’s Memorial Hospital Research Institute, 93-338 Lodz, Poland;
| | - Cezary Chojnacki
- Department of Clinical Nutrition and Gastroenterological Diagnostics, Medical University of Lodz, 90-647 Lodz, Poland; (J.C.); (C.C.)
| | - Kai Kaarniranta
- Department of Ophthalmology, University of Eastern Finland, 70210 Kuopio, Finland;
- Department of Ophthalmology, Kuopio University Hospital, 70210 Kuopio, Finland
| | - Elzbieta Pawlowska
- Department of Pediatric Dentistry, Medical University of Lodz, 92-217 Lodz, Poland; (J.S.); (E.P.)
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Sun M, Yu T, Zhao J, Zhu X, Xin W, Zhang F, Zhang L. Role of flavonoids in age-related macular degeneration. Biomed Pharmacother 2023; 159:114259. [PMID: 36652737 DOI: 10.1016/j.biopha.2023.114259] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Revised: 01/11/2023] [Accepted: 01/14/2023] [Indexed: 01/18/2023] Open
Abstract
A common eye disorder known as age-related macular degeneration (AMD) eventually results in blindness and vision loss. AMD has a complicated and poorly understood aetiology. The main pathological processes associated with AMD include oxidative damage, inflammation, and neovascularization. Flavonoids are naturally occurring bioactive substances with extensive distribution and antioxidant, anti-inflammatory, and neovascularization inhibitory properties. Several in vitro and in vivo AMD-related models pertinent to vision and this ocular ailment have been used to assess the mechanisms of action of various flavonoids. This article will discuss the research progress of flavonoids in AMD, especially the characteristics and mechanism of flavonoids in treating AMD.
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Affiliation(s)
- Mengmeng Sun
- Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, School of Pharmacy, Yantai University, Yantai 264005, PR China
| | - Tao Yu
- Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, School of Pharmacy, Yantai University, Yantai 264005, PR China
| | - Jianing Zhao
- Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, School of Pharmacy, Yantai University, Yantai 264005, PR China
| | - Xuan Zhu
- Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, School of Pharmacy, Yantai University, Yantai 264005, PR China
| | - Wenyu Xin
- Key Laboratory of Prescription Effect and Clinical Evaluation of State Administration of Traditional Chinese Medicine of China, School of Pharmacy, Binzhou Medical University, Yantai 264003, PR China.
| | - Fenglan Zhang
- Yantai Yuhuangding Hospital, The Affiliated Hospital of Qingdao University, Yantai 264000, PR China.
| | - Leiming Zhang
- Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, School of Pharmacy, Yantai University, Yantai 264005, PR China.
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Zhao B, Zhu L, Ye M, Lou X, Mou Q, Hu Y, Zhang H, Zhao Y. Oxidative stress and epigenetics in ocular vascular aging: an updated review. Mol Med 2023; 29:28. [PMID: 36849907 PMCID: PMC9972630 DOI: 10.1186/s10020-023-00624-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2022] [Accepted: 02/16/2023] [Indexed: 03/01/2023] Open
Abstract
Vascular aging is an inevitable process with advancing age, which plays a crucial role in the pathogenesis of cardiovascular and microvascular diseases. Diabetic retinopathy (DR) and age-related macular degeneration (AMD), characterized by microvascular dysfunction, are the common causes of irreversible blindness worldwide, however there is still a lack of effective therapeutic strategies for rescuing the visual function. In order to develop novel treatments, it is essential to illuminate the pathological mechanisms underlying the vascular aging during DR and AMD progression. In this review, we have summarized the recent discoveries of the effects of oxidative stress and epigenetics on microvascular degeneration, which could provide potential therapeutic targets for DR and AMD.
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Affiliation(s)
- Bowen Zhao
- Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Lijia Zhu
- Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Meng Ye
- Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Xiaotong Lou
- Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Qianxue Mou
- Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Yuanyuan Hu
- Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Hong Zhang
- Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
| | - Yin Zhao
- Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
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Yadav G, Narayanan R, Hathibelagal AR. Chromatic and flicker threshold changes in age-related macular degeneration following anti-VEGF treatment. Clin Exp Optom 2021; 105:313-319. [PMID: 33941047 DOI: 10.1080/08164622.2021.1916384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
Clinical relevance: Red-green chromatic sensitivity and photopic (cone-mediated) flicker sensitivity showed marked improvement after anti-VEGF treatment. The use of flicker and chromatic sensitivities as potential functional tests to monitor treatment outcomes in age-related macular degeneration highlights the clinical importance.Background: High-contrast visual acuity (VA) is not a sensitive clinical marker in the management of age-related macular degeneration (AMD). Therefore, flicker and chromatic sensitivity changes were assessed following anti-VEGF treatment in subjects with neovascular AMD.Methods: Subjects diagnosed with neovascular AMD were recruited. VA was measured using a COMPlog chart. Flicker (in central 5°) and chromatic thresholds (red-green and yellow-blue) were measured using Flicker-plus test and Colour Assessment and Diagnosis (CAD) tests, respectively. Baseline thresholds and foveal thickness were measured on the same day, just before anti-VEGF injection delivery and 5 weeks ± 5 days later.Results: Thirteen subjects (8 males, 5 females) with a mean age of 67.5 ± 8.2 years completed the study. Median VA was not significantly different post-treatment (0.57 logMAR [~6/22: Snellen equivalent], IQR: 0.33) compared to baseline (0.56 logMAR, IQR: 0.33), Wilcoxon matched-pair test, p = 0.55). Median Red-Green thresholds improved significantly post-treatment (22.15 CAD units, IQR: 26.06, n = 9), compared to baseline (24.24 CAD units, IQR: 26.21, p = 0.02). Median photopic and mesopic FMT did not show significant change post treatment compared to baseline (p > 0.01, statistical significance of p-value corrected for multiple comparisons was set to 0.01). Similarly, the foveal thickness was not significantly different at post-treatment visit than baseline (p = 0.53).Conclusion: Red/green sensitivity recovered better than yellow/blue sensitivity, thus, providing insight into recovery mechanisms in AMD and usefulness of these tests as clinical markers in the management of AMD.
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Affiliation(s)
- Gayatri Yadav
- Brien Holden Institute of Optometry and Vision Science, L. V. Prasad Eye Institute, Hyderabad, India
| | - Raja Narayanan
- Smt Kanuri Santhamma Centre for Vitreoretinal Diseases, L. V. Prasad Eye Institute, Hyderabad, India
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Trinh M, Kalloniatis M, Nivison-Smith L. Radial Peripapillary Capillary Plexus Sparing and Underlying Retinal Vascular Impairment in Intermediate Age-Related Macular Degeneration. Invest Ophthalmol Vis Sci 2021; 62:2. [PMID: 33792619 PMCID: PMC8024775 DOI: 10.1167/iovs.62.4.2] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
Purpose To examine location-specific retinal vascular changes in intermediate age-related macular degeneration (iAMD) using age-matched, high-density en face optical coherence tomography angiography (OCTA) cluster analysis. Methods En face OCTA images of the 6 × 6 mm macular area were retrospectively acquired from 60 iAMD eyes and 60 age-matched normal eyes and then subdivided into 126 × 126 (47.62 × 47.62 µm) grids within the superficial and deep vascular complex. Grid-wise vessel perfusion (VP) were compared between iAMD and normal eyes from the corresponding 10-yearly age cohort, forming difference plots. Difference plots were further separated by normative topographical map spatial clusters (C1-6), derived from normaldatabase eyes (n = 236, 20–81 years old). Results Overall difference plots showed decreased VP in the superficial (−12.19%) and deep vascular complex (−6.44%) of iAMD compared to normal eyes (P < 0.0001 both comparisons). Cluster-based difference plots highlighted nonuniform changes in the superficial vascular complex, with sparing of VP at the nasal macula (corresponding to the radial peripapillary capillary plexus) versus decreased VP toward the temporal macula and foveal avascular zone (FAZ) (C1–6 all comparisons P < 0.0001, except C1 vs. C2P > 0.99 and C4 vs. C5P = 0.11). The deep vascular complex displayed diffusely decreased VP, greater at the FAZ (P < 0.0001). Conclusions High-density en face OCTA cluster analysis suggests relative sparing of the radial peripapillary capillary plexus and impairment of underlying retinal vasculature, supporting potential anterograde transsynaptic degeneration in iAMD. These location-specific data may better guide future diagnostic and management protocol of iAMD.
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Affiliation(s)
- Matt Trinh
- Centre for Eye Health, University of New South Wales, Sydney, Australia.,School of Optometry and Vision Science, University of New South Wales, Sydney, Australia
| | - Michael Kalloniatis
- Centre for Eye Health, University of New South Wales, Sydney, Australia.,School of Optometry and Vision Science, University of New South Wales, Sydney, Australia
| | - Lisa Nivison-Smith
- Centre for Eye Health, University of New South Wales, Sydney, Australia.,School of Optometry and Vision Science, University of New South Wales, Sydney, Australia
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Gao L, Wang J, You Q, Guo Y, Flaxel CJ, Hwang TS, Huang D, Jia Y, Bailey ST. Plexus-specific retinal capillary avascular area in exudative age-related macular degeneration with projection-resolved OCT angiography. Br J Ophthalmol 2020; 106:719-723. [PMID: 33355172 DOI: 10.1136/bjophthalmol-2020-317562] [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: 07/24/2020] [Revised: 12/02/2020] [Accepted: 12/08/2020] [Indexed: 11/04/2022]
Abstract
OBJECTIVE To detect the plexus-specific retinal capillary avascular area in exudative age-related macular degeneration (EAMD) with projection-resolved optical coherence tomography angiography (PR-OCTA). METHODS AND ANALYSIS In this prospective cross-sectional single centre study, eyes with treatment-naïve EAMD underwent macular 3×3 mm OCTA with AngioVue system. OCTA scans were analysed and processed including three-dimensional projection artefact removal, retinal layer semi-automated segmentation and en face angiogram generation. Automated quantification of extrafoveal (excluding the central 1 mm circle) avascular area (EAA) were calculated on projection-resolved superficial vascular complex (SVC), intermediate capillary plexus (ICP) and deep capillary plexus (DCP), respectively. RESULTS Nineteen eyes with EAMD and 19 age-matched healthy control eyes were included. There was no significant difference between the EAMD and control eyes in terms of age, sex, axial length and mean ocular perfusion pressure (all p>0.05). Compared with control eyes, EAMD eyes had significantly larger EAA in SVC (median 0.125 vs 0.059 mm2, p=0.006), ICP (0.016 vs 0.000 mm2, p=0.004) and DCP (0.033 vs 0.000 mm2, p<0.001). CONCLUSION PR-OCTA showed that EAMD is associated with focal avascular area in all the three retinal vascular plexuses.
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Affiliation(s)
- Liqin Gao
- Ophthalmology, Beijing Tongren Eye Center, Beijing, China
| | - Jie Wang
- Ophthalmology, Casey Eye Institute, Oregon Health & Science University, Portland, Oregon, USA
| | - Qisheng You
- Ophthalmology, Casey Eye Institute, Oregon Health & Science University, Portland, Oregon, USA
| | - Yukun Guo
- Ophthalmology, Casey Eye Institute, Oregon Health & Science University, Portland, Oregon, USA
| | - Christina J Flaxel
- Ophthalmology, Casey Eye Institute, Oregon Health & Science University, Portland, Oregon, USA
| | - Thomas S Hwang
- Ophthalmology, Casey Eye Institute, Oregon Health & Science University, Portland, Oregon, USA
| | - David Huang
- Ophthalmology, Casey Eye Institute, Oregon Health & Science University, Portland, Oregon, USA
| | - Yali Jia
- Ophthalmology, Casey Eye Institute, Oregon Health & Science University, Portland, Oregon, USA
| | - Steven T Bailey
- Ophthalmology, Casey Eye Institute, Oregon Health & Science University, Portland, Oregon, USA
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7
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Xu J, Tu Y, Wang Y, Xu X, Sun X, Xie L, Zhao Q, Guo Y, Gu Y, Du J, Du S, Zhu M, Song E. Prodrug of epigallocatechin-3-gallate alleviates choroidal neovascularization via down-regulating HIF-1α/VEGF/VEGFR2 pathway and M1 type macrophage/microglia polarization. Biomed Pharmacother 2019; 121:109606. [PMID: 31743875 DOI: 10.1016/j.biopha.2019.109606] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Revised: 10/01/2019] [Accepted: 10/26/2019] [Indexed: 10/25/2022] Open
Abstract
Age-related macular degeneration (AMD) is a leading cause of vision loss in the elderly and is attributed to choroidal neovascularization (CNV), which is a feature of wet AMD. The hypoxia-inducible factor-1α (HIF-1α)/vascular endothelial growth factor (VEGF)/VEGF receptor 2 (VEGFR2) pathway contributes to the pathogenesis of CNV. M1-type macrophages/microglia secrete interleukin-6 (IL-6) and tumor necrosis factor α (TNF-α), facilitating the development of CNV. Epigallocatechin-3-gallate (EGCG) is a kind of polyphenol in green tea that exerts anti-inflammatory and antiangiogenic effects. In this study, a prodrug of EGCG (pro-EGCG) alleviated mouse laser-induced CNV leakage and reduced CNV area by down-regulating HIF-1α/VEGF/VEGFR2 pathway; M1-type macrophage/microglia polarization; as well as endothelial cell viability, proliferation, migration and tube formation, indicating a novel potential therapy for AMD.
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Affiliation(s)
- Jiaowen Xu
- Department of Ophthalmology, The Second Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China
| | - Yuanyuan Tu
- Department of Ophthalmology, Lixiang Eye Hospital of Soochow University, Suzhou, Jiangsu, China
| | - Ying Wang
- Department of Ophthalmology, Lixiang Eye Hospital of Soochow University, Suzhou, Jiangsu, China; Department of Ophthalmology, Suzhou Municipal Hospital, The Affiliated Suzhou Hospital of Nanjing Medical University, Suzhou, Jiangsu, China
| | - Xun Xu
- Shanghai Key Laboratory of Ocular Fundus Disease, Shanghai, China; Department of Ophthalmology, Shanghai First People's Hospital, School of Medicine, Shanghai JiaoTong University, Shanghai, China
| | - Xiaodong Sun
- Shanghai Key Laboratory of Ocular Fundus Disease, Shanghai, China; Department of Ophthalmology, Shanghai First People's Hospital, School of Medicine, Shanghai JiaoTong University, Shanghai, China
| | - Laiqing Xie
- Department of Ophthalmology, The Second Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China
| | - Qingliang Zhao
- Department of Ophthalmology, Lixiang Eye Hospital of Soochow University, Suzhou, Jiangsu, China
| | - Yang Guo
- Department of Ophthalmology, The Second Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China
| | - Yonghui Gu
- Department of Ophthalmology, Suzhou Municipal Hospital, The Affiliated Suzhou Hospital of Nanjing Medical University, Suzhou, Jiangsu, China
| | - Jingxia Du
- Department of Ophthalmology, The Second Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China
| | - Shu Du
- Department of Ophthalmology, Lixiang Eye Hospital of Soochow University, Suzhou, Jiangsu, China
| | - Manhui Zhu
- Department of Ophthalmology, Lixiang Eye Hospital of Soochow University, Suzhou, Jiangsu, China.
| | - E Song
- Department of Ophthalmology, Lixiang Eye Hospital of Soochow University, Suzhou, Jiangsu, China.
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8
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Linsenmeier RA, Zhang HF. Retinal oxygen: from animals to humans. Prog Retin Eye Res 2017; 58:115-151. [PMID: 28109737 DOI: 10.1016/j.preteyeres.2017.01.003] [Citation(s) in RCA: 148] [Impact Index Per Article: 21.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Revised: 01/13/2017] [Accepted: 01/17/2017] [Indexed: 10/20/2022]
Abstract
This article discusses retinal oxygenation and retinal metabolism by focusing on measurements made with two of the principal methods used to study O2 in the retina: measurements of PO2 with oxygen-sensitive microelectrodes in vivo in animals with a retinal circulation similar to that of humans, and oximetry, which can be used non-invasively in both animals and humans to measure O2 concentration in retinal vessels. Microelectrodes uniquely have high spatial resolution, allowing the mapping of PO2 in detail, and when combined with mathematical models of diffusion and consumption, they provide information about retinal metabolism. Mathematical models, grounded in experiments, can also be used to simulate situations that are not amenable to experimental study. New methods of oximetry, particularly photoacoustic ophthalmoscopy and visible light optical coherence tomography, provide depth-resolved methods that can separate signals from blood vessels and surrounding tissues, and can be combined with blood flow measures to determine metabolic rate. We discuss the effects on retinal oxygenation of illumination, hypoxia and hyperoxia, and describe retinal oxygenation in diabetes, retinal detachment, arterial occlusion, and macular degeneration. We explain how the metabolic measurements obtained from microelectrodes and imaging are different, and how they need to be brought together in the future. Finally, we argue for revisiting the clinical use of hyperoxia in ophthalmology, particularly in retinal arterial occlusions and retinal detachment, based on animal research and diffusion theory.
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Affiliation(s)
- Robert A Linsenmeier
- Biomedical Engineering Department, Northwestern University, 2145 Sheridan Road, Evanston 60208-3107, IL, USA; Neurobiology Department, Northwestern University, 2205 Tech Drive, Evanston 60208-3520, IL, USA; Ophthalmology Department, Northwestern University, 645 N. Michigan Ave, Suite 440, Chicago 60611, IL, USA.
| | - Hao F Zhang
- Biomedical Engineering Department, Northwestern University, 2145 Sheridan Road, Evanston 60208-3107, IL, USA; Ophthalmology Department, Northwestern University, 645 N. Michigan Ave, Suite 440, Chicago 60611, IL, USA.
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McKeague C, Margrain TH, Bailey C, Binns AM. Low-level night-time light therapy for age-related macular degeneration (ALight): study protocol for a randomized controlled trial. Trials 2014; 15:246. [PMID: 24965385 PMCID: PMC4227140 DOI: 10.1186/1745-6215-15-246] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2013] [Accepted: 05/23/2014] [Indexed: 12/11/2022] Open
Abstract
Background Age-related macular degeneration (AMD) is the leading cause of blindness among older adults in the developed world. The only treatments currently available, such as ranibizumab injections, are for neovascular AMD, which accounts for only 10 to 15% of people with the condition. Hypoxia has been implicated as one of the primary causes of AMD, and is most acute at night when the retina is most metabolically active. By increasing light levels at night, the metabolic requirements of the retina and hence the hypoxia will be considerably reduced. This trial seeks to determine whether wearing a light mask that emits a dim, green light during the night can prevent the progression of early AMD. Methods/design ALight is a Phase I/IIa, multicentre, randomized controlled trial. Sixty participants (55 to 88 years old) with early AMD in one eye and neovascular AMD (nAMD) in the fellow eye will be recruited from nAMD clinics. They will be randomized (in the ratio 1:1), either to receive the intervention or to be in the untreated control group, stratified according to risk of disease progression. An additional 40 participants with healthy retinal appearance, or early AMD only, will be recruited for a baseline cross-sectional analysis. The intervention is an eye mask that emits a dim green light to illuminate the retina through closed eyelids at night. This is designed to reduce the metabolic activity of the retina, thereby reducing the potential risk of hypoxia. Participants will wear the mask every night for 12 months. Ophthalmologists carrying out monthly assessments will be masked to the treatment group, but participants will be aware of their treatment group. The primary outcome measure is the proportion of people who show disease progression during the trial period in the eye with early AMD. A co-primary outcome measure is the rate of retinal adaptation. As this is a trial of a CE-marked device for an off-label indication, a further main aim of this trial is to assess safety of the mask in the cohort of participants with AMD. Trial registration International Standard Randomised Controlled Trials Register: ISRCTN82148651
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Affiliation(s)
| | | | | | - Alison M Binns
- School of Optometry and Vision Sciences, Cardiff University, Cardiff CF24 4 LU, UK.
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Stefanova NA, Zhdankina AA, Fursova AZ, Kolosova NG. Potential of melatonin for prevention of age-related macular degeneration: Experimental study. ADVANCES IN GERONTOLOGY 2013. [DOI: 10.1134/s2079057013040073] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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11
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Burgansky-Eliash Z, Barash H, Nelson D, Grinvald A, Sorkin A, Loewenstein A, Barak A. Retinal Blood Flow Velocity in Patients with Age-Related Macular Degeneration. Curr Eye Res 2013; 39:304-11. [DOI: 10.3109/02713683.2013.840384] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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Saprunova VB, Lelekova MA, Kolosova NG, Bakeeva LE. SkQ1 slows development of age-dependent destructive processes in retina and vascular layer of eyes of wistar and OXYS rats. BIOCHEMISTRY (MOSCOW) 2012; 77:648-58. [PMID: 22817465 DOI: 10.1134/s0006297912060120] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We show the development of clearly pronounced age-related pathological changes in eye tissues of Wistar and OXYS rats. Photoreceptor cells were virtually absent in all OXYS rats in the age of 24 months. Massive accumulations of lipofuscin granules were detected in the pigmented epithelium cells. Flattening, overgrowing, and degradation of endothelial cells of choriocapillaries were also observed. Along with these changes, vessels without signs of degradation were detected in the pigmented epithelium. In 24-month-old Wistar rats these changes were local and were seen in only some of the animals. The mitochondria-targeted antioxidant SkQ1 (the rats were given SkQ1 daily with food at the dose of 250 nmol/kg for 5 months, starting from the age of 19 months) prevented the development of these pathological changes in both Wistar and OXYS rats. The data were subjected to mathematical processing and statistical analysis.
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Affiliation(s)
- V B Saprunova
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, 119234 Moscow, Russia.
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13
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He H, Zhang H, Li B, Li G, Wang Z. Blockade of the sonic hedgehog signalling pathway inhibits choroidal neovascularization in a laser-induced rat model. ACTA ACUST UNITED AC 2010; 30:659-65. [PMID: 21063852 DOI: 10.1007/s11596-010-0560-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2010] [Indexed: 10/18/2022]
Abstract
Sonic hedgehog (Shh) signaling has recently been shown to be involved in the pathological angiogenesis in response to tissue hypoxia and ischemic injury. Hypoxia/ischemia is considered to play an important role in the development of choroidal neovascularization (CNV). This study was aimed to examine the effect of blockade of the Shh signaling pathway on CNV and the underlying mechanism. A total of 64 male Brown-Norway (BN) rats were used in this study. One eye of each rat underwent laser photocoagulation. The other eye served as normal control. After the laser treatment, the 64 rats were divided into four groups (n=16 in each group): Blank control group, in which no intravitreal administration was given; cyclopamine group, recombinant Shh N-terminals protein (rShh) group and phosphate-buffered saline (PBS) group, in which cyclopamine (a Shh inhibitor), rShh (a Shh activator) and PBS were intravitreally injected into the laser-treated eyes respectively every other day for a total of four intravitreal injections immediately after the laser treatment. Fourteen days after the intravitreal administration, the changes of CNV-related variables, including positive CNV lesion percentage, CNV membrane area and CNV membrane thickness, were evaluated by fluorescein angiography, indocyanine green angiography and pathological examinations. The mRNA and protein expression of PTCH1, Gli1, HIF-1(α), VEGF and DLL4 in each group on 14 days of CNV model was detected by real-time quantitative PCR and western blot analysis, and the relationship between the Shh cascade and the HIF-1(α)-VEGF-DLL4 cascade in CNV was analyzed. The results showed that the CNV membrane area and the CNV membrane thickness were decreased by 62.5% and 41.9% in the cyclopamine group and increased by 85.7% and 64.3% in the rShh group in comparison to those in the blank control group (P<0.01 for each). There was no significant difference in the CNV membrane area and thickness between the blank control group and PBS group (P=0.102 and P=0.063, respectively). Real-time quantitative PCR revealed a 5.23-, 4.14-, 2.97-, 2.78- and 2.39-fold up-regulation of the mRNA expression of PTCH1, Gli1, HIF-1(α), VEGF and DLL4 genes in the laser-treated eyes compared with the normal control eyes in the control group. In the cyclopamine group, the mRNA and protein expression of Gli1, HIF-1(α), VEGF and DLL4 was significantly down-regulated (P<0.05 for each) while the expression of PTCH1 showed no significant changes at the mRNA (P=0.293) and protein level (P=0.304). The mRNA expression and protein expression (P=0.001 and P=0.021, respectively) of PTCH1, Gli1, HIF-1(α), VEGF and DLL4 was significantly increased in the rShh group when compared with the control group. The expression level of these genes was related to the severity of the CNV. It was concluded that intravitreal administration of cyclopamine can effectively inhibit the formation of laser-induced experimental CNV by down-regulating the expression of the HIF-1(α)-VEGF-DLL4 cascade in CNV. The Shh signaling pathway as an upstream signaling pathway of HIF-1(α)-VEGF-DLL4 cascade is implicated in the development of experimental CNV.
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Affiliation(s)
- Hua He
- Department of Ophthalmology, Huazhong University of Science and Technology, Wuhan, China.
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14
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Berrow EJ, Bartlett HE, Eperjesi F, Gibson JM. The electroretinogram: a useful tool for evaluating age-related macular disease? Doc Ophthalmol 2010; 121:51-62. [PMID: 20232109 DOI: 10.1007/s10633-010-9226-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2009] [Accepted: 03/02/2010] [Indexed: 10/19/2022]
Abstract
With an ageing population, the number of age-related macular disease (ARMD) cases will inevitably rise. This gives greater impetus for the need to identify the disease earlier and assess treatments to slow disease progression. Differing electroretinogram (ERG) modalities have been reviewed in relation to the objective assessment of retinal function in ARMD and for monitoring the effectiveness of clinical interventions. Conflicting results have been found with regard to the efficacy of ERG findings in the investigation of ARMD in previous years. The newer multifocal ERG paradigm provides spatial topographical information about retinal function in ARMD. It has shown promising results in monitoring effectiveness of clinical interventions and studies are continuing in this area. Better knowledge of retinal function in ARMD may lead to enhanced treatments at each phase of the disease.
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Affiliation(s)
- Emma J Berrow
- Ophthalmic Research Group, School of Life and Health Sciences, Aston University, Birmingham B4 7ET, United Kingdom.
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15
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Abstract
Inner retinal ischaemia is involved in the pathogenesis of major vision-threatening diseases such as retinal vein thrombosis, diabetic retinopathy and retinopathy of prematurity. However, the pathogenesis of inner retinal ischaemia has not been fully elucidated, which represents an impediment to the development and improvement of techniques to prevent and treat these diseases on a rational basis. This paper provides a comprehensive review of current knowledge of the pathophysiology of inner retinal ischaemia, including clinical, anatomical and physiological aspects of disease development. It is suggested that chronic inner retinal ischaemia caused by capillary occlusion may develop secondary to an increase in hydrostatic pressure in the vessels. Further knowledge of the pathophysiology of inner retinal ischaemia can be obtained by identifying the mechanisms that lead to increased hydrostatic pressure in the capillary bed and establishing the structural and functional basis for the different response patterns in the central and peripheral areas of the retina that develop secondary to this increased hydrostatic pressure. Further elucidation of these unknown response patterns requires both in vitro and in vivo studies of retinal vascular pathophysiology. It is conceivable that a more detailed knowledge of these response patterns may help in the design of new treatments for retinal ischaemia and its vision-threatening consequences.
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Affiliation(s)
- Toke Bek
- Department of Ophthalmology, Arhus University Hospital, Arhus, Denmark.
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