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Chucair-Elliott AJ, Ocañas SR, Pham K, Machalinski A, Plafker S, Stout MB, Elliott MH, Freeman WM. Age- and sex- divergent translatomic responses of the mouse retinal pigmented epithelium. Neurobiol Aging 2024; 140:41-59. [PMID: 38723422 PMCID: PMC11173338 DOI: 10.1016/j.neurobiolaging.2024.04.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Revised: 04/22/2024] [Accepted: 04/23/2024] [Indexed: 05/18/2024]
Abstract
Aging is the main risk factor for age-related macular degeneration (AMD), a retinal neurodegenerative disease that leads to irreversible blindness, particularly in people over 60 years old. Retinal pigmented epithelium (RPE) atrophy is an AMD hallmark. Genome-wide chromatin accessibility, DNA methylation, and gene expression studies of AMD and control RPE demonstrate epigenomic/transcriptomic changes occur during AMD onset and progression. However, mechanisms by which molecular alterations of normal aging impair RPE function and contribute to AMD pathogenesis are unclear. Here, we specifically interrogate the RPE translatome with advanced age and across sexes in a novel RPE reporter mouse model. We find differential age- and sex- associated transcript expression with overrepresentation of pathways related to inflammation in the RPE. Concordant with impaired RPE function, the phenotypic changes in the aged translatome suggest that aged RPE becomes immunologically active, in both males and females, with some sex-specific signatures, which supports the need for sex representation for in vivo studies.
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Affiliation(s)
- Ana J Chucair-Elliott
- Genes & Human Disease Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA.
| | - Sarah R Ocañas
- Genes & Human Disease Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - Kevin Pham
- Genes & Human Disease Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - Adeline Machalinski
- Genes & Human Disease Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - Scott Plafker
- Aging & Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - Michael B Stout
- Aging & Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - Michael H Elliott
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA; Department of Ophthalmology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Willard M Freeman
- Genes & Human Disease Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA; Oklahoma City Veterans Affairs Medical Center, Oklahoma City, OK, USA.
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2
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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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Campbell JM, Gosnell M, Agha A, Handley S, Knab A, Anwer AG, Bhargava A, Goldys EM. Label-Free Assessment of Key Biological Autofluorophores: Material Characteristics and Opportunities for Clinical Applications. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024:e2403761. [PMID: 38775184 DOI: 10.1002/adma.202403761] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2024] [Revised: 05/04/2024] [Indexed: 06/13/2024]
Abstract
Autofluorophores are endogenous fluorescent compounds that naturally occur in the intra and extracellular spaces of all tissues and organs. Most have vital biological functions - like the metabolic cofactors NAD(P)H and FAD+, as well as the structural protein collagen. Others are considered to be waste products - like lipofuscin and advanced glycation end products - which accumulate with age and are associated with cellular dysfunction. Due to their natural fluorescence, these materials have great utility for enabling non-invasive, label-free assays with direct ties to biological function. Numerous technologies, with different advantages and drawbacks, are applied to their assessment, including fluorescence lifetime imaging microscopy, hyperspectral microscopy, and flow cytometry. Here, the applications of label-free autofluorophore assessment are reviewed for clinical and health-research applications, with specific attention to biomaterials, disease detection, surgical guidance, treatment monitoring, and tissue assessment - fields that greatly benefit from non-invasive methodologies capable of continuous, in vivo characterization.
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Affiliation(s)
- Jared M Campbell
- Australian Research Council Centre of Excellence for Nanoscale BioPhotonics, Graduate School of Biomedical Engineering, University of New South Wales, Sydney, NSW, 2033, Australia
| | | | - Adnan Agha
- Australian Research Council Centre of Excellence for Nanoscale BioPhotonics, Graduate School of Biomedical Engineering, University of New South Wales, Sydney, NSW, 2033, Australia
| | - Shannon Handley
- Australian Research Council Centre of Excellence for Nanoscale BioPhotonics, Graduate School of Biomedical Engineering, University of New South Wales, Sydney, NSW, 2033, Australia
| | - Aline Knab
- Australian Research Council Centre of Excellence for Nanoscale BioPhotonics, Graduate School of Biomedical Engineering, University of New South Wales, Sydney, NSW, 2033, Australia
| | - Ayad G Anwer
- Australian Research Council Centre of Excellence for Nanoscale BioPhotonics, Graduate School of Biomedical Engineering, University of New South Wales, Sydney, NSW, 2033, Australia
| | - Akanksha Bhargava
- Australian Research Council Centre of Excellence for Nanoscale BioPhotonics, Graduate School of Biomedical Engineering, University of New South Wales, Sydney, NSW, 2033, Australia
| | - Ewa M Goldys
- Australian Research Council Centre of Excellence for Nanoscale BioPhotonics, Graduate School of Biomedical Engineering, University of New South Wales, Sydney, NSW, 2033, Australia
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Kunala K, Tang JAH, Bowles Johnson KE, Huynh KT, Parkins K, Kim HJ, Yang Q, Sparrow JR, Hunter JJ. Near Infrared Autofluorescence Lifetime Imaging of Human Retinal Pigment Epithelium Using Adaptive Optics Scanning Light Ophthalmoscopy. Invest Ophthalmol Vis Sci 2024; 65:27. [PMID: 38758638 PMCID: PMC11107951 DOI: 10.1167/iovs.65.5.27] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Accepted: 04/23/2024] [Indexed: 05/19/2024] Open
Abstract
Purpose To demonstrate the first near-infrared adaptive optics fluorescence lifetime imaging ophthalmoscopy (NIR-AOFLIO) measurements in vivo of the human retinal pigment epithelial (RPE) cellular mosaic and to visualize lifetime changes at different retinal eccentricities. Methods NIR reflectance and autofluorescence were captured using a custom adaptive optics scanning light ophthalmoscope in 10 healthy subjects (23-64 years old) at seven eccentricities and in two eyes with retinal abnormalities. Repeatability was assessed across two visits up to 8 weeks apart. Endogenous retinal fluorophores and hydrophobic whole retinal extracts of Abca4-/- pigmented and albino mice were imaged to probe the fluorescence origin of NIR-AOFLIO. Results The RPE mosaic was resolved at all locations in five of seven younger subjects (<35 years old). The mean lifetime across near-peripheral regions (8° and 12°) was longer compared to near-foveal regions (0° and 2°). Repeatability across two visits showed moderate to excellent correlation (intraclass correlation: 0.88 [τm], 0.75 [τ1], 0.65 [τ2], 0.98 [a1]). The mean lifetime across drusen-containing eyes was longer than in age-matched healthy eyes. Fluorescence was observed in only the extracts from pigmented Abca4-/- mouse. Conclusions NIR-AOFLIO was repeatable and allowed visualization of the RPE cellular mosaic. An observed signal in only the pigmented mouse extract infers the fluorescence signal originates predominantly from melanin. Variations observed across the retina with intermediate age-related macular degeneration suggest NIR-AOFLIO may act as a functional measure of a biomarker for in vivo monitoring of early alterations in retinal health.
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Affiliation(s)
- Karteek Kunala
- Center for Visual Science, University of Rochester, Rochester, New York, United States
- Byers Eye Institute, Stanford University, Palo Alto, California, United States
| | - Janet A. H. Tang
- Center for Visual Science, University of Rochester, Rochester, New York, United States
- The Institute of Optics, University of Rochester, Rochester, New York, United States
| | - Kristen E. Bowles Johnson
- Center for Visual Science, University of Rochester, Rochester, New York, United States
- Flaum Eye Institute, University of Rochester, Rochester, New York, United States
- School of Optometry, Indiana University, Bloomington, Indiana, United States
| | - Khang T. Huynh
- Center for Visual Science, University of Rochester, Rochester, New York, United States
- Department of Biomedical Engineering, University of Rochester, Rochester, New York, United States
- Herbert Wertheim School of Optometry & Vision Science, University of California, Berkeley, Berkeley, California, United States
| | - Keith Parkins
- Center for Visual Science, University of Rochester, Rochester, New York, United States
| | - Hye-Jin Kim
- College of Pharmacy, Keimyung University, Dalseo-gu, Daegu, South Korea
- Department of Ophthalmology, Columbia University Medical Center, New York, New York, United States
| | - Qiang Yang
- Center for Visual Science, University of Rochester, Rochester, New York, United States
| | - Janet R. Sparrow
- Department of Ophthalmology, Columbia University Medical Center, New York, New York, United States
| | - Jennifer J. Hunter
- Center for Visual Science, University of Rochester, Rochester, New York, United States
- Flaum Eye Institute, University of Rochester, Rochester, New York, United States
- School of Optometry and Vision Science, University of Waterloo, Waterloo, Ontario, Canada
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Obasanmi G, Uppal M, Cui JZ, Xi J, Ju MJ, Song J, To E, Li S, Khan W, Cheng D, Zhu J, Irani L, Samad I, Zhu J, Yoo HS, Aubert A, Stoddard J, Neuringer M, Granville DJ, Matsubara JA. Granzyme B degrades extracellular matrix and promotes inflammation and choroidal neovascularization. Angiogenesis 2024:10.1007/s10456-024-09909-9. [PMID: 38498232 DOI: 10.1007/s10456-024-09909-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Accepted: 02/11/2024] [Indexed: 03/20/2024]
Abstract
Age-related macular degeneration (AMD) is a common retinal neurodegenerative disease among the elderly. Neovascular AMD (nAMD), a leading cause of AMD-related blindness, involves choroidal neovascularization (CNV), which can be suppressed by anti-angiogenic treatments. However, current CNV treatments do not work in all nAMD patients. Here we investigate a novel target for AMD. Granzyme B (GzmB) is a serine protease that promotes aging, chronic inflammation and vascular permeability through the degradation of the extracellular matrix (ECM) and tight junctions. Extracellular GzmB is increased in retina pigment epithelium (RPE) and mast cells in the choroid of the healthy aging outer retina. It is further increased in donor eyes exhibiting features of nAMD and CNV. Here, we show in RPE-choroidal explant cultures that exogenous GzmB degrades the RPE-choroid ECM, promotes retinal/choroidal inflammation and angiogenesis while diminishing anti-angiogenic factor, thrombospondin-1 (TSP-1). The pharmacological inhibition of either GzmB or mast-cell degranulation significantly reduces choroidal angiogenesis. In line with our in vitro data, GzmB-deficiency reduces the extent of laser-induced CNV lesions and the age-related deterioration of electroretinogram (ERG) responses in mice. These findings suggest that targeting GzmB, a serine protease with no known endogenous inhibitors, may be a potential novel therapeutic approach to suppress CNV in nAMD.
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Affiliation(s)
- Gideon Obasanmi
- Department of Ophthalmology and Visual Sciences, UBC, Vancouver, BC, Canada
| | - Manjosh Uppal
- Department of Ophthalmology and Visual Sciences, UBC, Vancouver, BC, Canada
| | - Jing Z Cui
- Department of Ophthalmology and Visual Sciences, UBC, Vancouver, BC, Canada
| | - Jeanne Xi
- Department of Ophthalmology and Visual Sciences, UBC, Vancouver, BC, Canada
| | - Myeong Jin Ju
- Department of Ophthalmology and Visual Sciences, UBC, Vancouver, BC, Canada
- School of Biomedical Engineering, UBC, Vancouver, BC, Canada
| | - Jun Song
- School of Biomedical Engineering, UBC, Vancouver, BC, Canada
| | - Eleanor To
- Department of Ophthalmology and Visual Sciences, UBC, Vancouver, BC, Canada
| | - Siqi Li
- Department of Ophthalmology and Visual Sciences, UBC, Vancouver, BC, Canada
| | - Wania Khan
- Department of Ophthalmology and Visual Sciences, UBC, Vancouver, BC, Canada
| | - Darian Cheng
- Department of Ophthalmology and Visual Sciences, UBC, Vancouver, BC, Canada
| | - John Zhu
- Department of Ophthalmology and Visual Sciences, UBC, Vancouver, BC, Canada
| | - Lyden Irani
- Department of Ophthalmology and Visual Sciences, UBC, Vancouver, BC, Canada
| | - Isa Samad
- Department of Ophthalmology and Visual Sciences, UBC, Vancouver, BC, Canada
| | - Julie Zhu
- Department of Ophthalmology and Visual Sciences, UBC, Vancouver, BC, Canada
| | - Hyung-Suk Yoo
- Department of Ophthalmology and Visual Sciences, UBC, Vancouver, BC, Canada
| | - Alexandre Aubert
- International Collaboration On Repair Discoveries (ICORD), Vancouver Coastal Health Research Institute, University of British Columbia (UBC), Vancouver, BC, Canada
- Department of Pathology and Laboratory Medicine, UBC, Vancouver, BC, Canada
| | | | | | - David J Granville
- International Collaboration On Repair Discoveries (ICORD), Vancouver Coastal Health Research Institute, University of British Columbia (UBC), Vancouver, BC, Canada
- Department of Pathology and Laboratory Medicine, UBC, Vancouver, BC, Canada
| | - Joanne A Matsubara
- Department of Ophthalmology and Visual Sciences, UBC, Vancouver, BC, Canada.
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6
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Liu X, Lv X, Ji T, Hu H, Chang L. Gynostemma pentaphyllum Makino extract induces hair growth and exhibits an anti-graying effect via multiple mechanisms. J Cosmet Dermatol 2024; 23:648-657. [PMID: 37649302 DOI: 10.1111/jocd.15963] [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: 05/22/2023] [Revised: 07/17/2023] [Accepted: 08/07/2023] [Indexed: 09/01/2023]
Abstract
BACKGROUND In traditional Asian medicine, Gynostemma pentaphyllum Makino leaf extract (Gp) is used to treat aging, metabolic syndrome, diabetes, and neurodegenerative diseases. Hair loss and hair-graying are common phenomena that haunt everyone. However, whether Gp activities on inhibition of hair loss and getting gray have been rarely studied. AIM Study the Gp activity and mechanism by in vivo and in vitro experiments to explore its application on hair health. METHODS In the present study, we determined the effects of Gp on the expression of hair growth-related genes and proliferation of human dermal papilla cells (hDPCs). Furthermore, Gp was topically applied to the hair-shaved skin of male C57BL/6 mice, and the histological profile of the skin was studied. Because emotional stress may lead to melanocyte disappearance, norepinephrine-exposed mice B16 melanocytes were treated with Gp to elucidate the anti-hair graying capacity of Gp in response to this stress type. RESULTS Gp stimulated the proliferation of hDPCs and the Wnt signaling pathways associated with hair growth; furthermore, the expression of the hair loss-related gene transforming growth factor-β1 was suppressed. Gp treatment significantly increased the size of hair follicles in the treated mice and stimulated them. Moreover, Gp not only increased melanin synthesis but also tyrosinase activity in B16 cells. Quantitative real-time polymerase chain reaction revealed that Gp increased melanin synthesis by increasing the expression of tyrosine-related protein-1, tyrosine-related protein-2, tyrosinase, and microphthalmia-associated transcription factor. CONCLUSION Our study provides preclinical evidence regarding the potential of Gp as a promising hair growth and anti-graying agent.
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Affiliation(s)
- Xiaojin Liu
- Anhui Provincial Key Laboratory of Molecular Enzymology and Mechanism of Major Diseases, College of Life Sciences, Anhui Normal University, Wuhu, China
- Anhui Provincial Key Laboratory of the Conservation and Exploitation of Biological Resources, College of Life Sciences, Anhui Normal University, Wuhu, China
| | - Xiaobing Lv
- Anhui Provincial Key Laboratory of Molecular Enzymology and Mechanism of Major Diseases, College of Life Sciences, Anhui Normal University, Wuhu, China
- Anhui Provincial Key Laboratory of the Conservation and Exploitation of Biological Resources, College of Life Sciences, Anhui Normal University, Wuhu, China
| | - Tiancheng Ji
- Anhui Provincial Key Laboratory of Molecular Enzymology and Mechanism of Major Diseases, College of Life Sciences, Anhui Normal University, Wuhu, China
- Anhui Provincial Key Laboratory of the Conservation and Exploitation of Biological Resources, College of Life Sciences, Anhui Normal University, Wuhu, China
| | - Haoya Hu
- Anhui Provincial Key Laboratory of Molecular Enzymology and Mechanism of Major Diseases, College of Life Sciences, Anhui Normal University, Wuhu, China
- Anhui Provincial Key Laboratory of the Conservation and Exploitation of Biological Resources, College of Life Sciences, Anhui Normal University, Wuhu, China
| | - Lei Chang
- Anhui Provincial Key Laboratory of Molecular Enzymology and Mechanism of Major Diseases, College of Life Sciences, Anhui Normal University, Wuhu, China
- Anhui Provincial Key Laboratory of the Conservation and Exploitation of Biological Resources, College of Life Sciences, Anhui Normal University, Wuhu, China
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Ahn SM, Song MS, Togloom A, Oh J. Quantification of choroidal hyperreflective layer: A swept-source optical coherence tomography study. PLoS One 2023; 18:e0294476. [PMID: 38019820 PMCID: PMC10686441 DOI: 10.1371/journal.pone.0294476] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Accepted: 11/02/2023] [Indexed: 12/01/2023] Open
Abstract
PURPOSE To investigate variation in reflectivity of choroidal layers in normal eyes. METHODS From the swept-source optical coherence tomography database, we retrospectively included eyes with a normal fundus. Choroidal reflectivity was measured on the horizontal and vertical B-scan optical coherence tomography images. The optical barrier of the choroid was defined as the first hill in the middle of the reflectance graph from the retinal pigment epithelium-Bruch's membrane complex to the chorioscleral junction. RESULTS The optical barrier of the choroid was identified in 91 eyes of 91 individuals. The amplitude of peak reflectivity of the optical barrier of the choroid at macular center (142.85 ± 15.04) was greater than those in superior (136.12 ± 14.08) or inferior macula (135.30 ± 16.13) (P = 0.028, P = 0.008, respectively). Latency between the peak of the retinal pigment epithelium-Bruch's membrane complex and the optical barrier of the choroid at macular center (48.11 ± 13.78 μm) was shorter than those in nasal macula (55.58 ± 19.21 μm) (P = 0.021). The amplitude of the peak reflectivity of the optical barrier of the choroid in the center negatively correlated with the latency between the retinal pigment epithelium-Bruch's membrane complex and the optical barrier of the choroid (P < 0.001). CONCLUSION An optical barrier exists in the inner choroid of the normal eye. Its depth depends on the location within the macula. Further studies are mandatory to evaluate variations in the barrier in the eyes with chorioretinal disease.
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Affiliation(s)
- So Min Ahn
- Department of Ophthalmology, Korea University College of Medicine, Seoul, South Korea
| | - Myung-Sun Song
- Department of Ophthalmology, Korea University College of Medicine, Seoul, South Korea
| | - Ariunaa Togloom
- Department of Ophthalmology, Korea University College of Medicine, Seoul, South Korea
| | - Jaeryung Oh
- Department of Ophthalmology, Korea University College of Medicine, Seoul, South Korea
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Abstract
The human retina is amenable to direct, noninvasive visualization using a wide array of imaging modalities. In the ∼140 years since the publication of the first image of the living human retina, there has been a continued evolution of retinal imaging technology. Advances in image acquisition and processing speed now allow real-time visualization of retinal structure, which has revolutionized the diagnosis and management of eye disease. Enormous advances have come in image resolution, with adaptive optics (AO)-based systems capable of imaging the retina with single-cell resolution. In addition, newer functional imaging techniques provide the ability to assess function with exquisite spatial and temporal resolution. These imaging advances have had an especially profound impact on the field of inherited retinal disease research. Here we will review some of the advances and applications of AO retinal imaging in patients with inherited retinal disease.
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Affiliation(s)
- Jacque L Duncan
- Department of Ophthalmology, University of California, San Francisco, California 94143-4081, USA
| | - Joseph Carroll
- Department of Ophthalmology & Visual Sciences, Medical College of Wisconsin Eye Institute, Milwaukee, Wisconsin 53226, USA
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9
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Riazi Esfahani P, Reddy AJ, Thomas J, Sommer DA, Nguyen A, Farasat V, Nawathey N, Bachir A, Brahmbhatt T, Patel R. An Analysis of the Usage of Retinal Imaging Technology in the Detection of Age-Related Macular Degeneration. Cureus 2023; 15:e40527. [PMID: 37461783 PMCID: PMC10350318 DOI: 10.7759/cureus.40527] [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] [Accepted: 06/16/2023] [Indexed: 07/20/2023] Open
Abstract
Age-related macular degeneration (AMD) is a disease that worsens the central vision of numerous individuals across the globe. Ensuring that patients are diagnosed accurately and that their symptoms are carefully monitored is essential to ensure that adequate care is delivered. To accomplish this objective, retinal imaging technology is necessary to assess the pathophysiology that is required to give an accurate diagnosis of AMD. The purpose of this review is to assess the ability of various retinal imaging technologies such as optical coherence tomography (OCT), color fundus retinal photography, fluorescein angiography, and fundus photography. The statistical methods that were conducted yielded results that suggested that using OCT in conjunction with other imaging technologies results in a higher detection of symptoms among patients that have AMD. Further investigation should be conducted to ascertain the validity of the conclusions that were stated within the review.
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Affiliation(s)
- Parsa Riazi Esfahani
- Department of Medicine, California University of Science and Medicine, Colton, USA
| | - Akshay J Reddy
- Department of Medicine, California University of Science and Medicine, Colton, USA
| | - Jack Thomas
- Department of Medicine, California University of Science and Medicine, Colton, USA
| | - Dillon A Sommer
- Department of Medicine, California University of Science and Medicine, Colton, USA
| | - Anna Nguyen
- Department of Medicine, California University of Science and Medicine, Colton, USA
| | | | - Neel Nawathey
- Department of Health Sciences, California Northstate University, Rancho Cordova, USA
| | - Alex Bachir
- Department of Medicine, Geisinger Commonwealth School of Medicine, Scranton, USA
| | - Telak Brahmbhatt
- Department of Health Sciences, California Northstate University, Rancho Cordova, USA
| | - Rakesh Patel
- Department of Internal Medicine, East Tennessee State University Quillen College of Medicine, Johnson City, USA
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10
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Gadallah MT, Mohamed AEA, Hefnawy A, Zidan H, El-banby G, Badawy SM. A Mathematical Model for Simulating Photoacoustic Signal Generation Process in Biological Tissues.. [DOI: 10.21203/rs.3.rs-2928563/v2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
Abstract
Abstract
Background: Biomedical photoacoustic imaging (PAI) is a hybrid imaging modality based on the laser-generated ultrasound waves due to the photoacoustic (PA) effect physical phenomenon that has been reported firstly by A. G. Bell in 1880. Numerical modeling-based simulation for the PA signal generation process in biological tissues helps researchers for decreasing error trials in-vitro and hence decreasing error rates for in-vivo experiments. Numerical modeling methods help in obtaining a rapid modeling procedure comparable to pure mathematics. However, if a proper simplified mathematical model can be founded before applying numerical modeling techniques, it will be a great advantage for the overall numerical model. Most scientific theories, equations, and assumptions, been proposed to mathematically model the complete PA signal generation and propagation process in biological tissues, are so complicated. Hence, the researchers, especially the beginners, will find a hard difficulty to explore and obtain a proper simplified mathematical model describing the process. That’s why this paper is introduced.
Methods: In this paper we have tried to simplify understanding for the biomedical PA wave’s generation and propagation process, deducing a simplified mathematical model for the whole process. The proposed deduced model is based on three steps: a- pulsed laser irradiance, b- diffusion of light through biological tissue, and c- acoustic pressure wave generation and propagation from the target tissue to the ultrasound transducer surface. COMSOL Multiphysics, which is founded due to the finite element method (FEM) numerical modeling principle, has been utilized to validate the proposed deduced mathematical model on a simulated biological tissue including a tumor inside.
Results and Conclusion: The time-dependent study been applied by COMSOL has assured that the proposed deduced mathematical model may be considered as a simplified, easy, and fast startup base for scientific researchers to numerically model and simulate biomedical PA signals’ generation and propagation process utilizing any proper software like COMSOL.
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11
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Gadallah MT, Mohamed AEA, Hefnawy A, Zidan H, El-banby G, Badawy SM. A Mathematical Model for Simulating Photoacoustic Signal Generation Process in Biological Tissues.. [DOI: 10.21203/rs.3.rs-2928563/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
Abstract
Abstract
Background
Biomedical photoacoustic imaging (PAI) is a hybrid imaging modality based on the laser-generated ultrasound waves due to the photoacoustic (PA) effect physical phenomenon that has been reported firstly by A. G. Bell in 1880. Numerical modeling based simulation for PA signal generation process in biological tissues helps researchers for decreasing error trials in-vitro and hence decreasing error rates for in-vivo experiments. Numerical modeling methods help in obtaining a rapid modeling procedure comparable to pure mathematics. However, if a proper simplified mathematical model can be founded before applying numerical modeling techniques, it will be a great advantage for the overall numerical model. More scientific theories, equations, and assumptions through the biomedical PA imaging research literature have been proposed trying to mathematically model the complete PA signal generation and propagation process in biological tissues. However, most of them have so complicated details. Hence, the researchers, especially the beginners, will find a hard difficulty to explore and obtain a proper simplified mathematical model describing the process. That’s why this paper is introduced.
Methods
In this paper we have tried to simplify understanding for the biomedical PA wave’s generation and propagation process, deducing a simplified mathematical model for the whole process. The proposed deduced model is based on three steps: a- pulsed laser irradiance, b- diffusion of light through biological tissue, and c- acoustic pressure wave generation and propagation from the target tissue to the ultrasound transducer surface.
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12
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Characterization of Spontaneous Melanization by Fluorescence Spectroscopy: A Basis for Analytical Application to Biological Substrates. BIOLOGY 2023; 12:biology12030433. [PMID: 36979125 PMCID: PMC10044826 DOI: 10.3390/biology12030433] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Revised: 03/07/2023] [Accepted: 03/10/2023] [Indexed: 03/16/2023]
Abstract
Melanin is present in various biological substrates where it may participate in several processes, from innate immunity to the still-unsolved opposite roles in antioxidant protection, including photoprotection and the related ability to interact with light. Melanin–light interaction has also been an important source of inspiration for the development of innovative bioengineering applications. These are based on melanin’s light-energy-absorption ability of its chemically and structurally complex components and precursors, and on the improvement in analytical and diagnostic procedures in biomedicine. In this regard, here, we characterized the fluorescence spectral properties of melanin and of its precursor L-tyrosine in an aqueous solution during spontaneous melanization. Besides the confirmation of the typical fluorescence-emission signature of melanin and L-tyrosine, we provide additional insights on both emission and excitation spectra recorded during melanization. On these bases, we performed a subsequent characterization on the aqueous extracts from two different melanin-containing biological substrates, namely hairs from a domestic black cat and eggs from the Asian tiger mosquito. The results from the mild extraction procedure, purposely applied to obtain only the soluble components, combined with fluorescence spectral analysis are expected to promote further investigation of the melanization processes, particularly in insects.
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13
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Nguyen T, Urrutia-Cabrera D, Wang L, Lees JG, Wang JH, Hung SS, Hewitt AW, Edwards TL, McLenachan S, Chen FK, Lim SY, Luu CD, Guymer R, Wong RC. Knockout of AMD-associated gene POLDIP2 reduces mitochondrial superoxide in human retinal pigment epithelial cells. Aging (Albany NY) 2023; 15:1713-1733. [PMID: 36795578 PMCID: PMC10085620 DOI: 10.18632/aging.204522] [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: 07/16/2022] [Accepted: 02/01/2023] [Indexed: 02/17/2023]
Abstract
Genetic and epidemiologic studies have significantly advanced our understanding of the genetic factors contributing to age-related macular degeneration (AMD). In particular, recent expression quantitative trait loci (eQTL) studies have highlighted POLDIP2 as a significant gene that confers risk of developing AMD. However, the role of POLDIP2 in retinal cells such as retinal pigment epithelium (RPE) and how it contributes to AMD pathology are unknown. Here we report the generation of a stable human RPE cell line ARPE-19 with POLDIP2 knockout using CRISPR/Cas, providing an in vitro model to investigate the functions of POLDIP2. We conducted functional studies on the POLDIP2 knockout cell line and showed that it retained normal levels of cell proliferation, cell viability, phagocytosis and autophagy. Also, we performed RNA sequencing to profile the transcriptome of POLDIP2 knockout cells. Our results highlighted significant changes in genes involved in immune response, complement activation, oxidative damage and vascular development. We showed that loss of POLDIP2 caused a reduction in mitochondrial superoxide levels, which is consistent with the upregulation of the mitochondrial superoxide dismutase SOD2. In conclusion, this study demonstrates a novel link between POLDIP2 and SOD2 in ARPE-19, which supports a potential role of POLDIP2 in regulating oxidative stress in AMD pathology.
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Affiliation(s)
- Tu Nguyen
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
- Ophthalmology, Department of Surgery, University of Melbourne, Melbourne, Victoria, Australia
| | - Daniel Urrutia-Cabrera
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
- Ophthalmology, Department of Surgery, University of Melbourne, Melbourne, Victoria, Australia
| | - Luozixian Wang
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
- Ophthalmology, Department of Surgery, University of Melbourne, Melbourne, Victoria, Australia
| | - Jarmon G. Lees
- O’Brien Institute Department, St Vincent’s Institute of Medical Research, Melbourne, Victoria, Australia
- Departments of Surgery and Medicine, University of Melbourne, Melbourne, Victoria, Australia
| | - Jiang-Hui Wang
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
- Ophthalmology, Department of Surgery, University of Melbourne, Melbourne, Victoria, Australia
| | - Sandy S.C. Hung
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
- Ophthalmology, Department of Surgery, University of Melbourne, Melbourne, Victoria, Australia
| | - Alex W. Hewitt
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
- Ophthalmology, Department of Surgery, University of Melbourne, Melbourne, Victoria, Australia
- Menzies Institute for Medical Research, School of Medicine, University of Tasmania, Hobart, Tasmania, Australia
| | - Thomas L. Edwards
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
- Ophthalmology, Department of Surgery, University of Melbourne, Melbourne, Victoria, Australia
| | - Sam McLenachan
- Centre for Ophthalmology and Visual Science (Incorporating Lions Eye Institute), The University of Western Australia, Department of Ophthalmology, Royal Perth Hospital, Perth, Western Australia, Australia
| | - Fred K. Chen
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
- Ophthalmology, Department of Surgery, University of Melbourne, Melbourne, Victoria, Australia
- Centre for Ophthalmology and Visual Science (Incorporating Lions Eye Institute), The University of Western Australia, Department of Ophthalmology, Royal Perth Hospital, Perth, Western Australia, Australia
| | - Shiang Y. Lim
- O’Brien Institute Department, St Vincent’s Institute of Medical Research, Melbourne, Victoria, Australia
- Departments of Surgery and Medicine, University of Melbourne, Melbourne, Victoria, Australia
| | - Chi D. Luu
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
- Ophthalmology, Department of Surgery, University of Melbourne, Melbourne, Victoria, Australia
| | - Robyn Guymer
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
- Ophthalmology, Department of Surgery, University of Melbourne, Melbourne, Victoria, Australia
| | - Raymond C.B. Wong
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
- Ophthalmology, Department of Surgery, University of Melbourne, Melbourne, Victoria, Australia
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14
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Arrigo A, Aragona E, Battaglia Parodi M, Bandello F. Quantitative approaches in multimodal fundus imaging: State of the art and future perspectives. Prog Retin Eye Res 2023; 92:101111. [PMID: 35933313 DOI: 10.1016/j.preteyeres.2022.101111] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Revised: 07/16/2022] [Accepted: 07/19/2022] [Indexed: 02/01/2023]
Abstract
When it first appeared, multimodal fundus imaging revolutionized the diagnostic workup and provided extremely useful new insights into the pathogenesis of fundus diseases. The recent addition of quantitative approaches has further expanded the amount of information that can be obtained. In spite of the growing interest in advanced quantitative metrics, the scientific community has not reached a stable consensus on repeatable, standardized quantitative techniques to process and analyze the images. Furthermore, imaging artifacts may considerably affect the processing and interpretation of quantitative data, potentially affecting their reliability. The aim of this survey is to provide a comprehensive summary of the main multimodal imaging techniques, covering their limitations as well as their strengths. We also offer a thorough analysis of current quantitative imaging metrics, looking into their technical features, limitations, and interpretation. In addition, we describe the main imaging artifacts and their potential impact on imaging quality and reliability. The prospect of increasing reliance on artificial intelligence-based analyses suggests there is a need to develop more sophisticated quantitative metrics and to improve imaging technologies, incorporating clear, standardized, post-processing procedures. These measures are becoming urgent if these analyses are to cross the threshold from a research context to real-life clinical practice.
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Affiliation(s)
- Alessandro Arrigo
- Department of Ophthalmology, IRCCS San Raffaele Scientific Institute, via Olgettina 60, 20132, Milan, Italy.
| | - Emanuela Aragona
- Department of Ophthalmology, IRCCS San Raffaele Scientific Institute, via Olgettina 60, 20132, Milan, Italy
| | - Maurizio Battaglia Parodi
- Department of Ophthalmology, IRCCS San Raffaele Scientific Institute, via Olgettina 60, 20132, Milan, Italy
| | - Francesco Bandello
- Department of Ophthalmology, IRCCS San Raffaele Scientific Institute, via Olgettina 60, 20132, Milan, Italy
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15
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Merkle CW, Augustin M, Harper DJ, Glösmann M, Baumann B. Degeneration of Melanin-Containing Structures Observed Longitudinally in the Eyes of SOD1-/- Mice Using Intensity, Polarization, and Spectroscopic OCT. Transl Vis Sci Technol 2022; 11:28. [PMID: 36259678 PMCID: PMC9587514 DOI: 10.1167/tvst.11.10.28] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
Purpose Melanin plays an important function in maintaining eye health, however there are few metrics that can be used to study retinal melanin content in vivo. Methods The slope of the spectral coefficient of variation (SSCoV) is a novel biomarker that measures chromophore concentration by analyzing the local divergence of spectral intensities using optical coherence tomography (OCT). This metric was validated in a phantom and applied in a longitudinal study of superoxide dismutase 1 knockout (SOD1−/−) mice, a model for wet and dry age-related macular degeneration. We also examined a new feature of interest in standard OCT image data, the ratio of maximum intensity in the retinal pigment epithelium to that of the choroid (RC ratio). These new biomarkers were supported by polarization-sensitive OCT and histological analysis. Results SSCoV correlated well with depolarization metrics both in phantom and in vivo with both metrics decreasing more rapidly in SOD1−/− mice with age (P < 0.05). This finding is correlated with reduced melanin pigmentation in the choroid over time. The RC ratio clearly differentiated the SOD1−/− and control groups (P < 0.0005) irrespective of time and may indicate lower retinal pigment epithelium melanin in the SOD1−/− mice. Histological analysis showed decreased melanin content and potential differences in melanin granule shape in SOD1−/− mice. Conclusions SSCoV and RC ratio biomarkers provided insights into the changes of retinal melanin in the SOD1−/− model longitudinally and noninvasively. Translational Relevance These biomarkers were designed with the potential for rapid adoption by existing clinical OCT systems without requiring new hardware.
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Affiliation(s)
- Conrad W Merkle
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Austria
| | - Marco Augustin
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Austria
| | - Danielle J Harper
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Austria
| | - Martin Glösmann
- Core Facility for Research and Technology, University of Veterinary Medicine Vienna, Austria
| | - Bernhard Baumann
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Austria
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16
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Venkatesh R, Agrawal S, Reddy NG, Sridharan A, Ong J, Yadav NK, Chhablani J. Choroidal and retinal thickness variations in ocular albinism. Indian J Ophthalmol 2022; 70:2506-2510. [PMID: 35791146 PMCID: PMC9426091 DOI: 10.4103/ijo.ijo_2907_21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Purpose To study the retinal and choroidal thickness variations on enhanced depth imaging optical coherence tomography scans in ocular albinism (OA) and compare with age-matched healthy subjects. Methods This retrospective observational study had 48 eyes of 24 patients diagnosed clinically as OA and age, sex, and axial length-matched control healthy subjects. All patients underwent detailed ophthalmic examination and a single-line horizontal-raster enhanced depth imaging - optical coherence tomography scan (Spectralis, Heidelberg Engineering). Retinal and choroidal thickness was measured, compared, and analyzed between the two groups. Mann-Whitney U test was used for analysis between the two groups. P < 0.05 was considered significant. Results The mean age was 28.3 ± 11.6 and 29.9 ± 10.6 years in the OA group and control group, respectively. Spherical equivalents ranged from -8.5D to +10.5D in the OA group and from -8.0D to +10.0D in the control group. The mean axial length between the two groups (P = 0.652) were comparable. The average retinal thickness (272 ± 34.3 vs. 213 ± 13.8 μm; P < 0.001) was greater in the OA group as compared to controls. The mean choroidal thickness (184 ± 78.4 vs. 287 ± 46.4 μm; P < 0.001) was significantly thinner in the OA group. Conclusion Acquisition of OCT scans in OA can be challenging. This study showed that the subfoveal retinal thickness and choroidal thickness measured across the scans were significantly different in the OA group compared to controls. In the future, more studies are required to evaluate the role of the choroid and its relationship to emmetropization in albinism.
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Affiliation(s)
- Ramesh Venkatesh
- Department of Retina-Vitreous, Narayana Nethralaya, Benguluru, Karnataka, India
| | - Sameeksha Agrawal
- Department of Retina-Vitreous, Narayana Nethralaya, Benguluru, Karnataka, India
| | | | - Akhila Sridharan
- Department of Retina-Vitreous, Narayana Nethralaya, Benguluru, Karnataka, India
| | - Joshua Ong
- Medical Retina and Vitreoretinal Surgery, University of Pittsburgh School of Medicine, Pittsburg, PA, USA
| | - Naresh Kumar Yadav
- Department of Retina-Vitreous, Narayana Nethralaya, Benguluru, Karnataka, India
| | - Jay Chhablani
- Medical Retina and Vitreoretinal Surgery, University of Pittsburgh School of Medicine, Pittsburg, PA, USA
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17
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Kellner S, Weinitz S, Farmand G, Kellner U. Nahinfrarot-Autofluoreszenz: klinische Anwendung und diagnostische Relevanz. AUGENHEILKUNDE UP2DATE 2022. [DOI: 10.1055/a-1810-1314] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
ZusammenfassungDie Nahinfrarot-Autofluoreszenz (NIA) ist ein nicht-invasives Verfahren zur Untersuchung des retinalen Pigmentepithels (RPE) basierend auf der Darstellung des antioxidativen Schutzfaktors
Melanin in den RPE-Zellen. Die NIA verbessert die Früherkennung chorioretinaler Erkrankungen, da bei vielen dieser Erkrankungen mit der NIA Strukturveränderungen des RPE nachweisbar sind,
bevor sich in anderen Untersuchungen Krankheitszeichen erkennen lassen.
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18
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Kellner S, Weinitz S, Farmand G, Kellner U. [Near-infrared Fundus Autofluorescence: Clinical Application and Diagnostic Relevance]. Klin Monbl Augenheilkd 2022; 239:1059-1076. [PMID: 35609811 DOI: 10.1055/a-1857-1387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Near-infrared autofluorescence (NIA) is a non-invasive retinal imaging technique for examination of the retinal pigment epithelium (RPE) based on the autofluorescence of melanin. Melanin has several functions within the RPE cells, in one of them it serves as a protective antioxidative factor within the RPE cells and is involved in the phagocytosis of photoreceptor outer segments. Disorders that affect the photoreceptor-RPE complex result in alterations of RPE cells which are detectable by alterations of NIA. Therefore, NIA allows to detect early alterations in inherited and acquired chorioretinal disorders, frequently prior to ophthalmoscopical visualisation and often prior to alterations in lipofuscin associated fundus autofluorescence (FAF) or optical coherence tomography (OCT). Although NIA and FAF relate to disorders affecting the RPE, findings between both imaging methods differ and the area involved has been demonstrated to be larger in NIA compared to FAF in several disorders (e.g., age-related macular degeneration, retinitis pigmentosa, ABCA4-gene associated Stargardt disease and cone-rod dystrophy, light damage), indicating that NIA detects earlier alterations compared to FAF. In addition, due to the absence of blue-light filtering which limits foveal visualisation in FAF, foveal alterations can be much better detected using NIA. A reduced subfoveal NIA intensity is the earliest sign of autosomal dominant BEST1-associated disease, when FAF and OCT are still normal. In other disorders, a normal subfoveal NIA intensity is associated with good visual acuity. This review summarizes the present knowledge on NIA and demonstrates biomarkers for various chorioretinal disorders.
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19
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Evaluation of choroidal melanin-containing tissue in healthy Japanese subjects by polarization-sensitive optical coherence tomography. Sci Rep 2022; 12:4048. [PMID: 35260673 PMCID: PMC8904585 DOI: 10.1038/s41598-022-07818-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Accepted: 02/24/2022] [Indexed: 11/08/2022] Open
Abstract
In this study, the choroidal melanin content in healthy eyes was evaluated with polarization-sensitive optical coherence tomography (PS-OCT). We evaluated 105 healthy eyes of 105 Japanese subjects. The mean thickness of melanin-containing tissue in the choroid (thickness of MeCh) and the choroidal melanin occupancy rate within a 5-mm circular region from the foveal center were calculated using the degree of polarization uniformity obtained by PS-OCT and compared with the choroidal thickness, patient age, and axial length. To evaluate regional variations, the 5-mm circular region was divided into a center area and an outer ring area, and the outer ring area was further divided into four areas (nasal, temporal, superior, and inferior). The mean thickness of MeCh showed a significant positive correlation with the choroidal thickness. The mean choroidal melanin occupancy rate showed a significant positive correlation with age. The mean choroidal melanin occupancy rate of the center area was significantly larger than that of the outer ring area. The mean thickness of MeCh and choroidal melanin occupancy rate of the nasal area were significantly lower than those of other areas. The distribution of melanin-containing tissue in the choroid varies significantly with age and location.
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20
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Kim YH, Oh J. Comparison of choroidal hyperreflective spots on optical coherence tomography images between both eyes of normal subjects. Quant Imaging Med Surg 2022; 12:920-935. [PMID: 35111594 DOI: 10.21037/qims-21-637] [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: 06/18/2021] [Accepted: 08/04/2021] [Indexed: 11/06/2022]
Abstract
Background Advancement of optical coherence tomography (OCT) technology allows for better in vivo visualization of the choroidal architecture, which comprises vessels and stroma. However, most OCT studies using image binarization methods have focused only on choroidal vessels represented by dark pixels. This study aimed to compare the distribution of choroidal hyperreflective spots on swept-source OCT (SS-OCT) images between both eyes of normal subjects. Methods In this observational comparative study, we included SS-OCT images of healthy subjects, which were prospectively obtained to compare images among the devices. SS-OCT images acquired using PLEX Elite 9000 and DRI-OCT Triton were analyzed. En-face OCT images were obtained at five different depth positions of the inner choroid at the macula. The mean reflectivity of the choroidal slabs, the number, total area, and circularity of hyperreflective spots were quantitatively compared between the devices and between both eyes of the same subjects. Results In 30 eyes of 15 healthy subjects, the mean reflectivity of the choroidal slabs varied with the scan depth on both devices (P<0.001 and P<0.001). Hyperreflective spots were similarly distributed in the images from both devices, but at different depths. The number and area of hyperreflective spots in the second and third layers of the DRI-OCT Triton were positively correlated with those in the fourth and fifth layers of the PLEX Elite 9000, respectively (all P<0.05). The intraclass correlation coefficients (ICC) for the area of hyperreflective spots were excellent for the third slab of the DRI-OCT and the fifth slab of the PLEX Elite (ICC =0.798; 95% CI, -0.576-0.904). The number and area of hyperreflective spots were correlated between both eyes in the third, fourth and fifth layers on DRI-OCT Triton (all P<0.05) and in the first, second, and fifth layers on PLEX Elite 9000 (all P<0.05). Conclusions Hyperreflective spots in en-face images from two different SS-OCT devices were similarly observed between both eyes of the same person. The distributions of spots between the two eyes of the same person were correlated. These findings suggest that the distribution of hyperreflective spots on the choroid reflects the choroidal characteristics of the subject.
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Affiliation(s)
- Young Ho Kim
- Department of Ophthalmology, Korea University College of Medicine, Seoul, Korea
| | - Jaeryung Oh
- Department of Ophthalmology, Korea University College of Medicine, Seoul, Korea
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21
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Venkatesh R, Pereira A, Gupta A. Conventional colour fundus photography over multicolour imaging in identifying peripapillary intrachoroidal cavitation in myopic eyes. BMJ Case Rep 2021; 14:e246837. [PMID: 34728516 PMCID: PMC8565547 DOI: 10.1136/bcr-2021-246837] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/16/2021] [Indexed: 11/04/2022] Open
Affiliation(s)
- Ramesh Venkatesh
- Department of Retina and Vitreous, Narayana Nethralaya, Bangalore, India
| | | | - Aditi Gupta
- Department of Retina and Vitreous, Narayana Nethralaya, Bangalore, India
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22
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Mathis T, Vasseur V, Zuber K, Arej N, Loria O, Kodjikian L, Sennlaub F, Mauget‐Faÿsse M. Light-induced modifications of the outer retinal hyperreflective layers on spectral-domain optical coherence tomography in humans: an experimental study. Acta Ophthalmol 2021; 99:765-772. [PMID: 33393736 PMCID: PMC8596705 DOI: 10.1111/aos.14723] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2019] [Revised: 11/14/2020] [Accepted: 11/23/2020] [Indexed: 11/28/2022]
Abstract
Purpose Numerous small hyperreflective dots (HRDs) can be seen within the hyporeflective layer between the ellipsoid zone (EZ) and the interdigitation zone (IZ) on C‐scan spectral‐domain optical coherence tomography (SD‐OCT) with a yet unknown variation under light conditions. The aim of this study was to explore light‐induced SD‐OCT changes in these HRDs. Methods The study subjects were randomly assigned to two groups: Group 1 experienced a dark adaptation protocol followed by intense retinal photobleaching, while Group 2, serving as the control group, was exposed to constant ambient light without any variation. The number of HRDs was automatically counted. Results Twenty healthy volunteers were prospectively included. The number of HRDs differed significantly over time (p = 0.0013). They decreased in Group 1 after dark adaptation and retinal photobleaching before returning to baseline levels 30 min later; conversely, they remained relatively constant in Group 2 throughout the study (p < 0.001). Light‐skinned subjects had less HRD than dark‐skinned subjects. Conclusion We observed light‐induced modifications in the space between the EZ and the IZ. We hypothesize that the HRDs visible in this zone correspond to melanosomes that are mobilized during the light stimulation protocol. Larger studies are recommended to further evaluate and confirm light‐induced SD‐OCT changes under physiological and pathological conditions.
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Affiliation(s)
- Thibaud Mathis
- Department of Ophthalmology Croix‐Rousse University Hospital Hospices Civils de Lyon University of Medicine Lyon 1 Lyon France
- UMR‐CNRS 5510 Matéis Lyon 1 University Lyon France
- INSERM CNRS Institut de la Vision Sorbonne University Paris France
| | - Vivien Vasseur
- Department of Ophthalmology Rothschild Foundation Paris France
| | - Kevin Zuber
- Department of Ophthalmology Rothschild Foundation Paris France
| | - Nicolas Arej
- Department of Ophthalmology Rothschild Foundation Paris France
| | - Olivier Loria
- Department of Ophthalmology Croix‐Rousse University Hospital Hospices Civils de Lyon University of Medicine Lyon 1 Lyon France
- UMR‐CNRS 5510 Matéis Lyon 1 University Lyon France
| | - Laurent Kodjikian
- Department of Ophthalmology Croix‐Rousse University Hospital Hospices Civils de Lyon University of Medicine Lyon 1 Lyon France
- UMR‐CNRS 5510 Matéis Lyon 1 University Lyon France
| | - Florian Sennlaub
- INSERM CNRS Institut de la Vision Sorbonne University Paris France
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23
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Lem DW, Davey PG, Gierhart DL, Rosen RB. A Systematic Review of Carotenoids in the Management of Age-Related Macular Degeneration. Antioxidants (Basel) 2021; 10:1255. [PMID: 34439503 PMCID: PMC8389280 DOI: 10.3390/antiox10081255] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 07/30/2021] [Accepted: 08/02/2021] [Indexed: 01/14/2023] Open
Abstract
Age-related macular degeneration (AMD) remains a leading cause of modifiable vision loss in older adults. Chronic oxidative injury and compromised antioxidant defenses represent essential drivers in the development of retinal neurodegeneration. Overwhelming free radical species formation results in mitochondrial dysfunction, as well as cellular and metabolic imbalance, which becomes exacerbated with increasing age. Thus, the depletion of systemic antioxidant capacity further proliferates oxidative stress in AMD-affected eyes, resulting in loss of photoreceptors, neuroinflammation, and ultimately atrophy within the retinal tissue. The aim of this systematic review is to examine the neuroprotective potential of the xanthophyll carotenoids lutein, zeaxanthin, and meso-zeaxanthin on retinal neurodegeneration for the purpose of adjunctive nutraceutical strategy in the management of AMD. A comprehensive literature review was performed to retrieve 55 eligible publications, using four database searches from PubMed, Embase, Cochrane Library, and the Web of Science. Epidemiology studies indicated an enhanced risk reduction against late AMD with greater dietary consumption of carotenoids, meanwhile greater concentrations in macular pigment demonstrated significant improvements in visual function among AMD patients. Collectively, evidence strongly suggests that carotenoid vitamin therapies offer remarkable synergic protection in the neurosensory retina, with the potential to serve as adjunctive nutraceutical therapy in the management of established AMD, albeit these benefits may vary among different stages of disease.
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Affiliation(s)
- Drake W. Lem
- College of Optometry, Western University of Health Sciences, Pomona, CA 91766, USA;
| | | | | | - Richard B. Rosen
- Department of Ophthalmology, New York Eye and Ear Infirmary of Mount Sinai, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA;
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24
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Zhou S, Zeng H, Huang J, Lei L, Tong X, Li S, Zhou Y, Guo H, Khan M, Luo L, Xiao R, Chen J, Zeng Q. Epigenetic regulation of melanogenesis. Ageing Res Rev 2021; 69:101349. [PMID: 33984527 DOI: 10.1016/j.arr.2021.101349] [Citation(s) in RCA: 48] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2020] [Revised: 04/19/2021] [Accepted: 04/26/2021] [Indexed: 02/07/2023]
Abstract
Melanogenesis is a complex process in which melanin is synthesized in melanocytes and transported to keratinocytes, which involves multiple genes and signaling pathways. Epigenetics refers to the potential genetic changes that affect gene expression without involving changes in the original sequence of DNA nucleotides. DNA methylation regulates the expression of key genes such as tyrosinase (TYR), tyrosinase-related protein 1 (TYRP1), dopachrome tautomerase (DCT) and microphthalmia-associated transcription factor (MITF), as well as paracrine factors such as stem cell factor (SCF) and endothelin-1 (ET-1) in melanogenesis. Potential DNA methylation sites are present in the genes of melanogenesis-related signaling pathways such as "Wnt", "PI3K/Akt/CREB" and "MAPK". H3K27 acetylation is abundant in melanogenesis-related genes. Both the upstream activation and downstream regulation of MITF depend on histone acetyltransferase CBP/p300, and pH-induced H3K27 acetylation may be the amplifying mechanism of MITF's effect. HDAC1 and HDAC10 catalyze histone deacetylation of melanogenesis-related gene promoters. Chromatin remodelers SWI/SNF complex and ISWI complex use the energy of ATP hydrolysis to rearrange nucleosomes, while their active subunits BRG1, BRM and BPTF, act as activators and cofactors of MITF. MicroRNAs (miRNAs) can directly target a large number of melanogenesis-related genes, while long noncoding RNAs (lncRNAs) and circular RNAs (circRNAs) regulate melanogenesis in a variety of ways. Interactions exist among the epigenetic mechanisms of melanogenesis. For example, the methyl CpG binding domain protein 2 (MeCP2) links DNA methylation, histone deacetylation, and histone methylation. Epigenetic-based therapy provides novel opportunities for treating dermatoses that are caused by pigmentation disturbances. This review summarizes the epigenetic regulation mechanisms of melanogenesis, and examines the pathogenesis and treatment of epigenetics in pigmentation disorders.
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Lem DW, Gierhart DL, Davey PG. A Systematic Review of Carotenoids in the Management of Diabetic Retinopathy. Nutrients 2021; 13:2441. [PMID: 34371951 PMCID: PMC8308772 DOI: 10.3390/nu13072441] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2021] [Revised: 07/08/2021] [Accepted: 07/12/2021] [Indexed: 12/21/2022] Open
Abstract
Diabetic retinopathy, which was primarily regarded as a microvascular disease, is the leading cause of irreversible blindness worldwide. With obesity at epidemic proportions, diabetes-related ocular problems are exponentially increasing in the developed world. Oxidative stress due to hyperglycemic states and its associated inflammation is one of the pathological mechanisms which leads to depletion of endogenous antioxidants in retina in a diabetic patient. This contributes to a cascade of events that finally leads to retinal neurodegeneration and irreversible vision loss. The xanthophylls lutein and zeaxanthin are known to promote retinal health, improve visual function in retinal diseases such as age-related macular degeneration that has oxidative damage central in its etiopathogenesis. Thus, it can be hypothesized that dietary supplements with xanthophylls that are potent antioxidants may regenerate the compromised antioxidant capacity as a consequence of the diabetic state, therefore ultimately promoting retinal health and visual improvement. We performed a comprehensive literature review of the National Library of Medicine and Web of Science databases, resulting in 341 publications meeting search criteria, of which, 18 were found eligible for inclusion in this review. Lutein and zeaxanthin demonstrated significant protection against capillary cell degeneration and hyperglycemia-induced changes in retinal vasculature. Observational studies indicate that depletion of xanthophyll carotenoids in the macula may represent a novel feature of DR, specifically in patients with type 2 or poorly managed type 1 diabetes. Meanwhile, early interventional trials with dietary carotenoid supplementation show promise in improving their levels in serum and macular pigments concomitant with benefits in visual performance. These findings provide a strong molecular basis and a line of evidence that suggests carotenoid vitamin therapy may offer enhanced neuroprotective effects with therapeutic potential to function as an adjunct nutraceutical strategy for management of diabetic retinopathy.
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Affiliation(s)
- Drake W. Lem
- College of Optometry, Western University of Health Sciences, 309 E Second St, Pomona, CA 91766, USA;
| | | | - Pinakin Gunvant Davey
- College of Optometry, Western University of Health Sciences, 309 E Second St, Pomona, CA 91766, USA;
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Lem DW, Gierhart DL, Davey PG. Carotenoids in the Management of Glaucoma: A Systematic Review of the Evidence. Nutrients 2021; 13:nu13061949. [PMID: 34204051 PMCID: PMC8228567 DOI: 10.3390/nu13061949] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Revised: 06/01/2021] [Accepted: 06/04/2021] [Indexed: 12/23/2022] Open
Abstract
Primary open-angle glaucoma (POAG) remains a leading cause of irreversible blindness globally. Recent evidence further substantiates sustained oxidative stress, and compromised antioxidant defenses are key drivers in the onset of glaucomatous neurodegeneration. Overwhelming oxidative injury is likely attributed to compounding mitochondrial dysfunction that worsens with age-related processes, causing aberrant formation of free radical species. Thus, a compromised systemic antioxidant capacity exacerbates further oxidative insult in glaucoma, leading to apoptosis, neuroinflammation, and subsequent tissue injury. The purpose of this systematic review is to investigate the neuroprotective benefits of the macular carotenoids lutein, zeaxanthin, and meso-zeaxanthin on glaucomatous neurodegeneration for the purpose of adjunctive nutraceutical treatment in glaucoma. A comprehensive literature search was conducted in three databases (PubMed, Cochrane Library, and Web of Science) and 20 records were identified for screening. Lutein demonstrated enhanced neuroprotection on retinal ganglion cell survival and preserved synaptic activity. In clinical studies, a protective trend was seen with greater dietary consumption of carotenoids and risk of glaucoma, while greater carotenoid levels in macular pigment were largely associated with improved visual performance in glaucomatous eyes. The data suggest that carotenoid vitamin therapy exerts synergic neuroprotective benefits and has the capacity to serve adjunctive therapy in the management of glaucoma.
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Affiliation(s)
- Drake W. Lem
- College of Optometry, Western University of Health Sciences, 309 E Second St, Pomona, CA 91766, USA;
| | | | - Pinakin Gunvant Davey
- College of Optometry, Western University of Health Sciences, 309 E Second St, Pomona, CA 91766, USA;
- Correspondence: ; Tel.: +1-909-469-8473
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Siddiqui MF, Jeon S, Kim MM. Rapid and sensitive detection of melanin using glutathione conjugated gold nanocluster based fluorescence quenching assay. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2021; 247:119086. [PMID: 33128947 DOI: 10.1016/j.saa.2020.119086] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 09/14/2020] [Accepted: 10/10/2020] [Indexed: 06/11/2023]
Abstract
In the present study, a rapid, facile, and highly sensitive assay based on glutathione conjugated gold nanocluster (GSH-AuNCs) is developed for the detection of melanin. The analysis of melanin which is linked to several diseases is crucial. The current methods for melanin estimation are complex and long, thus demands an alternative technology. In general, melanin exhibits photoactive properties, thus, it might have fluorescence quenching properties through the phenomenon of fluorescence resonance energy transfer. To verify our assumption, we have developed the fluorescence quenching assay based on gold nanocluster and melanin interaction. As a result, under the optimized condition, the developed quenching assay demonstrated the high selectivity and sensitivity toward melanin with a limit of detection and correlation coefficient of 0.060 μg/mL and 0.993, respectively. Moreover, the whole process represented the rapid assay time of 30 min to complete. To validate the performance of our assay on real samples, B16F1 cells lysate, and hair samples were tested that provided satisfactory results. Therefore, we believe that our assay due to good sensitivity and short assay time could be beneficial for the clinical diagnosis of melanin in the future study.
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Affiliation(s)
- Mohd Farhan Siddiqui
- Department of Applied Chemistry, Dong-Eui University, Busan 614-714, Republic of Korea
| | - Sojeong Jeon
- Department of Biology & Chemistry, Dong-Eui University, Busan 614-714, Republic of Korea
| | - Moon-Moo Kim
- Department of Applied Chemistry, Dong-Eui University, Busan 614-714, Republic of Korea.
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28
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Miura M, Makita S, Yasuno Y, Iwasaki T, Azuma S, Mino T, Yamaguchi T. Evaluation of retinal pigment epithelium changes in serous pigment epithelial detachment in age-related macular degeneration. Sci Rep 2021; 11:2764. [PMID: 33531591 PMCID: PMC7854605 DOI: 10.1038/s41598-021-82563-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Accepted: 01/21/2021] [Indexed: 11/28/2022] Open
Abstract
The purpose of this study was to quantitatively evaluate retinal pigment epithelium (RPE) changes in serous pigment epithelial detachment (PED) among patients with age-related macular degeneration by means of prototype multi-contrast optical coherence tomography (OCT), which is capable of simultaneous collection of OCT angiography, polarization-sensitive OCT, and standard OCT images. We evaluated 26 eyes of 21 patients with serous PED. RPE-melanin OCT images were calculated from the multi-contrast OCT dataset and compared with near-infrared autofluorescence images. An active RPE lesion was defined as an area of thickened RPE-melanin (≥ 70 μm; RPE70) on RPE-melanin OCT. Each PED area was divided into peak and slope regions. RPE70 area ratios were compared with the maximum PED height, PED area, PED volume, and slope area ratio (area of slope region/area of whole PED). RPE-melanin OCT images were consistent with near-infrared autofluorescence images. The RPE70 area ratio in the slope region was significantly negatively correlated with the slope area ratio. Development of active RPE lesions in the slope region was correlated with the PED configuration. Multi-contrast OCT is useful for objective evaluation of changes in the RPE in patients with age-related macular degeneration.
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Affiliation(s)
- Masahiro Miura
- Department of Ophthalmology, Tokyo Medical University, Ibaraki Medical Center, 3-20-1 Chuo, Ami, Inashiki, Ibaraki, 300395, Japan.
| | - Shuichi Makita
- Computational Optics Group, University of Tsukuba, Tsukuba, Japan
| | - Yoshiaki Yasuno
- Computational Optics Group, University of Tsukuba, Tsukuba, Japan
| | - Takuya Iwasaki
- Department of Ophthalmology, Tokyo Medical University, Ibaraki Medical Center, 3-20-1 Chuo, Ami, Inashiki, Ibaraki, 300395, Japan
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Galeb HA, Wilkinson EL, Stowell AF, Lin H, Murphy ST, Martin‐Hirsch PL, Mort RL, Taylor AM, Hardy JG. Melanins as Sustainable Resources for Advanced Biotechnological Applications. GLOBAL CHALLENGES (HOBOKEN, NJ) 2021; 5:2000102. [PMID: 33552556 PMCID: PMC7857133 DOI: 10.1002/gch2.202000102] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Revised: 11/04/2020] [Indexed: 05/17/2023]
Abstract
Melanins are a class of biopolymers that are widespread in nature and have diverse origins, chemical compositions, and functions. Their chemical, electrical, optical, and paramagnetic properties offer opportunities for applications in materials science, particularly for medical and technical uses. This review focuses on the application of analytical techniques to study melanins in multidisciplinary contexts with a view to their use as sustainable resources for advanced biotechnological applications, and how these may facilitate the achievement of the United Nations Sustainable Development Goals.
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Affiliation(s)
- Hanaa A. Galeb
- Department of ChemistryLancaster UniversityLancasterLA1 4YBUK
- Department of ChemistryScience and Arts CollegeRabigh CampusKing Abdulaziz UniversityJeddah21577Saudi Arabia
| | - Emma L. Wilkinson
- Department of Biomedical and Life SciencesLancaster UniversityLancasterLA1 4YGUK
| | - Alison F. Stowell
- Department of Organisation, Work and TechnologyLancaster University Management SchoolLancaster UniversityLancasterLA1 4YXUK
| | - Hungyen Lin
- Department of EngineeringLancaster UniversityLancasterLA1 4YWUK
| | - Samuel T. Murphy
- Department of EngineeringLancaster UniversityLancasterLA1 4YWUK
- Materials Science InstituteLancaster UniversityLancasterLA1 4YBUK
| | - Pierre L. Martin‐Hirsch
- Lancashire Teaching Hospitals NHS TrustRoyal Preston HospitalSharoe Green LanePrestonPR2 9HTUK
| | - Richard L. Mort
- Department of Biomedical and Life SciencesLancaster UniversityLancasterLA1 4YGUK
| | - Adam M. Taylor
- Lancaster Medical SchoolLancaster UniversityLancasterLA1 4YWUK
| | - John G. Hardy
- Department of ChemistryLancaster UniversityLancasterLA1 4YBUK
- Materials Science InstituteLancaster UniversityLancasterLA1 4YBUK
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The Neuromelanin Paradox and Its Dual Role in Oxidative Stress and Neurodegeneration. Antioxidants (Basel) 2021; 10:antiox10010124. [PMID: 33467040 PMCID: PMC7829956 DOI: 10.3390/antiox10010124] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 01/12/2021] [Accepted: 01/13/2021] [Indexed: 12/12/2022] Open
Abstract
Aging is associated with an increasing dysfunction of key brain homeostasis mechanisms and represents the main risk factor across most neurodegenerative disorders. However, the degree of dysregulation and the affectation of specific pathways set apart normal aging from neurodegenerative disorders. In particular, the neuronal metabolism of catecholaminergic neurotransmitters appears to be a specifically sensitive pathway that is affected in different neurodegenerations. In humans, catecholaminergic neurons are characterized by an age-related accumulation of neuromelanin (NM), rendering the soma of the neurons black. This intracellular NM appears to serve as a very efficient quencher for toxic molecules. However, when a neuron degenerates, NM is released together with its load (many undegraded cellular components, transition metals, lipids, xenobiotics) contributing to initiate and worsen an eventual immune response, exacerbating the oxidative stress, ultimately leading to the neurodegenerative process. This review focuses on the analysis of the role of NM in normal aging and neurodegeneration related to its capabilities as an antioxidant and scavenging of harmful molecules, versus its involvement in oxidative stress and aberrant immune response, depending on NM saturation state and its extracellular release.
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Hsu D, Kwon JH, Ng R, Makita S, Yasuno Y, Sarunic MV, Ju MJ. Quantitative multi-contrast in vivo mouse imaging with polarization diversity optical coherence tomography and angiography. BIOMEDICAL OPTICS EXPRESS 2020; 11:6945-6961. [PMID: 33408972 PMCID: PMC7747897 DOI: 10.1364/boe.403209] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 10/15/2020] [Accepted: 10/31/2020] [Indexed: 05/02/2023]
Abstract
Retinal microvasculature and the retinal pigment epithelium (RPE) play vital roles in maintaining the health and metabolic activity of the eye. Visualization of these retina structures is essential for pre-clinical studies of vision-robbing diseases, such as age-related macular degeneration (AMD). We have developed a quantitative multi-contrast polarization diversity OCT and angiography (QMC-PD-OCTA) system for imaging and visualizing pigment in the RPE using degree of polarization uniformity (DOPU), along with flow in the retinal capillaries using OCT angiography (OCTA). An adaptive DOPU averaging kernel was developed to increase quantifiable values from visual data, and QMC en face images permit simultaneous visualization of vessel location, depth, melanin region thickness, and mean DOPU values, allowing rapid identification and differentiation of disease symptoms. The retina of five different mice strains were measured in vivo, with results demonstrating potential for pre-clinical studies of retinal disorders.
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Affiliation(s)
- Destiny Hsu
- Simon Fraser University, Biomedical Optics Research Group, Department of Engineering Science, Burnaby, British Columbia, Canada
- co-first author
| | - Ji Hoon Kwon
- Simon Fraser University, Biomedical Optics Research Group, Department of Engineering Science, Burnaby, British Columbia, Canada
- co-first author
| | - Ringo Ng
- Simon Fraser University, Biomedical Optics Research Group, Department of Engineering Science, Burnaby, British Columbia, Canada
| | - Shuichi Makita
- University of Tsukuba, Computational Optics Group, Institute of Applied Physics, Japan
| | - Yoshiaki Yasuno
- University of Tsukuba, Computational Optics Group, Institute of Applied Physics, Japan
| | - Marinko V. Sarunic
- Simon Fraser University, Biomedical Optics Research Group, Department of Engineering Science, Burnaby, British Columbia, Canada
| | - Myeong Jin Ju
- Simon Fraser University, Biomedical Optics Research Group, Department of Engineering Science, Burnaby, British Columbia, Canada
- University of British Columbia, Department of Ophthalmology and Visual Sciences, Vancouver, British Columbia, Canada
- University of British Columbia, School of Biomedical Engineering, Vancouver, British Columbia, Canada
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Yamanari M, Mase M, Obata R, Matsuzaki M, Minami T, Takagi S, Yamamoto M, Miyamoto N, Ueda K, Koide N, Maeda T, Totani K, Aoki N, Hirami Y, Sugiyama S, Mandai M, Aihara M, Takahashi M, Kato S, Kurimoto Y. Melanin concentration and depolarization metrics measurement by polarization-sensitive optical coherence tomography. Sci Rep 2020; 10:19513. [PMID: 33177585 PMCID: PMC7658243 DOI: 10.1038/s41598-020-76397-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Accepted: 10/23/2020] [Indexed: 11/16/2022] Open
Abstract
Imaging of melanin in the eye is important as the melanin is structurally associated with some ocular diseases, such as age-related macular degeneration. Although optical coherence tomography (OCT) cannot distinguish tissues containing the melanin from other tissues intrinsically, polarization-sensitive OCT (PS-OCT) can detect the melanin through spatial depolarization of the backscattered light from the melanin granules. Entropy is one of the depolarization metrics that can be used to detect malanin granules in PS-OCT and valuable quantitative information on ocular tissue abnormalities can be retrived by correlating entropy with the melanin concentration. In this study, we investigate a relationship between the melanin concentration and some depolarization metrics including the entropy, and show that the entropy is linearly proportional to the melanin concentration in double logarithmic scale when noise bias is corrected for the entropy. In addition, we also confirm that the entropy does not depend on the incident state of polarization using the experimental data, which is one of important attributes that depolarization metrics should have. The dependence on the incident state of polarization is also analyzed for other depolarization metrics.
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Affiliation(s)
| | - Mutsuki Mase
- Engineering Department, Tomey Corporation, Nagoya, Aichi, Japan
| | - Ryo Obata
- Department of Ophthalmology, Graduate School of Medicine and Faculty of Medicine, The University of Tokyo, Tokyo, Japan
| | - Mitsuhiro Matsuzaki
- Department of Ophthalmology, Kobe City Eye Hospital, Kobe, Hyogo, Japan.,Department of Ophthalmology, Kobe City Medical Centre General Hospital, Kobe, Hyogo, Japan
| | - Takahiro Minami
- Department of Ophthalmology, Graduate School of Medicine and Faculty of Medicine, The University of Tokyo, Tokyo, Japan
| | - Seiji Takagi
- Department of Ophthalmology, Kobe City Eye Hospital, Kobe, Hyogo, Japan.,Department of Ophthalmology, Kobe City Medical Centre General Hospital, Kobe, Hyogo, Japan
| | - Motoshi Yamamoto
- Department of Ophthalmology, Graduate School of Medicine and Faculty of Medicine, The University of Tokyo, Tokyo, Japan
| | - Noriko Miyamoto
- Department of Ophthalmology, Kobe City Eye Hospital, Kobe, Hyogo, Japan.,Department of Ophthalmology, Kobe City Medical Centre General Hospital, Kobe, Hyogo, Japan
| | - Koji Ueda
- Department of Ophthalmology, Graduate School of Medicine and Faculty of Medicine, The University of Tokyo, Tokyo, Japan
| | - Naoshi Koide
- Laboratory for Retinal Regeneration, Riken Centre for Biosystems Dynamics Research, Kobe, Hyogo, Japan
| | - Tadao Maeda
- Department of Ophthalmology, Kobe City Eye Hospital, Kobe, Hyogo, Japan.,Department of Ophthalmology, Kobe City Medical Centre General Hospital, Kobe, Hyogo, Japan.,Laboratory for Retinal Regeneration, Riken Centre for Biosystems Dynamics Research, Kobe, Hyogo, Japan
| | - Kota Totani
- Engineering Department, Tomey Corporation, Nagoya, Aichi, Japan
| | - Nobuyori Aoki
- Engineering Department, Tomey Corporation, Nagoya, Aichi, Japan
| | - Yasuhiko Hirami
- Department of Ophthalmology, Kobe City Eye Hospital, Kobe, Hyogo, Japan.,Department of Ophthalmology, Kobe City Medical Centre General Hospital, Kobe, Hyogo, Japan.,Laboratory for Retinal Regeneration, Riken Centre for Biosystems Dynamics Research, Kobe, Hyogo, Japan
| | | | - Michiko Mandai
- Department of Ophthalmology, Kobe City Eye Hospital, Kobe, Hyogo, Japan.,Laboratory for Retinal Regeneration, Riken Centre for Biosystems Dynamics Research, Kobe, Hyogo, Japan
| | - Makoto Aihara
- Department of Ophthalmology, Graduate School of Medicine and Faculty of Medicine, The University of Tokyo, Tokyo, Japan
| | - Masayo Takahashi
- Department of Ophthalmology, Kobe City Eye Hospital, Kobe, Hyogo, Japan.,Laboratory for Retinal Regeneration, Riken Centre for Biosystems Dynamics Research, Kobe, Hyogo, Japan.,Vision Care Inc., Kobe, Hyogo, Japan
| | - Satoshi Kato
- Department of Ophthalmology, Graduate School of Medicine and Faculty of Medicine, The University of Tokyo, Tokyo, Japan
| | - Yasuo Kurimoto
- Department of Ophthalmology, Kobe City Eye Hospital, Kobe, Hyogo, Japan.,Department of Ophthalmology, Kobe City Medical Centre General Hospital, Kobe, Hyogo, Japan.,Laboratory for Retinal Regeneration, Riken Centre for Biosystems Dynamics Research, Kobe, Hyogo, Japan
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Bermond K, Wobbe C, Tarau IS, Heintzmann R, Hillenkamp J, Curcio CA, Sloan KR, Ach T. Autofluorescent Granules of the Human Retinal Pigment Epithelium: Phenotypes, Intracellular Distribution, and Age-Related Topography. Invest Ophthalmol Vis Sci 2020; 61:35. [PMID: 32433758 PMCID: PMC7405767 DOI: 10.1167/iovs.61.5.35] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose The human retinal pigment epithelium (RPE) accumulates granules significant for autofluorescence imaging. Knowledge of intracellular accumulation and distribution is limited. Using high-resolution microscopy techniques, we determined the total number of granules per cell, intracellular distribution, and changes related to retinal topography and age. Methods RPE cells from the fovea, perifovea, and near-periphery of 15 human RPE flat mounts were imaged using structured illumination microscopy (SIM) and confocal fluorescence microscopy in young (≤51 years, n = 8) and older (>80 years, n = 7) donors. Using custom FIJI plugins, granules were marked with computer assistance, classified based on morphological and autofluorescence properties, and analyzed with regard to intracellular distribution, total number per cell, and granule density. Results A total of 193,096 granules in 450 RPE cell bodies were analyzed. Based on autofluorescence properties, size, and composition, the RPE granules exhibited nine different phenotypes (lipofuscin, two; melanolipofuscin, five; melanosomes, two), distinguishable by SIM. Overall, lipofuscin (low at the fovea but increases with eccentricity and age) and melanolipofuscin (equally distributed at all three locations with no age-related changes) were the major granule types. Melanosomes were under-represented due to suboptimal visualization of apical processes in flat mounts. Conclusions Low lipofuscin and high melanolipofuscin content within foveal RPE cell bodies and abundant lipofuscin at the perifovea suggest a different genesis, plausibly related to the population of overlying photoreceptors (fovea, cones only; perifovea, highest rod density). This systematic analysis provides further insight into RPE cell and granule physiology and links granule load to cell autofluorescence, providing a subcellular basis for the interpretation of clinical fundus autofluorescence.
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Öncül H, Ayhan E. Retinal nerve fiber layer, retinal pigment epithelium, and choroidal thickness in vitiligo patients. J Cosmet Dermatol 2020; 19:3032-3037. [PMID: 32515874 DOI: 10.1111/jocd.13367] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 02/23/2020] [Accepted: 02/25/2020] [Indexed: 11/28/2022]
Abstract
BACKGROUND Vitiligo is one of the common pigmentary disorders affecting the ocular structures. AIM To determine the retinal nerve fiber layer (RNFL), retinal pigment epithelium (RPE), and choroidal thickness (CT) in vitiligo patients and to evaluate the relationship between choroidal thickness and vitiligo subtypes. METHODS The right eyes of 106 participants (51 vitiligo, 55 nonvitiligo) were included in the study. All of the participants underwent detailed eye examinations and spectral-domain optical coherence tomography (SD-OCT) examinations. CT was measured manually with enhanced depth imaging optical coherence tomography (Edi-OCT) (subfoveal [SubF], nasal n500 µm [N1], n1500 µm [N2]), and temporal (t500 µm [T1], t1500 µm [T2]). RESULTS In vitiligo patients, CT values were significantly lower in the SubF, N1, N2, T1, and T2 areas compared to the control group (P = .001, P = .011, P = .002, P = .005, P ˂ .001, respectively). Periorbital involvement did not affect CT (P = .355, P = .746, P = .443, P = .633, P = .558, respectively). However, in patients with periorbital region involvement, the CT was significantly reduced if the lesion had a universal character (P ˂ .001, P = .001, P = .011, P ˂ .001, P = .002, respectively). It was observed that RPE thickness decreased in vitiligo, but this difference was not statistically significant (P = .140). RNFL thickness was unaffected in all quadrants. A positive correlation (r = .286, r = .280, respectively) was observed between the Vitiligo Area Severity Index (VASI) and age and disease duration. A negative correlation (r = -.360, r = -.316, r = -.315, r = -.313, respectively) was found in the CT of the SubF, N1, N2, T1, and T2 areas. CONCLUSION Vitiligo patients should be closely monitored for possible posterior ocular segment disorders.
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Affiliation(s)
- Hasan Öncül
- Department of Ophthalmology, University of Health Sciences Gazi Yaşargil Education Research Hospital, Diyarbakir, Turkey
| | - Erhan Ayhan
- Department of Dermatology, University of Health Sciences Gazi Yaşargil Education Research Hospital, Diyarbakir, Turkey
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35
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Normand G, Maker M, Penraat J, Kovach K, Ghosh JG, Grosskreutz C, Chandra S. Non-invasive molecular tracking method that measures ocular drug distribution in non-human primates. Commun Biol 2020; 3:16. [PMID: 31925329 PMCID: PMC6949284 DOI: 10.1038/s42003-019-0731-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Accepted: 12/07/2019] [Indexed: 02/02/2023] Open
Abstract
Intravitreal (IVT) injection has become the standard route for drug administration in retinal diseases. However, the ability to measure biodistribution of ocular therapeutics in large species remains limited, due to the invasive nature of some techniques or their lack of spatial information. The aim of this study was to develop in cynomolgus monkeys a non-invasive fluorescence imaging technology that enables tracking of IVT-dosed drugs and could be easily translated into humans. Here, we show a proof-of-concept for labeled ranibizumab with observed half-lives of 3.34 and 4.52 days at the retina and in the vitreous, respectively. We further investigate a long acting anti-VEGF antibody, which remains as an agglomerate with some material leaking out until the end of the study at Day 35. Overall, we were able to visualize and measure differences in the in vivo behavior between short and long-acting antibodies, demonstrating the power of the technology for ocular pharmacokinetics. Guillaume Normand et al. present a non-invasive fluorescence imaging technology that enables a longitudinal tracking of drugs delivered into the eyes. This method allows direct monitoring of any drugs delivered into the eyes, which could potentially inform clinicians of optimal dosing frequency for each patient.
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Affiliation(s)
- Guillaume Normand
- Department of Translational Medicine, Novartis Institutes for BioMedical Research, East Hanover, NJ, 07936, USA.
| | - Michael Maker
- Department of Translational Medicine, Novartis Institutes for BioMedical Research, East Hanover, NJ, 07936, USA.,InviCRO, 27 Drydock Avenue, Boston, MA, 02210, USA
| | - Jan Penraat
- Lab Animal Services, Novartis Institutes for BioMedical Research, East Hanover, NJ, 07936, USA.,PetSmart, 33963 Doheny Park Road - San Juan, Capistrano, CA, 92675, USA
| | - Kellyann Kovach
- Lab Animal Services, Novartis Institutes for BioMedical Research, East Hanover, NJ, 07936, USA.,Pfizer Corporation, Comparative Medicine, Middletown Road, Pearl River, NY, USA
| | - Joy G Ghosh
- Ophthalmology Research, Novartis Institutes for BioMedical Research, Cambridge, MA, 02139, USA.,Bain Capital Life Sciences, 200 Clarendon Street, Boston, MA, 02116, USA
| | - Cynthia Grosskreutz
- Department of Translational Medicine, Novartis Institutes for BioMedical Research, East Hanover, NJ, 07936, USA.,Ophthalmology Research, Novartis Institutes for Biomedical Research, Cambrodge, MA, 02139, USA
| | - Sudeep Chandra
- Department of Translational Medicine, Novartis Institutes for BioMedical Research, East Hanover, NJ, 07936, USA
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36
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Harper DJ, Konegger T, Augustin M, Schützenberger K, Eugui P, Lichtenegger A, Merkle CW, Hitzenberger CK, Glösmann M, Baumann B. Hyperspectral optical coherence tomography for in vivo visualization of melanin in the retinal pigment epithelium. JOURNAL OF BIOPHOTONICS 2019; 12:e201900153. [PMID: 31334610 PMCID: PMC7065636 DOI: 10.1002/jbio.201900153] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2019] [Revised: 06/19/2019] [Accepted: 07/18/2019] [Indexed: 05/09/2023]
Abstract
Previous studies for melanin visualization in the retinal pigment epithelium (RPE) have exploited either its absorption properties (using photoacoustic tomography or photothermal optical coherence tomography [OCT]) or its depolarization properties (using polarization sensitive OCT). However, these methods are only suitable when the melanin concentration is sufficiently high. In this work, we present the concept of hyperspectral OCT for melanin visualization in the RPE when the concentration is low. Based on white light OCT, a hyperspectral stack of 27 wavelengths (440-700 nm) was created in post-processing for each depth-resolved image. Owing to the size and shape of the melanin granules in the RPE, the variations in backscattering coefficient as a function of wavelength could be identified-a result which is to be expected from Mie theory. This effect was successfully identified both in eumelanin-containing phantoms and in vivo in the low-concentration Brown Norway rat RPE.
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Affiliation(s)
- Danielle J. Harper
- Center for Medical Physics and Biomedical EngineeringMedical University of ViennaViennaAustria
| | - Thomas Konegger
- Institute of Chemical Technologies and Analytics, TU WienViennaAustria
| | - Marco Augustin
- Center for Medical Physics and Biomedical EngineeringMedical University of ViennaViennaAustria
| | - Kornelia Schützenberger
- Center for Medical Physics and Biomedical EngineeringMedical University of ViennaViennaAustria
| | - Pablo Eugui
- Center for Medical Physics and Biomedical EngineeringMedical University of ViennaViennaAustria
| | - Antonia Lichtenegger
- Center for Medical Physics and Biomedical EngineeringMedical University of ViennaViennaAustria
| | - Conrad W. Merkle
- Center for Medical Physics and Biomedical EngineeringMedical University of ViennaViennaAustria
| | | | - Martin Glösmann
- Core Facility for Research and TechnologyUniversity of Veterinary MedicineViennaAustria
| | - Bernhard Baumann
- Center for Medical Physics and Biomedical EngineeringMedical University of ViennaViennaAustria
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37
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Hellinen L, Hagström M, Knuutila H, Ruponen M, Urtti A, Reinisalo M. Characterization of artificially re-pigmented ARPE-19 retinal pigment epithelial cell model. Sci Rep 2019; 9:13761. [PMID: 31551473 PMCID: PMC6760193 DOI: 10.1038/s41598-019-50324-8] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Accepted: 09/10/2019] [Indexed: 12/17/2022] Open
Abstract
Melanin pigment has a significant role in ocular pharmacokinetics, because many drugs bind at high extent to melanin in the retinal pigment epithelial cells. Most retinal pigment epithelial cell lines lack pigmentation and, therefore, we re-pigmented human ARPE-19 cells to generate a pigmented cell model. Melanosomes from porcine retinal pigment epithelium were isolated and co-incubated with ARPE-19 cells that spontaneously phagocytosed the melanosomes. Internalized melanosomes were functionally integrated to the cellular system as evidenced by correct translocation of cellular Rab27a protein to the melanosomal membranes. The pigmentation was retained during cell cultivation and the level of pigmentation can be controlled by altering the amount of administered melanosomes. We used these cells to study melanosomal uptake of six drugs. The uptake was negligible with low melanin-binders (methotrexate, diclofenac) whereas most of the high melanin-binders (propranolol, chloroquine) were extensively taken up by the melanosomes. This cell line can be used to model pigmentation of the retinal pigment epithelium, while maintaining the beneficial cell line characteristics, such as fast generation of cultures, low cost, long-term maintenance and good reproducibility. The model enables studies at normal and decreased levels of pigmentation to model different retinal conditions.
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Affiliation(s)
- Laura Hellinen
- School of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, 70210, Kuopio, Finland
| | - Marja Hagström
- Drug Research Programme, Division of Pharmaceutical Biosciences, Faculty of Pharmacy, University of Helsinki, P.O. Box 56, FI-00014, Helsinki, Finland
| | - Heidi Knuutila
- School of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, 70210, Kuopio, Finland
| | - Marika Ruponen
- School of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, 70210, Kuopio, Finland
| | - Arto Urtti
- School of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, 70210, Kuopio, Finland.,Drug Research Programme, Division of Pharmaceutical Biosciences, Faculty of Pharmacy, University of Helsinki, P.O. Box 56, FI-00014, Helsinki, Finland.,Laboratory of Biohybrid Technologies, Institute of Chemistry, St. Petersburg State University, Peterhoff, 198504 St, Petersburg, Russian Federation, Russia
| | - Mika Reinisalo
- School of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, 70210, Kuopio, Finland. .,Institute of Clinical Medicine, Department of Ophthalmology, Faculty of Health Sciences, University of Eastern Finland, 70210, Kuopio, Finland.
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38
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Mucciolo DP, Murro V, Giorgio D, Sodi A, Passerini I, Virgili G, Rizzo S. Near-infrared autofluorescence in young choroideremia patients. Ophthalmic Genet 2019; 40:421-427. [PMID: 31544579 DOI: 10.1080/13816810.2019.1666881] [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: 10/25/2022]
Abstract
Purpose: To study near-infrared autofluorescence (NIR-AF) and short- wave autofluorescence (SW-AF) imaging modalities in young patients affected with choroideremia (CHM).Methods: NIR-AF and SW-AF images, Optical coherence tomography (OCT) and color fundus images were acquired from 3 young CHM patients (6 eyes) enrolled at the Regional Reference Center for Hereditary Retinal Degenerations of the Eye Clinic in Florence.Results: We studied 3 young CHM patients (6 eyes). The mean age of the patients was 17,3 years. Using NIR-AF, patient P1 was characterized by speckled hypo-autofluorescent areas at the posterior pole with a preserved central hyper-autofluorescence while patient P2 and P3 were characterized by a preserved NIR-AF signal only at the fovea. Using SW-AF, patient P1 was characterized by a normal macular autofluorescence and by a speckled FAF pattern involved the vascular arcades while patient P2 and P3 showed well-demarcated hypo-autofluorescence areas involving the posterior pole with a preserved macular autofluorescence. The differences between NIR-AF and SW-AF were more pronounced in advanced stages. In correspondence of preserved NIR-AF, the OCT examination showed regular and continuous outer retinal hyperreflective bands. We observed abnormal RPE/Bruch's membrane complex and EZ band externally to the NIR-AF signal area.Conclusions: NIR-AF imaging confirms an early RPE involvement allowing us to identify and to quantify the RPE pigment loss in choroideremia. For this reason, NIR-AF imaging can be useful for monitoring the progression of the disease and to study the effect of future treatments.
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Affiliation(s)
- Dario Pasquale Mucciolo
- Department of Neuroscience, Psychology, Drug Research and Child Health, University of Florence, Florence, Italy
| | - Vittoria Murro
- Department of Neuroscience, Psychology, Drug Research and Child Health, University of Florence, Florence, Italy
| | - Dario Giorgio
- Department of Neuroscience, Psychology, Drug Research and Child Health, University of Florence, Florence, Italy
| | - Andrea Sodi
- Department of Neuroscience, Psychology, Drug Research and Child Health, University of Florence, Florence, Italy
| | - Ilaria Passerini
- Department of Genetic Diagnosis, Careggi Teaching Hospital, Florence, Italy
| | - Gianni Virgili
- Department of Neuroscience, Psychology, Drug Research and Child Health, University of Florence, Florence, Italy
| | - Stanislao Rizzo
- Department of Neuroscience, Psychology, Drug Research and Child Health, University of Florence, Florence, Italy
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39
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Nakamura T, Hayashi A, Oiwake T. Long-term changes of retinal pigment epithelium in the eyes with Vogt-Koyanagi-Harada disease observed by adaptive optics imaging. Clin Ophthalmol 2019; 13:927-933. [PMID: 31213764 PMCID: PMC6549749 DOI: 10.2147/opth.s199886] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2018] [Accepted: 04/26/2019] [Indexed: 01/10/2023] Open
Abstract
Purpose: To observe long-term changes of the retinal pigment epithelium (RPE) in the eyes of patients with Vogt-Koyanagi-Harada (VKH) disease using an adaptive optics (AO) fundus camera, and their correlation with the findings of spectral-domain optical coherence tomography (SD-OCT), fundus autofluorescence (AF) imaging. Patients and methods: Three eyes of two patients with new-onset acute VKH disease were retrospectively studied. After the serous retinal detachment was resolved by high-dose corticosteroid treatment, the patients were examined with SD-OCT, blue-wavelength AF, near-infrared (NIR) AF, and an AO fundus camera. AO images of the macula were obtained using the rtx1TM AO fundus camera. The area around the foveal center of the hyper-reflective lesion in AO imaging was measured manually. The time at which the serous retinal detachment resolved was set as the baseline, and AO and other images were obtained every 3 to 6 months from the baseline. Results: In all three eyes, lesions with elevation or thickening of the RPE layer were observed with OCT imaging in the macula after the serous retinal detachment resolved. These lesions showed hyper-autofluorescence in NIR-AF image and hyper-reflective lesions with clear boundaries in AO image. The area of the hyper-reflective lesions of AO images in each eye showed an approximately 40% decrease at 6 months from baseline. However, the hyper-reflective lesion remained to some extent after 18 months in case 1 and 36 months in case 2. Conclusions: By using OCT, fundus autofluorescence and AO images, it was possible to observe temporal changes of RPE layer in VKH eyes noninvasively. High-resolution AO images also allow us to observe for improvements in the elevation or thickening of the RPE layer quantitatively.
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Affiliation(s)
- Tomoko Nakamura
- Department of Ophthalmology, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama, Japan
| | - Atsushi Hayashi
- Department of Ophthalmology, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama, Japan
| | - Toshihiko Oiwake
- Department of Ophthalmology, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama, Japan
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40
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Navaratnam J, Bærland TP, Eide NA, Faber RT, Rekstad BL, Vavvas DG, Bragadóttir R. Fundus Autofluorescence Change as an Early Indicator of Treatment Effect of Brachytherapy for Choroidal Melanomas. Ocul Oncol Pathol 2019; 5:445-453. [PMID: 31768369 DOI: 10.1159/000499403] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2018] [Revised: 03/05/2019] [Indexed: 12/29/2022] Open
Abstract
Background Early confirmation of the effect of brachytherapy for choroidal melanoma showing that tumour coverage is valuable. The irradiated retinal pigment epithelium (RPE) commonly develops atrophy. This study compares the fundus autofluorescence (AF) changes to the development of RPE atrophy following brachytherapy. Methods Retrospective study of 19 patients treated with <sup>106</sup>Ru and 2 with <sup>125</sup>I plaques with either a 3- or 6-month follow-up period. Ultra-widefield (UW) composite colour and AF images were obtained with Optomap 200Tx and interpreted as complete, partial, or no RPE changes and complete or partial hyperautofluorescence, hypoautofluorescence, or isoautofluorescence. Results At the 3-month follow-up, 9 of 13 patients (69%) (95% confidence interval [CI], 0.389-0.896) treated with <sup>106</sup>Ru plaques developed complete homogenous hyperautofluorescence surrounding the tumour, but only 1 of 13 (8%) (95% CI, 0.004-0.379) developed complete RPE atrophy at the same time point. Six patients in the <sup>106</sup>Ru plaque group had their first follow-up with UW imaging at 6 months. Four of them developed homogenous hyperautofluorescence and none developed complete RPE atrophy around the tumour. The 2 patients treated with <sup>125</sup>I did not demonstrate any clear RPE or AF changes. Conclusion The effect of <sup>106</sup>Ru plaque treatment on fundus UW imaging is detected as homogenous and well-demarcated hyperautofluorescence before visible RPE atrophy.
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Affiliation(s)
- Jesintha Navaratnam
- Department of Ophthalmology, Oslo University Hospital, Oslo, Norway.,University of Oslo, Oslo, Norway
| | - Thomas P Bærland
- Department of Ophthalmology, Oslo University Hospital, Oslo, Norway
| | - Nils A Eide
- Department of Ophthalmology, Oslo University Hospital, Oslo, Norway
| | - Rowan T Faber
- Department of Ophthalmology, Oslo University Hospital, Oslo, Norway
| | - Bernt L Rekstad
- Department of Medical Physics, Oslo University Hospital, Oslo, Norway
| | - Demetrios G Vavvas
- Retina Service, Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, Massachusetts, USA
| | - Ragnheiður Bragadóttir
- Department of Ophthalmology, Oslo University Hospital, Oslo, Norway.,University of Oslo, Oslo, Norway
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