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Zhong Y, Yang Y, Zhang L, Ma D, Wen K, Cai J, Cai Z, Wang C, Chai X, Zhong J, Liang B, Huang Y, Xian H, Li Z, Yang X, Chen D, Zhang G, Huang Z. Revealing new insights: Two-center evidence of microplastics in human vitreous humor and their implications for ocular health. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 921:171109. [PMID: 38387563 DOI: 10.1016/j.scitotenv.2024.171109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2023] [Revised: 02/07/2024] [Accepted: 02/18/2024] [Indexed: 02/24/2024]
Abstract
Microplastics (MPs), an emerging environmental contaminant, have raised growing health apprehension due to their detection in various human biospecimens. Despite extensive research into their prevalence in the environment and the human body, the ramifications of their existence within the enclosed confines of the human eye remain largely unexplored. Herein, we assembled a cohort of 49 patients with four ocular diseases (macular hole, macular epiretinal membrane, retinopathy and rhegmatogenous retinal detachment) from two medical centers. After processing the samples with an optimized method, we utilized Laser Direct Infrared (LD-IR) spectroscopy and Pyrolysis Gas Chromatography/Mass Spectrometry (Py-GC/MS) to analyze 49 vitreous samples, evaluating the characteristics of MPs within the internal environment of the human eye. Our results showed that LD-IR scanned a total of 8543 particles in the composite sample from 49 individual vitreous humor samples, identifying 1745 as plastic particles, predominantly below 50 μm. Concurrently, Py-GC/MS analysis of the 49 individual samples corroborated these findings, with nylon 66 exhibiting the highest content, followed by polyvinyl chloride, and detection of polystyrene. Notably, correlations were observed between MP levels and key ocular health parameters, particularly intraocular pressure and the presence of aqueous humor opacities. Intriguingly, individuals afflicted with retinopathy demonstrated heightened ocular health risks associated with MPs. In summary, this research provides significant insights into infiltration of MP pollutants within the human eye, shedding light on their potential implications for ocular health and advocating for further exploration of this emerging health risk.
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Affiliation(s)
- Yizhou Zhong
- Translational Medicine Research Center, Zhujiang Hospital, Southern Medical University, Guangzhou 510280, China; NMPA Key Laboratory for Safety Evaluation of Cosmetics, Guangdong Provincial Key Laboratory of Tropical Disease Research, Department of Toxicology, School of Public Health, Southern Medical University, Guangzhou 510515, China
| | - Yuhang Yang
- Shenzhen Eye Hospital, Jinan University, Shenzhen 518040, China
| | - Linan Zhang
- Shenzhen Eye Hospital, Jinan University, Shenzhen 518040, China
| | - Dahui Ma
- Shenzhen Eye Hospital, Jinan University, Shenzhen 518040, China
| | - Kailiang Wen
- Meizhou city Meijiang district Shenmei Eye Hospital, Meizhou 514031, China
| | - Jiachun Cai
- Shenzhen Eye Hospital, Jinan University, Shenzhen 518040, China
| | - Zhanmou Cai
- Meizhou city Meijiang district Shenmei Eye Hospital, Meizhou 514031, China
| | - Cui Wang
- Shenzhen Eye Hospital, Jinan University, Shenzhen 518040, China
| | - Xiaoyan Chai
- Shenzhen Eye Hospital, Jinan University, Shenzhen 518040, China
| | - Jingwen Zhong
- Meizhou city Meijiang district Shenmei Eye Hospital, Meizhou 514031, China
| | - Boxuan Liang
- NMPA Key Laboratory for Safety Evaluation of Cosmetics, Guangdong Provincial Key Laboratory of Tropical Disease Research, Department of Toxicology, School of Public Health, Southern Medical University, Guangzhou 510515, China
| | - Yuji Huang
- NMPA Key Laboratory for Safety Evaluation of Cosmetics, Guangdong Provincial Key Laboratory of Tropical Disease Research, Department of Toxicology, School of Public Health, Southern Medical University, Guangzhou 510515, China
| | - Hongyi Xian
- NMPA Key Laboratory for Safety Evaluation of Cosmetics, Guangdong Provincial Key Laboratory of Tropical Disease Research, Department of Toxicology, School of Public Health, Southern Medical University, Guangzhou 510515, China
| | - Zhiming Li
- NMPA Key Laboratory for Safety Evaluation of Cosmetics, Guangdong Provincial Key Laboratory of Tropical Disease Research, Department of Toxicology, School of Public Health, Southern Medical University, Guangzhou 510515, China
| | - Xingfen Yang
- NMPA Key Laboratory for Safety Evaluation of Cosmetics, Guangdong Provincial Key Laboratory of Tropical Disease Research, Department of Toxicology, School of Public Health, Southern Medical University, Guangzhou 510515, China
| | - Da Chen
- College of Environment and Climate, Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou 510632, China
| | - Guoming Zhang
- Shenzhen Eye Hospital, Jinan University, Shenzhen 518040, China.
| | - Zhenlie Huang
- NMPA Key Laboratory for Safety Evaluation of Cosmetics, Guangdong Provincial Key Laboratory of Tropical Disease Research, Department of Toxicology, School of Public Health, Southern Medical University, Guangzhou 510515, China.
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Zengin S, Mercan S, Tarhan D, Gök A, Ercan AM. Age-related changes on physicochemical properties of the artificial vitreous humor: A practical tool for enhancing ex vivo studies. Exp Eye Res 2024; 239:109762. [PMID: 38147936 DOI: 10.1016/j.exer.2023.109762] [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: 06/08/2023] [Revised: 12/01/2023] [Accepted: 12/20/2023] [Indexed: 12/28/2023]
Abstract
The vitreous humor (VH) is a hydrophilic, jelly-like ocular fluid, which is located in the posterior chamber of the eye. The rheological, structural, and chemical properties of VH change significantly during aging, which further causes eye-associated diseases and could be a potential indicator for various diseases. In this study, artificial VH (A-VH) samples were created by taking into account different age groups to observe age-related changes in the physicochemical properties of these samples. This study aimed to measure the physicochemical properties of age-dependently prepared A-VH samples to determine the changes with aging in the physicochemical properties of A-VH samples. Phosphate-buffered saline (PBS)-based A-VH samples were prepared in three types representing adult, middle-aged, and elder individuals. Age-related changes in physicochemical properties (surface tension, osmolality, pH, relative viscosity, density, and refractive index) were analyzed by related equipment. The A-VH samples, prepared using PBS, showed strong similarity to authentic VH in terms of physicochemical properties. While the age-related changes studies have revealed some discrepancies between age-dependently prepared A-VH samples in terms of surface tension, osmolality, relative viscosity, and pH with high correlation coefficients (r2 > 0,94), density and refractive index values did not show any significant differences and correlation between types of A-VH representing 3 age groups. In conclusion, age-dependent A-VH samples were created successfully to use ex vivo method development studies, and the influence of aging on the physicochemical properties of VH was demonstrated as well.
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Affiliation(s)
- Simge Zengin
- Istanbul University-Cerrahpaşa, Institute of Forensic Sciences and Legal Medicine, Department of Science, Buyukcekmece, Istanbul, Turkey
| | - Selda Mercan
- Istanbul University-Cerrahpaşa, Institute of Forensic Sciences and Legal Medicine, Department of Science, Buyukcekmece, Istanbul, Turkey.
| | - Duygu Tarhan
- Bahcesehir University, School of Medicine, Department of Biophysics, Goztepe, Istanbul, Turkey
| | - Aslı Gök
- Istanbul University-Cerrahpaşa, Faculty of Engineering, Department of Chemical Engineering, Avcılar, Istanbul, Turkey
| | - Alev Meltem Ercan
- Istanbul University-Cerrahpaşa, Cerrahpaşa Faculty of Medicine, Department of Biophysics, Fatih, Istanbul, Turkey
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Ghorbani R, Rasouli M, Sefat F, Heidari Keshel S. Pathogenesis of Common Ocular Diseases: Emerging Trends in Extracellular Matrix Remodeling. Semin Ophthalmol 2024; 39:27-39. [PMID: 37424085 DOI: 10.1080/08820538.2023.2233601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Revised: 06/27/2023] [Accepted: 07/02/2023] [Indexed: 07/11/2023]
Abstract
The prevalence of visual impairments in human societies is worrying due to retinopathy complications of several chronic diseases such as diabetes, cardiovascular diseases, and many more that are on the rise worldwide. Since the proper function of this organ plays a pivotal role in people's quality of life, identifying factors affecting the development/exacerbation of ocular diseases is of particular interest among ophthalmology researchers. The extracellular matrix (ECM) is a reticular, three-dimensional (3D) structure that determines the shape and dimensions of tissues in the body. The ECM remodeling/hemostasis is a critical process in both physiological and pathological conditions. It consists of ECM deposition, degradation, and decrease/increase in the ECM components. However, disregulation of this process and an imbalance between the synthesis and degradation of ECM components are associated with many pathological situations, including ocular disorders. Despite the impact of ECM alterations on the development of ocular diseases, there is not much research conducted in this regard. Therefore, a better understanding in this regard, can pave the way toward discovering plausible strategies to either prevent or treat eye disorders. In this review, we will discuss the importance of ECM changes as a sentimental factor in various ocular diseases based on the research done up to now.
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Affiliation(s)
- Raziyeh Ghorbani
- Department of Tissue Engineering and Applied Cell Sciences, School of Advanced Technologies in Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mehdi Rasouli
- Department of Tissue Engineering and Applied Cell Sciences, School of Advanced Technologies in Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Farshid Sefat
- Department of Biomedical and Electronics Engineering, School of Engineering, University of Bradford, Bradford, UK
- Interdisciplinary Research Centre in Polymer Science & Technology (Polymer IRC), University of Bradford, Bradford, UK
| | - Saeed Heidari Keshel
- Department of Tissue Engineering and Applied Cell Sciences, School of Advanced Technologies in Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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Ożóg MK, Nowak-Wąs M, Rokicki W. Pathophysiology and clinical aspects of epiretinal membrane - review. Front Med (Lausanne) 2023; 10:1121270. [PMID: 37636571 PMCID: PMC10447902 DOI: 10.3389/fmed.2023.1121270] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2022] [Accepted: 07/24/2023] [Indexed: 08/29/2023] Open
Abstract
The epiretinal membrane (ERM) is a pathological tissue formed at the vitreoretinal interface. The formation of this tissue is associated with numerous symptoms related to disturbances of vision. These types of lesions may arise idiopathically or be secondary to eye diseases, injuries and retinal surgeries. ERM tissue contains numerous cell types and numerous cytokines, which participate in its formation. The aim of this paper is to summarize information about the etiology, epidemiology, pathophysiology and treatment of ERM, with a brief description of the main cells that build the ERM - as well as the cytokines and molecules related to ERM pathogenesis - being provided in addition.
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Affiliation(s)
- Mateusz Kamil Ożóg
- Department of Histology and Cell Pathology, Faculty of Medical Sciences in Zabrze, Medical University of Silesia, Katowice, Poland
- Department of Histology, Cytophysiology and Embryology, Faculty of Medicine, Academy of Silesia, Zabrze, Poland
| | - Marta Nowak-Wąs
- Department of Histology and Cell Pathology, Faculty of Medical Sciences in Zabrze, Medical University of Silesia, Katowice, Poland
- Department of Ophthalmology, Kornel Gibiński University Clinical Center, Medical University of Silesia, Katowice, Poland
| | - Wojciech Rokicki
- Department of Ophthalmology, Kornel Gibiński University Clinical Center, Medical University of Silesia, Katowice, Poland
- Department of Ophthalmology, Faculty of Medical Sciences in Katowice, Medical University of Silesia, Katowice, Poland
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Zhang R, Li B, Li H. Extracellular-Matrix Mechanics Regulate the Ocular Physiological and Pathological Activities. J Ophthalmol 2023; 2023:7626920. [PMID: 37521908 PMCID: PMC10386902 DOI: 10.1155/2023/7626920] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Revised: 07/06/2023] [Accepted: 07/13/2023] [Indexed: 08/01/2023] Open
Abstract
The extracellular matrix (ECM) is a noncellular structure that plays an indispensable role in a series of cell life activities. Accumulating studies have demonstrated that ECM stiffness, a type of mechanical forces, exerts a pivotal influence on regulating organogenesis, tissue homeostasis, and the occurrence and development of miscellaneous diseases. Nevertheless, the role of ECM stiffness in ophthalmology is rarely discussed. In this review, we focus on describing the important role of ECM stiffness and its composition in multiple ocular structures (including cornea, retina, optic nerve, trabecular reticulum, and vitreous) from a new perspective. The abnormal changes in ECM can trigger physiological and pathological activities of the eye, suggesting that compared with different biochemical factors, the transmission and transduction of force signals triggered by mechanical cues such as ECM stiffness are also universal in different ocular cells. We expect that targeting ECM as a therapeutic approach or designing advanced ECM-based technologies will have a broader application prospect in ophthalmology.
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Affiliation(s)
- Ran Zhang
- Department of Ophthalmology & Optometry, North Sichuan Medical College, Nanchong 637000, Sichuan, China
- Department of Ophthalmology, Central Hospital of Suining City, Suining 629000, Sichuan, China
| | - Bo Li
- Department of Ophthalmology, Central Hospital of Suining City, Suining 629000, Sichuan, China
| | - Heng Li
- Department of Ophthalmology & Optometry, North Sichuan Medical College, Nanchong 637000, Sichuan, China
- Department of Ophthalmology, Central Hospital of Suining City, Suining 629000, Sichuan, China
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6
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Zu H, Zhang K, Zhang H, Qian X. An Inverse Method to Determine Mechanical Parameters of Porcine Vitreous Bodies Based on the Indentation Test. Bioengineering (Basel) 2023; 10:646. [PMID: 37370577 DOI: 10.3390/bioengineering10060646] [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: 04/20/2023] [Revised: 05/16/2023] [Accepted: 05/23/2023] [Indexed: 06/29/2023] Open
Abstract
The vitreous body keeps the lens and retina in place and protects these tissues from physical insults. Existing studies have reported that the mechanical properties of vitreous body varied after liquefaction, suggesting mechanical properties could be effective parameters to identify vitreous liquefaction process. Thus, in this work, we aimed to propose a method to determine the mechanical properties of vitreous bodies. Fresh porcine eyes were divided into three groups, including the untreated group, the 24 h liquefaction group and the 48 h liquefaction group, which was injected collagenase and then kept for 24 h or 48 h. The indentation tests were carried out on the vitreous body in its natural location while the posterior segment of the eye was fixed in the container. A finite element model of a specimen undertaking indentation was constructed to simulate the indentation test with surface tension of vitreous body considered. Using the inverse method, the mechanical parameters of the vitreous body and the surface tension coefficient were determined. For the same parameter, values were highest in the untreated group, followed by the 24 h liquefaction group and the lowest in the 48 h liquefaction group. For C10 in the neo-Hookean model, the significant differences were found between the untreated group and liquefaction groups. This work quantified vitreous body mechanical properties successfully using inverse method, which provides a new method for identifying vitreous liquefactions related studies.
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Affiliation(s)
- Haicheng Zu
- School of Biomedical Engineering, Capital Medical University, Beijing 100069, China
| | - Kunya Zhang
- School of Biomedical Engineering, Capital Medical University, Beijing 100069, China
- Beijing Key Laboratory of Fundamental Research on Biomechanics in Clinical Application, Capital Medical University, Beijing 100069, China
| | - Haixia Zhang
- School of Biomedical Engineering, Capital Medical University, Beijing 100069, China
- Beijing Key Laboratory of Fundamental Research on Biomechanics in Clinical Application, Capital Medical University, Beijing 100069, China
| | - Xiuqing Qian
- School of Biomedical Engineering, Capital Medical University, Beijing 100069, China
- Beijing Key Laboratory of Fundamental Research on Biomechanics in Clinical Application, Capital Medical University, Beijing 100069, China
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Tomiyasu M, Sahara Y, Mitsui E, Tsuchiya H, Maeda T, Tomoyori N, Kawashima M, Nogawa T, Kishimoto R, Takado Y, Higashi T, Mizota A, Kudo K, Obata T. Intraocular Water Movement Visualization Using 1 H-MRI With Eye Drops of O-17-Labeled Saline: First-in-Human Study. J Magn Reson Imaging 2023; 57:845-853. [PMID: 35838084 DOI: 10.1002/jmri.28345] [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: 04/14/2022] [Revised: 06/21/2022] [Accepted: 06/22/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Visualization of aqueous humor flow in MR contrast images using gadolinium is challenging because of the delayed contrast effects associated with the blood-retinal and blood-aqueous humor barriers. However, oxygen-17 water (H2 17 O) might be used as an ocular contrast agent. PURPOSE To observe the distribution of H2 17 O in the human eye, and its flow in and out of the anterior chamber, using dynamic T2-weighted MRI. STUDY TYPE Prospective. POPULATION Six ophthalmologically normal volunteers (20-37 years, six females). FIELD STRENGTH/SEQUENCE A 3 T/dynamic T2-weighted MRI. ASSESSMENT H2 17 O eye drops were administered to the right eye. Time-series images were created by subtracting the image before the eye drops from each of the images obtained after the eye drops. The normalized signal intensity of the right anterior chamber (nAC) was obtained by dividing the signal intensity of the right anterior chamber region by that of the left. The inflow and outflow constants of H2 17 O and H2 17 O concentration were calculated from the nAC. STATISTICAL TESTS A paired t-test was used to compare the flow-related values and temporal changes in signal intensity. P-values < 0.05 were considered statistically significant. RESULTS Significantly decreased signal intensity was observed in the right anterior chamber but not the right vitreous body (P = 0.39). The nAC signal intensity decreased significantly and then recovered. The inflow and outflow constants were 0.36-0.94 min-1 and 0.023-0.13 min-1 , respectively. The maximum H2 17 O concentration was 0.078%-0.24%. DATA CONCLUSION H2 17 O were distributed in the anterior chamber. The H2 17 O inflow into the anterior chamber was significantly faster than that of the outflow. LEVEL OF EVIDENCE 2 TECHNICAL EFFICACY STAGE: 2.
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Affiliation(s)
- Moyoko Tomiyasu
- Department of Molecular Imaging and Theranostics, National Institutes for Quantum Science and Technology, Chiba, Japan
| | - Yasuka Sahara
- Department of Molecular Imaging and Theranostics, National Institutes for Quantum Science and Technology, Chiba, Japan
| | - Etsuko Mitsui
- Department of Molecular Imaging and Theranostics, National Institutes for Quantum Science and Technology, Chiba, Japan
| | - Hiroki Tsuchiya
- Department of Medical Technology, National Institutes for Quantum Science and Technology, Chiba, Japan
| | - Takamasa Maeda
- Department of Medical Technology, National Institutes for Quantum Science and Technology, Chiba, Japan
| | | | | | - Toshifumi Nogawa
- Preventive Dentistry, Hokkaido University Hospital, Sapporo, Japan
| | - Riwa Kishimoto
- Department of Radiology, National Institutes for Quantum Science and Technology, Chiba, Japan
| | - Yuhei Takado
- Institute of Quantum Life Science, National Institutes for Quantum Science and Technology, Chiba, Japan
| | - Tatsuya Higashi
- Department of Molecular Imaging and Theranostics, National Institutes for Quantum Science and Technology, Chiba, Japan
| | - Atsushi Mizota
- Department of Ophthalmology, Teikyo University, Tokyo, Japan
| | - Kohsuke Kudo
- Department of Diagnostic Imaging, Hokkaido University Faculty of Medicine, Sapporo, Japan
| | - Takayuki Obata
- Department of Molecular Imaging and Theranostics, National Institutes for Quantum Science and Technology, Chiba, Japan
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Vitreous Substitutes from Bench to the Operating Room in a Translational Approach: Review and Future Endeavors in Vitreoretinal Surgery. Int J Mol Sci 2023; 24:ijms24043342. [PMID: 36834754 PMCID: PMC9961686 DOI: 10.3390/ijms24043342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Revised: 01/24/2023] [Accepted: 02/02/2023] [Indexed: 02/11/2023] Open
Abstract
Vitreous substitutes are indispensable tools in vitreoretinal surgery. The two crucial functions of these substitutes are their ability to displace intravitreal fluid from the retinal surface and to allow the retina to adhere to the retinal pigment epithelium. Today, vitreoretinal surgeons can choose among a plethora of vitreous tamponades, and the tamponade of choice might be difficult to determine in the ever-expanding range of possibilities for a favorable outcome. The currently available vitreous substitutes have disadvantages that need to be addressed to improve the surgical outcome achievable today. Herein, the fundamental physical and chemical proprieties of all vitreous substitutes are reported, and their use and clinical applications are described alongside some surgical techniques of intra-operative manipulation. The major upcoming developments in vitreous substitutes are extensively discussed, keeping a translational perspective throughout. Conclusions on future perspectives are derived through an in-depth analysis of what is lacking today in terms of desired outcomes and biomaterials technology.
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Mishra D, Gade S, Glover K, Sheshala R, Singh TRR. Vitreous Humor: Composition, Characteristics and Implication on Intravitreal Drug Delivery. Curr Eye Res 2023; 48:208-218. [PMID: 36036478 DOI: 10.1080/02713683.2022.2119254] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Purpose: Intravitreal administration of drug molecules is one of the most common routes for treating posterior segment eye diseases. However, the properties of vitreous humour changes with the time. A number of ocular complications such as liquefaction of the vitreous humour, solidification of the vitreous humour in the central vitreous cavity and detachment of the limiting membrane due to the shrinking of vitreous humour are some of the factors that can drastically affect the efficacy of therapeutics delivered via intravitreal route. Although significant research has been conducted for studying the properties of vitreous humour and its changes during the ageing process, there have been limited work to understand the effect of these changes on therapeutic efficacy of intravitreal drug delivery systems. Therefore, in this review we discussed both the coomposition and characteristics of the vitreous humour, and their subsequent influence on intravitreal drug delivery.Methods: Articles were searched on Scopus, PubMed and Web of Science up to March 2022.Results: In this review, we discussed the biological composition and biomechanical properties of vitreous humour, methods to study the properties of vitreous humour and the changes in these properties and their relevance in ocular drug delivery field, with the aim to provide a useful insight into these aspects which can aid the process of development of novel intravitreal drug delivery systems.Conclusions: The composition and characteristics of the vitreous humour, and how these change during natural aging processes, directly influence intravitreal drug delivery. This review therefore highlights the importance of understanding the properties of the vitreous and identifies the need to achieve greater understanding of how changing properties of the vitreous affect the therapeutic efficacy of drugs administered for the treatment of posterior eye diseases.
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Affiliation(s)
- Deepakkumar Mishra
- School of Pharmacy, Medical Biology Centre, Queen's University Belfast, Belfast, UK
| | - Shilpkala Gade
- School of Pharmacy, Medical Biology Centre, Queen's University Belfast, Belfast, UK
| | - Katie Glover
- School of Pharmacy, Medical Biology Centre, Queen's University Belfast, Belfast, UK
| | - Ravi Sheshala
- Faculty of Pharmacy, Research Group of Affinity, Safety and Efficacy Studies (OASES), Universiti Teknologi MARA Selangor, Kuala Selangor, Malaysia
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10
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Creveling CJ, Alsanea Y, Coats B. Correlation of collagen fibril properties and inner limiting membrane thickness with vitreoretinal adhesion in human eyes. Exp Eye Res 2022; 223:109189. [PMID: 35868365 PMCID: PMC9553025 DOI: 10.1016/j.exer.2022.109189] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Revised: 06/10/2022] [Accepted: 07/06/2022] [Indexed: 02/02/2023]
Abstract
Vitreoretinal adhesive strength is thought to play a mechanical role in various retinal diseases; however, collagen fibril properties and inner limiting membrane (ILM) thickness have not been quantitatively correlated to adhesive strength. In this work, we quantified the relationship between collagen fibril density, angle, length, and ILM thickness with vitreoretinal adhesive strength to advance our understanding of structure-function relationships in vitreoretinal adhesion. Following mechanical peel tests, human retinal sections from the equator and posterior pole of donors 42-89 years of age were extracted and processed for transmission electron microscopy. Collagen fibrils at the vitreoretinal interface were segmented and fibril density, angle, length, and ILM thickness quantified. Morphological measurements were correlated with vitreoretinal adhesion measured in the same location. We found that collagen fibril density was 1.6 times greater in the equator compared to the posterior pole across all ages (p=0.0305). Steady-state peel force showed a slight positive correlation with increasing density in both the equator and posterior pole, but was only statistically significant in the equator (p<0.05). Collagen fibril angle and length did not significantly vary with age or region. ILM thickness was 3.8 times thicker in the posterior pole compared to the equator (p<0.0001). ILM thickness was 1.8 times greater in eyes ≤60 years of age compared to eyes >60 of age (p=0.0136). Maximum peel force was significantly correlated with increasing ILM thickness in the equator (p=0.015). A similar trend was seen in the posterior pole, but this was not significant. These data suggest that collagen contributes to adhesion at the vitreoretinal interface, but the structure of the ILM is more influential on the initiation of separation between the vitreous and retina.
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Affiliation(s)
- C J Creveling
- Department of Mechanical Engineering, University of Utah, 1495 E 100 S, Salt Lake City, 84112, United States.
| | - Y Alsanea
- Department of Mechanical Engineering, University of Utah, 1495 E 100 S, Salt Lake City, 84112, United States.
| | - B Coats
- Department of Mechanical Engineering, University of Utah, 1495 E 100 S, Salt Lake City, 84112, United States.
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Phillips JD, Hwang ES, Morgan DJ, Creveling CJ, Coats B. Structure and mechanics of the vitreoretinal interface. J Mech Behav Biomed Mater 2022; 134:105399. [PMID: 35963021 PMCID: PMC9552593 DOI: 10.1016/j.jmbbm.2022.105399] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Revised: 07/17/2022] [Accepted: 07/24/2022] [Indexed: 12/24/2022]
Abstract
Vitreoretinal mechanics plays an important role in retinal trauma and many sight-threatening diseases. In age-related pathologies, such as posterior vitreous detachment and vitreomacular traction, lingering vitreoretinal adhesions can lead to macular holes, epiretinal membranes, retinal tears and detachment. In age-related macular degeneration, vitreoretinal traction has been implicated in the acceleration of the disease due to the stimulation of vascular growth factors. Despite this strong mechanobiological influence on trauma and disease in the eye, fundamental understanding of the mechanics at the vitreoretinal interface is limited. Clarification of adhesion mechanisms and the role of vitreoretinal mechanics in healthy eyes and disease is necessary to develop innovative treatments for these pathologies. In this review, we evaluate the existing literature on the structure and function of the vitreoretinal interface to gain insight into age- and region-dependent mechanisms of vitreoretinal adhesion. We explore the role of vitreoretinal adhesion in ocular pathologies to identify knowledge gaps and future research areas. Finally, we recommend future mechanics-based studies to address the critical needs in the field, increase fundamental understanding of vitreoretinal mechanisms and disease, and inform disease treatments.
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Affiliation(s)
- Joseph D Phillips
- Department of Mechanical Engineering, University of Utah, Salt Lake City, UT, United States
| | - Eileen S Hwang
- Department of Ophthalmology and Visual Sciences, University of Utah, Salt Lake City, UT, United States
| | - Denise J Morgan
- Department of Ophthalmology and Visual Sciences, University of Utah, Salt Lake City, UT, United States
| | | | - Brittany Coats
- Department of Mechanical Engineering, University of Utah, Salt Lake City, UT, United States.
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12
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Liu W, Li S, Wang B, Peng P, Gao C. Physiologically Responsive Polyurethanes for Tissue Repair and Regeneration. ADVANCED NANOBIOMED RESEARCH 2022. [DOI: 10.1002/anbr.202200061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Affiliation(s)
- Wenxing Liu
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and Engineering Zhejiang University Hangzhou 310027 China
| | - Shifen Li
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and Engineering Zhejiang University Hangzhou 310027 China
| | - Beiduo Wang
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and Engineering Zhejiang University Hangzhou 310027 China
| | - Pai Peng
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and Engineering Zhejiang University Hangzhou 310027 China
| | - Changyou Gao
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and Engineering Zhejiang University Hangzhou 310027 China
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13
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Complications of Treatment for Symptomatic Vitreous Floaters: A Review. Int Ophthalmol Clin 2022; 62:131-155. [PMID: 35752891 DOI: 10.1097/iio.0000000000000433] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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14
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Srikantha N, Teijeiro-Gonzalez Y, Simpson A, Elsaid N, Somavarapu S, Suhling K, Jackson TL. Determining vitreous viscosity using fluorescence recovery after photobleaching. PLoS One 2022; 17:e0261925. [PMID: 35143514 PMCID: PMC8830689 DOI: 10.1371/journal.pone.0261925] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2021] [Accepted: 12/14/2021] [Indexed: 01/22/2023] Open
Abstract
PURPOSE Vitreous humor is a complex biofluid whose composition determines its structure and function. Vitreous viscosity will affect the delivery, distribution, and half-life of intraocular drugs, and key physiological molecules. The central pig vitreous is thought to closely match human vitreous viscosity. Diffusion is inversely related to viscosity, and diffusion is of fundamental importance for all biochemical reactions. Fluorescence Recovery After Photobleaching (FRAP) may provide a novel means of measuring intravitreal diffusion that could be applied to drugs and physiological macromolecules. It would also provide information about vitreous viscosity, which is relevant to drug elimination, and delivery. METHODS Vitreous viscosity and intravitreal macromolecular diffusion of fluorescently labelled macromolecules were investigated in porcine eyes using fluorescence recovery after photobleaching (FRAP). Fluorescein isothiocyanate conjugated (FITC) dextrans and ficolls of varying molecular weights (MWs), and FITC-bovine serum albumin (BSA) were employed using FRAP bleach areas of different diameters. RESULTS The mean (±standard deviation) viscosity of porcine vitreous using dextran, ficoll and BSA were 3.54 ± 1.40, 2.86 ± 1.13 and 4.54 ± 0.13 cP respectively, with an average of 3.65 ± 0.60 cP. CONCLUSIONS FRAP is a feasible and practical optical method to quantify the diffusion of macromolecules through vitreous.
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Affiliation(s)
- Nishanthan Srikantha
- School of Medicine, King’s College London, London, United Kingdom
- Department of Ophthalmology, King’s College Hospital, London, United Kingdom
- * E-mail:
| | | | - Andrew Simpson
- School of Medicine, King’s College London, London, United Kingdom
- Department of Ophthalmology, King’s College Hospital, London, United Kingdom
| | - Naba Elsaid
- Anglia Ruskin University, Bishop Hall Lane, Chelmsford, United Kingdom
| | - Satyanarayana Somavarapu
- Department of Pharmaceutics, University College London School of Pharmacy, London, United Kingdom
| | - Klaus Suhling
- Department of Physics, King’s College London, Strand, London, United Kingdom
| | - Timothy L. Jackson
- School of Medicine, King’s College London, London, United Kingdom
- Department of Ophthalmology, King’s College Hospital, London, United Kingdom
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15
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Itakura H, Itakura M, Sato T. STARDUST SIGN AND RETINAL TEAR DETECTION ON SWEPT SOURCE OPTICAL COHERENCE TOMOGRAPHY. Retina 2022; 42:336-339. [PMID: 35050930 PMCID: PMC8765212 DOI: 10.1097/iae.0000000000003317] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE The causes of floaters include posterior vitreous detachment and fundus hemorrhage, both of which are risk factors for retinal tears. We observed the vitreous of patients with floaters using swept source optical coherence tomography. METHODS Fundus examination was performed, and the vitreous was observed using swept source optical coherence tomography in 202 eyes of 202 patients with floaters. Patients with uveitis, diabetic retinopathy, and other fundus diseases were excluded. RESULTS Swept source optical coherence tomography revealed posterior vitreous detachment in 145 of 202 eyes (71.8%) and dot reflex like stardust in the vitreous in 42 of 202 eyes (20.8%). Posterior vitreous detachment occurred in 35 of 42 eyes (83.3%) and 110 of 160 eyes (68.8%) in the stardust (+) and stardust (-) groups, respectively; a significant difference was observed (P <0.001). In the stardust (+) group, 11 of 42 eyes (26.2%) had retinal tears with posterior vitreous detachment and 21 of 42 eyes (50.0%) had fundus hemorrhage. Three of 160 eyes (1.9%) and 4 of 160 eyes (2.5%) in the stardust (-) group had retinal tears with posterior vitreous detachment and fundus hemorrhage, respectively. Both tears and fundus hemorrhage were more frequent in the stardust (+) group than in the stardust (-) group (P <0.001). CONCLUSION The stardust sign on swept source optical coherence tomography indicates the risk of retinal tear.
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Affiliation(s)
| | - Mariko Itakura
- Maebashi Minami Eye Clinic, Maebashi-city, Gunma, Japan; and
| | - Taku Sato
- Takasaki Sato Eye Clinic, Takasaki, Gunma, Japan
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16
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Elmali A, Koc I, Ciftci SY, Nemutlu E, Surucu S, Kiratli H, Yuce D, Cengiz M, Zorlu F, Ozyigit G, Yazici G. Radiotherapy-induced alterations in vitreous humor: A new potential critical structure. Exp Eye Res 2021; 212:108802. [PMID: 34688623 DOI: 10.1016/j.exer.2021.108802] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Revised: 10/06/2021] [Accepted: 10/19/2021] [Indexed: 12/28/2022]
Abstract
Vitreous humor (VH) is not considered as a critical structure in the radiotherapy planning process. In the present study, an experimental animal model was performed to examine the effects of radiotherapy on VH. The right eyes of twelve New Zealand rabbits were irradiated to 60 Gy in 3 fractions in accordance with the scheme used in the treatment of uveal melanoma in our clinic, and contralateral (left) eyes were considered as control. Weekly ophthalmologic examination was performed after irradiation, for three months. At the end of the third month, enucleation and vitreous collection were conducted. The vitreous samples were subjected to metabolomic analyses, ELISA analyses, viscosity measurements, and electron microscopic examination. In control and experimental vitreous samples, 275 different metabolites were identified, and 34 were found to differ significantly between groups. In multivariate analyzes, a clear distinction was observed between control and irradiated vitreous samples. Pathway analysis revealed that nine pathways were affected, and these pathways were mainly related to amino acid metabolism. A significant decrease was observed in the expressions of type II, V, and XI collagens in protein level in the ELISA. There was a non-significant decrease in type IX collagen and viscosity. Electron microscopic examination revealed disrupted collagen fibrillar ultra-structure and dispersed collagen fragments in the experimental vitreous. An intact vitreous is essential for a healthy eye. In this study, we observed that radiation causes changes in the vitreous that may have long-term consequences.
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Affiliation(s)
- Aysenur Elmali
- Department of Radiation Oncology, Hacettepe University, Faculty of Medicine, Ankara, Turkey.
| | - Irem Koc
- Department of Ophthalmology, Hacettepe University, Faculty of Medicine, Ankara, Turkey.
| | | | - Emirhan Nemutlu
- Department of Analytical Chemistry, Hacettepe University, Faculty of Pharmacy, Ankara, Turkey.
| | - Selcuk Surucu
- Department of Anatomy, Koc University, Faculty of Medicine, Istanbul, Turkey.
| | - Hayyam Kiratli
- Department of Ophthalmology, Hacettepe University, Faculty of Medicine, Ankara, Turkey.
| | - Deniz Yuce
- Department of Preventive Oncology, Hacettepe University, Faculty of Medicine, Ankara, Turkey.
| | - Mustafa Cengiz
- Department of Radiation Oncology, Hacettepe University, Faculty of Medicine, Ankara, Turkey.
| | - Faruk Zorlu
- Department of Radiation Oncology, Hacettepe University, Faculty of Medicine, Ankara, Turkey.
| | - Gokhan Ozyigit
- Department of Radiation Oncology, Hacettepe University, Faculty of Medicine, Ankara, Turkey.
| | - Gozde Yazici
- Department of Radiation Oncology, Hacettepe University, Faculty of Medicine, Ankara, Turkey.
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17
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Immune responses to injury and their links to eye disease. Transl Res 2021; 236:52-71. [PMID: 34051364 PMCID: PMC8380715 DOI: 10.1016/j.trsl.2021.05.005] [Citation(s) in RCA: 55] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 05/12/2021] [Accepted: 05/24/2021] [Indexed: 12/31/2022]
Abstract
The eye is regarded as an immune privileged site. Since the presence of a vasculature would impair vision, the vasculature of the eye is located outside of the central light path. As a result, many regions of the eye evolved mechanisms to deliver immune cells to sites of dysgenesis, injury, or in response to the many age-related pathologies. While the purpose of these immune responses is reparative or protective, cytokines released by immune cells compromise visual acuity by inducing inflammation and fibrosis. The response to traumatic or pathological injury is distinct in different regions of the eye. Age-related diseases impact both the anterior and posterior segment and lead to reduced quality of life and blindness. Here we focus attention on the role that inflammation and fibrosis play in the progression of age-related pathologies of the cornea and the lens as well as in glaucoma, the formation of epiretinal membranes, and in proliferative vitreoretinopathy.
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Key Words
- 2ryERM
- A T-helper cell that expresses high levels of IL-17 which can suppress T-regulatory cell function
- A cytokine expressed early during inflammation that attracts neutrophils
- A cytokine expressed early during inflammation that attracts neutrophils, sometimes referred to as monocyte chemoattractant protein-1 (MCP-1))
- A mouse model that lacks functional T and B cells and used to study the immune response
- A pigmented mouse strain used for research and known to mount a primarily Th1 response to infection
- A protein encoded by the ADGRE1 gene that, in mice, is expressed primarily on macrophages
- A strain of pigmented mice used in glaucoma research
- ACAID
- APCs
- ASC
- An albino mouse strain used for research and known to mount a primarily Th2 response to infection
- Antigen Presenting Cells, this class includes dendritic cells and monocytes
- BALB/c
- BM
- C57BL6
- CCL2
- CD45
- CNS
- CXCL1
- Central Nervous System
- Cluster of differentiation 45 antigen
- DAMPs
- DBA/2J
- EBM
- ECM
- EMT
- ERM
- Epithelial Basement Membrane
- F4/80
- FGF2
- HA =hyaluronic acid
- HSK
- HSP
- HSPGs
- HSV
- ICN
- IL-20
- IL6
- ILM
- IOP
- Inner (or internal) limiting membrane
- Interleukin 6
- Interleukin-20
- MAGP1
- MHC-II
- Major histocompatibility complex type II, a class of MHC proteins typically found only on APCs
- Microfibril-associated glycoprotein 1
- N-cad
- N-cadherin
- NEI
- NK
- National Eye Institute
- Natural killer T cells
- PCO
- PDGF
- PDR
- PVD
- PVR
- Platelet derived growth factor
- Posterior capsular opacification
- RGC
- RPE
- RRD
- Rag1-/-
- Retinal ganglion cells
- Retinal pigment epithelial cells
- SMAD
- Sons of Mothers Against Decapentaplegic, SMADs are a class of molecules that mediate TGF and bone morphogenetic protein signaling
- T-helper cell 1 response, proinflammatory adaptive response involving interferon gamma and associated with autoimmunity
- T-helper cell 2 response involving IgE and interleukins 4,5, and 13, also induces the anti-inflammatory interleukin 10 family cytokines
- T-regulatory cell
- TG
- TGF1
- TM
- TNF
- Th1
- Th17
- Th2
- Transforming growth factor 1
- Treg
- Tumor necrosis factor a cytokine produced during inflammation
- VEGF
- Vascular endothelial growth factor
- WHO
- World Health Organization
- anterior chamber immune deviation
- anterior subcapsular cataracts
- basement membrane
- damage-associated molecular patterns
- epiretinal membrane
- epiretinal membrane secondary to disease pathology
- epithelial-mesenchymal transition
- extracellular matrix
- fibroblast growth factor 2, also referred to as basic FGF
- heat shock protein
- heparan sulfate proteoglycans
- herpes simplex virus
- herpes stromal keratitis
- iERM
- idiopathic epiretinal membrane
- intraepithelial corneal nerves
- intraocular pressure
- mTOR
- mechanistic target of rapamycin, a protein kinase encoded by the MTOR genes that regulates a variety of signal transduction events including cell growth, autophagy and actin cytoskeleton
- posterior vitreous detachment
- proliferative diabetic retinopathy
- proliferative vitreoretinopathy
- rhegmatogenous (rupture, tear) retinal detachment
- trabecular meshwork
- trigeminal ganglion
- αSMA
- α−Smooth muscle actin, a class of actin expressed in mesenchymal cells
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18
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Matyushchenko AG, Budzinskaya MV, Petrachkov DV. [Modern understanding of structural and biochemical characteristics of the vitreous in eyes with normal and increased axial length]. Vestn Oftalmol 2021; 137:110-115. [PMID: 34410065 DOI: 10.17116/oftalma2021137041110] [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: 11/18/2022]
Abstract
The review highlights the features of molecular, morphological and anatomical organization of the vitreous body in normal human eyes and in eyes with elongated anterior-posterior axis. The molecular structure of the vitreous consists of various types of collagen, glycosaminoglycans, glycoproteins and proteoglycans. The lowest concentration of collagen fibrils is in the central vitreous, so the structural changes of vitreous gel associated with attenuation of the vitreous body happen there much earlier and to a greater degree. Increased aggregation of collagen fibrils with age casuses an increase of liquid fractions of the vitreous with a concomitant decrease in gel volume. Similar processes occur earlier in eyes with axial myopia. Destructive processes in myopia increase progressively with axial elongation. As a result of vitreous collapse, vitreoretinal adhesion weakens and posterior vitreous detachment occurs.
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19
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Adrianto MF, Annuryanti F, Wilson CG, Sheshala R, Thakur RRS. In vitro dissolution testing models of ocular implants for posterior segment drug delivery. Drug Deliv Transl Res 2021; 12:1355-1375. [PMID: 34382178 PMCID: PMC9061687 DOI: 10.1007/s13346-021-01043-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/04/2021] [Indexed: 12/19/2022]
Abstract
The delivery of drugs to the posterior segment of the eye remains a tremendously difficult task. Prolonged treatment in conventional intravitreal therapy requires injections that are administered frequently due to the rapid clearance of the drug molecules. As an alternative, intraocular implants can offer drug release for long-term therapy. However, one of the several challenges in developing intraocular implants is selecting an appropriate in vitro dissolution testing model. In order to determine the efficacy of ocular implants in drug release, multiple in vitro test models were emerging. While these in vitro models may be used to analyse drug release profiles, the findings may not predict in vivo retinal drug exposure as this is influenced by metabolic and physiological factors. This review considers various types of in vitro test methods used to test drug release of ocular implants. Importantly, it discusses the challenges and factors that must be considered in the development and testing of the implants in an in vitro setup.
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Affiliation(s)
- Muhammad Faris Adrianto
- School of Pharmacy, Medical Biology Centre, Queen's University Belfast, 97 Lisburn Road, Belfast, BT9 7BL, UK.,Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Universitas Airlangga, Surabaya, East Java, 60115, Indonesia
| | - Febri Annuryanti
- School of Pharmacy, Medical Biology Centre, Queen's University Belfast, 97 Lisburn Road, Belfast, BT9 7BL, UK.,Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Universitas Airlangga, Surabaya, East Java, 60115, Indonesia
| | - Clive G Wilson
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, 161 Cathedral Street, Glasgow, G4 0RE, Scotland
| | - Ravi Sheshala
- Department of Pharmaceutics, Faculty of Pharmacy, Universiti Teknologi MARA Selangor, Puncak Alam Campus, 42300, Bandar Puncak Alam, Kuala Selangor, Malaysia
| | - Raghu Raj Singh Thakur
- School of Pharmacy, Medical Biology Centre, Queen's University Belfast, 97 Lisburn Road, Belfast, BT9 7BL, UK.
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20
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Escandon P, Vasini B, Whelchel AE, Nicholas SE, Matlock HG, Ma JX, Karamichos D. The role of peroxisome proliferator-activated receptors in healthy and diseased eyes. Exp Eye Res 2021; 208:108617. [PMID: 34010603 PMCID: PMC8594540 DOI: 10.1016/j.exer.2021.108617] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Revised: 05/03/2021] [Accepted: 05/05/2021] [Indexed: 12/23/2022]
Abstract
Peroxisome Proliferator-Activated Receptors (PPARs) are a family of nuclear receptors that play essential roles in modulating cell differentiation, inflammation, and metabolism. Three subtypes of PPARs are known: PPAR-alpha (PPARα), PPAR-gamma (PPARγ), and PPAR-beta/delta (PPARβ/δ). PPARα activation reduces lipid levels and regulates energy homeostasis, activation of PPARγ results in regulation of adipogenesis, and PPARβ/δ activation increases fatty acid metabolism and lipolysis. PPARs are linked to various diseases, including but not limited to diabetes, non-alcoholic fatty liver disease, glaucoma and atherosclerosis. In the past decade, numerous studies have assessed the functional properties of PPARs in the eye and key PPAR mechanisms have been discovered, particularly regarding the retina and cornea. PPARγ and PPARα are well established in their functions in ocular homeostasis regarding neuroprotection, neovascularization, and inflammation, whereas PPARβ/δ isoform function remains understudied. Naturally, studies on PPAR agonists and antagonists, associated with ocular pathology, have also gained traction with the development of PPAR synthetic ligands. Studies on PPARs has significantly influenced novel therapeutics for diabetic eye disease, ocular neuropathy, dry eye, and age-related macular degeneration (AMD). In this review, therapeutic potentials and implications will be highlighted, as well as reported adverse effects. Further investigations are necessary before any of the PPARs ligands can be utilized, in the clinics, to treat eye diseases. Future research on the prominent role of PPARs will help unravel the complex mechanisms involved in order to prevent and treat ocular diseases.
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Affiliation(s)
- Paulina Escandon
- North Texas Eye Research Institute, University of North Texas Health Science Center, 3500 Camp Bowie Blvd, Fort Worth, TX, 76107, USA; Department of Pharmaceutical Sciences, University of North Texas Health Science Center, 3500 Camp Bowie Blvd, Fort Worth, TX, 76107, USA
| | - Brenda Vasini
- North Texas Eye Research Institute, University of North Texas Health Science Center, 3500 Camp Bowie Blvd, Fort Worth, TX, 76107, USA; Department of Pharmaceutical Sciences, University of North Texas Health Science Center, 3500 Camp Bowie Blvd, Fort Worth, TX, 76107, USA
| | - Amy E Whelchel
- Department of Physiology, University of Oklahoma Health Sciences Center, 940 Stanton L Young, Oklahoma City, OK, USA
| | - Sarah E Nicholas
- North Texas Eye Research Institute, University of North Texas Health Science Center, 3500 Camp Bowie Blvd, Fort Worth, TX, 76107, USA; Department of Pharmaceutical Sciences, University of North Texas Health Science Center, 3500 Camp Bowie Blvd, Fort Worth, TX, 76107, USA
| | - H Greg Matlock
- Department of Physiology, University of Oklahoma Health Sciences Center, 940 Stanton L Young, Oklahoma City, OK, USA
| | - Jian-Xing Ma
- Department of Physiology, University of Oklahoma Health Sciences Center, 940 Stanton L Young, Oklahoma City, OK, USA; Harold Hamm Oklahoma Diabetes Center, 1000 N Lincoln Blvd, Oklahoma City, OK, USA
| | - Dimitrios Karamichos
- North Texas Eye Research Institute, University of North Texas Health Science Center, 3500 Camp Bowie Blvd, Fort Worth, TX, 76107, USA; Department of Pharmaceutical Sciences, University of North Texas Health Science Center, 3500 Camp Bowie Blvd, Fort Worth, TX, 76107, USA; Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, 3500 Camp Bowie Blvd, Fort Worth, TX, 76107, USA.
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21
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Barras A, Sauvage F, de Hoon I, Braeckmans K, Hua D, Buvat G, Fraire JC, Lethien C, Sebag J, Harrington M, Abderrahmani A, Boukherroub R, De Smedt S, Szunerits S. Carbon quantum dots as a dual platform for the inhibition and light-based destruction of collagen fibers: implications for the treatment of eye floaters. NANOSCALE HORIZONS 2021; 6:449-461. [PMID: 33903870 DOI: 10.1039/d1nh00157d] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Common in myopia and aging, vitreous opacities arise from clumped collagen fibers within the vitreous body that cast shadows on the retina, appearing as 'floaters' to the patient. Vitreous opacities degrade contrast sensitivity function and can cause significant impairment in vision-related quality-of-life, representing an unmet and underestimated medical need. One therapeutic approach could be the use of versatile light-responsive nanostructures which (i) interfere with the formation of collagen fibers and/or (ii) destroy aggregates of vitreous collagen upon pulsed-laser irradiation at low fluences. In this work, the potential of positively and negatively charged carbon quantum dots (CQDs) to interfere with the aggregation of type I collagen is investigated. We demonstrate that fibrillation of collagen I is prevented most strongly by positively charged CQDs (CQDs-2) and that pulsed-laser illumination allowed to destroy type I collagen aggregates and vitreous opacities (as obtained from patients after vitrectomy) treated with CQDs-2.
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Affiliation(s)
- Alexandre Barras
- Univ. Lille, CNRS, Centrale Lille, Univ. Polytechnique Hauts-de-France, UMR 8520 - IEMN, F-59000 Lille, France.
| | - Félix Sauvage
- Laboratory of General Biochemistry and Physical Pharmacy, Faculty of Pharmaceutical Sciences, Ghent University, 9000 Ghent, Belgium.
| | - Inès de Hoon
- Univ. Lille, CNRS, Centrale Lille, Univ. Polytechnique Hauts-de-France, UMR 8520 - IEMN, F-59000 Lille, France. and Laboratory of General Biochemistry and Physical Pharmacy, Faculty of Pharmaceutical Sciences, Ghent University, 9000 Ghent, Belgium.
| | - Kevin Braeckmans
- Laboratory of General Biochemistry and Physical Pharmacy, Faculty of Pharmaceutical Sciences, Ghent University, 9000 Ghent, Belgium.
| | - Dawei Hua
- Laboratory of General Biochemistry and Physical Pharmacy, Faculty of Pharmaceutical Sciences, Ghent University, 9000 Ghent, Belgium.
| | - Gaëtan Buvat
- Univ. Lille, CNRS, Centrale Lille, Univ. Polytechnique Hauts-de-France, UMR 8520 - IEMN, F-59000 Lille, France.
| | - Juan C Fraire
- Laboratory of General Biochemistry and Physical Pharmacy, Faculty of Pharmaceutical Sciences, Ghent University, 9000 Ghent, Belgium.
| | - Christophe Lethien
- Univ. Lille, CNRS, Centrale Lille, Univ. Polytechnique Hauts-de-France, UMR 8520 - IEMN, F-59000 Lille, France.
| | - J Sebag
- VMR Institute for Vitreous Macula Retina, Huntington Beach, California 92647, USA and Doheny Eye Institute/UCLA, Los Angeles, California 90033, USA
| | | | - Amar Abderrahmani
- Univ. Lille, CNRS, Centrale Lille, Univ. Polytechnique Hauts-de-France, UMR 8520 - IEMN, F-59000 Lille, France.
| | - Rabah Boukherroub
- Univ. Lille, CNRS, Centrale Lille, Univ. Polytechnique Hauts-de-France, UMR 8520 - IEMN, F-59000 Lille, France.
| | - Stefaan De Smedt
- Laboratory of General Biochemistry and Physical Pharmacy, Faculty of Pharmaceutical Sciences, Ghent University, 9000 Ghent, Belgium.
| | - Sabine Szunerits
- Univ. Lille, CNRS, Centrale Lille, Univ. Polytechnique Hauts-de-France, UMR 8520 - IEMN, F-59000 Lille, France.
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22
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Okada M, Chiu D, Yeoh J. Vitreomacular disorders: a review of the classification, pathogenesis and treatment paradigms including new surgical techniques. Clin Exp Optom 2021; 104:672-683. [PMID: 33899681 DOI: 10.1080/08164622.2021.1896946] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
This review explores how optical coherence tomography has guided our assessment of vitreomacular disorders. Vitreomacular disorders (VMD), such as macular holes and epiretinal membranes are common and potentially sight threatening. The introduction and widespread use of optical coherence tomography (OCT) imaging technology has transformed our ability to visualise the vitreoretinal interface. This review discusses the pathogenesis and updated classification scheme for VMD in the OCT era. Imaging biomarkers and the treatment algorithm, including the role of novel therapeutics, for managing patients with VMD are presented.
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Affiliation(s)
- Mali Okada
- Vitreoretinal Unit, Royal Victorian Eye and Ear Hospital, Melbourne, Australia
| | - Daniel Chiu
- Vitreoretinal Unit, Royal Victorian Eye and Ear Hospital, Melbourne, Australia
| | - Jonathan Yeoh
- Vitreoretinal Unit, Royal Victorian Eye and Ear Hospital, Melbourne, Australia
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23
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Experimental assessment of the performance of vitreous cutters with fluids with different rheological properties. Graefes Arch Clin Exp Ophthalmol 2021; 259:1113-1121. [PMID: 33394160 DOI: 10.1007/s00417-020-05061-4] [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: 10/02/2020] [Revised: 12/02/2020] [Accepted: 12/21/2020] [Indexed: 10/22/2022] Open
Abstract
PURPOSE To assess the influence of rheological properties of an artificial vitreous (AV) on the performance of double-blade (DB) and single-blade (SB) guillotine vitreous cutters, with 23-, 25-, and 27-gauge (G) probes. METHODS We evaluate the aspiration flow rate, using an optical method, based on image processing. Experiments are conducted using ten viscoelastic vitreous phantoms, with different properties that are measured with rheological tests. RESULTS Aspiration rate strongly varies with fluid properties. Regardless of cutter geometry and operational conditions, the flow rate significantly decreases as vitreous viscosity and elasticity increase. CONCLUSIONS All tested vitreous probes are very sensitive to changes in fluid rheology. SB cutters produce smaller flow rates compared with DB ones of the same caliber; however, they are less sensitive to fluid properties at low aspiration pressures. The use of vitreous substitutes for test performance guarantees comparability between flow rate results achieved with different vitrectomy systems operating in different media. This outcome is further confirmed by the low values of estimated flow rate relative errors.
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Shigueoka LS, Mariottoni EB, Thompson AC, Jammal AA, Costa VP, Medeiros FA. Predicting Age From Optical Coherence Tomography Scans With Deep Learning. Transl Vis Sci Technol 2021; 10:12. [PMID: 33510951 PMCID: PMC7804495 DOI: 10.1167/tvst.10.1.12] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2020] [Accepted: 11/09/2020] [Indexed: 01/17/2023] Open
Abstract
Purpose To assess whether age can be predicted from deep learning analysis of peripapillary spectral-domain optical coherence tomography (SD-OCT) B-scans and to determine the importance of specific retinal areas on the predictions. Methods Deep learning (DL) convolutional neural networks were developed to predict chronological age in healthy subjects using peripapillary SD-OCT B-scan images. Models were built using the whole B-scan, as well as using specific regions through image ablation. Cross-validation was used for training and testing the model. Mean absolute error (MAE) and correlations between predicted and observed age were used to evaluate model performance. Results A total of 7271 images from 542 eyes of 278 healthy subjects were included. DL predictions of age using the whole B-scan were strongly correlated with chronological age (MAE = 5.82 years; r = 0.860, P < 0.001). The model also accurately discriminated between the lowest and highest tertiles of age, with an area under the receiver operating characteristic curve of 0.962. In general, class activation maps tended to show a diffuse pattern of activation throughout the scan image. For specific structures of the B-scan, the layers with the strongest correlations with chronological age were the choroid and vitreous (both r = 0.736), whereas retinal nerve fiber layer had the lowest correlation (r = 0.492). Conclusions A DL algorithm was able to accurately predict age from whole peripapillary SD-OCT B-scans. Translational Relevance DL models applied to SD-OCT scans suggest that aging appears to affect several layers in the posterior eye segment.
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Affiliation(s)
- Leonardo S. Shigueoka
- Vision, Imaging and Performance Laboratory (VIP), Duke Eye Center and Department of Ophthalmology, Duke University, Durham, NC, USA
- Glaucoma Service, Department of Ophthalmology, University of Campinas, Campinas, São Paulo, Brazil
| | - Eduardo B. Mariottoni
- Vision, Imaging and Performance Laboratory (VIP), Duke Eye Center and Department of Ophthalmology, Duke University, Durham, NC, USA
| | - Atalie C. Thompson
- Vision, Imaging and Performance Laboratory (VIP), Duke Eye Center and Department of Ophthalmology, Duke University, Durham, NC, USA
| | - Alessandro A. Jammal
- Vision, Imaging and Performance Laboratory (VIP), Duke Eye Center and Department of Ophthalmology, Duke University, Durham, NC, USA
- Glaucoma Service, Department of Ophthalmology, University of Campinas, Campinas, São Paulo, Brazil
| | - Vital P. Costa
- Glaucoma Service, Department of Ophthalmology, University of Campinas, Campinas, São Paulo, Brazil
| | - Felipe A. Medeiros
- Vision, Imaging and Performance Laboratory (VIP), Duke Eye Center and Department of Ophthalmology, Duke University, Durham, NC, USA
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Tram NK, Maxwell CJ, Swindle-Reilly KE. Macro- and Microscale Properties of the Vitreous Humor to Inform Substitute Design and Intravitreal Biotransport. Curr Eye Res 2020; 46:429-444. [PMID: 33040616 DOI: 10.1080/02713683.2020.1826977] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Research on the vitreous humor and development of hydrogel vitreous substitutes have gained a rapid increase in interest within the past two decades. However, the properties of the vitreous humor and vitreous substitutes have yet to be consolidated. In this paper, the mechanical properties of the vitreous humor and hydrogel vitreous substitutes were systematically reviewed. The number of publications on the vitreous humor and vitreous substitutes over the years, as well as their respective testing conditions and testing techniques were analyzed. The mechanical properties of the human vitreous were found to be most similar to the vitreous of pigs and rabbits. The storage and loss moduli of the hydrogel vitreous substitutes developed were found to be orders of magnitude higher in comparison to the native human vitreous. However, the reported modulus for human vitreous, which was most commonly tested in vitro, has been hypothesized to be different in vivo. Future studies should focus on testing the mechanical properties of the vitreous in situ or in vivo. In addition to its mechanical properties, the vitreous humor has other biotransport mechanisms and biochemical functions that establish a redox balance and maintain an oxygen gradient inside the vitreous chamber to protect intraocular tissues from oxidative damage. Biomimetic hydrogel vitreous substitutes have the potential to provide ophthalmologists with additional avenues for treating and controlling vitreoretinal diseases while preventing complications after vitrectomy. Due to the proximity and interconnectedness of the vitreous humor to other ocular tissues, particularly the lens and the retina, more interest has been placed on understanding the properties of the vitreous humor in recent years. A better understanding of the properties of the vitreous humor will aid in improving the design of biomimetic vitreous substitutes and enhancing intravitreal biotransport.
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Affiliation(s)
- Nguyen K Tram
- Department of Biomedical Engineering, The Ohio State University, Columbus, OH, USA
| | - Courtney J Maxwell
- Department of Biomedical Engineering, The Ohio State University, Columbus, OH, USA
| | - Katelyn E Swindle-Reilly
- Department of Biomedical Engineering, The Ohio State University, Columbus, OH, USA.,William G. Lowrie Department of Chemical and Biomolecular Engineering, The Ohio State University, Columbus, OH, USA.,Department of Ophthalmology & Visual Science, The Ohio State University, Columbus, OH, USA
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Gabriel RS, Boisvert CJ, Mehta MC. Review of Vitreopapillary Traction Syndrome. Neuroophthalmology 2020; 44:213-218. [PMID: 33012906 DOI: 10.1080/01658107.2020.1725063] [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: 10/24/2022] Open
Abstract
Vitreopapillary traction (VPT) syndrome is a potentially visually significant disorder of the vitreopapillary interface characterised by an incomplete posterior vitreous detachment with the persistently adherent vitreous exerting tractional pull on the optic disc and resulting in morphologic alterations and a consequent decline of visual function. It is most commonly unilateral but bilateral reports have also been described. The cause of the condition may be unknown or idiopathic, although the histology of traction shows proliferation of fibrous astrocytes, myofibroblasts, fibrocytes, and retinal pigment epithelial cells. It is theorised that VPT may induce a congested optic disc with neuronal dysfunction as well as decreased prelaminar flow. The present study reviews and summarises the features, diagnosis, and management of VPT.
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Affiliation(s)
- Rami S Gabriel
- School of Medicine, University of California, Irvine, California, USA
| | - Chantal J Boisvert
- Department of Ophthalmology, Duke Eye Center and Duke University Medical Center, Durham, North Carolina, USA
| | - Mitul C Mehta
- Gavin Herbert Eye Institute, University of California, Irvine, California, USA
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Rangchian A, Hubschman JP, Kavehpour HP. Time dependent degradation of vitreous gel under enzymatic reaction: Polymeric network role in fluid properties. J Biomech 2020; 109:109921. [DOI: 10.1016/j.jbiomech.2020.109921] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Revised: 06/24/2020] [Accepted: 06/25/2020] [Indexed: 02/06/2023]
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Sebag J. Vitreous and Vision Degrading Myodesopsia. Prog Retin Eye Res 2020; 79:100847. [PMID: 32151758 DOI: 10.1016/j.preteyeres.2020.100847] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2019] [Revised: 03/01/2020] [Accepted: 03/03/2020] [Indexed: 12/16/2022]
Abstract
Macromolecules comprise only 2% of vitreous, yet are responsible for its gel state, transparency, and physiologic function(s) within the eye. Myopia and aging alter collagen and hyaluronan association causing concurrent gel liquefaction and fibrous degeneration. The resulting vitreous opacities and collapse of the vitreous body during posterior vitreous detachment are the most common causes for the visual phenomenon of vitreous floaters. Previously considered innocuous, the vitreous opacities that cause floaters sometimes impact vision by profoundly degrading contrast sensitivity function and impairing quality-of-life. While many people adapt to vitreous floaters, clinically significant cases can be diagnosed with Vision Degrading Myodesopsia based upon echographic assessment of vitreous structure and by measuring contrast sensitivity function. Perhaps due to the ubiquity of floaters, the medical profession has to date largely ignored the plight of those with Vision Degrading Myodesopsia. Improved diagnostics will enable better disease staging and more accurate identification of severe cases that merit therapy. YAG laser treatments may occasionally be slightly effective, but vitrectomy is currently the definitive cure. Future developments will usher in more informative diagnostic approaches as well as safer and more effective therapeutic strategies. Improved laser treatments, new pharmacotherapies, and possibly non-invasive optical corrections are exciting new approaches to pursue. Ultimately, enhanced understanding of the underlying pathogenesis of Vision Degrading Myodesopsia should result in prevention, the ultimate goal of modern Medicine.
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Affiliation(s)
- J Sebag
- VMR Institute for Vitreous Macula Retina, Huntington Beach, CA, USA; Doheny Eye Institute, Pasadena, CA, USA; Department of Ophthalmology, Geffen School of Medicine, University of California, Los Angeles, CA, USA.
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Ankamah E, Sebag J, Ng E, Nolan JM. Vitreous Antioxidants, Degeneration, and Vitreo-Retinopathy: Exploring the Links. Antioxidants (Basel) 2019; 9:antiox9010007. [PMID: 31861871 PMCID: PMC7022282 DOI: 10.3390/antiox9010007] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Revised: 12/05/2019] [Accepted: 12/16/2019] [Indexed: 02/06/2023] Open
Abstract
The transparent vitreous body, which occupies about 80% of the eye’s volume, is laden with numerous enzymatic and non-enzymatic antioxidants that could protect the eye from oxidative stress and disease. Aging is associated with degeneration of vitreous structure as well as a reduction in its antioxidant capacity. A growing body of evidence suggests these age-related changes may be the precursor of numerous oxidative stress-induced vitreo-retinopathies, including vision degrading myodesopsia, the clinically significant entoptic phenomena that can result from advanced vitreous degeneration. Adequate intravitreal antioxidant levels may be protective against vitreous degeneration, possibly preventing and even improving vision degrading myodesopsia as well as mitigating various other vitreo-retinopathies. The present article is, therefore, a review of the different antioxidant molecules within vitreous and the inter-relationships between vitreous antioxidant capacity and degeneration.
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Affiliation(s)
- Emmanuel Ankamah
- Nutrition Research Centre Ireland, School of Health Science, Carriganore House, Waterford Institute of Technology, West Campus, Co., X91 K236 Waterford, Ireland;
- Institute of Eye Surgery, UPMC Whitfield, Buttlerstown, Co., X91 DH9W Waterford, Ireland
- Correspondence: (E.A.); (J.M.N.)
| | - J. Sebag
- VMR Consulting Inc., Huntington Beach, CA 92647, USA;
| | - Eugene Ng
- Nutrition Research Centre Ireland, School of Health Science, Carriganore House, Waterford Institute of Technology, West Campus, Co., X91 K236 Waterford, Ireland;
- Institute of Eye Surgery, UPMC Whitfield, Buttlerstown, Co., X91 DH9W Waterford, Ireland
| | - John M. Nolan
- Nutrition Research Centre Ireland, School of Health Science, Carriganore House, Waterford Institute of Technology, West Campus, Co., X91 K236 Waterford, Ireland;
- Correspondence: (E.A.); (J.M.N.)
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Tram NK, Jiang P, Torres‐Flores TC, Jacobs KM, Chandler HL, Swindle‐Reilly KE. A Hydrogel Vitreous Substitute that Releases Antioxidant. Macromol Biosci 2019; 20:e1900305. [DOI: 10.1002/mabi.201900305] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Revised: 11/11/2019] [Indexed: 02/05/2023]
Affiliation(s)
- Nguyen K. Tram
- Department of Biomedical Engineering The Ohio State University 1080 Carmack Rd. Columbus OH 43210 USA
| | - Pengfei Jiang
- William G. Lowrie Department of Chemical and Biomolecular Engineering The Ohio State University 151 W. Woodruff Avenue Columbus OH 43210 USA
| | - Tiara C. Torres‐Flores
- Department of Biomedical Engineering The Ohio State University 1080 Carmack Rd. Columbus OH 43210 USA
| | - Kane M. Jacobs
- William G. Lowrie Department of Chemical and Biomolecular Engineering The Ohio State University 151 W. Woodruff Avenue Columbus OH 43210 USA
| | - Heather L. Chandler
- College of Optometry The Ohio State University 338 West 10th Avenue Columbus OH 43210 USA
| | - Katelyn E. Swindle‐Reilly
- Department of Biomedical Engineering The Ohio State University 1080 Carmack Rd. Columbus OH 43210 USA
- William G. Lowrie Department of Chemical and Biomolecular Engineering The Ohio State University 151 W. Woodruff Avenue Columbus OH 43210 USA
- Department of Ophthalmology and Visual Science The Ohio State University 915 Olentangy River Road, Suite 5000 Columbus OH 43212 USA
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Coussa RG, Antaki F, Zaguia F, Vila N, Kapusta MA. Prognostic factors of postoperative intraretinal cystoid spaces after primary pars plana vitrectomy for vitreomacular traction. J Curr Ophthalmol 2019; 31:399-405. [PMID: 31844790 PMCID: PMC6896453 DOI: 10.1016/j.joco.2019.05.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Revised: 05/17/2019] [Accepted: 05/31/2019] [Indexed: 11/18/2022] Open
Abstract
Purpose To study the anatomical and surgical prognostic factors related to developing postoperative intraretinal cystoid spaces (ICS) six months after 25-gauge pars plana vitrectomy (PPV) for vitreomacular traction (VMT). Methods The study is a retrospective case series of patients presenting with VMT treated primarily with PPV. All patients underwent 25-gauge PPV by the same retina surgeon. Intra-operative parameters were all recorded. Postoperative visual acuity (VA), foveal thickness, and ICS were collected over six months of follow-up. ICS were defined as hyporeflective cysts divided by hyperreflective septa on optical coherence tomography (OCT). Patients with ICS persistence 3 months postoperatively received topical treatment extension. The primary outcome measure was odds of preoperative ICS in patients with postoperative ICS compared to controls. Secondary outcome measures were odds of presence of an attached hyaloid to the optic disc, presence of pseudophakia, the use of intra-operative air, and the use of more than one intra-operative indocyanine green (ICG) injections in patients with postoperative ICS compared to controls. Results Two hundred and eighty treatment-naïve patients with preoperative diagnosis of epiretinal membrane (ERM) were reviewed. Thirty patients with VMT, confirmed both preoperatively on OCT and intra-operatively, were included. Postoperatively, 40% (n = 12) presented with ICS at 6 months. Among these, 83% (n = 10) had ICS prior to PPV. Patients presenting with preoperative ICS were significantly more at risk of having persistent ICS postoperatively (P < 0.05). The following factors did not statistically affect ICS occurrence: optic disc hyaloid attachment status, phakia/pseudophakia, intra-operative air vs. sulfur hexafluoride (SF6), and the number of intra-operative ICG injections. Conclusions Our data demonstrate a predictive relationship between the occurrence/persistence of ICS post-PPV for VMT and the initial foveal status. Specifically, having preoperative ICS is a major risk factor for its persistence postoperatively. Our data highlight the pathophysiological importance of the vitreous phase and its effect on visual prognosis.
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Affiliation(s)
- Razek Georges Coussa
- Department of Ophthalmology, Jewish General Hospital, McGill University Health Center, Montreal, Canada
- Cole Eye Institute, Cleveland Clinic, Cleveland, OH, USA
- Corresponding author. Cole Eye Institute, Cleveland Clinic Main Campus, 9500 Euclid Avenue, Cleveland, OH, 44195, USA.
| | - Fares Antaki
- Department of Ophthalmology, Jewish General Hospital, McGill University Health Center, Montreal, Canada
- Department of Ophthalmology, Université de Montréal, Montreal, Canada
| | - Fatma Zaguia
- Department of Ophthalmology, Jewish General Hospital, McGill University Health Center, Montreal, Canada
| | - Natalia Vila
- Department of Ophthalmology, Jewish General Hospital, McGill University Health Center, Montreal, Canada
| | - Michael Alton Kapusta
- Department of Ophthalmology, Jewish General Hospital, McGill University Health Center, Montreal, Canada
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Liu Z, Liow SS, Lai SL, Alli-Shaik A, Holder GE, Parikh BH, Krishnakumar S, Li Z, Tan MJ, Gunaratne J, Barathi VA, Hunziker W, Lakshminarayanan R, Tan CWT, Chee CK, Zhao P, Lingam G, Loh XJ, Su X. Retinal-detachment repair and vitreous-like-body reformation via a thermogelling polymer endotamponade. Nat Biomed Eng 2019; 3:598-610. [DOI: 10.1038/s41551-019-0382-7] [Citation(s) in RCA: 63] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Accepted: 03/05/2019] [Indexed: 12/31/2022]
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Nawaz IM, Rezzola S, Cancarini A, Russo A, Costagliola C, Semeraro F, Presta M. Human vitreous in proliferative diabetic retinopathy: Characterization and translational implications. Prog Retin Eye Res 2019; 72:100756. [PMID: 30951889 DOI: 10.1016/j.preteyeres.2019.03.002] [Citation(s) in RCA: 77] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Revised: 03/26/2019] [Accepted: 03/28/2019] [Indexed: 02/07/2023]
Abstract
Diabetic retinopathy (DR) is one of the leading causes of visual impairment in the working-age population. DR is a progressive eye disease caused by long-term accumulation of hyperglycaemia-mediated pathological alterations in the retina of diabetic patients. DR begins with asymptomatic retinal abnormalities and may progress to advanced-stage proliferative diabetic retinopathy (PDR), characterized by neovascularization or preretinal/vitreous haemorrhages. The vitreous, a transparent gel that fills the posterior cavity of the eye, plays a vital role in maintaining ocular function. Structural and molecular alterations of the vitreous, observed during DR progression, are consequences of metabolic and functional modifications of the retinal tissue. Thus, vitreal alterations reflect the pathological events occurring at the vitreoretinal interface. These events are caused by hypoxic, oxidative, inflammatory, neurodegenerative, and leukostatic conditions that occur during diabetes. Conversely, PDR vitreous can exert pathological effects on the diabetic retina, resulting in activation of a vicious cycle that contributes to disease progression. In this review, we recapitulate the major pathological features of DR/PDR, and focus on the structural and molecular changes that characterize the vitreal structure and composition during DR and progression to PDR. In PDR, vitreous represents a reservoir of pathological signalling molecules. Therefore, in this review we discuss how studying the biological activity of the vitreous in different in vitro, ex vivo, and in vivo experimental models can provide insights into the pathogenesis of PDR. In addition, the vitreous from PDR patients can represent a novel tool to obtain preclinical experimental evidences for the development and characterization of new therapeutic drug candidates for PDR therapy.
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Affiliation(s)
- Imtiaz M Nawaz
- Department of Molecular and Translational Medicine, University of Brescia, Italy
| | - Sara Rezzola
- Department of Molecular and Translational Medicine, University of Brescia, Italy
| | - Anna Cancarini
- Department of Ophthalmology, University of Brescia, Italy
| | - Andrea Russo
- Department of Ophthalmology, University of Brescia, Italy
| | - Ciro Costagliola
- Department of Medicine and Health Sciences, University of Molise, Campobasso, Italy
| | | | - Marco Presta
- Department of Molecular and Translational Medicine, University of Brescia, Italy.
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Tram NK, Swindle-Reilly KE. Rheological Properties and Age-Related Changes of the Human Vitreous Humor. Front Bioeng Biotechnol 2018; 6:199. [PMID: 30619846 PMCID: PMC6305337 DOI: 10.3389/fbioe.2018.00199] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Accepted: 12/04/2018] [Indexed: 02/03/2023] Open
Abstract
The vitreous humor is a fragile, transparent hydrogel situated between the lens and the retina, occupying 80% of the eye's volume. Due to its viscoelastic behavior, the vitreous serves as a mechanical damper for the eye, absorbing impacts, and protecting the lens and retina. The vitreous liquefies with age, which compromises its function as a shock absorber and causes complications including retinal detachment, macular holes, and vitreous hemorrhage. Studies on the viscoelastic properties of the vitreous have been limited. Rheological testing of the vitreous has commonly been done on non-primate mammalian species. Human vitreous rheological properties have been previously reported; however, various measurement techniques were used, resulting in data that differed by orders of magnitude. Shear rheometry is commonly used to characterize soft tissues and hydrogels such as the vitreous humor. However, no human vitreous rheological data have been reported using this technique, preventing direct comparison to other published work. Additionally, no age-related changes in the mechanical properties of the human vitreous humor have been reported. Human vitreous samples (n = 39, aged 62 ± 15 years) were tested using a shear rheometer. Small amplitude oscillatory shear and creep experiments were performed. The linear viscoelastic region of the human vitreous was found to be below 1% strain. The solid phase of the old human vitreous was found to be stiffer than the young human vitreous and the porcine vitreous. The stiffness of the human vitreous gel also appeared to be positively correlated with age. Vitreous dehydration due to a decrease in hyaluronic acid concentration with age was proposed to cause the stiffening of the solid phase of the vitreous gel. Vitreous liquefaction, therefore, might be characterized as a simultaneous increase in liquid volume and localized stiffening of the vitreous gel. The phase separation of the vitreous humor with age has been hypothesized as the cause of many vitreous-related complications. This study provides viscoelastic properties and age-related changes of the human vitreous humor, which will aid in the design of biomimetic vitreous substitutes, enhancement in analyzing intravitreal transport of therapeutics, and understanding the pathological conditions of the vitreous humor.
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Affiliation(s)
- Nguyen K Tram
- Department of Biomedical Engineering, The Ohio State University, Columbus, OH, United States
| | - Katelyn E Swindle-Reilly
- Department of Biomedical Engineering, The Ohio State University, Columbus, OH, United States.,William G. Lowrie Department of Chemical and Biomolecular Engineering, The Ohio State University, Columbus, OH, United States.,Department of Ophthalmology and Visual Science, The Ohio State University, Columbus, OH, United States
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7.1 T MRI and T2 mapping of the human and porcine vitreous body post mortem. Eur J Pharm Biopharm 2018; 131:82-91. [DOI: 10.1016/j.ejpb.2018.07.021] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2018] [Revised: 07/24/2018] [Accepted: 07/25/2018] [Indexed: 12/30/2022]
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Huang D, Chen YS, Xu Q, Hanes J, Rupenthal ID. Effects of enzymatic degradation on dynamic mechanical properties of the vitreous and intravitreal nanoparticle mobility. Eur J Pharm Sci 2018; 118:124-133. [DOI: 10.1016/j.ejps.2018.03.023] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Revised: 03/19/2018] [Accepted: 03/20/2018] [Indexed: 11/15/2022]
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Influence of the test method on in vitro drug release from intravitreal model implants containing dexamethasone or fluorescein sodium in poly (d,l-lactide-co-glycolide) or polycaprolactone. Eur J Pharm Biopharm 2018; 127:270-278. [PMID: 29490233 DOI: 10.1016/j.ejpb.2018.02.034] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2017] [Revised: 02/20/2018] [Accepted: 02/23/2018] [Indexed: 11/20/2022]
Abstract
Sustained intravitreal dexamethasone (DX) administration with the FDA and EMA approved Ozurdex® implant is indicated for the treatment of macular edema and non-infectious uveitis. Since drug release after intravitreal application cannot be determined in vivo in human eyes, the characterization of drug release in vitro in addition to animal models is of great importance. The aim of this study was to provide information about the influence of the test method on the in vitro drug release from intravitreal model implants. The following test methods were used: a shaking incubator experiment in reagent tubes, the small volume USP apparatus 7, the Vitreous Model (VM) and a system simulating the impact of movement on the VM (Eye Movement System, EyeMoS). Cylindrical model implants composed of DX and PLGA (poly (d,l-lactide-co-glycolide)) and additional polycaprolactone (PCL) implants containing fluorescein sodium (FS) as a model substance were produced by hot melt extrusion and were cut to a length of approximately 6 mm. Drug release was studied in ringer buffer pH 7.4 and in a modified polyacrylamide gel (PAAG) as vitreous substitute. In combination with the VM, the shape, the gel structure and a partial liquefaction (50%) were simulated in vitro. Swelling, disintegration, fragmentation, surface enlargement and changes in shape of the PLGA model implants were observed during the drug release study. We experienced that not each of the test methods and media were suitable for drug release studies of the PLGA implants. Marked differences in the release profiles were observed depending on the employed test method. These results emphasize the necessity to understand the underlying in vivo processes and to transfer the knowledge about the release determining factors into reliable in vitro test systems.
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Stein S, Bogdahn M, Rosenbaum C, Weitschies W, Seidlitz A. Distribution of fluorescein sodium and triamcinolone acetonide in the simulated liquefied and vitrectomized Vitreous Model with simulated eye movements. Eur J Pharm Sci 2017; 109:233-243. [PMID: 28823853 DOI: 10.1016/j.ejps.2017.08.018] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2017] [Revised: 07/26/2017] [Accepted: 08/17/2017] [Indexed: 01/20/2023]
Abstract
Intravitreal administration is the method of choice for drug delivery to the posterior segment of the eye with special emphasis on the vitreous body and its surrounding retinal vasculature. In order to gain a better understanding of the underlying distribution processes, an in vitro model simulating the vitreous body (Vitreous Model, VM) and a system simulating the impact of movement on the VM (Eye Movement System, EyeMoS) was previously developed. In the study reported here, these systems were modified in regard to a standardized injection procedure, the diversity of simulated eye movements, extended periods of investigation, the opportunity to simulate the state after vitrectomy and in considering the physiological temperature. Fluorescein sodium (FS) and triamcinolone acetonide (TA) were used as (model) drugs to examine the drug distribution within the VM. Vitrectomy was simulated by replacing half the volume of the polyacrylamide gel that was used as vitreous substitute with the clinically used Siluron® 5000 whereas for a simulated liquefaction half the volume of the gel was replaced by buffer. A simulated liquefaction caused a 12-fold faster distribution of FS compared to the simulated juvenile VM, which was most likely caused by convective forces and mass transfer. Also, the injection technique (injection into the gel or into the buffer compartment) influenced the resulting distribution pattern. Without any liquefaction, the previously described initial injection channel occurred with both (model) drugs and, in the case of TA, remained almost unchanged during the investigation period of 72h. Simulating vitrectomized eyes, TA did not spread uniformly, but either remained in the depot or strongly sedimented within the VM suggesting that a homogenous distribution of a TA suspension is highly unlikely in vitrectomized eyes. High variabilities were observed with ex vivo animal eyes, demonstrating the limited benefit of explanted tissues for such distribution studies. The combination of the modified VM and EyeMoS seems a valuable tool for characterizing intravitreal dosage forms in a reproducible simulation of diversified eye movements and a partially liquefied or vitrectomized vitreous body.
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Affiliation(s)
- Sandra Stein
- Institute of Pharmacy, Centre of Drug Absorption and Transport, Biopharmaceutics and Pharmaceutical Technology, University of Greifswald, Germany
| | - Malte Bogdahn
- Institute of Pharmacy, Centre of Drug Absorption and Transport, Biopharmaceutics and Pharmaceutical Technology, University of Greifswald, Germany
| | - Christoph Rosenbaum
- Institute of Pharmacy, Centre of Drug Absorption and Transport, Biopharmaceutics and Pharmaceutical Technology, University of Greifswald, Germany
| | - Werner Weitschies
- Institute of Pharmacy, Centre of Drug Absorption and Transport, Biopharmaceutics and Pharmaceutical Technology, University of Greifswald, Germany
| | - Anne Seidlitz
- Institute of Pharmacy, Centre of Drug Absorption and Transport, Biopharmaceutics and Pharmaceutical Technology, University of Greifswald, Germany.
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Liang J, Struckhoff JJ, Du H, Hamilton PD, Ravi N. Synthesis and characterization of in situ forming anionic hydrogel as vitreous substitutes. J Biomed Mater Res B Appl Biomater 2017; 105:977-988. [PMID: 26873608 PMCID: PMC5654599 DOI: 10.1002/jbm.b.33632] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2015] [Revised: 12/14/2015] [Accepted: 01/16/2016] [Indexed: 02/06/2023]
Abstract
The natural vitreous is a biological hydrogel consisting primarily of a collagen and anionic hyaluronate. It is surgically removed in many ocular diseases and replaced with fluids, gases, or silicone oils. We have been interested in developing synthetic hydrogels as vitreous substitutes. In this study, we combined the stiffness and hydrophobicity of polymethacrylamide (PMAM) and the anionic nature of polymethacrylate (PMAA) to make copolymers that would mimic the natural vitreous. We used bis-methacryloyl cystamine (BMAC) to introduce thiol groups for reversible crosslink. The Mn of copolymers ranged from ∼100 k to ∼200 k Da (polydisperisty index of 1.47-2.63) and their composition as determined by titration, 1 H NMR and disulfide test were close to the feed ratio. The reactivities of monomers were as follows: MAM > MAA ∼ BMAC. Copolymers with higher MAA contents gelled faster, swelled more, and had higher storage modulus (1.5 to 100 Pa) comparable to that of the natural vitreous. We evaluated the biocompatibility of copolymers by electric cell-substrate impedance sensing (ECIS) using human retinal pigment epithelial cells, primary porcine retinal pigmented epithelial cells, human microvascular endothelial cells adult dermis, and a fibroblast line 3T3. The biocompatibility decreases as the content of BMAC increases. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 977-988, 2017.
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Affiliation(s)
- Jue Liang
- Department of Ophthalmology and Visual Sciences, WA University School of Medicine, Saint Louis, Missouri
| | - Jessica J Struckhoff
- Department of Ophthalmology and Visual Sciences, WA University School of Medicine, Saint Louis, Missouri
| | - Hongwei Du
- Department of Ophthalmology and Visual Sciences, WA University School of Medicine, Saint Louis, Missouri
| | - Paul D Hamilton
- Department of Ophthalmology and Visual Sciences, WA University School of Medicine, Saint Louis, Missouri
| | - Nathan Ravi
- Department of Ophthalmology and Visual Sciences, WA University School of Medicine, Saint Louis, Missouri
- Department of Energy, Environmental and Chemical Engineering, WA University in St. Louis, Saint Louis, Missouri
- Department of Research, Veterans Affairs Medical Center, Saint Louis, Missouri
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Cases O, Obry A, Ben-Yacoub S, Augustin S, Joseph A, Toutirais G, Simonutti M, Christ A, Cosette P, Kozyraki R. Impaired vitreous composition and retinal pigment epithelium function in the FoxG1::LRP2 myopic mice. Biochim Biophys Acta Mol Basis Dis 2017; 1863:1242-1254. [DOI: 10.1016/j.bbadis.2017.03.022] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Revised: 03/09/2017] [Accepted: 03/29/2017] [Indexed: 01/12/2023]
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Schnepf A, Yappert MC, Borchman D. Regional distribution of phospholipids in porcine vitreous humor. Exp Eye Res 2017; 160:116-125. [PMID: 28552385 DOI: 10.1016/j.exer.2017.05.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2017] [Revised: 04/27/2017] [Accepted: 05/18/2017] [Indexed: 01/08/2023]
Abstract
This project explores the regional phospholipid distribution in porcine vitreous humor, retina, and lens. Matrix-assisted laser desorption mass spectrometry has been used previously to image lipids, proteins, and other metabolites in retinas and lenses. However, the regional composition of phospholipids in vitreous humors is not known. To address this issue, we have applied this mass spectral method to explore the regional phospholipid distribution in porcine vitreous humor both ex-situ and in-vitro. To establish the possible source(s) of phospholipids in the vitreous humor, compositional studies of the lens and retina were also pursued. Due to the overall low levels of phospholipids in vitreous humor, it was necessary to optimize the experimental approaches for ex-situ and in-vitro studies. The sensitivity observed in the spectra of methanol extracts from the lens and retina was higher than that for methanol:chloroform extracts, but the compositional trends were the same. A fourfold improvement in sensitivity was observed in the analysis of vitreous humor extracts obtained with the Bligh and Dyer protocol relative to the other two extraction methods. For ex-situ studies, the 'stamp method' with para-nitroaniline as the matrix was chosen. Throughout the vitreous humor, phosphatidylcholines were the most abundant phospholipids. In-vitro results showed higher relative levels of phospholipids compared to the 'stamp' method. However, more details in the regional phospholipid distribution were provided by the ex-situ approach. Both in-vitro and ex-situ results indicated higher levels of phospholipids in the posterior vitreous region, followed by the anterior and central regions. The posterior region contained more unsaturated species whereas more saturated phospholipids were detected in the anterior region. The observed trends suggest that the phospholipids detected in the posterior vitreous humor migrate from the retina and associated vasculature while those present in the anterior regions are likely to derive from the lens. Not all species found in the lens were observed in the vitreous humor. For example, whereas cholesterol was present in lens extracts, it was not detected in the vitreous humor. Overall, the higher relative abundance of unsaturated species in the posterior vitreous humor and also present in the retina suggests that these species may be able to disrupt the water-collagen-hyaluronan network and contribute to vitreous liquefaction.
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Affiliation(s)
- Abigail Schnepf
- Department of Chemistry, University of Louisville, Louisville KY, USA
| | | | - Douglas Borchman
- Department of Ophthalmology and Visual Sciences, University of Louisville, Louisville KY, USA
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Davis JT, Hamilton PD, Ravi N. Poly(acrylamide co-acrylic acid) for use as an in situ gelling vitreous substitute. J BIOACT COMPAT POL 2017. [DOI: 10.1177/0883911516688482] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Our objective is to improve on our previous work developing thiol-containing water-soluble copolyacrylamides that form hydrogels in situ for use as vitreous substitutes. In this study, we evaluate the incorporation of acrylic acid by varying the feed ratio of acrylic acid monomer from 0 to 40 mol% in combination with acrylamide, and bis-acryloylcystamine as the reversible cross-linker. After polymerization, the formed copolymer hydrogels were reduced with dithiothreitol to cleave the disulfide cross-linkers. Purified, lyophilized copolymers were made in a concentration range of 12.5–17.5 mg/mL (polymer in deionized water) and were gelled by oxidation. Chemical, physical, optical, and rheological characterizations along with in vitro biocompatibility studies were performed using thiazolyl blue and Electric Cell–substrate Impedance Sensing. Increasing the percentage of acrylic acid caused the polymer to gel at 12.5 mg/mL as opposed to 20 mg/mL without acrylic acid. Storage modulus values covered the range of natural vitreous (1–108 Pa). Biocompatibility testing in tissue culture with retinal pigment epithelial cells (ARPE-19) showed no toxicity at 10 mg/mL or less when compared to controls, higher concentrations. In contrast to our previously reported copolyacrylamide hydrogels, these hydrogels remain optically clear and gel at lower concentrations and have the potential for use as vitreous substitutes.
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Affiliation(s)
- Joshua T Davis
- VA St. Louis Health Care System–John Cochran Division, St. Louis, MO, USA
- Department of Ophthalmology and Visual Science, Washington University in St. Louis, St. Louis, MO, USA
| | - Paul D Hamilton
- VA St. Louis Health Care System–John Cochran Division, St. Louis, MO, USA
- Department of Ophthalmology and Visual Science, Washington University in St. Louis, St. Louis, MO, USA
| | - Nathan Ravi
- VA St. Louis Health Care System–John Cochran Division, St. Louis, MO, USA
- Department of Ophthalmology and Visual Science, Washington University in St. Louis, St. Louis, MO, USA
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Fokkens BT, Mulder DJ, Schalkwijk CG, Scheijen JL, Smit AJ, Los LI. Vitreous advanced glycation endproducts and α-dicarbonyls in retinal detachment patients with type 2 diabetes mellitus and non-diabetic controls. PLoS One 2017; 12:e0173379. [PMID: 28264049 PMCID: PMC5338797 DOI: 10.1371/journal.pone.0173379] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2016] [Accepted: 02/20/2017] [Indexed: 01/14/2023] Open
Abstract
Purpose Advanced glycation endproducts (AGEs) and their precursors α-dicarbonyls are implicated in the progression of diabetic retinopathy. The purpose of this study was to assess AGEs and α-dicarbonyls in the vitreous of patients with type 2 diabetes mellitus (T2DM) with early stages or absence of diabetic retinopathy. Methods We examined vitreous samples obtained during vitrectomy from 31 T2DM patients presenting themselves with rhegmatogenous retinal detachment and compared these to 62 non-diabetic rhegmatogenous retinal detachment patients, matched on age, estimated glomerular filtration rate, smoking, intra-ocular lens implantation, and proliferative vitreoretinopathy. AGEs (pentosidine, Nε-(carboxymethyl)lysine, Nε-(carboxyethyl)lysine, and 5-hydro-5-methylimidazolone) and α-dicarbonyls (3-deoxyglucosone, methylglyoxal, and glyoxal) were measured by ultra performance liquid chromatography or high performance liquid chromatography. Skin autofluorescence was measured by the AGE Reader. Results Mean age was 64 ± 7.6 years for T2DM patients and 63 ± 8.1 years for controls. For T2DM patients, median diabetes duration was 2.2 (0.3–7.4) years. Non-proliferative diabetic retinopathy was present in 1 patient and classified as absent or background retinopathy in 30 patients. Vitreous levels of pentosidine (2.20 vs. 1.59 μmol/mol lysine, p = 0.012) and 3-deoxyglucosone (809 vs. 615 nmol/L, p = 0.001) were significantly elevated in T2DM patients compared to controls. Other AGEs and α-dicarbonyls in the vitreous were not significantly different. There was a trend for increased skin autofluorescence in T2DM patients as compared to controls (p = 0.07). Conclusions Pentosidine and 3-deoxyglucosone concentrations were increased in the vitreous of rhegmatogenous retinal detachment patients with a relatively short duration of diabetes compared to non-diabetic rhegmatogenous retinal detachment patients.
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Affiliation(s)
- Bernardina T. Fokkens
- Department of Internal Medicine, University of Groningen, University Medical Center Groningen (UMCG), Groningen, the Netherlands
- Research Institute GUIDE, Graduate School of Medical Sciences, University of Groningen, University Medical Center Groningen (UMCG), Groningen, the Netherlands
- Department of Ophthalmology, University of Groningen, University Medical Center Groningen (UMCG), the Netherlands
- * E-mail:
| | - Douwe J. Mulder
- Department of Internal Medicine, University of Groningen, University Medical Center Groningen (UMCG), Groningen, the Netherlands
| | - Casper G. Schalkwijk
- Laboratory for Metabolism and Vascular Medicine, Maastricht University, Department of Experimental Internal Medicine, Maastricht, the Netherlands
| | - Jean L. Scheijen
- Laboratory for Metabolism and Vascular Medicine, Maastricht University, Department of Experimental Internal Medicine, Maastricht, the Netherlands
| | - Andries J. Smit
- Department of Internal Medicine, University of Groningen, University Medical Center Groningen (UMCG), Groningen, the Netherlands
- Research Institute GUIDE, Graduate School of Medical Sciences, University of Groningen, University Medical Center Groningen (UMCG), Groningen, the Netherlands
| | - Leonoor I. Los
- Department of Ophthalmology, University of Groningen, University Medical Center Groningen (UMCG), the Netherlands
- W.J. Kolff Institute, Graduate School of Medical Sciences, University of Groningen, University Medical Center Groningen (UMCG), Groningen, the Netherlands
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Abstract
Uveal melanoma (UM), a rare cancer of the eye, is distinct from cutaneous melanoma by its etiology, the mutation frequency and profile, and its clinical behavior including resistance to targeted therapy and immune checkpoint blockers. Primary disease is efficiently controlled by surgery or radiation therapy, but about half of UMs develop distant metastasis mostly to the liver. Survival of patients with metastasis is below 1 year and has not improved in decades. Recent years have brought a deep understanding of UM biology characterized by initiating mutations in the G proteins GNAQ and GNA11. Cytogenetic alterations, in particular monosomy of chromosome 3 and amplification of the long arm of chromosome 8, and mutation of the BRCA1-associated protein 1, BAP1, a tumor suppressor gene, or the splicing factor SF3B1 determine UM metastasis. Cytogenetic and molecular profiling allow for a very precise prognostication that is still not matched by efficacious adjuvant therapies. G protein signaling has been shown to activate the YAP/TAZ pathway independent of HIPPO, and conventional signaling via the mitogen-activated kinase pathway probably also contributes to UM development and progression. Several lines of evidence indicate that inflammation and macrophages play a pro-tumor role in UM and in its hepatic metastases. UM cells benefit from the immune privilege in the eye and may adopt several mechanisms involved in this privilege for tumor escape that act even after leaving the niche. Here, we review the current knowledge of the biology of UM and discuss recent approaches to UM treatment.
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Affiliation(s)
- Adriana Amaro
- Laboratory of Molecular Pathology, Department of Integrated Oncology Therapies, IRCCS AOU San Martino - IST Istituto Nazionale per la Ricerca sul Cancro, L.go Rosanna Benzi 10, 16132, Genoa, Italy
| | - Rosaria Gangemi
- Laboratory of Biotherapies, Department of Integrated Oncology Therapies, IRCCS AOU San Martino - IST Istituto Nazionale per la Ricerca sul Cancro, Genoa, Italy
| | - Francesca Piaggio
- Laboratory of Molecular Pathology, Department of Integrated Oncology Therapies, IRCCS AOU San Martino - IST Istituto Nazionale per la Ricerca sul Cancro, L.go Rosanna Benzi 10, 16132, Genoa, Italy
| | - Giovanna Angelini
- Laboratory of Molecular Pathology, Department of Integrated Oncology Therapies, IRCCS AOU San Martino - IST Istituto Nazionale per la Ricerca sul Cancro, L.go Rosanna Benzi 10, 16132, Genoa, Italy
| | - Gaia Barisione
- Laboratory of Biotherapies, Department of Integrated Oncology Therapies, IRCCS AOU San Martino - IST Istituto Nazionale per la Ricerca sul Cancro, Genoa, Italy
| | - Silvano Ferrini
- Laboratory of Biotherapies, Department of Integrated Oncology Therapies, IRCCS AOU San Martino - IST Istituto Nazionale per la Ricerca sul Cancro, Genoa, Italy
| | - Ulrich Pfeffer
- Laboratory of Molecular Pathology, Department of Integrated Oncology Therapies, IRCCS AOU San Martino - IST Istituto Nazionale per la Ricerca sul Cancro, L.go Rosanna Benzi 10, 16132, Genoa, Italy.
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Foster WJ, Aliyar HA, Hamilton P, Ravi N. Internal Osmotic Pressure as a Mechanism of Retinal Attachment in a Vitreous Substitute. J BIOACT COMPAT POL 2016. [DOI: 10.1177/0883911506064368] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
In this study, the possibility of using the internal osmotic pressure of intraocular polymeric hydrogel materials to attach the retina in the repair of a retinal tear or hole was investigated. This is in contrast to the conventional methods of retinal detachment repair (intraocular gas, polydimethylsiloxane, or n-perfluorooctane), which rely on surface tension and have recognized limits. The system selected for implementation of this scheme was based on an acrylamide copolymer that was crosslinked in an aqueous solution to provide a transparent hydrogel which allowed control of the swelling pressure. Synthetic hydrogels, such as those selected here, provide an alternative to materials currently used as vitreous prostheses.
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Affiliation(s)
| | | | - Paul Hamilton
- Surgical Services, St. Louis VA Medical Center, St. Louis, MO, 63106, USA; Department of Ophthalmology and Visual Sciences, Washington University, St. Louis, MO 63110, USA
| | - Nathan Ravi
- Surgical Services, St. Louis VA Medical Center, St. Louis, MO, 63106, USA; Department of Ophthalmology and Visual Sciences, Washington University, St. Louis, MO 63110, USA
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Syed Z, Stewart MW. Age-dependent vitreous separation from the macula in a clinic population. Clin Ophthalmol 2016; 10:1237-43. [PMID: 27462138 PMCID: PMC4940013 DOI: 10.2147/opth.s99635] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Background Vitreous degeneration begins soon after birth and accelerates throughout life. Vitreous liquefaction with a slowly progressive separation of the posterior hyaloid from the peripheral macula usually leads to complete posterior vitreous detachment. The purpose of this study is to measure the age-related prevalence of partial vitreous separation and the length of residual vitreous adhesion in an ophthalmology clinic population. Methods Patients examined by the senior author (MWS) during a 6-month period were included in a retrospective chart review. Demographic data and spectral domain optical coherence tomography scan results were gathered. Data analysis with descriptive statistics focused on the prevalence and extent of partial vitreous separation. Results The mean age of the study patients was 69.9 years, and 62% were phakic. The highest prevalence of partial posterior hyaloid separation from the internal limiting membrane (71.2%) was seen in the 50- to 54-year age group. This prevalence rate steadily decreased to 5.6% in the 95- to 99-year age group. The prevalence of complete vitreous detachment as determined by slit-lamp biomicroscopy increased from 1.7% in the <50-year age group to a maximum of 29.2% in the 75- to 79-year group. The length of vitreomacular adhesion averaged 4.6 mm in the 50- to 54-year age group and steadily decreased to 2.1 mm in the 90- to 95-year group. Conclusion Vitreomacular separation affects the majority of eyes in the sixth decade of life. The prevalence of partial vitreous separation decreases with advancing age, probably because an increasing number of these patients progress to complete posterior vitreous detachment.
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Affiliation(s)
| | - Michael W Stewart
- Department of Ophthalmology, Mayo School of Medicine, Jacksonville, FL, USA
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Morozova S, Hamilton P, Ravi N, Muthukumar M. Development of a Vitreous Substitute: Incorporating Charges and Fibrous Structures in Synthetic Hydrogel Materials. Macromolecules 2016. [DOI: 10.1021/acs.macromol.6b00885] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Svetlana Morozova
- Polymer
Science and Engineering, UMass Amherst, Amherst, Massachusetts 01003
| | - Paul Hamilton
- Ophthalmology & Visual Sciences, Washington University School of Medicine, St. Louis, Missouri
| | - Nathan Ravi
- Ophthalmology & Visual Sciences, Washington University School of Medicine, St. Louis, Missouri
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Decreased hyaluronan concentration during primary rhegmatogenous retinal detachment. Eur J Ophthalmol 2016; 26:633-638. [PMID: 27198637 DOI: 10.5301/ejo.5000802] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/21/2016] [Indexed: 11/20/2022]
Abstract
PURPOSE To evaluate the concentration and molecular weight of hyaluronan (HA) polysaccharides as well as hyaluronidase activity in patients with rhegmatogenous retinal detachment (RRD). METHODS Twenty vitreous samples from 20 patients with RRD and 19 samples from 19 patients with idiopathic epiretinal membrane, macular hole, or vitreomacular traction syndrome were collected during surgical management with pars plana vitrectomy. The molecular weight of various HA fragments was assessed using agarose gel electrophoresis. Enzyme-linked immunosorbent assay was employed for the measurement of HA (in μg/mL). Hyaluronidase activity was evaluated using substrate (HA) sodium dodecyl sulfate polyacrylamide gel electrophoresis. RESULTS Agarose gel electrophoresis showed that the vitreous of the control group contained HA of high molecular mass, in contrast with the patient group. Mean HA concentration in the patient group was 50.96 μg/mL and differed significantly from that of the control group, which was 271.81 μg/mL (p<0.0005). Hyaluronidase activity was significantly higher in the vitreous of patients with RRD (p = 0.037). CONCLUSIONS The vitreous of patients with RRD is characterized by decreased HA concentration compared to controls of the same age and sex and shows higher hyaluronidase catalytic activity. Hyaluronan degradation could be associated with specific vitreous alterations that potentially contribute to retinal break formation and consequently detachment.
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Shah NS, Beebe DC, Lake SP, Filas BA. On the Spatiotemporal Material Anisotropy of the Vitreous Body in Tension and Compression. Ann Biomed Eng 2016; 44:3084-3095. [DOI: 10.1007/s10439-016-1589-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2015] [Accepted: 03/04/2016] [Indexed: 11/29/2022]
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