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Li X, Liang C, Guo Y, Su J, Chen X, Macgregor RB, Zhang RX, Yan H. Clinical Translation of Long-Acting Drug Delivery Systems for Posterior Capsule Opacification Prophylaxis. Pharmaceutics 2023; 15:pharmaceutics15041235. [PMID: 37111720 PMCID: PMC10143098 DOI: 10.3390/pharmaceutics15041235] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2023] [Revised: 04/04/2023] [Accepted: 04/08/2023] [Indexed: 04/29/2023] Open
Abstract
Posterior capsule opacification (PCO) remains the most common cause of vision loss post cataract surgery. The clinical management of PCO formation is limited to either physical impedance of residual lens epithelial cells (LECs) by implantation of specially designed intraocular lenses (IOL) or laser ablation of the opaque posterior capsular tissues; however, these strategies cannot fully eradicate PCO and are associated with other ocular complications. In this review, we critically appraise recent advances in conventional and nanotechnology-based drug delivery approaches to PCO prophylaxis. We focus on long-acting dosage forms, including drug-eluting IOL, injectable hydrogels, nanoparticles and implants, highlighting analysis of their controlled drug-release properties (e.g., release duration, maximum drug release, drug-release half-life). The rational design of drug delivery systems by considering the intraocular environment, issues of initial burst release, drug loading content, delivery of drug combination and long-term ocular safety holds promise for the development of safe and effective pharmacological applications in anti-PCO therapies.
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Affiliation(s)
- Xinyang Li
- Xi'an People's Hospital (Xi'an Fourth Hospital), Shaanxi Eye Hospital, Affiliated People's Hospital of Northwest University, 21 Jiefang Road, Xi'an 710004, China
| | - Chen Liang
- Xi'an People's Hospital (Xi'an Fourth Hospital), Shaanxi Eye Hospital, Affiliated People's Hospital of Northwest University, 21 Jiefang Road, Xi'an 710004, China
| | - Yexuan Guo
- Xi'an Key Laboratory of Stem Cell and Regenerative Medicine, Institute of Medical Research, Northwestern Polytechnical University, 127 West Youyi Road, Xi'an 710072, China
| | - Jing Su
- Xi'an Key Laboratory of Stem Cell and Regenerative Medicine, Institute of Medical Research, Northwestern Polytechnical University, 127 West Youyi Road, Xi'an 710072, China
| | - Xi Chen
- Xi'an People's Hospital (Xi'an Fourth Hospital), Shaanxi Eye Hospital, Affiliated People's Hospital of Northwest University, 21 Jiefang Road, Xi'an 710004, China
| | - Robert B Macgregor
- Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, 144 College Street, Toronto, ON M5S 3M2, Canada
| | - Rui Xue Zhang
- Xi'an Key Laboratory of Stem Cell and Regenerative Medicine, Institute of Medical Research, Northwestern Polytechnical University, 127 West Youyi Road, Xi'an 710072, China
| | - Hong Yan
- Xi'an People's Hospital (Xi'an Fourth Hospital), Shaanxi Eye Hospital, Affiliated People's Hospital of Northwest University, 21 Jiefang Road, Xi'an 710004, China
- Xi'an Key Laboratory of Stem Cell and Regenerative Medicine, Institute of Medical Research, Northwestern Polytechnical University, 127 West Youyi Road, Xi'an 710072, China
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Zhang KK, He WW, Du Y, Zhou YG, Wu X, Zhu J, Zhu XJ, Kang Z, Lu Y. Inhibitory effect of lanosterol on cataractous lens of cynomolgus monkeys using a subconjunctival drug release system. PRECISION CLINICAL MEDICINE 2022; 5:pbac021. [PMID: 36196296 PMCID: PMC9523460 DOI: 10.1093/pcmedi/pbac021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Accepted: 08/16/2022] [Indexed: 11/25/2022] Open
Abstract
Background To evaluate the effect of lanosterol on cataractous lens of cynomolgus monkeys using a subconjunctival drug release system. Methods Nine elder cynomolgus monkeys were used, consisting of three monkeys without cataract as controls, three monkeys with naturally occurring cortical cataract, and three monkeys with nuclear cataract as intervention groups. Nanoparticulated thermogel with lanosterol and fluorescein was administered by subconjunctival injection in the monkeys with cataract. Fluorescence changes of injected thermogel and cataract progression were observed. Lanosterol concentration in aqueous humor, solubility changes in lens proteins, and oxidative stress levels were analyzed in the lenses of the control and intervention groups. Results Injected thermogel showed decreased fluorescence during follow up. Lanosterol concentration in aqueous humor increased in the first 2 weeks and then gradually decreased, which was in accordance with the changes in cortical lens clarity. However, lenses with nuclear opacification showed little change. In the cortical region of lenses with cortical cataract, solubility of α-crystallin was significantly increased after administration of lanosterol, as well as the reduction of oxidative stress. Conclusions We demonstrated the effect of lanosterol on cataract progression based on in vivo models of primates. Lanosterol showed a short-term and reliable reversal effect on reducing cataract severity in cortical cataract in the early stages, possibly due to the increase in the solubility of lens proteins and changes in the oxidative stress status. Lanosterol administration using subconjunctival drug release system could be a promising nonsurgical approach for future clinical studies of cataract prevention and treatment.
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Affiliation(s)
- Ke-Ke Zhang
- Eye Institute, Eye & ENT Hospital, Fudan University , Shanghai 200031 , China
- Department of Ophthalmology, Eye & ENT Hospital, Fudan University , Shanghai 200031 , China
- NHC Key Laboratory of Myopia (Fudan University) , Shanghai 200031 , China
- Key Laboratory of Myopia, Chinese Academy of Medical Sciences , Shanghai 200031 , China
| | - Wen-Wen He
- Eye Institute, Eye & ENT Hospital, Fudan University , Shanghai 200031 , China
- Department of Ophthalmology, Eye & ENT Hospital, Fudan University , Shanghai 200031 , China
- NHC Key Laboratory of Myopia (Fudan University) , Shanghai 200031 , China
- Key Laboratory of Myopia, Chinese Academy of Medical Sciences , Shanghai 200031 , China
| | - Yu Du
- Eye Institute, Eye & ENT Hospital, Fudan University , Shanghai 200031 , China
- Department of Ophthalmology, Eye & ENT Hospital, Fudan University , Shanghai 200031 , China
- NHC Key Laboratory of Myopia (Fudan University) , Shanghai 200031 , China
- Key Laboratory of Myopia, Chinese Academy of Medical Sciences , Shanghai 200031 , China
| | - Yu-gui Zhou
- Guangzhou Women and Children's Medical Center, Guangzhou Medical University , Guangzhou 510620 , China
- Institute for Genomic Medicine, Institute of Engineering in Medicine, and Shiley Eye Institute, University of California , San Diego, La Jolla, CA 92093 , USA
| | - Xiaokang Wu
- Smidt Heart Institute , Cedars-Sinai Medical Center, Los Angeles, CA 90048 , USA
| | - Jie Zhu
- Guangzhou Women and Children's Medical Center, Guangzhou Medical University , Guangzhou 510620 , China
- Guangzhou KangRui Biological Pharmaceutical Technology Company , Guangzhou 510440 , China
| | - Xiang-Jia Zhu
- Eye Institute, Eye & ENT Hospital, Fudan University , Shanghai 200031 , China
- Department of Ophthalmology, Eye & ENT Hospital, Fudan University , Shanghai 200031 , China
- NHC Key Laboratory of Myopia (Fudan University) , Shanghai 200031 , China
- Key Laboratory of Myopia, Chinese Academy of Medical Sciences , Shanghai 200031 , China
| | - Zhang Kang
- Faculty of Medicine, Macau University of Science and Technology , Taipa 999078 , Macau, China
| | - Yi Lu
- Eye Institute, Eye & ENT Hospital, Fudan University , Shanghai 200031 , China
- Department of Ophthalmology, Eye & ENT Hospital, Fudan University , Shanghai 200031 , China
- NHC Key Laboratory of Myopia (Fudan University) , Shanghai 200031 , China
- Key Laboratory of Myopia, Chinese Academy of Medical Sciences , Shanghai 200031 , China
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Konopińska J, Młynarczyk M, Dmuchowska DA, Obuchowska I. Posterior Capsule Opacification: A Review of Experimental Studies. J Clin Med 2021; 10:jcm10132847. [PMID: 34199147 PMCID: PMC8269180 DOI: 10.3390/jcm10132847] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2021] [Revised: 06/13/2021] [Accepted: 06/24/2021] [Indexed: 11/16/2022] Open
Abstract
Posterior capsule opacification (PCO) is the most common complication of cataract surgery. It causes a gradual deterioration of visual acuity, which would otherwise improve after a successful procedure. Despite recent advances in ophthalmology, this complication has not been eradicated, and the incidence of PCO can be as high as 10%. This article reviews the literature concerning the pathomechanism of PCO and examines the biochemical pathways involved in its formation and methods to prevent this complication. We also review the reported tests performed in cell cultures under laboratory conditions and in experimental animal models and in ex vivo human lens capsules. Finally, we describe research involving human eyes in the clinical setting and pharmacological methods that may reduce the frequency of PCO. Due to the multifactorial etiology of PCO, in vitro studies make it possible to assess the factors contributing to its complications and search for new therapeutic targets. Not all pathways involved in cell proliferation, migration, and contraction of the lens capsule are reproducible in laboratory conditions; moreover, PCO in humans and laboratory animals may be additionally stimulated by various degrees of postoperative reactions depending on the course of surgery. Therefore, further studies are necessary.
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van Kooten TG, Koopmans SA, Terwee T, Langner S, Stachs O, Guthoff RF. Long-term prevention of capsular opacification after lens-refilling surgery in a rabbit model. Acta Ophthalmol 2019; 97:e860-e870. [PMID: 30900825 PMCID: PMC6766982 DOI: 10.1111/aos.14096] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2018] [Accepted: 03/03/2019] [Indexed: 12/21/2022]
Abstract
Purpose To reduce capsular opacification by a peri‐surgical treatment of the lens capsule with drugs in an in vivo rabbit model. Lens‐refilling surgery is a potential therapeutic intervention to treat patients with a cataract lens. The lens material is replaced with an injectable (bio)polymer that retains the natural mechanical and optical lens properties, therewith allowing accommodation. The occurrence of capsular opacification mediated by lens epithelial cells negatively affects accommodation and vision and should be avoided in this lens restoration approach. Methods An in vivo rabbit animal model was used with lens replacement with a silicone‐based gel‐like polymer and concurrent treatment of the lens epithelium with drugs. A case‐study approach was applied as both drug combinations and implantation times were varied. The following drugs were investigated for their potential to prevent capsular opacification long‐term: actinomycin D, methotrexate, paclitaxel and Tween‐20. All were administered in a hyaluronic acid vehicle. The rabbits were clinically followed for periods up to 4 years postimplantation. Eyes, corneas and lenses were analysed post‐mortem using MRI and confocal microscopy. Results Treatment combinations containing actinomycin D generally led to the least appearance of capsular fibrosis. The use of Tween‐20 or paclitaxel without actinomycin D resulted in much earlier and pronounced fibrotic responses. The aspect of capsular opacification was highly variable in individual animals. Application of the drugs in a hyaluronic acid vehicle appeared to be a safe method that spared the corneal endothelium. Conclusion The feasibility of long‐term prevention of fibrosis over a period of more than 4 years has been demonstrated in lens refilling in the rabbit model.
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Affiliation(s)
- Theo G. van Kooten
- Department of Biomedical Engineering University of Groningen University Medical Center Groningen Groningen The Netherlands
| | - Steven A. Koopmans
- Department of Ophthalmology University of Groningen University Medical Center Groningen Groningen The Netherlands
| | | | - Sönke Langner
- Institute for Diagnostic and Interventional Radiology Pediatric and Neuroradiology University Medicine Rostock Rostock Germany
| | - Oliver Stachs
- Department of Ophthalmology University of Rostock Rostock Germany
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Wertheimer C, Kreutzer TC, Dirisamer M, Eibl-Lindner K, Kook D, Priglinger S, Mayer WJ. Effect of femtosecond laser-assisted lens surgery on posterior capsule opacification in the human capsular bag in vitro. Acta Ophthalmol 2017; 95:e85-e88. [PMID: 27288315 DOI: 10.1111/aos.13103] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2015] [Accepted: 03/28/2016] [Indexed: 11/28/2022]
Abstract
PURPOSE To compare posterior capsule opacification (PCO) by observing lens epithelial cell growth in the human capsular bag in vitro between conventional lens surgery using phacoemulsification (Phaco) technique and femtosecond laser-assisted lens surgery (FLACS). METHODS For the in vitro human capsular bag model, 18 cadaver eyes from nine human donors underwent three types of lens surgery. Three groups consisting of six capsular bags were established, that is FLACS, Phaco and extracapsular lens extraction (ECCE). The capsular bag was transferred into equal cell culture conditions after using one of the defined surgical approaches. Cellular growth of lens epithelial cells was observed and photo-documented. The time until full cell-coverage of the capsular bag was measured. RESULTS The human capsular bag model can be successfully prepared using FLACS. There was no statistically significant difference in time until cell-coverage of the human donor capsular bag in vitro in all three surgical settings (ECCE versus Phaco p = 0.6; ECCE versus FLACS p = 1.0; Phaco versus FLACS p = 1.0). CONCLUSIONS In our in vitro human capsular bag model, we could not observe a statistically significant difference in PCO formation using different surgical approaches of lens extraction. Therefore, PCO formation might not be attributed to the type of surgery. Furthermore, this study shows that FLACS can be used for the human capsular bag model preparation and validates the human capsular bag model for future research.
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Affiliation(s)
- Christian Wertheimer
- Department of Ophthalmology; Ludwig-Maximilians-University Munich; Munich Germany
| | - Thomas C. Kreutzer
- Department of Ophthalmology; Ludwig-Maximilians-University Munich; Munich Germany
| | - Martin Dirisamer
- Department of Ophthalmology; Ludwig-Maximilians-University Munich; Munich Germany
| | - Kirsten Eibl-Lindner
- Department of Ophthalmology; Ludwig-Maximilians-University Munich; Munich Germany
| | - Daniel Kook
- Department of Ophthalmology; Ludwig-Maximilians-University Munich; Munich Germany
| | - Siegfried Priglinger
- Department of Ophthalmology; Ludwig-Maximilians-University Munich; Munich Germany
| | - Wolfgang J. Mayer
- Department of Ophthalmology; Ludwig-Maximilians-University Munich; Munich Germany
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Nibourg LM, Gelens E, Nibourg SAF, de Jong MR, Kuijer R, van Kooten TG, Koopmans SA. Effects of peptide ratios in nanofibre-based hydrogels for the prevention of capsular opacification. Acta Ophthalmol 2016; 94:721-729. [PMID: 27062370 DOI: 10.1111/aos.13047] [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: 10/23/2015] [Accepted: 02/05/2016] [Indexed: 12/13/2022]
Abstract
PURPOSE To moderate the capsular opacification (CO) response after lens surgery, an experimental study was performed in which nanofibre-based hydrogels (nanogels) with different ratios of attached peptides were applied to provide extracellular matrix-related cues for lens epithelial cells (LECs) in a porcine eye model. METHODS The lens content was removed, and the capsules were refilled with nanogel. Lenses were divided into two groups, the first group (n = 34) was refilled with nanogels containing different ratios of two laminin-derived peptides (IKVAV + YIGSR), and the latter group (n = 26) was refilled with nanogel combinations of a fibronectin-derived and a type IV collagen-derived peptide (RGDS + DGEA). Two lenses were refilled with culture medium to investigate the effect of the medium on LECs. After refilling, lenses were extracted and cultured for 3 weeks. Lens epithelial cells (LECs) were assessed for morphology and alpha-smooth muscle actin (αSMA) expression using confocal laser scanning microscopy. RESULTS Differences were seen in cell morphology between lenses refilled with nanogels with IKVAV + YIGSR and RGDS + DGEA peptides. In nanogels with IKVAV + YIGSR peptides, differences in LEC morphology were largest when ratios between the peptides were unequal, whereas LEC responses from the RGDS + DGEA refilled groups showed variation in LEC morphology dependent on the total quantity of mixed-in peptides. The culture medium did not induce proliferation or transformation of LECs. CONCLUSIONS Ratios and concentrations of cell adhesion-mediating peptides both can direct the LEC response, depending on the adhesion molecules of origin, by influencing LEC proliferation and transformation. Nanogels with incorporated peptides may be tuned towards CO prevention.
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Affiliation(s)
- Lisanne M. Nibourg
- Department of Ophthalmology; University of Groningen, University Medical Center Groningen; Groningen The Netherlands
- Laboratory for Experimental Ophthalmology; University of Groningen, University Medical Center Groningen; Groningen The Netherlands
- W.J. Kolff Institute; University of Groningen, University Medical Center Groningen; Groningen The Netherlands
| | | | - Simone A. F. Nibourg
- Department of Ophthalmology; University of Groningen, University Medical Center Groningen; Groningen The Netherlands
- Laboratory for Experimental Ophthalmology; University of Groningen, University Medical Center Groningen; Groningen The Netherlands
| | | | - Roel Kuijer
- W.J. Kolff Institute; University of Groningen, University Medical Center Groningen; Groningen The Netherlands
- Department of Biomedical Engineering; University of Groningen, University Medical Center Groningen; Groningen The Netherlands
| | - Theo G. van Kooten
- W.J. Kolff Institute; University of Groningen, University Medical Center Groningen; Groningen The Netherlands
- Department of Biomedical Engineering; University of Groningen, University Medical Center Groningen; Groningen The Netherlands
| | - Steven A. Koopmans
- Department of Ophthalmology; University of Groningen, University Medical Center Groningen; Groningen The Netherlands
- W.J. Kolff Institute; University of Groningen, University Medical Center Groningen; Groningen The Netherlands
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Nibourg LM, Gelens E, de Jong MR, Kuijer R, van Kooten TG, Koopmans SA. Nanofiber-based hydrogels with extracellular matrix-based synthetic peptides for the prevention of capsular opacification. Exp Eye Res 2015; 143:60-7. [PMID: 26474493 DOI: 10.1016/j.exer.2015.10.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Revised: 09/23/2015] [Accepted: 10/02/2015] [Indexed: 11/29/2022]
Abstract
Nanofiber-based hydrogels (nanogels) with different, covalently bound peptides were used as an extracellular environment for lens epithelial cells (LECs) in order to modulate the capsular opacification (CO) response after lens surgery in a porcine eye model. Lenses were divided into 15 groups (n = 4 per group), the lens content was removed and the empty capsules were refilled with nanogel without peptides and nanogels with 13 combinations of 5 different peptides: two laminin-derived, two fibronectin-derived, and one collagen IV-derived peptide representing cell adhesion motifs. A control group of 4 lenses was refilled with hyaluronan. After refilling, lenses were extracted from the porcine eye and cultured for three weeks. LECs were assessed for morphology and alpha smooth muscle actin (αSMA) expression using confocal laser scanning microscopy. Compared to hyaluronan controls, lenses filled with nanogel had less CO formation, indicated by a lower αSMA expression (P = 0.004). Microscopy showed differences in morphological cell response within the nanogel refilled groups. αSMA expression in these groups was highest in lenses refilled with nanogel without peptides (9.54 ± 11.29%). Overall, LEC transformation is reduced by the presence of nanogels and the response is improved even further by incorporation of extracellular matrix peptides representing adhesion motifs. Thus, nanomaterials targeting biological pathways, in our case interactions with integrin signaling, are a promising avenue toward reduction of CO. Further research is needed to optimize nanogel-peptide combinations that fully prevent CO.
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Affiliation(s)
- Lisanne M Nibourg
- University of Groningen, University Medical Center Groningen, Dept. of Ophthalmology, Hanzeplein 1, 9713 GZ Groningen, The Netherlands; University of Groningen, University Medical Center Groningen, Laboratory for Experimental Ophthalmology, Hanzeplein 1, 9713 GZ Groningen, The Netherlands; University of Groningen, University Medical Center Groningen, W.J. Kolff Institute, Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands.
| | - Edith Gelens
- Nano Fiber Matrices B.V., Zernikepark 6-8, 9747 AN Groningen, The Netherlands
| | - Menno R de Jong
- Nano Fiber Matrices B.V., Zernikepark 6-8, 9747 AN Groningen, The Netherlands
| | - Roel Kuijer
- University of Groningen, University Medical Center Groningen, W.J. Kolff Institute, Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands; University of Groningen, University Medical Center Groningen, Dept. of Biomedical Engineering, Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands
| | - Theo G van Kooten
- University of Groningen, University Medical Center Groningen, W.J. Kolff Institute, Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands; University of Groningen, University Medical Center Groningen, Dept. of Biomedical Engineering, Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands
| | - Steven A Koopmans
- University of Groningen, University Medical Center Groningen, Dept. of Ophthalmology, Hanzeplein 1, 9713 GZ Groningen, The Netherlands; University of Groningen, University Medical Center Groningen, W.J. Kolff Institute, Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands
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Prevention of posterior capsular opacification. Exp Eye Res 2015; 136:100-15. [PMID: 25783492 DOI: 10.1016/j.exer.2015.03.011] [Citation(s) in RCA: 107] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2014] [Revised: 02/04/2015] [Accepted: 03/13/2015] [Indexed: 01/22/2023]
Abstract
Posterior capsular opacification (PCO) is a common complication of cataract surgery. The development of PCO is due to a combination of the processes of proliferation, migration, and transdifferentiation of residual lens epithelial cells (LECs) on the lens capsule. In the past decades, various forms of PCO prevention have been examined, including adjustments of techniques and intraocular lens materials, pharmacological treatments, and prevention by interfering with biological processes in LECs. The only method so far that seems effective is the implantation of an intraocular lens with sharp edged optics to mechanically prevent PCO formation. In this review, current knowledge of the prevention of PCO will be described. We illustrate the biological pathways underlying PCO formation and the various approaches to interfere with the biological processes to prevent PCO. In this type of prevention, the use of nanotechnological advances can play a role.
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Nibourg LM, Sharma PK, van Kooten TG, Koopmans SA. Changes in lens stiffness due to capsular opacification in accommodative lens refilling. Exp Eye Res 2015; 134:148-54. [PMID: 25704214 DOI: 10.1016/j.exer.2015.02.015] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2014] [Revised: 02/17/2015] [Accepted: 02/18/2015] [Indexed: 12/19/2022]
Abstract
Accommodation may be restored to presbyopic lenses by refilling the lens capsular bag with a soft polymer. After this accommodative lens refilling prevention of capsular opacification is a requirement, since capsular opacification leads to a decreased clarity of the refilled lens. It has been hypothesized that capsular fibrosis causing the capsular opacification results in increased stiffness of the lens capsular bag, therewith contributing to a decrease in accommodative amplitude of the lens. However, the change in viscoelastic properties of refilled lenses due to capsular fibrosis has never been measured directly. In this study we examined natural lenses from enucleated porcine eyes and refilled lenses directly after refilling and after three months of culturing, when capsular fibrosis had developed, and determined their viscoelastic properties with a low load compression tester. Control refilled lenses were included in which capsular opacification was prevented by treatment with actinomycin D. We related lens stiffening to the degree of capsular opacification, as derived from the microscopic images taken with a confocal laser scanning microscope. Overall, the refilled lenses directly after refilling were softer than refilled lenses after three months of culturing, and refilled lenses treated with actinomycin D were softer compared with untreated refilled lenses. The degree of capsular opacification as assessed by microscopy corresponds to an increase in lens stiffness. This indicates that the viscoelastic properties of the refilled lens are influenced by capsular fibrosis and modulated by treatment of the lens epithelium. In conclusion, this study shows that the development of capsular fibrosis negatively affects the viscoelastic properties of isolated, cultured refilled lenses.
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Affiliation(s)
- Lisanne M Nibourg
- University of Groningen, University Medical Center Groningen, Dept. of Ophthalmology, Hanzeplein 1, 9713 GZ Groningen, The Netherlands; University of Groningen, University Medical Center Groningen, Laboratory for Experimental Ophthalmology, Hanzeplein 1, 9713 GZ Groningen, The Netherlands; University of Groningen, University Medical Center Groningen, W.J. Kolff Institute, Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands.
| | - Prashant K Sharma
- University of Groningen, University Medical Center Groningen, W.J. Kolff Institute, Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands; University of Groningen, University Medical Center Groningen, Dept. of Biomedical Engineering, Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands
| | - Theo G van Kooten
- University of Groningen, University Medical Center Groningen, W.J. Kolff Institute, Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands; University of Groningen, University Medical Center Groningen, Dept. of Biomedical Engineering, Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands
| | - Steven A Koopmans
- University of Groningen, University Medical Center Groningen, Dept. of Ophthalmology, Hanzeplein 1, 9713 GZ Groningen, The Netherlands; University of Groningen, University Medical Center Groningen, W.J. Kolff Institute, Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands
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