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Maceo Heilman B, Mote K, Batchelor W, Rowaan C, Gonzalez A, Arrieta E, Ruggeri M, Ziebarth N, Cabrera-Ghayouri S, Dibas M, Parel JM, Manns F. Effect of compound treatments on mouse lens viscoelasticity. Exp Eye Res 2024; 246:109992. [PMID: 38972445 DOI: 10.1016/j.exer.2024.109992] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2024] [Revised: 06/18/2024] [Accepted: 07/04/2024] [Indexed: 07/09/2024]
Abstract
Previous studies have shown that pharmaceutical agents such as lipoic acid have the ability to soften the lens, presenting a promising avenue for treating presbyopia. One obstacle encountered in the preclinical stage of such agents is the need for precise measurements of lens elasticity in experimental models. This study aimed to evaluate the effects of 25-hydroxycholesterol, lipoic acid, and obeticholic acid on the viscoelastic properties of mouse lenses using a custom-built elastometer system. Data were acquired on lenses from C57BL/6J female mice from two age groups: young (age: 8-10 weeks) and old (age: 32-43 weeks). OD lenses were used as the control and OS lenses were treated. Control lenses were immersed in Dulbecco's Modified Eagle Medium (DMEM) and treatment lenses were immersed in a compound solution containing 25-hydroxycholesterol (5 young and 5 old), lipoic acid at 2.35 mM (5 young and 5 old), lipoic acid at 0.66 mM (5 old), or obeticholic acid (5 old) at 37 °C for 18 h. After treatment, the mouse lenses were placed in a DMEM-filled chamber within a custom-built elastometer system that recorded the load and lens shape as the lens was compressed by 600 μm at a speed of 50 μm/s. The load was continuously recorded during compression and during stress-relaxation. The compression phase was fit with a linear function to quantify lens stiffness. The stress-relaxation phase was fit with a 3-term exponential relaxation model providing relaxation time constants (t1, t2, t3), and equilibrium load. The lens stiffness, time constants and equilibrium load were compared for the control and treated groups. Results revealed an increase in stiffness with age for the control group (young: 1.16 ± 0.11 g/mm, old: 1.29 ± 0.14 g/mm) and relaxation time constants decreased with age (young: t1 = 221.9 ± 29.0 s, t2 = 24.7 ± 3.8 s, t3 = 3.12 ± 0.87 s, old: t1 = 183.0 ± 22.0 s, t2 = 20.6 ± 2.6 s and t3 = 2.24 ± 0.43 s). Among the compounds tested, only 25-hydroxycholesterol produced statistically significant changes in the lens stiffness, relaxation time constants, and equilibrium load. In conclusion, older mouse lenses are stiffer and less viscous than young mouse lenses. Notably, no significant change in lens stiffness was observed following treatment with lipoic acid, contrary to previous findings.
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Affiliation(s)
- Bianca Maceo Heilman
- Ophthalmic Biophysics Center, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, USA; Department of Biomedical Engineering, University of Miami College of Engineering, Coral Gables, FL, USA
| | - Kelly Mote
- Ophthalmic Biophysics Center, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, USA; Department of Biomedical Engineering, University of Miami College of Engineering, Coral Gables, FL, USA
| | - Wyndham Batchelor
- Department of Biomedical Engineering, University of Miami College of Engineering, Coral Gables, FL, USA
| | - Cornelis Rowaan
- Ophthalmic Biophysics Center, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Alex Gonzalez
- Ophthalmic Biophysics Center, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Esdras Arrieta
- Ophthalmic Biophysics Center, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Marco Ruggeri
- Ophthalmic Biophysics Center, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Noel Ziebarth
- Department of Biomedical Engineering, University of Miami College of Engineering, Coral Gables, FL, USA
| | | | | | - Jean-Marie Parel
- Ophthalmic Biophysics Center, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, USA; Department of Biomedical Engineering, University of Miami College of Engineering, Coral Gables, FL, USA
| | - Fabrice Manns
- Ophthalmic Biophysics Center, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, USA; Department of Biomedical Engineering, University of Miami College of Engineering, Coral Gables, FL, USA.
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2
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Cvekl A, Vijg J. Aging of the eye: Lessons from cataracts and age-related macular degeneration. Ageing Res Rev 2024; 99:102407. [PMID: 38977082 DOI: 10.1016/j.arr.2024.102407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2024] [Revised: 06/18/2024] [Accepted: 07/01/2024] [Indexed: 07/10/2024]
Abstract
Aging is the greatest risk factor for chronic human diseases, including many eye diseases. Geroscience aims to understand the effects of the aging process on these diseases, including the genetic, molecular, and cellular mechanisms that underlie the increased risk of disease over the lifetime. Understanding of the aging eye increases general knowledge of the cellular physiology impacted by aging processes at various biological extremes. Two major diseases, age-related cataract and age-related macular degeneration (AMD) are caused by dysfunction of the lens and retina, respectively. Lens transparency and light refraction are mediated by lens fiber cells lacking nuclei and other organelles, which provides a unique opportunity to study a single aging hallmark, i.e., loss of proteostasis, within an environment of limited metabolism. In AMD, local dysfunction of the photoreceptors/retinal pigmented epithelium/Bruch's membrane/choriocapillaris complex in the macula leads to the loss of photoreceptors and eventually loss of central vision, and is driven by nearly all the hallmarks of aging and shares features with Alzheimer's disease, Parkinson's disease, cardiovascular disease, and diabetes. The aging eye can function as a model for studying basic mechanisms of aging and, vice versa, well-defined hallmarks of aging can be used as tools to understand age-related eye disease.
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Affiliation(s)
- Ales Cvekl
- Departments of Genetics and Ophthalmology and Visual Sciences, Albert Einstein College of Medicine, Bronx, NY 10461, USA.
| | - Jan Vijg
- Departments of Genetics and Ophthalmology and Visual Sciences, Albert Einstein College of Medicine, Bronx, NY 10461, USA.
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3
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Donaldson PJ, Petrova RS, Nair N, Chen Y, Schey KL. Regulation of water flow in the ocular lens: new roles for aquaporins. J Physiol 2024; 602:3041-3056. [PMID: 37843390 PMCID: PMC11018719 DOI: 10.1113/jp284102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Accepted: 09/28/2023] [Indexed: 10/17/2023] Open
Abstract
The ocular lens is an important determinant of overall vision quality whose refractive and transparent properties change throughout life. The lens operates an internal microcirculation system that generates circulating fluxes of ions, water and nutrients that maintain the transparency and refractive properties of the lens. This flow of water generates a substantial hydrostatic pressure gradient which is regulated by a dual feedback system that uses the mechanosensitive channels TRPV1 and TRPV4 to sense decreases and increases, respectively, in the pressure gradient. This regulation of water flow (pressure) and hence overall lens water content, sets the two key parameters, lens geometry and the gradient of refractive index, which determine the refractive properties of the lens. Here we focus on the roles played by the aquaporin family of water channels in mediating lens water fluxes, with a specific focus on AQP5 as a regulated water channel in the lens. We show that in addition to regulating the activity of ion transporters, which generate local osmotic gradients that drive lens water flow, the TRPV1/4-mediated dual feedback system also modulates the membrane trafficking of AQP5 in the anterior influx pathway and equatorial efflux zone of the lens. Since both lens pressure and AQP5-mediated water permeability (P H 2 O ${P_{{{\mathrm{H}}_{\mathrm{2}}}{\mathrm{O}}}}$ ) can be altered by changes in the tension applied to the lens surface via modulating ciliary muscle contraction we propose extrinsic modulation of lens water flow as a potential mechanism to alter the refractive properties of the lens to ensure light remains focused on the retina throughout life.
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Affiliation(s)
- Paul J. Donaldson
- Department of Physiology, School of Medical Sciences, New Zealand National Eye Center, University of Auckland, Auckland, New Zealand
| | - Rosica S. Petrova
- Department of Physiology, School of Medical Sciences, New Zealand National Eye Center, University of Auckland, Auckland, New Zealand
| | - Nikhil Nair
- Department of Physiology, School of Medical Sciences, New Zealand National Eye Center, University of Auckland, Auckland, New Zealand
| | - Yadi Chen
- Department of Physiology, School of Medical Sciences, New Zealand National Eye Center, University of Auckland, Auckland, New Zealand
| | - Kevin L. Schey
- Department of Biochemistry, Vanderbilt University, Nashville, TN, USA
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4
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Ehrlich H, Voronkina A, Tabachniсk K, Kubiak A, Ereskovsky A, Jesionowski T. Silactins and Structural Diversity of Biosilica in Sponges. Biomimetics (Basel) 2024; 9:393. [PMID: 39056834 PMCID: PMC11274843 DOI: 10.3390/biomimetics9070393] [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: 05/29/2024] [Revised: 06/23/2024] [Accepted: 06/24/2024] [Indexed: 07/28/2024] Open
Abstract
Sponges (phylum Porifera) were among the first metazoans on Earth, and represent a unique global source of highly structured and diverse biosilica that has been formed and tested over more than 800 million years of evolution. Poriferans are recognized as a unique archive of siliceous multiscaled skeletal constructs with superficial micro-ornamentation patterned by biopolymers. In the present study, spicules and skeletal frameworks of selected representatives of sponges in such classes as Demospongiae, Homoscleromorpha, and Hexactinellida were desilicified using 10% HF with the aim of isolating axial filaments, which resemble the shape and size of the original structures. These filaments were unambiguously identified in all specimens under study as F-actin, using the highly specific indicators iFluor™ 594-Phalloidin, iFluor™ 488-Phalloidin, and iFluor™ 350-Phalloidin. The identification of this kind of F-actins, termed for the first time as silactins, as specific pattern drivers in skeletal constructs of sponges opens the way to the fundamental understanding of their skeletogenesis. Examples illustrating the biomimetic potential of sophisticated poriferan biosilica patterned by silactins are presented and discussed.
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Affiliation(s)
- Hermann Ehrlich
- Center of Advanced Technology, Adam Mickiewicz University, Uniwersytetu Poznańskiego 10, 61-614 Poznan, Poland;
- Faculty of Chemical Technology, Institute of Chemical Technology and Engineering, Poznan University of Technology, Berdychowo 4, 60-965 Poznan, Poland
| | - Alona Voronkina
- Pharmacy Department, National Pirogov Memorial Medical University, Vinnytsya, Pirogov Street 56, 21018 Vinnytsia, Ukraine;
| | - Konstantin Tabachniсk
- International Institute of Biomineralogy GmbH, Am St.-Niclas Schacht 13, 09599 Freiberg, Germany
| | - Anita Kubiak
- Center of Advanced Technology, Adam Mickiewicz University, Uniwersytetu Poznańskiego 10, 61-614 Poznan, Poland;
- Faculty of Chemistry, Adam Mickiewicz University, Uniwersytetu Poznanskiego 8, 61-614 Poznan, Poland
| | - Alexander Ereskovsky
- IMBE, CNRS, IRD, Aix Marseille University, Station Marine d’Endoume, Rue de la Batterie des Lions, 13007 Marseille, France;
| | - Teofil Jesionowski
- Faculty of Chemical Technology, Institute of Chemical Technology and Engineering, Poznan University of Technology, Berdychowo 4, 60-965 Poznan, Poland
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Painter T, Ou C, Gong X, Xia CH. Longitudinal study of microphthalmia in connexin 50 knockout mice using spectral-domain optical coherence tomography. FRONTIERS IN OPHTHALMOLOGY 2024; 4:1387961. [PMID: 38984115 PMCID: PMC11182245 DOI: 10.3389/fopht.2024.1387961] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/19/2024] [Accepted: 04/15/2024] [Indexed: 07/11/2024]
Abstract
Connexin 50 (Cx50) mediated signaling is essential for controlling the lens growth and size. Cx50 mutations cause microphthalmia, smaller lenses, and cataracts in humans and animals. These ocular defects have never been investigated in live Cx50 mutant mice by using non-invasive imaging techniques. Here, we report a longitudinal study of the ocular defects in Cx50 knockout (Cx50KO) mice from the ages of 3 weeks to 12 months by using spectral-domain optical coherence tomography (SD-OCT). The anterior chamber depth (ACD), lens thickness (LT), vitreous chamber depth (VCD), and axial length (AL) were measured along the visual axis and adjusted with corresponding refractive indices. The SD-OCT image data confirm age-related reductions of LT and AL in live Cx50KO mice compared to age-matched wild-type (WT) controls, and the reduction values are comparable to the in vitro measurements of Cx50KO eyeballs and lenses reported previously. Moreover, reductions of ACD were observed in Cx50KO mice at all ages studied while VCD changes are statistically insignificant in comparison to the WT controls. Therefore, Cx50KO's microphthalmia with small lens is selectively associated with delayed ACD development but not the vitreous formation. This work supports the notion that lens size and/or growth is important for anterior chamber development.
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Affiliation(s)
| | | | | | - Chun-hong Xia
- Herbert Wertheim School of Optometry and Vision Science Program, University of California, Berkeley, Berkeley, CA, United States
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6
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Thakur A, Adiga S, Malhotra C, Sachdeva K, Singh S, Jain AK. Effect of decentration on the quality of vision in two aspheric posterior chamber intraocular lenses: A contralateral eye study. Indian J Ophthalmol 2024; 72:558-564. [PMID: 38189441 PMCID: PMC11149516 DOI: 10.4103/ijo.ijo_1639_23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Accepted: 09/14/2023] [Indexed: 01/09/2024] Open
Abstract
PURPOSE To perform an intraindividual comparison of the quality of vision and the effect of decentration between two aspheric intraocular lenses: aspheric balanced curve (ABC) design Vivinex iSert XY1 (Hoya Surgical Optics, Singapore) and anterior aspheric design Tecnis ZCB00 (Abbott Medical Optics, CA). SETTING Tertiary Eye Care Centre. DESIGN Prospective, randomized comparative study using a random number table. METHODS Thirty patients were randomized to the implantation of Vivinex iSert XY1 in one eye and Tecnis ZCB00 in the contralateral eye. Then, 12 weeks postoperatively, a laser ray-tracing aberrometer was used to evaluate the visual Strehl ratio, higher-order aberrations (HOA), decentration of IOL from the visual axis and geometric axis, angle alpha, and angle kappa. Contrast sensitivity was measured using the functional visual analyzer. RESULTS The visual internal Strehl ratio was higher ( P < 0.05) at all pupil sizes and the spherical aberrations values were lower ( P < 0.05) at larger pupil sizes (5 mm and 6 mm) in the Vivinex group. The mean decentration from the visual axis in the Vivinex group was significantly more than that in the Tecnis group ( P < 0.01). With an increase in angle alpha, there was a greater decline in the visual Strehl ratio for Tecnis; however, there was a statistically significant decline at 3 mm pupil size for Tecnis ZCB00 ( P = 0.028). The contrast sensitivity was similar for both IOLs. CONCLUSION In comparison to an anterior aspheric design IOL, the ABC design IOL yielded better quality of vision, neutralized spherical aberrations to a larger extent, and provided a relatively superior quality of vision with decentration.
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7
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Wang K, Pu Y, Chen L, Hoshino M, Uesugi K, Yagi N, Chen X, Usui Y, Hanashima A, Hashimoto K, Mohri S, Pierscionek BK. Optical development in the murine eye lens of accelerated senescence-prone SAMP8 and senescence-resistant SAMR1 strains. Exp Eye Res 2024; 241:109858. [PMID: 38467176 DOI: 10.1016/j.exer.2024.109858] [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: 01/07/2024] [Revised: 02/28/2024] [Accepted: 03/08/2024] [Indexed: 03/13/2024]
Abstract
The eye lens is responsible for focusing objects at various distances onto the retina and its refractive power is determined by its surface curvature as well as its internal gradient refractive index (GRIN). The lens continues to grow with age resulting in changes to the shape and to the GRIN profile. The present study aims to investigate how the ageing process may influence lens optical development. Murine lenses of accelerated senescence-prone strain (SAMP8) aged from 4 to 50 weeks; senescence-resistant strain (SAMR1) aged from 5 to 52 weeks as well as AKR strain (served as control) aged from 6 to 70 weeks were measured using the X-ray interferometer at the SPring-8 synchrotron Japan within three consecutive years from 2020 to 2022. Three dimensional distributions of the lens GRIN were reconstructed using the measured data and the lens shapes were determined using image segmentation in MatLab. Variations in the parameters describing the lens shape and the GRIN profile with age were compared amongst three mouse strains. With advancing age, both the lens anterior and posterior surface flattens and the lens sagittal thickness increase in all three mouse strains (Anterior radius of curvature increase at 0.008 mm/week, 0.007 mm/week and 0.002 mm/week while posterior radius of curvature increase at 0.002 mm/week, 0.007 mm/week and 0.003 mm/week respectively in AKR, SAMP8 and SAMR1 lenses). Compared with the AKR strain, the SAMP8 samples demonstrate a higher rate of increase in the posterior curvature radius (0.007 mm/week) and the thickness (0.015 mm/week), whilst the SAMR1 samples show slower increases in the anterior curvature radius (0.002 mm/week) and its thickness (0.013 mm/week). There are similar age-related trends in GRIN shape in the radial direction (in all three types of murine lenses nr2 and nr6 increase with age while nr4 decrease with age consistently) but not in the axial direction amongst three mouse strains (nz1 of AKR lens decrease while of SAMP8 and SAMR1 increase with age; nz2 of all three models increase with age; nz3 of AKR lens increase while of SAMP8 and SAMR1 decrease with age). The ageing process can influence the speed of lens shape change and affect the GRIN profile mainly in the axial direction, contributing to an accelerated decline rate of the optical power in the senescence-prone strain (3.5 D/week compared to 2.3 D/week in the AKR control model) but a retardatory decrease in the senescence-resistant strain (2.1 D/week compared to the 2.3D/week in the AKR control model).
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Affiliation(s)
- Kehao Wang
- School of Engineering Medicine and School of Biological Science and Medical Engineering, Beihang University, Beijing, China.
| | - Yutian Pu
- School of Engineering Medicine and School of Biological Science and Medical Engineering, Beihang University, Beijing, China.
| | - Leran Chen
- Peking University First Hospital, Beijing, China.
| | - Masato Hoshino
- Japan Synchrotron Radiation Research Institute (Spring-8), 1-1-1, Kouto, Sayo-cho, Sayo-gun, Hyogo, 679-5198, Japan.
| | - Kentaro Uesugi
- Japan Synchrotron Radiation Research Institute (Spring-8), 1-1-1, Kouto, Sayo-cho, Sayo-gun, Hyogo, 679-5198, Japan.
| | - Naoto Yagi
- Japan Synchrotron Radiation Research Institute (Spring-8), 1-1-1, Kouto, Sayo-cho, Sayo-gun, Hyogo, 679-5198, Japan.
| | - Xiaoyong Chen
- Department of Ophthalmology, Peking University Third Hospital, Beijing Key Laboratory of Restoration of Damaged Ocular Nerve, Peking University Third Hospital, China.
| | - Yuu Usui
- First Department of Physiology, Kawasaki Medical School, Kurashiki, Okayama, Japan.
| | - Akira Hanashima
- First Department of Physiology, Kawasaki Medical School, Kurashiki, Okayama, Japan.
| | - Ken Hashimoto
- First Department of Physiology, Kawasaki Medical School, Kurashiki, Okayama, Japan.
| | - Satoshi Mohri
- First Department of Physiology, Kawasaki Medical School, Kurashiki, Okayama, Japan.
| | - Barbara K Pierscionek
- Faculty of Health, Education, Medicine and Social Care, Medical Technology Research Centre, Anglia Ruskin University, Bishops Hall Lane, Chelmsford, United Kingdom.
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Islam ST, Cheheltani S, Cheng C, Fowler VM. Disease-related non-muscle myosin IIA D1424N rod domain mutation, but not R702C motor domain mutation, disrupts mouse ocular lens fiber cell alignment and hexagonal packing. Cytoskeleton (Hoboken) 2024:10.1002/cm.21853. [PMID: 38516850 PMCID: PMC11416570 DOI: 10.1002/cm.21853] [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: 01/01/2024] [Revised: 02/28/2024] [Accepted: 03/01/2024] [Indexed: 03/23/2024]
Abstract
The mouse ocular lens is an excellent vertebrate model system for studying hexagonal cell packing and shape changes during tissue morphogenesis and differentiation. The lens is composed of two types of cells, epithelial and fiber cells. During the initiation of fiber cell differentiation, lens epithelial cells transform from randomly packed cells to hexagonally shaped and packed cells to form meridional row cells. The meridional row cells further differentiate and elongate into newly formed fiber cells that maintain hexagonal cell shape and ordered packing. In other tissues, actomyosin contractility regulates cell hexagonal packing geometry during epithelial tissue morphogenesis. Here, we use the mouse lens as a model to study the effect of two human disease-related non-muscle myosin IIA (NMIIA) mutations on lens cellular organization during fiber cell morphogenesis and differentiation. We studied genetic knock-in heterozygous mice with NMIIA-R702C motor domain or NMIIA-D1424N rod domain mutations. We observed that while one allele of NMIIA-R702C has no impact on lens meridional row epithelial cell shape and packing, one allele of the NMIIA-D1424N mutation can cause localized defects in cell hexagonal packing. Similarly, one allele of NMIIA-R702C motor domain mutation does not affect lens fiber cell organization while the NMIIA-D1424N mutant proteins disrupt fiber cell organization and packing. Our work demonstrates that disease-related NMIIA rod domain mutations (D1424N or E1841K) disrupt mouse lens fiber cell morphogenesis and differentiation.
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Affiliation(s)
- Sadia T. Islam
- Department of Biological Sciences, University of Delaware, Newark, Delaware, USA
| | - Sepideh Cheheltani
- Department of Biological Sciences, University of Delaware, Newark, Delaware, USA
| | - Catherine Cheng
- School of Optometry and Vision Science Program, Indiana University, Bloomington, IN, United States
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, California, USA
| | - Velia M. Fowler
- Department of Biological Sciences, University of Delaware, Newark, Delaware, USA
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, California, USA
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Shaheen G, Paul J, Fleischman D. Macrophakia: The characterization of a novel lens condition. Heliyon 2024; 10:e25161. [PMID: 38322959 PMCID: PMC10844534 DOI: 10.1016/j.heliyon.2024.e25161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2023] [Revised: 01/07/2024] [Accepted: 01/22/2024] [Indexed: 02/08/2024] Open
Abstract
Purpose To present a novel characterization of a lens condition termed macrophakia which includes large or proportionally large lenses with shallow anterior chamber dimensions that are statistically deviant of a normal population. Observations We identified five eyes from three cases to have significantly large lens parameters and small anterior chamber depths. In all five eyes, the anterior chamber depth was less than 2 mm and the anterior chamber depth to lens thickness ratio was two standard deviations outside the normative range of lens and chamber measurements. These large lenses were all observed in the absence of typical pathology and other biometric abnormalities. Conclusions and importance A novel lens characterization termed macrophakia is proposed to describe large or proportionately large lenses. Naming this condition is clinically relevant and will enhance cataract evaluations and patient education.
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Affiliation(s)
- Gulrukh Shaheen
- Department of Ophthalmology, University of North Carolina, Chapel Hill, NC, USA
| | - Joshua Paul
- Department of Ophthalmology, University of North Carolina, Chapel Hill, NC, USA
| | - David Fleischman
- Department of Ophthalmology, University of North Carolina, Chapel Hill, NC, USA
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10
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Privado-Aroco A, Valdes-Soria G, Romaguera M, Serramito M, Carracedo G. Visual Quality Assessment and Comparison of Monofocal and Multifocal Scleral Lens Designs: A Pilot Study. Eye Contact Lens 2024; 50:35-40. [PMID: 38124285 DOI: 10.1097/icl.0000000000001046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/25/2023] [Indexed: 12/23/2023]
Abstract
PURPOSE To compare visual quality, contrast sensitivity, stereopsis, subjective vision, and comfort between monofocal and multifocal scleral lens (SL) designs. METHODS An experimental, cross over and short-term pilot study has been performed. Nineteen presbyopic patients (51.9±3.8 years) with regular corneas participated voluntarily in the study and Onefit MED monofocal and multifocal SL designs were fitted bilaterally. Subjective vision and comfort, contrast sensitivity function, stereopsis, high- and low-contrast visual acuity (VA) at 4 m and 40 cm under photopic and mesopic conditions, and defocus curves were measured. Data analysis was performed with nonparametric tests. P<0.05 was considered as statistically significant. RESULTS Mean addition power of the prescribed lenses was 1.72±0.38 diopters. Multifocal design showed a statistically significant improvement for intermediate and near vision in the defocus curve under photopic and mesopic conditions (P<0.05), however, worsening in stereopsis (P<0.05) and contrast sensitivity for high spatial frequencies (P<0.05). Distance visual acuity (VA) showed significantly lower values under mesopic conditions for high- and low-contrast tests (P<0.05), and on low-contrast test under photopic conditions (P<0.001) with the multifocal design. CONCLUSION Multifocal SLs showed better visual performance at intermediate and near distances without compromising distance vision under photopic conditions for a high-contrast test when compared with monofocal design.
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Affiliation(s)
- Ana Privado-Aroco
- Department of Optometry and Vision (A.P.-A., G.V.-S., M.R., M.S., G.C.), Faculty of Optics and Optometry, Complutense University of Madrid, Spain; and Ocupharm Research Group (A.P.-A., G.V.-S., M.R., M.S., G.C.), Faculty of Optics and Optometry, Complutense University of Madrid, Spain
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11
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Gupta A, Ruminski D, Villar AJ, Toledo RD, Gondek G, Pierscionek B, Artal P, Grulkowski I. Age-related changes in geometry and transparency of human crystalline lens revealed by optical signal discontinuity zones in swept-source OCT images. EYE AND VISION (LONDON, ENGLAND) 2023; 10:46. [PMID: 38037146 PMCID: PMC10691129 DOI: 10.1186/s40662-023-00365-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Accepted: 10/26/2023] [Indexed: 12/02/2023]
Abstract
BACKGROUND The shape and microstructure of the human crystalline lens alter with ageing, and this has an effect on the optical properties of the eye. The aim of this study was to characterise the age-related differences in the morphology and transparency of the eye lenses of healthy subjects through the optical signal discontinuity (OSD) zones in optical coherence tomography (OCT) images. We also investigated the association of those changes with the optical quality of the eye and visual function. METHODS OCT images of the anterior segment of 49 eyes of subjects (9-78 years) were acquired, and the OSD zones (nucleus, C1-C4 cortical zones) were identified. Central thickness, curvature and optical density were measured. The eye's optical quality was evaluated by the objective scatter index (OSI). Contrast sensitivity and visual acuity tests were performed. The correlation between extracted parameters and age was assessed. RESULTS The increase in lens thickness with age was dominated by the thickening of the cortical zone C3 (0.0146 mm/year). The curvature radii of the anterior lens surface and both anterior and posterior nucleo-cortical interfaces decreased with age (- 0.053 mm/year, - 0.013 mm/year and - 0.006 mm/year, respectively), and no change was observed for the posterior lens radius. OCT-based densitometry revealed significant correlations with age for all zones except for C1β, and the highest increase in density was in the C2-C4 zones (R = 0.45, 0.74, 0.56, respectively, P < 0.001). Increase in OSI was associated with the degradation of visual function. CONCLUSIONS OCT enables the identification of OSD zones of the crystalline lens. The most significant age-related changes occur in the C3 zone as it thickens with age at a faster rate and becomes more opaque than other OSD zones. The changes are associated with optical quality deterioration and reduction of visual performance. These findings contribute to a better understanding of the structure-function relationship of the ageing lens and offer insights into both pathological and aging alterations.
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Affiliation(s)
- Ashish Gupta
- Institute of Physics, Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University in Toruń, Grudziądzka 5, 87-100, Toruń, Poland
| | - Daniel Ruminski
- Institute of Physics, Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University in Toruń, Grudziądzka 5, 87-100, Toruń, Poland
| | - Alfonso Jimenez Villar
- Institute of Physics, Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University in Toruń, Grudziądzka 5, 87-100, Toruń, Poland
| | - Raúl Duarte Toledo
- Laboratorio de Óptica, Centro de Investigación en Óptica y Nanofísica, Universidad de Murcia, Edif. CIOyN, N º34, Campus de Espinardo, 30100, Murcia, Spain
| | - Grzegorz Gondek
- Institute of Physics, Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University in Toruń, Grudziądzka 5, 87-100, Toruń, Poland
| | - Barbara Pierscionek
- Faculty of Health, Education, Medicine, and Social Care, Medical Technology Research Center, Chelmsford Campus, Anglia Ruskin University, Bishop Hall Ln, Chelmsford, CM1 1SQ, UK
| | - Pablo Artal
- Laboratorio de Óptica, Centro de Investigación en Óptica y Nanofísica, Universidad de Murcia, Edif. CIOyN, N º34, Campus de Espinardo, 30100, Murcia, Spain
| | - Ireneusz Grulkowski
- Institute of Physics, Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University in Toruń, Grudziądzka 5, 87-100, Toruń, Poland.
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12
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Rodriguez J, Tan Q, Šikić H, Taber LA, Bassnett S. The effect of fibre cell remodelling on the power and optical quality of the lens. J R Soc Interface 2023; 20:20230316. [PMID: 37727073 PMCID: PMC10509584 DOI: 10.1098/rsif.2023.0316] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Accepted: 08/22/2023] [Indexed: 09/21/2023] Open
Abstract
Vertebrate eye lenses are uniquely adapted to form a refractive index gradient (GRIN) for improved acuity, and to grow slowly in size despite constant cell proliferation. The mechanisms behind these adaptations remain poorly understood. We hypothesize that cell compaction contributes to both. To test this notion, we examined the relationship between lens size and shape, refractive characteristics and the cross-sectional areas of constituent fibre cells in mice of different ages. We developed a block-face imaging method to visualize cellular cross sections and found that the cross-sectional areas of fibre cells rose and then decreased over time, with the most significant reduction occurring in denucleating cells in the adult lens cortex, followed by cells in the embryonic nucleus. These findings help reconcile differences between the predictions of lens growth models and empirical data. Biomechanical simulations suggested that compressive forces generated from continuous deposition of fibre cells could contribute to cellular compaction. However, optical measurements revealed that the GRIN did not mirror the pattern of cellular compaction, implying that compaction alone cannot account for GRIN formation and that additional mechanisms are likely to be involved.
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Affiliation(s)
- J. Rodriguez
- Department of Basic Sciences, University of Health Sciences and Pharmacy in St. Louis, 1 Pharmacy Place, St. Louis, MO 63110, USA
| | - Q. Tan
- Department of Ophthalmology & Visual Sciences, Washington University School of Medicine, 660 South Euclid Ave, Campus Box 8096, St. Louis, MO 63110, USA
| | - H. Šikić
- Department of Mathematics, Faculty of Science, University of Zagreb, Zagreb, Croatia
| | - L. A. Taber
- Department of Biomedical Engineering, Washington University, St. Louis, MO 63130, USA
| | - S. Bassnett
- Department of Ophthalmology & Visual Sciences, Washington University School of Medicine, 660 South Euclid Ave, Campus Box 8096, St. Louis, MO 63110, USA
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13
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Vu MP, Cheng C. Preparation and Immunofluorescence Staining of Bundles and Single Fiber Cells from the Cortex and Nucleus of the Eye Lens. J Vis Exp 2023:10.3791/65638. [PMID: 37358269 PMCID: PMC10729647 DOI: 10.3791/65638] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/27/2023] Open
Abstract
The lens is a transparent and ellipsoid organ in the anterior chamber of the eye that changes shape to finely focus light onto the retina to form a clear image. The bulk of this tissue comprises specialized, differentiated fiber cells that have a hexagonal cross section and extend from the anterior to the posterior poles of the lens. These long and skinny cells are tightly opposed to neighboring cells and have complex interdigitations along the length of the cell. The specialized interlocking structures are required for normal biomechanical properties of the lens and have been extensively described using electron microscopy techniques. This protocol demonstrates the first method to preserve and immunostain singular as well as bundles of mouse lens fiber cells to allow the detailed localization of proteins within these complexly shaped cells. The representative data show staining of the peripheral, differentiating, mature, and nuclear fiber cells across all regions of the lens. This method can potentially be used on fiber cells isolated from lenses of other species.
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Affiliation(s)
- Michael P Vu
- School of Optometry and Vision Science Program, Indiana University
| | - Catherine Cheng
- School of Optometry and Vision Science Program, Indiana University;
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14
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Pan X, Muir ER, Sellitto C, Wang K, Cheng C, Pierscionek B, Donaldson PJ, White TW. Age-Dependent Changes in the Water Content and Optical Power of the In Vivo Mouse Lens Revealed by Multi-Parametric MRI and Optical Modeling. Invest Ophthalmol Vis Sci 2023; 64:24. [PMID: 37079314 PMCID: PMC10132318 DOI: 10.1167/iovs.64.4.24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Accepted: 03/31/2023] [Indexed: 04/21/2023] Open
Abstract
Purpose The purpose of this study was to utilize in vivo magnetic resonance imaging (MRI) and optical modeling to investigate how changes in water transport, lens curvature, and gradient refractive index (GRIN) alter the power of the mouse lens as a function of age. Methods Lenses of male C57BL/6 wild-type mice aged between 3 weeks and 12 months (N = 4 mice per age group) were imaged using a 7T MRI scanner. Measurements of lens shape and the distribution of T2 (water-bound protein ratios) and T1 (free water content) values were extracted from MRI images. T2 values were converted into the refractive index (n) using an age-corrected calibration equation to calculate the GRIN at different ages. GRIN maps and shape parameters were inputted into an optical model to determine ageing effects on lens power and spherical aberration. Results The mouse lens showed two growth phases. From 3 weeks to 3 months, T2 decreased, GRIN increased, and T1 decreased. This was accompanied by increased lens thickness, volume, and surface radii of curvatures. The refractive power of the lens also increased significantly, and a negative spherical aberration was developed and maintained. Between 6 and 12 months of age, all physiological, geometrical, and optical parameters remained constant, although the lens continued to grow. Conclusions In the first 3 months, the mouse lens power increased as a result of changes in shape and in the GRIN, the latter driven by the decreased water content of the lens nucleus. Further research into the mechanisms regulating this decrease in mouse lens water could improve our understanding of how lens power changes during emmetropization in the developing human lens.
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Affiliation(s)
- Xingzheng Pan
- Department of Physiology, School of Medical Sciences, New Zealand Eye Centre, University of Auckland, New Zealand
| | - Eric R. Muir
- Department of Radiology, School of Medicine, Stony Brook University, Stony Brook, New York, United States
| | - Caterina Sellitto
- Department of Physiology & Biophysics, School of Medicine, Stony Brook University, Stony Brook, New York, United States
| | - Kehao Wang
- Beijing Advanced Innovation Centre for Biomedical Engineering, Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Engineering Medicine, Beihang University, Beijing, China
| | - Catherine Cheng
- School of Optometry and Vision Science Program, Indiana University, Bloomington, Indiana, United States
| | - Barbara Pierscionek
- Faculty of Health, Education, Medicine and Social Care, Medical Technology Research Centre, Anglia Ruskin University, Chelmsford Campus, United Kingdom
| | - Paul J. Donaldson
- Department of Physiology, School of Medical Sciences, New Zealand Eye Centre, University of Auckland, New Zealand
| | - Thomas W. White
- Department of Physiology & Biophysics, School of Medicine, Stony Brook University, Stony Brook, New York, United States
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15
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Islam ST, Cheng C, Parreno J, Fowler VM. Nonmuscle Myosin IIA Regulates the Precise Alignment of Hexagonal Eye Lens Epithelial Cells During Fiber Cell Formation and Differentiation. Invest Ophthalmol Vis Sci 2023; 64:20. [PMID: 37070941 PMCID: PMC10123325 DOI: 10.1167/iovs.64.4.20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Accepted: 03/27/2023] [Indexed: 04/19/2023] Open
Abstract
Purpose Epithelial cells in the equatorial region of the ocular lens undergo a remarkable transition from randomly packed cells into precisely aligned and hexagon-shaped cells organized into meridional rows. We investigated the function of nonmuscle myosin IIA (encoded by Myh9) in regulating equatorial epithelial cell alignment to form meridional rows during secondary fiber cell morphogenesis. Methods We used genetic knock-in mice to study a common human Myh9 mutation, E1841K, in the rod domain. The E1841K mutation disrupts bipolar filament assembly. Lens shape, clarity, and stiffness were evaluated, and Western blots were used to determine the level of normal and mutant myosins. Cryosections and lens whole mounts were stained and imaged by confocal microscopy to investigate cell shape and organization. Results We observed no obvious changes in lens size, shape, and biomechanical properties (stiffness and resilience) between the control and nonmuscle myosin IIA-E1841K mutant mice at 2 months of age. Surprisingly, we found misalignment and disorder of fiber cells in heterozygous and homozygous mutant lenses. Further analysis revealed misshapen equatorial epithelial cells that cause disorientation of the meridional rows before fiber cell differentiation in homozygous mutant lenses. Conclusions Our data indicate that nonmuscle myosin IIA bipolar filament assembly is required for the precise alignment of the meridional rows at the lens equator and that the organization of lens fiber cells depends on the proper patterning of meridional row epithelial cells. These data also suggest that lens fiber cell organization and a hexagonal shape are not required for normal lens size, shape transparency, or biomechanical properties.
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Affiliation(s)
- Sadia T. Islam
- Department of Biological Sciences, University of Delaware, Newark, Delaware, United States
| | - Catherine Cheng
- School of Optometry and Vision Science Program, Indiana University, Bloomington, Indiana, United States
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, California, United States
| | - Justin Parreno
- Department of Biological Sciences, University of Delaware, Newark, Delaware, United States
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, California, United States
| | - Velia M. Fowler
- Department of Biological Sciences, University of Delaware, Newark, Delaware, United States
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, California, United States
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16
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Mekonnen T, Zevallos-Delgado C, Zhang H, Singh M, Aglyamov SR, Larin KV. The lens capsule significantly affects the viscoelastic properties of the lens as quantified by optical coherence elastography. Front Bioeng Biotechnol 2023; 11:1134086. [PMID: 36970614 PMCID: PMC10034121 DOI: 10.3389/fbioe.2023.1134086] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Accepted: 02/21/2023] [Indexed: 03/11/2023] Open
Abstract
The crystalline lens is a transparent, biconvex structure that has its curvature and refractive power modulated to focus light onto the retina. This intrinsic morphological adjustment of the lens to fulfill changing visual demands is achieved by the coordinated interaction between the lens and its suspension system, which includes the lens capsule. Thus, characterizing the influence of the lens capsule on the whole lens’s biomechanical properties is important for understanding the physiological process of accommodation and early diagnosis and treatment of lenticular diseases. In this study, we assessed the viscoelastic properties of the lens using phase-sensitive optical coherence elastography (PhS-OCE) coupled with acoustic radiation force (ARF) excitation. The elastic wave propagation induced by ARF excitation, which was focused on the surface of the lens, was tracked with phase-sensitive optical coherence tomography. Experiments were conducted on eight freshly excised porcine lenses before and after the capsular bag was dissected away. Results showed that the group velocity of the surface elastic wave, V, in the lens with the capsule intact (V=2.55±0.23 m/s) was significantly higher (p < 0.001) than after the capsule was removed (V=1.19±0.25 m/s). Similarly, the viscoelastic assessment using a model that utilizes the dispersion of a surface wave showed that both Young’s modulus, E, and shear viscosity coefficient, η, of the encapsulated lens (E=8.14±1.10 kPa,η=0.89±0.093 Pa∙s) were significantly higher than that of the decapsulated lens (E=3.10±0.43 kPa,η=0.28±0.021 Pa∙s). These findings, together with the geometrical change upon removal of the capsule, indicate that the capsule plays a critical role in determining the viscoelastic properties of the crystalline lens.
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Affiliation(s)
- Taye Mekonnen
- Department of Biomedical Engineering, University of Houston, Houston, TX, United States
| | | | - Hongqiu Zhang
- Department of Biomedical Engineering, University of Houston, Houston, TX, United States
| | - Manmohan Singh
- Department of Biomedical Engineering, University of Houston, Houston, TX, United States
| | - Salavat R. Aglyamov
- Department of Mechanical Engineering, University of Houston, Houston, TX, United States
| | - Kirill V. Larin
- Department of Biomedical Engineering, University of Houston, Houston, TX, United States
- *Correspondence: Kirill V. Larin,
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17
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Abstract
Purpose: Presbyopia-the progressive loss of near focus with age-is primarily a result of changes in lens biomechanics. In particular, the shape of the ocular lens in the absence of zonular tension changes significantly throughout adulthood. Contributors to this change in shape are changes in lens biomechanical properties, continuous volumetric growth lens, and possibly remodeling of the lens capsule. Knowledge in this area is growing rapidly, so the purpose of this mini-review was to summarize and synthesize these gains.Methods: We review the recent literature in this field.Results: The mechanisms governing age-related changes in biomechanical properties remains unknown. We have recently shown that lens growth may be driven by zonular tension. The same mechanobiological mechanism driving lens growth may also lead to remodeling of the capsule, though this remains to be demonstrated.Conclusions: This mini-review focuses on identifying mechanisms which cause these age-related changes, suggesting future work which may elucidate these mechanisms, and briefly discusses ongoing efforts to develop a non-surgical approach for therapeutic management of presbyopia. We also propose a simple model linking lens growth and biomechanical properties.
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Affiliation(s)
- Wade Rich
- Department of Biomedical Engineering, The Ohio State University, Columbus, OH, USA
| | - Matthew A Reilly
- Department of Biomedical Engineering, The Ohio State University, Columbus, OH, USA.,Department of Ophthalmology & Visual Sciences, The Ohio State University, Columbus, OH, USA
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18
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Paidi SK, Zhang Q, Yang Y, Xia CH, Ji N, Gong X. Adaptive optical two-photon fluorescence microscopy probes cellular organization of ocular lenses in vivo. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.17.524320. [PMID: 36711806 PMCID: PMC9882239 DOI: 10.1101/2023.01.17.524320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The mammalian ocular lens is an avascular multicellular organ that grows continuously throughout life. Traditionally, its cellular organization is investigated using dissected lenses, which eliminates in vivo environmental and structural support. Here, we demonstrated that two-photon fluorescence microscopy (2PFM) can visualize lens cells in vivo. To maintain subcellular resolution at depth, we employed adaptive optics (AO) to correct aberrations due to ocular and lens tissues, which led to substantial signal and resolution improvements. Imaging lens cells up to 980 μm deep, we observed novel cellular organizations including suture-associated voids, enlarged vacuoles, and large cavities, contrary to the conventional view of a highly ordered organization. We tracked these features longitudinally over weeks and observed the incorporation of new cells during growth. Taken together, non-invasive longitudinal in vivo imaging of lens morphology using AO 2PFM will allow us to directly observe the development or alterations of lens cellular organization in living animals.
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Affiliation(s)
- Santosh Kumar Paidi
- School of Optometry, University of California, Berkeley, California 94720, USA
| | - Qinrong Zhang
- Department of Physics, University of California, Berkeley, California 94720, USA,Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720, USA
| | - Yuhan Yang
- Department of Physics, University of California, Berkeley, California 94720, USA
| | - Chun-Hong Xia
- School of Optometry, University of California, Berkeley, California 94720, USA,Vision Science Program, University of California, Berkeley, California 94720, USA
| | - Na Ji
- Department of Physics, University of California, Berkeley, California 94720, USA,Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720, USA,Helen Wills Neuroscience Institute, University of California, Berkeley, CA 94720, USA,Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA,Corresponding authors: Xiaohua Gong () and Na Ji ()
| | - Xiaohua Gong
- School of Optometry, University of California, Berkeley, California 94720, USA,Vision Science Program, University of California, Berkeley, California 94720, USA,Corresponding authors: Xiaohua Gong () and Na Ji ()
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19
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Regulation of lens water content: Effects on the physiological optics of the lens. Prog Retin Eye Res 2022:101152. [DOI: 10.1016/j.preteyeres.2022.101152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 11/21/2022] [Accepted: 11/22/2022] [Indexed: 12/09/2022]
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20
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Cvekl A, Camerino MJ. Generation of Lens Progenitor Cells and Lentoid Bodies from Pluripotent Stem Cells: Novel Tools for Human Lens Development and Ocular Disease Etiology. Cells 2022; 11:3516. [PMID: 36359912 PMCID: PMC9658148 DOI: 10.3390/cells11213516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 10/31/2022] [Accepted: 11/02/2022] [Indexed: 11/09/2022] Open
Abstract
In vitro differentiation of human pluripotent stem cells (hPSCs) into specialized tissues and organs represents a powerful approach to gain insight into those cellular and molecular mechanisms regulating human development. Although normal embryonic eye development is a complex process, generation of ocular organoids and specific ocular tissues from pluripotent stem cells has provided invaluable insights into the formation of lineage-committed progenitor cell populations, signal transduction pathways, and self-organization principles. This review provides a comprehensive summary of recent advances in generation of adenohypophyseal, olfactory, and lens placodes, lens progenitor cells and three-dimensional (3D) primitive lenses, "lentoid bodies", and "micro-lenses". These cells are produced alone or "community-grown" with other ocular tissues. Lentoid bodies/micro-lenses generated from human patients carrying mutations in crystallin genes demonstrate proof-of-principle that these cells are suitable for mechanistic studies of cataractogenesis. Taken together, current and emerging advanced in vitro differentiation methods pave the road to understand molecular mechanisms of cataract formation caused by the entire spectrum of mutations in DNA-binding regulatory genes, such as PAX6, SOX2, FOXE3, MAF, PITX3, and HSF4, individual crystallins, and other genes such as BFSP1, BFSP2, EPHA2, GJA3, GJA8, LIM2, MIP, and TDRD7 represented in human cataract patients.
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Affiliation(s)
- Aleš Cvekl
- Departments Ophthalmology and Visual Sciences, Albert Einstein College of Medicine, Bronx, NY 10461, USA
- Department of Genetics, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Michael John Camerino
- Departments Ophthalmology and Visual Sciences, Albert Einstein College of Medicine, Bronx, NY 10461, USA
- Department of Genetics, Albert Einstein College of Medicine, Bronx, NY 10461, USA
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21
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Lu A, Duan P, Xie J, Gao H, Chen M, Gong Y, Li J, Xu H. Recent progress and research trend of anti-cataract pharmacology therapy: A bibliometric analysis and literature review. Eur J Pharmacol 2022; 934:175299. [PMID: 36181780 DOI: 10.1016/j.ejphar.2022.175299] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Revised: 09/16/2022] [Accepted: 09/21/2022] [Indexed: 11/30/2022]
Abstract
Cataract is the leading cause of blindness worldwide. Cataract phacoemulsification combined with intraocular lens implantation causes great burden to global healthcare, especially for low- and middle-income countries. Such burden would be significantly relieved if cataracts can effectively be treated or delayed by non-surgical means. Excitingly, novel drugs have been developed to treat cataracts in recent decades. For example, oxysterols are found to be able to innovatively reverse lens clouding, novel nanotechnology-loaded drugs improve anti-cataract pharmacological effect, and traditional Chinese medicine demonstrates promising therapeutic effects against cataracts. In the present review, we performed bibliometric analysis to provide an overview perspective regarding the research status, hot topics, and academic trends in the field of anti-cataract pharmacology therapy. We further reviewed the curative effects and molecular mechanisms of anti-cataract drugs such as lanosterol, metformin, resveratrol and curcumin, and prospected the possibility of their clinical application in future.
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Affiliation(s)
- Ao Lu
- Southwest Hospital/Southwest Eye Hospital, Third Military Medical University (Army Medical University), Chongqing, China; Key Lab of Visual Damage and Regeneration & Restoration of Chongqing, Chongqing, China; The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Ophthalmology and Chongqing Eye Institute, Chongqing, China
| | - Ping Duan
- Southwest Hospital/Southwest Eye Hospital, Third Military Medical University (Army Medical University), Chongqing, China; Key Lab of Visual Damage and Regeneration & Restoration of Chongqing, Chongqing, China
| | - Jing Xie
- Southwest Hospital/Southwest Eye Hospital, Third Military Medical University (Army Medical University), Chongqing, China; Key Lab of Visual Damage and Regeneration & Restoration of Chongqing, Chongqing, China
| | - Hui Gao
- Southwest Hospital/Southwest Eye Hospital, Third Military Medical University (Army Medical University), Chongqing, China; Key Lab of Visual Damage and Regeneration & Restoration of Chongqing, Chongqing, China
| | - Mengmeng Chen
- Southwest Hospital/Southwest Eye Hospital, Third Military Medical University (Army Medical University), Chongqing, China; Key Lab of Visual Damage and Regeneration & Restoration of Chongqing, Chongqing, China
| | - Yu Gong
- Southwest Hospital/Southwest Eye Hospital, Third Military Medical University (Army Medical University), Chongqing, China; Key Lab of Visual Damage and Regeneration & Restoration of Chongqing, Chongqing, China
| | - Jiawen Li
- Department of Ophthalmology, University-Town Hospital of Chongqing Medical University, China.
| | - Haiwei Xu
- Southwest Hospital/Southwest Eye Hospital, Third Military Medical University (Army Medical University), Chongqing, China; Key Lab of Visual Damage and Regeneration & Restoration of Chongqing, Chongqing, China.
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22
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Yi Z, Jie G, Kai C, Jing S, Wei Z, Yun D. Theoretical derivation and clinical validation of the resolution limit of human eye to spherical lens change: a self-controlled study. Int Ophthalmol 2022; 43:1387-1394. [PMID: 36167944 PMCID: PMC10113289 DOI: 10.1007/s10792-022-02538-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Accepted: 09/15/2022] [Indexed: 11/30/2022]
Abstract
PURPOSE The aim of this study was to deduce theoretically and verify the resolution limit of human eye to spherical lens change for more reasonable design of the trial lenses. METHODS A total of 119 normal subjects with different myopia (not more than - 6D) were included. First, the resolution limit of discernible change in spherical power was derived based on the optical model. Then, the subjects were observed to see if they could perceive the changes in spherical power as per the resolution limit and compare the difference in the best-corrected visual acuity obtained with the resolution limit and interval of 0.25D. RESULTS Assuming that the cone cell diameter is 3 μm and the pupil diameter of 4 mm, the theoretically resolution limit was 0.05D. When the diopter of spherical power was increased, the ratios of ability to perceive 0.05D spherical lens change were 98.3% and 96.7% in right and left eyes. When the diopter of spherical power was decreased, the ratios of ability to perceive 0.05D spherical lens change were 78.9% and 83.2% in right and left eyes. The best-corrected visual acuity obtained with the 0.05 D interval trial lens was significantly better than in the 0.25 D interval on both eyes (Right eye - 0.04 ± 0.07 vs - 0.02 ± 0.06, p < 0.001; Left eye - 0.07 ± 0.06 vs - 0.04 ± 0.06, t = 8.825, p < 0.001). CONCLUSION The resolution limit of human eye to spherical lens change was about 0.05D and the better corrected visual acuity can be obtained by adjusting the spherical power at an interval of 0.05D. TRIAL REGISTRATION NUMBER ChiCTR2100047074. Date of registration: 2021/6/7.
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Affiliation(s)
- Zhen Yi
- National Engineering Research Center for Ophthalmology, Beijing Institute of Ophthalmology, Beijing Tongren Hospital, Capital Medical University, No. 1 Dongjiaominxiang, Beijing, 100730, Dongcheng, China.
| | - Gao Jie
- National Engineering Research Center for Ophthalmology, Beijing Institute of Ophthalmology, Beijing Tongren Hospital, Capital Medical University, No. 1 Dongjiaominxiang, Beijing, 100730, Dongcheng, China
| | - Cao Kai
- National Engineering Research Center for Ophthalmology, Beijing Institute of Ophthalmology, Beijing Tongren Hospital, Capital Medical University, No. 1 Dongjiaominxiang, Beijing, 100730, Dongcheng, China
| | - Shen Jing
- National Engineering Research Center for Ophthalmology, Beijing Institute of Ophthalmology, Beijing Tongren Hospital, Capital Medical University, No. 1 Dongjiaominxiang, Beijing, 100730, Dongcheng, China
| | - Zhang Wei
- National Engineering Research Center for Ophthalmology, Beijing Institute of Ophthalmology, Beijing Tongren Hospital, Capital Medical University, No. 1 Dongjiaominxiang, Beijing, 100730, Dongcheng, China
| | - Dai Yun
- Key Laboratory of Sichuan Province Ophthalmopathy Prevention & Cure and Visual Function Protection With TCM, Eye School of Chengdu University of TCM, Jinniu District, No. 8, Xinghui West Road, Chengdu, 610084, China
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23
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Parreno J, Emin G, Vu MP, Clark JT, Aryal S, Patel SD, Cheng C. Methodologies to unlock the molecular expression and cellular structure of ocular lens epithelial cells. Front Cell Dev Biol 2022; 10:983178. [PMID: 36176273 PMCID: PMC9514789 DOI: 10.3389/fcell.2022.983178] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Accepted: 08/16/2022] [Indexed: 01/25/2023] Open
Abstract
The transparent ocular lens in the anterior chamber of the eye is responsible for fine focusing of light onto the retina. The lens is entirely cellular with bulk of the tissue composed of fiber cells, and the anterior hemisphere of the lens is covered by a monolayer of epithelial cells. Lens epithelial cells are important for maintaining fiber cell homeostasis and for continual growth of the lens tissue throughout life. Cataracts, defined as any opacity in the lens, remain the leading cause of blindness in the world. Following cataract surgery, lens epithelial cells can undergo a process of epithelial-to-mesenchymal transition (EMT), leading to secondary cataracts due to posterior capsular opacification (PCO). Since the epithelial cells make up only a small fraction of the lens, specialized techniques are required to study lens epithelial cell biology and pathology. Studies using native lens epithelial cells often require pooling of samples to obtain enough cells to make sufficient samples for traditional molecular biology techniques. Here, we provide detailed protocols that enable the study of native mouse lens epithelial cells, including immunostaining of the native lens epithelium in flat mounts, extraction of RNA and proteins from pairs of lens epithelial monolayers, and isolation of lens epithelial cells for primary culture. These protocols will enable researchers to gain better insight on representative molecular expression and cellular structure of lens epithelial cells. We also provide comparative data between native, primary culture, and immortalized lens epithelial cells and discuss the advantages and disadvantages of each technique presented.
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Affiliation(s)
- Justin Parreno
- Department of Biological Sciences, University of Delaware, Newark, DE, United States
- Department of Biomedical Engineering, University of Delaware, Newark, DE, United States
- *Correspondence: Justin Parreno, ; Catherine Cheng,
| | - Grace Emin
- Department of Biological Sciences, University of Delaware, Newark, DE, United States
| | - Michael P. Vu
- School of Optometry and Vision Science Program, Indiana University, Bloomington, IN, United States
| | - Jackson T. Clark
- School of Optometry and Vision Science Program, Indiana University, Bloomington, IN, United States
| | - Sandeep Aryal
- Department of Biological Sciences, University of Delaware, Newark, DE, United States
- Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, United States
| | - Shaili D. Patel
- Department of Biological Sciences, University of Delaware, Newark, DE, United States
| | - Catherine Cheng
- School of Optometry and Vision Science Program, Indiana University, Bloomington, IN, United States
- *Correspondence: Justin Parreno, ; Catherine Cheng,
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24
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Wang K, Hoshino M, Uesugi K, Yagi N, Pierscionek BK, Andley UP. Oxysterol Compounds in Mouse Mutant αA- and αB-Crystallin Lenses Can Improve the Optical Properties of the Lens. Invest Ophthalmol Vis Sci 2022; 63:15. [PMID: 35575904 PMCID: PMC9123516 DOI: 10.1167/iovs.63.5.15] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Accepted: 04/22/2022] [Indexed: 11/24/2022] Open
Abstract
Purpose To investigate how cataract-linked mutations affect the gradient refractive index (GRIN) and lens opacification in mouse lenses and whether there is any effect on the optics of the lens from treatment with an oxysterol compound. Methods A total of 35 mice including wild-type and knock-in mutants (Cryaa-R49C and Cryab-R120G) were used in these experiments: 26 mice were treated with topical VP1-001, an oxysterol, in one eye and vehicle in the other, and nine mice were untreated controls. Slit lamp biomicroscopy was used to analyze the lens in live animals and to provide apparent cataract grades. Refractive index in the lenses of 64 unfixed whole mouse eyes was calculated from measurements with X-ray phase tomography based on X-ray Talbot interferometry with a synchrotron radiation source. Results Heterozygous Cryaa-R49C lenses had slightly irregularly shaped contours in the center of the GRIN and distinct disturbances of the gradient index at the anterior and posterior poles. Contours near the lens surface were denser in homozygous Cryab-R120G lenses. Treatment with topical VP1-001, an oxysterol, showed an improvement in refractive index profiles in 61% of lenses and this was supported by a reduction in apparent lens opacity grade by 1.0 in 46% of live mice. Conclusions These results indicate that α-crystallin mutations alter the refractive index gradient of mouse lenses in distinct ways and suggest that topical treatment with VP1-001 may improve lens transparency and refractive index contours in some lenses with mutations.
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Affiliation(s)
- Kehao Wang
- Beijing Advanced Innovation Centre for Biomedical Engineering, School of Engineering Medicine, Beihang University, Beijing, China
| | - Masato Hoshino
- Japan Synchrotron Radiation Research Institute (SPring8), Sayo, Hyogo, Japan
| | - Kentaro Uesugi
- Japan Synchrotron Radiation Research Institute (SPring8), Sayo, Hyogo, Japan
| | - Naoto Yagi
- Japan Synchrotron Radiation Research Institute (SPring8), Sayo, Hyogo, Japan
| | - Barbara K. Pierscionek
- Faculty of Health, Education, Medicine and Social Care, Medical Technology Research Centre, Anglia Ruskin University, Bishops Hall Lane, Chelmsford, United Kingdom
| | - Usha P. Andley
- Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO, United States
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25
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Allen A, Maddala R, Eldawy C, Rao PV. Mechanical Load and Piezo1 Channel Regulated Myosin II Activity in Mouse Lenses. Int J Mol Sci 2022; 23:4710. [PMID: 35563101 PMCID: PMC9105872 DOI: 10.3390/ijms23094710] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Revised: 04/13/2022] [Accepted: 04/19/2022] [Indexed: 02/01/2023] Open
Abstract
The cytoarchitecture and tensile characteristics of ocular lenses play a crucial role in maintaining their transparency and deformability, respectively, which are properties required for the light focusing function of ocular lens. Calcium-dependent myosin-II-regulated contractile characteristics and mechanosensitive ion channel activities are presumed to influence lens shape change and clarity. Here, we investigated the effects of load-induced force and the activity of Piezo channels on mouse lens myosin II activity. Expression of the Piezo1 channel was evident in the mouse lens based on immunoblot and immufluorescence analyses and with the use of a Piezo1-tdT transgenic mouse model. Under ex vivo conditions, change in lens shape induced by the load decreased myosin light chain (MLC) phosphorylation. While the activation of Piezo1 by Yoda1 for one hour led to an increase in the levels of phosphorylated MLC, Yoda1 treatment for an extended period led to opacification in association with increased calpain activity and degradation of membrane proteins in ex vivo mouse lenses. In contrast, inhibition of Piezo1 by GsMTx4 decreased MLC phosphorylation but did not affect the lens tensile properties. This exploratory study reveals a role for the mechanical load and Piezo1 channel activity in the regulation of myosin II activity in lens, which could be relevant to lens shape change during accommodation.
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Affiliation(s)
- Ariana Allen
- Department of Ophthalmology, Duke University School of Medicine, Durham, NC 27710, USA; (A.A.); (R.M.); (C.E.)
| | - Rupalatha Maddala
- Department of Ophthalmology, Duke University School of Medicine, Durham, NC 27710, USA; (A.A.); (R.M.); (C.E.)
| | - Camelia Eldawy
- Department of Ophthalmology, Duke University School of Medicine, Durham, NC 27710, USA; (A.A.); (R.M.); (C.E.)
| | - Ponugoti Vasantha Rao
- Department of Ophthalmology, Duke University School of Medicine, Durham, NC 27710, USA; (A.A.); (R.M.); (C.E.)
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC 27710, USA
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26
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Murugan S, Cheng C. Roles of Eph-Ephrin Signaling in the Eye Lens Cataractogenesis, Biomechanics, and Homeostasis. Front Cell Dev Biol 2022; 10:852236. [PMID: 35295853 PMCID: PMC8918484 DOI: 10.3389/fcell.2022.852236] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Accepted: 02/04/2022] [Indexed: 01/26/2023] Open
Abstract
The eye lens is responsible for fine focusing of light onto the retina, and its function relies on tissue transparency and biomechanical properties. Recent studies have demonstrated the importance of Eph-ephrin signaling for the maintenance of life-long lens homeostasis. The binding of Eph receptor tyrosine kinases to ephrin ligands leads to a bidirectional signaling pathway that controls many cellular processes. In particular, dysfunction of the receptor EphA2 or the ligand ephrin-A5 lead to a variety of congenital and age-related cataracts, defined as any opacity in the lens, in human patients. In addition, a wealth of animal studies reveal the unique and overlapping functions of EphA2 and ephrin-A5 in lens cell shape, cell organization and patterning, and overall tissue optical and biomechanical properties. Significant differences in lens phenotypes of mouse models with disrupted EphA2 or ephrin-A5 signaling indicate that genetic modifiers likely affect cataract phenotypes and progression, suggesting a possible reason for the variability of human cataracts due to Eph-ephrin dysfunction. This review summarizes the roles of EphA2 and ephrin-A5 in the lens and suggests future avenues of study.
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27
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Affiliation(s)
- Roy Quinlan
- Biomedical Sciences, Department of Biosciences, The University of Durham, Upper Mountjoy Science Site, Durham, DH1 3LE, UK.
| | - Frank Giblin
- Biomedical Sciences Emeritus, Eye Research Institute, Oakland University, Rochester, MI, 48309, USA.
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28
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Giannone AA, Li L, Sellitto C, White TW. Physiological Mechanisms Regulating Lens Transport. Front Physiol 2022; 12:818649. [PMID: 35002784 PMCID: PMC8735835 DOI: 10.3389/fphys.2021.818649] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Accepted: 12/10/2021] [Indexed: 12/02/2022] Open
Abstract
The transparency and refractive properties of the lens are maintained by the cellular physiology provided by an internal microcirculation system that utilizes spatial differences in ion channels, transporters and gap junctions to establish standing electrochemical and hydrostatic pressure gradients that drive the transport of ions, water and nutrients through this avascular tissue. Aging has negative effects on lens transport, degrading ion and water homeostasis, and producing changes in lens water content. This alters the properties of the lens, causing changes in optical quality and accommodative amplitude that initially result in presbyopia in middle age and ultimately manifest as cataract in the elderly. Recent advances have highlighted that the lens hydrostatic pressure gradient responds to tension transmitted to the lens through the Zonules of Zinn through a mechanism utilizing mechanosensitive channels, multiple sodium transporters respond to changes in hydrostatic pressure to restore equilibrium, and that connexin hemichannels and diverse intracellular signaling cascades play a critical role in these responses. The mechanistic insight gained from these studies has advanced our understanding of lens transport and how it responds and adapts to different inputs both from within the lens, and from surrounding ocular structures.
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Affiliation(s)
- Adrienne A Giannone
- Master of Science Program, Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY, United States
| | - Leping Li
- Department of Physiology and Biophysics, School of Medicine, Stony Brook University, Stony Brook, NY, United States
| | - Caterina Sellitto
- Department of Physiology and Biophysics, School of Medicine, Stony Brook University, Stony Brook, NY, United States
| | - Thomas W White
- Department of Physiology and Biophysics, School of Medicine, Stony Brook University, Stony Brook, NY, United States
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29
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Cheng C, Wang K, Hoshino M, Uesugi K, Yagi N, Pierscionek B. EphA2 Affects Development of the Eye Lens Nucleus and the Gradient of Refractive Index. Invest Ophthalmol Vis Sci 2022; 63:2. [PMID: 34978559 PMCID: PMC8742528 DOI: 10.1167/iovs.63.1.2] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Purpose Our studies in mouse eye lenses demonstrate that ephrin-A5 and EphA2 are needed for normal epithelial cells and lens transparency. We sought to determine whether EphA2 and ephrin-A5 are important for lens morphometrics, nucleus formation, and refractive index. Methods We performed tissue morphometric measurements, electron microscopy, Western blots, and interferometric measurements using an X-ray synchrotron beam source to measure the gradient of refractive index (GRIN) to compare mouse lenses with genetic disruption of EphA2 or ephrin-A5. Results Morphometric analysis revealed that although there is no change in the overall lens volume, there is a change in lens shape in both EphA2-/- lenses and ephrin-A5-/- lenses. Surprisingly, EphA2-/- lenses had small and soft lens nuclei different from hard lens nuclei of control lenses. SEM images revealed changes in cell morphology of EphA2-/- fiber cells close to the center of the lens. Inner EphA2-/- lens fibers had more pronounced tongue-and-groove interdigitations and formed globular membrane morphology only in the deepest layers of the lens nucleus. We did not observe nuclear defects in ephrin-A5-/- lenses. There was an overall decrease in magnitude of refractive index across EphA2-/- lenses, which is most pronounced in the nucleus. Conclusions This work reveals that Eph-ephrin signaling plays a role in fiber cell maturation, nuclear compaction, and lens shape. Loss of EphA2 disrupts the nuclear compaction resulting in a small lens nucleus. Our data suggest that Eph-ephrin signaling may be required for fiber cell membrane reorganization and compaction and for establishing a normal GRIN.
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Affiliation(s)
- Catherine Cheng
- School of Optometry, Indiana University, Bloomington, IN, United States
| | - Kehao Wang
- Beijing Advanced Innovation Centre for Biomedical Engineering, Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Engineering Medicine, Beihang University, Beijing, China
| | - Masato Hoshino
- Japan Synchrotron Radiation Research Institute (Spring-8), 1-1-1, Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5198 Japan
| | - Kentaro Uesugi
- Japan Synchrotron Radiation Research Institute (Spring-8), 1-1-1, Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5198 Japan
| | - Naoto Yagi
- Japan Synchrotron Radiation Research Institute (Spring-8), 1-1-1, Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5198 Japan
| | - Barbara Pierscionek
- Faculty of Health, Education, Medicine and Social Care, Medical Technology Research Centre, Anglia Ruskin University, Chelmsford Campus, United Kingdom
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30
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Ruiss M, Kronschläger M, Schlatter A, Dechat T, Findl O. Comparison of methods to experimentally induce opacification and elasticity change in ex vivo porcine lenses. Sci Rep 2021; 11:23406. [PMID: 34862438 PMCID: PMC8642470 DOI: 10.1038/s41598-021-02851-6] [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] [Received: 05/19/2021] [Accepted: 11/22/2021] [Indexed: 11/17/2022] Open
Abstract
At the moment, cataract, which is the opacification of the eye's lens, can only be treated by surgery. In order to develop and test new pharmacological treatment strategies for the disease, there is a need for an appropriate in vitro model using ex vivo animal lenses. In this study, porcine lenses were incubated in either culture medium, glucose, triamcinolone acetonide, sodium chloride, hydrogen peroxide, sodium selenite, neutral buffered formalin, or were exposed to microwave heating to experimentally induce lens opacification. Changes in the lens morphology, weight, size, and elasticity were monitored 7 days after treatment. The fastest induction of dense opacification was seen in lenses exposed to sodium chloride, neutral buffered formalin, and microwave heating. No change in the size and weight of the lenses were detected, whereas loss in elasticity could be detected in lenses treated with formalin solution or microwave heating. Thus, neutral buffered formalin- and microwave-treated ex vivo porcine lenses seem to be a suitable model for mature cataracts, whereas hypertonic sodium chloride may be useful for studies on osmolarity-induced lens opacification.
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Affiliation(s)
- Manuel Ruiss
- Department of Ophthalmology, Hanusch Hospital, Vienna Institute for Research in Ocular Surgery (VIROS), a Karl Landsteiner Institute, Heinrich-Collin-Straße 30, 1140, Vienna, Austria
| | - Martin Kronschläger
- Department of Ophthalmology, Hanusch Hospital, Vienna Institute for Research in Ocular Surgery (VIROS), a Karl Landsteiner Institute, Heinrich-Collin-Straße 30, 1140, Vienna, Austria.
| | - Andreas Schlatter
- Department of Ophthalmology, Hanusch Hospital, Vienna Institute for Research in Ocular Surgery (VIROS), a Karl Landsteiner Institute, Heinrich-Collin-Straße 30, 1140, Vienna, Austria
| | - Thomas Dechat
- 1st Medical Department, Hanusch Hospital, Ludwig Boltzmann Institute of Osteology at Hanusch Hospital of OEGK and AUVA Trauma Centre Meidling, 1140, Vienna, Austria
| | - Oliver Findl
- Department of Ophthalmology, Hanusch Hospital, Vienna Institute for Research in Ocular Surgery (VIROS), a Karl Landsteiner Institute, Heinrich-Collin-Straße 30, 1140, Vienna, Austria
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31
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Rowan S, Jiang S, Francisco SG, Pomatto LCD, Ma Z, Jiao X, Campos MM, Aryal S, Patel SD, Mahaling B, Riazuddin SA, Duh EJ, Lachke SA, Hejtmancik JF, de Cabo R, FitzGerald PG, Taylor A. Aged Nrf2-Null Mice Develop All Major Types of Age-Related Cataracts. Invest Ophthalmol Vis Sci 2021; 62:10. [PMID: 34882206 PMCID: PMC8665303 DOI: 10.1167/iovs.62.15.10] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Purpose Age-related cataracts affect the majority of older adults and are a leading cause of blindness worldwide. Treatments that delay cataract onset or severity have the potential to delay cataract surgery, but require relevant animal models that recapitulate the major types of cataracts for their development. Unfortunately, few such models are available. Here, we report the lens phenotypes of aged mice lacking the critical antioxidant transcription factor Nfe2l2 (designated as Nrf2 −/−). Methods Three independent cohorts of Nrf2 −/− and wild-type C57BL/6J mice were evaluated for cataracts using combinations of slit lamp imaging, photography of freshly dissected lenses, and histology. Mice were fed high glycemic diets, low glycemic diets, regular chow ad libitum, or regular chow with 30% caloric restriction. Results Nrf2 −/− mice developed significant opacities between 11 and 15 months and developed advanced cortical, posterior subcapsular, anterior subcapsular, and nuclear cataracts. Cataracts occurred similarly in male mice fed high or low glycemic diets, and were also observed in 21-month male and female Nrf2 −/− mice fed ad libitum or 30% caloric restriction. Histological observation of 18-month cataractous lenses revealed significant disruption to fiber cell architecture and the retention of nuclei throughout the cortical region of the lens. However, fiber cell denucleation and initiation of lens differentiation was normal at birth, with the first abnormalities observed at 3 months. Conclusions Nrf2 −/− mice offer a tool to understand how defective antioxidant signaling causes multiple forms of cataract and may be useful for screening drugs to prevent or delay cataractogenesis in susceptible adults.
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Affiliation(s)
- Sheldon Rowan
- JM-USDA Human Nutrition Research Center on Aging, Tufts University, Boston, Massachusetts, United States.,Department of Ophthalmology, Tufts University School of Medicine, Tufts University, Boston, Massachusetts, United States.,Friedman School of Nutrition Science and Policy, Tufts University, Boston, Massachusetts, United States
| | - Shuhong Jiang
- JM-USDA Human Nutrition Research Center on Aging, Tufts University, Boston, Massachusetts, United States
| | - Sarah G Francisco
- JM-USDA Human Nutrition Research Center on Aging, Tufts University, Boston, Massachusetts, United States
| | - Laura C D Pomatto
- Translational Gerontology Branch, National Institute on Aging, National Institute of Health, Baltimore, Maryland, United States
| | - Zhiwei Ma
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States
| | - Xiaodong Jiao
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States
| | - Maria M Campos
- NEI Histology Core, National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States
| | - Sandeep Aryal
- Department of Biological Sciences, University of Delaware, Newark, Delaware, United States
| | - Shaili D Patel
- Department of Biological Sciences, University of Delaware, Newark, Delaware, United States
| | - Binapani Mahaling
- Department of Ophthalmology, The Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States
| | - S Amer Riazuddin
- Department of Ophthalmology, The Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States
| | - Elia J Duh
- Department of Ophthalmology, The Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States
| | - Salil A Lachke
- Department of Biological Sciences, University of Delaware, Newark, Delaware, United States.,Center for Bioinformatics and Computational Biology, University of Delaware, Newark, Delaware, United States
| | - J Fielding Hejtmancik
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States
| | - Rafael de Cabo
- Translational Gerontology Branch, National Institute on Aging, National Institute of Health, Baltimore, Maryland, United States
| | - Paul G FitzGerald
- Department of Cell Biology and Human Anatomy, School of Medicine, University of California Davis, Davis, California, United States
| | - Allen Taylor
- JM-USDA Human Nutrition Research Center on Aging, Tufts University, Boston, Massachusetts, United States.,Department of Ophthalmology, Tufts University School of Medicine, Tufts University, Boston, Massachusetts, United States.,Friedman School of Nutrition Science and Policy, Tufts University, Boston, Massachusetts, United States
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32
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Cheng C. EphA2 and Ephrin-A5 Guide Eye Lens Suture Alignment and Influence Whole Lens Resilience. Invest Ophthalmol Vis Sci 2021; 62:3. [PMID: 34854885 PMCID: PMC8648058 DOI: 10.1167/iovs.62.15.3] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose Fine focusing of light by the eye lens onto the retina relies on the ability of the lens to change shape during the process of accommodation. Little is known about the cellular structures that regulate elasticity and resilience. We tested whether Eph–ephrin signaling is involved in lens biomechanical properties. Methods We used confocal microscopy and tissue mechanical testing to examine mouse lenses with genetic disruption of EphA2 or ephrin-A5. Results Confocal imaging revealed misalignment of the suture between each shell of newly added fiber cells in knockout lenses. Despite having disordered sutures, loss of EphA2 or ephrin-A5 did not affect lens stiffness. Surprisingly, knockout lenses were more resilient and recovered almost completely after load removal. Confocal microscopy and quantitative image analysis from live lenses before, during, and after compression revealed that knockout lenses had misaligned Y-sutures, leading to a change in force distribution during compression. Knockout lenses displayed decreased separation of fiber cell tips at the anterior suture at high loads and had more complete recovery after load removal, which leads to improved whole-lens resiliency. Conclusions EphA2 and ephrin-A5 are needed for normal patterning of fiber cell tips and the formation of a well-aligned Y-suture with fiber tips stacked on top of previous generations of fiber cells. The misalignment of lens sutures leads to increased resilience after compression. The data suggest that alignment of the Y-suture may constrain the overall elasticity and resilience of the lens.
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Affiliation(s)
- Catherine Cheng
- School of Optometry and Vision Science Program, Indiana University, Bloomington, Indiana, United States
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33
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Stopka W, Libby T, Lin S, Wang E, Xia CH, Gong X. Age-related changes of lens stiffness in wild-type and Cx46 knockout mice. Exp Eye Res 2021; 212:108777. [PMID: 34597677 PMCID: PMC10054276 DOI: 10.1016/j.exer.2021.108777] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 09/21/2021] [Accepted: 09/23/2021] [Indexed: 10/20/2022]
Abstract
We have investigated how connexin 46 (Cx46) regulates lens stiffness by studying different Cx46 knockout (Cx46KO) mice. A modified muscle lever system was used to determine the lens stiffness of wild-type (WT) and Cx46KO mice at the C57BL/6J (B6) and the 129SvJae (129) strain backgrounds according to total lens displacement at the point of maximum force when fresh lenses were compressed with a maximum of 2 mN of force. In comparison to B6-WT controls, young and old B6-Cx46KO lenses showed 23% and 28% reductions in lens displacement, respectively. Comparing to 129-WT controls, old 129-Cx46KO lenses showed 50% reduction in the lens displacement while young 129-Cx46KO lenses displayed similar displacement. Old B6-Cx46KO and old 129-Cx46KO lenses showed almost identical lens displacement, 128 μm versus 127 μm. Morphological data revealed unique changes of peripheral fiber cell shapes in young B6-WT lenses but not in young B6-Cx46KO, 129-WT and 129-Cx46KO lenses. This work reveals Cx46 deletion increases the lens stiffness in both young and old mice at B6 strain background but only in old mice at 129 strain background which contains intermediate filament CP49 gene deletion. Cx46 impairment increases old mouse lens stiffness and may contribute to the development of presbyopia.
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Affiliation(s)
- Wiktor Stopka
- UC Berkeley - UCSF Graduate Program in Bioengineering, University of California, Berkeley, CA, USA
| | - Tom Libby
- Center for Biological Inspiration in Education and Research (CiBER), University of California, Berkeley, CA, USA
| | - Stephanie Lin
- School of Optometry and Vision Science Program, University of California, Berkeley, CA, USA
| | - Eddie Wang
- School of Optometry and Vision Science Program, University of California, Berkeley, CA, USA
| | - Chun-Hong Xia
- School of Optometry and Vision Science Program, University of California, Berkeley, CA, USA
| | - Xiaohua Gong
- UC Berkeley - UCSF Graduate Program in Bioengineering, University of California, Berkeley, CA, USA; School of Optometry and Vision Science Program, University of California, Berkeley, CA, USA.
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34
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Holmgren CD, Stahr P, Wallace DJ, Voit KM, Matheson EJ, Sawinski J, Bassetto G, Kerr JND. Visual pursuit behavior in mice maintains the pursued prey on the retinal region with least optic flow. eLife 2021; 10:e70838. [PMID: 34698633 PMCID: PMC8547958 DOI: 10.7554/elife.70838] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Accepted: 09/30/2021] [Indexed: 11/26/2022] Open
Abstract
Mice have a large visual field that is constantly stabilized by vestibular ocular reflex (VOR) driven eye rotations that counter head-rotations. While maintaining their extensive visual coverage is advantageous for predator detection, mice also track and capture prey using vision. However, in the freely moving animal quantifying object location in the field of view is challenging. Here, we developed a method to digitally reconstruct and quantify the visual scene of freely moving mice performing a visually based prey capture task. By isolating the visual sense and combining a mouse eye optic model with the head and eye rotations, the detailed reconstruction of the digital environment and retinal features were projected onto the corneal surface for comparison, and updated throughout the behavior. By quantifying the spatial location of objects in the visual scene and their motion throughout the behavior, we show that the prey image consistently falls within a small area of the VOR-stabilized visual field. This functional focus coincides with the region of minimal optic flow within the visual field and consequently area of minimal motion-induced image-blur, as during pursuit mice ran directly toward the prey. The functional focus lies in the upper-temporal part of the retina and coincides with the reported high density-region of Alpha-ON sustained retinal ganglion cells.
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Affiliation(s)
- Carl D Holmgren
- Department of Behavior and Brain Organization, Research center caesarBonnGermany
| | - Paul Stahr
- Department of Behavior and Brain Organization, Research center caesarBonnGermany
| | - Damian J Wallace
- Department of Behavior and Brain Organization, Research center caesarBonnGermany
| | - Kay-Michael Voit
- Department of Behavior and Brain Organization, Research center caesarBonnGermany
| | - Emily J Matheson
- Department of Behavior and Brain Organization, Research center caesarBonnGermany
| | - Juergen Sawinski
- Department of Behavior and Brain Organization, Research center caesarBonnGermany
| | - Giacomo Bassetto
- Department of Behavior and Brain Organization, Research center caesarBonnGermany
- Machine Learning in Science, Eberhard Karls University of TübingenTübingenGermany
| | - Jason ND Kerr
- Department of Behavior and Brain Organization, Research center caesarBonnGermany
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Batchelor WM, Heilman BM, Arrieta-Quintero E, Ruggeri M, Parel JM, Manns F, Cabrera-Ghayouri S, Dibas M, Ziebarth NM. Measuring the effects of postmortem time and age on mouse lens elasticity using atomic force microscopy. Exp Eye Res 2021; 212:108768. [PMID: 34534541 DOI: 10.1016/j.exer.2021.108768] [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] [Received: 06/02/2021] [Revised: 09/09/2021] [Accepted: 09/12/2021] [Indexed: 11/25/2022]
Abstract
The mouse lens is frequently used both in vivo and ex vivo in ophthalmic research to model conditions affecting the human lens, such as presbyopia. The mouse lens has a delicate structure which is prone to damage and biomechanical changes both before and after extraction from the whole globe. When not properly controlled for, these changes can confound the biomechanical analysis of mouse lenses. In this study, atomic force microscopy microindentation was used to assess changes in the Young's Modulus of Elasticity of the mouse lens as a function of mouse age and postmortem time. Old mouse lenses measured immediately postmortem were significantly stiffer than young mouse lenses (p = 0.028). However, after 18 h of incubation, there was no measurable difference in lens stiffness between old and young mouse lenses (p = 0.997). This demonstrates the need for careful experimental control in experiments using the mouse lens, especially regarding postmortem time.
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Affiliation(s)
- Wyndham More Batchelor
- Biomedical Atomic Force Microscopy Laboratory, Department of Biomedical Engineering, University of Miami College of Engineering, Miami, FL, USA
| | - Bianca Maceo Heilman
- Biomedical Atomic Force Microscopy Laboratory, Department of Biomedical Engineering, University of Miami College of Engineering, Miami, FL, USA; Ophthalmic Biophysics Center, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Esdras Arrieta-Quintero
- Ophthalmic Biophysics Center, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Marco Ruggeri
- Ophthalmic Biophysics Center, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Jean-Marie Parel
- Biomedical Atomic Force Microscopy Laboratory, Department of Biomedical Engineering, University of Miami College of Engineering, Miami, FL, USA; Ophthalmic Biophysics Center, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, USA; Brien Holden Vision Institute, University of New South Wales, Sydney, Australia
| | - Fabrice Manns
- Biomedical Atomic Force Microscopy Laboratory, Department of Biomedical Engineering, University of Miami College of Engineering, Miami, FL, USA; Ophthalmic Biophysics Center, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, USA
| | | | | | - Noel Marysa Ziebarth
- Biomedical Atomic Force Microscopy Laboratory, Department of Biomedical Engineering, University of Miami College of Engineering, Miami, FL, USA.
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36
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Patel SD, Aryal S, Mennetti LP, Parreno J. Whole mount staining of lenses for visualization of lens epithelial cell proteins. MethodsX 2021; 8:101376. [PMID: 34430272 PMCID: PMC8374519 DOI: 10.1016/j.mex.2021.101376] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Accepted: 04/26/2021] [Indexed: 11/17/2022] Open
Abstract
Whole mount imaging of the lens allows for high spatial resolution visualization of lens epithelial structures by using small molecule fluorescent probes. However, the visualization of specific proteins in lens epithelial cells within whole lenses remains a challenge as the capsule that surrounds the lens does not allow penetration of antibodies. Here we describe a whole mount imaging method that allows us to overcome this challenge by digesting the lens capsules of paraformaldehyde fixed lenses using collagenase. This method enables the penetration of antibodies for effective visualization of proteins in the epithelium of whole lenses.A limitation to lens whole mount imaging is the ability to visualize specific proteins as the collagen capsule surrounding the lens impedes the penetration of antibodies This protocol helps overcome this limitation by a light collagenase digestion of the capsule of fixed lenses prior to immunostaining This method allows for the imaging of specific proteins in the epithelium of the whole lens tissue
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Affiliation(s)
- Shaili D Patel
- Department of Biological Sciences, University of Delaware USA
| | - Sandeep Aryal
- Department of Biological Sciences, University of Delaware USA
| | | | - Justin Parreno
- Department of Biological Sciences, University of Delaware USA
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37
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Martis RM, Li B, Donaldson PJ, Lim JCH. Early Onset of Age-Related Cataracts in Cystine/Glutamate Antiporter Knockout Mice. Invest Ophthalmol Vis Sci 2021; 62:23. [PMID: 34156426 PMCID: PMC8237109 DOI: 10.1167/iovs.62.7.23] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Purpose The purpose of this study was to determine the importance of the xCT is a subunit. The cystine/glutamate antiporter is actually system xc-xCT subunit of the cystine/glutamate antiporter in maintaining redox balance by investigating the effects of the loss of xCT on lens transparency and cystine/cysteine balance in the aqueous humour. Methods C57Bl/6 wild-type and xCT knockout mice at five age groups (6 weeks to 12 months) were used. Lens transparency was examined using a slit-lamp and morphological changes visualized by immunolabelling and confocal microscopy. Quantification of glutathione in lenses and cysteine and cystine levels in the aqueous was conducted by liquid chromatography tandem mass spectrometry (LC-MS/MS). Results Slit-lamp examinations revealed that 3-month-old wild-type mice and xCT knockout mice lenses exhibited an anterior localized cataract. The frequency of this cataract significantly increased in the knockout mice compared to the wild-type mice. Morphological studies revealed a localized swelling of the lens fiber cells at the anterior pole. Glutathione levels in whole lenses were similar between wild-type and knockout mice. However, glutathione levels were significantly decreased at 3 months in the knockout mice in the lens epithelium compared to the wild-type mice. Aqueous cysteine levels remained similar between wild-type and knockout mice at all age groups, whereas cystine levels were significantly increased in 3-, 9-, and 12-month-old knockout mice compared to wild-type mice. Conclusions Loss of xCT resulted in the depletion of glutathione in the epithelium and an oxidative shift in the cysteine/cystine ratio of the aqueous. Together, these oxidative changes may contribute to the accelerated development of an anterior cataract in knockout mice, which appears to be a normal feature of aging in wild-type mice.
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Affiliation(s)
- Renita Maria Martis
- Department of Physiology, School of Medical Sciences, University of Auckland, Auckland, New Zealand.,New Zealand National Eye Centre, University of Auckland, Auckland, New Zealand
| | - Bo Li
- Department of Physiology, School of Medical Sciences, University of Auckland, Auckland, New Zealand.,New Zealand National Eye Centre, University of Auckland, Auckland, New Zealand
| | - Paul James Donaldson
- Department of Physiology, School of Medical Sciences, University of Auckland, Auckland, New Zealand.,New Zealand National Eye Centre, University of Auckland, Auckland, New Zealand
| | - Julie Ching-Hsia Lim
- Department of Physiology, School of Medical Sciences, University of Auckland, Auckland, New Zealand.,New Zealand National Eye Centre, University of Auckland, Auckland, New Zealand
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38
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Zhou HY, Yan H, Yan WJ, Wang XC. Ultrasound elastography for evaluating stiffness of the human lens nucleus with aging: a feasibility study. Int J Ophthalmol 2021; 14:240-244. [PMID: 33614452 DOI: 10.18240/ijo.2021.02.09] [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: 11/07/2019] [Accepted: 04/21/2020] [Indexed: 11/23/2022] Open
Abstract
AIM To investigate the significance of ultrasound elastography for evaluating stiffness of the human lens nucleus in volunteers with different ages. METHODS A total of 90 volunteers (lens transparency, uncorrected visual acuity ≥0.5, intraocular pressure: 14-19 mm Hg) were divided into 3 groups according to age: Group A (30 people, median age: 82±3.5y, mean axial lengths 23.7±0.5 mm); Group B (30 people, median age: 46±2.1y, mean axial lengths 23.9±0.4 mm); and Group C (30 people, median age: 22±3.5y, mean axial lengths 24.0±0.4 mm). Lens nuclear stiffness was measured by Free-hand qualitative elastography by independent operators. Strain gray scale and color-coded elastography maps were recorded. In each case, three consecutive detections were performed and strain ratio was used for statistical analysis. RESULTS Elastography analysis showed excellent diagnostic performance for lens sclerosis. Lens strain ratio was lowest (0.03±0.01)% in Group A and highest (2.03±0.43)% in Group C. Lens strain ratio was moderate (0.64±0.10)% in Group B. There were significant differences between these three groups (P<0.05). The lens nucleus strain rate changes with age. With aging, the lens nucleus strain rate and resilience decrease, demonstrating harder texture. CONCLUSION The relationship between human lens stiffness and age is demonstrated by ultrasound elastography. Older age is associated with lower strain ratio and less resilience of the lens.
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Affiliation(s)
- Hai-Yan Zhou
- Department of Ophthalmology, Shaanxi Provincial People's Hospital, Third Affiliated Hospital of the School of Medicine, Xi'an Jiaotong University, Xi'an 710068, Shaanxi Province, China
| | - Hong Yan
- Department of Ophthalmology, Xi'an No.4 Hospital, Shaanxi Eye Hospital, Affiliated Guangren Hospital School of Medicine, Xi'an Jiaotong University, Xi'an 710004, Shaanxi Province, China
| | - Wei-Jia Yan
- Medical School, the University of Sheffield, Western Bank, Sheffield S10 2TN, UK
| | - Xin-Chuan Wang
- Shaanxi Traditional Chinese Medicine Hospital, Xi'an 710003, Shaanxi Province, China
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39
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Nagashima H, Sasaki N, Amano S, Nakamura S, Hayano M, Tsubota K. Oral administration of resveratrol or lactic acid bacterium improves lens elasticity. Sci Rep 2021; 11:2174. [PMID: 33500490 PMCID: PMC7838312 DOI: 10.1038/s41598-021-81748-w] [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: 09/30/2020] [Accepted: 01/08/2021] [Indexed: 02/03/2023] Open
Abstract
A decrease in the elasticity of the ocular lens during aging is associated with loss of the accommodative ability of the eye, leading to presbyopia. Although near vision impairment is a social issue affecting the length of healthy life expectancy and productivity of elderly people, an effective treatment to improve near vision has not yet become available. Here we examined the effect of Enterococcus faecium WB2000, Lactobacillus pentosus TJ515, and resveratrol on lens elasticity in rats, where the stiffness of the ocular lens increases exponentially during the aging process. A combination of WB2000 and resveratrol improved lens elasticity not only in the long term but also with just short-term treatment. In addition, TJ515 decreased stiffness in the eye lens with long-term treatment. Therefore, the oral administration of WB2000 and resveratrol or TJ515 may be a potential approach for managing the progression of near vision impairment.
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Affiliation(s)
- Hayato Nagashima
- Department of Ophthalmology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan
- Department of Plastic and Reconstructive Surgery, Keio University School of Medicine, Tokyo, Japan
| | - Nobunari Sasaki
- Department of Ophthalmology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan
- Tsubota Laboratory, Inc., Tokyo, Japan
| | - Sachie Amano
- Department of Ophthalmology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan
| | - Shigeru Nakamura
- Department of Ophthalmology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan
| | - Motoshi Hayano
- Department of Ophthalmology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan
- Tsubota Laboratory, Inc., Tokyo, Japan
| | - Kazuo Tsubota
- Department of Ophthalmology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan.
- Tsubota Laboratory, Inc., Tokyo, Japan.
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40
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Karnam S, Skiba NP, Rao PV. Biochemical and biomechanical characteristics of dystrophin-deficient mdx 3cv mouse lens. Biochim Biophys Acta Mol Basis Dis 2021; 1867:165998. [PMID: 33127476 PMCID: PMC8323981 DOI: 10.1016/j.bbadis.2020.165998] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Revised: 10/17/2020] [Accepted: 10/23/2020] [Indexed: 12/11/2022]
Abstract
The molecular and cellular basis for cataract development in mice lacking dystrophin, a scaffolding protein that links the cytoskeleton to the extracellular matrix, is poorly understood. In this study, we characterized lenses derived from the dystrophin-deficient mdx3cv mouse model. Expression of Dp71, a predominant isoform of dystrophin in the lens, was induced during lens fiber cell differentiation. Dp71 was found to co-distribute with dystroglycan, connexin-50 and 46, aquaporin-0, and NrCAM as a large cluster at the center of long arms of the hexagonal fibers. Although mdx3cv mouse lenses exhibited dramatically reduced levels of Dp71, only older lenses revealed punctate nuclear opacities compared to littermate wild type (WT) lenses. The levels of dystroglycan, syntrophin, and dystrobrevin which comprise the dystrophin-associated protein complex (DAPC), and NrCAM, connexin-50, and aquaporin-0, were significantly lower in the lens membrane fraction of adult mdx3cv mice compared to WT mice. Additionally, decreases were observed in myosin light chain phosphorylation and lens stiffness together with a significant elevation in the levels of utrophin, a functional homolog of dystrophin in mdx3cv mouse lenses compared to WT lenses. The levels of perlecan and laminin (ligands of α-dystroglycan) remained normal in dystrophin-deficient lens fibers. Taken together, although mdx3cv mouse lenses exhibit only minor defects in lens clarity possibly due to a compensatory increase in utrophin, the noted disruptions of DAPC, stability, and organization of membrane integral proteins of fibers, and stiffness of mdx3cv lenses reveal the importance of dystrophin and DAPC in maintaining lens clarity and function.
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Affiliation(s)
- Shruthi Karnam
- Department of Ophthalmology, Duke University School of Medicine, Durham, NC, USA
| | - Nikolai P Skiba
- Department of Ophthalmology, Duke University School of Medicine, Durham, NC, USA
| | - Ponugoti V Rao
- Department of Ophthalmology, Duke University School of Medicine, Durham, NC, USA; Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC, USA.
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41
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Hernebring M, Adelöf J, Wiseman J, Petersen A, Zetterberg M. H 2O 2-induced cataract as a model of age-related cataract: Lessons learned from overexpressing the proteasome activator PA28αβ in mouse eye lens. Exp Eye Res 2020; 203:108395. [PMID: 33310056 DOI: 10.1016/j.exer.2020.108395] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 11/18/2020] [Accepted: 12/07/2020] [Indexed: 02/06/2023]
Abstract
Cataract, the world-leading cause of blindness, is formed when crystallin aggregates cloud the eye lens. We overexpressed PA28αβ, a proteasome activator with properties protective against aggregation and oxidative stress, and examined whether they are less prone to develop cataract arisen from aging and/or hydrogen peroxide (H2O2) treatment. Another objective of this work was to compare the H2O2-induced cataracts of mouse lenses ex vivo to cataracts formed upon aging in mice. As part of an aging study of F2 hybrid C57BL/6NxBALB/c mice, ocular lenses of mature adult (7 months), middle-aged (15 months), and old (22 months of age) PA28αOE mice and their wildtype littermates (n = 22-44 lenses per group) were dissected and evaluated with regard to their cataractous state. In parallel, ocular lenses from 3 to 4 months old PA28αOE and wildtype C57BL/6 N littermates were treated with 100 μM H2O2 every 24 h for 7 days, with progression of cataract and physical appearance monitored daily. Lenses from both studies were also subjected to analysis of oxidative protein damage (carbonylation) and protein solubility. We found that overexpression of PA28αβ had no effect on neither age-related nor H2O2-induced cataract and conclude that overexpression of PA28αβ does not protect mice from developing cataract. The inefficiency of PA28αβ against cataract could be due to its anti-aggregation activity being already excessively present in the eye lens, exerted by crystallins. Crystallins are likely also constituting the 20-25 kDa proteins that were the dominant carbonyl targets in the eye lens irrespective of cataractous state. Assessment of H2O2-induced cataract in relation to age-related cataract demonstrated that high molecular weight protein carbonylation correlates to cataract both in vivo and ex vivo, while reduced protein solubility is more pronounced in age-related cataract. Furthermore, this work highlights vast dissimilarities in the physical manifestations of cataract upon aging and H2O2 ex vivo treatment. Age-related cataract initiation can take various forms, as a vague general blurriness or as a barely visible demarcated opacity, while H2O2-induced cataractogenesis seems to follow a specific scheme. In mice, this scheme begins with relatively opaque peripheral areas emerging that clear up later on as the lenses start to display a hat-like appearance. This transformation takes place synchronous to swelling of the eye lens, and is likely a result of osmotic disturbances causing a phase separation between the viscous lens cortex and the more solid fibers of the lens nucleus.
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Affiliation(s)
- Malin Hernebring
- Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Medicinaregatan 9A, PO Box 440, SE 405 30, Gothenburg, Sweden.
| | - Julia Adelöf
- Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Medicinaregatan 9A, PO Box 440, SE 405 30, Gothenburg, Sweden; Discovery Biology, Discovery Sciences, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Pepparedsleden 1, SE 431 53, Mölndal, Sweden
| | - John Wiseman
- Discovery Biology, Discovery Sciences, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Pepparedsleden 1, SE 431 53, Mölndal, Sweden
| | - Anne Petersen
- Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Medicinaregatan 9A, PO Box 440, SE 405 30, Gothenburg, Sweden
| | - Madeleine Zetterberg
- Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Medicinaregatan 9A, PO Box 440, SE 405 30, Gothenburg, Sweden; Department of Ophthalmology, Sahlgrenska University Hospital, Area 3, Göteborgsvägen 31, SE 431 80, Mölndal, Sweden
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42
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Gupta A, Ruminski D, Jimenez Villar A, Duarte Toledo R, Manzanera S, Panezai S, Mompean J, Artal P, Grulkowski I. In vivo SS-OCT imaging of crystalline lens sutures. BIOMEDICAL OPTICS EXPRESS 2020; 11:5388-5400. [PMID: 33149958 PMCID: PMC7587285 DOI: 10.1364/boe.401254] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Revised: 08/20/2020] [Accepted: 08/26/2020] [Indexed: 05/07/2023]
Abstract
We demonstrate in vivo three-dimensional (3-D) visualization of crystalline lens sutures in healthy eyes using swept source optical coherence tomography (SS-OCT). Volumetric data sets of the crystalline lenses were acquired and processed to obtain enhanced contrast projection images and to extract suture patterns in both anterior and posterior lens. The results presented different types of the sutures including Y-sutures, simple and complex star sutures. Age-related changes in suture arrangement were characterized quantitatively. Crystalline lens suture imaging with SS-OCT might be a useful tool in fundamental studies on development and ageing of human lens.
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Affiliation(s)
- Ashish Gupta
- Institute of Physics, Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University, ul. Grudziądzka 5, 87-100 Toruń, Poland
| | - Daniel Ruminski
- Institute of Physics, Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University, ul. Grudziądzka 5, 87-100 Toruń, Poland
| | - Alfonso Jimenez Villar
- Institute of Physics, Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University, ul. Grudziądzka 5, 87-100 Toruń, Poland
| | - Raúl Duarte Toledo
- Laboratorio de Óptica, Instituto Universitario de Investigación en Óptica y Nanofísica, Universidad de Murcia, Campus de Espinardo, E-30100, Murcia, Spain
| | - Silvestre Manzanera
- Laboratorio de Óptica, Instituto Universitario de Investigación en Óptica y Nanofísica, Universidad de Murcia, Campus de Espinardo, E-30100, Murcia, Spain
| | - Spozmai Panezai
- Institute of Physics, Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University, ul. Grudziądzka 5, 87-100 Toruń, Poland
| | - Juan Mompean
- Laboratorio de Óptica, Instituto Universitario de Investigación en Óptica y Nanofísica, Universidad de Murcia, Campus de Espinardo, E-30100, Murcia, Spain
| | - Pablo Artal
- Laboratorio de Óptica, Instituto Universitario de Investigación en Óptica y Nanofísica, Universidad de Murcia, Campus de Espinardo, E-30100, Murcia, Spain
| | - Ireneusz Grulkowski
- Institute of Physics, Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University, ul. Grudziądzka 5, 87-100 Toruń, Poland
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43
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Wang K, Hoshino M, Uesugi K, Yagi N, Young RD, Frost BE, Regini JW, Quantock AJ, Pierscionek BK. Cell compaction is not required for the development of gradient refractive index profiles in the embryonic chick lens. Exp Eye Res 2020; 197:108112. [DOI: 10.1016/j.exer.2020.108112] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 06/01/2020] [Accepted: 06/03/2020] [Indexed: 01/30/2023]
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44
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Muir ER, Pan X, Donaldson PJ, Vaghefi E, Jiang Z, Sellitto C, White TW. Multi-parametric MRI of the physiology and optics of the in-vivo mouse lens. Magn Reson Imaging 2020; 70:145-154. [PMID: 32380160 DOI: 10.1016/j.mri.2020.04.015] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Revised: 03/30/2020] [Accepted: 04/19/2020] [Indexed: 02/07/2023]
Abstract
The optics of the ocular lens are determined by its geometry (shape and volume) and its inherent gradient of refractive index (water to protein ratio), which are in turn maintained by unique cellular physiology known as the lens internal microcirculation system. Previously, magnetic resonance imaging (MRI) has been used on ex vivo organ cultured bovine lenses to show that pharmacological perturbations to this microcirculation system disrupt ionic and fluid homeostasis and overall lens optics. In this study, we have optimised in vivo MRI protocols for use on wild-type and transgenic mouse models so that the effects of genetically perturbing the lens microcirculation system on lens properties can be studied. In vivo MRI protocols and post-analysis methods for studying the mouse lens were optimised and used to measure the lens geometry, diffusion, T1 and T2, as well as the refractive index (n) calculated from T2, in wild-type mice and the genetically modified Cx50KI46 mouse. In this animal line, gap junctional coupling in the lens is increased by knocking in the gap junction protein Cx46 into the Cx50 locus. Relative to wild-type mice, Cx50KI46 mice showed significantly reduced lens size and radius of curvature, increased T1 and T2 values, and decreased n in the lens nucleus, which was consistent with the developmental and functional changes characterised previously in this lens model. These proof of principle experiments show that in vivo MRI can be applied to transgenic mouse models to gain mechanistic insights into the relationship between lens physiology and optics, and in the future suggest that longitudinal studies can be performed to determine how this relationship is altered by age in mouse models of cataract.
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Affiliation(s)
- Eric R Muir
- Department of Radiology, School of Medicine, Stony Brook University, Stony Brook, NY, USA
| | - Xingzheng Pan
- School of Optometry and Vision Science, New Zealand National Eye Centre, University of Auckland, New Zealand
| | - Paul J Donaldson
- School of Optometry and Vision Science, New Zealand National Eye Centre, University of Auckland, New Zealand; Department of Physiology, School of Medical Sciences, University of Auckland, New Zealand
| | - Ehsan Vaghefi
- School of Optometry and Vision Science, New Zealand National Eye Centre, University of Auckland, New Zealand
| | - Zhao Jiang
- Department of Radiology, School of Medicine, Stony Brook University, Stony Brook, NY, USA
| | - Caterina Sellitto
- Department of Physiology & Biophysics, School of Medicine, Stony Brook University, Stony Brook, NY, USA
| | - Thomas W White
- Department of Physiology & Biophysics, School of Medicine, Stony Brook University, Stony Brook, NY, USA.
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