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Linne C, Mon KY, D’Souza S, Jeong H, Jiang X, Brown DM, Zhang K, Vemaraju S, Tsubota K, Kurihara T, Pardue MT, Lang RA. Encephalopsin (OPN3) is required for normal refractive development and the GO/GROW response to induced myopia. Mol Vis 2023; 29:39-57. [PMID: 37287644 PMCID: PMC10243678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Accepted: 05/05/2023] [Indexed: 06/09/2023] Open
Abstract
Purpose Myopia, or nearsightedness, is the most common form of refractive error and is increasing in prevalence. While significant efforts have been made to identify genetic variants that predispose individuals to myopia, these variants are believed to account for only a small portion of the myopia prevalence, leading to a feedback theory of emmetropization, which depends on the active perception of environmental visual cues. Consequently, there has been renewed interest in studying myopia in the context of light perception, beginning with the opsin family of G-protein coupled receptors (GPCRs). Refractive phenotypes have been characterized in every opsin signaling pathway studied, leaving only Opsin 3 (OPN3), the most widely expressed and blue-light sensing noncanonical opsin, to be investigated for function in the eye and refraction. Methods Opn3 expression was assessed in various ocular tissues using an Opn3eGFP reporter. Weekly refractive development in Opn3 retinal and germline mutants from 3 to 9 weeks of age was measured using an infrared photorefractor and spectral domain optical coherence tomography (SD-OCT). Susceptibility to lens-induced myopia was then assessed using skull-mounted goggles with a -30 diopter experimental and a 0 diopter control lens. Mouse eye biometry was similarly tracked from 3 to 6 weeks. A myopia gene expression signature was assessed 24 h after lens induction for germline mutants to further assess myopia-induced changes. Results Opn3 was found to be expressed in a subset of retinal ganglion cells and a limited number of choroidal cells. Based on an assessment of Opn3 mutants, the OPN3 germline, but not retina conditional Opn3 knockout, exhibits a refractive myopia phenotype, which manifests in decreased lens thickness, shallower aqueous compartment depth, and shorter axial length, atypical of traditional axial myopias. Despite the short axial length, Opn3 null eyes demonstrate normal axial elongation in response to myopia induction and mild changes in choroidal thinning and myopic shift, suggesting that susceptibility to lens-induced myopia is largely unchanged. Additionally, the Opn3 null retinal gene expression signature in response to induced myopia after 24 h is distinct, with opposing Ctgf, Cx43, and Egr1 polarity compared to controls. Conclusions The data suggest that an OPN3 expression domain outside the retina can control lens shape and thus the refractive performance of the eye. Prior to this study, the role of Opn3 in the eye had not been investigated. This work adds OPN3 to the list of opsin family GPCRs that are implicated in emmetropization and myopia. Further, the work to exclude retinal OPN3 as the contributing domain in this refractive phenotype is unique and suggests a distinct mechanism when compared to other opsins.
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Affiliation(s)
- Courtney Linne
- Visual Systems Group, Abrahamson Pediatric Eye Institute, Division of Pediatric Ophthalmology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH
- Science of Light Center, Cincinnati Children's Hospital Medical Center, Cincinnati, OH
- Molecular & Developmental Biology Graduate Program, University of Cincinnati, College of Medicine, Cincinnati, OH
- Medical Scientist Training Program, University of Cincinnati, College of Medicine, Cincinnati, OH
| | - Khine Yin Mon
- Visual Systems Group, Abrahamson Pediatric Eye Institute, Division of Pediatric Ophthalmology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH
- Science of Light Center, Cincinnati Children's Hospital Medical Center, Cincinnati, OH
| | - Shane D’Souza
- Visual Systems Group, Abrahamson Pediatric Eye Institute, Division of Pediatric Ophthalmology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH
- Science of Light Center, Cincinnati Children's Hospital Medical Center, Cincinnati, OH
- Molecular & Developmental Biology Graduate Program, University of Cincinnati, College of Medicine, Cincinnati, OH
| | - Heonuk Jeong
- Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan
- Laboratory of Photobiology, Keio University School of Medicine, Tokyo, Japan
| | - Xiaoyan Jiang
- Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan
- Laboratory of Photobiology, Keio University School of Medicine, Tokyo, Japan
| | - Dillon M. Brown
- Department of Ophthalmology and Neuroscience Program, Emory University School of Medicine, Atlanta, GA
- Center for Visual and Neurocognitive Rehabilitation, Atlanta VA Health Care System, Decatur, GA
| | - Kevin Zhang
- Visual Systems Group, Abrahamson Pediatric Eye Institute, Division of Pediatric Ophthalmology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH
- Science of Light Center, Cincinnati Children's Hospital Medical Center, Cincinnati, OH
- Molecular & Developmental Biology Graduate Program, University of Cincinnati, College of Medicine, Cincinnati, OH
- Medical Scientist Training Program, University of Cincinnati, College of Medicine, Cincinnati, OH
| | - Shruti Vemaraju
- Visual Systems Group, Abrahamson Pediatric Eye Institute, Division of Pediatric Ophthalmology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH
- Science of Light Center, Cincinnati Children's Hospital Medical Center, Cincinnati, OH
- Department of Ophthalmology, College of Medicine, University of Cincinnati, Cincinnati, OH
| | - Kazuo Tsubota
- Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan
- Tsubota Laboratory, Inc., Tokyo, Japan
| | - Toshihide Kurihara
- Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan
- Laboratory of Photobiology, Keio University School of Medicine, Tokyo, Japan
| | - Machelle T. Pardue
- Department of Ophthalmology and Neuroscience Program, Emory University School of Medicine, Atlanta, GA
- Center for Visual and Neurocognitive Rehabilitation, Atlanta VA Health Care System, Decatur, GA
| | - Richard A. Lang
- Visual Systems Group, Abrahamson Pediatric Eye Institute, Division of Pediatric Ophthalmology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH
- Science of Light Center, Cincinnati Children's Hospital Medical Center, Cincinnati, OH
- Department of Ophthalmology, College of Medicine, University of Cincinnati, Cincinnati, OH
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Liu J, Lei Y, Diao Y, Lu Y, Teng X, Chen Q, Liu L, Zhong J. Altered whole-brain gray matter volume in form-deprivation myopia rats based on voxel-based morphometry: A pilot study. Front Neurosci 2023; 17:1113578. [PMID: 37144093 PMCID: PMC10151753 DOI: 10.3389/fnins.2023.1113578] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Accepted: 03/30/2023] [Indexed: 05/06/2023] Open
Abstract
Background Myopia is one of the major public health problems worldwide. However, the exact pathogenesis of myopia remains unclear. This study proposes using voxel-based morphometry (VBM) to investigate potential morphological alterations in gray matter volume (GMV) in form-deprivation myopia (FDM) rats. Methods A total of 14 rats with FDM (FDM group) and 15 normal controls (NC group) underwent high-resolution magnetic resonance imaging (MRI). Original T2 brain images were analyzed using VBM method to identify group differences in GMV. Following MRI examination, all rats were perfused with formalin, and immunohistochemical analysis of NeuN and c-fos levels was performed on the visual cortex. Results In the FDM group, compared to the NC group, significantly decreased GMVs were found in the left primary visual cortex, left secondary visual cortex, right subiculum, right cornu ammonis, right entorhinal cortex and bilateral molecular layer of the cerebellum. Additionally, significantly increased GMVs were found in the right dentate gyrus, parasubiculum, and olfactory bulb. Conclusions Our study revealed a positive correlation between mGMV and the expression of c-fos and NeuN in the visual cortex, suggesting a molecular relationship between cortical activity and macroscopic measurement of visual cortex structural plasticity. These findings may help elucidate the potential neural pathogenesis of FDM and its relationship to changes in specific brain regions.
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Affiliation(s)
- Jiayan Liu
- Department of Ophthalmology, First Affiliated Hospital of Jinan University, Jinan University, Guangzhou, China
- Department of Ophthalmology, The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan People’s Hospital, Qingyuan, China
| | - Yahui Lei
- Department of Ophthalmology, First Affiliated Hospital of Jinan University, Jinan University, Guangzhou, China
| | - Yuyao Diao
- Department of Ophthalmology, First Affiliated Hospital of Jinan University, Jinan University, Guangzhou, China
| | - Yamei Lu
- Department of Ophthalmology, The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan People’s Hospital, Qingyuan, China
| | - Xingbo Teng
- Department of Ophthalmology, First Affiliated Hospital of Jinan University, Jinan University, Guangzhou, China
| | - Qingting Chen
- Medical Imaging Center, First Affiliated Hospital of Jinan University, Guangzhou, China
| | - Lian Liu
- Department of Ophthalmology, First Affiliated Hospital of Jinan University, Jinan University, Guangzhou, China
| | - Jingxiang Zhong
- Department of Ophthalmology, First Affiliated Hospital of Jinan University, Jinan University, Guangzhou, China
- The Sixth Affiliated Hospital of Jinan University, Jinan University, Dongguan, China
- *Correspondence: Jingxiang Zhong,
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Ku H, Chen JJY, Hu M, Tien PT, Lin HJ, Xu G, Wan L, Gan D. Myopia Development in Tree Shrew Is Associated with Chronic Inflammatory Reactions. Curr Issues Mol Biol 2022; 44:4303-4313. [PMID: 36135208 PMCID: PMC9498061 DOI: 10.3390/cimb44090296] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Revised: 09/03/2022] [Accepted: 09/14/2022] [Indexed: 11/16/2022] Open
Abstract
In this study, we aimed to investigate whether chronic retinal inflammation is involved in the pathogenesis of form-deprivation myopia (FDM) using tree shrews as an animal model. Twenty-one tree shrews were randomly divided into 7-day/14-day FDM (FDM7/FDM14) groups and their corresponding 7-day/14-day control groups. Refraction and axial length were measured. To determine the effects of form deprivation on inflammation, we used real-time polymerase chain reaction (PCR) and immunohistochemistry to assess the expression levels of several proinflammatory cytokines. At day 0, the eyes in the FDM and control groups were hyperopic. However, after 7 and 14 days of form deprivation, the refractive error of the eyes in the FDM7 and FDM14 groups shifted from +6.6 ± 0.3 diopters (D) to +4.0 ± 0.5 D and from +6.4 ± 0.3 D to +5.0 ± 0.3 D, respectively. The levels of tumor necrosis factor-α, interleukin (IL)-6, IL-8, monocyte chemoattractant protein-1, and nuclear factor κB were increased in the FDM eyes, compared with those in the control eyes. The increase in matrix metalloproteinase-2 expression was greater in the FDM eyes than in the contralateral and control eyes, whereas collagen type I expression was downregulated. In conclusion, chronic inflammation may play a crucial pathogenic role in form-deprivation myopia in tree shrews.
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Affiliation(s)
- Hsiangyu Ku
- Department of Ophthalmology and Visual Science, Eye and ENT Hospital, Shanghai Medical College, Fudan University, Shanghai 200031, China
| | | | - Min Hu
- Department of Pediatric Ophthalmology, Hospital of Yunnan University, Kunming 650091, China
| | - Peng-Tai Tien
- Eye Center, China Medical University Hospital, Taichung 404333, Taiwan
- Graduate Institute of Clinical Medical Science, College of Medicine, China Medical University, Taichung 404333, Taiwan
| | - Hui-Ju Lin
- Eye Center, China Medical University Hospital, Taichung 404333, Taiwan
- School of Chinese Medicine, China Medical University, Taichung 404333, Taiwan
| | - Gezhi Xu
- Department of Ophthalmology and Visual Science, Eye and ENT Hospital, Shanghai Medical College, Fudan University, Shanghai 200031, China
- Shanghai Key Laboratory of Visual Impairment and Restoration, Shanghai 200031, China
- Key Laboratory of Myopia of State Health Ministry, Shanghai 200031, China
| | - Lei Wan
- School of Chinese Medicine, China Medical University, Taichung 404333, Taiwan
- Department of Biotechnology, Asia University, Taichung 404333, Taiwan
- Department of Obstetrics and Gynecology, China Medical University Hospital, Taichung 404333, Taiwan
- Correspondence: (L.W.); (D.G.)
| | - Dekang Gan
- Department of Ophthalmology and Visual Science, Eye and ENT Hospital, Shanghai Medical College, Fudan University, Shanghai 200031, China
- Correspondence: (L.W.); (D.G.)
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Gawne TJ, She Z, Norton TT. Chromatically simulated myopic blur counteracts a myopiagenic environment. Exp Eye Res 2022; 222:109187. [PMID: 35843288 DOI: 10.1016/j.exer.2022.109187] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Revised: 06/03/2022] [Accepted: 07/05/2022] [Indexed: 02/09/2023]
Abstract
There is a world-wide epidemic of myopia (nearsightedness), produced largely by human-made environmental visual cues that disrupt the emmetropization feedback mechanism that normally uses defocus cues to produce and maintain eyes in good focus. Previous studies have shown that the wavelength of light affects this process and that myopic defocus can slow the progression of myopia in children. We first asked if continuous exposure to a small cage with restricted viewing distance would produce an environmentally-induced myopia in tree shrews, small diurnal mammals closely related to primates. A group (n = 7) spent 11 days in a small cage with restricted viewing distance; one wall was a video display covered with Maltese crosses that included low-to-high spatial frequencies in the range visible to tree shrews. This group developed myopia (-1.2 ± 0.4 [stderr] D) that was significant relative to a colony group of seven animals (+1.0 ± 0.2 D) raised in mesh cages allowing more distant viewing. We then asked if chromatically-simulated myopic defocus, produced by blurring just the blue channel of the video display, would counteract this environmentally-induced myopia in a group of eight tree shrews. This group instead became significantly hyperopic (+4.0 ± 0.4 D) due to slowed axial elongation. These results demonstrate the high potency of chromatic cues in refractive regulation and may provide the basis for an anti-myopia treatment in humans.
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Affiliation(s)
- Timothy J Gawne
- Department of Optometry and Vision Science, University of Alabama at Birmingham (UAB), USA.
| | - Zhihui She
- Department of Optometry and Vision Science, University of Alabama at Birmingham (UAB), USA
| | - Thomas T Norton
- Department of Optometry and Vision Science, University of Alabama at Birmingham (UAB), USA
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5
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Goto S, Muroy SE, Zhang Y, Saijo K, Kolora SRR, Zhu Q, Wildsoet CF. Gene Expression Signatures of Contact Lens-Induced Myopia in Guinea Pig Retinal Pigment Epithelium. Invest Ophthalmol Vis Sci 2022; 63:25. [PMID: 36006019 PMCID: PMC9424971 DOI: 10.1167/iovs.63.9.25] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022] Open
Abstract
Purpose To identify key retinal pigment epithelium (RPE) genes linked to the induction of myopia in guinea pigs. Methods To induce myopia, two-week-old pigmented guinea pigs (New Zealand strain, n = 5) wore −10 diopter (D) rigid gas-permeable contact lenses (CLs), for one day; fellow eyes were left without CLs and served as controls. Spherical equivalent refractive errors (SE) and axial length (AL) were measured at baseline and one day after initiation of CL wear. RNA sequencing was applied to RPE collected from both treated and fellow (control) eyes after one day of CL-wear to identify related gene expression changes. Additional RPE-RNA samples from treated and fellow eyes were subjected to quantitative real-time PCR (qRT-PCR) analysis for validation purposes. Results The CLs induced myopia. The change from baseline values in SE was significantly different (P = 0.016), whereas there was no significant difference in the change in AL (P = 0.10). RNA sequencing revealed significant interocular differences in the expression in RPE of 13 genes: eight genes were significantly upregulated in treated eyes relative to their fellows, and five genes, including bone morphogenetic protein 2 (Bmp2), were significantly downregulated. The latter result was also confirmed by qRT-PCR. Additional analysis of differentially expressed genes revealed significant enrichment for bone morphogenetic protein (BMP) and TGF-β signaling pathways. Conclusions The results of this RPE gene expression study provide further supporting evidence for an important role of BMP2 in eye growth regulation, here from a guinea pig myopia model.
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Affiliation(s)
- So Goto
- Herbert Wertheim School Optometry and Vision Science, University of California, Berkeley, California, United States.,Department of Ophthalmology, Osaka University Graduate School of Medicine, Suita, Osaka, Japan.,Department of Ophthalmology, National Hospital Organization, Tokyo Medical Center, Meguro-ku, Tokyo, Japan
| | - Sandra E Muroy
- Department of Integrative Biology, Helen Wills Neuroscience Institute, University of California, Berkeley, California, United States
| | - Yan Zhang
- Herbert Wertheim School Optometry and Vision Science, University of California, Berkeley, California, United States
| | - Kaoru Saijo
- Department of Molecular & Cell Biology, Helen Wills Neuroscience Institute, University of California, Berkeley, California, United States
| | - Sree Rohit Raj Kolora
- Department of Integrative Biology, University of California, Berkeley, California, United States
| | - Qiurong Zhu
- Herbert Wertheim School Optometry and Vision Science, University of California, Berkeley, California, United States.,Department of Optometry and Visual Science, West China Hospital of Sichuan University, China
| | - Christine F Wildsoet
- Herbert Wertheim School Optometry and Vision Science, University of California, Berkeley, California, United States
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6
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Mai S, Zhu X, Wan EYC, Wu S, Yonathan JN, Wang J, Li Y, Ma JYW, Zuo B, Tse DYY, Lo PC, Wang X, Chan KM, Wu DM, Xiong W. Postnatal eye size in mice is controlled by SREBP2-mediated transcriptional repression of Lrp2 and Bmp2. Development 2022; 149:276005. [PMID: 35833708 PMCID: PMC9382895 DOI: 10.1242/dev.200633] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Accepted: 06/20/2022] [Indexed: 11/20/2022]
Abstract
Eye size is a key parameter of visual function, but the precise mechanisms of eye size control remain poorly understood. Here, we discovered that the lipogenic transcription factor sterol regulatory element-binding protein 2 (SREBP2) has an unanticipated function in the retinal pigment epithelium (RPE) to promote eye size in postnatal mice. SREBP2 transcriptionally represses low density lipoprotein receptor-related protein 2 (Lrp2), which has been shown to restrict eye overgrowth. Bone morphogenetic protein 2 (BMP2) is the downstream effector of Srebp2 and Lrp2, and Bmp2 is suppressed by SREBP2 transcriptionally but activated by Lrp2. During postnatal development, SREBP2 protein expression in the RPE decreases whereas that of Lrp2 and Bmp2 increases as the eye growth rate reduces. Bmp2 is the key determinant of eye size such that its level in mouse RPE inversely correlates with eye size. Notably, RPE-specific Bmp2 overexpression by adeno-associated virus effectively prevents the phenotypes caused by Lrp2 knock out. Together, our study shows that rapid postnatal eye size increase is governed by an RPE-derived signaling pathway, which consists of both positive and negative regulators of eye growth.
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Affiliation(s)
- Shuyi Mai
- Department of Biomedical Sciences, City University of Hong Kong, Hong Kong, China.,Key Laboratory of Biochip Technology, Biotech and Health Centre, Shenzhen Research Institute of City University of Hong Kong, Shenzhen, China.,Centre for Regenerative Medicine and Health, Hong Kong Institute of Science & Innovation, Chinese Academy of Sciences, Hong Kong, China
| | - Xiaoxuan Zhu
- Department of Biomedical Sciences, City University of Hong Kong, Hong Kong, China
| | - Esther Yi Ching Wan
- Department of Biomedical Sciences, City University of Hong Kong, Hong Kong, China
| | - Shengyu Wu
- Department of Biomedical Sciences, City University of Hong Kong, Hong Kong, China
| | | | - Jun Wang
- Department of Biomedical Sciences, City University of Hong Kong, Hong Kong, China
| | - Ying Li
- College of Information and Computer, Taiyuan University of Technology, 030024 Taiyuan, China
| | - Jessica Yuen Wuen Ma
- Centre for Myopia Research, School of Optometry, Hong Kong Polytechnic University, Hong Kong, China
| | - Bing Zuo
- Centre for Myopia Research, School of Optometry, Hong Kong Polytechnic University, Hong Kong, China
| | - Dennis Yan-Yin Tse
- Centre for Myopia Research, School of Optometry, Hong Kong Polytechnic University, Hong Kong, China.,Research Centre for SHARP Vision, Hong Kong Polytechnic University, Hong Kong, China
| | - Pui-Chi Lo
- Department of Biomedical Sciences, City University of Hong Kong, Hong Kong, China.,Key Laboratory of Biochip Technology, Biotech and Health Centre, Shenzhen Research Institute of City University of Hong Kong, Shenzhen, China
| | - Xin Wang
- Department of Surgery, The Chinese University of Hong Kong, Shatin, Hong Kong, China
| | - Kui Ming Chan
- Department of Biomedical Sciences, City University of Hong Kong, Hong Kong, China.,Key Laboratory of Biochip Technology, Biotech and Health Centre, Shenzhen Research Institute of City University of Hong Kong, Shenzhen, China
| | - David M Wu
- Massachusetts Eye and Ear Infirmary, Boston, MA 02114, USA
| | - Wenjun Xiong
- Department of Biomedical Sciences, City University of Hong Kong, Hong Kong, China.,Key Laboratory of Biochip Technology, Biotech and Health Centre, Shenzhen Research Institute of City University of Hong Kong, Shenzhen, China
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7
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Chen CW, Yao JY. RNA sequence analysis identified bone morphogenetic protein-2 (BMP2) as a biomarker underlying form deprivation myopia. Biochem Biophys Rep 2022; 30:101261. [PMID: 35494490 PMCID: PMC9043376 DOI: 10.1016/j.bbrep.2022.101261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Revised: 04/10/2022] [Accepted: 04/11/2022] [Indexed: 11/16/2022] Open
Abstract
Purpose Form deprivation myopia (FDM) is an urgent public issue characterized by pathological changes, but the underlying mechanism remained unclear. The aim was to investigate bone morphogenetic proteins (BMPs) utilizing the pathogenesis of FDM. Material and methods Gene expression omnibus (GEO) database was used to analyze one mRNA profile (GSE89325) of FDM. Sixteen retina samples (8 FDM and 8 controls) were randomly divided into seven groups for differential gene expression analysis in R. software. The gene pathway and protein-protein interaction (PPI) analysis were performed by the DAVID and STRING databases. Cytoscape was used to draw the PPI network. The gene ontology (GO) enrichment and Kyoto encyclopedia of genes and Genomes (KEGG) analysis were determined to achieve gene annotation and visualization. Results A total of 18420 differentially expressed genes (DEGs) were identified associated with FDM. The only non-significant gene (BEND6) was separately analyzed between two groups. Thirteen hub genes were discovered, ACVR1, ACVR2A, ACVR2B, RGMB, BMPR2, BMPR1A, BMP2, BMPR1B, CHRD, PTH, PTH1R, PTHLH, and WNT9A. The expression alteration in FDM were mainly enriched in cytokine-cytokine, and neuroactive ligand receptor interaction pathways. BMP2 was the key gene in myopia progression. Conclusions Of clinical perspective, our findings reveal that expression of BMP2 as an underlying mechanism of FDM, providing an insight for therapeutic interventions. BMP2 is a novel biomarker of myopia. Neuroactive ligand receptor interaction has some potential clinical applications. Estimating gene changes could become one of methods for myopia prevention.
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Liu AL, Liu YF, Wang G, Shao YQ, Yu CX, Yang Z, Zhou ZR, Han X, Gong X, Qian KW, Wang LQ, Ma YY, Zhong YM, Weng SJ, Yang XL. The role of ipRGCs in ocular growth and myopia development. SCIENCE ADVANCES 2022; 8:eabm9027. [PMID: 35675393 PMCID: PMC9176740 DOI: 10.1126/sciadv.abm9027] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
The increasing global prevalence of myopia calls for elaboration of the pathogenesis of this disease. Here, we show that selective ablation and activation of intrinsically photosensitive retinal ganglion cells (ipRGCs) in developing mice induced myopic and hyperopic refractive shifts by modulating the corneal radius of curvature (CRC) and axial length (AL) in an opposite way. Melanopsin- and rod/cone-driven signals of ipRGCs were found to influence refractive development by affecting the AL and CRC, respectively. The role of ipRGCs in myopia progression is evidenced by attenuated form-deprivation myopia magnitudes in ipRGC-ablated and melanopsin-deficient animals and by enhanced melanopsin expression/photoresponses in form-deprived eyes. Cell subtype-specific ablation showed that M1 subtype cells, and probably M2/M3 subtype cells, are involved in ocular development. Thus, ipRGCs contribute substantially to mouse eye growth and myopia development, which may inspire novel strategies for myopia intervention.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | - Shi-Jun Weng
- Corresponding author. (X.-L.Y.); (S.-J.W.); (Y.-M.Z.)
| | - Xiong-Li Yang
- Corresponding author. (X.-L.Y.); (S.-J.W.); (Y.-M.Z.)
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9
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Brown DM, Mazade R, Clarkson-Townsend D, Hogan K, Datta Roy PM, Pardue MT. Candidate pathways for retina to scleral signaling in refractive eye growth. Exp Eye Res 2022; 219:109071. [PMID: 35447101 PMCID: PMC9701099 DOI: 10.1016/j.exer.2022.109071] [Citation(s) in RCA: 34] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2022] [Revised: 03/25/2022] [Accepted: 04/05/2022] [Indexed: 12/22/2022]
Abstract
The global prevalence of myopia, or nearsightedness, has increased at an alarming rate over the last few decades. An eye is myopic if incoming light focuses prior to reaching the retinal photoreceptors, which indicates a mismatch in its shape and optical power. This mismatch commonly results from excessive axial elongation. Important drivers of the myopia epidemic include environmental factors, genetic factors, and their interactions, e.g., genetic factors influencing the effects of environmental factors. One factor often hypothesized to be a driver of the myopia epidemic is environmental light, which has changed drastically and rapidly on a global scale. In support of this, it is well established that eye size is regulated by a homeostatic process that incorporates visual cues (emmetropization). This process allows the eye to detect and minimize refractive errors quite accurately and locally over time by modulating the rate of elongation of the eye via remodeling its outermost coat, the sclera. Critically, emmetropization is not dependent on post-retinal processing. Thus, visual cues appear to influence axial elongation through a retina-to-sclera, or retinoscleral, signaling cascade, capable of transmitting information from the innermost layer of the eye to the outermost layer. Despite significant global research interest, the specifics of retinoscleral signaling pathways remain elusive. While a few pharmacological treatments have proven to be effective in slowing axial elongation (most notably topical atropine), the mechanisms behind these treatments are still not fully understood. Additionally, several retinal neuromodulators, neurotransmitters, and other small molecules have been found to influence axial length and/or refractive error or be influenced by myopigenic cues, yet little progress has been made explaining how the signal that originates in the retina crosses the highly vascular choroid to affect the sclera. Here, we compile and synthesize the evidence surrounding three of the major candidate pathways receiving significant research attention - dopamine, retinoic acid, and adenosine. All three candidates have both correlational and causal evidence backing their involvement in axial elongation and have been implicated by multiple independent research groups across diverse species. Two hypothesized mechanisms are presented for how a retina-originating signal crosses the choroid - via 1) all-trans retinoic acid or 2) choroidal blood flow influencing scleral oxygenation. Evidence of crosstalk between the pathways is discussed in the context of these two mechanisms.
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Affiliation(s)
- Dillon M Brown
- Department of Biomedical Engineering, Georgia Institute of Technology/Emory University, 313 Ferst Drive, Atlanta, GA, 30332, USA; Center for Visual and Neurocognitive Rehabilitation, Atlanta Veterans Affairs Healthcare System, 1670 Clairmont Rd, Atlanta, GA, 30033, USA
| | - Reece Mazade
- Department of Biomedical Engineering, Georgia Institute of Technology/Emory University, 313 Ferst Drive, Atlanta, GA, 30332, USA; Center for Visual and Neurocognitive Rehabilitation, Atlanta Veterans Affairs Healthcare System, 1670 Clairmont Rd, Atlanta, GA, 30033, USA
| | - Danielle Clarkson-Townsend
- Center for Visual and Neurocognitive Rehabilitation, Atlanta Veterans Affairs Healthcare System, 1670 Clairmont Rd, Atlanta, GA, 30033, USA; Division of Sleep and Circadian Disorders, Brigham and Women's Hospital, Harvard Medical School, 221 Longwood Avenue, Boston, MA, 02115, USA; Division of Sleep Medicine, Harvard Medical School, Boston, MA, 02115, USA; Gangarosa Department of Environmental Health, Emory University, 1518 Clifton Rd, Atlanta, GA, 30322, USA
| | - Kelleigh Hogan
- Department of Biomedical Engineering, Georgia Institute of Technology/Emory University, 313 Ferst Drive, Atlanta, GA, 30332, USA; Center for Visual and Neurocognitive Rehabilitation, Atlanta Veterans Affairs Healthcare System, 1670 Clairmont Rd, Atlanta, GA, 30033, USA
| | - Pooja M Datta Roy
- Department of Biomedical Engineering, Georgia Institute of Technology/Emory University, 313 Ferst Drive, Atlanta, GA, 30332, USA; Center for Visual and Neurocognitive Rehabilitation, Atlanta Veterans Affairs Healthcare System, 1670 Clairmont Rd, Atlanta, GA, 30033, USA
| | - Machelle T Pardue
- Department of Biomedical Engineering, Georgia Institute of Technology/Emory University, 313 Ferst Drive, Atlanta, GA, 30332, USA; Center for Visual and Neurocognitive Rehabilitation, Atlanta Veterans Affairs Healthcare System, 1670 Clairmont Rd, Atlanta, GA, 30033, USA.
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10
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Shan SSW, Wang PF, Cheung JKW, Yu F, Zheng H, Luo S, Yip SP, To CH, LAM C. Transcriptional profiling of the chick retina identifies down-regulation of VIP and UTS2B genes during early lens-induced myopia. Mol Omics 2022; 18:449-459. [DOI: 10.1039/d1mo00407g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Gene expression of the chick retina was examined during the early development of lens-induced myopia (LIM) using whole transcriptome sequencing. Monocular treatment of the right eyes with −10 diopter (D)...
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11
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Thomson K, Game J, Karouta C, Morgan IG, Ashby R. Correlation between small-scale methylation changes and gene expression during the development of myopia. FASEB J 2021; 36:e22129. [PMID: 34958689 DOI: 10.1096/fj.202101487r] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Revised: 12/07/2021] [Accepted: 12/16/2021] [Indexed: 12/11/2022]
Abstract
Visually induced changes in the expression of early growth response-1 (EGR1), FBJ osteosarcoma oncogene (FOS), and NGFI-A binding protein-2 (NAB2) appear to form a part of a retinal network fundamental to ocular growth regulation, and thus, the development of myopia (short-sightedness). However, it is unclear how environmental (visual) cues are translated into these molecular changes. One possibility is through epigenetic modifications such as DNA methylation, a known regulator of such processes. By sequencing bisulfite-converted DNA amplicons, this study examined whether changes in DNA methylation occur within specific regulatory and promoter regions of EGR1, FOS, and NAB2 during the periods of increased and decreased ocular growth in chicks. Visually induced changes in ocular growth rates were associated with single-point, but not large-scale, shifts in methylation levels within the investigated regions. Analysis of methylation pattern variability (entropy) demonstrated that the observed methylation changes are occurring within small subpopulations of retinal cells. This concurs with previous observations that EGR1 and FOS are differentially regulated at the peptide level within specific retinal cell types. Together, the findings of this study support a potential role for DNA methylation in the translation of external visual cues into molecular changes critical for ocular growth regulation and myopia development.
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Affiliation(s)
- Kate Thomson
- Centre for Research in Therapeutic Solutions, Faculty of Science and Technology, University of Canberra, Canberra, ACT, Australia
| | - Jeremy Game
- Centre for Research in Therapeutic Solutions, Faculty of Science and Technology, University of Canberra, Canberra, ACT, Australia
| | - Cindy Karouta
- Centre for Research in Therapeutic Solutions, Faculty of Science and Technology, University of Canberra, Canberra, ACT, Australia
| | - Ian G Morgan
- Research School of Biology, Australian National University, Canberra, ACT, Australia
| | - Regan Ashby
- Centre for Research in Therapeutic Solutions, Faculty of Science and Technology, University of Canberra, Canberra, ACT, Australia.,Research School of Biology, Australian National University, Canberra, ACT, Australia
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12
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Karouta C, Kucharski R, Hardy K, Thomson K, Maleszka R, Morgan I, Ashby R. Transcriptome-based insights into gene networks controlling myopia prevention. FASEB J 2021; 35:e21846. [PMID: 34405458 DOI: 10.1096/fj.202100350rr] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 07/21/2021] [Accepted: 07/23/2021] [Indexed: 11/11/2022]
Abstract
Myopia (short-sightedness), usually caused by excessive elongation of the eye during development, has reached epidemic proportions worldwide. In animal systems including the chicken model, several treatments have been shown to inhibit ocular elongation and experimental myopia. Although diverse in their apparent mechanism of action, each one leads to a reduction in the rate of ocular growth. We hypothesize that a defined set of retinal molecular changes may underlie growth inhibition, irrespective of the treatment agent used. Accordingly, across five well-established but diverse methods of inhibiting myopia, significant overlap is seen in the retinal transcriptome profile (transcript levels and alternative splicing events) in chicks when analyzed by RNA-seq. Within the two major pathway networks enriched during growth inhibition, that of cell signaling and circadian entrainment, transcription factors form the largest functional grouping. Importantly, a large percentage of those genes forming the defined retinal response are downstream targets of the transcription factor EGR1 which itself shows a universal response to all five growth-inhibitory treatments. This supports EGR1's previously implicated role in ocular growth regulation. Finally, by contrasting our data with human linkage and GWAS studies on refractive error, we confirm the applicability of our study to the human condition. Together, these findings suggest that a universal set of transcriptome changes, which sit within a well-defined retinal network that cannot be bypassed, is fundamental to growth regulation, thus paving a way for designing novel targets for myopia therapies.
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Affiliation(s)
- Cindy Karouta
- Centre for Research in Therapeutic Solutions, Biomedical Sciences, Faculty of Science and Technology, University of Canberra, Canberra, ACT, Australia
| | - Robert Kucharski
- Centre for Research in Therapeutic Solutions, Biomedical Sciences, Faculty of Science and Technology, University of Canberra, Canberra, ACT, Australia.,Research School of Biology, Australian National University, Canberra, ACT, Australia
| | - Kristine Hardy
- Centre for Research in Therapeutic Solutions, Biomedical Sciences, Faculty of Science and Technology, University of Canberra, Canberra, ACT, Australia
| | - Kate Thomson
- Centre for Research in Therapeutic Solutions, Biomedical Sciences, Faculty of Science and Technology, University of Canberra, Canberra, ACT, Australia
| | - Ryszard Maleszka
- Research School of Biology, Australian National University, Canberra, ACT, Australia
| | - Ian Morgan
- Research School of Biology, Australian National University, Canberra, ACT, Australia
| | - Regan Ashby
- Centre for Research in Therapeutic Solutions, Biomedical Sciences, Faculty of Science and Technology, University of Canberra, Canberra, ACT, Australia.,Research School of Biology, Australian National University, Canberra, ACT, Australia
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13
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Summers JA, Schaeffel F, Marcos S, Wu H, Tkatchenko AV. Functional integration of eye tissues and refractive eye development: Mechanisms and pathways. Exp Eye Res 2021; 209:108693. [PMID: 34228967 DOI: 10.1016/j.exer.2021.108693] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Revised: 06/28/2021] [Accepted: 06/30/2021] [Indexed: 12/16/2022]
Abstract
Refractive eye development is a tightly coordinated developmental process. The general layout of the eye and its various components are established during embryonic development, which involves a complex cross-tissue signaling. The eye then undergoes a refinement process during the postnatal emmetropization process, which relies heavily on the integration of environmental and genetic factors and is controlled by an elaborate genetic network. This genetic network encodes a multilayered signaling cascade, which converts visual stimuli into molecular signals that guide the postnatal growth of the eye. The signaling cascade underlying refractive eye development spans across all ocular tissues and comprises multiple signaling pathways. Notably, tissue-tissue interaction plays a key role in both embryonic eye development and postnatal eye emmetropization. Recent advances in eye biometry, physiological optics and systems genetics of refractive error have significantly advanced our understanding of the biological processes involved in refractive eye development and provided a framework for the development of new treatment options for myopia. In this review, we summarize the recent data on the mechanisms and signaling pathways underlying refractive eye development and discuss new evidence suggesting a wide-spread signal integration across different tissues and ocular components involved in visually guided eye growth.
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Affiliation(s)
- Jody A Summers
- Department of Cell Biology, University of Oklahoma Health Science Center, Oklahoma City, OK, USA
| | - Frank Schaeffel
- Section of Neurobiology of the Eye, Ophthalmic Research Institute, University of Tuebingen, Tuebingen, Germany; Myopia Research Group, Institute of Molecular and Clinical Ophthalmology Basel (IOB), Basel, Switzerland
| | - Susana Marcos
- Instituto de Óptica "Daza de Valdés", Consejo Superior de Investigaciones Científicas (CSIC), Madrid, Spain
| | - Hao Wu
- Department of Ophthalmology, Columbia University, New York, USA
| | - Andrei V Tkatchenko
- Department of Ophthalmology, Columbia University, New York, USA; Department of Pathology and Cell Biology, Columbia University, New York, USA.
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14
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Wen Y, Jin L, Zhang D, Zhang L, Xie C, Guo D, Wang Y, Wang L, Zhu M, Tong J, Shen Y. Quantitative proteomic analysis of scleras in guinea pig exposed to wavelength defocus. J Proteomics 2021; 243:104248. [PMID: 33964483 DOI: 10.1016/j.jprot.2021.104248] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Revised: 04/21/2021] [Accepted: 04/22/2021] [Indexed: 12/14/2022]
Abstract
Myopia is the most common optical disorder in the world, and wavelength defocus induced ametropia and myopia have attracted great attention. The objective was to identify and quantify scleral proteins involved in the response to the wavelength defocus. Guinea pigs were randomly divided into 3 groups that received different lighting conditions for 8 weeks: white light, short wavelength light, and long wavelength light. Refraction and axial length were measured, Hematoxylin-Eosin staining and transmission electron microscope were adopted to observe the scleral structure, and scleral proteome was also detected to analyze protein abundance by employing TMT labeling method. After light stimulation, the long- and short -wavelength light induced myopic and hyperopic effect on the guinea pig's eye and induced distinct protein signature, respectively. 186 dyregulated proteins between the short- and long-wavelength group were identified, which were mainly located in extracellular region and involved in metabolic process. We also found that 5 proteins in the guinea pigs scleras in response to wavelength defocus were also human myopic candidate targets, suggesting functional overlap between dyregulated proteins in scleral upon exposure to wavelength defocus and genes causing myopia in humans. SIGNIFICANCE: Wavelength defocus induces refractive errors and leads to myopia or hyperopia. However, sclera proteomics respond to wavelength defocus is lacking, which is crucial to understanding how wavelength defocus influences refractive development and induces myopia. In this proteome analysis, we identified unique protein signatures response to wavelength defocus in sclera of guinea pigs, identified potential mechanisms contributing to myopia formation, and found that several human myopia-related genes may involve in response to wavelength defocus. The results of this study provide a foundation to understand the mechanisms of myopia and wavelength defocus induced ametropia.
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Affiliation(s)
- Yingying Wen
- Department of Ophthalmology, First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310003, China; Clinical Research Center, First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310003, China
| | - Le Jin
- Department of Ophthalmology, First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310003, China; Clinical Research Center, First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310003, China
| | - Dongyan Zhang
- Department of Ophthalmology, First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310003, China; Clinical Research Center, First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310003, China
| | - Liyue Zhang
- Department of Ophthalmology, First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310003, China; Clinical Research Center, First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310003, China
| | - Chen Xie
- Department of Ophthalmology, First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310003, China; Clinical Research Center, First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310003, China
| | - Dongyu Guo
- Department of Ophthalmology, First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310003, China; Clinical Research Center, First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310003, China
| | - Yang Wang
- Department of Ophthalmology, First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310003, China; Clinical Research Center, First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310003, China
| | - Liyin Wang
- Department of Ophthalmology, First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310003, China; Clinical Research Center, First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310003, China
| | - Miaomiao Zhu
- Department of Ophthalmology, First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310003, China; Clinical Research Center, First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310003, China
| | - Jianping Tong
- Department of Ophthalmology, First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310003, China; Clinical Research Center, First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310003, China.
| | - Ye Shen
- Department of Ophthalmology, First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310003, China; Clinical Research Center, First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310003, China.
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15
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Zhu Q, Yang G, Chen B, Liu F, Li X, Liu L. Altered Expression of GJD2 Messenger RNA and the Coded Protein Connexin 36 in Negative Lens-induced Myopia of Guinea Pigs. Optom Vis Sci 2020; 97:1080-1088. [PMID: 33278187 PMCID: PMC7742206 DOI: 10.1097/opx.0000000000001611] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Accepted: 07/30/2020] [Indexed: 02/05/2023] Open
Abstract
SIGNIFICANCE Decreased expression of the retinal GJD2 gene messenger RNA (mRNA) and connexin 36 (Cx36) protein in the guinea pig negative lens-induced myopia (LIM) model suggests their involvement in local retinal circuits regulating eye growth. PURPOSE Previous studies suggest that the GJD2 gene and Cx36 protein encoded by the GJD2 gene play important roles in retinal signaling pathways and eye development. The aim of this study was to investigate the changes in GJD2 mRNA and Cx36 protein expression in the guinea pig lens-induced myopia model. METHODS Four-week-old guinea pigs were randomly divided into two groups. Animals in the experimental group were fitted with monocular -10 D lenses; and animals in the control group, with monocular plano lenses. Biometric measurements, including the spherical equivalent refractive error and axial length, were monitored. Animals were killed after 0, 1, 2, and 3 weeks of treatment, and their retinas were isolated. Retinal GJD2 mRNA and Cx36 protein expression levels were assessed by quantitative real-time polymerase chain reaction and Western blot analysis, respectively. RESULTS Spherical equivalent refractive error values indicated that negative lens-treated eyes became significantly more myopic than plano lens-treated eyes (P = .001), consistent with their longer axial lengths compared with those of control eyes. Both GJD2 mRNA and Cx36 protein expression levels were decreased in the retinas of negative lens-treated eyes compared with levels in the retinas of plano lens-treated eyes, although there were differences in the timing; GJD2 mRNA, levels were significantly decreased after 1 and 2 weeks of treatment (P = .01 and P = .004, respectively), whereas Cx36 protein expression was significantly decreased after only 1 week (P = .01). CONCLUSIONS That both retinal GJD2 mRNA and Cx36 protein expression levels were decreased after induction of myopia with negative lenses points to retinal circuits involving Cx36 in myopia development in the guinea pig.
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Affiliation(s)
- Qiurong Zhu
- Department of Optometry and Visual Science, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Guoyuan Yang
- Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Bingjie Chen
- Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Fengyang Liu
- Department of Optometry, Guizhou Provincial People's Hospital, Guiyang, Guizhou, China
| | - Xia Li
- Department of Optometry and Visual Science, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Longqian Liu
- Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, Sichuan, China
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16
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Zhang J, Zhang M, Zhao H, Xu X. Identification of proliferative diabetic retinopathy-associated genes on the protein–protein interaction network by using heat diffusion algorithm. Biochim Biophys Acta Mol Basis Dis 2020; 1866:165794. [DOI: 10.1016/j.bbadis.2020.165794] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Revised: 03/25/2020] [Accepted: 04/04/2020] [Indexed: 12/11/2022]
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17
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Zhang Y, Azmoun S, Hang A, Zeng J, Eng E, Wildsoet CF. Retinal defocus and form-deprivation induced regional differential gene expression of bone morphogenetic proteins in chick retinal pigment epithelium. J Comp Neurol 2020; 528:2864-2873. [PMID: 32452548 DOI: 10.1002/cne.24957] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Revised: 05/11/2020] [Accepted: 05/13/2020] [Indexed: 12/12/2022]
Abstract
We previously reported bidirectional gene expression regulation of the Bone Morphogenetic Proteins (BMP2, 4, and 7) in chick retinal pigment epithelium (RPE) in response to imposed optical defocus and form-deprivation (FD). This study investigated whether there are local (regional) differences in these effects. 19-day old White-Leghorn chicks wore monocular +10 or - 10 D lenses, or diffusers (FD) for 2 or 48 hr, after which RPE samples were collected from both eyes, from a central circular zone (3 mm radius), and 3 mm wide annular mid-peripheral and peripheral zones in all cases. BMP2, 4, and 7 gene expression levels in RPE from treated and fellow control eyes were compared as well as differences across zones. With the +10 D lens, increased expression of both BMP2 and BMP4 genes was observed in central and mid-peripheral zones but not the peripheral zone after 2 and 48 hr. In contrast, with the -10 D lens BMP2 gene expression was significantly decreased in all three zones after 2 and 48 hr. Similar patterns of BMP2 gene expression were observed in all three zones after 48 hr of FD. Smaller changes were recorded for BMP4 and BMP7 gene expression for both myopia-inducing treatments. That optical defocus- and FD-induced changes in BMP gene expression in chick RPE show treatment-dependent local (regional) differences suggest important differences in the nature and contributions of local retinal and underlying RPE regions to eye growth regulation.
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Affiliation(s)
- Yan Zhang
- School of Optometry, University of California, Berkeley, California, USA
| | - Sara Azmoun
- School of Optometry, University of California, Berkeley, California, USA
| | - Abraham Hang
- School of Optometry, University of California, Berkeley, California, USA
| | - Jiexi Zeng
- Department of Ophthalmology, the Second Xiangya Hospital, Central South University, Changsha, China
| | - Emily Eng
- School of Optometry, University of California, Berkeley, California, USA
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18
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Stone RA, Wei W, Sarfare S, McGeehan B, Engelhart KC, Khurana TS, Maguire MG, Iuvone PM, Nickla DL. Visual Image Quality Impacts Circadian Rhythm-Related Gene Expression in Retina and in Choroid: A Potential Mechanism for Ametropias. Invest Ophthalmol Vis Sci 2020; 61:13. [PMID: 32396635 PMCID: PMC7405616 DOI: 10.1167/iovs.61.5.13] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Accepted: 03/21/2020] [Indexed: 12/11/2022] Open
Abstract
Purpose Stimulated by evidence implicating diurnal/circadian rhythms and light in refractive development, we studied the expression over 24 hours of selected clock and circadian rhythm-related genes in retina/retinal pigment epithelium (RPE) and choroid of experimental ametropias in chicks. Methods Newly hatched chicks, entrained to a 12-hour light/dark cycle for 12 to 14 days, either experienced nonrestricted vision OU (i.e., in both eyes) or received an image-blurring diffuser or a minus 10-diopter (D) or a plus 10-D defocusing lens over one eye. Starting 1 day later and at 4-hour intervals for 24 hours, the retina/RPE and choroid were separately dissected. Without pooling, total RNA was extracted, converted to cDNA, and assayed by quantitative PCR for the expression of the following genes: Opn4m, Clock, Npas2, Per3, Cry1, Arntl, and Mtnr1a. Results The expression of each gene in retina/RPE and in choroid of eyes with nonrestricted vision OU varied over 24 hours, with equal levels OU for most genes and times. Altered visual input influenced gene expression in complex patterns that varied by gene, visual input, time, and eye, affecting experimental eyes with altered vision and also contralateral eyes with nonrestricted vision. Discussion Altering visual input in ways known to induce ametropias alters the retinal/RPE and choroidal expression of circadian rhythm-related genes, further linking circadian biology with eye growth regulation. While further investigations are needed, studying circadian processes may help understand refractive mechanisms and the increasing myopia prevalence in contemporary societies where lighting patterns can desynchronize endogenous rhythms from the natural environmental light/dark cycle.
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Affiliation(s)
- Richard A. Stone
- Department of Ophthalmology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, United States
| | - Wenjie Wei
- Department of Ophthalmology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, United States
| | - Shanta Sarfare
- Department of Bioscience, New England College of Optometry, Boston, Massachusetts, United States
| | - Brendan McGeehan
- Department of Ophthalmology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, United States
| | - K. Cameron Engelhart
- Department of Bioscience, New England College of Optometry, Boston, Massachusetts, United States
| | - Tejvir S. Khurana
- Department of Physiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, United States
| | - Maureen G. Maguire
- Department of Ophthalmology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, United States
| | - P. Michael Iuvone
- Departments of Ophthalmology and Pharmacology, Emory University School of Medicine, Atlanta, Georgia, United States
| | - Debora L. Nickla
- Department of Bioscience, New England College of Optometry, Boston, Massachusetts, United States
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Tkatchenko TV, Tkatchenko AV. Pharmacogenomic Approach to Antimyopia Drug Development: Pathways Lead the Way. Trends Pharmacol Sci 2019; 40:833-852. [PMID: 31676152 DOI: 10.1016/j.tips.2019.09.009] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Revised: 09/04/2019] [Accepted: 09/16/2019] [Indexed: 12/29/2022]
Abstract
Myopia is the most common eye disorder in the world which is caused by a mismatch between the optical power of the eye and its excessively long axial length. Recent studies revealed that the regulation of the axial length of the eye occurs via a complex signaling cascade, which originates in the retina and propagates across all ocular tissues to the sclera. The complexity of this regulatory cascade has made it particularly difficult to develop effective antimyopia drugs. The current pharmacological treatment options for myopia are limited to atropine and 7-methylxanthine, which have either significant adverse effects or low efficacy. In this review, we focus on the recent advances in genome-wide studies of the signaling pathways underlying myopia development and discuss the potential of systems genetics and pharmacogenomic approaches for the development of antimyopia drugs.
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Affiliation(s)
| | - Andrei V Tkatchenko
- Department of Ophthalmology, Columbia University, New York, NY, USA; Department of Pathology and Cell Biology, Columbia University, New York, NY, USA.
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20
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Guo L, Frost MR, Siegwart JT, Norton TT. Gene expression signatures in tree shrew sclera during recovery from minus-lens wear and during plus-lens wear. Mol Vis 2019; 25:311-328. [PMID: 31341380 PMCID: PMC6610222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2018] [Accepted: 06/17/2019] [Indexed: 11/04/2022] Open
Abstract
Purpose In juvenile tree shrews that have developed minus lens-induced myopia, if lens treatment is discontinued, refractive recovery (REC) occurs. However, in age-matched juvenile animals, plus-lens wear (PLW) produces little refractive change, although the visual stimulus (myopia) is similar (an "IGNORE" response). Because the sclera controls axial elongation and refractive error, we examined gene expression in the sclera produced by PLW and compared it with the gene expression signature produced by REC to learn whether these similar refractive conditions produce similar, or differing, scleral responses. Methods Eight groups of tree shrews (n = 7 per group) were examined. Four groups wore a monocular -5 D lens for 11 days until 35 days of visual experience (DVE). Lens wear was then discontinued, and the animals recovered for 0 h (REC-0), 2 h (REC-2h), 1 day (REC-1d), or 4 days (REC-4d). Starting at 35 DVE, three groups wore a monocular +5 D lens for 2 h (PLW-2h), 1 day (PLW-1d), or 4 days (PLW-4d). A normal group (PLW-0) was examined at 38 DVE to provide baseline measures. Using quantitative real-time PCR (qPCR), we examined scleral mRNA levels in recovering, plus-lens treated, and untreated control eyes for 55 candidate genes whose protein products included signaling molecules, metallopeptidases (MPs) and their inhibitors (tissue inhibitors of metallopeptidases [TIMPs]), and extracellular matrix proteins. Results No refractive recovery was measured in the REC-2h group. The scleral mRNA expression pattern for recovering versus untreated control eyes after 2 h of recovery was similar to that found for the group (REC-0) that had no recovery time. Many genes in both groups still had downregulated expression in the treated eyes versus the control eyes. The REC-1d group showed little refractive recovery (0.1 ± 0.1 D, mean ± standard error of the mean [SEM]), and the mRNA expression pattern was similar to that of the REC-2h group, but had fewer statistically significantly downregulated genes in the recovering eyes. The REC-4d group recovered refractively by 2.6 ± 0.4 D, and displayed a "STOP" gene expression signature of mostly upregulated mRNA expression in the recovering eyes compared with the untreated control eyes. The PLW-0 (normal) group and the PLW-2h group showed no statistically significant differential gene expression. The PLW-1d group showed a small hyperopic shift (0.1 ± 0.2 D). Two genes were differentially expressed: NPR3 was upregulated in the plus lens-wearing eyes, and IGF1 was downregulated. The PLW-4d group showed a similar hyperopic shift (0.3 ± 0.4 D), confirming that the plus lens-induced 5 D of myopia produced little refractive change. In the sclera, there was an IGNORE pattern of general differential upregulation of genes in the treated eyes (22 upregulated, one downregulated) that was distinct from the STOP signature found in recovery. Ten genes were upregulated in the REC-4d group and the PLW-4d group. However, ten other genes were differentially expressed in recovery, but not in plus-lens wear, while 12 genes were differentially expressed in plus-lens wear but not in recovery. Conclusions One day of recovery is not long enough for the emmetropization mechanism to produce significant gene expression changes in the sclera or refractive recovery. After 4 days, recovery and plus-lens wear produced altered scleral gene expression, but the patterns ("signatures") differed as to which genes showed altered expression, and whether the gene expression was up- or downregulated. Thus, myopia produced altered scleral mRNA expression in recovery and plus-lens wear, confirming that signals initiated by the retina reached the sclera, but the sclera in the elongated recovering eye responded differently from a normal sclera. This might have occurred because the recovering-eye sclera had remodeled during minus-lens compensation, making the sclera respond differently to the signals initiated by the retina. However, the myopia-produced retinal signals in plus lens-wearing animals also may have differed from those in the recovering eyes by the time the signals passed through the RPE and choroid to reach the sclera.
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21
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Altered ocular parameters from circadian clock gene disruptions. PLoS One 2019; 14:e0217111. [PMID: 31211778 PMCID: PMC6581257 DOI: 10.1371/journal.pone.0217111] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Accepted: 05/06/2019] [Indexed: 12/11/2022] Open
Abstract
The pathophysiology of refractive errors is poorly understood. Myopia (nearsightedness) in particular both blurs vision and predisposes the eye to many blinding diseases during adulthood. Based on past findings of diurnal variations in the dimensions of the eyes of humans and other vertebrates, altered diurnal rhythms of these ocular dimensions with experimentally induced myopia, and evolving evidence that ambient light exposures influence refractive development, we assessed whether disturbances in circadian signals might alter the refractive development of the eye. In mice, retinal-specific knockout of the clock gene Bmal1 induces myopia and elongates the vitreous chamber, the optical compartment separating the lens and the retina. These alterations simulate common ocular findings in clinical myopia. In Drosophila melanogaster, knockouts of the clock genes cycle or period lengthen the pseudocone, the optical component of the ommatidium that separates the facet lens from the photoreceptors. Disrupting circadian signaling thus alters optical development of the eye in widely separated species. We propose that mechanisms of myopia include circadian dysregulation, a frequent occurrence in modern societies where myopia also is both highly prevalent and increasing at alarming rates. Addressing circadian dysregulation may improve understanding of the pathogenesis of refractive errors and introduce novel therapeutic approaches to ameliorate myopia development in children.
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Troilo D, Smith EL, Nickla DL, Ashby R, Tkatchenko AV, Ostrin LA, Gawne TJ, Pardue MT, Summers JA, Kee CS, Schroedl F, Wahl S, Jones L. IMI - Report on Experimental Models of Emmetropization and Myopia. Invest Ophthalmol Vis Sci 2019; 60:M31-M88. [PMID: 30817827 PMCID: PMC6738517 DOI: 10.1167/iovs.18-25967] [Citation(s) in RCA: 215] [Impact Index Per Article: 43.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2018] [Accepted: 10/20/2018] [Indexed: 11/24/2022] Open
Abstract
The results of many studies in a variety of species have significantly advanced our understanding of the role of visual experience and the mechanisms of postnatal eye growth, and the development of myopia. This paper surveys and reviews the major contributions that experimental studies using animal models have made to our thinking about emmetropization and development of myopia. These studies established important concepts informing our knowledge of the visual regulation of eye growth and refractive development and have transformed treatment strategies for myopia. Several major findings have come from studies of experimental animal models. These include the eye's ability to detect the sign of retinal defocus and undergo compensatory growth, the local retinal control of eye growth, regulatory changes in choroidal thickness, and the identification of components in the biochemistry of eye growth leading to the characterization of signal cascades regulating eye growth and refractive state. Several of these findings provided the proofs of concepts that form the scientific basis of new and effective clinical treatments for controlling myopia progression in humans. Experimental animal models continue to provide new insights into the cellular and molecular mechanisms of eye growth control, including the identification of potential new targets for drug development and future treatments needed to stem the increasing prevalence of myopia and the vision-threatening conditions associated with this disease.
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Affiliation(s)
- David Troilo
- SUNY College of Optometry, State University of New York, New York, New York, United States
| | - Earl L. Smith
- College of Optometry, University of Houston, Houston, Texas, United States
| | - Debora L. Nickla
- Biomedical Sciences and Disease, New England College of Optometry, Boston, Massachusetts, United States
| | - Regan Ashby
- Health Research Institute, University of Canberra, Canberra, Australia
| | - Andrei V. Tkatchenko
- Department of Ophthalmology, Department of Pathology and Cell Biology, Columbia University, New York, New York, United States
| | - Lisa A. Ostrin
- College of Optometry, University of Houston, Houston, Texas, United States
| | - Timothy J. Gawne
- School of Optometry, University of Alabama Birmingham, Birmingham, Alabama, United States
| | - Machelle T. Pardue
- Biomedical Engineering, Georgia Tech College of Engineering, Atlanta, Georgia, United States31
| | - Jody A. Summers
- College of Medicine, University of Oklahoma, Oklahoma City, Oklahoma, United States
| | - Chea-su Kee
- School of Optometry, The Hong Kong Polytechnic University, Hong Kong, SAR, China
| | - Falk Schroedl
- Departments of Ophthalmology and Anatomy, Paracelsus Medical University, Salzburg, Austria
| | - Siegfried Wahl
- Institute for Ophthalmic Research, University of Tuebingen, Zeiss Vision Science Laboratory, Tuebingen, Germany
| | - Lyndon Jones
- CORE, School of Optometry and Vision Science, University of Waterloo, Ontario, Canada
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Giummarra L, Crewther SG, Riddell N, Murphy MJ, Crewther DP. Pathway analysis identifies altered mitochondrial metabolism, neurotransmission, structural pathways and complement cascade in retina/RPE/ choroid in chick model of form-deprivation myopia. PeerJ 2018; 6:e5048. [PMID: 29967729 PMCID: PMC6026464 DOI: 10.7717/peerj.5048] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Accepted: 05/31/2018] [Indexed: 12/15/2022] Open
Abstract
Purpose RNA sequencing analysis has demonstrated bidirectional changes in metabolism, structural and immune pathways during early induction of defocus induced myopia. Thus, the aim of this study was to investigate whether similar gene pathways are also related to the more excessive axial growth, ultrastructural and elemental microanalytic changes seen during the induction and recovery from form-deprivation myopia (FDM) in chicks and predicted by the RIDE model of myopia. Methods Archived genomic transcriptome data from the first three days of induction of monocularly occluded form deprived myopia (FDMI) in chicks was obtained from the GEO database (accession # GSE6543) while data from chicks monocularly occluded for 10 days and then given up to 24 h of normal visual recovery (FDMR) were collected. Gene set enrichment analysis (GSEA) software was used to determine enriched pathways during the induction (FDMI) and recovery (FDMR) from FD. Curated gene-sets were obtained from open access sources. Results Clusters of significant changes in mitochondrial energy metabolism, neurotransmission, ion channel transport, G protein coupled receptor signalling, complement cascades and neuron structure and growth were identified during the 10 days of induction of profound myopia and were found to correlate well with change in axial dimensions. Bile acid and bile salt metabolism pathways (cholesterol/lipid metabolism and sodium channel activation) were significantly upregulated during the first 24 h of recovery from 10 days of FDM. Conclusions The gene pathways altered during induction of FDM are similar to those reported in defocus induced myopia and are established indicators of oxidative stress, osmoregulatory and associated structural changes. These findings are also consistent with the choroidal thinning, axial elongation and hyperosmotic ion distribution patterns across the retina and choroid previously reported in FDM and predicted by RIDE.
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Affiliation(s)
- Loretta Giummarra
- School of Psychology & Public Health, La Trobe University, Melbourne, Victoria, Australia
| | - Sheila G Crewther
- School of Psychology & Public Health, La Trobe University, Melbourne, Victoria, Australia
| | - Nina Riddell
- School of Psychology & Public Health, La Trobe University, Melbourne, Victoria, Australia
| | - Melanie J Murphy
- School of Psychology & Public Health, La Trobe University, Melbourne, Victoria, Australia
| | - David P Crewther
- Centre for Psychopharmacology, Swinburne University of Technology, Hawthorn, Victoria, Australia
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Chakraborty R, Ostrin LA, Nickla DL, Iuvone PM, Pardue MT, Stone RA. Circadian rhythms, refractive development, and myopia. Ophthalmic Physiol Opt 2018; 38:217-245. [PMID: 29691928 PMCID: PMC6038122 DOI: 10.1111/opo.12453] [Citation(s) in RCA: 121] [Impact Index Per Article: 20.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Accepted: 03/11/2018] [Indexed: 12/14/2022]
Abstract
PURPOSE Despite extensive research, mechanisms regulating postnatal eye growth and those responsible for ametropias are poorly understood. With the marked recent increases in myopia prevalence, robust and biologically-based clinical therapies to normalize refractive development in childhood are needed. Here, we review classic and contemporary literature about how circadian biology might provide clues to develop a framework to improve the understanding of myopia etiology, and possibly lead to rational approaches to ameliorate refractive errors developing in children. RECENT FINDINGS Increasing evidence implicates diurnal and circadian rhythms in eye growth and refractive error development. In both humans and animals, ocular length and other anatomical and physiological features of the eye undergo diurnal oscillations. Systemically, such rhythms are primarily generated by the 'master clock' in the surpachiasmatic nucleus, which receives input from the intrinsically photosensitive retinal ganglion cells (ipRGCs) through the activation of the photopigment melanopsin. The retina also has an endogenous circadian clock. In laboratory animals developing experimental myopia, oscillations of ocular parameters are perturbed. Retinal signaling is now believed to influence refractive development; dopamine, an important neurotransmitter found in the retina, not only entrains intrinsic retinal rhythms to the light:dark cycle, but it also modulates refractive development. Circadian clocks comprise a transcription/translation feedback control mechanism utilizing so-called clock genes that have now been associated with experimental ametropias. Contemporary clinical research is also reviving ideas first proposed in the nineteenth century that light exposures might impact refraction in children. As a result, properties of ambient lighting are being investigated in refractive development. In other areas of medical science, circadian dysregulation is now thought to impact many non-ocular disorders, likely because the patterns of modern artificial lighting exert adverse physiological effects on circadian pacemakers. How, or if, such modern light exposures and circadian dysregulation contribute to refractive development is not known. SUMMARY The premise of this review is that circadian biology could be a productive area worthy of increased investigation, which might lead to the improved understanding of refractive development and improved therapeutic interventions.
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Affiliation(s)
- Ranjay Chakraborty
- College of Nursing and Health Sciences, Flinders University, Adelaide, Australia
| | | | | | | | - Machelle T. Pardue
- Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta
- Atlanta VA Center for Visual and Neurocognitive Rehabilitation, Decatur
| | - Richard A. Stone
- University of Pennsylvania School of Medicine, Philadelphia, USA
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Ward AH, Norton TT, Huisingh CE, Gawne TJ. The hyperopic effect of narrow-band long-wavelength light in tree shrews increases non-linearly with duration. Vision Res 2018; 146-147:9-17. [PMID: 29655781 DOI: 10.1016/j.visres.2018.03.006] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Revised: 02/28/2018] [Accepted: 03/05/2018] [Indexed: 10/17/2022]
Abstract
During postnatal refractive development, an emmetropization mechanism uses refractive error to modulate the growth rate of the eye. Hyperopia (image focused behind the retina) produces what has been described as "GO" signaling that increases growth. Myopia (image focused in front of the retina) produces "STOP" signaling that slows growth. The interaction between GO and STOP conditions is non-linear; brief daily exposure to STOP counteracts long periods of GO. In young tree shrews, long-wavelength (red) light, presented 14 h per day, also appears to produce STOP signals. We asked if red light also shows temporal non-linearity; does brief exposure slow the normal decrease in hyperopia in infant animals? At 11 days after eye opening (DVE), infant tree shrews (n = 5/group) began 13 days of daily treatment (red LEDs, 624 ± 10 or 636 ± 10 nm half peak intensity bandwidth) at durations of 0 h (normal animals, n = 7) or 1, 2, 4, or 7 h. Following each daily red period, colony lighting resumed. A 14 h red group had no colony lights. Refractive state was measured daily; ocular component dimensions at the end of the 13-day red-light period. Even 1 h of red light exposure produced some hyperopia. The average hyperopic shift from normal rose exponentially with duration (time constant 2.5 h). Vitreous chamber depth decreased non-linearly with duration (time constant, 3.3 h). After red treatment was discontinued, refractions in colony lighting recovered toward normal; the initial rate was linearly related to the amount of hyperopia. The red light may produce STOP signaling similar to myopic refractive error.
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Affiliation(s)
- Alexander H Ward
- Department of Optometry and Vision Science, University of Alabama at Birmingham, Birmingham, AL 35294, United States
| | - Thomas T Norton
- Department of Optometry and Vision Science, University of Alabama at Birmingham, Birmingham, AL 35294, United States
| | - Carrie E Huisingh
- Department of Ophthalmology, University of Alabama at Birmingham, Birmingham, AL 35294, United States
| | - Timothy J Gawne
- Department of Optometry and Vision Science, University of Alabama at Birmingham, Birmingham, AL 35294, United States.
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