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Yang M, Peng L, Lv L, Dai E, He Y, Zhao R, Li S. Characterization of a novel heterozygous frameshift variant in NDP gene that causes familial exudative vitreoretinopathy in female patients. Mol Genet Genomics 2024; 299:32. [PMID: 38472449 DOI: 10.1007/s00438-024-02128-3] [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: 03/14/2023] [Accepted: 10/28/2023] [Indexed: 03/14/2024]
Abstract
Familial exudative vitreoretinopathy (FEVR) is a severe inherited disease characterized by defective retinal vascular development. With genetic and clinical heterogeneity, FEVR can be inherited in different patterns and characterized by phenotypes ranging from moderate visual defects to complete vision loss. This study was conducted to unravel the genetic and functional etiology of a 4-month-old female FEVR patient. Targeted gene panel and Sanger sequencing were utilized for genetic evaluation. Luciferase assays, western blot, quantitive real-time PCR, and immunocytochemistry were performed to verify the functional defects in the identified candidate variant. Here, we report a 4-month-old girl with bilateral retinal folds and peripheral avascularization, and identified a novel frameshift heterozygous variant c.37dup (p.Leu13ProfsTer13) in NDP. In vitro experiments revealed that the Leu13ProfsTer13 variant led to a prominent decrease in protein levels instead of mRNA levels, resulting in compromised Norrin/β-catenin signaling activity. Human androgen receptor assay further revealed that a slight skewing of X chromosome inactivation could partially cause FEVR. Thus, the pathogenic mechanism by which heterozygous frameshift or nonsense variants in female carriers cause FEVR might largely result from a loss-of-function variant in one X chromosome allele and a slightly skewed X-inactivation. Further recruitment of more FEVR-affected females carrying NDP variants and genotype-phenotype correlation analysis can ultimately offer valuable information for the prognosis prediction of FEVR.
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Affiliation(s)
- Mu Yang
- Sichuan Provincial Key Laboratory for Human Disease Gene Study, Department of Laboratory Medicine, Center for Medical Genetics, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, 32 The First Ring Road West 2, Chengdu, 610072, Sichuan, China
- Research Unit of Blindness Prevention, Chinese Academy of Medical Sciences (No. 2019RU026), Sichuan Academy of Medical Sciences and Sichuan Provincial People's Hospital, Chengdu, China
| | - Li Peng
- Sichuan Provincial Key Laboratory for Human Disease Gene Study, Department of Laboratory Medicine, Center for Medical Genetics, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, 32 The First Ring Road West 2, Chengdu, 610072, Sichuan, China
- Research Unit of Blindness Prevention, Chinese Academy of Medical Sciences (No. 2019RU026), Sichuan Academy of Medical Sciences and Sichuan Provincial People's Hospital, Chengdu, China
| | - Liting Lv
- Sichuan Provincial Key Laboratory for Human Disease Gene Study, Department of Laboratory Medicine, Center for Medical Genetics, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, 32 The First Ring Road West 2, Chengdu, 610072, Sichuan, China
- Research Unit of Blindness Prevention, Chinese Academy of Medical Sciences (No. 2019RU026), Sichuan Academy of Medical Sciences and Sichuan Provincial People's Hospital, Chengdu, China
| | - Erkuan Dai
- Department of Ophthalmology, Xin Hua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yunqi He
- Sichuan Provincial Key Laboratory for Human Disease Gene Study, Department of Laboratory Medicine, Center for Medical Genetics, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, 32 The First Ring Road West 2, Chengdu, 610072, Sichuan, China
- Research Unit of Blindness Prevention, Chinese Academy of Medical Sciences (No. 2019RU026), Sichuan Academy of Medical Sciences and Sichuan Provincial People's Hospital, Chengdu, China
| | - Rulian Zhao
- Sichuan Provincial Key Laboratory for Human Disease Gene Study, Department of Laboratory Medicine, Center for Medical Genetics, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, 32 The First Ring Road West 2, Chengdu, 610072, Sichuan, China
- Research Unit of Blindness Prevention, Chinese Academy of Medical Sciences (No. 2019RU026), Sichuan Academy of Medical Sciences and Sichuan Provincial People's Hospital, Chengdu, China
| | - Shujin Li
- Sichuan Provincial Key Laboratory for Human Disease Gene Study, Department of Laboratory Medicine, Center for Medical Genetics, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, 32 The First Ring Road West 2, Chengdu, 610072, Sichuan, China.
- Research Unit of Blindness Prevention, Chinese Academy of Medical Sciences (No. 2019RU026), Sichuan Academy of Medical Sciences and Sichuan Provincial People's Hospital, Chengdu, China.
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Liu M, Dai E, Yang M, Li S, Fan L, Liu Y, Xiao H, Zhao P, Yang Z. Investigating the Impact of Dimer Interface Mutations on Norrin's Secretion and Norrin/β-Catenin Pathway Activation. Invest Ophthalmol Vis Sci 2024; 65:31. [PMID: 38517429 PMCID: PMC10981164 DOI: 10.1167/iovs.65.3.31] [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: 11/29/2023] [Accepted: 03/01/2024] [Indexed: 03/23/2024] Open
Abstract
Purpose This study aimed to investigate the impact of 21 NDP mutations located at the dimer interface, focusing on their potential effects on protein assembly, secretion efficiency, and activation of the Norrin/β-catenin signaling pathway. Methods The expression level, secretion efficiency, and protein assembly of mutations were analyzed using Western blot. The Norrin/β-catenin signaling pathway activation ability after overexpression of mutants or supernatant incubation of mutant proteins was tested in HEK293STF cells. The mutant norrin and wild-type (WT) FZD4 were overexpressed in HeLa cells to observe their co-localization. Immunofluorescence staining was conducted in HeLa cells to analyze the subcellular localization of Norrin and the Retention Using Selective Hook (RUSH) assay was used to dynamically observe the secretion process of WT and mutant Norrin. Results Four mutants (A63S, E66K, H68P, and L103Q) exhibited no significant differences from WT in all evaluations. The other 17 mutants presented abnormalities, including inadequate protein assembly, reduced secretion, inability to bind to FZD4 on the cell membrane, and decreased capacity to activate Norrin/β-catenin signaling pathway. The RUSH assay revealed the delay in endoplasmic reticulum (ER) exit and impairment of Golgi transport. Conclusions Mutations at the Norrin dimer interface may lead to abnormal protein assembly, inability to bind to FZD4, and decreased secretion, thus contributing to compromised Norrin/β-catenin signaling. Our results shed light on the pathogenic mechanisms behind a significant proportion of NDP gene mutations in familial exudative vitreoretinopathy (FEVR) or Norrie disease.
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Affiliation(s)
- Min Liu
- Sichuan Provincial Key Laboratory for Human Disease Gene Study, Center for Medical Genetics and Department of Laboratory Medicine, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, China
- Research Unit for Blindness Prevention, Chinese Academy of Medical Sciences (2019RU026), Sichuan Provincial People's Hospital, Chengdu, Sichuan, China
| | - Erkuan Dai
- Department of Ophthalmology, Xin Hua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Mu Yang
- Sichuan Provincial Key Laboratory for Human Disease Gene Study, Center for Medical Genetics and Department of Laboratory Medicine, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, China
- Research Unit for Blindness Prevention, Chinese Academy of Medical Sciences (2019RU026), Sichuan Provincial People's Hospital, Chengdu, Sichuan, China
| | - Shujin Li
- Sichuan Provincial Key Laboratory for Human Disease Gene Study, Center for Medical Genetics and Department of Laboratory Medicine, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, China
- Research Unit for Blindness Prevention, Chinese Academy of Medical Sciences (2019RU026), Sichuan Provincial People's Hospital, Chengdu, Sichuan, China
| | - Lin Fan
- The University of Chinese Academy of Sciences, Beijing, China
| | - Yining Liu
- Sichuan Provincial Key Laboratory for Human Disease Gene Study, Center for Medical Genetics and Department of Laboratory Medicine, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, China
- Research Unit for Blindness Prevention, Chinese Academy of Medical Sciences (2019RU026), Sichuan Provincial People's Hospital, Chengdu, Sichuan, China
| | - Haodong Xiao
- Department of Ophthalmology, Xin Hua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Peiquan Zhao
- Department of Ophthalmology, Xin Hua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Zhenglin Yang
- Sichuan Provincial Key Laboratory for Human Disease Gene Study, Center for Medical Genetics and Department of Laboratory Medicine, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, China
- Research Unit for Blindness Prevention, Chinese Academy of Medical Sciences (2019RU026), Sichuan Provincial People's Hospital, Chengdu, Sichuan, China
- The University of Chinese Academy of Sciences, Beijing, China
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Jiang K, Wang S, Sun H, Peng C, Li N, Li S, Gao R, Zhang J. Novel mutation in the NDP gene associated with Norrie disease in a Chinese pedigree. Mol Genet Genomic Med 2024; 12:e2345. [PMID: 38146894 PMCID: PMC10767683 DOI: 10.1002/mgg3.2345] [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: 07/06/2023] [Revised: 11/08/2023] [Accepted: 12/07/2023] [Indexed: 12/27/2023] Open
Abstract
PURPOSE Norrie disease (ND) is a rare X-linked recessive disorder characteristic of early childhood blindness. While several mutations in the NDP gene have been reported as causative for ND, the genetic etiology remains unknown for many patients. This study aims to describe a novel mutation and explore the clinical manifestations in a Chinese family with two affected males. METHODS Exome sequencing (ES) was employed to identify the causative gene in a four-generation pedigree. Sanger sequencing was subsequently utilized to validate the mutation detected by ES in additional family members. Ophthalmologic examination and diagnostic imaging relevant to ND were conducted. RESULTS The proband (IV:2), an 8-month-old male infant, presented with binocular retinal detachment. DNA sequencing revealed a novel heterozygous missense mutation (c.174G>C) within the NDP gene in the proband. This mutation affected highly conserved residues and was predicted to disrupt the normal protein structure. Furthermore, the variant co-segregated with the disease phenotypes within the family. CONCLUSIONS Our findings identified a novel missense mutation in the NDP gene associated with Norrie disease in China, expanding the mutation spectrum associated with ND. This discovery holds diagnostic, prognostic, and genetic counseling implications for affected individuals.
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Affiliation(s)
- Keke Jiang
- Department of Ophthalmology, Zhengda Guangming Ophthalmology GroupWeifang Eye HospitalWeifangChina
| | - Shuying Wang
- Department of OphthalmologyGaomi People's HospitalWeifangChina
| | - Huixin Sun
- Department of OphthalmologyWeifang Medical UniversityWeifangChina
| | - Chuanzhi Peng
- Department of OphthalmologyWeifang Medical UniversityWeifangChina
| | - Nan Li
- Department of Ophthalmology, Zhengda Guangming Ophthalmology GroupWeifang Eye HospitalWeifangChina
| | - Shuchan Li
- Department of Ophthalmology, Zhengda Guangming Ophthalmology GroupWeifang Eye HospitalWeifangChina
| | - Rongyu Gao
- Department of Ophthalmology, Zhengda Guangming Ophthalmology GroupWeifang Eye HospitalWeifangChina
| | - Jie Zhang
- Department of Ophthalmology, Zhengda Guangming Ophthalmology GroupWeifang Eye HospitalWeifangChina
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Zhang S, Yong HM, Zou G, Ma MJ, Rui X, Yang SY, Sheng XL. De novel heterozygous copy number deletion on 7q31.31-7q31.32 involving TSPAN12 gene with familial exudative vitreoretinopathy in a Chinese family. Int J Ophthalmol 2023; 16:1952-1961. [PMID: 38111929 PMCID: PMC10700080 DOI: 10.18240/ijo.2023.12.06] [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: 07/28/2023] [Accepted: 10/30/2023] [Indexed: 12/20/2023] Open
Abstract
AIM To investigate the genetic and clinical characteristics of patients with a large heterozygous copy number deletion on 7q31.31-7q31.32. METHODS A family with familial exudative vitreoretinopathy (FEVR) phenotype was included in the study. Whole-exome sequencing (WES) was initially used to locate copy number variations (CNVs) on 7q31.31-31.32, but failed to detect the precise breakpoint. The long-read sequencing, Oxford Nanopore sequencing Technology (ONT) was used to get the accurate breakpoint which is verified by quantitative real-time polymerase chain reaction (QPCR) and Sanger Sequencing. RESULTS The proband, along with her father and younger brother, were found to have a heterozygous 4.5 Mb CNV deletion located on 7q31.31-31.32, which included the FEVR-related gene TSPAN12. The specific deletion was confirmed as del(7)(q31.31q31.32)chr7:g.119451239_123956818del. The proband exhibited a phase 2A FEVR phenotype, characterized by a falciform retinal fold, macular dragging, and peripheral neovascularization with leaking of fluorescence. These symptoms led to a significant decrease in visual acuity in both eyes. On the other hand, the affected father and younger brother showed a milder phenotype. CONCLUSION The heterozygous CNV deletion located on 7q31.31-7q31.32 is associated with the FEVR phenotype. The use of long-read sequencing techniques is essential for accurate molecular diagnosis of genetic disorders.
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Affiliation(s)
- Shuang Zhang
- People's Hospital of Ningxia Hui Autonomous Region, Ningxia Medical University, Ningxia Eye Hospital, Ningxia Clinical Research Center on Diseases of Blindness in Eye, Yinchuan 750001, Ningxia Hui Autonomous Region, China
| | - Hai-Ming Yong
- People's Hospital of Ningxia Hui Autonomous Region, Ningxia Medical University, Ningxia Eye Hospital, Ningxia Clinical Research Center on Diseases of Blindness in Eye, Yinchuan 750001, Ningxia Hui Autonomous Region, China
| | - Gang Zou
- People's Hospital of Ningxia Hui Autonomous Region, Ningxia Medical University, Ningxia Eye Hospital, Ningxia Clinical Research Center on Diseases of Blindness in Eye, Yinchuan 750001, Ningxia Hui Autonomous Region, China
| | - Mei-Jiao Ma
- People's Hospital of Ningxia Hui Autonomous Region, Ningxia Medical University, Ningxia Eye Hospital, Ningxia Clinical Research Center on Diseases of Blindness in Eye, Yinchuan 750001, Ningxia Hui Autonomous Region, China
| | - Xue Rui
- People's Hospital of Ningxia Hui Autonomous Region, Ningxia Medical University, Ningxia Eye Hospital, Ningxia Clinical Research Center on Diseases of Blindness in Eye, Yinchuan 750001, Ningxia Hui Autonomous Region, China
| | - Shang-Ying Yang
- People's Hospital of Ningxia Hui Autonomous Region, Ningxia Medical University, Ningxia Eye Hospital, Ningxia Clinical Research Center on Diseases of Blindness in Eye, Yinchuan 750001, Ningxia Hui Autonomous Region, China
| | - Xun-Lun Sheng
- People's Hospital of Ningxia Hui Autonomous Region, Ningxia Medical University, Ningxia Eye Hospital, Ningxia Clinical Research Center on Diseases of Blindness in Eye, Yinchuan 750001, Ningxia Hui Autonomous Region, China
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Pauzuolyte V, Patel A, Wawrzynski JR, Ingham NJ, Leong YC, Karda R, Bitner‐Glindzicz M, Berger W, Waddington SN, Steel KP, Sowden JC. Systemic gene therapy rescues retinal dysfunction and hearing loss in a model of Norrie disease. EMBO Mol Med 2023; 15:e17393. [PMID: 37642150 PMCID: PMC10565640 DOI: 10.15252/emmm.202317393] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Revised: 07/24/2023] [Accepted: 07/25/2023] [Indexed: 08/31/2023] Open
Abstract
Deafness affects 5% of the world's population, yet there is a lack of treatments to prevent hearing loss due to genetic causes. Norrie disease is a recessive X-linked disorder, caused by NDP gene mutation. It manifests as blindness at birth and progressive sensorineural hearing loss, leading to debilitating dual sensory deprivation. To develop a gene therapy, we used a Norrie disease mouse model (Ndptm1Wbrg ), which recapitulates abnormal retinal vascularisation and progressive hearing loss. We delivered human NDP cDNA by intravenous injection of adeno-associated viral vector (AAV)9 at neonatal, juvenile and young adult pathological stages and investigated its therapeutic effects on the retina and cochlea. Neonatal treatment prevented the death of the sensory cochlear hair cells and rescued cochlear disease biomarkers as demonstrated by RNAseq and physiological measurements of auditory function. Retinal vascularisation and electroretinograms were restored to normal by neonatal treatment. Delivery of NDP gene therapy after the onset of the degenerative inner ear disease also ameliorated the cochlear pathology, supporting the feasibility of a clinical treatment for progressive hearing loss in people with Norrie disease.
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Affiliation(s)
- Valda Pauzuolyte
- UCL Great Ormond Street Institute of Child Health, University College LondonLondonUK
- NIHR Great Ormond Street Hospital Biomedical Research CentreLondonUK
| | - Aara Patel
- UCL Great Ormond Street Institute of Child Health, University College LondonLondonUK
- NIHR Great Ormond Street Hospital Biomedical Research CentreLondonUK
| | - James R Wawrzynski
- UCL Great Ormond Street Institute of Child Health, University College LondonLondonUK
- NIHR Great Ormond Street Hospital Biomedical Research CentreLondonUK
| | - Neil J Ingham
- Wolfson Centre for Age‐Related Diseases, King's College LondonLondonUK
| | - Yeh Chwan Leong
- UCL Great Ormond Street Institute of Child Health, University College LondonLondonUK
- NIHR Great Ormond Street Hospital Biomedical Research CentreLondonUK
| | - Rajvinder Karda
- EGA Institute for Woman's Health, University College LondonLondonUK
| | - Maria Bitner‐Glindzicz
- UCL Great Ormond Street Institute of Child Health, University College LondonLondonUK
- NIHR Great Ormond Street Hospital Biomedical Research CentreLondonUK
| | - Wolfgang Berger
- Institute of Medical Molecular Genetics, University of ZürichZürichSwitzerland
- Zurich Center for Integrative Human Physiology (ZIHP), University of ZürichZürichSwitzerland
- Neuroscience Center Zurich, University and ETH Zurich, University of ZürichZürichSwitzerland
| | - Simon N Waddington
- EGA Institute for Woman's Health, University College LondonLondonUK
- MRC Antiviral Gene Therapy Research Unit, Faculty of Health SciencesUniversity of the WitswatersrandJohannesburgSouth Africa
| | - Karen P Steel
- Wolfson Centre for Age‐Related Diseases, King's College LondonLondonUK
| | - Jane C Sowden
- UCL Great Ormond Street Institute of Child Health, University College LondonLondonUK
- NIHR Great Ormond Street Hospital Biomedical Research CentreLondonUK
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Xie EF, Hilkert Rodriguez S, Xie B, D’Souza M, Reem G, Sulakhe D, Skondra D. Identifying novel candidate compounds for therapeutic strategies in retinopathy of prematurity via computational drug-gene association analysis. Front Pediatr 2023; 11:1151239. [PMID: 37492605 PMCID: PMC10365641 DOI: 10.3389/fped.2023.1151239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Accepted: 06/26/2023] [Indexed: 07/27/2023] Open
Abstract
Purpose Retinopathy of prematurity (ROP) is the leading cause of preventable childhood blindness worldwide. Although interventions such as anti-VEGF and laser have high success rates in treating severe ROP, current treatment and preventative strategies still have their limitations. Thus, we aim to identify drugs and chemicals for ROP with comprehensive safety profiles and tolerability using a computational bioinformatics approach. Methods We generated a list of genes associated with ROP to date by querying PubMed Gene which draws from animal models, human studies, and genomic studies in the NCBI database. Gene enrichment analysis was performed on the ROP gene list with the ToppGene program which draws from multiple drug-gene interaction databases to predict compounds with significant associations to the ROP gene list. Compounds with significant toxicities or without known clinical indications were filtered out from the final drug list. Results The NCBI query identified 47 ROP genes with pharmacologic annotations present in ToppGene. Enrichment analysis revealed multiple drugs and chemical compounds related to the ROP gene list. The top ten most significant compounds associated with ROP include ascorbic acid, simvastatin, acetylcysteine, niacin, castor oil, penicillamine, curcumin, losartan, capsaicin, and metformin. Antioxidants, NSAIDs, antihypertensives, and anti-diabetics are the most common top drug classes derived from this analysis, and many of these compounds have potential to be readily repurposed for ROP as new prevention and treatment strategies. Conclusion This bioinformatics analysis creates an unbiased approach for drug discovery by identifying compounds associated to the known genes and pathways of ROP. While predictions from bioinformatic studies require preclinical/clinical studies to validate their results, this technique could certainly guide future investigations for pathologies like ROP.
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Affiliation(s)
- Edward F. Xie
- Chicago Medical School, Rosalind Franklin University of Medicine and Science, Chicago, IL, United States
| | - Sarah Hilkert Rodriguez
- Department of Ophthalmology and Visual Science, University of Chicago, Chicago, IL, United States
| | - Bingqing Xie
- Department of Medicine, University of Chicago, Chicago, IL, United States
| | - Mark D’Souza
- Center for Research Informatics, The University of Chicago, Chicago, IL, United States
| | - Gonnah Reem
- Department of Ophthalmology and Visual Science, University of Chicago, Chicago, IL, United States
| | - Dinanath Sulakhe
- Center for Research Informatics, The University of Chicago, Chicago, IL, United States
| | - Dimitra Skondra
- Department of Ophthalmology and Visual Science, University of Chicago, Chicago, IL, United States
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Selective Activation of the Wnt-Signaling Pathway as a Novel Therapy for the Treatment of Diabetic Retinopathy and Other Retinal Vascular Diseases. Pharmaceutics 2022; 14:pharmaceutics14112476. [PMID: 36432666 PMCID: PMC9697247 DOI: 10.3390/pharmaceutics14112476] [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: 09/28/2022] [Revised: 11/07/2022] [Accepted: 11/14/2022] [Indexed: 11/18/2022] Open
Abstract
Retinal ischemia, often associated with various disorders such as diabetic retinopathy (DR), retinal vein occlusion, glaucoma, optic neuropathies, stroke, and other retinopathies, is a major cause of visual impairment and blindness worldwide. As proper blood supply to the retina is critical to maintain its high metabolic demand, any impediment to blood flow can lead to a decrease in oxygen supply, resulting in retinal ischemia. In the pathogenesis of DR, including diabetic macular edema (DME), elevated blood glucose leads to blood-retina barrier (BRB) disruptions, vascular leakage, and capillary occlusion and dropouts, causing insufficient delivery of oxygen to the retina, and ultimately resulting in visual impairment. Other potential causes of DR include neuronal dysfunction in the absence of vascular defect, genetic, and environmental factors. The exact disease progression remains unclear and varies from patient to patient. Vascular leakage leading to edema clearly links to visual impairment and remains an important target for therapy. Despite recent advances in the treatment of DME and DR with anti-VEGFs, effective therapies with new mechanisms of action to address current treatment limitations regarding vessel regeneration and reperfusion of ischemic retinal areas are still needed. The Wnt signaling pathway plays a critical role in proper vascular development and maintenance in the retina, and thus provides a novel therapeutic approach for the treatment of diabetic and other retinopathies. In this review, we summarize the potential of this pathway to address treatment gaps with current therapies, its promise as a novel and potentially disease modifying therapy for patients with DR and opportunities in other retinal vascular diseases.
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