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Fan Q, Li H, Wang X, Tham YC, Teo KYC, Yasuda M, Lim WK, Kwan YP, Teo JX, Chen CJ, Chen LJ, Ahn J, Davila S, Miyake M, Tan P, Park KH, Pang CP, Khor CC, Wong TY, Yanagi Y, Cheung CMG, Cheng CY. Contribution of common and rare variants to Asian neovascular age-related macular degeneration subtypes. Nat Commun 2023; 14:5574. [PMID: 37696869 PMCID: PMC10495468 DOI: 10.1038/s41467-023-41256-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2022] [Accepted: 08/28/2023] [Indexed: 09/13/2023] Open
Abstract
Neovascular age-related macular degeneration (nAMD), along with its clinical subtype known as polypoidal choroidal vasculopathy (PCV), are among the leading causes of vision loss in elderly Asians. In a genome-wide association study (GWAS) comprising 3,128 nAMD (1,555 PCV and 1,573 typical nAMD), and 5,493 controls of East Asian ancestry, we identify twelve loci, of which four are novel ([Formula: see text]). Substantial genetic sharing between PCV and typical nAMD is noted (rg = 0.666), whereas collagen extracellular matrix and fibrosis-related pathways are more pronounced for PCV. Whole-exome sequencing in 259 PCV patients revealed functional rare variants burden in collagen type I alpha 1 chain gene (COL1A1; [Formula: see text]) and potential enrichment of functional rare mutations at AMD-associated loci. At the GATA binding protein 5 (GATA5) locus, the most significant GWAS novel loci, the expressions of genes including laminin subunit alpha 5 (Lama5), mitochondrial ribosome associated GTPase 2 (Mtg2), and collagen type IX alpha 3 chain (Col9A3), are significantly induced during retinal angiogenesis and subretinal fibrosis in murine models. Furthermore, retinoic acid increased the expression of LAMA5 and MTG2 in vitro. Taken together, our data provide insights into the genetic basis of AMD pathogenesis in the Asian population.
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Affiliation(s)
- Qiao Fan
- Center for Quantitative Medicine, Duke-NUS Medical School, National University of Singapore, Singapore, Singapore.
- Ophthalmology & Visual Sciences Academic Clinical Program (Eye ACP), Duke-NUS Medical School, Singapore, Singapore.
| | - Hengtong Li
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
- Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
- Centre for Innovation and Precision Eye Health, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Xiaomeng Wang
- Ophthalmology & Visual Sciences Academic Clinical Program (Eye ACP), Duke-NUS Medical School, Singapore, Singapore
- Center for Vision Research, Duke-NUS Medical School, National University of Singapore, Singapore, Singapore
| | - Yih-Chung Tham
- Ophthalmology & Visual Sciences Academic Clinical Program (Eye ACP), Duke-NUS Medical School, Singapore, Singapore
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
- Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
- Centre for Innovation and Precision Eye Health, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Kelvin Yi Chong Teo
- Ophthalmology & Visual Sciences Academic Clinical Program (Eye ACP), Duke-NUS Medical School, Singapore, Singapore
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
| | - Masayuki Yasuda
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, Miyagi, Japan
| | - Weng Khong Lim
- SingHealth Duke-NUS Institute of Precision Medicine, Singapore, Singapore
- SingHealth Duke-NUS Genomic Medicine Centre, Singapore, Singapore
- Cancer and Stem Cell Biology Program, Duke-NUS Medical School, Singapore, Singapore
- Laboratory of Genome Variation Analytics, Genome Institute of Singapore, Agency for Science, Technology and Research, Singapore, Singapore
| | - Yuet Ping Kwan
- Ophthalmology & Visual Sciences Academic Clinical Program (Eye ACP), Duke-NUS Medical School, Singapore, Singapore
| | - Jing Xian Teo
- SingHealth Duke-NUS Institute of Precision Medicine, Singapore, Singapore
| | - Ching-Jou Chen
- Center for Vision Research, Duke-NUS Medical School, National University of Singapore, Singapore, Singapore
| | - Li Jia Chen
- Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Jeeyun Ahn
- Department of Ophthalmology, Seoul National University College of Medicine, Seoul Metropolitan Government Seoul National University Boramae Medical Center, Seoul, Korea
| | - Sonia Davila
- SingHealth Duke-NUS Institute of Precision Medicine, Singapore, Singapore
| | - Masahiro Miyake
- Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Patrick Tan
- SingHealth Duke-NUS Institute of Precision Medicine, Singapore, Singapore
- Cancer and Stem Cell Biology Program, Duke-NUS Medical School, Singapore, Singapore
- Human Genetics, Genome Institute of Singapore, Singapore, Singapore
| | - Kyu Hyung Park
- Department of Ophthalmology, Seoul National University Hospital, Seoul, Korea
| | - Chi Pui Pang
- Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Chiea Chuan Khor
- Human Genetics, Genome Institute of Singapore, Singapore, Singapore
| | - Tien Yin Wong
- Tsinghua Medicine, Tsinghua University, Beijing, China
| | - Yasuo Yanagi
- Department of Ophthalmology and Microtechnology, Yokohama City University, Yokohama, Japan
| | - Chui Ming Gemmy Cheung
- Ophthalmology & Visual Sciences Academic Clinical Program (Eye ACP), Duke-NUS Medical School, Singapore, Singapore
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
| | - Ching-Yu Cheng
- Ophthalmology & Visual Sciences Academic Clinical Program (Eye ACP), Duke-NUS Medical School, Singapore, Singapore.
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore.
- Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.
- Centre for Innovation and Precision Eye Health, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.
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2
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Guo Y, Gan D, Hu F, Cheng Y, Yu J, Lei B, Shu Q, Gu R, Xu G. Intravitreal injection of mitochondrial DNA induces cell damage and retinal dysfunction in rats. Biol Res 2022; 55:22. [PMID: 35659309 PMCID: PMC9164539 DOI: 10.1186/s40659-022-00390-6] [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: 12/13/2021] [Accepted: 05/03/2022] [Indexed: 11/28/2022] Open
Abstract
Background Retinal neurodegeneration is induced by a variety of environmental insults and stresses, but the exact mechanisms are unclear. In the present study, we explored the involvement of cytosolic mitochondrial DNA (mtDNA), resulting in the cGAS-STING dependent inflammatory response and apoptosis in retinal damage in vivo. Methods Retinal injury was induced with white light or intravitreal injection of lipopolysaccharide (LPS). After light- or LPS-induced injury, the amount of cytosolic mtDNA in the retina was detected by PCR. The mtDNA was isolated and used to transfect retinas in vivo. WB and real-time PCR were used to evaluate the activation of cGAS-STING pathway and the levels of apoptosis-associated protein at different times after mtDNA injection. Retinal cell apoptosis rate was detected by TUNEL staining. Full-field electroretinography (ERG) was used to assess the retinal function. Results Light injury and the intravitreal injection of LPS both caused the leakage of mtDNA into the cytoplasm in retinal tissue. After the transfection of mtDNA in vivo, the levels of cGAS, STING, and IFN-β mRNAs and the protein levels of STING, phosph-TBK1, phospho-IRF3, and IFN-β were upregulated. mtDNA injection also induced the activation of caspase 3 and caspase 9. BAX and BAK were increased at both the mRNA and protein levels. The release of cytochrome c from the mitochondria to the cytosol was increased after mtDNA injection. The wave amplitudes on ERG decreased and retinal cell apoptosis was detected after mtDNA injection. Conclusions Cytosolic mtDNA triggers an inflammatory response. It also promotes apoptosis and the dysfunction of the retina. Supplementary Information The online version contains supplementary material available at 10.1186/s40659-022-00390-6.
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Ye SS, Tang Y, Song JT. ATP and Adenosine in the Retina and Retinal Diseases. Front Pharmacol 2021; 12:654445. [PMID: 34211393 PMCID: PMC8239296 DOI: 10.3389/fphar.2021.654445] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2021] [Accepted: 05/25/2021] [Indexed: 12/11/2022] Open
Abstract
Extracellular ATP and its ultimate degradation product adenosine are potent extracellular signaling molecules that elicit a variety of pathophysiological pathways in retina through the activation of P2 and P1 purinoceptors, respectively. Excessive build-up of extracellular ATP accelerates pathologic responses in retinal diseases, whereas accumulation of adenosine protects retinal cells against degeneration or inflammation. This mini-review focuses on the roles of ATP and adenosine in three types of blinding diseases including age-related macular degeneration (AMD), glaucoma, and diabetic retinopathy (DR). Several agonists and antagonists of ATP receptors and adenosine receptors (ARs) have been developed for the potential treatment of glaucoma, DR and AMD: antagonists of P2X7 receptor (P2X7R) (BBG, MRS2540) prevent ATP-induced neuronal apoptosis in glaucoma, DR, and AMD; A1 receptor (A1R) agonists (INO-8875) lower intraocular pressure in glaucoma; A2A receptor (A2AR) agonists (CGS21680) or antagonists (SCH58261, ZM241385) reduce neuroinflammation in glaucoma, DR, and AMD; A3 receptor (A3R) agonists (2-Cl-lB-MECA, MRS3558) protect retinal ganglion cells (RGCs) from apoptosis in glaucoma.
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Affiliation(s)
- Shan-Shan Ye
- Eye Hospital, China Academy of Chinese Medical Sciences, Beijing, China
| | - Yong Tang
- International Collaborative Centre on Big Science Plan for Purinergic Signalling, Chengdu University of Traditional Chinese Medicine, Chengdu, China.,Acupuncture and Chronobiology Key Laboratory of Sichuan Province, Chengdu, China
| | - Jian-Tao Song
- Eye Hospital, China Academy of Chinese Medical Sciences, Beijing, China
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4
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Retinal Inflammation, Cell Death and Inherited Retinal Dystrophies. Int J Mol Sci 2021; 22:ijms22042096. [PMID: 33672611 PMCID: PMC7924201 DOI: 10.3390/ijms22042096] [Citation(s) in RCA: 56] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 02/12/2021] [Accepted: 02/18/2021] [Indexed: 12/15/2022] Open
Abstract
Inherited retinal dystrophies (IRDs) are a group of retinal disorders that cause progressive and severe loss of vision because of retinal cell death, mainly photoreceptor cells. IRDs include retinitis pigmentosa (RP), the most common IRD. IRDs present a genetic and clinical heterogeneity that makes it difficult to achieve proper treatment. The progression of IRDs is influenced, among other factors, by the activation of the immune cells (microglia, macrophages, etc.) and the release of inflammatory molecules such as chemokines and cytokines. Upregulation of tumor necrosis factor alpha (TNFα), a pro-inflammatory cytokine, is found in IRDs. This cytokine may influence photoreceptor cell death. Different cell death mechanisms are proposed, including apoptosis, necroptosis, pyroptosis, autophagy, excessive activation of calpains, or parthanatos for photoreceptor cell death. Some of these cell death mechanisms are linked to TNFα upregulation and inflammation. Therapeutic approaches that reduce retinal inflammation have emerged as useful therapies for slowing down the progression of IRDs. We focused this review on the relationship between retinal inflammation and the different cell death mechanisms involved in RP. We also reviewed the main anti-inflammatory therapies for the treatment of IRDs.
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5
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Calzaferri F, Ruiz-Ruiz C, de Diego AMG, de Pascual R, Méndez-López I, Cano-Abad MF, Maneu V, de Los Ríos C, Gandía L, García AG. The purinergic P2X7 receptor as a potential drug target to combat neuroinflammation in neurodegenerative diseases. Med Res Rev 2020; 40:2427-2465. [PMID: 32677086 DOI: 10.1002/med.21710] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Revised: 06/22/2020] [Accepted: 06/27/2020] [Indexed: 12/25/2022]
Abstract
Neurodegenerative diseases (NDDs) represent a huge social burden, particularly in Alzheimer's disease (AD) in which all proposed treatments investigated in murine models have failed during clinical trials (CTs). Thus, novel therapeutic strategies remain crucial. Neuroinflammation is a common pathogenic feature of NDDs. As purinergic P2X7 receptors (P2X7Rs) are gatekeepers of inflammation, they could be developed as drug targets for NDDs. Herein, we review this challenging hypothesis and comment on the numerous studies that have investigated P2X7Rs, emphasizing their molecular structure and functions, as well as their role in inflammation. Then, we elaborate on research undertaken in the field of medicinal chemistry to determine potential P2X7R antagonists. Subsequently, we review the state of neuroinflammation and P2X7R expression in the brain, in animal models and patients suffering from AD, Parkinson's disease, amyotrophic lateral sclerosis, Huntington's disease, multiple sclerosis, and retinal degeneration. Next, we summarize the in vivo studies testing the hypothesis that by mitigating neuroinflammation, P2X7R blockers afford neuroprotection, increasing neuroplasticity and neuronal repair in animal models of NDDs. Finally, we reviewed previous and ongoing CTs investigating compounds directed toward targets associated with NDDs; we propose that CTs with P2X7R antagonists should be initiated. Despite the high expectations for putative P2X7Rs antagonists in various central nervous system diseases, the field is moving forward at a relatively slow pace, presumably due to the complexity of P2X7Rs. A better pharmacological approach to combat NDDs would be a dual strategy, combining P2X7R antagonism with drugs targeting a selective pathway in a given NDD.
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Affiliation(s)
- Francesco Calzaferri
- Departamento de Farmacología, Instituto-Fundación Teófilo Hernando, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
| | - Cristina Ruiz-Ruiz
- Departamento de Farmacología, Instituto-Fundación Teófilo Hernando, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
| | - Antonio M G de Diego
- Departamento de Farmacología, Instituto-Fundación Teófilo Hernando, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain.,Instituto de Investigación Sanitaria, Hospital Universitario de La Princesa, Universidad Autónoma de Madrid, Madrid, Spain
| | - Ricardo de Pascual
- Departamento de Farmacología, Instituto-Fundación Teófilo Hernando, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
| | - Iago Méndez-López
- Departamento de Farmacología, Instituto-Fundación Teófilo Hernando, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
| | - María F Cano-Abad
- Departamento de Farmacología, Instituto-Fundación Teófilo Hernando, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain.,Instituto de Investigación Sanitaria, Hospital Universitario de La Princesa, Universidad Autónoma de Madrid, Madrid, Spain
| | - Victoria Maneu
- Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante, San Vicente del Raspeig, Spain
| | - Cristóbal de Los Ríos
- Departamento de Farmacología, Instituto-Fundación Teófilo Hernando, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain.,Instituto de Investigación Sanitaria, Hospital Universitario de La Princesa, Universidad Autónoma de Madrid, Madrid, Spain
| | - Luis Gandía
- Departamento de Farmacología, Instituto-Fundación Teófilo Hernando, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
| | - Antonio G García
- Departamento de Farmacología, Instituto-Fundación Teófilo Hernando, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain.,Instituto de Investigación Sanitaria, Hospital Universitario de La Princesa, Universidad Autónoma de Madrid, Madrid, Spain
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6
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Hu CB, Sui BD, Wang BY, Li G, Hu CH, Zheng CX, Du FY, Zhu CH, Li HB, Feng Y, Jin Y, Yu XR. NDRG2 suppression as a molecular hallmark of photoreceptor-specific cell death in the mouse retina. Cell Death Discov 2018; 4:32. [PMID: 30245855 PMCID: PMC6135825 DOI: 10.1038/s41420-018-0101-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Accepted: 08/23/2018] [Indexed: 02/07/2023] Open
Abstract
Photoreceptor cell death is recognized as the key pathogenesis of retinal degeneration, but the molecular basis underlying photoreceptor-specific cell loss in retinal damaging conditions is virtually unknown. The N-myc downstream regulated gene (NDRG) family has recently been reported to regulate cell viability, in particular NDRG1 has been uncovered expression in photoreceptor cells. Accordingly, we herein examined the potential roles of NDRGs in mediating photoreceptor-specific cell loss in retinal damages. By using mouse models of retinal degeneration and the 661 W photoreceptor cell line, we showed that photoreceptor cells are indeed highly sensitive to light exposure and the related oxidative stress, and that photoreceptor cells are even selectively diminished by phototoxins of the alkylating agent N-Methyl-N-nitrosourea (MNU). Unexpectedly, we discovered that of all the NDRG family members, NDRG2, but not the originally hypothesized NDRG1 or other NDRG subtypes, was selectively expressed and specifically responded to retinal damaging conditions in photoreceptor cells. Furthermore, functional experiments proved that NDRG2 was essential for photoreceptor cell viability, which could be attributed to NDRG2 control of the photo-oxidative stress, and that it was the suppression of NDRG2 which led to photoreceptor cell loss in damaging conditions. More importantly, NDRG2 preservation contributed to photoreceptor-specific cell maintenance and retinal protection both in vitro and in vivo. Our findings revealed a previously unrecognized role of NDRG2 in mediating photoreceptor cell homeostasis and established for the first time the molecular hallmark of photoreceptor-specific cell death as NDRG2 suppression, shedding light on improved understanding and therapy of retinal degeneration.
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Affiliation(s)
- Cheng-Biao Hu
- 1Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, 710061 Xi'an, Shaanxi China.,2Key Laboratory of Environment and Genes Related to Diseases (Xi'an Jiaotong University), Ministry of Education, Xi'an, Shaanxi Sheng China
| | - Bing-Dong Sui
- 3State Key Laboratory of Military Stomatology, Center for Tissue Engineering, Fourth Military Medical University, 710032 Xi'an, Shaanxi China.,Xi'an Institute of Tissue Engineering and Regenerative Medicine, 710032 Xi'an, Shaanxi China
| | - Bao-Ying Wang
- 1Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, 710061 Xi'an, Shaanxi China.,2Key Laboratory of Environment and Genes Related to Diseases (Xi'an Jiaotong University), Ministry of Education, Xi'an, Shaanxi Sheng China
| | - Gao Li
- Xi'an Institute of Tissue Engineering and Regenerative Medicine, 710032 Xi'an, Shaanxi China.,5Department of Stomatology, The People's Hospital of Zhangqiu City, 250200 Zhangqiu, Shandong China
| | - Cheng-Hu Hu
- 3State Key Laboratory of Military Stomatology, Center for Tissue Engineering, Fourth Military Medical University, 710032 Xi'an, Shaanxi China.,Xi'an Institute of Tissue Engineering and Regenerative Medicine, 710032 Xi'an, Shaanxi China
| | - Chen-Xi Zheng
- 3State Key Laboratory of Military Stomatology, Center for Tissue Engineering, Fourth Military Medical University, 710032 Xi'an, Shaanxi China.,Xi'an Institute of Tissue Engineering and Regenerative Medicine, 710032 Xi'an, Shaanxi China
| | - Fang-Ying Du
- 1Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, 710061 Xi'an, Shaanxi China.,2Key Laboratory of Environment and Genes Related to Diseases (Xi'an Jiaotong University), Ministry of Education, Xi'an, Shaanxi Sheng China
| | - Chun-Hui Zhu
- 1Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, 710061 Xi'an, Shaanxi China.,2Key Laboratory of Environment and Genes Related to Diseases (Xi'an Jiaotong University), Ministry of Education, Xi'an, Shaanxi Sheng China
| | - Hong-Bo Li
- 1Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, 710061 Xi'an, Shaanxi China.,2Key Laboratory of Environment and Genes Related to Diseases (Xi'an Jiaotong University), Ministry of Education, Xi'an, Shaanxi Sheng China
| | - Yan Feng
- 1Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, 710061 Xi'an, Shaanxi China.,2Key Laboratory of Environment and Genes Related to Diseases (Xi'an Jiaotong University), Ministry of Education, Xi'an, Shaanxi Sheng China
| | - Yan Jin
- 3State Key Laboratory of Military Stomatology, Center for Tissue Engineering, Fourth Military Medical University, 710032 Xi'an, Shaanxi China.,Xi'an Institute of Tissue Engineering and Regenerative Medicine, 710032 Xi'an, Shaanxi China
| | - Xiao-Rui Yu
- 1Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, 710061 Xi'an, Shaanxi China.,2Key Laboratory of Environment and Genes Related to Diseases (Xi'an Jiaotong University), Ministry of Education, Xi'an, Shaanxi Sheng China
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7
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Wang B, Hu C, Yang X, Du F, Feng Y, Li H, Zhu C, Yu X. Inhibition of GSK-3β Activation Protects SD Rat Retina Against N-Methyl-N-Nitrosourea-Induced Degeneration by Modulating the Wnt/β-Catenin Signaling Pathway. J Mol Neurosci 2017; 63:233-242. [PMID: 28929374 DOI: 10.1007/s12031-017-0973-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Accepted: 09/08/2017] [Indexed: 01/01/2023]
Abstract
Retinal degenerative diseases are characterized by photoreceptor cell loss. Photoreceptor cell loss leading to retinal degeneration can be induced by N-methyl-N-nitrosourea (MNU), which was widely used to mimic the pathology. However, the mechanism by which MNU induces photoreceptor cell loss is still largely unknown. The purpose of the present study was to investigate whether phosphorylation of glycogen synthase kinase-3β (p-GSK-3β) is a potent mediator of MNU-induced retinal degeneration and how p-GSK-3β affects the process. MNU-induced photoreceptor cell loss was evaluated in Sprague-Dawley (SD) rat retinas. GSK-3β and Akt expression levels did not change during MNU-induced retinal degeneration but the phosphorylation of GSK-3β and Akt was decreased by MNU treatment. Lithium chloride (LiCl), which increases p-GSK-3β level and active-β-catenin level, reversed retinal degeneration induced by MNU treatment. These results suggest that GSK-3β activation is closely related to photoreceptor cell loss and that the application of the GSK-3β inhibitor LiCl could activate Wnt/β-catenin signaling pathway and reduce photoreceptor cell loss induced by MNU. Our findings indicate that inhibition of GSK-3β activation may be a potential therapeutic target for retinal degeneration induced by photoreceptor cell loss.
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Affiliation(s)
- Baoying Wang
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an Jiaotong University, Xi'an, Shaanxi, 710061, People's Republic of China
| | - Chenghu Hu
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an Jiaotong University, Xi'an, Shaanxi, 710061, People's Republic of China.,Xi'an Institute of Tissue Engineering and Regenerative Medicine, Xi'an, Shaanxi, 710032, People's Republic of China
| | - Xiaobei Yang
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an Jiaotong University, Xi'an, Shaanxi, 710061, People's Republic of China
| | - Fangying Du
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an Jiaotong University, Xi'an, Shaanxi, 710061, People's Republic of China
| | - Yan Feng
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an Jiaotong University, Xi'an, Shaanxi, 710061, People's Republic of China
| | - Hongbo Li
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an Jiaotong University, Xi'an, Shaanxi, 710061, People's Republic of China
| | - Chunhui Zhu
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an Jiaotong University, Xi'an, Shaanxi, 710061, People's Republic of China
| | - Xiaorui Yu
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an Jiaotong University, Xi'an, Shaanxi, 710061, People's Republic of China. .,Key Laboratory of Environment and Genes Related to Diseases (Xi'an Jiaotong University), Ministry of Education, Xi'an, Shaanxi, 710061, People's Republic of China.
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8
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Ho T, Aplin FP, Jobling AI, Phipps JA, de Iongh RU, Greferath U, Vessey KA, Fletcher EL. Localization and Possible Function of P2X Receptors in Normal and Diseased Retinae. J Ocul Pharmacol Ther 2016; 32:509-517. [DOI: 10.1089/jop.2015.0158] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Affiliation(s)
- Tracy Ho
- Department of Anatomy and Neuroscience, The University of Melbourne, Parkville, Australia
| | - Felix P. Aplin
- Department of Anatomy and Neuroscience, The University of Melbourne, Parkville, Australia
| | - Andrew I. Jobling
- Department of Anatomy and Neuroscience, The University of Melbourne, Parkville, Australia
| | - Joanna A. Phipps
- Department of Anatomy and Neuroscience, The University of Melbourne, Parkville, Australia
| | - Robb U. de Iongh
- Department of Anatomy and Neuroscience, The University of Melbourne, Parkville, Australia
| | - Ursula Greferath
- Department of Anatomy and Neuroscience, The University of Melbourne, Parkville, Australia
| | - Kirstan A. Vessey
- Department of Anatomy and Neuroscience, The University of Melbourne, Parkville, Australia
| | - Erica L. Fletcher
- Department of Anatomy and Neuroscience, The University of Melbourne, Parkville, Australia
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9
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Chavda S, Luthert PJ, Salt TE. P2X 7R modulation of visually evoked synaptic responses in the retina. Purinergic Signal 2016; 12:611-625. [PMID: 27393519 PMCID: PMC5123999 DOI: 10.1007/s11302-016-9522-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2016] [Accepted: 06/24/2016] [Indexed: 10/29/2022] Open
Abstract
P2X7Rs are distributed throughout all layers of the retina, and thus, their localisation on various cell types puts into question their specific site(s) of action. Using a dark-adapted, ex vivo mouse retinal whole mount preparation, the present study aimed to characterise the effect of P2X7R activation on light-evoked, excitatory RGC ON-field excitatory post-synaptic potentials (fEPSPs) and on outer retinal electroretinogram (ERG) responses under comparable conditions. The pharmacologically isolated NMDA receptor-mediated RGC ON-fEPSP was reduced in the presence of BzATP, an effect which was significantly attenuated by A438079 and other selective P2X7R antagonists A804598 or AF27139. In physiological Krebs medium, BzATP induced a significant potentiation of the ERG a-wave, with a concomitant reduction in the b-wave and the power of the oscillatory potentials. Conversely, in the pharmacologically modified Mg2+-free perfusate, BzATP reduced both the a-wave and b-wave. The effects of BzATP on the ERG components were suppressed by A438079. A role for P2X7R function in visual processing in both the inner and outer retina under physiological conditions remains controversial. The ON-fEPSP was significantly reduced in the presence of A804598 but not by A438079 or AF27139. Furthermore, A438079 did not have any effect on the ERG components in physiological Krebs but potentiated and reduced the a-wave and b-wave, respectively, when applied to the pharmacologically modified medium. Therefore, activation of P2X7Rs affects the function in the retinal ON pathway. The presence of a high concentration of extracellular ATP would most likely contribute to the modulation of visual transmission in the retina in the pathophysiological microenvironment.
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Affiliation(s)
- Seetal Chavda
- Visual Neuroscience, UCL Institute of Ophthalmology, London, EC1V 9EL, UK
| | - Philip J Luthert
- Ocular Biology and Therapeutics, UCL Institute of Ophthalmology, London, EC1V 9EL, UK.,NIHR Biomedical Research Centre in Ophthalmology, London, EC1V 9EL, UK
| | - Thomas E Salt
- Visual Neuroscience, UCL Institute of Ophthalmology, London, EC1V 9EL, UK.
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10
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Aplin FP, Vessey KA, Luu CD, Guymer RH, Shepherd RK, Fletcher EL. Retinal Changes in an ATP-Induced Model of Retinal Degeneration. Front Neuroanat 2016; 10:46. [PMID: 27199678 PMCID: PMC4850166 DOI: 10.3389/fnana.2016.00046] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Accepted: 04/11/2016] [Indexed: 11/20/2022] Open
Abstract
In rodents and felines, intravitreal administration of adenosine triphosphate (ATP) has been shown to induce photoreceptor death providing a tractable model of retinal degeneration in these species. This study investigated the long term effects of photoreceptor loss in an ATP induced feline model of retinal degeneration. Six normal sighted felines were unilaterally blinded using intravitreal ATP injections and assessed using electroretinography (ERG) and optical coherence tomography (OCT). At 30 h (n = 3) or 12 weeks (n = 3) post-injection, the animals were euthanized and the eyes enucleated. Retinae were sectioned and labeled using immunohistochemistry for markers of cell death, neural remodeling and gliosis. Ongoing cell death and retinal degeneration was observed in the outer retina at both 30 h and 12 weeks following unilateral ATP injection. Markers of mid to late-stage retinal remodeling such as cell displacement and aberrant neurite growth were observed in the inner retina at 12 weeks post-injection. Ganglion cells appeared to remain intact in ATP injected eyes. Müller cell gliosis was observed throughout the inner and outer retina, in some parts completely enveloping and/or displacing the surviving neural tissue. Our data suggests that the ATP injected feline retina continues to undergo progressive retinal degeneration and exhibits abnormalities consistent with a description of retinal remodeling commonly seen in other models of retinal degeneration. These findings validate the use of intravitreal ATP injection in feline as a large animal model of retinal degeneration which may aid in development of therapies aiming to restore visual function after photoreceptor degeneration.
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Affiliation(s)
- Felix P Aplin
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, East MelbourneMelbourne, VIC, Australia; Department of Anatomy and Neuroscience, The University of MelbourneMelbourne, VIC, Australia; The Bionics Institute, East MelbourneMelbourne, VIC, Australia
| | - Kirstan A Vessey
- Department of Anatomy and Neuroscience, The University of Melbourne Melbourne, VIC, Australia
| | - Chi D Luu
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, East MelbourneMelbourne, VIC, Australia; Department of Surgery (Ophthalmology), The University of MelbourneParkville, VIC, Australia
| | - Robyn H Guymer
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, East MelbourneMelbourne, VIC, Australia; Department of Surgery (Ophthalmology), The University of MelbourneParkville, VIC, Australia
| | - Robert K Shepherd
- The Bionics Institute, East MelbourneMelbourne, VIC, Australia; Medical Bionics Department, The University of MelbourneMelbourne, VIC, Australia
| | - Erica L Fletcher
- Department of Anatomy and Neuroscience, The University of Melbourne Melbourne, VIC, Australia
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11
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A Naturally-Derived Compound Schisandrin B Enhanced Light Sensation in the pde6c Zebrafish Model of Retinal Degeneration. PLoS One 2016; 11:e0149663. [PMID: 26930483 PMCID: PMC4773124 DOI: 10.1371/journal.pone.0149663] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2015] [Accepted: 02/03/2016] [Indexed: 11/19/2022] Open
Abstract
Retinal degeneration is often progressive. This feature has provided a therapeutic window for intervention that may extend functional vision in patients. Even though this approach is feasible, few promising drug candidates are available. The scarcity of new drugs has motivated research to discover novel compounds through different sources. One such example is Schisandrin B (SchB), an active component isolated from the five-flavor fruit (Fructus Schisandrae) that is postulated in traditional Chinese medicines to exert prophylactic visual benefit. This SchB benefit was investigated in this study in pde6cw59, a zebrafish retinal-degeneration model. In this model, the pde6c gene (phosphodiesterase 6C, cGMP-specific, cone, alpha prime) carried a mutation which caused cone degeneration. This altered the local environment and caused the bystander rods to degenerate too. To test SchB on the pde6cw59 mutants, a treatment concentration was first determined that would not cause morphological defects, and would initiate known physiological response. Then, the mutants were treated with the optimized SchB concentration before the appearance of retinal degeneration at 3 days postfertilization (dpf). The light sensation of animals was evaluated at 6 dpf by the visual motor response (VMR), a visual startle that could be initiated by drastic light onset and offset. The results show that the VMR of pde6cw59 mutants towards light onset was enhanced by the SchB treatment, and that the initial phase of the enhancement was primarily mediated through the mutants’ eyes. Further immunostaining analysis indicates that the treatment specifically reduced the size of the abnormally large rods. These observations implicate an interesting hypothesis: that the morphologically-improved rods drive the observed VMR enhancement. Together, these investigations have identified a possible visual benefit of SchB on retinal degeneration, a benefit that can potentially be further developed to extend functional vision in patients.
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12
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Corso L, Cavallero A, Baroni D, Garbati P, Prestipino G, Bisti S, Nobile M, Picco C. Saffron reduces ATP-induced retinal cytotoxicity by targeting P2X7 receptors. Purinergic Signal 2016; 12:161-74. [PMID: 26739703 DOI: 10.1007/s11302-015-9490-3] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Accepted: 12/15/2015] [Indexed: 11/25/2022] Open
Abstract
P2X7-type purinergic receptors are distributed throughout the nervous system where they contribute to physiological and pathological functions. In the retina, this receptor is found in both inner and outer cells including microglia modulating signaling and health of retinal cells. It is involved in retinal neurodegenerative disorders such as retinitis pigmentosa and age-related macular degeneration (AMD). Experimental studies demonstrated that saffron protects photoreceptors from light-induced damage preserving both retinal morphology and visual function and improves retinal flicker sensitivity in AMD patients. To evaluate a possible interaction between saffron and P2X7 receptors (P2X7Rs), different cellular models and experimental approaches were used. We found that saffron positively influences the viability of mouse primary retinal cells and photoreceptor-derived 661W cells exposed to ATP, and reduced the ATP-induced intracellular calcium increase in 661W cells. Similar results were obtained on HEK cells transfected with recombinant rat P2X7R but not on cells transfected with rat P2X2R. Finally, patch-clamp experiments showed that saffron inhibited cationic currents in HEK-P2X7R cells. These results point out a novel mechanism through which saffron may exert its protective role in neurodegeneration and support the idea that P2X7-mediated calcium signaling may be a crucial therapeutic target in the treatment of neurodegenerative diseases.
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Affiliation(s)
- Lucia Corso
- National Research Council, Institute of Biophysics, Via De Marini 6, 16149, Genoa, Italy.,Department of Biotechnology and Applied clinical Science, DISCAB, University of L'Aquila, L'Aquila, Italy
| | - Anna Cavallero
- National Research Council, Institute of Biophysics, Via De Marini 6, 16149, Genoa, Italy
| | - Debora Baroni
- National Research Council, Institute of Biophysics, Via De Marini 6, 16149, Genoa, Italy
| | - Patrizia Garbati
- National Research Council, Institute of Biophysics, Via De Marini 6, 16149, Genoa, Italy
| | - Gianfranco Prestipino
- National Research Council, Institute of Biophysics, Via De Marini 6, 16149, Genoa, Italy
| | - Silvia Bisti
- Department of Biotechnology and Applied clinical Science, DISCAB, University of L'Aquila, L'Aquila, Italy
| | - Mario Nobile
- National Research Council, Institute of Biophysics, Via De Marini 6, 16149, Genoa, Italy
| | - Cristiana Picco
- National Research Council, Institute of Biophysics, Via De Marini 6, 16149, Genoa, Italy.
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13
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Giblin JP, Comes N, Strauss O, Gasull X. Ion Channels in the Eye: Involvement in Ocular Pathologies. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2015; 104:157-231. [PMID: 27038375 DOI: 10.1016/bs.apcsb.2015.11.006] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The eye is the sensory organ of vision. There, the retina transforms photons into electrical signals that are sent to higher brain areas to produce visual sensations. In the light path to the retina, different types of cells and tissues are involved in maintaining the transparency of avascular structures like the cornea or lens, while others, like the retinal pigment epithelium, have a critical role in the maintenance of photoreceptor function by regenerating the visual pigment. Here, we have reviewed the roles of different ion channels expressed in ocular tissues (cornea, conjunctiva and neurons innervating the ocular surface, lens, retina, retinal pigment epithelium, and the inflow and outflow systems of the aqueous humor) that are involved in ocular disease pathophysiologies and those whose deletion or pharmacological modulation leads to specific diseases of the eye. These include pathologies such as retinitis pigmentosa, macular degeneration, achromatopsia, glaucoma, cataracts, dry eye, or keratoconjunctivitis among others. Several disease-associated ion channels are potential targets for pharmacological intervention or other therapeutic approaches, thus highlighting the importance of these channels in ocular physiology and pathophysiology.
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Affiliation(s)
- Jonathan P Giblin
- Universitat de Barcelona, Barcelona, Spain; Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | - Nuria Comes
- Universitat de Barcelona, Barcelona, Spain; Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | | | - Xavier Gasull
- Universitat de Barcelona, Barcelona, Spain; Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain.
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14
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Two-photon microscopy reveals early rod photoreceptor cell damage in light-exposed mutant mice. Proc Natl Acad Sci U S A 2014; 111:E1428-37. [PMID: 24706832 DOI: 10.1073/pnas.1317986111] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Atrophic age-related and juvenile macular degeneration are especially devastating due to lack of an effective cure. Two retinal cell types, photoreceptor cells and the adjacent retinal pigmented epithelium (RPE), reportedly display the earliest pathological changes. Abca4(-/-)Rdh8(-/-) mice, which mimic many features of human retinal degeneration, allowed us to determine the sequence of light-induced events leading to retinal degeneration. Using two-photon microscopy with 3D reconstruction methodology, we observed an initial strong retinoid-derived fluorescence and expansion of Abca4(-/-)Rdh8(-/-) mouse rod cell outer segments accompanied by macrophage infiltration after brief exposure of the retina to bright light. Additionally, light-dependent fluorescent compounds produced in rod outer segments were not transferred to the RPE of mice genetically defective in RPE phagocytosis. Collectively, these findings suggest that for light-induced retinopathies in mice, rod photoreceptors are the primary site of toxic retinoid accumulation and degeneration, followed by secondary changes in the RPE.
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15
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Carroll J, Kay DB, Scoles D, Dubra A, Lombardo M. Adaptive optics retinal imaging--clinical opportunities and challenges. Curr Eye Res 2013; 38:709-21. [PMID: 23621343 PMCID: PMC4031042 DOI: 10.3109/02713683.2013.784792] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The array of therapeutic options available to clinicians for treating retinal disease is expanding. With these advances comes the need for better understanding of the etiology of these diseases on a cellular level as well as improved non-invasive tools for identifying the best candidates for given therapies and monitoring the efficacy of those therapies. While spectral domain optical coherence tomography offers a widely available tool for clinicians to assay the living retina, it suffers from poor lateral resolution due to the eye's monochromatic aberrations. Ophthalmic adaptive optics (AO) is a technique to compensate for the eye's aberrations and provide nearly diffraction-limited resolution. The result is the ability to visualize the living retina with cellular resolution. While AO is unquestionably a powerful research tool, many clinicians remain undecided on the clinical potential of AO imaging - putting many at a crossroads with respect to adoption of this technology. This review will briefly summarize the current state of AO retinal imaging, discuss current as well as future clinical applications of AO retinal imaging, and finally provide some discussion of research needs to facilitate more widespread clinical use.
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Affiliation(s)
- Joseph Carroll
- Department of Ophthalmology, Medical College of Wisconsin, Milwaukee, WI, USA.
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16
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Gu BJ, Baird PN, Vessey KA, Skarratt KK, Fletcher EL, Fuller SJ, Richardson AJ, Guymer RH, Wiley JS. A rare functional haplotype of the
P2RX4
and
P2RX7
genes leads to loss of innate phagocytosis and confers increased risk of age‐related macular degeneration. FASEB J 2013; 27:1479-87. [DOI: 10.1096/fj.12-215368] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Ben J. Gu
- Florey Institute of Neuroscience and Mental HealthUniversity of MelbourneParkvilleVictoriaAustralia
| | - Paul N. Baird
- Centre for Eye Research AustraliaUniversity of MelbourneRoyal Victorian Eye and Ear HospitalEast MelbourneVictoriaAustralia
| | - Kirstan A. Vessey
- Department of Anatomy and NeuroscienceUniversity of MelbourneParkvilleVictoriaAustralia
| | - Kristen K. Skarratt
- Nepean Clinical SchoolUniversity of SydneyNepean HospitalPenrithNew South WalesAustralia
| | - Erica L. Fletcher
- Department of Anatomy and NeuroscienceUniversity of MelbourneParkvilleVictoriaAustralia
| | - Stephen J. Fuller
- Nepean Clinical SchoolUniversity of SydneyNepean HospitalPenrithNew South WalesAustralia
| | - Andrea J. Richardson
- Centre for Eye Research AustraliaUniversity of MelbourneRoyal Victorian Eye and Ear HospitalEast MelbourneVictoriaAustralia
| | - Robyn H. Guymer
- Centre for Eye Research AustraliaUniversity of MelbourneRoyal Victorian Eye and Ear HospitalEast MelbourneVictoriaAustralia
| | - James S. Wiley
- Florey Institute of Neuroscience and Mental HealthUniversity of MelbourneParkvilleVictoriaAustralia
- Nepean Clinical SchoolUniversity of SydneyNepean HospitalPenrithNew South WalesAustralia
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17
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Mooney I, LaMotte J. Emerging options for the management of age-related macular degeneration with stem cells. Stem Cells Cloning 2010; 4:1-10. [PMID: 24198525 PMCID: PMC3781754 DOI: 10.2147/sccaa.s7674] [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] [Indexed: 11/23/2022] Open
Abstract
Age-related macular degeneration (AMD) is a devastating retinal disease that occurs in later life as the retinal pigment epithelium (RPE) cells die, with subsequent photoreceptor degeneration. In the past, RPE transplant surgeries gave evidence that AMD was potentially treatable, but it involved limited amounts of ocular tissue, and the complication rate was high. Then, stem cell transplants offered an unlimited supply of retinal precursors for endogenous repair and exogenous cell replacement. Debate continues as to which type of stem cell is most appropriate for treating AMD. The prospects include adult-derived progenitor stem cells (including progenitor cells from ocular tissues), hematopoietic stem cells, embryonic stem cells, and induced pluripotent stem cells. Now the therapy is expanding into phase I human trials. This review examines the collective research contributions toward a clinical model of AMD management with stem cells.
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Affiliation(s)
| | - James LaMotte
- Department of Basic and Visual Science, Southern California College of Optometry, Fullerton, CA, USA
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