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Xu L, Xu Y, Jiang Y, Jiang J, Chen S, Sun D, Li S, Wei F, Zhu H. IP3R2 regulates apoptosis by Ca2+ transfer through mitochondria-ER contacts in hypoxic photoreceptor injury. Exp Eye Res 2024; 245:109965. [PMID: 38851477 DOI: 10.1016/j.exer.2024.109965] [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: 12/22/2023] [Revised: 06/04/2024] [Accepted: 06/05/2024] [Indexed: 06/10/2024]
Abstract
Mitochondria-associated ER membranes (MAMs) are contact sites that enable bidirectional communication between the ER (endoplasmic reticulum) and mitochondria, including the transfer of Ca2+ signals. MAMs are essential for mitochondrial function and cellular energy metabolism. However, unrestrained Ca2+ transfer to the mitochondria can lead to mitochondria-dependent apoptosis. IP3R2 (Inositol 1,4,5-trisphosphate receptor 2) is an important intracellular Ca2+ channel. This study investigated the contribution of IP3R2-MAMs to hypoxia-induced apoptosis in photoreceptor cells. A photoreceptor hypoxia model was established by subretinal injection of hyaluronic acid (1%) in C57BL/6 mice and 1% O2 treatment in 661W cells. Transmission electron microscopy (TEM), ER-mitochondria colocalization, and the MAM reporter were utilized to evaluate MAM alterations. Cell apoptosis and mitochondrial homeostasis were evaluated using immunofluorescence (IF), flow cytometry, western blotting (WB), and ATP assays. SiRNA transfection was employed to silence IP3R2 in 661W cells. Upon hypoxia induction, MAMs were significantly increased in photoreceptors both in vivo and in vitro. This was accompanied by the activation of mitochondrial apoptosis and disruption of mitochondrial homeostasis. Elevated MAM-enriched IP3R2 protein levels induced by hypoxic injury led to mitochondrial calcium overload and subsequent photoreceptor apoptosis. Notably, IP3R2 knockdown not only improved mitochondrial morphology but also restored mitochondrial function in photoreceptors by limiting MAM formation and thereby attenuating mitochondrial calcium overload under hypoxia. Our results suggest that IP3R2-MAM-mediated mitochondrial calcium overload plays a critical role in mitochondrial dyshomeostasis, ultimately contributing to photoreceptor cell death. Targeting MAM constitutive proteins might provide an option for a therapeutic approach to mitigate photoreceptor death in retinal detachment.
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Affiliation(s)
- Li Xu
- Department of Ophthalmology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yihua Xu
- Department of Ophthalmology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yaoxu Jiang
- School of Health Science and Engineering, University of Shanghai for Science and Technology, Shanghai, China
| | - Jingjing Jiang
- Department of Ophthalmology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Shimei Chen
- Department of Ophthalmology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Dandan Sun
- Department of Ophthalmology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Shenping Li
- Department of Ophthalmology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Fang Wei
- Department of Ophthalmology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; National Clinical Research Center for Eye Diseases, Shanghai Key Laboratory of Ocular Fundus Disease, Shanghai Engineering Center for Visual Science and Photomedicine, Shanghai Engineering Center for Precise Diagnosis and Treatment of Eye Diseases, Shanghai, China.
| | - Hong Zhu
- Department of Ophthalmology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; National Clinical Research Center for Eye Diseases, Shanghai Key Laboratory of Ocular Fundus Disease, Shanghai Engineering Center for Visual Science and Photomedicine, Shanghai Engineering Center for Precise Diagnosis and Treatment of Eye Diseases, Shanghai, China.
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2
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Nolan ND, Cui X, Robbings BM, Demirkol A, Pandey K, Wu WH, Hu HF, Jenny LA, Lin CS, Hass DT, Du J, Hurley JB, Tsang SH. CRISPR editing of anti-anemia drug target rescues independent preclinical models of retinitis pigmentosa. Cell Rep Med 2024; 5:101459. [PMID: 38518771 PMCID: PMC11031380 DOI: 10.1016/j.xcrm.2024.101459] [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: 07/07/2023] [Revised: 12/21/2023] [Accepted: 02/14/2024] [Indexed: 03/24/2024]
Abstract
Retinitis pigmentosa (RP) is one of the most common forms of hereditary neurodegeneration. It is caused by one or more of at least 3,100 mutations in over 80 genes that are primarily expressed in rod photoreceptors. In RP, the primary rod-death phase is followed by cone death, regardless of the underlying gene mutation that drove the initial rod degeneration. Dampening the oxidation of glycolytic end products in rod mitochondria enhances cone survival in divergent etiological disease models independent of the underlying rod-specific gene mutations. Therapeutic editing of the prolyl hydroxylase domain-containing protein gene (PHD2, also known as Egln1) in rod photoreceptors led to the sustained survival of both diseased rods and cones in both preclinical autosomal-recessive and dominant RP models. Adeno-associated virus-mediated CRISPR-based therapeutic reprogramming of the aerobic glycolysis node may serve as a gene-agnostic treatment for patients with various forms of RP.
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Affiliation(s)
- Nicholas D Nolan
- Jonas Children's Vision Care and Bernard & Shirlee Brown Glaucoma Laboratory, Institute of Human Nutrition, Columbia Stem Cell Initiative, New York, NY 10032, USA; Department of Biomedical Engineering, Columbia University, New York, NY 10027, USA; Edward S. Harkness Eye Institute, Columbia University Irving Medical Center, New York-Presbyterian Hospital, New York, NY 10032, USA
| | - Xuan Cui
- Jonas Children's Vision Care and Bernard & Shirlee Brown Glaucoma Laboratory, Institute of Human Nutrition, Columbia Stem Cell Initiative, New York, NY 10032, USA; Edward S. Harkness Eye Institute, Columbia University Irving Medical Center, New York-Presbyterian Hospital, New York, NY 10032, USA
| | - Brian M Robbings
- Department of Biochemistry, The University of Washington, Seattle, WA 98195, USA; Diabetes Institute, The University of Washington, Seattle, WA 98195, USA
| | - Aykut Demirkol
- Jonas Children's Vision Care and Bernard & Shirlee Brown Glaucoma Laboratory, Institute of Human Nutrition, Columbia Stem Cell Initiative, New York, NY 10032, USA; Edward S. Harkness Eye Institute, Columbia University Irving Medical Center, New York-Presbyterian Hospital, New York, NY 10032, USA; Vocational School of Health Services, Uskudar University, 34672 Istanbul, Turkey
| | - Kriti Pandey
- Department of Biochemistry, The University of Washington, Seattle, WA 98195, USA
| | - Wen-Hsuan Wu
- Jonas Children's Vision Care and Bernard & Shirlee Brown Glaucoma Laboratory, Institute of Human Nutrition, Columbia Stem Cell Initiative, New York, NY 10032, USA; Edward S. Harkness Eye Institute, Columbia University Irving Medical Center, New York-Presbyterian Hospital, New York, NY 10032, USA
| | - Hannah F Hu
- Jonas Children's Vision Care and Bernard & Shirlee Brown Glaucoma Laboratory, Institute of Human Nutrition, Columbia Stem Cell Initiative, New York, NY 10032, USA; Department of Biomedical Engineering, Columbia University, New York, NY 10027, USA; Edward S. Harkness Eye Institute, Columbia University Irving Medical Center, New York-Presbyterian Hospital, New York, NY 10032, USA
| | - Laura A Jenny
- Jonas Children's Vision Care and Bernard & Shirlee Brown Glaucoma Laboratory, Institute of Human Nutrition, Columbia Stem Cell Initiative, New York, NY 10032, USA; Edward S. Harkness Eye Institute, Columbia University Irving Medical Center, New York-Presbyterian Hospital, New York, NY 10032, USA
| | - Chyuan-Sheng Lin
- Herbert Irving Comprehensive Cancer Center, Department of Pathology & Cell Biology, Columbia University Irving Medical Center, New York, NY 10032, USA; Departments of Ophthalmology, Pathology & Cell Biology, Vagelos College of Physicians and Surgeons, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Daniel T Hass
- Department of Biochemistry, The University of Washington, Seattle, WA 98195, USA
| | - Jianhai Du
- Department of Ophthalmology and Visual Sciences, West Virginia University, Morgantown, WV 26506, USA; Department of Biochemistry and Molecular Medicine, West Virginia University, Morgantown, WV 26501, USA
| | - James B Hurley
- Department of Biochemistry, The University of Washington, Seattle, WA 98195, USA.
| | - Stephen H Tsang
- Jonas Children's Vision Care and Bernard & Shirlee Brown Glaucoma Laboratory, Institute of Human Nutrition, Columbia Stem Cell Initiative, New York, NY 10032, USA; Department of Biomedical Engineering, Columbia University, New York, NY 10027, USA; Edward S. Harkness Eye Institute, Columbia University Irving Medical Center, New York-Presbyterian Hospital, New York, NY 10032, USA; Departments of Ophthalmology, Pathology & Cell Biology, Vagelos College of Physicians and Surgeons, Columbia University Irving Medical Center, New York, NY 10032, USA.
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3
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Yuan X, Ruan W, Bobrow B, Carmeliet P, Eltzschig HK. Targeting hypoxia-inducible factors: therapeutic opportunities and challenges. Nat Rev Drug Discov 2024; 23:175-200. [PMID: 38123660 DOI: 10.1038/s41573-023-00848-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/06/2023] [Indexed: 12/23/2023]
Abstract
Hypoxia-inducible factors (HIFs) are highly conserved transcription factors that are crucial for adaptation of metazoans to limited oxygen availability. Recently, HIF activation and inhibition have emerged as therapeutic targets in various human diseases. Pharmacologically desirable effects of HIF activation include erythropoiesis stimulation, cellular metabolism optimization during hypoxia and adaptive responses during ischaemia and inflammation. By contrast, HIF inhibition has been explored as a therapy for various cancers, retinal neovascularization and pulmonary hypertension. This Review discusses the biochemical mechanisms that control HIF stabilization and the molecular strategies that can be exploited pharmacologically to activate or inhibit HIFs. In addition, we examine medical conditions that benefit from targeting HIFs, the potential side effects of HIF activation or inhibition and future challenges in this field.
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Affiliation(s)
- Xiaoyi Yuan
- Department of Anaesthesiology, Critical Care and Pain Medicine, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX, USA.
| | - Wei Ruan
- Department of Anaesthesiology, Critical Care and Pain Medicine, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX, USA
- Department of Anaesthesiology, The Second Xiangya Hospital, Central South University, Changsha, China
| | - Bentley Bobrow
- Department of Emergency Medicine, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX, USA
| | - Peter Carmeliet
- Laboratory of Angiogenesis & Vascular Metabolism, Center for Cancer Biology, VIB, Department of Oncology, KU Leuven, Leuven, Belgium
- Laboratory of Angiogenesis & Vascular Heterogeneity, Department of Biomedicine, Aarhus University, Aarhus, Denmark
- Center for Biotechnology, Khalifa University of Science and Technology, Abu Dhabi, United Arab Emirates
| | - Holger K Eltzschig
- Department of Anaesthesiology, Critical Care and Pain Medicine, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX, USA.
- Outcomes Research Consortium, Cleveland, OH, USA.
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Shen J, Chen L, Lv X, Liu N, Miao Y, Zhang Q, Xiao Z, Li M, Yang Y, Liu Z, Chen Q. Emerging Co-Assembled and Sustained Released Natural Medicinal Nanoparticles for Multitarget Therapy of Choroidal Neovascularization. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024:e2314095. [PMID: 38344832 DOI: 10.1002/adma.202314095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2023] [Revised: 01/29/2024] [Indexed: 02/23/2024]
Abstract
Age-related macular degeneration (AMD) disease has become a worldwide senile disease, and frequent intravitreal injection of anti-vascular endothelial growth factor (anti-VEGF) is the mainstream treatment in the clinic, which is associated with sight-threatening complications. Herein, nintedanib, an inhibitor of angiogenesis, and lutein, a potent antioxidant, can co-assemble into nanoparticles through multiple noncovalent interactions. Interestingly, the co-assembled lutein/nintedanib nanoparticles (L/N NPs) exhibit significantly improved stability and achieve long-term sustained release of two drugs for at least two months in mice. Interestingly, in rabbit eyeball with a more complete barrier system, the L/N NPs still successfully distribute in the retina and choroid for a month. In the laser-induced mouse choroidal neovascularization model, the L/N NPs after a minimally invasive subconjunctival administration can successfully inhibit angiogenesis and achieve comparable and even better therapeutic results to that of standard intravitreal injection of anti-VEGF. Therefore, the subconjunctival injection of L/N NPs with long-term sustained drug release behavior represents a promising and innovative strategy for AMD treatment. Such minimally invasive administration together with the ability to effectively inhibit angiogenesis reduce inflammation and counteract oxidative stress and holds great potential for improving patient outcomes and quality of life in those suffering from this debilitating eye condition.
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Affiliation(s)
- Jingjing Shen
- Institute of Functional Nano and Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Soochow University, Suzhou, 215123, China
| | - Linfu Chen
- Institute of Functional Nano and Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Soochow University, Suzhou, 215123, China
| | - Xinying Lv
- Institute of Functional Nano and Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Soochow University, Suzhou, 215123, China
| | - Nanhui Liu
- Institute of Functional Nano and Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Soochow University, Suzhou, 215123, China
| | - Yu Miao
- Institute of Functional Nano and Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Soochow University, Suzhou, 215123, China
| | - Qiang Zhang
- School of Materials Science and Engineering, Tongji University, Shanghai, 201804, China
| | - Zhisheng Xiao
- Institute of Functional Nano and Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Soochow University, Suzhou, 215123, China
| | - Maoyi Li
- Institute of Functional Nano and Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Soochow University, Suzhou, 215123, China
| | - Yang Yang
- School of Materials Science and Engineering, Tongji University, Shanghai, 201804, China
- Department of Thoracic Surgery, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, 200433, P. R. China
- Central Laboratory, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai, 200433, China
| | - Zhuang Liu
- Institute of Functional Nano and Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Soochow University, Suzhou, 215123, China
| | - Qian Chen
- Institute of Functional Nano and Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Soochow University, Suzhou, 215123, China
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Atalor RE, Dieckmann BW, Penn JS, Uddin MDI. Method to Regulate Monocyte Function by Silencing HIF-1α mRNA in a Model of Retinal Neovascularization. ACS APPLIED NANO MATERIALS 2023; 6:22939-22946. [PMID: 38148985 PMCID: PMC10749564 DOI: 10.1021/acsanm.3c04300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Revised: 11/15/2023] [Accepted: 11/17/2023] [Indexed: 12/28/2023]
Abstract
Circulating monocytes migrate into the retina in response to inflammation and neovascularization. Furthermore, under inflammatory conditions such as diabetes, healthy monocytes become activated in the circulation. However, the contribution of activated monocytes to neovascularization is largely unknown. HIF-1α has been shown to contribute to the pathogenesis of neovascularization. We describe here the synthesis of a hybrid nanomaterial for targeted delivery and gene silencing in activated monocytes that are associated with pathological neovascularization. To test the gene silencing ability of AS-shRNA-lipids in vitro, we used the probe to inhibit HIF-1α mRNA induced in mouse monocytes by exposing them to hypoxia. In addition, we tested AS-shRNA-lipids for inhibition of neovascularization in vivo using the mouse model of oxygen-induced retinopathy (OIR). Significant reduction of neovascularization was achieved in mouse OIR by targeting activated monocytes using intraperitoneal injections of AS-shRNA-lipids. Expression of HIF-1α and CD14 mRNA were both inhibited in circulating cells, suggesting normalization of the activated monocytes in P17 OIR animals treated with AS-shRNA-lipids. We hypothesized that inhibition of HIF-1α mRNA in activated monocytes may have a direct impact on VEGF expression in the retinal tissues in vivo. We observed that VEGF mRNA expression was inhibited in P17 retinal tissues after systemic treatment with HIF-1α-targeted AS-shRNA-lipids. These findings may provide a framework for a strategy to inhibit retinal neovascularization by targeting circulating activated monocytes.
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Affiliation(s)
- Rita E. Atalor
- Department
of Ophthalmology and Visual Sciences, Vanderbilt
University School of Medicine, Nashville, Tennessee 37232, United States
| | - Blake W. Dieckmann
- Department
of Ophthalmology and Visual Sciences, Vanderbilt
University School of Medicine, Nashville, Tennessee 37232, United States
| | - John S. Penn
- Department
of Ophthalmology and Visual Sciences, Vanderbilt
University School of Medicine, Nashville, Tennessee 37232, United States
| | - MD Imam Uddin
- Department
of Ophthalmology and Visual Sciences, Vanderbilt
University School of Medicine, Nashville, Tennessee 37232, United States
- Department
of Biomedical Engineering, Vanderbilt University, Nashville, Tennessee 37232, United States
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6
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Henning Y, Willbrand K, Larafa S, Weißenberg G, Matschke V, Theiss C, Görtz GE, Matschke J. Cigarette smoke causes a bioenergetic crisis in RPE cells involving the downregulation of HIF-1α under normoxia. Cell Death Discov 2023; 9:398. [PMID: 37880219 PMCID: PMC10600121 DOI: 10.1038/s41420-023-01695-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Revised: 10/03/2023] [Accepted: 10/16/2023] [Indexed: 10/27/2023] Open
Abstract
Age-related macular degeneration (AMD) is the most common blinding disease in the elderly population. However, there are still many uncertainties regarding the pathophysiology at the molecular level. Currently, impaired energy metabolism in retinal pigment epithelium (RPE) cells is discussed as one major hallmark of early AMD pathophysiology. Hypoxia-inducible factors (HIFs) are important modulators of mitochondrial function. Moreover, smoking is the most important modifiable risk factor for AMD and is known to impair mitochondrial integrity. Therefore, our aim was to establish a cell-based assay that enables us to investigate how smoking affects mitochondrial function in conjunction with HIF signaling in RPE cells. For this purpose, we treated a human RPE cell line with cigarette smoke extract (CSE) under normoxia (21% O2), hypoxia (1% O2), or by co-treatment with Roxadustat, a clinically approved HIF stabilizer. CSE treatment impaired mitochondrial integrity, involving increased mitochondrial reactive oxygen species, disruption of mitochondrial membrane potential, and altered mitochondrial morphology. Treatment effects on cell metabolism were analyzed using a Seahorse Bioanalyzer. Mitochondrial respiration and ATP production were impaired in CSE-treated cells under normoxia. Surprisingly, CSE-treated RPE cells also exhibited decreased glycolytic rate under normoxia, causing a bioenergetic crisis, because two major metabolic pathways that provide ATP were impaired by CSE. Downregulation of glycolytic rate was HIF-dependent because HIF-1α, the α-subunit of HIF-1, was downregulated by CSE on the protein level, especially under normoxia. Moreover, hypoxia incubation and treatment with Roxadustat restored glycolytic flux. Taken together, our in vitro model provides interesting insights into HIF-dependent regulation of glycolysis under normoxic conditions, which will enable us to investigate signaling pathways involved in RPE metabolism in health and disease.
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Affiliation(s)
- Yoshiyuki Henning
- Institute of Physiology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany.
| | - Katrin Willbrand
- Institute of Physiology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Safa Larafa
- Institute of Cell Biology (Cancer Research), University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Gesa Weißenberg
- Institute of Physiology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Veronika Matschke
- Department of Cytology, Institute of Anatomy, Ruhr University Bochum, Bochum, Germany
| | - Carsten Theiss
- Department of Cytology, Institute of Anatomy, Ruhr University Bochum, Bochum, Germany
| | - Gina-Eva Görtz
- Molecular Ophthalmology, Department of Ophthalmology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Johann Matschke
- Institute of Cell Biology (Cancer Research), University Hospital Essen, University of Duisburg-Essen, Essen, Germany
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7
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Jia X, Sun Y, Wang T, Zhong L, Deng J, Zhu X. Mechanism of circular RNA-mediated regulation of L-DOPA to improve wet age-related macular degeneration. Gene 2023; 861:147247. [PMID: 36736867 DOI: 10.1016/j.gene.2023.147247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 01/14/2023] [Accepted: 01/27/2023] [Indexed: 02/04/2023]
Abstract
This study aimed to investigate the effect and mechanism of levodopa (L-DOPA) in the treatment of age-related macular degeneration (AMD). A wet AMD cell model was created via CoCl2 treatment of ARPE-19 cells. The cytoprotective effects of L-DOPA in the model were determined using CCK-8, flow cytometry, TUNEL, qPCR, and ELISA assays. Subsequently, circRNA sequencing and bioinformatics analysis were used to screen differentially expressed circRNAs, which were overexpressed in ARPE-19 cells, to explore their role in wet AMD. The findings revealed that 200 μM CoCl2 treatment inhibited the cell viability and the production of tyrosinase, melanin, and pigment epithelium-derived growth factor but promoted apoptosis and the expression of vascular endothelial growth factor in ARPE-19 cells. Moreover, 20 μM L-DOPA exerted the best therapeutic effect on the model. qPCR showed that Hsa_circ_0018401 (circ-SGMS1) was significantly differentially expressed in each experimental group, which was consistent with the sequencing results. The overexpression of circ-SGMS1 in ARPE-19 cells reversed the effects of CoCl2. Fluorescence in situ hybridization showed that circ-SGMS1 was expressed more in the nucleus than in the cytoplasm. qPCR assays indicated that circ-SGMS1 overexpression did not have a significant effect on the expressions of VEGFA and KDR but significantly reduced the expressions of HIF-1a and THBS1. Circ-SGMS1 is of immense significance in the AMD treatment mechanism of L-DOPA. Overexpression of circ-SGMS1 may alleviate wet AMD by inhibiting HIF-1a and THBS1 expression.
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Affiliation(s)
- Xiuhua Jia
- Department of Ophthalmology, Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Yi Sun
- Department of Ophthalmology, Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Tao Wang
- Department of Ophthalmology, Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Lei Zhong
- Department of Ophthalmology, Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Juan Deng
- Department of Ophthalmology, Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China.
| | - Xiang Zhu
- Department of Infectious Diseases, Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China.
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Fu X, Feng S, Qin H, Yan L, Zheng C, Yao K. Microglia: The breakthrough to treat neovascularization and repair blood-retinal barrier in retinopathy. Front Mol Neurosci 2023; 16:1100254. [PMID: 36756614 PMCID: PMC9899825 DOI: 10.3389/fnmol.2023.1100254] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Accepted: 01/03/2023] [Indexed: 01/24/2023] Open
Abstract
Microglia are the primary resident retinal macrophages that monitor neuronal activity in real-time and facilitate angiogenesis during retinal development. In certain retinal diseases, the activated microglia promote retinal angiogenesis in hypoxia stress through neurovascular coupling and guide neovascularization to avascular areas (e.g., the outer nuclear layer and macula lutea). Furthermore, continuously activated microglia secrete inflammatory factors and expedite the loss of the blood-retinal barrier which causes irreversible damage to the secondary death of neurons. In this review, we support microglia can be a potential cellular therapeutic target in retinopathy. We briefly describe the relevance of microglia to the retinal vasculature and blood-retinal barrier. Then we discuss the signaling pathway related to how microglia move to their destinations and regulate vascular regeneration. We summarize the properties of microglia in different retinal disease models and propose that reducing the number of pro-inflammatory microglial death and conversing microglial phenotypes from pro-inflammatory to anti-inflammatory are feasible for treating retinal neovascularization and the damaged blood-retinal barrier (BRB). Finally, we suppose that the unique properties of microglia may aid in the vascularization of retinal organoids.
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Affiliation(s)
- Xuefei Fu
- Institute of Visual Neuroscience and Stem Cell Engineering, Wuhan University of Science and Technology, Wuhan, China
| | - Shuyu Feng
- Institute of Visual Neuroscience and Stem Cell Engineering, Wuhan University of Science and Technology, Wuhan, China
| | - Huan Qin
- Institute of Visual Neuroscience and Stem Cell Engineering, Wuhan University of Science and Technology, Wuhan, China
| | - Lin Yan
- Institute of Visual Neuroscience and Stem Cell Engineering, Wuhan University of Science and Technology, Wuhan, China
| | - Caiyan Zheng
- Institute of Visual Neuroscience and Stem Cell Engineering, Wuhan University of Science and Technology, Wuhan, China
| | - Kai Yao
- Institute of Visual Neuroscience and Stem Cell Engineering, Wuhan University of Science and Technology, Wuhan, China,College of Life Sciences and Health, Wuhan University of Science and Technology, Wuhan, China,Hubei Province Key Laboratory of Occupational Hazard Identification and Control, Wuhan University of Science and Technology, Wuhan, China,*Correspondence: Kai Yao,
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Henning Y, Blind US, Larafa S, Matschke J, Fandrey J. Hypoxia aggravates ferroptosis in RPE cells by promoting the Fenton reaction. Cell Death Dis 2022; 13:662. [PMID: 35906211 PMCID: PMC9338085 DOI: 10.1038/s41419-022-05121-z] [Citation(s) in RCA: 40] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Revised: 07/15/2022] [Accepted: 07/20/2022] [Indexed: 01/21/2023]
Abstract
Oxidative stress and hypoxia in the retinal pigment epithelium (RPE) have long been considered major risk factors in the pathophysiology of age-related macular degeneration (AMD), but systematic investigation of the interplay between these two risk factors was lacking. For this purpose, we treated a human RPE cell line (ARPE-19) with sodium iodate (SI), an oxidative stress agent, together with dimethyloxalylglycine (DMOG) which leads to stabilization of hypoxia-inducible factors (HIFs), key regulators of cellular adaptation to hypoxic conditions. We found that HIF stabilization aggravated oxidative stress-induced cell death by SI and iron-dependent ferroptosis was identified as the main cell death mechanism. Ferroptotic cell death depends on the Fenton reaction where H2O2 and iron react to generate hydroxyl radicals which trigger lipid peroxidation. Our findings clearly provide evidence for superoxide dismutase (SOD) driven H2O2 production fostering the Fenton reaction as indicated by triggered SOD activity upon DMOG + SI treatment as well as by reduced cell death levels upon SOD2 knockdown. In addition, iron transporters involved in non-transferrin-bound Fe2+ import as well as intracellular iron levels were also upregulated. Consequently, chelation of Fe2+ by 2'2-Bipyridyl completely rescued cells. Taken together, we show for the first time that HIF stabilization under oxidative stress conditions aggravates ferroptotic cell death in RPE cells. Thus, our study provides a novel link between hypoxia, oxidative stress and iron metabolism in AMD pathophysiology. Since iron accumulation and altered iron metabolism are characteristic features of AMD retinas and RPE cells, our cell culture model is suitable for high-throughput screening of new treatment approaches against AMD.
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Affiliation(s)
- Yoshiyuki Henning
- grid.410718.b0000 0001 0262 7331Institute of Physiology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Ursula Sarah Blind
- grid.410718.b0000 0001 0262 7331Institute of Physiology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Safa Larafa
- grid.410718.b0000 0001 0262 7331Institute of Cell Biology (Cancer Research), University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Johann Matschke
- grid.410718.b0000 0001 0262 7331Institute of Cell Biology (Cancer Research), University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Joachim Fandrey
- grid.410718.b0000 0001 0262 7331Institute of Physiology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
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10
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Tang X, Cui K, Lu X, Wu P, Yu S, Yang B, Xu Y, Liang X. A Novel Hypoxia-inducible Factor 1α Inhibitor KC7F2 Attenuates Oxygen-induced Retinal Neovascularization. Invest Ophthalmol Vis Sci 2022; 63:13. [PMID: 35695808 PMCID: PMC9202333 DOI: 10.1167/iovs.63.6.13] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose KC7F2 is a novel molecule compound that can inhibit the translation of hypoxia-inducible factor 1α (HIF1α). It has been reported to exhibit potential antiangiogenic effect. We hypothesized that KC7F2 could inhibit oxygen-induced retinal neovascularization (RNV). The purpose of this study was to investigate this assumption. Methods Oxygen-induced retinopathy (OIR) models in C57BL/6J mice and Sprague-Dawley rats were used for in vivo study. After intraperitoneal injections of KC7F2, RNV was detected by immunofluorescence and hematoxylin and eosin staining. Retinal inflammation was explored by immunofluorescence. EdU incorporation assay, cell counting kit-8 assay, scratch test, transwell assay, and Matrigel assay were used to evaluate the effect of KC7F2 on the proliferation, migration and tube formation of human umbilical vein endothelial cells (HUVEC) induced by vascular endothelial growth factor (VEGF) in vitro. Protein expression was examined by Western blot. Results KC7F2 treatment (10 mg/kg/d) in OIR mice significantly attenuated pathological neovascularization and decreased the number of preretinal neovascular cell nuclei, without changing the avascular area, which showed the same trends in OIR rats. Consistently, after the KC7F2 intervention (10 µM), cell proliferation was inhibited in VEGF-induced HUVEC, which was in agreement with the trend observed in the retinas of OIR mice. Meanwhile, KC7F2 suppressed VEGF-induced HUVEC migration and tube formation, and decreased the density of leukocytes and microglia colocalizing neovascular areas in the retinas. Moreover, the HIF1α–VEGF pathway activated in retinas of OIR mice and hypoxia-induced HUVEC, was suppressed by KC7F2 treatment. Conclusions The current study revealed that KC7F2 was able to inhibit RNV effectively via HIF1α–VEGF pathway, suggesting that it might be an effective drug for RNV treatment.
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Affiliation(s)
- Xiaoyu Tang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Kaixuan Cui
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Xi Lu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Peiqi Wu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Shanshan Yu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Boyu Yang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Yue Xu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Xiaoling Liang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
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11
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Karademir D, Todorova V, Ebner LJA, Samardzija M, Grimm C. Single-cell RNA sequencing of the retina in a model of retinitis pigmentosa reveals early responses to degeneration in rods and cones. BMC Biol 2022; 20:86. [PMID: 35413909 PMCID: PMC9006580 DOI: 10.1186/s12915-022-01280-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Accepted: 03/12/2022] [Indexed: 11/18/2022] Open
Abstract
Background In inherited retinal disorders such as retinitis pigmentosa (RP), rod photoreceptor-specific mutations cause primary rod degeneration that is followed by secondary cone death and loss of high-acuity vision. Mechanistic studies of retinal degeneration are challenging because of retinal heterogeneity. Moreover, the detection of early cone responses to rod death is especially difficult due to the paucity of cones in the retina. To resolve heterogeneity in the degenerating retina and investigate events in both types of photoreceptors during primary rod degeneration, we utilized droplet-based single-cell RNA sequencing in an RP mouse model, rd10. Results Using trajectory analysis, we defined two consecutive phases of rod degeneration at P21, characterized by the early transient upregulation of Egr1 and the later induction of Cebpd. EGR1 was the transcription factor most significantly associated with the promoters of differentially regulated genes in Egr1-positive rods in silico. Silencing Egr1 affected the expression levels of two of these genes in vitro. Degenerating rods exhibited changes associated with metabolism, neuroprotection, and modifications to synapses and microtubules. Egr1 was also the most strongly upregulated transcript in cones. Its upregulation in cones accompanied potential early respiratory dysfunction and changes in signaling pathways. The expression pattern of EGR1 in the retina was dynamic during degeneration, with a transient increase of EGR1 immunoreactivity in both rods and cones during the early stages of their degenerative processes. Conclusion Our results identify early and late changes in degenerating rd10 rod photoreceptors and reveal early responses to rod degeneration in cones not expressing the disease-causing mutation, pointing to mechanisms relevant for secondary cone degeneration. In addition, our data implicate EGR1 as a potential key regulator of early degenerative events in rods and cones, providing a potential broad target for modulating photoreceptor degeneration. Supplementary Information The online version contains supplementary material available at 10.1186/s12915-022-01280-9.
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Affiliation(s)
- Duygu Karademir
- Laboratory for Retinal Cell Biology, Department of Ophthalmology, University Hospital Zurich, University of Zurich, Zurich, Switzerland. .,Zurich Center for Integrative Human Physiology, University of Zurich, Zurich, Switzerland.
| | - Vyara Todorova
- Laboratory for Retinal Cell Biology, Department of Ophthalmology, University Hospital Zurich, University of Zurich, Zurich, Switzerland.,Neuroscience Center Zurich, University of Zurich, Zurich, Switzerland
| | - Lynn J A Ebner
- Laboratory for Retinal Cell Biology, Department of Ophthalmology, University Hospital Zurich, University of Zurich, Zurich, Switzerland.,Zurich Center for Integrative Human Physiology, University of Zurich, Zurich, Switzerland
| | - Marijana Samardzija
- Laboratory for Retinal Cell Biology, Department of Ophthalmology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Christian Grimm
- Laboratory for Retinal Cell Biology, Department of Ophthalmology, University Hospital Zurich, University of Zurich, Zurich, Switzerland.,Zurich Center for Integrative Human Physiology, University of Zurich, Zurich, Switzerland.,Neuroscience Center Zurich, University of Zurich, Zurich, Switzerland
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12
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Kim Y, Kim DY, Zhang H, Bae CR, Seong D, Kim Y, Song J, Kim YM, Kwon YG. DIX domain containing 1 (DIXDC1) modulates VEGFR2 level in vasculatures to regulate embryonic and postnatal retina angiogenesis. BMC Biol 2022; 20:41. [PMID: 35144597 PMCID: PMC8830128 DOI: 10.1186/s12915-022-01240-3] [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: 06/23/2021] [Accepted: 01/27/2022] [Indexed: 11/16/2022] Open
Abstract
Background In sprouting angiogenesis, VEGFR2 level is regulated via a fine-tuned process involving various signaling pathways. Other than VEGF/VEGFR2 signaling pathway, Wnt/ β-catenin signaling is also important in vascular development. However, the crosstalk between these two signaling pathways is still unknown to date. In this study, we aimed to investigate the role of DIX domain containing 1 (DIXDC1) in vasculature, facilitating the crosstalk between VEGF/VEGFR2 and Wnt/ β-catenin signaling pathways. Results In mice, DIXDC1 deficiency delayed angiogenesis at the embryonic stage and suppressed neovascularization at the neonatal stage. DIXDC1 knockdown inhibited VEGF-induced angiogenesis in endothelial cells in vitro by downregulating VEGFR2 expression. DIXDC1 bound Dishevelled Segment Polarity Protein 2 (Dvl2) and polymerized Dvl2 stabilizing VEGFR2 protein via its direct interaction. The complex formation and stability of VEGFR2 was potentiated by Wnt signaling. Moreover, hypoxia elevated DIXDC1 expression and likely modulated both canonical Wnt/β-catenin signaling and VEGFR2 stability in vasculatures. Pathological angiogenesis in DIXDC1 knockout mice was decreased significantly in oxygen-induced retinopathy (OIR) and in wound healing models. These results suggest that DIXDC1 is an important factor in developmental and pathological angiogenesis. Conclusion We have identified DIXDC1 as an important factor in early vascular development. These results suggest that DIXDC1 represents a novel regulator of sprouting angiogenesis that links Wnt signaling and VEGFR2 stability and may have a potential role in pathological neovascularization. Supplementary Information The online version contains supplementary material available at 10.1186/s12915-022-01240-3.
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Affiliation(s)
- Yeaji Kim
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul, Republic of Korea
| | - Dong Young Kim
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul, Republic of Korea.,Present address: Division of Radiation Biomedical Research, Korea Institute of Radiological and Medical Sciences, Seoul, Republic of Korea
| | - Haiying Zhang
- R&D Department, Curacle Co. Ltd, Seongnam-si, Republic of Korea
| | - Cho-Rong Bae
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul, Republic of Korea
| | - Daehyeon Seong
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul, Republic of Korea
| | - Yeomyung Kim
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul, Republic of Korea
| | - Jaewhan Song
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul, Republic of Korea
| | - Young-Myeong Kim
- Vascular System Research Center, Kangwon National University, Chuncheon, Republic of Korea
| | - Young-Guen Kwon
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul, Republic of Korea.
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13
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Qiang W, Wei R, Chen Y, Chen D. Clinical Pathological Features and Current Animal Models of Type 3 Macular Neovascularization. Front Neurosci 2021; 15:734860. [PMID: 34512255 PMCID: PMC8427186 DOI: 10.3389/fnins.2021.734860] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Accepted: 07/29/2021] [Indexed: 02/05/2023] Open
Abstract
Type 3 macular neovascularization (MNV3), or retinal angiomatous proliferation (RAP), is a distinct type of neovascular age-related macular degeneration (AMD), which is a leading cause of vision loss in older persons. During the past decade, systematic investigation into the clinical, multimodal imaging, and histopathological features and therapeutic outcomes has provided important new insight into this disease. These studies favor the retinal origin of MNV3 and suggest the involvement of retinal hypoxia, inflammation, von Hippel–Lindau (VHL)–hypoxia-inducible factor (HIF)–vascular endothelial growth factor (VEGF) pathway, and multiple cell types in the development and progression of MNV3. Several mouse models, including the recently built Rb/p107/Vhl triple knockout mouse model by our group, have induced many of the histological features of MNV3 and provided much insight into the underlying pathological mechanisms. These models have revealed the roles of retinal hypoxia, inflammation, lipid metabolism, VHL/HIF pathway, and retinoblastoma tumor suppressor (Rb)–E2F cell cycle pathway in the development of MNV3. This article will summarize the clinical, multimodal imaging, and pathological features of MNV3 and the diversity of animal models that exist for MNV3, as well as their strengths and limitations.
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Affiliation(s)
- Wei Qiang
- Research Laboratory of Ophthalmology and Vision Sciences, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China.,Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, China
| | - Ran Wei
- Research Laboratory of Ophthalmology and Vision Sciences, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China.,Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, China
| | - Yongjiang Chen
- The School of Optometry and Vision Science, University of Waterloo, Waterloo, ON, Canada
| | - Danian Chen
- Research Laboratory of Ophthalmology and Vision Sciences, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China.,Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, China
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14
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Qiu Q, Lv P, Zhongshen Y, Yuan F, Zhang X, Zhou X, Li S, Liu X, Zhang J. Electrophysiological mechanisms underlying hypoxia-induced deficits in visual spatial and non-spatial discrimination. Physiol Rep 2021; 9:e15036. [PMID: 34558212 PMCID: PMC8461214 DOI: 10.14814/phy2.15036] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2021] [Revised: 08/19/2021] [Accepted: 08/23/2021] [Indexed: 12/16/2022] Open
Abstract
Impaired visual cognition in residents of hypoxic environment has been widely reported; however, the underlying electrophysiological mechanisms remain unclear. In this study, 23 college students underwent three sessions of a Clock task test before a 30-day high-altitude exposure (Test 1) and 1 week (Test 2) and 3 months (Test 3) after they returned to lowlands. The Clock task consists of a visual spatial angle and a visual non-spatial color discrimination subtask. Simultaneously, electroencephalography (EEG) was recorded during the Clock task. The behavioral results showed that, compared with Test 1, accuracy in Test 2 was significantly decreased in both the Angle and Color tasks, and reaction time (RT) was significantly increased in the Angle task. The event-related potentials results showed that, during both tasks amplitudes of the occipital N1 and P3 components during both tasks were significantly decreased in Test 2, compared with Test 1. Moreover, N1 amplitude was negatively correlated with RT and positively correlated with accuracy. Further time-frequency EEG analysis showed that theta power at occipital sites was significantly decreased in both tasks in Test 2, compared with Test 1, and was negatively correlated with RT in the Angle task. In Test 3, both the behavioral performance and EEG activity recovered to the baseline level in Test 1. These findings suggested that hypoxia impairs both visual spatial and visual non-spatial discriminations, and these impairments can recover after subjects return to lowlands. Inhibition of brain electrophysiological activity in the visual cortex may explain the deficits in visual cognition.
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Affiliation(s)
- Qi Qiu
- Institute of Brain Diseases and CognitionSchool of MedicineXiamen UniversityXiamenFujianChina
| | - Pengpeng Lv
- Department of Clinical MedicineSchool of MedicineXiamen UniversityXiamenFujianChina
| | - Yihao Zhongshen
- Department of Traditional Chinese MedicineSchool of MedicineXiamen UniversityXiamenFujianChina
| | - Fengjuan Yuan
- Institute of Brain Diseases and CognitionSchool of MedicineXiamen UniversityXiamenFujianChina
| | - Xinjuan Zhang
- Institute of Brain Diseases and CognitionSchool of MedicineXiamen UniversityXiamenFujianChina
| | - Xiuzhu Zhou
- Department of Gynecology and ObstetricsThe First Affiliated Hospital of Xiamen UniversityXiamenFujianChina
| | - Shanhua Li
- Institute of Brain Diseases and CognitionSchool of MedicineXiamen UniversityXiamenFujianChina
| | - Xiaonan Liu
- Institute of PsychologySchool of Public PolicyXiamen UniversityXiamenFujianChina
| | - Jiaxing Zhang
- Institute of Brain Diseases and CognitionSchool of MedicineXiamen UniversityXiamenFujianChina
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15
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Transcriptomic analysis of the mouse retina after acute and chronic normobaric and hypobaric hypoxia. Sci Rep 2021; 11:16666. [PMID: 34404875 PMCID: PMC8371159 DOI: 10.1038/s41598-021-96150-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Accepted: 08/05/2021] [Indexed: 12/13/2022] Open
Abstract
Oxygen delivery to the retinal pigment epithelium and the outer retina is essential for metabolism, function, and survival of photoreceptors. Chronically reduced oxygen supply leads to retinal pathologies in patients and causes age-dependent retinal degeneration in mice. Hypoxia can result from decreased levels of inspired oxygen (normobaric hypoxia) or reduced barometric pressure (hypobaric hypoxia). Since the response of retinal cells to chronic normobaric or hypobaric hypoxia is mostly unknown, we examined the effect of six hypoxic conditions on the retinal transcriptome and photoreceptor morphology. Mice were exposed to short- and long-term normobaric hypoxia at 400 m or hypobaric hypoxia at 3450 m above sea level. Longitudinal studies over 11 weeks in normobaric hypoxia revealed four classes of genes that adapted differentially to the hypoxic condition. Seventeen genes were specifically regulated in hypobaric hypoxia and may affect the structural integrity of the retina, resulting in the shortening of photoreceptor segment length detected in various hypoxic groups. This study shows that retinal cells have the capacity to adapt to long-term hypoxia and that consequences of hypobaric hypoxia differ from those of normobaric hypoxia. Our datasets can be used as references to validate and compare retinal disease models associated with hypoxia.
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16
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Heisel C, Yousif J, Mijiti M, Charizanis K, Brigell M, Corson TW, Kelley MR. APE1/Ref-1 as a Novel Target for Retinal Diseases. JOURNAL OF CELLULAR SIGNALING 2021; 2:133-138. [PMID: 34322687 PMCID: PMC8315574 DOI: 10.33696/signaling.2.044] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
APE1/Ref-1 (also called Ref-1) has been extensively studied for its role in DNA repair and reduction-oxidation (redox) signaling. The review titled: “The multifunctional APE1 DNA repair-redox signaling protein as a drug target in human disease” by Caston et. al. summarizes the molecular functions of Ref-1 and the role it plays in a number of diseases, with a specific focus on various types of cancer [1]. Previous studies have demonstrated that Ref-1 plays a critical role in regulating specific transcription factors (TFs) involved in a number of pathways, not only in cancer, but other disease indications as well. Disease indications of particular therapeutic interest include retinal vascular diseases such as diabetic retinopathy (DR), diabetic macular edema (DME), and neovascular age-related macular degeneration (nvAMD). While Ref-1 controls a number of TFs that are under redox regulation, three have been found to directly link cancer studies to retinal diseases; HIF-1α, NF-κB and STAT3. HIF-1α controls the expression of VEGF for angiogenesis while NF-κB and STAT3 regulate a number of known cytokines and factors involved in inflammation. These pathways are highly implicated and validated as major players in DR, DME and AMD. Therefore, findings in cancer studies for Ref-1 and its inhibition may be translated to these ocular diseases. This report discusses the path from cancer to the potential treatment of retinal disease, the Ref-1 redox signaling function as a possible target, and the current small molecules which have been identified to block this activity. One molecule, APX3330, is in clinical trials, while the others are in preclinical development. Inhibition of Ref-1 and its effects on inflammation and angiogenesis makes it a potential new therapeutic target for the treatment of retinal vascular diseases. This commentary summarizes the retinal-relevant research that built on the results summarized in the review by Caston et. al. [1].
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Affiliation(s)
- Curtis Heisel
- University of Michigan Medical School, 1301 Catherine St, Ann Arbor, MI 48105, USA
| | - Jonah Yousif
- University of Michigan Medical School, 1301 Catherine St, Ann Arbor, MI 48105, USA
| | - Mahmut Mijiti
- Herman B Wells Center for Pediatric Research, Department of Pediatrics, Indiana University School of Medicine, 1044 W. Walnut St., Indianapolis, IN 46202, USA
| | | | | | - Timothy W Corson
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, 1044 W. Walnut St., Indianapolis, IN 46202, USA.,Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, 1044 W. Walnut St., Indianapolis, IN 46202, USA.,Indiana University Simon Comprehensive Cancer Center, Indiana University School of Medicine, 1044 W. Walnut St., Indianapolis, IN 46202, USA.,Eugene and Marilyn Glick Eye Institute, Department of Ophthalmology, Indiana University School of Medicine, 1044 W. Walnut St., Indianapolis, IN 46202, USA
| | - Mark R Kelley
- Herman B Wells Center for Pediatric Research, Department of Pediatrics, Indiana University School of Medicine, 1044 W. Walnut St., Indianapolis, IN 46202, USA.,Department of Pharmacology and Toxicology, Indiana University School of Medicine, 1044 W. Walnut St., Indianapolis, IN 46202, USA.,Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, 1044 W. Walnut St., Indianapolis, IN 46202, USA.,Indiana University Simon Comprehensive Cancer Center, Indiana University School of Medicine, 1044 W. Walnut St., Indianapolis, IN 46202, USA.,Eugene and Marilyn Glick Eye Institute, Department of Ophthalmology, Indiana University School of Medicine, 1044 W. Walnut St., Indianapolis, IN 46202, USA
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17
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Sundaramurthi H, Roche SL, Grice GL, Moran A, Dillion ET, Campiani G, Nathan JA, Kennedy BN. Selective Histone Deacetylase 6 Inhibitors Restore Cone Photoreceptor Vision or Outer Segment Morphology in Zebrafish and Mouse Models of Retinal Blindness. Front Cell Dev Biol 2020; 8:689. [PMID: 32984302 PMCID: PMC7479070 DOI: 10.3389/fcell.2020.00689] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Accepted: 07/07/2020] [Indexed: 12/19/2022] Open
Abstract
Blindness arising from retinal or macular degeneration results in significant social, health and economic burden. While approved treatments exist for neovascular (‘wet’) age-related macular degeneration, new therapeutic targets/interventions are needed for the more prevalent atrophic (‘dry’) form of age-related macular degeneration. Similarly, in inherited retinal diseases, most patients have no access to an effective treatment. Although macular and retinal degenerations are genetically and clinically distinct, common pathological hallmarks can include photoreceptor degeneration, retinal pigment epithelium atrophy, oxidative stress, hypoxia and defective autophagy. Here, we evaluated the potential of selective histone deacetylase 6 inhibitors to preserve retinal morphology or restore vision in zebrafish atp6v0e1–/– and mouse rd10 models. Histone deacetylase 6 inhibitor, tubastatin A-treated atp6v0e1–/– zebrafish show marked improvement in photoreceptor outer segment area (44.7%, p = 0.027) and significant improvement in vision (8-fold, p ≤ 0.0001). Tubastatin A-treated rd10/rd10 retinal explants show a significantly (p = 0.016) increased number of outer-segment labeled cone photoreceptors. In vitro, ATP6V0E1 regulated HIF-1α activity, but significant regulation of HIF-1α by histone deacetylase 6 inhibition in the retina was not detected. Proteomic profiling identified ubiquitin-proteasome, phototransduction, metabolism and phagosome as pathways, whose altered expression correlated with histone deacetylase 6 inhibitor mediated restoration of vision.
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Affiliation(s)
- Husvinee Sundaramurthi
- UCD Conway Institute, University College Dublin, Dublin, Ireland.,UCD School of Biomolecular and Biomedical Science, University College Dublin, Dublin, Ireland.,Systems Biology Ireland, University College Dublin, Dublin, Ireland.,UCD School of Medicine, University College Dublin, Dublin, Ireland
| | - Sarah L Roche
- School of Biochemistry, University College Cork, Cork, Ireland
| | - Guinevere L Grice
- Cambridge Institute of Therapeutic Immunology & Infectious Disease, University of Cambridge, Cambridge, United Kingdom
| | - Ailis Moran
- UCD Conway Institute, University College Dublin, Dublin, Ireland.,UCD School of Biomolecular and Biomedical Science, University College Dublin, Dublin, Ireland
| | - Eugene T Dillion
- UCD School of Biomolecular and Biomedical Science, University College Dublin, Dublin, Ireland.,Mass Spectrometry Resource, UCD Conway Institute, University College Dublin, Dublin, Ireland
| | - Giuseppe Campiani
- Department of Biotechnology, Chemistry and Pharmacy, Department of Excellence, University of Siena, Siena, Italy
| | - James A Nathan
- Cambridge Institute of Therapeutic Immunology & Infectious Disease, University of Cambridge, Cambridge, United Kingdom
| | - Breandán N Kennedy
- UCD Conway Institute, University College Dublin, Dublin, Ireland.,UCD School of Biomolecular and Biomedical Science, University College Dublin, Dublin, Ireland
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18
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Zhang X, Sun Y, Song D, Diao Y. κ-opioid receptor agonists may alleviate intestinal damage in cardiopulmonary bypass rats by inhibiting the NF-κB/HIF-1α pathway. Exp Ther Med 2020; 20:325-334. [PMID: 32509012 PMCID: PMC7271736 DOI: 10.3892/etm.2020.8685] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Accepted: 03/05/2020] [Indexed: 02/07/2023] Open
Abstract
The aims of the present study were to investigate the protective effect of a κ-opioid receptor (KOR) agonist on intestinal barrier dysfunction in rats during cardiopulmonary bypass (CPB), as well as to examine the role of NF-κB and the transcription factor hypoxia-inducible factor-1α (HIF-1α) signaling pathway in the regulatory mechanism. A total of 50 rats were randomly divided into five groups, with 10 rats in each group: Sham surgery group (group Sham), CPB surgery group (group CPB), KOR agonist + CPB (group K), KOR agonist + specific KOR antagonist + CBP (group NK) and KOR agonist + NF-κB pathway specific inhibitor + CPB (group NF). Intestinal microcirculation was evaluated to determine intestinal barrier dysfunction in rats following CPB surgery. Hematoxylin and eosin (H&E) staining was used to observe intestinal tissue injury in the rats. ELISA was used to detect the inflammatory factors interleukin (IL)-1β, IL-6, IL10 and tumor necrosis factor-α, and the oxidative stress factors superoxidase dismutase, malondialdehyde and nitric oxide in serum. In addition, ELISA was used to investigate the serum levels of the intestinal damage markers D-lactic acid, diamine oxidase and intestinal fatty acid-binding protein. Western blotting was used to investigate the protein expression levels of tight junction proteins zonula occludens-1 and claudin-1. Furthermore, immunohistochemistry was used to examine intestinal injuries and western blotting was used to detect expression levels of NF-κB/HIF-1α signaling pathway-related proteins. H&E staining results suggested that the KOR agonist alleviated intestinal damage in the CPB model rats. This effect was reversed by the addition of a KOR antagonist. Further investigation of inflammatory and oxidative stress factors using ELISA revealed that the KOR agonist reduced the inflammatory and oxidative stress responses in the intestinal tissues of the CPB model rats. The ELISA results of intestinal damage markers and western blotting results of tight junction protein expression suggested that KOR agonist treatment may alleviate intestinal injury in CPB model rats. In addition, the western blotting and immunohistochemistry results suggested that KOR agonists may decrease the expression levels of NF-κB, p65 and HIF-1α in CPB. Collectively, the present results suggested that KOR agonists are able to ameliorate the intestinal barrier dysfunction in rats undergoing CPB by inhibiting the expression levels of NF-κB/HIF-1α signaling pathway-related proteins.
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Affiliation(s)
- Xiaoyan Zhang
- Postgraduate Training Base of The General Hospital of Northern Theater Command, Jinzhou Medical University, Jinzhou, Liaoning 121013, P.R. China.,Department of Anesthesia, The General Hospital of Northern Theater Command, Shenyang, Liaoning 110016, P.R. China
| | - Yingjie Sun
- Department of Anesthesia, The General Hospital of Northern Theater Command, Shenyang, Liaoning 110016, P.R. China
| | - Dandan Song
- Department of Anesthesia, The General Hospital of Northern Theater Command, Shenyang, Liaoning 110016, P.R. China
| | - Yugang Diao
- Department of Anesthesia, The General Hospital of Northern Theater Command, Shenyang, Liaoning 110016, P.R. China
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19
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The Expression of Decidual Protein Induced by Progesterone (DEPP) is Controlled by Three Distal Consensus Hypoxia Responsive Element (HRE) in Hypoxic Retinal Epithelial Cells. Genes (Basel) 2020; 11:genes11010111. [PMID: 31963726 PMCID: PMC7016973 DOI: 10.3390/genes11010111] [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: 11/19/2019] [Revised: 01/10/2020] [Accepted: 01/14/2020] [Indexed: 11/16/2022] Open
Abstract
Hypoxia affects the development and/or progression of several retinopathies. Decidual protein induced by progesterone (DEPP) has been identified as a hypoxia-responsive gene that may be part of cellular pathways such as autophagy and connected to retinal diseases. To increase our understanding of DEPP regulation in the eye, we defined its expression pattern in mouse and human retina and retinal pigment epithelium (RPE). Interestingly, DEPP expression was increased in an age-dependent way in the central human RPE. We showed that DEPP was regulated by hypoxia in the mouse retina and eyecup and that this regulation was controlled by hypoxia-inducible transcription factors 1 and 2 (HIF1 and HIF2). Furthermore, we identified three hypoxia response elements (HREs) about 3.5 kb proximal to the transcriptional start site that were responsible for hypoxic induction of DEPP in a human RPE cell line. Comparative genomics analysis suggested that one of the three HREs resides in a highly conserved genomic region. Collectively, we defined the molecular elements controlling hypoxic induction of DEPP in an RPE cell line, and provided evidence for an enrichment of DEPP in the aged RPE of human donors. This makes DEPP an interesting gene to study with respect to aging and age-related retinal pathologies.
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20
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Wei R, Ren X, Kong H, Lv Z, Chen Y, Tang Y, Wang Y, Xiao L, Yu T, Hacibekiroglu S, Liang C, Nagy A, Bremner R, Chen D. Rb1/Rbl1/Vhl loss induces mouse subretinal angiomatous proliferation and hemangioblastoma. JCI Insight 2019; 4:127889. [PMID: 31613797 DOI: 10.1172/jci.insight.127889] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Accepted: 10/10/2019] [Indexed: 02/05/2023] Open
Abstract
Von Hippel-Lindau (Vhl) protein inhibits hypoxia-inducible factor (Hif), yet its deletion in murine retina does not cause the extensive angiogenesis expected with Hif induction. The mechanism is unclear. Here we show that retinoblastoma tumor suppressor (Rb1) constrains expression of Hif target genes in the Vhl-/- retina. Deleting Rb1 induced extensive retinal neovascularization and autophagic ablation of photoreceptors in the Vhl-/- retina. RNA-sequencing, ChIP, and reporter assays showed Rb1 recruitment to and repression of certain Hif target genes. Activating Rb1 by deleting cyclin D1 induced a partial defect in the retinal superficial vascular plexus. Unexpectedly, removing Vhl suppressed retinoblastoma formation in murine Rb1/Rbl1-deficient retina but generated subretinal vascular growths resembling retinal angiomatous proliferation (RAP) and retinal capillary hemangioblastoma (RCH). Most stromal cells in the RAP/RCH-like lesions were Sox9+, suggesting a Müller glia origin, and expressed Lgals3, a marker of human brain hemangioblastoma. Thus, the Rb family limit Hif target gene expression in the Vhl-/- retina, and removing this inhibitory signal generates new models for RAP and RCH.
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Affiliation(s)
- Ran Wei
- Research Laboratory of Ophthalmology and Vision Sciences, State Key Laboratory of Biotherapy, and.,Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, China
| | - Xiang Ren
- Research Laboratory of Ophthalmology and Vision Sciences, State Key Laboratory of Biotherapy, and.,Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, China
| | - Hongyu Kong
- Research Laboratory of Ophthalmology and Vision Sciences, State Key Laboratory of Biotherapy, and.,Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, China
| | - Zhongping Lv
- Research Laboratory of Ophthalmology and Vision Sciences, State Key Laboratory of Biotherapy, and.,Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, China
| | - Yongjiang Chen
- Lunenfeld-Tanenbaum Research Institute, Sinai Health System, and Departments of Ophthalmology and Visual Science, and Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada.,Lunenfeld-Tanenbaum Research Institute, Sinai Health System, and Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada
| | - Yunjing Tang
- Research Laboratory of Ophthalmology and Vision Sciences, State Key Laboratory of Biotherapy, and.,Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, China
| | - Yujiao Wang
- Research Laboratory of Ophthalmology and Vision Sciences, State Key Laboratory of Biotherapy, and.,Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, China
| | - Lirong Xiao
- Research Laboratory of Ophthalmology and Vision Sciences, State Key Laboratory of Biotherapy, and
| | - Tao Yu
- Lunenfeld-Tanenbaum Research Institute, Sinai Health System, and Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada
| | - Sabiha Hacibekiroglu
- Lunenfeld-Tanenbaum Research Institute, Sinai Health System, and Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada
| | - Chen Liang
- Research Laboratory of Ophthalmology and Vision Sciences, State Key Laboratory of Biotherapy, and
| | - Andras Nagy
- Lunenfeld-Tanenbaum Research Institute, Sinai Health System, and Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada
| | - Rod Bremner
- Lunenfeld-Tanenbaum Research Institute, Sinai Health System, and Departments of Ophthalmology and Visual Science, and Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada.,Lunenfeld-Tanenbaum Research Institute, Sinai Health System, and Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada
| | - Danian Chen
- Research Laboratory of Ophthalmology and Vision Sciences, State Key Laboratory of Biotherapy, and.,Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, China.,Lunenfeld-Tanenbaum Research Institute, Sinai Health System, and Departments of Ophthalmology and Visual Science, and Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada.,Lunenfeld-Tanenbaum Research Institute, Sinai Health System, and Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada
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21
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Hif1a and Hif2a can be safely inactivated in cone photoreceptors. Sci Rep 2019; 9:16121. [PMID: 31695081 PMCID: PMC6834587 DOI: 10.1038/s41598-019-52508-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Accepted: 10/14/2019] [Indexed: 12/30/2022] Open
Abstract
Impaired tissue oxygenation results in hypoxia and leads to the activation of hypoxia-inducible transcription factors (HIF). A chronic, HIF-triggered molecular response to hypoxia may be an important factor in the etiology of age-related macular degeneration (AMD) and is likely activated before any clinical manifestation of the disease. Thus, HIF1 and HIF2 recently emerged as potential therapeutic targets for AMD. To address and evaluate potential consequences of anti-HIF therapies for retinal physiology and function, we generated mouse lines that have Hif1a, or both Hif1a and Hif2a ablated specifically in cone photoreceptors. The knockdown of Hifs in cones did not cause detectable pathological alterations such as loss of cone photoreceptors, retinal degeneration or abnormalities of the retinal vasculature, had no impact on retinal function and resulted in a similar tolerance to hypoxic exposure. Our data indicate that HIF transcription factors are dispensable for maintaining normal cone function and survival in retinas of adult mice. This study provides the groundwork necessary to establish safety profiles for strategies aiming at antagonizing HIF1A and HIF2A function in cone photoreceptors for the treatment of retinal degenerative diseases that involve a hypoxic component such as AMD.
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22
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Light stress affects cones and horizontal cells via rhodopsin-mediated mechanisms. Exp Eye Res 2019; 186:107719. [PMID: 31291592 DOI: 10.1016/j.exer.2019.107719] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Revised: 07/04/2019] [Accepted: 07/04/2019] [Indexed: 01/20/2023]
Abstract
Retinal degenerations are a major cause of blindness in human patients. The identification of endogenous mechanisms involved in neurodegeneration or neuroprotection helps to understand the response of the retina to stress and provides essential information not only for basic retinal physiology but also for defining molecular targets for neuroprotective strategies. Here we used excessive light exposure as a model system to study mechanisms of photoreceptor degeneration in mice. Using one wild type and four genetically modified mouse strains, we demonstrate that light exposure resulted not only in the degeneration of rods but also in an early but transient repression of several cone-specific genes, in a reversible hyperreflectivity of the outer retina including the outer plexiform layer, and in the loss of horizontal cells. The effects on cones, horizontal cells and the inner retina depended on light absorption by rhodopsin and, at least partially, on leukemia inhibitory factor. This demonstrates the existence of intercellular communication routes that transduce rod stress to other cells, likely to provide support for photoreceptors and increase cell survival in the injured retina.
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23
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Schori C, Trachsel C, Grossmann J, Barben M, Klee K, Storti F, Samardzija M, Grimm C. A chronic hypoxic response in photoreceptors alters the vitreous proteome in mice. Exp Eye Res 2019; 185:107690. [PMID: 31181196 DOI: 10.1016/j.exer.2019.107690] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2019] [Revised: 05/20/2019] [Accepted: 06/06/2019] [Indexed: 02/08/2023]
Abstract
Reduced oxygenation of the outer retina in the aging eye may activate a chronic hypoxic response in RPE and photoreceptor cells and is considered as a risk factor for the development of age-related macular degeneration (AMD). In mice, a chronically active hypoxic response in the retinal pigment epithelium (RPE) or photoreceptors leads to age-dependent retinal degeneration. To identify proteins that may serve as accessible markers for a chronic hypoxic insult to photoreceptors, we used proteomics to determine the protein composition of the vitreous humor in genetically engineered mice that lack the von Hippel-Lindau tumor suppressor (Vhl) specifically in rods (rodΔVhl) or cones (all-coneΔVhl). Absence of VHL leads to constitutively active hypoxia-inducible transcription factors (HIFs) and thus to a molecular response to hypoxia even in normal room air. To discriminate between the consequences of a local response in photoreceptors and systemic hypoxic effects, we also evaluated the vitreous proteome of wild type mice after exposure to acute hypoxia. 1'043 of the identified proteins were common to all three hypoxia models. 257, 258 and 356 proteins were significantly regulated after systemic hypoxia, in rodΔVhl and in all-coneΔVhl mice, respectively, at least at one of the analyzed time points. Only few of the regulated proteins were shared by the models indicating that the vitreous proteome is differentially affected by systemic hypoxia and the rod or cone-specific hypoxic response. Similarly, the distinct protein compositions in the individual genetic models at early and late time points suggest regulated, cell-specific and time-dependent processes. Among the proteins commonly regulated in the genetic models, guanylate binding protein 2 (GBP2) showed elevated levels in the vitreous that were accompanied by increased mRNA expression in the retina of both rodΔVhl and all-coneΔVhl mice. We hypothesize that some of the differentially regulated proteins at early time points may potentially be used as markers for the detection of a chronic hypoxic response of photoreceptors.
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Affiliation(s)
- Christian Schori
- Lab for Retinal Cell Biology, Dept. Ophthalmology, University of Zurich, Zurich, Switzerland; Center for Integrative Human Physiology (ZIHP), University of Zurich, Zurich, Switzerland
| | - Christian Trachsel
- Functional Genomics Center Zurich (FGCZ), ETH Zurich and University of Zurich, Zurich, Switzerland
| | - Jonas Grossmann
- Functional Genomics Center Zurich (FGCZ), ETH Zurich and University of Zurich, Zurich, Switzerland
| | - Maya Barben
- Lab for Retinal Cell Biology, Dept. Ophthalmology, University of Zurich, Zurich, Switzerland; Neuroscience Center Zurich (ZNZ), University of Zurich, Zurich, Switzerland
| | - Katrin Klee
- Lab for Retinal Cell Biology, Dept. Ophthalmology, University of Zurich, Zurich, Switzerland; Center for Integrative Human Physiology (ZIHP), University of Zurich, Zurich, Switzerland
| | - Federica Storti
- Lab for Retinal Cell Biology, Dept. Ophthalmology, University of Zurich, Zurich, Switzerland
| | - Marijana Samardzija
- Lab for Retinal Cell Biology, Dept. Ophthalmology, University of Zurich, Zurich, Switzerland
| | - Christian Grimm
- Lab for Retinal Cell Biology, Dept. Ophthalmology, University of Zurich, Zurich, Switzerland; Center for Integrative Human Physiology (ZIHP), University of Zurich, Zurich, Switzerland; Neuroscience Center Zurich (ZNZ), University of Zurich, Zurich, Switzerland.
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24
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Storti F, Klee K, Todorova V, Steiner R, Othman A, van der Velde-Visser S, Samardzija M, Meneau I, Barben M, Karademir D, Pauzuolyte V, Boye SL, Blaser F, Ullmer C, Dunaief JL, Hornemann T, Rohrer L, den Hollander A, von Eckardstein A, Fingerle J, Maugeais C, Grimm C. Impaired ABCA1/ABCG1-mediated lipid efflux in the mouse retinal pigment epithelium (RPE) leads to retinal degeneration. eLife 2019; 8:45100. [PMID: 30864945 PMCID: PMC6435327 DOI: 10.7554/elife.45100] [Citation(s) in RCA: 58] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Accepted: 03/12/2019] [Indexed: 01/04/2023] Open
Abstract
Age-related macular degeneration (AMD) is a progressive disease of the retinal pigment epithelium (RPE) and the retina leading to loss of central vision. Polymorphisms in genes involved in lipid metabolism, including the ATP-binding cassette transporter A1 (ABCA1), have been associated with AMD risk. However, the significance of retinal lipid handling for AMD pathogenesis remains elusive. Here, we study the contribution of lipid efflux in the RPE by generating a mouse model lacking ABCA1 and its partner ABCG1 specifically in this layer. Mutant mice show lipid accumulation in the RPE, reduced RPE and retinal function, retinal inflammation and RPE/photoreceptor degeneration. Data from human cell lines indicate that the ABCA1 AMD risk-conferring allele decreases ABCA1 expression, identifying the potential molecular cause that underlies the genetic risk for AMD. Our results highlight the essential homeostatic role for lipid efflux in the RPE and suggest a pathogenic contribution of reduced ABCA1 function to AMD.
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Affiliation(s)
- Federica Storti
- Lab for Retinal Cell Biology, Department of Ophthalmology, University of Zurich, Schlieren, Switzerland
| | - Katrin Klee
- Lab for Retinal Cell Biology, Department of Ophthalmology, University of Zurich, Schlieren, Switzerland.,Center for Integrative Human Physiology, University of Zurich, Zurich, Switzerland
| | - Vyara Todorova
- Lab for Retinal Cell Biology, Department of Ophthalmology, University of Zurich, Schlieren, Switzerland.,Neuroscience Center Zurich, University of Zurich, Zurich, Switzerland
| | - Regula Steiner
- Institute of Clinical Chemistry, University of Zurich, Schlieren, Switzerland
| | - Alaa Othman
- Institute of Clinical Chemistry, University of Zurich, Schlieren, Switzerland
| | | | - Marijana Samardzija
- Lab for Retinal Cell Biology, Department of Ophthalmology, University of Zurich, Schlieren, Switzerland
| | - Isabelle Meneau
- Department of Ophthalmology, University Hospital Zurich, Zurich, Switzerland
| | - Maya Barben
- Lab for Retinal Cell Biology, Department of Ophthalmology, University of Zurich, Schlieren, Switzerland
| | - Duygu Karademir
- Lab for Retinal Cell Biology, Department of Ophthalmology, University of Zurich, Schlieren, Switzerland.,Center for Integrative Human Physiology, University of Zurich, Zurich, Switzerland
| | - Valda Pauzuolyte
- Lab for Retinal Cell Biology, Department of Ophthalmology, University of Zurich, Schlieren, Switzerland
| | - Sanford L Boye
- Department of Ophthalmology, University of Florida, Gainesville, United States
| | - Frank Blaser
- Department of Ophthalmology, University Hospital Zurich, Zurich, Switzerland
| | - Christoph Ullmer
- Roche Pharma Research and Early Development, Roche Innovation Center Basel, F Hoffmann-La Roche Ltd., Basel, Switzerland
| | - Joshua L Dunaief
- Department of Ophthalmology, Scheie Eye Institute, University of Pennsylvania, Philadelphia, United States
| | - Thorsten Hornemann
- Institute of Clinical Chemistry, University of Zurich, Schlieren, Switzerland
| | - Lucia Rohrer
- Institute of Clinical Chemistry, University of Zurich, Schlieren, Switzerland
| | - Anneke den Hollander
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, Netherlands.,Department of Ophthalmology, Radboud University Medical Center, Nijmegen, Netherlands
| | | | - Jürgen Fingerle
- Natural and Medical Sciences Institute, University of Tübingen, Tübingen, Germany
| | - Cyrille Maugeais
- Roche Pharma Research and Early Development, Roche Innovation Center Basel, F Hoffmann-La Roche Ltd., Basel, Switzerland
| | - Christian Grimm
- Lab for Retinal Cell Biology, Department of Ophthalmology, University of Zurich, Schlieren, Switzerland.,Center for Integrative Human Physiology, University of Zurich, Zurich, Switzerland.,Neuroscience Center Zurich, University of Zurich, Zurich, Switzerland
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25
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Henning Y, Osadnik C, Malkemper EP. EyeCi: Optical clearing and imaging of immunolabeled mouse eyes using light-sheet fluorescence microscopy. Exp Eye Res 2018; 180:137-145. [PMID: 30578790 DOI: 10.1016/j.exer.2018.12.001] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2018] [Revised: 11/03/2018] [Accepted: 12/05/2018] [Indexed: 01/24/2023]
Abstract
Immunofluorescent imaging is an indispensable technique to study morphology and molecular aspects in tissues. Classical approaches make it necessary to cut physical sections of tissue samples to overcome the limited penetration depth of light, restricting the available information to two dimensions. Recent advances in tissue-clearing techniques enable imaging of fluorescently labeled organs and entire organisms on a cellular level in three dimensions without the need of sectioning. Volume imaging of immunolabeled and cleared tissues started a new era of systems biology, because these techniques provide information on connectivity and circuits, especially in structures with projections in three dimensions such as vascular or nervous systems. The variety of published clearing protocols allows the imaging of every organ with a single exception: the eye. Whole-eye clearing approaches were unsuccessful so far due to the strong pigmentation of the retinal pigment epithelium. Here, we present a new protocol that combines a highly effective melanin bleaching step with solvent-based clearing, termed EyeCi. The protocol is compatible with immunolabeling as demonstrated by the visualization of ocular and retinal vasculature in the intact mouse eye by means of light-sheet fluorescence microscopy. This novel protocol is rapid (1 week) and inexpensive, hence allowing high-throughput, high resolution analysis of vascular architecture of healthy and diseased eyes, in its native, three-dimensional organization within intact eyeballs. Volume imaging of whole cleared eyeballs further enables three-dimensional surface reconstruction and automated quantification of choroidal and retinal vasculature extending ocular imaging to a global level. Thus, EyeCi represents an extension to state-of-the-art light microscopy techniques and is potentially suitable for the investigation of vascular leakage or neovascularization processes.
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Affiliation(s)
- Yoshiyuki Henning
- Institute of Physiology, University of Duisburg-Essen, 45147, Essen, Germany; Dept. of General Zoology, Faculty of Biology, University of Duisburg-Essen, 45141, Essen, Germany.
| | - Christin Osadnik
- Dept. of General Zoology, Faculty of Biology, University of Duisburg-Essen, 45141, Essen, Germany
| | - Erich Pascal Malkemper
- Dept. of General Zoology, Faculty of Biology, University of Duisburg-Essen, 45141, Essen, Germany; Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Campus-Vienna-Biocenter 1, 1030, Vienna, Austria
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26
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The Different Facades of Retinal and Choroidal Endothelial Cells in Response to Hypoxia. Int J Mol Sci 2018; 19:ijms19123846. [PMID: 30513885 PMCID: PMC6321100 DOI: 10.3390/ijms19123846] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Revised: 11/28/2018] [Accepted: 11/29/2018] [Indexed: 02/06/2023] Open
Abstract
Ocular angiogenic diseases, such as proliferative diabetic retinopathy and neovascular age-related macular degeneration, are associated with severe loss of vision. These pathologies originate from different vascular beds, retinal and choroidal microvasculatures, respectively. The activation of endothelial cells (EC) plays pivotal roles in angiogenesis, often triggered by oxygen deficiency. Hypoxia-inducible factors in ECs mediate the transcription of multiple angiogenic genes, including the canonical vascular endothelial growth factors. ECs show notable heterogeneity in function, structure, and disease, therefore the understanding of retinal/choroidal ECs (REC; CEC) biochemical and molecular responses to hypoxia may offer key insights into tissue-specific vascular targeting treatments. The aim of this review is to discuss the differences spanning between REC and CEC, with focus on their response to hypoxia, which could provide innovative and sustainable strategies for site specific targeting of ocular neovascularization.
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27
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Xu G, Li T, Chen J, Li C, Zhao H, Yao C, Dong H, Wen K, Wang K, Zhao J, Xia Q, Zhou T, Zhang H, Gao P, Li A, Pan X. Autosomal dominant retinitis pigmentosa-associated gene PRPF8 is essential for hypoxia-induced mitophagy through regulating ULK1 mRNA splicing. Autophagy 2018; 14:1818-1830. [PMID: 30103670 DOI: 10.1080/15548627.2018.1501251] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Aged and damaged mitochondria can be selectively degraded by specific autophagic elimination, termed mitophagy. Defects in mitophagy have been increasingly linked to several diseases including neurodegenerative diseases, metabolic diseases and other aging-related diseases. However, the molecular mechanisms of mitophagy are not fully understood. Here, we identify PRPF8 (pre-mRNA processing factor 8), a core component of the spliceosome, as an essential mediator in hypoxia-induced mitophagy from an RNAi screen based on a fluorescent mitophagy reporter, mt-Keima. Knockdown of PRPF8 significantly impairs mitophagosome formation and subsequent mitochondrial clearance through the aberrant mRNA splicing of ULK1, which mediates macroautophagy/autophagy initiation. Importantly, autosomal dominant retinitis pigmentosa (adRP)-associated PRPF8 mutant R2310K is defective in regulating mitophagy. Moreover, knockdown of other adRP-associated splicing factors, including PRPF6, PRPF31 and SNRNP200, also lead to ULK1 mRNA mis-splicing and mitophagy defects. Thus, these findings demonstrate that PRPF8 is essential for mitophagy and suggest that dysregulation of spliceosome-mediated mitophagy may contribute to pathogenesis of retinitis pigmentosa.
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Affiliation(s)
- Guang Xu
- a State Key Laboratory of Proteomics, Institute of Basic Medical Sciences , National Center of Biomedical Analysis , Beijing , China
| | - Ting Li
- a State Key Laboratory of Proteomics, Institute of Basic Medical Sciences , National Center of Biomedical Analysis , Beijing , China
| | - Jiayi Chen
- a State Key Laboratory of Proteomics, Institute of Basic Medical Sciences , National Center of Biomedical Analysis , Beijing , China
| | - Changyan Li
- b State Key Laboratory of Proteomics, Beijing Proteome Research Center , Beijing Institute of Lifeomics , Beijing , China
| | - Haixin Zhao
- a State Key Laboratory of Proteomics, Institute of Basic Medical Sciences , National Center of Biomedical Analysis , Beijing , China
| | - Chengcheng Yao
- a State Key Laboratory of Proteomics, Institute of Basic Medical Sciences , National Center of Biomedical Analysis , Beijing , China
| | - Hua Dong
- a State Key Laboratory of Proteomics, Institute of Basic Medical Sciences , National Center of Biomedical Analysis , Beijing , China
| | - Kaiqing Wen
- a State Key Laboratory of Proteomics, Institute of Basic Medical Sciences , National Center of Biomedical Analysis , Beijing , China
| | - Kai Wang
- a State Key Laboratory of Proteomics, Institute of Basic Medical Sciences , National Center of Biomedical Analysis , Beijing , China
| | - Jie Zhao
- a State Key Laboratory of Proteomics, Institute of Basic Medical Sciences , National Center of Biomedical Analysis , Beijing , China
| | - Qing Xia
- a State Key Laboratory of Proteomics, Institute of Basic Medical Sciences , National Center of Biomedical Analysis , Beijing , China
| | - Tao Zhou
- a State Key Laboratory of Proteomics, Institute of Basic Medical Sciences , National Center of Biomedical Analysis , Beijing , China
| | - Huafeng Zhang
- c Hefei National Laboratory for Physical Sciences at Microscale, the CAS Key Laboratory of Innate Immunity and Chronic Disease, Innovation Center for Cell Signaling Network, School of Life Sciences , University of Science and Technology of China , Hefei , China
| | - Ping Gao
- c Hefei National Laboratory for Physical Sciences at Microscale, the CAS Key Laboratory of Innate Immunity and Chronic Disease, Innovation Center for Cell Signaling Network, School of Life Sciences , University of Science and Technology of China , Hefei , China
| | - Ailing Li
- a State Key Laboratory of Proteomics, Institute of Basic Medical Sciences , National Center of Biomedical Analysis , Beijing , China
| | - Xin Pan
- a State Key Laboratory of Proteomics, Institute of Basic Medical Sciences , National Center of Biomedical Analysis , Beijing , China.,d State Key Laboratory of Toxicology and Medical Countermeasures , Beijing Institute of Pharmacology and Toxicology , Beijing , China
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