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Liu D, Du J, Xie H, Tian H, Lu L, Zhang C, Xu GT, Zhang J. Wnt5a/β-catenin-mediated epithelial-mesenchymal transition: a key driver of subretinal fibrosis in neovascular age-related macular degeneration. J Neuroinflammation 2024; 21:75. [PMID: 38532410 DOI: 10.1186/s12974-024-03068-w] [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: 12/01/2023] [Accepted: 03/18/2024] [Indexed: 03/28/2024] Open
Abstract
BACKGROUND Neovascular age-related macular degeneration (nAMD), accounts for up to 90% of AMD-associated vision loss, ultimately resulting in the formation of fibrotic scar in the macular region. The pathogenesis of subretinal fibrosis in nAMD involves the process of epithelial-mesenchymal transition (EMT) occurring in retinal pigment epithelium (RPE). Here, we aim to investigate the underlying mechanisms involved in the Wnt signaling during the EMT of RPE cells and in the pathological process of subretinal fibrosis secondary to nAMD. METHODS In vivo, the induction of subretinal fibrosis was performed in male C57BL/6J mice through laser photocoagulation. Either FH535 (a β-catenin inhibitor) or Box5 (a Wnt5a inhibitor) was intravitreally administered on the same day or 14 days following laser induction. The RPE-Bruch's membrane-choriocapillaris complex (RBCC) tissues were collected and subjected to Western blot analysis and immunofluorescence to examine fibrovascular and Wnt-related markers. In vitro, transforming growth factor beta 1 (TGFβ1)-treated ARPE-19 cells were co-incubated with or without FH535, Foxy-5 (a Wnt5a-mimicking peptide), Box5, or Wnt5a shRNA, respectively. The changes in EMT- and Wnt-related signaling molecules, as well as cell functions were assessed using qRT-PCR, nuclear-cytoplasmic fractionation assay, Western blot, immunofluorescence, scratch assay or transwell migration assay. The cell viability of ARPE-19 cells was determined using Cell Counting Kit (CCK)-8. RESULTS The in vivo analysis demonstrated Wnt5a/ROR1, but not Wnt3a, was upregulated in the RBCCs of the laser-induced CNV mice compared to the normal control group. Intravitreal injection of FH535 effectively reduced Wnt5a protein expression. Both FH535 and Box5 effectively attenuated subretinal fibrosis and EMT, as well as the activation of β-catenin in laser-induced CNV mice, as evidenced by the significant reduction in areas positive for fibronectin, alpha-smooth muscle actin (α-SMA), collagen I, and active β-catenin labeling. In vitro, Wnt5a/ROR1, active β-catenin, and some other Wnt signaling molecules were upregulated in the TGFβ1-induced EMT cell model using ARPE-19 cells. Co-treatment with FH535, Box5, or Wnt5a shRNA markedly suppressed the activation of Wnt5a, nuclear translocation of active β-catenin, as well as the EMT in TGFβ1-treated ARPE-19 cells. Conversely, treatment with Foxy-5 independently resulted in the activation of abovementioned molecules and subsequent induction of EMT in ARPE-19 cells. CONCLUSIONS Our study reveals a reciprocal activation between Wnt5a and β-catenin to mediate EMT as a pivotal driver of subretinal fibrosis in nAMD. This positive feedback loop provides valuable insights into potential therapeutic strategies to treat subretinal fibrosis in nAMD patients.
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Affiliation(s)
- Dandan Liu
- Department of Ophthalmology of Tongji Hospital and Laboratory of Clinical and Visual Sciences of Tongji Eye Institute, School of Medicine, Tongji University, Shanghai, China
| | - Jingxiao Du
- Department of Ophthalmology, Shanghai General Hospital (Shanghai First People's Hospital), Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Shanghai Key Laboratory of Ocular Fundus Diseases, National Clinical Research Center for Eye Diseases, Shanghai Engineering Center for Visual Science and Photomedicine, Shanghai Engineering Center for Precise Diagnosis and Treatment of Eye Diseases, Shanghai Eye Research Institute, Shanghai, China
| | - Hai Xie
- Department of Ophthalmology, Shanghai General Hospital (Shanghai First People's Hospital), Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Shanghai Key Laboratory of Ocular Fundus Diseases, National Clinical Research Center for Eye Diseases, Shanghai Engineering Center for Visual Science and Photomedicine, Shanghai Engineering Center for Precise Diagnosis and Treatment of Eye Diseases, Shanghai Eye Research Institute, Shanghai, China
| | - Haibin Tian
- Department of Ophthalmology of Tongji Hospital and Laboratory of Clinical and Visual Sciences of Tongji Eye Institute, School of Medicine, Tongji University, Shanghai, China
| | - Lixia Lu
- Department of Ophthalmology of Tongji Hospital and Laboratory of Clinical and Visual Sciences of Tongji Eye Institute, School of Medicine, Tongji University, Shanghai, China
| | - Chaoyang Zhang
- Department of Ophthalmology, Shanghai General Hospital (Shanghai First People's Hospital), Shanghai Jiao Tong University School of Medicine, Shanghai, China.
- Shanghai Key Laboratory of Ocular Fundus Diseases, National Clinical Research Center for Eye Diseases, Shanghai Engineering Center for Visual Science and Photomedicine, Shanghai Engineering Center for Precise Diagnosis and Treatment of Eye Diseases, Shanghai Eye Research Institute, Shanghai, China.
| | - Guo-Tong Xu
- Department of Ophthalmology of Tongji Hospital and Laboratory of Clinical and Visual Sciences of Tongji Eye Institute, School of Medicine, Tongji University, Shanghai, China.
| | - Jingfa Zhang
- Department of Ophthalmology, Shanghai General Hospital (Shanghai First People's Hospital), Shanghai Jiao Tong University School of Medicine, Shanghai, China.
- Shanghai Key Laboratory of Ocular Fundus Diseases, National Clinical Research Center for Eye Diseases, Shanghai Engineering Center for Visual Science and Photomedicine, Shanghai Engineering Center for Precise Diagnosis and Treatment of Eye Diseases, Shanghai Eye Research Institute, Shanghai, China.
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Wu X, Yang X, Dai X, Chen X, Shen M, Dai J, Yuan F, Wang L, Yuan Y, Feng Y. 5-Aza-2'-Deoxycytidine Ameliorates Choroidal Neovascularization by Inhibiting the Wnt/β-Catenin Signaling Pathway. Invest Ophthalmol Vis Sci 2024; 65:23. [PMID: 38345554 PMCID: PMC10866157 DOI: 10.1167/iovs.65.2.23] [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: 08/28/2023] [Accepted: 01/28/2024] [Indexed: 02/15/2024] Open
Abstract
Purpose Choroidal neovascularization (CNV) can constitute the final pathology of many ocular diseases and result in severe vision loss. Studies have demonstrated that DNA methylation is critical in retinal development, aging, and disorders. The current work investigated the effects and underlying mechanism of 5-Aza-2'-deoxycytidine (5-aza-dC), a suppressor of DNA methylation, in the pathological progression of CNV. Methods The DNA methylation profiles of retinal pigment epithelial (RPE)/choroidal complexes in normal and laser-induced CNV mice were assessed by Arraystar Mouse RefSeq Promoter Arrays. The CNV area and blood flow density and intensity were observed by optical coherence tomography angiography, and fluorescence leakage was examined by fundus fluorescein angiography in CNV mice with systemic administration of 5-aza-dC. The effects of 5-aza-dC on the biological functions of bEnd.3 cells were estimated by related assays. Notum gene promoter methylation was measured using bisulfite sequencing PCR. Methyltransferases and Wnt signaling-related genes were detected in animal and cell culture experiments by real-time PCR and immunoblot. Results Methyltransferases were upregulated, but Notum (a secretion inhibitor of Wnt signaling) was downregulated in the RPE/choroidal complexes of mice with experimental CNV. Intraperitoneal injection of 5-aza-dC inactivated the Wnt pathway and ameliorated the lesion area and the intensity and density of blood flow, as well as the degree of leakage in CNV. In vitro, vascular endothelial growth factor A (VEGFA) stimulation promoted methyltransferases expression and suppressed Notum expression, consequently activating Wnt signaling, whereas exogenous 5-aza-dC reversed VEGFA-induced hyperpermeability, proliferation, migration, and tube formation in bEnd.3 cells via demethylation of Notum promoter. Conclusions We observed that 5-aza-dC attenuates the growth of CNV by inhibiting the Wnt signaling pathway via promoter demethylation of the Wnt antagonist Notum. These findings provide a theoretical basis for methylation-based treatment with the Notum gene as a potential target for CNV treatment.
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Affiliation(s)
- Xinyuan Wu
- Department of Ophthalmology, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Xi Yang
- Department of Ophthalmology, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Xiaochan Dai
- Department of Ophthalmology, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Xiuping Chen
- Department of Ophthalmology, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Minqian Shen
- Department of Ophthalmology, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Jinhui Dai
- Department of Ophthalmology, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Fei Yuan
- Department of Ophthalmology, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Liyang Wang
- Department of Ophthalmology, Shanghai Geriatric Medical Center, Shanghai, China
| | - Yuanzhi Yuan
- Department of Ophthalmology, Zhongshan Hospital, Fudan University, Shanghai, China
- Department of Ophthalmology, Zhongshan Hospital (Xiamen), Fudan University, Xiamen, China
| | - Yifan Feng
- Department of Ophthalmology, Zhongshan Hospital, Fudan University, Shanghai, China
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Park JE, Lee J, Ok S, Byun S, Chang EJ, Yoon SE, Kim YJ, Kang MJ. Wg/Wnt1 and Erasp link ER stress to proapoptotic signaling in an autosomal dominant retinitis pigmentosa model. Exp Mol Med 2023:10.1038/s12276-023-01044-7. [PMID: 37464094 PMCID: PMC10394004 DOI: 10.1038/s12276-023-01044-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 04/11/2023] [Accepted: 04/17/2023] [Indexed: 07/20/2023] Open
Abstract
The endoplasmic reticulum (ER) is a subcellular organelle essential for cellular homeostasis. Perturbation of ER functions due to various conditions can induce apoptosis. Chronic ER stress has been implicated in a wide range of diseases, including autosomal dominant retinitis pigmentosa (ADRP), which is characterized by age-dependent retinal degeneration caused by mutant rhodopsin alleles. However, the signaling pathways that mediate apoptosis in response to ER stress remain poorly understood. In this study, we performed an unbiased in vivo RNAi screen with a Drosophila ADRP model and found that Wg/Wnt1 mediated apoptosis. Subsequent transcriptome analysis revealed that ER stress-associated serine protease (Erasp), which has been predicted to show serine-type endopeptidase activity, was a downstream target of Wg/Wnt1 during ER stress. Furthermore, knocking down Erasp via RNAi suppressed apoptosis induced by mutant rhodopsin-1 (Rh-1P37H) toxicity, alleviating retinal degeneration in the Drosophila ADRP model. In contrast, overexpression of Erasp resulted in enhanced caspase activity in Drosophila S2 cells treated with apoptotic inducers and the stabilization of the initiator caspase Dronc (Death regulator Nedd2-like caspase) by stimulating DIAP1 (Drosophila inhibitor of apoptosis protein 1) degradation. These findings helped identify a novel cell death signaling pathway involved in retinal degeneration in an autosomal dominant retinitis pigmentosa model.
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Affiliation(s)
- Jung-Eun Park
- Department of Pharmacology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, 05505, Republic of Korea
| | - Jiyoun Lee
- School of Biopharmaceutical and Medical Sciences, Sungshin University, Seoul, 01133, Republic of Korea
| | - Soonhyuck Ok
- Department of Pharmacology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, 05505, Republic of Korea
| | - Seunghee Byun
- Department of Pharmacology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, 05505, Republic of Korea
| | - Eun-Ju Chang
- Department of Biochemistry and Molecular Biology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, 05505, Republic of Korea
- Biomedical Research Center, Asan Institute for Life Sciences, Asan Medical Center, 88, Olympic-ro 43-gil, Songpa-gu, Seoul, 05505, Republic of Korea
| | - Sung-Eun Yoon
- Korea Drosophila Resource Center, Gwangju Institute of Science and Technology (GIST), 123 Cheomdangwagi-ro, Buk-gu, Gwangju, 61005, Republic of Korea
| | - Young-Joon Kim
- School of Life Sciences, Gwangju Institute of Science and Technology (GIST), 123 Cheomdangwagi-ro, Buk-gu, Gwangju, 61005, Republic of Korea
| | - Min-Ji Kang
- Department of Pharmacology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, 05505, Republic of Korea.
- Biomedical Research Center, Asan Institute for Life Sciences, Asan Medical Center, 88, Olympic-ro 43-gil, Songpa-gu, Seoul, 05505, Republic of Korea.
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Shah R, Amador C, Chun ST, Ghiam S, Saghizadeh M, Kramerov AA, Ljubimov AV. Non-canonical Wnt signaling in the eye. Prog Retin Eye Res 2023; 95:101149. [PMID: 36443219 PMCID: PMC10209355 DOI: 10.1016/j.preteyeres.2022.101149] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2022] [Revised: 11/12/2022] [Accepted: 11/17/2022] [Indexed: 11/27/2022]
Abstract
Wnt signaling comprises a group of complex signal transduction pathways that play critical roles in cell proliferation, differentiation, and apoptosis during development, as well as in stem cell maintenance and adult tissue homeostasis. Wnt pathways are classified into two major groups, canonical (β-catenin-dependent) or non-canonical (β-catenin-independent). Most previous studies in the eye have focused on canonical Wnt signaling, and the role of non-canonical signaling remains poorly understood. Additionally, the crosstalk between canonical and non-canonical Wnt signaling in the eye has hardly been explored. In this review, we present an overview of available data on ocular non-canonical Wnt signaling, including developmental and functional aspects in different eye compartments. We also discuss important changes of this signaling in various ocular conditions, such as keratoconus, aniridia-related keratopathy, diabetes, age-related macular degeneration, optic nerve damage, pathological angiogenesis, and abnormalities in the trabecular meshwork and conjunctival cells, and limbal stem cell deficiency.
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Affiliation(s)
- Ruchi Shah
- Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA, USA; Regenerative Medicine Institute Eye Program, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Cynthia Amador
- Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA, USA; Regenerative Medicine Institute Eye Program, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Steven T Chun
- Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA, USA; Regenerative Medicine Institute Eye Program, Cedars-Sinai Medical Center, Los Angeles, CA, USA; University of California Los Angeles, Los Angeles, CA, USA
| | - Sean Ghiam
- Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA, USA; Regenerative Medicine Institute Eye Program, Cedars-Sinai Medical Center, Los Angeles, CA, USA; Sackler School of Medicine, New York State/American Program of Tel Aviv University, Tel Aviv, Israel
| | - Mehrnoosh Saghizadeh
- Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA, USA; Regenerative Medicine Institute Eye Program, Cedars-Sinai Medical Center, Los Angeles, CA, USA; David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, USA
| | - Andrei A Kramerov
- Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA, USA; Regenerative Medicine Institute Eye Program, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Alexander V Ljubimov
- Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA, USA; Regenerative Medicine Institute Eye Program, Cedars-Sinai Medical Center, Los Angeles, CA, USA; David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, USA; Neurosurgery, Cedars-Sinai Medical Center, Los Angeles, CA, USA.
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5
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Xue Z, Yuan J, Chen F, Yao Y, Xing S, Yu X, Li K, Wang C, Bao J, Qu J, Su J, Chen H. Genome-wide association meta-analysis of 88,250 individuals highlights pleiotropic mechanisms of five ocular diseases in UK Biobank. EBioMedicine 2022; 82:104161. [PMID: 35841873 PMCID: PMC9297108 DOI: 10.1016/j.ebiom.2022.104161] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Revised: 06/28/2022] [Accepted: 06/29/2022] [Indexed: 12/26/2022] Open
Abstract
BACKGROUND Ocular diseases may exhibit common clinical symptoms and epidemiological comorbidity. However, the extent of pleiotropic mechanisms across ocular diseases remains unclear. We aim to examine shared genetic etiology in age-related macular degeneration (AMD), diabetic retinopathy (DR), glaucoma, retinal detachment (RD), and myopia. METHODS We analyzed genome-wide association analyses for the five ocular diseases in 43,877 cases and 44,373 controls of European ancestry from UK Biobank, estimated their genetic relationships (LDSC, GNOVA, and Genomic SEM), and identified pleiotropic loci (ASSET and METASOFT). FINDINGS The genetic correlation of common SNPs revealed a meaningful genetic structure within these diseases, identifying genetic correlations between AMD, DR, and glaucoma. Cross-trait meta-analysis identified 23 pleiotropic loci associated with at least two ocular diseases and 14 loci unique to individual disorders (non-pleiotropic). We found that the genes associated with these shared genetic loci are involved in neuron differentiation (P = 8.80 × 10-6) and eye development systems (P = 3.86 × 10-5), and single cell RNA sequencing data reveals their heightened gene expression from multipotent progenitors to other differentiated retinal cells during retina developmental process. INTERPRETATION These results highlighted the potential common genetic architectures among these ocular diseases and can deepen the understanding of the molecular mechanisms underlying the related diseases. FUNDING The National Natural Science Foundation of China (61871294), Zhejiang Provincial Natural Science Foundation of China (LR19C060001), and the Scientific Research Foundation for Talents of Wenzhou Medical University (QTJ18023).
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Affiliation(s)
- Zhengbo Xue
- Eye Hospital and School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou 325027, Zhejiang, China
| | - Jian Yuan
- Eye Hospital and School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou 325027, Zhejiang, China
| | - Fukun Chen
- Eye Hospital and School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou 325027, Zhejiang, China
| | - Yinghao Yao
- Wenzhou Institute, University of Chinese Academy of Sciences, Wenzhou 325105, Zhejiang, China
| | - Shilai Xing
- Eye Hospital and School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou 325027, Zhejiang, China
| | - Xiangyi Yu
- Eye Hospital and School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou 325027, Zhejiang, China
| | - Kai Li
- Wenzhou Institute, University of Chinese Academy of Sciences, Wenzhou 325105, Zhejiang, China
| | - Chenxiao Wang
- Eye Hospital and School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou 325027, Zhejiang, China
| | - Jinhua Bao
- Eye Hospital and School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou 325027, Zhejiang, China
| | - Jia Qu
- Eye Hospital and School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou 325027, Zhejiang, China; Oujiang Laboratory, Zhejiang Lab for Regenerative Medicine, Vision and Brain Health, Wenzhou 325101, Zhejiang, China
| | - Jianzhong Su
- Eye Hospital and School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou 325027, Zhejiang, China; Oujiang Laboratory, Zhejiang Lab for Regenerative Medicine, Vision and Brain Health, Wenzhou 325101, Zhejiang, China; Wenzhou Institute, University of Chinese Academy of Sciences, Wenzhou 325105, Zhejiang, China.
| | - Hao Chen
- Eye Hospital and School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou 325027, Zhejiang, China.
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Vallée A. Curcumin and Wnt/β‑catenin signaling in exudative age‑related macular degeneration (Review). Int J Mol Med 2022; 49:79. [PMID: 35445729 PMCID: PMC9083851 DOI: 10.3892/ijmm.2022.5135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Accepted: 03/11/2022] [Indexed: 11/06/2022] Open
Abstract
Curcumin is a natural product widely used due to its pharmacological effects. Nevertheless, only a limited number of studies concerning the effects of curcumin on exudative age‑related macular degeneration (AMD) is currently available. Since ophthalmic diseases, including exudative AMD, have a marked impact on public health, the prevention and therapy of ophthalmic disorders remain of increasing concern. Exudative AMD is characterized by choroidal neovascularization (CNV) invading the subretinal space, ultimately enhancing exudation and hemorrhaging. The exudative AMD subtype corresponds to 10 to 15% of cases of macular degeneration; however, the occurrence of this subtype has been reported as the major cause of vision loss and blindness, with the occurrence of CNV being responsible for 80% of the cases with vision loss. In CNV increased expression of VEGF has been observed, stimulated by the overactivation of Wnt/β‑catenin signaling pathway. The stimulation of the Wnt/β‑catenin signaling pathway is responsible for the activation of several cellular mechanisms, simultaneously enhancing inflammation, oxidative stress and angiogenesis in numerous diseases, including ophthalmic disorders. Some studies have previously demonstrated the possible advantage of the use of curcumin for the inhibition of Wnt/β‑catenin signaling. In the present review article, the different mechanisms of curcumin are described concerning its effects on oxidative stress, inflammation and angiogenesis in exudative AMD, by interacting with Wnt/β‑catenin signaling.
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Affiliation(s)
- Alexandre Vallée
- Department of Epidemiology-Data-Biostatistics, Delegation of Clinical Research and Innovation (DRCI), Foch Hospital, 92150 Suresnes, France
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7
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Bats ML, Peghaire C, Delobel V, Dufourcq P, Couffinhal T, Duplàa C. Wnt/frizzled Signaling in Endothelium: A Major Player in Blood-Retinal- and Blood-Brain-Barrier Integrity. Cold Spring Harb Perspect Med 2022; 12:a041219. [PMID: 35074794 PMCID: PMC9121893 DOI: 10.1101/cshperspect.a041219] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The Wnt/frizzled signaling pathway is one of the major regulators of endothelial biology, controlling key cellular activities. Many secreted Wnt ligands have been identified and can initiate diverse signaling via binding to a complex set of Frizzled (Fzd) transmembrane receptors and coreceptors. Roughly, Wnt signaling is subdivided into two pathways: the canonical Wnt/β-catenin signaling pathway whose main downstream effector is the transcriptional coactivator β-catenin, and the noncanonical Wnt signaling pathway, which is subdivided into the Wnt/Ca2+ pathway and the planar cell polarity pathway. Here, we will focus on its cross talk with other angiogenic pathways and on its role in blood-retinal- and blood-brain-barrier formation and its maintenance in a differentiated state. We will unravel how retinal vascular pathologies and neurovascular degenerative diseases result from disruption of the Wnt pathway related to vascular instability, and highlight current research into therapeutic options.
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Affiliation(s)
- Marie-Lise Bats
- Univ. Bordeaux, Inserm, UMR1034, Biology of Cardiovascular Diseases, F-33600 Pessac, France
- Department of Biochemistry, Pellegrin Hospital, University Hospital of Bordeaux, 33076 Bordeaux Cedex, France
| | - Claire Peghaire
- Univ. Bordeaux, Inserm, UMR1034, Biology of Cardiovascular Diseases, F-33600 Pessac, France
| | - Valentin Delobel
- Univ. Bordeaux, Inserm, UMR1034, Biology of Cardiovascular Diseases, F-33600 Pessac, France
| | - Pascale Dufourcq
- Univ. Bordeaux, Inserm, UMR1034, Biology of Cardiovascular Diseases, F-33600 Pessac, France
| | - Thierry Couffinhal
- Univ. Bordeaux, Inserm, UMR1034, Biology of Cardiovascular Diseases, F-33600 Pessac, France
- Centre d'exploration, de prévention et de traitement de l'athérosclérose (CEPTA), CHU Bordeaux, 33000 Bordeaux, France
| | - Cécile Duplàa
- Univ. Bordeaux, Inserm, UMR1034, Biology of Cardiovascular Diseases, F-33600 Pessac, France
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8
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Ma X, Takahashi Y, Wu W, Chen J, Dehdarani M, Liang W, Shin YH, Benyajati S, Ma JX. Soluble very low-density lipoprotein receptor (sVLDLR) inhibits fibrosis in neovascular age-related macular degeneration. FASEB J 2021; 35:e22058. [PMID: 34820908 PMCID: PMC9131420 DOI: 10.1096/fj.202101334r] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Revised: 10/29/2021] [Accepted: 11/08/2021] [Indexed: 01/17/2023]
Abstract
Subretinal fibrosis is a key pathological feature in neovascular age‐related macular degeneration (nAMD). Previously, we identified soluble very low‐density lipoprotein receptor (sVLDLR) as an endogenous Wnt signaling inhibitor. This study investigates whether sVLDLR plays an anti‐fibrogenic role in nAMD models, including Vldlr−/− mice and laser‐induced choroidal neovascularization (CNV). We found that fibrosis factors including P‐Smad2/3, α‐SMA, and CTGF were upregulated in the subretinal area of Vldlr−/− mice and the laser‐induced CNV model. The antibody blocking Wnt co‐receptor LRP6 significantly attenuated the overexpression of fibrotic factors in these two models. Moreover, there was a significant reduction of sVLDLR in the interphotoreceptor matrix (IPM) in the laser‐induced CNV model. A transgenic strain (sVLDLR‐Tg) with sVLDLR overexpression in the IPM was generated. Overexpression of sVLDLR ameliorated the profibrotic changes in the subretinal area of the laser‐induced CNV model. In addition, Wnt and TGF‐β signaling synergistically promoted fibrogenesis in human primary retinal pigment epithelium (RPE) cells. CRISPR/Cas9‐mediated LRP6 gene knockout (KO) attenuated this synergistic effect. The disruption of VLDLR expression promoted, while the overexpression of sVLDLR inhibited TGF‐β‐induced fibrosis. These findings suggest that overactivated Wnt signaling enhances the TGF‐β pathway in subretinal fibrosis. sVLDLR confers an antifibrotic effect, at least partially, through the inhibition of Wnt signaling and thus, has therapeutic potential for fibrosis.
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Affiliation(s)
- Xiang Ma
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | - Yusuke Takahashi
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | - Wenjing Wu
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | - Jianglei Chen
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | - Marcus Dehdarani
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | - Wentao Liang
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | - Young-Hwa Shin
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | - Siribhinya Benyajati
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | - Jian-Xing Ma
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
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Zhong Y, Wang K, Zhang Y, Yin Q, Li S, Wang J, Zhang X, Han H, Yao K. Ocular Wnt/β-Catenin Pathway Inhibitor XAV939-Loaded Liposomes for Treating Alkali-Burned Corneal Wound and Neovascularization. Front Bioeng Biotechnol 2021; 9:753879. [PMID: 34765592 PMCID: PMC8576519 DOI: 10.3389/fbioe.2021.753879] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Accepted: 09/20/2021] [Indexed: 12/12/2022] Open
Abstract
Corneal wound involves a series of complex and coordinated physiological processes, leading to persistent epithelial defects and opacification. An obstacle in the treatment of ocular diseases is poor drug delivery and maintenance. In this study, we constructed a Wnt/β-catenin pathway inhibitor, XAV939-loaded liposome (XAV939 NPs), and revealed its anti-inflammatory and antiangiogenic effects. The XAV939 NPs possessed excellent biocompatibility in corneal epithelial cells and mouse corneas. In vitro corneal wound healing assays demonstrated their antiangiogenic effect, and LPS-induced expressions of pro-inflammatory genes of IL-1β, IL-6, and IL-17α were significantly suppressed by XAV939 NPs. In addition, the XAV939 NPs significantly ameliorated alkali-burned corneas with slight corneal opacity, reduced neovascularization, and faster recovery, which were attributed to the decreased gene expressions of angiogenic and inflammatory cytokines. The findings supported the potential of XAV939 NPs in ameliorating corneal wound and suppressing neovascularization, providing evidence for their clinical application in ocular vascular diseases.
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Affiliation(s)
- Yueyang Zhong
- Eye Center, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
- Zhejiang Provincial Key Lab of Ophthalmology, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Kai Wang
- Eye Center, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
- Zhejiang Provincial Key Lab of Ophthalmology, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Yin Zhang
- Eye Center, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
- Zhejiang Provincial Key Lab of Ophthalmology, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Qichuan Yin
- Eye Center, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
- Zhejiang Provincial Key Lab of Ophthalmology, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Su Li
- Eye Center, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
- Zhejiang Provincial Key Lab of Ophthalmology, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Jiaming Wang
- The First Affiliated Hospital, School of Public Health, Institute of Translational Medicine, State Key Laboratory of Experimental Hematology, School of Medicine, Zhejiang University, Hangzhou, China
| | - Xiaobo Zhang
- Eye Center, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
- Zhejiang Provincial Key Lab of Ophthalmology, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Haijie Han
- Eye Center, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
- Zhejiang Provincial Key Lab of Ophthalmology, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Ke Yao
- Eye Center, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
- Zhejiang Provincial Key Lab of Ophthalmology, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
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10
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Ma X, Takahashi Y, Wu W, Liang W, Chen J, Chakraborty D, Li Y, Du Y, Benyajati S, Ma JX. ADAM17 mediates ectodomain shedding of the soluble VLDL receptor fragment in the retinal epithelium. J Biol Chem 2021; 297:101185. [PMID: 34509473 PMCID: PMC8487060 DOI: 10.1016/j.jbc.2021.101185] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Revised: 08/27/2021] [Accepted: 09/07/2021] [Indexed: 11/19/2022] Open
Abstract
Very low-density lipoprotein receptor (VLDLR) is a multifunctional transmembrane protein. Beyond the function of the full-length VLDLR in lipid transport, the soluble ectodomain of VLDLR (sVLDLR) confers anti-inflammatory and antiangiogenic roles in ocular tissues through inhibition of canonical Wnt signaling. However, it remains unknown how sVLDLR is shed into the extracellular space. In this study, we present the first evidence that a disintegrin and metalloprotease 17 (ADAM17) is responsible for sVLDLR shedding in human retinal pigment epithelium cells using pharmacological and genetic approaches. Among selected proteinase inhibitors, an ADAM17 inhibitor demonstrated the most potent inhibitory effect on sVLDLR shedding. siRNA-mediated knockdown or CRISPR/Cas9-mediated KO of ADAM17 diminished, whereas plasmid-mediated overexpression of ADAM17 promoted sVLDLR shedding. The amount of shed sVLDLR correlated with an inhibitory effect on the Wnt signaling pathway. Consistent with these in vitro findings, intravitreal injection of an ADAM17 inhibitor reduced sVLDLR levels in the extracellular matrix in the mouse retina. In addition, our results demonstrated that ADAM17 cleaved VLDLR only in cells coexpressing these proteins, suggesting that shedding occurs in a cis manner. Moreover, our study demonstrated that aberrant activation of Wnt signaling was associated with decreased sVLDLR levels, along with downregulation of ADAM17 in ocular tissues of an age-related macular degeneration model. Taken together, our observations reveal the mechanism underlying VLDLR cleavage and identify a potential therapeutic target for the treatment of disorders associated with dysregulation of Wnt signaling.
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Affiliation(s)
- Xiang Ma
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | - Yusuke Takahashi
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | - Wenjing Wu
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | - Wentao Liang
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | - Jianglei Chen
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | - Dibyendu Chakraborty
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | - Yangxiong Li
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | - Yanhong Du
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | - Siribhinya Benyajati
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | - Jian-Xing Ma
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA.
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11
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Singh HD, Ma JX, Takahashi Y. Distinct roles of LRP5 and LRP6 in Wnt signaling regulation in the retina. Biochem Biophys Res Commun 2021; 545:8-13. [PMID: 33545636 DOI: 10.1016/j.bbrc.2021.01.068] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Accepted: 01/20/2021] [Indexed: 12/11/2022]
Abstract
Dysregulation of Wnt signaling is implicated in multiple ocular disorders. The roles of Wnt co-receptors LRP5 and LRP6 in Wnt signaling regulation remain elusive, as most retinal cells express both of the co-receptors. To address this question, LRP5 and LRP6 were individually knocked-out in a human retinal pigment epithelium cell line using the CRISPR-Cas9 technology. Wnt signaling activity induced by various Wnt ligands was measured using wild-type and the KO cell lines. The results identified three groups of Wnt ligands based on their co-receptor specificity: 1) activation of Wnt signaling only through LRP6, 2) through both LRP5 and LRP6 and 3) predominantly through LRP5. These results indicate that LRP5 and LRP6 have differential roles in Wnt signaling regulation.
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Affiliation(s)
- Harminder D Singh
- Department of Physiology, The University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Jian-Xing Ma
- Department of Physiology, The University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA; Harold Hamm Diabetes Center, The University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Yusuke Takahashi
- Department of Physiology, The University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA; Harold Hamm Diabetes Center, The University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA.
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12
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Fenofibrate prevents iron induced activation of canonical Wnt/β-catenin and oxidative stress signaling in the retina. NPJ Aging Mech Dis 2020; 6:12. [PMID: 33145027 PMCID: PMC7599211 DOI: 10.1038/s41514-020-00050-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Accepted: 10/09/2020] [Indexed: 12/20/2022] Open
Abstract
Accumulating evidence strongly implicates iron in the pathogenesis of aging and disease. Iron levels have been found to increase with age in both the human and mouse retinas. We and others have shown that retinal diseases such as age-related macular degeneration and diabetic retinopathy are associated with disrupted iron homeostasis, resulting in retinal iron accumulation. In addition, hereditary disorders due to mutation in one of the iron regulatory genes lead to age dependent retinal iron overload and degeneration. However, our knowledge on whether iron toxicity contributes to the retinopathy is limited. Recently, we reported that iron accumulation is associated with the upregulation of retinal and renal renin-angiotensin system (RAS). Evidences indicate that multiple genes/components of the RAS are targets of Wnt/β-catenin signaling. Interestingly, aberrant activation of Wnt/β-catenin signaling is observed in several degenerative diseases. In the present study, we explored whether iron accumulation regulates canonical Wnt signaling in the retina. We found that in vitro and in vivo iron treatment resulted in the upregulation of Wnt/β-catenin signaling and its downstream target genes including renin-angiotensin system in the retina. We confirmed further that iron activates canonical Wnt signaling in the retina using TOPFlash T-cell factor/lymphoid enhancer factor promoter assay and Axin2-LacZ reporter mouse. The presence of an iron chelator or an antioxidant reversed the iron-mediated upregulation of Wnt/β-catenin signaling in retinal pigment epithelial (RPE) cells. In addition, treatment of RPE cells with peroxisome proliferator-activated receptor (PPAR) α-agonist fenofibrate prevented iron-induced activation of oxidative stress and Wnt/β-catenin signaling by chelating the iron. The role of fenofibrate, an FDA-approved drug for hyperlipidemia, as an iron chelator has potentially significant therapeutic impact on iron associated degenerative diseases.
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13
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Ilimaquinone inhibits neovascular age-related macular degeneration through modulation of Wnt/β-catenin and p53 pathways. Pharmacol Res 2020; 161:105146. [PMID: 32814173 DOI: 10.1016/j.phrs.2020.105146] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Revised: 08/11/2020] [Accepted: 08/11/2020] [Indexed: 11/22/2022]
Abstract
Neovascular age-related macular degeneration (nAMD) is a common cause of irreversible vision loss in the elderly. Anti-vascular endothelial growth factor has been effective in treating pathological ocular neovascularization, but it has limitations including the need for repeated intraocular injections for the maintenance of therapeutic effects in most patients and poor or non-response to this agent in some patients. in vitro cellular studies were conducted using retinal pigment epithelial cell lines (ARPE-19 and hTERT-RPE1), human umbilical vein endothelial cells (HUVECs), and human umbilical vein smooth muscle cells (HUVSMCs). in vivo efficacy of ilimaquinone (IQ) was tested in laser-induced choroidal neovascularization mouse and rabbit models. Tissue distribution study was performed in male C57BL6/J mice. IQ, 4,9-friedodrimane-type sesquiterpenoid isolated from the marine sponge, repressed the expression of angiogenic/inflammatory factors and restored the expression of E-cadherin in retinal pigment epithelial cells by inhibiting the Wnt/β-catenin pathway. In addition, it selectively inhibited proliferation and tube formation of HUVECs by activating the p53 pathway. Topical and intraperitoneal administration of IQ significantly reduced choroidal neovascularization in rabbits and mice with laser-induced choroidal neovascularization. Notably, IQ by the oral route of exposure was highly permeable to the eyes and suppressed abnormal vascular leakage by downregulation of β-catenin and stabilization of p53 in vivo. Our findings demonstrate that IQ functions through regulation of p53 and Wnt/β-catenin pathways with conceivable advantages over existing cytokine-targeted anti-angiogenic therapies.
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14
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Ruan Y, Kato H, Taguchi Y, Yamauchi N, Umeda M. Irradiation by high-intensity red light-emitting diode enhances human bone marrow mesenchymal stem cells osteogenic differentiation and mineralization through Wnt/β-catenin signaling pathway. Lasers Med Sci 2020; 36:55-65. [PMID: 32588268 DOI: 10.1007/s10103-020-03002-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Accepted: 03/25/2020] [Indexed: 01/15/2023]
Abstract
Photobiomodulation therapy (PBMT) using a light-emitting diode (LED) has been employed for various photomedicine studies. The aim of this study was to determine the effects of a high-intensity red LED on the proliferation and osteogenic differentiation of human bone marrow mesenchymal stem cells (BMSCs) and the related mechanism. BMSCs were subjected to high-intensity red LED (LZ1-00R205 Deep Red LED) irradiations for 0 to 40 s with energy densities ranging from 0 to 8 J/cm2. The distance from the LED to the cell layer was 40 mm. The spot size on the target was 4 cm2. Cell proliferation was measured at 3, 24, 48, and 72 h. The effects of LED irradiation on osteogenic differentiation and mineralization were examined with a particular focus on the Wnt/β-catenin signaling pathway. The high-intensity red LED irradiations did not alter BMSC proliferation after 72 h. LED exposure of 6 J/cm2 (30 s) led to significant enhancements of osteogenic differentiation and mineralization. Additionally, the high-intensity LED irradiation induced activation of Wnt/β-catenin. The effects of the high-intensity LED irradiation on BMSC osteogenic differentiation and mineralization were suppressed by treatment with the Wnt/β-catenin inhibitor XAV939. P < 0.05 was considered significant. The results indicate that high-intensity red LED irradiation increases BMSC osteogenic differentiation and mineralization via Wnt/β-catenin activation. Therefore, short duration irradiation with a portable high-intensity LED may be used as a potential approach in hard tissue regeneration therapy.
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Affiliation(s)
- Yaru Ruan
- Department of Periodontology, Osaka Dental University, 8-1, Kuzuhahanazono-cho, Hirakata, Osaka, Japan
| | - Hirohito Kato
- Department of Periodontology, Osaka Dental University, 8-1, Kuzuhahanazono-cho, Hirakata, Osaka, Japan
| | - Yoichiro Taguchi
- Department of Periodontology, Osaka Dental University, 8-1, Kuzuhahanazono-cho, Hirakata, Osaka, Japan.
| | - Nobuhiro Yamauchi
- Department of Periodontology, Osaka Dental University, 8-1, Kuzuhahanazono-cho, Hirakata, Osaka, Japan
| | - Makoto Umeda
- Department of Periodontology, Osaka Dental University, 8-1, Kuzuhahanazono-cho, Hirakata, Osaka, Japan
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15
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Song J, Han D, Lee H, Kim DJ, Cho JY, Park JH, Seok SH. A Comprehensive Proteomic and Phosphoproteomic Analysis of Retinal Pigment Epithelium Reveals Multiple Pathway Alterations in Response to the Inflammatory Stimuli. Int J Mol Sci 2020; 21:ijms21093037. [PMID: 32344885 PMCID: PMC7246457 DOI: 10.3390/ijms21093037] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2020] [Revised: 04/21/2020] [Accepted: 04/23/2020] [Indexed: 12/31/2022] Open
Abstract
Overwhelming and persistent inflammation of retinal pigment epithelium (RPE) induces destructive changes in the retinal environment. However, the precise mechanisms remain unclear. In this study, we aimed to investigate RPE-specific biological and metabolic responses against intense inflammation and identify the molecular characteristics determining pathological progression. We performed quantitative analyses of the proteome and phosphoproteome of the human-derived RPE cell line ARPE-19 after treatment with lipopolysaccharide (LPS) for 45 min or 24 h using the latest isobaric tandem-mass tags (TMTs) labeling approach. This approach led to the identification of 8984 proteins, of which 261 showed a 1.5-fold change in abundance after 24 h of treatment with LPS. A parallel phosphoproteome analysis identified 20,632 unique phosphopeptides from 3207 phosphoproteins with 3103 phosphorylation sites. Integrated proteomic and phosphoproteomic analyses showed significant downregulation of proteins related to mitochondrial respiration and cell cycle checkpoint, while proteins related to lipid metabolism, amino acid metabolism, cell-matrix adhesion, and endoplasmic reticulum (ER) stress were upregulated after LPS stimulation. Further, phosphorylation events in multiple pathways, including MAPKK and Wnt/β-catenin signalings, were identified as involved in LPS-triggered pathobiology. In essence, our findings reveal multiple integrated signals exerted by RPE under inflammation and are expected to give insight into the development of therapeutic interventions for RPE disorders.
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Affiliation(s)
- Juha Song
- Department of Microbiology and Immunology, and Institute of Endemic Disease, Seoul National University College of Medicine, Chongno-gu, Seoul 03080, Korea;
- Department of Laboratory Animal Medicine, College of Veterinary Medicine, Seoul National University, Gwanak-gu, Seoul 08826, Korea
| | - Dohyun Han
- Proteomics Core Facility, Biomedical Research Institute, Seoul National University Hospital, Seoul 03080, Korea; (D.H.); (H.L.)
| | - Heonyi Lee
- Proteomics Core Facility, Biomedical Research Institute, Seoul National University Hospital, Seoul 03080, Korea; (D.H.); (H.L.)
| | - Da Jung Kim
- Department of Clinical Pharmacology and Therapeutics, Seoul National University College of Medicine and Hospital, Seoul 03080, Korea; (D.J.K.); (J.-Y.C.)
- Department of Biomedical Sciences, Seoul National University College of Medicine, Chongno-gu, Seoul 03080, Korea
| | - Joo-Youn Cho
- Department of Clinical Pharmacology and Therapeutics, Seoul National University College of Medicine and Hospital, Seoul 03080, Korea; (D.J.K.); (J.-Y.C.)
- Department of Biomedical Sciences, Seoul National University College of Medicine, Chongno-gu, Seoul 03080, Korea
| | - Jae-Hak Park
- Department of Laboratory Animal Medicine, College of Veterinary Medicine, Seoul National University, Gwanak-gu, Seoul 08826, Korea
- Correspondence: (J.-H.P.); (S.H.S.); Tel.: +82-2-880-1256 (J.-H.P.); +82-2-740-8302 (S.H.S.); Fax: +82-2-763-5206 (S.H.S.)
| | - Seung Hyeok Seok
- Department of Microbiology and Immunology, and Institute of Endemic Disease, Seoul National University College of Medicine, Chongno-gu, Seoul 03080, Korea;
- Department of Biomedical Sciences, Seoul National University College of Medicine, Chongno-gu, Seoul 03080, Korea
- Correspondence: (J.-H.P.); (S.H.S.); Tel.: +82-2-880-1256 (J.-H.P.); +82-2-740-8302 (S.H.S.); Fax: +82-2-763-5206 (S.H.S.)
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16
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Wang Y, Lin W, Ju J. MicroRNA-409-5p promotes retinal neovascularization in diabetic retinopathy. Cell Cycle 2020; 19:1314-1325. [PMID: 32292119 DOI: 10.1080/15384101.2020.1749484] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND Retinal neovascularization, which is characterized by the increased proliferation, migration, and tube formation of retinal microvascular endothelial cells (RMECs), contributes to the progression of diabetic retinopathy (DR). MiR-409-5p has been reported to be upregulated in peripheral blood of DR patients and in vascular endothelial growth factor (VEGF)-induced RMECs. However, the role of miR-409-5p in retinal neovascularization of DR remains unelucidated. METHOD The expression of miR-409-5p was measured in retinal tissues of streptozocin-induced and db/db diabetic mice, in high glucose-induced mouse RMECs (mRMECs), and in vitreous fluid of proliferative DR patients. Antagomir of miR-409-5p was intravitreally injected into diabetic mice. Proliferation, migration, and tube formation were detected using cell counting kit-8 assay, transwell assay, and microscope observation, respectively. Luciferase reporter assay was used to detect the direct interaction between miR-409-5p and peroxisome proliferator-activated receptor-α (PPARα). RESULT MiR-409-5p was upregulated in retinal tissues of diabetic mice, in high glucose-induced mRMECs, and in vitreous fluid of proliferative DR patients. The knockdown of miR-409-5p attenuated retinal neovascularization in vivo. The overexpression of miR-409-5p promotes the proliferation, migration, and tube formation, and increased VEGF expression and secretion, while the knockdown of miR-409-5p suppressed the VEGF-induced retinal neovascularization in vitro. PPARα is a downstream target of miR-409-5p, and PPARα overexpression negated the promotion of miR-409-5p overexpression on the proliferation, migration, and tube formation of mRMECs. CONCLUSION Our findings demonstrated that miR-409-5p acted as a neovasculogenic factor in DR, and anti-miR-409-5p therapy may provide a novel strategy in treating DR.
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Affiliation(s)
- Ying Wang
- Department of Endocrinology, Weihai Municipal Hospital , Weihai, Shandong, China
| | - Wenwen Lin
- Department of Endocrinology, Weihai Municipal Hospital , Weihai, Shandong, China
| | - Jianghua Ju
- Department of Endocrinology, Qilu Hospital of Shandong University (Qingdao) , Qingdao, Shandong, China
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17
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New Developments for Fractional CO2 Resurfacing for Skin Rejuvenation and Scar Reduction. Facial Plast Surg Clin North Am 2020; 28:17-28. [DOI: 10.1016/j.fsc.2019.09.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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18
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Vallée A, Lecarpentier Y, Vallée R, Guillevin R, Vallée JN. Circadian Rhythms in Exudative Age-Related Macular Degeneration: The Key Role of the Canonical WNT/β-Catenin Pathway. Int J Mol Sci 2020; 21:ijms21030820. [PMID: 32012797 PMCID: PMC7037737 DOI: 10.3390/ijms21030820] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Revised: 01/23/2020] [Accepted: 01/27/2020] [Indexed: 02/07/2023] Open
Abstract
Age-related macular degeneration (AMD) is considered as the main worldwide cause of blindness in elderly adults. Exudative AMD type represents 10 to 15% of macular degeneration cases, but is the main cause of vision loss and blindness. Circadian rhythm changes are associated with aging and could further accelerate it. However, the link between circadian rhythms and exudative AMD is not fully understood. Some evidence suggests that dysregulation of circadian functions could be manifestations of diseases or could be risk factors for the development of disease in elderly adults. Biological rhythms are complex systems interacting with the environment and control several physiological pathways. Recent findings have shown that the dysregulation of circadian rhythms is correlated with exudative AMD. One of the main pathways involved in exudative AMD is the canonical WNT/β-catenin pathway. Circadian clocks have a main role in some tissues by driving the circadian expression of genes involved in physiological and metabolic functions. In exudative AMD, the increase of the canonical WNT/β-catenin pathway is enhanced by the dysregulation of circadian rhythms. Exudative AMD progression is associated with major metabolic reprogramming, initiated by aberrant WNT/β-catenin pathway, of aerobic glycolysis. This review focuses on the interest of circadian rhythm dysregulation in exudative AMD through the aberrant upregulation of the canonical WNT/β-catenin pathway.
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Affiliation(s)
- Alexandre Vallée
- DACTIM-MIS, Laboratory of Mathematics and Applications (LMA), UMR CNRS 7348, University of Poitiers, CHU de Poitiers, 86021 Poitiers, France
| | - Yves Lecarpentier
- Centre de Recherche Clinique, Grand Hôpital de l'Est Francilien (GHEF), 77100 Meaux, France
| | - Rodolphe Vallée
- University Hospital Group of Paris-Seine-Saint-Denis, APHP, University of Paris-13 Sorbonne Paris-Cité, 93000 Paris, France
| | - Rémy Guillevin
- DACTIM-MIS, Laboratory of Mathematics and Applications (LMA), UMR CNRS 7348, University of Poitiers, CHU de Poitiers, 86021 Poitiers, France
| | - Jean-Noël Vallée
- CHU Amiens Picardie, University of Picardie Jules Verne (UPJV), 80000 Amiens, France
- Laboratory of Mathematics and Applications (LMA), UMR CNRS 7348, University of Poitiers, 86021 Poitiers, France
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19
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Zhang C, Yin K, Shen YM. Efficacy of fractional carbon dioxide laser therapy for burn scars: a meta-analysis. J DERMATOL TREAT 2019; 32:845-850. [PMID: 31865824 DOI: 10.1080/09546634.2019.1704679] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Cong Zhang
- Department of Burn, Beijing Jishuitan Hospital, Beijing, China
| | - Kai Yin
- Department of Burn, Beijing Jishuitan Hospital, Beijing, China
| | - Yu-ming Shen
- Department of Burn, Beijing Jishuitan Hospital, Beijing, China
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20
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Wang Z, Liu CH, Huang S, Chen J. Wnt Signaling in vascular eye diseases. Prog Retin Eye Res 2018; 70:110-133. [PMID: 30513356 DOI: 10.1016/j.preteyeres.2018.11.008] [Citation(s) in RCA: 119] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Revised: 11/21/2018] [Accepted: 11/28/2018] [Indexed: 12/16/2022]
Abstract
The Wnt signaling pathway plays a pivotal role in vascular morphogenesis in various organs including the eye. Wnt ligands and receptors are key regulators of ocular angiogenesis both during the eye development and in vascular eye diseases. Wnt signaling participates in regulating multiple vascular beds in the eye including regression of the hyaloid vessels, and development of structured layers of vasculature in the retina. Loss-of-function mutations in Wnt signaling components cause rare genetic eye diseases in humans such as Norrie disease, and familial exudative vitreoretinopathy (FEVR) with defective ocular vasculature. On the other hand, experimental studies in more prevalent vascular eye diseases, such as wet age-related macular degeneration (AMD), diabetic retinopathy (DR), retinopathy of prematurity (ROP), and corneal neovascularization, suggest that aberrantly increased Wnt signaling is one of the causations for pathological ocular neovascularization, indicating the potential of modulating Wnt signaling to ameliorate pathological angiogenesis in eye diseases. This review recapitulates the key roles of the Wnt signaling pathway during ocular vascular development and in vascular eye diseases, and pharmaceutical approaches targeting the Wnt signaling as potential treatment options.
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Affiliation(s)
- Zhongxiao Wang
- Department of Ophthalmology, Boston Children's Hospital, Harvard Medical School, 300 Longwood Avenue, Boston, MA, 02115, United States
| | - Chi-Hsiu Liu
- Department of Ophthalmology, Boston Children's Hospital, Harvard Medical School, 300 Longwood Avenue, Boston, MA, 02115, United States
| | - Shuo Huang
- Department of Ophthalmology, Boston Children's Hospital, Harvard Medical School, 300 Longwood Avenue, Boston, MA, 02115, United States
| | - Jing Chen
- Department of Ophthalmology, Boston Children's Hospital, Harvard Medical School, 300 Longwood Avenue, Boston, MA, 02115, United States.
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21
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WNT7A/B promote choroidal neovascularization. Exp Eye Res 2018; 174:107-112. [PMID: 29864439 DOI: 10.1016/j.exer.2018.05.033] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Revised: 05/28/2018] [Accepted: 05/31/2018] [Indexed: 12/19/2022]
Abstract
Perturbations in WNT signaling are associated with congenital eye disorders, including familial exudative vitreoretinopathy and Norrie disease. More recently, activation of the WNT pathway has also been shown to be associated with age-related macular degeneration (AMD). In this study, we identified that in choroidal neovascular membranes from AMD patients, β-catenin is activated specifically in the vascular endothelium, suggesting that WNT promotes pathologic angiogenesis by directly affecting vascular endothelial cells. WNT7B has been shown to be important during eye development for regression of the fetal hyaloid vasculature. However, it has not yet been established whether WNT7A and/or WNT7B are involved in neovascular AMD pathogenesis. Here, we show that WNT7A and WNT7B increase the proliferation of human dermal microvascular endothelial cells in a dose-dependent manner. Both WNT7A and WNT7B also stimulated vascular sprouting from mouse choroidal explants in vitro. To evaluate in vivo relevance, we generated mice systemically deficient in Wnt7a and/or Wnt7b. Genetic deletion of both Wnt7a and Wnt7b decreased the severity of laser injury-induced choroidal neovascularization (CNV), while individual deletion of either Wnt7a or Wnt7b did not have a significant effect on CNV, suggesting that WNT7A and WNT7B have redundant pro-angiogenic roles in vivo. Cumulatively, these findings identify specific WNT isoforms that may play a pathologic role in CNV as observed in patients with neovascular AMD. Although the source of increased WNT7A and/or WNT7B in CNV requires further investigation, WNT signaling may be a potential target for therapeutic intervention if these results are demonstrated to be relevant in human disease.
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22
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Qiu F, Shin Y, Chen D, Cheng R, Chen Q, Zhou K, Larrick JW, Mendelson AR, Ma JX. Anti-angiogenic effect of a humanized antibody blocking the Wnt/β-catenin signaling pathway. Microvasc Res 2018; 119:29-37. [PMID: 29630973 DOI: 10.1016/j.mvr.2018.03.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Revised: 01/14/2018] [Accepted: 03/24/2018] [Indexed: 10/17/2022]
Abstract
PURPOSE Our previous study demonstrated that Mab2F1, a murine monoclonal antibody blocking the Wnt/β-catenin signaling pathway, has beneficial effects on experimental diabetic retinopathy and choroidal neovascularization (NV). The aforementioned antibody has been humanized. This study evaluated effects of the humanized antibody, H1L1, on NV. METHODS H1L1 was evaluated in the alkali burn-induced corneal NV rat model. Rats with corneal NV were injected subconjunctivally with Mab2F1 or H1L1 using non-specific mouse or human IgG as controls. Corneal NV and opacity were evaluated using corneal NV area and inflammatory index. Expression of angiogenic and inflammatory factors and components of the Wnt/β-catenin pathway in both the corneas of the animal model and human corneal epithelial (HCE) cells exposed to Wnt3a conditioned medium (WCM) were determined by Western blotting and a luciferase-based promoter assay. Cytotoxicities of these antibodies were evaluated by MTT assay. RESULTS H1L1 reduced the area of corneal NV and opacity, similar to Mab2F1. Both Mab2F1 and H1L1 down-regulated the overexpression of angiogenic and inflammatory factors including VEGF, TNF-α and ICAM-1, and blocked the aberrant activation of the Wnt/β-catenin pathway as shown by down-regulation of phosphorylated LRP6, total LRP6 and non-phosphorylated β-catenin in the cornea of the NV model and cultured HCE cells exposed to WCM. Both antibodies also inhibited the transcriptional activity of β-catenin induced by WCM in HCE cells. No toxic effects of the antibodies were observed in cultured HCE cells. CONCLUSIONS H1L1 exhibits anti-angiogenic activities through blocking the Wnt/β-catenin pathway.
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Affiliation(s)
- Fangfang Qiu
- Department of Physiology, The University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA.
| | - Younghwa Shin
- Department of Physiology, The University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA.
| | | | - Rui Cheng
- Department of Physiology, The University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA.
| | - Qian Chen
- Department of Physiology, The University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
| | - Kelu Zhou
- Department of Physiology, The University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA.
| | | | | | - Jian-Xing Ma
- Department of Physiology, The University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA.
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Zhao Y, Wu B, Liu Y, Xu J, Yan Q, Zhang J. Knockdown of dickkopf2 inhibits vascular endothelia growth factor expression through the Wnt/β-catenin signaling pathway in human retinal pigment epithelial cells under hypoxic conditions. Exp Ther Med 2018; 15:4056-4060. [PMID: 29581753 DOI: 10.3892/etm.2018.5915] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2015] [Accepted: 02/01/2017] [Indexed: 12/14/2022] Open
Abstract
Hypoxia has been demonstrated to be a proangiogenic factor that induces vascular endothelial growth factor (VEGF) in retinal pigment epithelial (RPE) cells. Dickkopf2 (DKK2), originally known as Wnt antagonist, has recently been demonstrated to have an important regulatory role in angiogenesis; however, the specific role of DKK2 in RPE cells is not known. In the present study, the effects of DKK2 on VEGF expression under hypoxic conditions were investigated, as well as the molecular mechanisms involved. The results demonstrated that the expression of DKK2 was markedly increased under hypoxic conditions compared with normoxic conditions. Knockdown of DKK2 markedly attenuated the CoCl2-induced expression of hypoxia-inducible factor (HIF)-1α and VEGF in RPE cells. Furthermore, knockdown of DKK2 markedly inhibited the expression of β-catenin induced by hypoxia. In conclusion, the findings of the present study demonstrate that knockdown of DKK2 inhibits the hypoxia-induced production of VEGF by suppressing the activation of the Wnt/β-catenin signaling pathway.
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Affiliation(s)
- Yu Zhao
- Department of Ophthalmology, The Fourth Affiliated Hospital of China Medical University, Shenyang, Liaoning 110005, P.R. China
| | - Bin Wu
- Department of Ophthalmology, The Fourth Affiliated Hospital of China Medical University, Shenyang, Liaoning 110005, P.R. China
| | - Ye Liu
- Department of Ophthalmology, The Fourth Affiliated Hospital of China Medical University, Shenyang, Liaoning 110005, P.R. China
| | - Jun Xu
- Department of Ophthalmology, The Fourth Affiliated Hospital of China Medical University, Shenyang, Liaoning 110005, P.R. China
| | - Qichang Yan
- Department of Ophthalmology, The Fourth Affiliated Hospital of China Medical University, Shenyang, Liaoning 110005, P.R. China
| | - Jinsong Zhang
- Department of Ophthalmology, The Fourth Affiliated Hospital of China Medical University, Shenyang, Liaoning 110005, P.R. China
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Feng Y, Wang J, Yuan Y, Zhang X, Shen M, Yuan F. miR-539-5p inhibits experimental choroidal neovascularization by targeting CXCR7. FASEB J 2018; 32:1626-1639. [PMID: 29146732 DOI: 10.1096/fj.201700640r] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Stromal cell-derived factor-1 (SDF-1) has been previously confirmed to participate in the formation of choroidal neovascularization (CNV) via its receptor, CXC chemokine receptor (CXCR) 4; CXCR7 is a recently identified receptor for SDF-1. The molecular mechanisms and therapeutic value of CXCR7 in CNV remain undefined. In this study, experimental CNV was induced by laser photocoagulation in Brown-Norway pigmented rats, and aberrant CXCR7 overexpression was detected in the retinal pigment epithelial/choroid/sclera tissues of laser-injured eyes. Blockade of CXCR7 activation via CXCR7 knockdown or neutralizing Ab administration inhibited SDF-1-induced cell survival and the tubular formation of human retinal microvascular endothelial cells (HRMECs) in vitro and reduced CNV leakage and lesion size in vivo. By using microRNA array screening and bioinformatic analyses, we identified miR-539-5p as a regulator of CXCR7. Transfection of HRMECs and choroid-retinal endothelial (RF/6A) cells with the miR-539-5p mimic inhibited their survival and tube formation, whereas CXCR7 overexpression rescued the suppressive effect of miR-539-5p. The antiangiogenic activities of the miR-539-5p mimic were additionally demonstrated in vivo by intravitreal injection. ERK1/2 and AKT signaling downstream of CXCR7 is involved in the miR-539-5p regulation of endothelial cell behaviors. These findings suggest that the manipulation of miR-539-5p/CXCR7 levels may have important therapeutic implications in CNV-associated diseases.-Feng, Y., Wang, J., Yuan, Y., Zhang, X., Shen, M., Yuan, F. miR-539-5p inhibits experimental choroidal neovascularization by targeting CXCR7.
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Affiliation(s)
- Yifan Feng
- Department of Ophthalmology, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Jing Wang
- Department of Ophthalmology, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Yuanzhi Yuan
- Department of Ophthalmology, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Xi Zhang
- Department of Ophthalmology, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Minqian Shen
- Department of Ophthalmology, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Fei Yuan
- Department of Ophthalmology, Zhongshan Hospital, Fudan University, Shanghai, China
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Zhang YK, Li JM, Qin L. Suppression of corneal neovascularization by curcumin via inhibition of Wnt/β-catenin pathway activation. Int J Ophthalmol 2017; 10:1791-1797. [PMID: 29259894 DOI: 10.18240/ijo.2017.12.01] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2016] [Accepted: 11/09/2016] [Indexed: 12/22/2022] Open
Abstract
AIM To investigate whether curcumin suppressed corneal neovascularization (CNV) formation via inhibiting activation of Wnt/β-catenin pathway. METHODS Suture-induced CNV was established on Sprague-Dawley (SD) rats. Curcumin were daily administrated by subconjunctival injection. Phosphorylation of low-density lipoprotein receptor-related protein 6 (LRP6) and nuclear accumulation of β-catenin, two indicators of activated Wnt/β-catenin pathway, were determined by Western-blot analysis in subconfluent/proliferating human microvascular endothelial cells (HMEC) and neovascularized corneas. Wnt3a conditioned medium (WCM) were harvested from Wnt3a expressing cells. WCM-induced cell proliferation and endothelial tubular formation capacity was measured by MTT assay and Matrigel assay, respectively. RESULTS Phosphorylation of LRP6 and nuclear accumulation of β-catenin was significantly increased in subconfluent/proliferating endothelial cells. Activation of Wnt/β-catenin pathway by WCM markedly promotes HMEC proliferation and tubular formation. Curcumin inhibited LRP6 phosphorylation and nuclear accumulation of β-catenin. In addition, curcumin attenuated WCM-induced HMEC proliferation and disrupted tubular structure of endothelial cells on Matrigel. Meanwhile curcumin suppressed suture-induced CNV and inhibited LRP6 phosphorylation as well as β-catenin accumulation in SD rats. CONCLUSION Taken together, activation of Wnt/β-catenin pathway could be involved in endothelial proliferation during suture-induced CNV formation and curcumin attenuated CNV formation via inhibition of Wnt/β-catenin pathway activation.
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Affiliation(s)
- Yong-Kang Zhang
- Department of Ophthalmology, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710061, Shaanxi Province, China.,Department of Ophthalmology, Shaanxi Kangfu Hospital, Xi'an 710065, Shaanxi Province, China
| | - Jing-Ming Li
- Department of Ophthalmology, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710061, Shaanxi Province, China
| | - Li Qin
- Department of Ophthalmology, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710061, Shaanxi Province, China
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Qiu F, Matlock G, Chen Q, Zhou K, Du Y, Wang X, Ma JX. Therapeutic Effects of PPARα Agonist on Ocular Neovascularization in Models Recapitulating Neovascular Age-Related Macular Degeneration. Invest Ophthalmol Vis Sci 2017; 58:5065-5075. [PMID: 28980001 PMCID: PMC5633006 DOI: 10.1167/iovs.17-22091] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Purpose This study was designed to evaluate effects of fenofibric acid (Feno-FA), a peroxisome proliferator–activated receptor-alpha (PPARα) agonist, on ocular neovascularization (NV) in models recapitulating neovascular age-related macular degeneration (AMD), and to explore whether the effects are PPARα dependent. Methods Laser-induced choroidal NV (CNV) in rats and very low-density lipoprotein receptor knockout (Vldlr−/−) mice received daily intraperitoneal injections of Feno-FA or vehicle. Vascular leakage was examined by fundus fluorescein angiography and permeability assay using Evans blue as tracer. In CNV rats, severity of CNV was evaluated by CNV areas and CNV volume. In Vldlr−/− mice, subretinal NV (SRNV) and intraretinal NV (IRNV) were quantified in choroid flat mount and retina flat mount, respectively. Inflammatory factors were measured using Western blotting and retinal leukostasis assay. Further, Pparα−/− mice and age-matched wild-type (WT) mice were used for laser-induced CNV and treated with Feno-FA to explore the underlying mechanism. Results Feno-FA significantly reduced vascular leakage in CNV rats and Vldlr−/− mice, reduced CNV volume in laser-induced CNV rats, and suppressed SRNV and IRNV in Vldlr−/− mice. In addition, Feno-FA downregulated the expression of inflammatory factors, including VEGF, TNF-α, and intercellular cell adhesion molecule-1 (ICAM-1), in the eyecups of CNV rats and decreased adherent retinal leukocytes in Vldlr−/− mice. Furthermore, Pparα−/− mice developed more severe CNV compared with WT mice, and PPARα knockout abolished the beneficial effects of Feno-FA on CNV. Conclusions Feno-FA has therapeutic effects on ocular NV in models recapitulating neovascular AMD through a PPARα-dependent mechanism.
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Affiliation(s)
- Fangfang Qiu
- Department of Physiology, The University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States
| | - Greg Matlock
- Department of Physiology, The University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States
| | - Qian Chen
- Department of Physiology, The University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States
| | - Kelu Zhou
- Department of Physiology, The University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States
| | - Yanhong Du
- Department of Physiology, The University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States
| | - Xiang Wang
- Department of Cell Biology, The University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States
| | - Jian-Xing Ma
- Department of Physiology, The University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States
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Vallée A, Lecarpentier Y, Guillevin R, Vallée JN. PPARγ agonists: Potential treatments for exudative age-related macular degeneration. Life Sci 2017; 188:123-130. [PMID: 28887057 DOI: 10.1016/j.lfs.2017.09.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Revised: 08/29/2017] [Accepted: 09/05/2017] [Indexed: 12/22/2022]
Abstract
Choroidal neovascularization (CNV) characterizes the progression of exudative age-related macular degeneration (AMD) with the deterioration in the central vision. Vascular inflammation, and overproduction of inflammatory cytokines, growth factors and aberrant endothelial cell migration, initiate defective blood vessel proliferation in exudative AMD. CNV formation is initiated by the interplay between inflammation, the hallmark of exudative AMD, and the activation of WNT/β-catenin pathway. Upregulation of WNT/β-catenin pathway involves activation of PI3K/Akt pathway and then the Warburg effect to produce lactate. Lactate production generates VEGF expression and then participates to the initiation of CNV in exudative AMD. WNT/β-catenin pathway and PPARγ act in an opposite manner in several diseases. We focus this review on the interplay between PPARγ and canonical WNT/β-catenin pathway and the anti-inflammatory role of PPARγ in exudative AMD. In exudative AMD, PPARγ agonists downregulate inflammation and the WNT/β-catenin pathway. PPARγ agonists can appear as promising treatment against the initiation and the progression of CNV in exudative AMD.
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Affiliation(s)
- Alexandre Vallée
- Experimental and Clinical Neurosciences Laboratory, INSERM U1084, University of Poitiers, Poitiers, France; Laboratoire de Mathématiques et Applications (LMA), UMR CNRS 7348, Université de Poitiers, France.
| | - Yves Lecarpentier
- Centre de Recherche Clinique, Grand Hôpital de l'Est Francilien (GHEF), Meaux, France
| | - Rémy Guillevin
- Université de Poitiers et CHU de Poitiers, DACTIM, Laboratoire de Mathématiques et Applications, UMR CNRS 7348, SP2MI, Futuroscope, France
| | - Jean-Noël Vallée
- Laboratoire de Mathématiques et Applications (LMA), UMR CNRS 7348, Université de Poitiers, France; CHU Amiens Picardie, Université Picardie Jules Verne (UPJV), Amiens, France
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28
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Vallée A, Lecarpentier Y, Guillevin R, Vallée JN. Aerobic Glycolysis Hypothesis Through WNT/Beta-Catenin Pathway in Exudative Age-Related Macular Degeneration. J Mol Neurosci 2017; 62:368-379. [PMID: 28689265 DOI: 10.1007/s12031-017-0947-4] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2017] [Accepted: 06/28/2017] [Indexed: 12/18/2022]
Abstract
Exudative age-related macular degeneration (AMD) is characterized by molecular mechanisms responsible for the initiation of choroidal neovascularization (CNV). Inflammatory processes are associated with upregulation of the canonical WNT/beta-catenin pathway in exudative AMD. We focus this review on the link between WNT/beta-catenin pathway activation and neovascular progression in exudative AMD through activation of aerobic glycolysis for production of angiogenic factors. Increased WNT/beta-catenin pathway involves hexokinase 2 (HK2) and pyruvate kinase M2 (PKM2). WNT/beta-catenin pathway stimulates PI3K/Akt pathway and then HIF-1alpha which activates glycolytic enzymes: glucose transporter (Glut), pyruvate dehydrogenase kinase 1 (PDK1), lactate dehydrogenase A (LDH-A), and monocarboxylate lactate transporter (MCT-1). This phenomenon is called aerobic glycolysis or the Warburg effect. Consequently, phosphorylation of PDK-1 inhibits the pyruvate dehydrogenase complex (PDH). Thus, a large part of pyruvate cannot be converted into acetyl-CoA in mitochondria and only a part of acetyl-CoA can enter the tricarboxylic acid cycle. Cytosolic pyruvate is converted into lactate through the action of LDH-A. In exudative AMD, high level of cytosolic lactate is correlated with increase of VEGF expression, the angiogenic factor of CNV. Photoreceptors in retina cells can metabolize glucose through aerobic glycolysis to protect them against oxidative damage, as cancer cells do.
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Affiliation(s)
- Alexandre Vallée
- Experimental and Clinical Neurosciences Laboratory, INSERM U1084, University of Poitiers, Poitiers, France.
- Laboratoire de Mathématiques et Applications (LMA), UMR CNRS 7348, Université de Poitiers, 11 Boulevard Marie et Pierre Curie, Poitiers, France.
| | | | - Rémy Guillevin
- DACTIM, Laboratoire de Mathématiques et Applications, Université de Poitiers et CHU de Poitiers, UMR CNRS 7348, SP2MI Futuroscope, Chasseneuil-du-Poitou, France
| | - Jean-Noël Vallée
- Laboratoire de Mathématiques et Applications (LMA), UMR CNRS 7348, Université de Poitiers, 11 Boulevard Marie et Pierre Curie, Poitiers, France
- CHU Amiens Picardie, Université Picardie Jules Verne (UPJV), Amiens, France
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29
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Chen Q, Ma JX. Canonical Wnt signaling in diabetic retinopathy. Vision Res 2017; 139:47-58. [PMID: 28545982 DOI: 10.1016/j.visres.2017.02.007] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2017] [Revised: 02/21/2017] [Accepted: 02/22/2017] [Indexed: 11/16/2022]
Abstract
Diabetic retinopathy (DR) is a common eye complication of diabetes, and the pathogenic mechanism of DR is still under investigation. The canonical Wnt signaling pathway is an evolutionarily conserved pathway that plays fundamental roles in embryogenesis and adult tissue homeostasis. Wnt signaling regulates expression of multiple genes that control retinal development and eye organogenesis, and dysregulated Wnt signaling plays pathophysiological roles in many ocular diseases, including DR. This review highlights recent progress in studies of Wnt signaling in DR. We discuss Wnt signaling regulation in the retina and dysregulation of Wnt signaling associated with ocular diseases with an emphasis on DR. We also discuss the therapeutic potential of modulating Wnt signaling in DR. Continued studies in this field will advance our current understanding on DR and contribute to the development of new treatments.
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Affiliation(s)
- Qian Chen
- Department of Physiology, Harold Hamm Diabetes Center, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, United States
| | - Jian-Xing Ma
- Department of Physiology, Harold Hamm Diabetes Center, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, United States.
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30
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Qiu F, Liu Z, Zhou Y, He J, Gong S, Bai X, Zeng Y, Liu Z, Ma JX. Decreased Circulating Levels of Dickkopf-1 in Patients with Exudative Age-related Macular Degeneration. Sci Rep 2017; 7:1263. [PMID: 28455497 PMCID: PMC5430640 DOI: 10.1038/s41598-017-01119-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Accepted: 03/22/2017] [Indexed: 02/07/2023] Open
Abstract
Aberrant activation of the Wnt/β-catenin signaling pathway plays a pathogenic role in retinal inflammation and neovascularization. Here, we investigated whether circulating levels of Dickkopf-1 (DKK-1), a specific inhibitor of this pathway, are altered in patients with exudative age-related macular degeneration (AMD). Plasma was obtained from 128 patients with exudative AMD, 46 patients with atrophic AMD and 111 healthy controls. DKK-1 levels in plasma were measured using ELISA, and data analyzed with one-way ANOVA, logistic regression analysis and receiver-operating characteristic analysis (ROC). We found that DKK-1 levels were decreased in exudative AMD patients, compared with healthy controls (P < 0.001) and atrophic AMD patients (P < 0.001). The decrease was more prominent in patients with classic choroidal neovascularization (CNV) than those with occult CNV (P < 0.001). The odds ratio (OR) of exudative AMD was 11.71 (95% CI; 5.24–6.13) for lowest versus upper quartile of DKK-1 levels. For discriminating exudative AMD patients, the optimum diagnostic cutoff of DKK-1 was 583.1 pg/mL with the area under curve (AUC) 0.76 (95% CI, 0.70–0.82; P < 0.001), sensitivity 78.1% and specificity 63.1%. These findings suggested that decreased circulating DKK-1 levels are associated with the development and severity of exudative AMD, and have potential to become a biomarker for exudative AMD.
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Affiliation(s)
- Fangfang Qiu
- Eye Institute of Xiamen University, Fujian Province Key Laboratory of Ophthalmology and Visual Science, 4th Floor, Chengyi Building, Xiang'an Campus of Xiamen University, Xiang'an South Road, Xiamen, Fujian, 361102, China.,Department of Physiology, The University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, 73104, United States of America
| | - Zhen Liu
- Eye Institute of Xiamen University, Fujian Province Key Laboratory of Ophthalmology and Visual Science, 4th Floor, Chengyi Building, Xiang'an Campus of Xiamen University, Xiang'an South Road, Xiamen, Fujian, 361102, China
| | - Yueping Zhou
- Eye Institute of Xiamen University, Fujian Province Key Laboratory of Ophthalmology and Visual Science, 4th Floor, Chengyi Building, Xiang'an Campus of Xiamen University, Xiang'an South Road, Xiamen, Fujian, 361102, China
| | - Jia He
- Eye Institute of Xiamen University, Fujian Province Key Laboratory of Ophthalmology and Visual Science, 4th Floor, Chengyi Building, Xiang'an Campus of Xiamen University, Xiang'an South Road, Xiamen, Fujian, 361102, China
| | - Songjian Gong
- Affiliated Xiamen Eye Center of Xiamen University, Xiamen, Fujian, China
| | - Xue Bai
- Affiliated Xiamen Eye Center of Xiamen University, Xiamen, Fujian, China.,Department of Ophthalmology, Affiliated Zhongshan Hospital of Xiamen University, Xiamen, Fujian, China
| | - Yingxia Zeng
- Affiliated Xiamen Eye Center of Xiamen University, Xiamen, Fujian, China
| | - Zuguo Liu
- Eye Institute of Xiamen University, Fujian Province Key Laboratory of Ophthalmology and Visual Science, 4th Floor, Chengyi Building, Xiang'an Campus of Xiamen University, Xiang'an South Road, Xiamen, Fujian, 361102, China. .,Department of Physiology, The University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, 73104, United States of America.
| | - Jian-Xing Ma
- Department of Physiology, The University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, 73104, United States of America.
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Abstract
A recent advancement in the treatment of burn scars has been the use of the carbon dioxide (CO2) laser to perform fractional photothermolysis. In this analysis, we describe our results and patient-reported outcomes with the use of fractional CO2 laser for the treatment of burn-related scarring. We performed a retrospective study of all patients who underwent CO2 laser procedures for treatment of symptomatic burn scars and skin grafts at one accredited regional burn center. Burn injury and laser treatment demographics, as well as complications, are reported. A questionnaire was administered to all patients and included patient-reported outcome measures aimed at understanding the patient experience and their subjective response to treatment. A total of 387 CO2 laser procedures were performed on 131 patients for the treatment of symptomatic burn scars and skin grafts between October 1, 2011, and May 1, 2014 (average, 2.95 procedures/patient; range, 1-11). Average time between injury and first laser was 597.35 days (range, 60-13,475). Average time between laser treatments (when multiple) was 117.73 days (range, 22-514). There were no infections requiring treatment with oral antibiotics. Overall patient satisfaction with laser therapy was 96.7%. Patients reported reductions in neuropathic pain, tightness (contracture), and pruritus (54.0, 50.6, and 49.0%, respectively). Fractional photothermolysis utilizing the CO2 laser is a safe and effective modality for the treatment of symptomatic burn scars, donor sites, and skin grafts. Patient satisfaction with this procedure is high, and complications are low. Significant improvements in scar appearance, pliability, tightness, neuropathic pain, and pruritus were commonly reported.
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Wang Y, Sang A, Zhu M, Zhang G, Guan H, Ji M, Chen H. Tissue factor induces VEGF expression via activation of the Wnt/β-catenin signaling pathway in ARPE-19 cells. Mol Vis 2016; 22:886-97. [PMID: 27499609 PMCID: PMC4961466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2016] [Accepted: 07/22/2016] [Indexed: 10/24/2022] Open
Abstract
PURPOSE The purpose of the present study was to investigate the potential signal mechanism of tissue factor (TF) in the regulation of the expression of vascular endothelial growth factor (VEGF) in human retinal pigment epithelial (ARPE-19) cells. METHODS An in vitro RPE cell chemical hypoxia model was established by adding cobalt chloride (CoCl2) in the culture medium. The irritative concentration of CoCl2 was determined with a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay kit. VEGF production in ARPE-19 cells was measured with enzyme-linked immunosorbent assay (ELISA) and western blotting. The Wnt signaling pathway-associated molecules, including phospho-glycogen synthase kinase 3β (p-GSK3β), GSK3β, p-β-catenin and β-catenin, were detected with western blotting. pEGFP-N3-hTF was constructed and verified with digestion of the restriction enzyme and sequencing analysis. Human TF overexpression and silencing plasmids were transfected into the ARPE-19 cells to clarify the causal relationship between TF and VEGF expression. The Transwell coculture system of ARPE-19 cells and RF/6A rhesus macaque choroid-retinal endothelial cells was performed to evaluate cell invasion and tube formation ability. RESULTS Our anoxic model of ARPE-19 cells showed that TF expression was upregulated in accordance with variations in hypoxia-inducible factor 1-alpha (HIF-1α) and VEGF levels. Silencing and overexpression of TF decreased and increased VEGF expression, respectively. The Wnt/β-catenin signaling pathway played an important role in this effect. Results from the ARPE-19 cell and RF/6A cell coculture system showed that the enhancement of TF expression in the ARPE-19 cells led to significantly faster invasion and stronger tube-forming ability of the RF/6A cells, while siRNA-mediated TF silencing caused the opposite effects. Pharmacological disruption of Wnt signaling IWR-1-endo inhibited the effects compared to the TF-overexpressing group, indicating the importance of the Wnt/β-catenin signaling pathway in the process of TF-induced VEGF expression and angiogenesis. CONCLUSIONS Involvement of the activation of the Wnt/β-catenin signaling pathway is an important mediator for TF-induced VEGF production during the process of angiogenesis. Thus, our findings may ascertain the molecular regulation of TF in neovessel formation and show significant therapeutic implications.
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Kim JH, Park S, Chung H, Oh S. Wnt5a attenuates the pathogenic effects of the Wnt/β-catenin pathway in human retinal pigment epithelial cells via down-regulating β-catenin and Snail. BMB Rep 2016; 48:525-30. [PMID: 26246285 PMCID: PMC4641237 DOI: 10.5483/bmbrep.2015.48.9.140] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2015] [Indexed: 12/19/2022] Open
Abstract
Activation of the Wnt/β-catenin pathway plays a pathogenic role in age-related macular degeneration (AMD) and is thus a potential target for the development of therapeutics for this disease. Here, we demonstrated that Wnt5a antagonized β-catenin response transcription (CRT) induced with Wnt3a by promoting β-catenin phosphorylation at Ser33/Ser37/Thr41 and its subsequent degradation in human retinal pigment epithelial (RPE) cells. Wnt5a decreased the levels of vascular endothelial growth factor (VEGF), tumor necrosis factor-α(TNF-α), and nuclear factor-κB (NF-κB), which was up-regulated by Wnt3a. Furthermore, Wnt5a increased E-cadherin expression and decreased cell migration by down-regulating Snail expression, thereby abrogating the Wnt3a-induced epithelial-mesenchymal transition (EMT) in human RPE cells. Our findings suggest that Wnt5a suppresses the pathogenic effects of canonical Wnt signaling in human RPE cells by promoting β-catenin phosphorylation and degradation. Therefore, Wnt5a has significant therapeutic potential for the treatment of AMD. [BMB Reports 2015; 48(9): 525-530]
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Affiliation(s)
- Joo-Hyun Kim
- Department of Bio and Fermentation Convergence Technology, Kookmin University, Seoul 02707, Korea
| | - Seoyoung Park
- Department of Bio and Fermentation Convergence Technology, Kookmin University, Seoul 02707, Korea
| | - Hyewon Chung
- Department of Opthalmology, Konkuk University School of Medicine, Seoul 05066, Korea
| | - Sangtaek Oh
- Department of Bio and Fermentation Convergence Technology, Kookmin University, Seoul 02707, Korea
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Wang H, Hartnett ME. Regulation of signaling events involved in the pathophysiology of neovascular AMD. Mol Vis 2016; 22:189-202. [PMID: 27013848 PMCID: PMC4789180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Accepted: 02/25/2016] [Indexed: 11/04/2022] Open
Abstract
Neovascular age-related macular degeneration (AMD) is a complex disease in which an individual's genetic predisposition is affected by aging and environmental stresses, which trigger signaling pathways involving inflammation, oxidation, and/or angiogenesis in the RPE cells and choroidal endothelial cells (CECs), to lead to vision loss from choroidal neovascularization. Antiangiogenic therapies have greatly improved clinical outcomes in the last decade; however, vision improves in less than half of patients treated for neovascular AMD, and treatments remain inadequate for atrophic AMD. Many studies focus on genetic predisposition or the association of outcomes in trials of human neovascular AMD but are unable to evaluate the effects between different cell types involved in AMD and the signaling events that take place to cause pathologic biologic events. This manuscript complements other reviews in that it describes what is known generally in human AMD studies and clinical trials testing methods to inhibit vascular endothelial growth factor (VEGF inhibitors) and presents pathologic signaling events that develop in two important cell types, the RPE cells and the CECs, when stimulated by stresses or placed into conditions similar to what is currently understood to occur in neovascular AMD. This manuscript complements other reviews by discussing signaling events that are activated by cell-cell or cell-matrix interactions. These considerations are particularly important when considering growth factors, such as VEGF, which are important in physiologic and pathologic processes, or GTPases that are present but active only if GTP bound. In either case, it is essential to understand the role of signaling activation to distinguish what is pathologic from what is physiologic. Particularly important is the essential role of activated Rac1 in CEC transmigration of the RPE monolayer, an important step in blindness associated with neovascular AMD. Other concepts discussed include the importance of feed-forward loops that overwhelm mechanisms that seek to restore homeostasis in cells and the importance of regulating, instead of abolishing, signaling events in a chronic, complex disease, such as neovascular AMD. These concepts are important as we move to the next stages in developing treatments for neovascular AMD. A novel therapeutic strategy that will be discussed is activating an isoform of the GTPase, Rap1, which can regulate downstream signaling and a pathologic feed-forward loop leading to Rac1 activation and migration of CECs.
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Tuo J, Wang Y, Cheng R, Li Y, Chen M, Qiu F, Qian H, Shen D, Penalva R, Xu H, Ma JX, Chan CC. Wnt signaling in age-related macular degeneration: human macular tissue and mouse model. J Transl Med 2015; 13:330. [PMID: 26476672 PMCID: PMC4609061 DOI: 10.1186/s12967-015-0683-x] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Accepted: 09/29/2015] [Indexed: 01/02/2023] Open
Abstract
Background The wingless-type MMTV integration site (Wnt) signaling is a group of signal transduction pathways. In canonical Wnt pathway, Wnt ligands bind to low-density lipoprotein receptor-related protein 5 or 6 (LRP5 or LRP6), resulting in phosphorylation and activation of the receptor. We hypothesize that canonical Wnt pathway plays a role in the retinal lesion of age-related macular degeneration (AMD), a leading cause of irreversible central visual loss in elderly. Methods We examined LRP6 phosphorylation and Wnt signaling cascade in human retinal sections and plasma kallistatin, an endogenous inhibitor of the Wnt pathway in AMD patients and non-AMD subjects. We also used the Ccl2−/−/Cx3cr1−/−/rd8 and Ccl2−/−/Cx3cr1gfp/gfp mouse models with AMD-like retinal degeneration to further explore the involvement of Wnt signaling activation in the retinal lesions in those models and to preclinically evaluate the role of Wnt signaling suppression as a potential therapeutic option for AMD. Results We found higher levels of LRP6 (a key Wnt signaling receptor) protein phosphorylation and transcripts of the Wnt pathway-targeted genes, as well as higher beta-catenin protein in AMD macula compared to controls. Kallistatin was decreased in the plasma of AMD patients. Retinal non-phosphorylated-β-catenin and phosphorylated-LRP6 were higher in Ccl2−/−/Cx3cr1−/−/rd8 mice than that in wild type. Intravitreal administration of an anti-LRP6 antibody slowed the progression of retinal lesions in Ccl2−/−/Cx3cr1−/−/rd8 and Ccl2−/−/Cx3cr1gfp/gfp mice. Electroretinography of treated eyes exhibited larger amplitudes compared to controls in both mouse models. A2E, a retinoid byproduct associated with AMD was lower in the treated eyes of Ccl2−/−/Cx3cr1−/−/rd8 mice. Anti-LRP6 also suppressed the expression of Tnf-α and Icam-1 in Ccl2−/−/Cx3cr1−/−/rd8 retinas. Conclusions Wnt signaling may be disturbed in AMD patients, which could contribute to the retinal inflammation and increased A2E levels found in AMD. Aberrant activation of canonical Wnt signaling might also contribute to the focal retinal degenerative lesions of mouse models with Ccl2 and Cx3cr1 deficiency, and intravitreal administration of anti-LRP6 antibody could be beneficial by deactivating the canonical Wnt pathway. Electronic supplementary material The online version of this article (doi:10.1186/s12967-015-0683-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Jingsheng Tuo
- Laboratory of Immunology, National Eye Institute, National Institutes of Health, 10 Center Drive, Bldg. 10, Rm. 10N103, NIH/NEI, Bethesda, MD, 20892-1857, USA.
| | - Yujuan Wang
- Laboratory of Immunology, National Eye Institute, National Institutes of Health, 10 Center Drive, Bldg. 10, Rm. 10N103, NIH/NEI, Bethesda, MD, 20892-1857, USA.
| | - Rui Cheng
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA.
| | - Yichao Li
- Visual Function Core, National Eye Institute, National Institutes of Health, Bethesda, MD, USA.
| | - Mei Chen
- Centre for Experimental Medicine, Queen's University Belfast, Belfast, UK.
| | - Fangfang Qiu
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA.
| | - Haohua Qian
- Visual Function Core, National Eye Institute, National Institutes of Health, Bethesda, MD, USA.
| | - Defen Shen
- Laboratory of Immunology, National Eye Institute, National Institutes of Health, 10 Center Drive, Bldg. 10, Rm. 10N103, NIH/NEI, Bethesda, MD, 20892-1857, USA.
| | - Rosana Penalva
- Centre for Experimental Medicine, Queen's University Belfast, Belfast, UK.
| | - Heping Xu
- Centre for Experimental Medicine, Queen's University Belfast, Belfast, UK.
| | - Jian-Xing Ma
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA.
| | - Chi-Chao Chan
- Laboratory of Immunology, National Eye Institute, National Institutes of Health, 10 Center Drive, Bldg. 10, Rm. 10N103, NIH/NEI, Bethesda, MD, 20892-1857, USA.
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Endothelial microRNA-150 is an intrinsic suppressor of pathologic ocular neovascularization. Proc Natl Acad Sci U S A 2015; 112:12163-8. [PMID: 26374840 DOI: 10.1073/pnas.1508426112] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Pathologic ocular neovascularization commonly causes blindness. It is critical to identify the factors altered in pathologically proliferating versus normally quiescent vessels to develop effective targeted therapeutics. MicroRNAs regulate both physiological and pathological angiogenesis through modulating expression of gene targets at the posttranscriptional level. However, it is not completely understood if specific microRNAs are altered in pathologic ocular blood vessels, influencing vascular eye diseases. Here we investigated the potential role of a specific microRNA, miR-150, in regulating ocular neovascularization. We found that miR-150 was highly expressed in normal quiescent retinal blood vessels and significantly suppressed in pathologic neovessels in a mouse model of oxygen-induced proliferative retinopathy. MiR-150 substantially decreased endothelial cell function including cell proliferation, migration, and tubular formation and specifically suppressed the expression of multiple angiogenic regulators, CXCR4, DLL4, and FZD4, in endothelial cells. Intravitreal injection of miR-150 mimic significantly decreased pathologic retinal neovascularization in vivo in both wild-type and miR-150 knockout mice. Loss of miR-150 significantly promoted angiogenesis in aortic rings and choroidal explants ex vivo and laser-induced choroidal neovascularization in vivo. In conclusion, miR-150 is specifically enriched in quiescent normal vessels and functions as an endothelium-specific endogenous inhibitor of pathologic ocular neovascularization.
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PEDF and its roles in physiological and pathological conditions: implication in diabetic and hypoxia-induced angiogenic diseases. Clin Sci (Lond) 2015; 128:805-23. [PMID: 25881671 PMCID: PMC4557399 DOI: 10.1042/cs20130463] [Citation(s) in RCA: 102] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Pigment epithelium-derived factor (PEDF) is a broadly expressed multifunctional member of the serine proteinase inhibitor (serpin) family. This widely studied protein plays critical roles in many physiological and pathophysiological processes, including neuroprotection, angiogenesis, fibrogenesis and inflammation. The present review summarizes the temporal and spatial distribution patterns of PEDF in a variety of developing and adult organs, and discusses its functions in maintaining physiological homoeostasis. The major focus of the present review is to discuss the implication of PEDF in diabetic and hypoxia-induced angiogenesis, and the pathways mediating PEDF's effects under these conditions. Furthermore, the regulatory mechanisms of PEDF expression, function and degradation are also reviewed. Finally, the therapeutic potential of PEDF as an anti-angiogenic drug is briefly summarized.
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Wigg JP, Zhang H, Yang D. A Quantitative and Standardized Method for the Evaluation of Choroidal Neovascularization Using MICRON III Fluorescein Angiograms in Rats. PLoS One 2015; 10:e0128418. [PMID: 26024231 PMCID: PMC4449229 DOI: 10.1371/journal.pone.0128418] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2015] [Accepted: 04/27/2015] [Indexed: 01/18/2023] Open
Abstract
Introduction In-vivo imaging of choroidal neovascularization (CNV) has been increasingly recognized as a valuable tool in the investigation of age-related macular degeneration (AMD) in both clinical and basic research applications. Arguably the most widely utilised model replicating AMD is laser generated CNV by rupture of Bruch’s membrane in rodents. Heretofore CNV evaluation via in-vivo imaging techniques has been hamstrung by a lack of appropriate rodent fundus camera and a non-standardised analysis method. The aim of this study was to establish a simple, quantifiable method of fluorescein fundus angiogram (FFA) image analysis for CNV lesions. Methods Laser was applied to 32 Brown Norway Rats; FFA images were taken using a rodent specific fundus camera (Micron III, Phoenix Laboratories) over 3 weeks and compared to conventional ex-vivo CNV assessment. FFA images acquired with fluorescein administered by intraperitoneal injection and intravenous injection were compared and shown to greatly influence lesion properties. Utilising commonly used software packages, FFA images were assessed for CNV and chorioretinal burns lesion area by manually outlining the maximum border of each lesion and normalising against the optic nerve head. Net fluorescence above background and derived value of area corrected lesion intensity were calculated. Results CNV lesions of rats treated with anti-VEGF antibody were significantly smaller in normalised lesion area (p<0.001) and fluorescent intensity (p<0.001) than the PBS treated control two weeks post laser. The calculated area corrected lesion intensity was significantly smaller (p<0.001) in anti-VEGF treated animals at 2 and 3 weeks post laser. The results obtained using FFA correlated with, and were confirmed by conventional lesion area measurements from isolectin stained choroidal flatmounts, where lesions of anti-VEGF treated rats were significantly smaller at 2 weeks (p = 0.049) and 3 weeks (p<0.001) post laser. Conclusion The presented method of in-vivo FFA quantification of CNV, including acquisition variable corrections, using the Micron III system and common use software establishes a reliable method for detecting and quantifying CNV enabling longitudinal studies and represents an important alternative to conventional CNV quantification methods.
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Affiliation(s)
- Jonathan P. Wigg
- Centre for Eye Research Australia, University of Melbourne, Royal Victorian Eye and Ear Hospital, East Melbourne, Victoria, Australia
| | - Hong Zhang
- Centre for Eye Research Australia, University of Melbourne, Royal Victorian Eye and Ear Hospital, East Melbourne, Victoria, Australia
- Eye Hospital, Harbin Medical University, Nangang District, Harbin, Heilongjiang Province, China
- * E-mail:
| | - Dong Yang
- Centre for Eye Research Australia, University of Melbourne, Royal Victorian Eye and Ear Hospital, East Melbourne, Victoria, Australia
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Huang J, Li YJ, Liu JY, Zhang YY, Li XM, Wang LN, Yao J, Jiang Q, Yan B. Identification of Corneal Neovascularization–Related Long Noncoding RNAs Through Microarray Analysis. Cornea 2015; 34:580-7. [DOI: 10.1097/ico.0000000000000389] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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Wang Z, Cheng R, Lee K, Tyagi P, Ding L, Kompella UB, Chen J, Xu X, Ma JX. Nanoparticle-mediated expression of a Wnt pathway inhibitor ameliorates ocular neovascularization. Arterioscler Thromb Vasc Biol 2015; 35:855-64. [PMID: 25657312 DOI: 10.1161/atvbaha.114.304627] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
OBJECTIVE The deficiency of very low-density lipoprotein receptor resulted in Wnt signaling activation and neovascularization in the retina. The present study sought to determine whether the very low-density lipoprotein receptor extracellular domain (VLN) is responsible for the inhibition of Wnt signaling in ocular tissues. APPROACH AND RESULTS A plasmid expressing the soluble VLN was encapsulated with poly(lactide-co-glycolide acid) to form VLN nanoparticles (VLN-NP). Nanoparticles containing a plasmid expressing the low-density lipoprotein receptor extracellular domain nanoparticle were used as negative control. MTT, modified Boyden chamber, and Matrigel (™) assays were used to evaluate the inhibitory effect of VLN-NP on Wnt3a-stimulated endothelial cell proliferation, migration, and tube formation. Vldlr(-/-) mice, oxygen-induced retinopathy, and alkali burn-induced corneal neovascularization models were used to evaluate the effect of VLN-NP on ocular neovascularization. Wnt reporter mice (BAT-gal), Western blotting, and luciferase assay were used to evaluate Wnt pathway activity. Our results showed that VLN-NP specifically inhibited Wnt3a-induced endothelial cell proliferation, migration, and tube formation. Intravitreal injection of VLN-NP inhibited abnormal neovascularization in Vldlr(-/-), oxygen-induced retinopathy, and alkali burn-induced corneal neovascularization models, compared with low-density lipoprotein receptor extracellular domain nanoparticle. VLN-NP significantly inhibited the phosphorylation of low-density lipoprotein receptor-related protein 6, the accumulation of β-catenin, and the expression of vascular endothelial growth factor in vivo and in vitro. CONCLUSIONS Taken together, these results suggest that the soluble VLN is a negative regulator of the Wnt pathway and has antiangiogenic activities. Nanoparticle-mediated expression of VLN may thus represent a novel therapeutic approach to treat pathological ocular angiogenesis and potentially other vascular diseases affected by Wnt signaling.
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Affiliation(s)
- Zhongxiao Wang
- From the Department of Ophthalmology, Shanghai First People's Hospital Affiliated to Shanghai Jiaotong University, Shanghai, China (Z.W., X.X.); Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City (Z.W., R.C., K.L., L.D., J.-x.M.); Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Denver, Aurora (P.T., U.B.K.); Department of Ophthalmology, Xiangya Hospital, Central South University, Changsha, China (L.D.); and Department of Ophthalmology, Boston Children's Hospital, Harvard Medical School, MA (J.C.)
| | - Rui Cheng
- From the Department of Ophthalmology, Shanghai First People's Hospital Affiliated to Shanghai Jiaotong University, Shanghai, China (Z.W., X.X.); Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City (Z.W., R.C., K.L., L.D., J.-x.M.); Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Denver, Aurora (P.T., U.B.K.); Department of Ophthalmology, Xiangya Hospital, Central South University, Changsha, China (L.D.); and Department of Ophthalmology, Boston Children's Hospital, Harvard Medical School, MA (J.C.)
| | - Kyungwon Lee
- From the Department of Ophthalmology, Shanghai First People's Hospital Affiliated to Shanghai Jiaotong University, Shanghai, China (Z.W., X.X.); Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City (Z.W., R.C., K.L., L.D., J.-x.M.); Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Denver, Aurora (P.T., U.B.K.); Department of Ophthalmology, Xiangya Hospital, Central South University, Changsha, China (L.D.); and Department of Ophthalmology, Boston Children's Hospital, Harvard Medical School, MA (J.C.)
| | - Puneet Tyagi
- From the Department of Ophthalmology, Shanghai First People's Hospital Affiliated to Shanghai Jiaotong University, Shanghai, China (Z.W., X.X.); Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City (Z.W., R.C., K.L., L.D., J.-x.M.); Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Denver, Aurora (P.T., U.B.K.); Department of Ophthalmology, Xiangya Hospital, Central South University, Changsha, China (L.D.); and Department of Ophthalmology, Boston Children's Hospital, Harvard Medical School, MA (J.C.)
| | - Lexi Ding
- From the Department of Ophthalmology, Shanghai First People's Hospital Affiliated to Shanghai Jiaotong University, Shanghai, China (Z.W., X.X.); Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City (Z.W., R.C., K.L., L.D., J.-x.M.); Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Denver, Aurora (P.T., U.B.K.); Department of Ophthalmology, Xiangya Hospital, Central South University, Changsha, China (L.D.); and Department of Ophthalmology, Boston Children's Hospital, Harvard Medical School, MA (J.C.)
| | - Uday B Kompella
- From the Department of Ophthalmology, Shanghai First People's Hospital Affiliated to Shanghai Jiaotong University, Shanghai, China (Z.W., X.X.); Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City (Z.W., R.C., K.L., L.D., J.-x.M.); Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Denver, Aurora (P.T., U.B.K.); Department of Ophthalmology, Xiangya Hospital, Central South University, Changsha, China (L.D.); and Department of Ophthalmology, Boston Children's Hospital, Harvard Medical School, MA (J.C.)
| | - Jing Chen
- From the Department of Ophthalmology, Shanghai First People's Hospital Affiliated to Shanghai Jiaotong University, Shanghai, China (Z.W., X.X.); Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City (Z.W., R.C., K.L., L.D., J.-x.M.); Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Denver, Aurora (P.T., U.B.K.); Department of Ophthalmology, Xiangya Hospital, Central South University, Changsha, China (L.D.); and Department of Ophthalmology, Boston Children's Hospital, Harvard Medical School, MA (J.C.)
| | - Xun Xu
- From the Department of Ophthalmology, Shanghai First People's Hospital Affiliated to Shanghai Jiaotong University, Shanghai, China (Z.W., X.X.); Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City (Z.W., R.C., K.L., L.D., J.-x.M.); Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Denver, Aurora (P.T., U.B.K.); Department of Ophthalmology, Xiangya Hospital, Central South University, Changsha, China (L.D.); and Department of Ophthalmology, Boston Children's Hospital, Harvard Medical School, MA (J.C.).
| | - Jian-Xing Ma
- From the Department of Ophthalmology, Shanghai First People's Hospital Affiliated to Shanghai Jiaotong University, Shanghai, China (Z.W., X.X.); Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City (Z.W., R.C., K.L., L.D., J.-x.M.); Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Denver, Aurora (P.T., U.B.K.); Department of Ophthalmology, Xiangya Hospital, Central South University, Changsha, China (L.D.); and Department of Ophthalmology, Boston Children's Hospital, Harvard Medical School, MA (J.C.).
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Korbolina EE, Ershov NI, Bryzgalov LO, Kolosova NG. Application of quantitative trait locus mapping and transcriptomics to studies of the senescence-accelerated phenotype in rats. BMC Genomics 2014; 15 Suppl 12:S3. [PMID: 25563673 PMCID: PMC4303943 DOI: 10.1186/1471-2164-15-s12-s3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Background Etiology of complex disorders, such as cataract and neurodegenerative diseases including age-related macular degeneration (AMD), remains poorly understood due to the paucity of animal models, fully replicating the human disease. Previously, two quantitative trait loci (QTLs) associated with early cataract, AMD-like retinopathy, and some behavioral aberrations in senescence-accelerated OXYS rats were uncovered on chromosome 1 in a cross between OXYS and WAG rats. To confirm the findings, we generated interval-specific congenic strains, WAG/OXYS-1.1 and WAG/OXYS-1.2, carrying OXYS-derived loci of chromosome 1 in the WAG strain. Both congenic strains displayed early cataract and retinopathy but differed clinically from OXYS rats. Here we applied a high-throughput RNA sequencing (RNA-Seq) strategy to facilitate nomination of the candidate genes and functional pathways that may be responsible for these differences and can contribute to the development of the senescence-accelerated phenotype of OXYS rats. Results First, the size and map position of QTL-derived congenic segments were determined by comparative analysis of coding single-nucleotide polymorphisms (SNPs), which were identified for OXYS, WAG, and congenic retinal RNAs after sequencing. The transferred locus was not what we expected in WAG/OXYS-1.1 rats. In rat retina, 15442 genes were expressed. Coherent sets of differentially expressed genes were identified when we compared RNA-Seq retinal profiles of 20-day-old WAG/OXYS-1.1, WAG/OXYS-1.2, and OXYS rats. The genes most different in the average expression level between the congenic strains included those generally associated with the Wnt, integrin, and TGF-β signaling pathways, widely involved in neurodegenerative processes. Several candidate genes (including Arhgap33, Cebpg, Gtf3c1, Snurf, Tnfaip3, Yme1l1, Cbs, Car9 and Fn1) were found to be either polymorphic in the congenic loci or differentially expressed between the strains. These genes may contribute to the development of cataract and retinopathy. Conclusions This study is the first RNA-Seq analysis of the rat retinal transcriptome generated with 40 mln sequencing read depth. The integration of QTL and transcriptomic analyses in our study forms the basis of future research into the relationship between the candidate genes within the congenic regions and specific changes in the retinal transcriptome as possible causal mechanisms that underlie age-associated disorders.
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Patel AK, Surapaneni K, Yi H, Nakamura REI, Karli SZ, Syeda S, Lee T, Hackam AS. Activation of Wnt/β-catenin signaling in Muller glia protects photoreceptors in a mouse model of inherited retinal degeneration. Neuropharmacology 2014; 91:1-12. [PMID: 25486619 DOI: 10.1016/j.neuropharm.2014.11.015] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2014] [Revised: 11/13/2014] [Accepted: 11/19/2014] [Indexed: 11/18/2022]
Abstract
The canonical Wnt/β-catenin ("Wnt") pathway is an essential signaling cascade in the embryonic central nervous system (CNS) that regulates neuronal differentiation and survival. Loss of Wnt signaling in developing and adult tissue has been implicated in numerous CNS diseases, but the precise role of Wnt in regulating neuronal survival, and how its absence could lead to disease, is not understood. In this study, we investigated the effect of Wnt activation on neuronal survival in the adult retina, and identified cellular and molecular mediators. Pan-retinal Wnt signaling activation using Wnt3a induced functional and morphological rescue of photoreceptor neurons in the rd10 mouse model of retinal degeneration. Furthermore, Wnt activation using constitutively active β-catenin specifically targeted to Muller glia increased photoreceptor survival and reduced markers of glial and neuronal remodeling. Wnt-induced photoreceptor protection was associated with elevated levels of the prosurvival protein Stat3, and was reduced by shRNA-mediated knock-down of Stat3, indicating cross-talk between survival pathways. Therefore, these data increase our understanding of the role of Wnt signaling in the retina, and identify radial Muller glia as important cellular mediators of Wnt activity.
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Affiliation(s)
- Amit K Patel
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, USA
| | - Krishna Surapaneni
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, USA
| | - Hyun Yi
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, USA
| | - Rei E I Nakamura
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, USA
| | - Sapir Z Karli
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, USA
| | - Sarah Syeda
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, USA
| | - Tinthu Lee
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, USA
| | - Abigail S Hackam
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, USA.
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Zhou KK, Benyajati S, Le Y, Cheng R, Zhang W, Ma JX. Interruption of Wnt signaling in Müller cells ameliorates ischemia-induced retinal neovascularization. PLoS One 2014; 9:e108454. [PMID: 25271989 PMCID: PMC4182699 DOI: 10.1371/journal.pone.0108454] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2014] [Accepted: 08/29/2014] [Indexed: 01/26/2023] Open
Abstract
Retinal Müller cells are major producers of inflammatory and angiogenic cytokines which contribute to diabetic retinopathy (DR). Over-activation of the Wnt/β-catenin pathway has been shown to play an important pathogenic role in DR. However, the roles of Müller cell-derived Wnt/β-catenin signaling in retinal neovascularization (NV) and DR remain undefined. In the present study, mice with conditional β-catenin knockout (KO) in Müller cells were generated and subjected to oxygen-induced retinopathy (OIR) and streptozotocin (STZ)-induced diabetes. Wnt signaling was evaluated by measuring levels of β-catenin and expression of its target genes using immunoblotting. Retinal vascular permeability was measured using Evans blue as a tracer. Retinal NV was visualized by angiography and quantified by counting pre-retinal nuclei. Retinal pericyte loss was evaluated using retinal trypsin digestion. Electroretinography was performed to examine visual function. No abnormalities were detected in the β-catenin KO mice under normal conditions. In OIR, retinal levels of β-catenin and VEGF were significantly lower in the β-catenin KO mice than in littermate controls. The KO mice also had decreased retinal NV and vascular leakage in the OIR model. In the STZ-induced diabetic model, disruption of β-catenin in Müller cells attenuated over-expression of inflammatory cytokines and ameliorated pericyte dropout in the retina. These findings suggest that Wnt signaling activation in Müller cells contributes to retinal NV, vascular leakage and inflammation and represents a potential therapeutic target for DR.
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Affiliation(s)
- Kelu Kevin Zhou
- Department of Physiology, Harold Hamm Diabetes Center, the University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States of America
| | - Siribhinya Benyajati
- Department of Physiology, Harold Hamm Diabetes Center, the University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States of America
| | - Yun Le
- Department of Medicine Endocrinology, Harold Hamm Diabetes Center, the University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States of America
| | - Rui Cheng
- Department of Physiology, Harold Hamm Diabetes Center, the University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States of America
| | - Wenbo Zhang
- Department of Ophthalmology and Visual Sciences, the University of Texas Medical Branch, Galveston, Texas, United States of America
| | - Jian-xing Ma
- Department of Physiology, Harold Hamm Diabetes Center, the University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States of America
- * E-mail:
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Pathogenic role of diabetes-induced PPAR-α down-regulation in microvascular dysfunction. Proc Natl Acad Sci U S A 2013; 110:15401-6. [PMID: 24003152 DOI: 10.1073/pnas.1307211110] [Citation(s) in RCA: 112] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Two independent clinical studies have reported that fenofibrate, a peroxisome proliferator-activated receptor α (PPARα) agonist, has robust therapeutic effects on microvascular complications of diabetes, including diabetic retinopathy (DR) in type 2 diabetic patients. However, the expression and function of PPARα in the retina are unclear. Here, we demonstrated that PPARα is expressed in multiple cell types in the retina. In both type 1 and type 2 diabetes models, expression of PPARα, but not PPARβ/δ or PPARγ, was significantly down-regulated in the retina. Furthermore, high-glucose medium was sufficient to down-regulate PPARα expression in cultured retinal cells. To further investigate the role of PPARα in DR, diabetes was induced in PPARα knockout (KO) mice and wild-type (WT) mice. Diabetic PPARα KO mice developed more severe DR, as shown by retinal vascular leakage, leukostasis, pericyte loss, capillary degeneration, and over-expression of inflammatory factors, compared with diabetic WT mice. In addition, overexpression of PPARα in the retina of diabetic rats significantly alleviated diabetes-induced retinal vascular leakage and retinal inflammation. Furthermore, PPARα overexpression inhibited endothelial cell migration and proliferation. These findings revealed that diabetes-induced down-regulation of PPARα plays an important role in DR. Up-regulation or activation of PPARα may represent a novel therapeutic strategy for DR.
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