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Payne S, Neal A, De Val S. Transcription factors regulating vasculogenesis and angiogenesis. Dev Dyn 2024; 253:28-58. [PMID: 36795082 PMCID: PMC10952167 DOI: 10.1002/dvdy.575] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Revised: 02/06/2023] [Accepted: 02/06/2023] [Indexed: 02/17/2023] Open
Abstract
Transcription factors (TFs) play a crucial role in regulating the dynamic and precise patterns of gene expression required for the initial specification of endothelial cells (ECs), and during endothelial growth and differentiation. While sharing many core features, ECs can be highly heterogeneous. Differential gene expression between ECs is essential to pattern the hierarchical vascular network into arteries, veins and capillaries, to drive angiogenic growth of new vessels, and to direct specialization in response to local signals. Unlike many other cell types, ECs have no single master regulator, instead relying on differing combinations of a necessarily limited repertoire of TFs to achieve tight spatial and temporal activation and repression of gene expression. Here, we will discuss the cohort of TFs known to be involved in directing gene expression during different stages of mammalian vasculogenesis and angiogenesis, with a primary focus on development.
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Affiliation(s)
- Sophie Payne
- Department of Physiology, Anatomy and GeneticsInstitute of Developmental and Regenerative Medicine, University of OxfordOxfordUK
| | - Alice Neal
- Department of Physiology, Anatomy and GeneticsInstitute of Developmental and Regenerative Medicine, University of OxfordOxfordUK
| | - Sarah De Val
- Department of Physiology, Anatomy and GeneticsInstitute of Developmental and Regenerative Medicine, University of OxfordOxfordUK
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2
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Li T, Conroy KL, Kim AM, Halmai J, Gao K, Moreno E, Wang A, Passerini AG, Nolta JA, Zhou P. Role of MEF2C in the Endothelial Cells Derived from Human Induced Pluripotent Stem Cells. Stem Cells 2023; 41:341-353. [PMID: 36639926 PMCID: PMC10128960 DOI: 10.1093/stmcls/sxad005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Accepted: 01/08/2023] [Indexed: 01/15/2023]
Abstract
Human induced pluripotent stem cells (hiPSCs) not only provide an abundant source of vascular cells for potential therapeutic applications in vascular disease but also constitute an excellent model for understanding the mechanisms that regulate the differentiation and the functionality of vascular cells. Here, we reported that myocyte enhancer factor 2C (MEF2C) transcription factor, but not any other members of the MEF2 family, was robustly upregulated during the differentiation of vascular progenitors and endothelial cells (ECs) from hiPSCs. Vascular endothelial growth factors (VEGF) strongly induced MEF2C expression in endothelial lineage cells. The specific upregulation of MEF2C during the commitment of endothelial lineage was dependent on the extracellular signal regulated kinase (ERK). Moreover, knockdown of MEF2C with shRNA in hiPSCs did not affect the differentiation of ECs from these hiPSCs, but greatly reduced the migration and tube formation capacity of the hiPSC-derived ECs. Through a chromatin immunoprecipitation-sequencing, genome-wide RNA-sequencing, quantitative RT-PCR, and immunostaining analyses of the hiPSC-derived endothelial lineage cells with MEF2C inhibition or knockdown compared to control hiPSC-derived ECs, we identified TNF-related apoptosis inducing ligand (TRAIL) and transmembrane protein 100 (TMEM100) as novel targets of MEF2C. This study demonstrates an important role for MEF2C in regulating human EC functions and highlights MEF2C and its downstream effectors as potential targets to treat vascular malfunction-associated diseases.
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Affiliation(s)
- Tao Li
- School of Medicine, Hunan Normal University, Changsha, Hunan, People’s Republic of China
- Stem Cell Program and Department of Internal Medicine, University of California Davis Medical Center, Sacramento, CA, USA
| | - Kelsey L Conroy
- Stem Cell Program and Department of Internal Medicine, University of California Davis Medical Center, Sacramento, CA, USA
| | - Amy M Kim
- Stem Cell Program and Department of Internal Medicine, University of California Davis Medical Center, Sacramento, CA, USA
| | - Julian Halmai
- Stem Cell Program and Department of Internal Medicine, University of California Davis Medical Center, Sacramento, CA, USA
- Department of Neurology, University of California Davis School of Medicine, Sacramento, CA, USA
- University of California Davis Gene Therapy Center, Sacramento, CA, USA
| | - Kewa Gao
- Department of Surgery, University of California Davis, Sacramento, CA, USA
| | - Emily Moreno
- Department of Biomedical Engineering, University of California Davis, Davis, CA, USA
| | - Aijun Wang
- Department of Surgery, University of California Davis, Sacramento, CA, USA
- Department of Biomedical Engineering, University of California Davis, Davis, CA, USA
| | - Anthony G Passerini
- Department of Biomedical Engineering, University of California Davis, Davis, CA, USA
| | - Jan A Nolta
- Stem Cell Program and Department of Internal Medicine, University of California Davis Medical Center, Sacramento, CA, USA
- University of California Davis Gene Therapy Center, Sacramento, CA, USA
| | - Ping Zhou
- Stem Cell Program and Department of Internal Medicine, University of California Davis Medical Center, Sacramento, CA, USA
- University of California Davis Gene Therapy Center, Sacramento, CA, USA
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Parab S, Setten E, Astanina E, Bussolino F, Doronzo G. The tissue-specific transcriptional landscape underlines the involvement of endothelial cells in health and disease. Pharmacol Ther 2023; 246:108418. [PMID: 37088448 DOI: 10.1016/j.pharmthera.2023.108418] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2022] [Revised: 03/23/2023] [Accepted: 04/17/2023] [Indexed: 04/25/2023]
Abstract
Endothelial cells (ECs) that line vascular and lymphatic vessels are being increasingly recognized as important to organ function in health and disease. ECs participate not only in the trafficking of gases, metabolites, and cells between the bloodstream and tissues but also in the angiocrine-based induction of heterogeneous parenchymal cells, which are unique to their specific tissue functions. The molecular mechanisms regulating EC heterogeneity between and within different tissues are modeled during embryogenesis and become fully established in adults. Any changes in adult tissue homeostasis induced by aging, stress conditions, and various noxae may reshape EC heterogeneity and induce specific transcriptional features that condition a functional phenotype. Heterogeneity is sustained via specific genetic programs organized through the combinatory effects of a discrete number of transcription factors (TFs) that, at the single tissue-level, constitute dynamic networks that are post-transcriptionally and epigenetically regulated. This review is focused on outlining the TF-based networks involved in EC specialization and physiological and pathological stressors thought to modify their architecture.
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Affiliation(s)
- Sushant Parab
- Department of Oncology, University of Torino, IT, Italy; Candiolo Cancer Institute-IRCCS-FPO, Candiolo, Torino, IT, Italy
| | - Elisa Setten
- Department of Oncology, University of Torino, IT, Italy; Candiolo Cancer Institute-IRCCS-FPO, Candiolo, Torino, IT, Italy
| | - Elena Astanina
- Candiolo Cancer Institute-IRCCS-FPO, Candiolo, Torino, IT, Italy
| | - Federico Bussolino
- Department of Oncology, University of Torino, IT, Italy; Candiolo Cancer Institute-IRCCS-FPO, Candiolo, Torino, IT, Italy.
| | - Gabriella Doronzo
- Department of Oncology, University of Torino, IT, Italy; Candiolo Cancer Institute-IRCCS-FPO, Candiolo, Torino, IT, Italy
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4
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CD36 + cancer-associated fibroblasts provide immunosuppressive microenvironment for hepatocellular carcinoma via secretion of macrophage migration inhibitory factor. Cell Discov 2023; 9:25. [PMID: 36878933 PMCID: PMC9988869 DOI: 10.1038/s41421-023-00529-z] [Citation(s) in RCA: 46] [Impact Index Per Article: 46.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Accepted: 02/12/2023] [Indexed: 03/08/2023] Open
Abstract
Hepatocellular carcinoma (HCC) is an immunotherapy-resistant malignancy characterized by high cellular heterogeneity. The diversity of cell types and the interplay between tumor and non-tumor cells remain to be clarified. Single cell RNA sequencing of human and mouse HCC tumors revealed heterogeneity of cancer-associated fibroblast (CAF). Cross-species analysis determined the prominent CD36+ CAFs exhibited high-level lipid metabolism and expression of macrophage migration inhibitory factor (MIF). Lineage-tracing assays showed CD36+CAFs were derived from hepatic stellate cells. Furthermore, CD36 mediated oxidized LDL uptake-dependent MIF expression via lipid peroxidation/p38/CEBPs axis in CD36+ CAFs, which recruited CD33+myeloid-derived suppressor cells (MDSCs) in MIF- and CD74-dependent manner. Co-implantation of CD36+ CAFs with HCC cells promotes HCC progression in vivo. Finally, CD36 inhibitor synergizes with anti-PD-1 immunotherapy by restoring antitumor T-cell responses in HCC. Our work underscores the importance of elucidating the function of specific CAF subset in understanding the interplay between the tumor microenvironment and immune system.
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Zaidi SAH, Lemtalsi T, Xu Z, Santana I, Sandow P, Labazi L, Caldwell RW, Caldwell RB, Rojas MA. Role of acyl-coenzyme A: cholesterol transferase 1 (ACAT1) in retinal neovascularization. J Neuroinflammation 2023; 20:14. [PMID: 36691048 PMCID: PMC9869542 DOI: 10.1186/s12974-023-02700-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Accepted: 01/13/2023] [Indexed: 01/24/2023] Open
Abstract
BACKGROUND We have investigated the efficacy of a new strategy to limit pathological retinal neovascularization (RNV) during ischemic retinopathy by targeting the cholesterol metabolizing enzyme acyl-coenzyme A: cholesterol transferase 1 (ACAT1). Dyslipidemia and cholesterol accumulation have been strongly implicated in promoting subretinal NV. However, little is known about the role of cholesterol metabolism in RNV. Here, we tested the effects of inhibiting ACAT1 on pathological RNV in the mouse model of oxygen-induced retinopathy (OIR). METHODS In vivo studies used knockout mice that lack the receptor for LDL cholesterol (LDLR-/-) and wild-type mice. The wild-type mice were treated with a specific inhibitor of ACAT1, K604 (10 mg/kg, i.p) or vehicle (PBS) during OIR. In vitro studies used human microglia exposed to oxygen-glucose deprivation (OGD) and treated with the ACAT1 inhibitor (1 μM) or PBS. RESULTS Analysis of OIR retinas showed that increased expression of inflammatory mediators and pathological RNV were associated with significant increases in expression of the LDLR, increased accumulation of neutral lipids, and formation of toxic levels of cholesterol ester (CE). Deletion of the LDLR completely blocked OIR-induced RNV and significantly reduced the AVA. The OIR-induced increase in CE formation was accompanied by significant increases in expression of ACAT1, VEGF and inflammatory factors (TREM1 and MCSF) (p < 0.05). ACAT1 was co-localized with TREM1, MCSF, and macrophage/microglia makers (F4/80 and Iba1) in areas of RNV. Treatment with K604 prevented retinal accumulation of neutral lipids and CE formation, inhibited RNV, and decreased the AVA as compared to controls (p < 0.05). The treatment also blocked upregulation of LDLR, ACAT1, TREM1, MCSF, and inflammatory cytokines but did not alter VEGF expression. K604 treatment of microglia cells also blocked the effects of OGD in increasing expression of ACAT1, TREM1, and MCSF without altering VEGF expression. CONCLUSIONS OIR-induced RNV is closely associated with increases in lipid accumulation and CE formation along with increased expression of LDLR, ACAT1, TREM1, and MCSF. Inhibiting ACAT1 blocked these effects and limited RNV independently of alterations in VEGF expression. This pathway offers a novel strategy to limit vascular injury during ischemic retinopathy.
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Affiliation(s)
- Syed A H Zaidi
- Vascular Biology Center, Augusta University, 1460 Laney Walker Blvd, Augusta, GA, 30912-2500, USA.,Culver Vision Discovery Institute, Augusta University, Augusta, GA, USA
| | - Tahira Lemtalsi
- Vascular Biology Center, Augusta University, 1460 Laney Walker Blvd, Augusta, GA, 30912-2500, USA.,Culver Vision Discovery Institute, Augusta University, Augusta, GA, USA
| | - Zhimin Xu
- Vascular Biology Center, Augusta University, 1460 Laney Walker Blvd, Augusta, GA, 30912-2500, USA.,Culver Vision Discovery Institute, Augusta University, Augusta, GA, USA
| | - Isabella Santana
- Vascular Biology Center, Augusta University, 1460 Laney Walker Blvd, Augusta, GA, 30912-2500, USA
| | - Porsche Sandow
- Culver Vision Discovery Institute, Augusta University, Augusta, GA, USA.,Department of Pharmacology and Toxicology, Augusta University, Augusta, GA, USA
| | - Leila Labazi
- Vascular Biology Center, Augusta University, 1460 Laney Walker Blvd, Augusta, GA, 30912-2500, USA
| | - Robert W Caldwell
- Culver Vision Discovery Institute, Augusta University, Augusta, GA, USA.,Department of Pharmacology and Toxicology, Augusta University, Augusta, GA, USA
| | - Ruth B Caldwell
- Vascular Biology Center, Augusta University, 1460 Laney Walker Blvd, Augusta, GA, 30912-2500, USA. .,Culver Vision Discovery Institute, Augusta University, Augusta, GA, USA. .,Department of Cellular Biology and Anatomy, Augusta University, Augusta, GA, USA.
| | - Modesto A Rojas
- Vascular Biology Center, Augusta University, 1460 Laney Walker Blvd, Augusta, GA, 30912-2500, USA. .,Culver Vision Discovery Institute, Augusta University, Augusta, GA, USA. .,Department of Pharmacology and Toxicology, Augusta University, Augusta, GA, USA.
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Zhou L, Xu Z, Oh Y, Gamuyao R, Lee G, Xie Y, Cho H, Lee S, Duh EJ. Myeloid cell modulation by a GLP-1 receptor agonist regulates retinal angiogenesis in ischemic retinopathy. JCI Insight 2021; 6:93382. [PMID: 34673570 PMCID: PMC8675187 DOI: 10.1172/jci.insight.93382] [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: 01/04/2021] [Accepted: 10/20/2021] [Indexed: 01/04/2023] Open
Abstract
Ischemic retinopathies including diabetic retinopathy are major causes of blindness. Although neurons and Müller glia are recognized as important regulators of reparative and pathologic angiogenesis, the role of mononuclear phagocytes (MPs) — particularly microglia, the resident retinal immune cells — is unclear. Here, we found MP activation in human diabetic retinopathy, especially in neovessels from human neovascular membranes in proliferative retinopathy, including TNF-α expression. There was similar activation in the mouse oxygen-induced retinopathy (OIR) model of ischemia-induced neovascularization. Glucagon-like peptide-1 receptor (GLP-1R) agonists are in clinical use for glycemic control in diabetes and are also known to modulate microglia. Herein, we investigated the effect of a long-acting GLP-1R agonist, NLY01. Following intravitreal administration, NLY01 selectively localized to MPs in retina with OIR. NLY01 modulated MPs but not retinal endothelial cell viability, apoptosis, and tube formation in vitro. In OIR, NLY01 treatment inhibited MP infiltration and activation, including MP expression of cytokines in vivo. NLY01 significantly suppressed global induction of retinal inflammatory cytokines, promoted reparative angiogenesis, and suppressed pathologic retinal neovascularization. Collectively, these findings indicate the important role of mononuclear phagocytes in regulation of retinal vascularization in ischemia and suggest modulation of MPs as a potentially new treatment strategy for ischemic retinopathies.
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Affiliation(s)
| | | | - Yumin Oh
- Wilmer Eye Institute and.,The Russell H. Morgan Department of Radiology and Radiological Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | | | | | | | | | - Seulki Lee
- Wilmer Eye Institute and.,The Russell H. Morgan Department of Radiology and Radiological Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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Xia F, Xu Y, Zhang X, Lyu J, Zhao P. Competing endogenous RNA network associated with oxygen-induced retinopathy: Expression of the network and identification of the MALAT1/miR-124-3p/EGR1 regulatory axis. Exp Cell Res 2021; 408:112783. [PMID: 34469714 DOI: 10.1016/j.yexcr.2021.112783] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2021] [Revised: 07/19/2021] [Accepted: 08/11/2021] [Indexed: 02/07/2023]
Abstract
Retinopathy of prematurity (ROP) is a severe retinal dysfunction in prematurely born babies. The relationship between non-coding RNAs and retinopathy of prematurity (ROP) remain unclear. Microarray analysis of lncRNAs, miRNAs, and mRNAs was conducted in a mouse model of ROP. A competing endogenous RNA (ceRNA) network was constructed. The relationship among MALAT1, miR-124-3p, and Early growth response protein 1 (EGR1) was assessed in hypoxia-induced primary human umbilical vein endothelial cells (HUVECs) and ROP mouse model. In the study, we found 2252 lncRNAs, 1239 mRNAs, and 36 miRNAs were differentially regulated. ceRNA network consisting of 21 lncRNAs, 10 miRNAs, and 19 mRNAs was established. Of the most down-regulated miRNAs, miR-124-3p was selected for additional study. miR-124-3p ceased the migration and proliferation of primary HUVECs in hypoxic conditions, and directly suppressed EGR1. Additionally, MALAT1 directly sponged miR-124-3p. Knockdown of MALAT1 decreased EGR1 expression and inhibited the migration and proliferation of primary HUVECs in hypoxia. Furthermore, these changes were rescued by depletion of miR-124-3p. In vivo, intravitreal injection of miR-124-3p, shMALAT1 decreased EGR1 expression and markedly suppressed retinal neovascularization in OIR models. Intravitreal injection of shMALAT1 and miR-124-3p antagomir at the same time can promote retinal neovascularization, which reversed the suppression of retinal neovascularization functioned by shMALAT1. In conclusion, the expression profiles of lncRNAs and miRNAs and the ceRNA network in a mouse model of ROP may be indicative of the underlying mechanisms of retinal angiogenesis and neural activity. The MALAT1/miR-124-3p/EGR1 regulatory axis is partly responsible for retinal neovascularization, which may provide a novel theoretical basis for the pathogenesis of ROP.
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Affiliation(s)
- Fengjie Xia
- Department of Ophthalmology, Xinhua Hospital, Affiliated to Medicine School of Shanghai Jiaotong University, No. 1665, Kongjiang Road, Shanghai, 200092, China
| | - Yu Xu
- Department of Ophthalmology, Xinhua Hospital, Affiliated to Medicine School of Shanghai Jiaotong University, No. 1665, Kongjiang Road, Shanghai, 200092, China
| | - Xiang Zhang
- Department of Ophthalmology, Xinhua Hospital, Affiliated to Medicine School of Shanghai Jiaotong University, No. 1665, Kongjiang Road, Shanghai, 200092, China
| | - Jiao Lyu
- Department of Ophthalmology, Xinhua Hospital, Affiliated to Medicine School of Shanghai Jiaotong University, No. 1665, Kongjiang Road, Shanghai, 200092, China.
| | - Peiquan Zhao
- Department of Ophthalmology, Xinhua Hospital, Affiliated to Medicine School of Shanghai Jiaotong University, No. 1665, Kongjiang Road, Shanghai, 200092, China.
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Townes-Anderson E, Halasz E, Wang W, Zarbin M. Coming of Age for the Photoreceptor Synapse. Invest Ophthalmol Vis Sci 2021; 62:24. [PMID: 34550300 PMCID: PMC8475281 DOI: 10.1167/iovs.62.12.24] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Purpose To discuss the potential contribution of rod and cone synapses to the loss of visual function in retinal injury and disease. Methods The published literature and the authors' own work were reviewed. Results Retinal detachment is used as a case study of rod spherule and cone pedicle plasticity after injury. Both rod and cone photoreceptors terminals are damaged after detachment although the structural changes observed are only partially overlapping. For second-order neurons, only those associated with rod spherules respond consistently to injury by remodeling. Examination of signaling pathways involved in plasticity of conventional synapses and in neural development has been and may continue to be productive in discovering novel therapeutic targets. Rho kinase (ROCK) inhibition is an example of therapy that may reduce synaptic damage by preserving normal synaptic structure of rod and cone cells. Conclusions We hypothesize that synaptic damage contributes to poor visual restoration after otherwise successful anatomical repair of retinal detachment. A similar situation may exist for patients with degenerative retinal disease. Thus, synaptic structure and function should be routinely studied, as this information may disclose therapeutic strategies to mitigate visual loss.
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Affiliation(s)
- Ellen Townes-Anderson
- Department of Pharmacology, Physiology, and Neuroscience, Rutgers New Jersey Medical School, Newark, New Jersey, United States
| | - Eva Halasz
- Department of Pharmacology, Physiology, and Neuroscience, Rutgers New Jersey Medical School, Newark, New Jersey, United States
| | - Weiwei Wang
- Schepens Eye Research Institute and Massachusetts Eye and Ear Infirmary, Department of Ophthalmology, Harvard University, Boston, Massachusetts, United States
| | - Marco Zarbin
- Institute of Ophthalmology and Visual Science, Rutgers New Jersey Medical School, Newark, New Jersey, United States
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Genome-wide association study of trypanosome prevalence and morphometric traits in purebred and crossbred Baoulé cattle of Burkina Faso. PLoS One 2021; 16:e0255089. [PMID: 34351956 PMCID: PMC8341487 DOI: 10.1371/journal.pone.0255089] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Accepted: 07/09/2021] [Indexed: 11/27/2022] Open
Abstract
In this study, single-SNP GWAS analyses were conducted to find regions affecting tolerance against trypanosomosis and morphometrics traits in purebred and crossbred Baoulé cattle of Burkina Faso. The trypanosomosis status (positive and negative) and a wide set of morphological traits were recorded for purebred Baoulé and crossbred Zebu x Baoulé cattle, and genotyped with the Illumina Bovine SNP50 BeadChip. After quality control, 36,203 SNPs and 619 animals including 343 purebred Baoulé and 279 crossbreds were used for the GWAS analyses. Several important genes were found that can influence morphological parameters. Although there were no genes identified with a reported strong connection to size traits, many of them were previously identified in various growth-related studies. A re-occurring theme for the genes residing in the regions identified by the most significant SNPs was pleiotropic effect on growth of the body and the cardiovascular system. Regarding trypanosomosis tolerance, two potentially important regions were identified in purebred Baoulé on chromosomes 16 and 24, containing the CFH, CRBN, TRNT1 and, IL5RA genes, and one additional genomic region in Baoulé, x Zebu crossbreds on chromosome 5, containing MGAT4C and NTS. Almost all of these regions and genes were previously related to the trait of interest, while the CRBN gene was to our knowledge presented in the context of trypanosomiasis tolerance for the first time.
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Lu YW, Martino N, Gerlach BD, Lamar JM, Vincent PA, Adam AP, Schwarz JJ. MEF2 (Myocyte Enhancer Factor 2) Is Essential for Endothelial Homeostasis and the Atheroprotective Gene Expression Program. Arterioscler Thromb Vasc Biol 2021; 41:1105-1123. [PMID: 33406884 DOI: 10.1161/atvbaha.120.314978] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
OBJECTIVE Atherosclerosis predominantly forms in regions of oscillatory shear stress while regions of laminar shear stress are protected. This protection is partly through the endothelium in laminar flow regions expressing an anti-inflammatory and antithrombotic gene expression program. Several molecular pathways transmitting these distinct flow patterns to the endothelium have been defined. Our objective is to define the role of the MEF2 (myocyte enhancer factor 2) family of transcription factors in promoting an atheroprotective endothelium. Approach and Results: Here, we show through endothelial-specific deletion of the 3 MEF2 factors in the endothelium, Mef2a, -c, and -d, that MEF2 is a critical regulator of vascular homeostasis. MEF2 deficiency results in systemic inflammation, hemorrhage, thrombocytopenia, leukocytosis, and rapid lethality. Transcriptome analysis reveals that MEF2 is required for normal regulation of 3 pathways implicated in determining the flow responsiveness of the endothelium. Specifically, MEF2 is required for expression of Klf2 and Klf4, 2 partially redundant factors essential for promoting an anti-inflammatory and antithrombotic endothelium. This critical requirement results in phenotypic similarities between endothelial-specific deletions of Mef2a/c/d and Klf2/4. In addition, MEF2 regulates the expression of Notch family genes, Notch1, Dll1, and Jag1, which also promote an atheroprotective endothelium. In contrast to these atheroprotective pathways, MEF2 deficiency upregulates an atherosclerosis promoting pathway through increasing the amount of TAZ (transcriptional coactivator with PDZ-binding motif). CONCLUSIONS Our results implicate MEF2 as a critical upstream regulator of several transcription factors responsible for gene expression programs that affect development of atherosclerosis and promote an anti-inflammatory and antithrombotic endothelium. Graphic Abstract: A graphic abstract is available for this article.
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Affiliation(s)
- Yao Wei Lu
- Department of Molecular and Cellular Physiology (Y.W.L., N.M., B.D.G., J.M.L., P.A.V., A.P.A., J.J.S.), Albany Medical College, NY
| | - Nina Martino
- Department of Molecular and Cellular Physiology (Y.W.L., N.M., B.D.G., J.M.L., P.A.V., A.P.A., J.J.S.), Albany Medical College, NY
| | - Brennan D Gerlach
- Department of Molecular and Cellular Physiology (Y.W.L., N.M., B.D.G., J.M.L., P.A.V., A.P.A., J.J.S.), Albany Medical College, NY
| | - John M Lamar
- Department of Molecular and Cellular Physiology (Y.W.L., N.M., B.D.G., J.M.L., P.A.V., A.P.A., J.J.S.), Albany Medical College, NY
| | - Peter A Vincent
- Department of Molecular and Cellular Physiology (Y.W.L., N.M., B.D.G., J.M.L., P.A.V., A.P.A., J.J.S.), Albany Medical College, NY
| | - Alejandro P Adam
- Department of Molecular and Cellular Physiology (Y.W.L., N.M., B.D.G., J.M.L., P.A.V., A.P.A., J.J.S.), Albany Medical College, NY.,Department of Ophthalmology (A.P.A.), Albany Medical College, NY
| | - John J Schwarz
- Department of Molecular and Cellular Physiology (Y.W.L., N.M., B.D.G., J.M.L., P.A.V., A.P.A., J.J.S.), Albany Medical College, NY
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11
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Feng J, Chen L, Jiang Y, Tao Y. The Role of Apelin/APJ in a Mouse Model of Oxygen-induced Retinopathy. Invest Ophthalmol Vis Sci 2021; 61:47. [PMID: 32729912 PMCID: PMC7425705 DOI: 10.1167/iovs.61.8.47] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Purpose The aim of this study was to investigate apelin and its potential neovascularization role in retinopathy of prematurity (ROP) along with the inhibitory effects of its antagonist. Methods We used an oxygen-induced retinopathy (OIR) mouse model to explore the progress of ROP. Apelin and angiotensin receptor-like 1 APJ expressions were examined in the retina using immunohistochemistry, quantitative polymerase chain reaction, and Western blot analysis. Additionally, the retina was examined by whole-mount staining to evaluate the retinal vessel area, vessel density, capillary width, and the number and length of tip cells. The expression of the phosphorylated mTOR (p-mTOR), p-PI3K/Akt, and p-Erk signaling pathway was also evaluated using Western blot analysis. Results Apelin promoted the development of superficial and deep retinal blood vessels, especially for tip cells during the physical development of retinal vessels. Additionally, apelin stimulated the density of the peripheral retinal zone vessels in OIR mice. The apelin and APJ expression levels significantly increased for the OIR model during their hypoxic phase. Next, we found that apelin mRNA levels in the OIR mice peaked at six hours after return to ambient conditions at P12, whereas the APJ mRNA levels peaked later at P17. Furthermore, the expression of p-mTOR, p-Akt, and p-Erk were all up-regulated in OIR mice whereas F13A suppressed them instead. Conclusions Our results suggest that apelin/APJ signaling pathway is a key factor for hypoxia-induced pathologic angiogenesis, which is a very promising new target for the treatment of ROP.
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12
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Tsang JKW, Liu J, Lo ACY. Vascular and Neuronal Protection in the Developing Retina: Potential Therapeutic Targets for Retinopathy of Prematurity. Int J Mol Sci 2019; 20:E4321. [PMID: 31484463 PMCID: PMC6747312 DOI: 10.3390/ijms20174321] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Revised: 08/21/2019] [Accepted: 08/29/2019] [Indexed: 12/13/2022] Open
Abstract
Retinopathy of prematurity (ROP) is a common retinal disease in preterm babies. To prolong the lives of preterm babies, high oxygen is provided to mimic the oxygen level in the intrauterine environment for postnatal organ development. However, hyperoxia-hypoxia induced pathological events occur when babies return to room air, leading to ROP with neuronal degeneration and vascular abnormality that affects retinal functions. With advances in neonatal intensive care, it is no longer uncommon for increased survival of very-low-birth-weight preterm infants, which, therefore, increased the incidence of ROP. ROP is now a major cause of preventable childhood blindness worldwide. Current proven treatment for ROP is limited to invasive retinal ablation, inherently destructive to the retina. The lack of pharmacological treatment for ROP creates a great need for effective and safe therapies in these developing infants. Therefore, it is essential to identify potential therapeutic agents that may have positive ROP outcomes, especially in preserving retinal functions. This review gives an overview of various agents in their efficacy in reducing retinal damages in cell culture tests, animal experiments and clinical studies. New perspectives along the neuroprotective pathways in the developing retina are also reviewed.
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Affiliation(s)
- Jessica K W Tsang
- Department of Ophthalmology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China
| | - Jin Liu
- Department of Ophthalmology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China
| | - Amy C Y Lo
- Department of Ophthalmology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China.
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13
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Materna SC, Sinha T, Barnes RM, Lammerts van Bueren K, Black BL. Cardiovascular development and survival require Mef2c function in the myocardial but not the endothelial lineage. Dev Biol 2018; 445:170-177. [PMID: 30521808 DOI: 10.1016/j.ydbio.2018.12.002] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Revised: 11/28/2018] [Accepted: 12/03/2018] [Indexed: 01/27/2023]
Abstract
MEF2C is a member of the highly conserved MEF2 family of transcription factors and is a key regulator of cardiovascular development. In mice, Mef2c is expressed in the developing heart and vasculature, including the endothelium. Loss of Mef2c function in germline knockout mice leads to early embryonic demise and profound developmental abnormalities in the cardiovascular system. Previous attempts to uncover the cause of embryonic lethality by specifically disrupting Mef2c function in the heart or vasculature failed to recapitulate the global Mef2c knockout phenotype and instead resulted in relatively minor defects that did not compromise viability or result in significant cardiovascular defects. However, previous studies examined the requirement of Mef2c in the myocardial and endothelial lineages using Cre lines that begin to be expressed after the expression of Mef2c has already commenced. Here, we tested the requirement of Mef2c in the myocardial and endothelial lineages using conditional knockout approaches in mice with Cre lines that deleted Mef2c prior to onset of its expression in embryonic development. We found that deletion of Mef2c in the early myocardial lineage using Nkx2-5Cre resulted in cardiac and vascular abnormalities that were indistinguishable from the defects in the global Mef2c knockout. In contrast, early deletion of Mef2c in the vascular endothelium using an Etv2::Cre line active prior to the onset of Mef2c expression resulted in viable offspring that were indistinguishable from wild type controls with no overt defects in vascular development, despite nearly complete early deletion of Mef2c in the vascular endothelium. Thus, these studies support the idea that the requirement of MEF2C for vascular development is secondary to its requirement in the heart and suggest that the observed failure in vascular remodeling in Mef2c knockout mice results from defective heart function.
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Affiliation(s)
- Stefan C Materna
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA 94143, USA; Department of Molecular Cell Biology, School of Natural Sciences, University of California, Merced, Merced, CA 95343, USA
| | - Tanvi Sinha
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Ralston M Barnes
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Kelly Lammerts van Bueren
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Brian L Black
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA 94143, USA; Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA 94143, USA.
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14
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Tsuji-Tamura K, Ogawa M. Morphology regulation in vascular endothelial cells. Inflamm Regen 2018; 38:25. [PMID: 30214642 PMCID: PMC6130072 DOI: 10.1186/s41232-018-0083-8] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Accepted: 08/07/2018] [Indexed: 12/22/2022] Open
Abstract
Morphological change in endothelial cells is an initial and crucial step in the process of establishing a functional vascular network. Following or associated with differentiation and proliferation, endothelial cells elongate and assemble into linear cord-like vessels, subsequently forming a perfusable vascular tube. In vivo and in vitro studies have begun to outline the underlying genetic and signaling mechanisms behind endothelial cell morphology regulation. This review focuses on the transcription factors and signaling pathways regulating endothelial cell behavior, involved in morphology, during vascular development.
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Affiliation(s)
- Kiyomi Tsuji-Tamura
- 1Department of Cell Differentiation, Institute of Molecular Embryology and Genetics, Kumamoto University, Kumamoto, 860-0811 Japan.,2Present Address: Oral Biochemistry and Molecular Biology, Department of Oral Health Science, Faculty of Dental Medicine and Graduate School of Dental Medicine, Hokkaido University, Sapporo, 060-8586 Japan
| | - Minetaro Ogawa
- 1Department of Cell Differentiation, Institute of Molecular Embryology and Genetics, Kumamoto University, Kumamoto, 860-0811 Japan
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15
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Kamalden TA, Macgregor-Das AM, Kannan SM, Dunkerly-Eyring B, Khaliddin N, Xu Z, Fusco AP, Yazib SA, Chow RC, Duh EJ, Halushka MK, Steenbergen C, Das S. Exosomal MicroRNA-15a Transfer from the Pancreas Augments Diabetic Complications by Inducing Oxidative Stress. Antioxid Redox Signal 2017; 27:913-930. [PMID: 28173719 PMCID: PMC5649125 DOI: 10.1089/ars.2016.6844] [Citation(s) in RCA: 87] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
AIMS MicroRNAs (miRNAs), one type of noncoding RNA, modulate post-transcriptional gene expression in various pathogenic pathways in type 2 diabetes (T2D). Currently, little is known about how miRNAs influence disease pathogenesis by targeting cells at a distance. The purpose of this study was to investigate the role of exosomal miRNAs during T2D. RESULTS We show that miR-15a is increased in the plasma of diabetic patients, correlating with disease severity. miR-15 plays an important role in insulin production in pancreatic β-cells. By culturing rat pancreatic β-cells (INS-1) cells in high-glucose media, we identified a source of increased miR-15a in the blood as exosomes secreted by pancreatic β-cells. We postulate that miR-15a, produced in pancreatic β-cells, can enter the bloodstream and contribute to retinal injury. miR-15a overexpression in Müller cells can be induced by exposing Müller cells to exosomes derived from INS-1 cells under high-glucose conditions and results in oxidative stress by targeting Akt3, which leads to apoptotic cell death. The in vivo relevance of these findings is supported by results from high-fat diet and pancreatic β-cell-specific miR-15a-/- mice. INNOVATION This study highlights an important and underappreciated mechanism of remote cell-cell communication (exosomal transfer of miRNA) and its influence on the development of T2D complications. CONCLUSION Our findings suggest that circulating miR-15a contributes to the pathogenesis of diabetes and supports the concept that miRNAs released by one cell type can travel through the circulation and play a role in disease progression via their transfer to different cell types, inducing oxidative stress and cell injury. Antioxid. Redox Signal. 27, 913-930.
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Affiliation(s)
- Tengku Ain Kamalden
- 1 University of Malaya Eye Research Centre, Department of Ophthalmology, University of Malaya , Kuala Lumpur, Malaysia
| | | | - Sangeetha Marimuthu Kannan
- 2 Department of Pathology, Johns Hopkins University , Baltimore, Maryland.,3 School of Life Sciences, B.S. Abdur Rahman University , Chennai, India
| | | | - Nurliza Khaliddin
- 1 University of Malaya Eye Research Centre, Department of Ophthalmology, University of Malaya , Kuala Lumpur, Malaysia
| | - Zhenhua Xu
- 4 Department of Ophthalmology, Johns Hopkins University , Baltimore, Maryland
| | | | - Syatirah Abu Yazib
- 1 University of Malaya Eye Research Centre, Department of Ophthalmology, University of Malaya , Kuala Lumpur, Malaysia
| | - Rhuen Chiou Chow
- 1 University of Malaya Eye Research Centre, Department of Ophthalmology, University of Malaya , Kuala Lumpur, Malaysia
| | - Elia J Duh
- 4 Department of Ophthalmology, Johns Hopkins University , Baltimore, Maryland
| | - Marc K Halushka
- 2 Department of Pathology, Johns Hopkins University , Baltimore, Maryland
| | | | - Samarjit Das
- 2 Department of Pathology, Johns Hopkins University , Baltimore, Maryland
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16
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Zhang R, Sui L, Hong X, Yang M, Li W. MiR-448 promotes vascular smooth muscle cell proliferation and migration in through directly targeting MEF2C. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2017; 24:22294-22300. [PMID: 28799067 DOI: 10.1007/s11356-017-9771-1] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Accepted: 07/13/2017] [Indexed: 06/07/2023]
Abstract
Abnormal proliferation and migration of vascular smooth muscle cells (VSMCs) is a critical process in various cardiovascular diseases such as coronary artery disease (CAD), atherosclerosis, stroke, and hypertension. MicroRNAs (miRNAs) are small, short, and noncoding RNAs that inhibit gene expression through binding to the 3'-UTR (3' untranslated regions) of target gene mRNAs. We showed that the expression of miR-448 was upregulated in VSMCs from coronary atherosclerotic plaques compared with normal coronary artery tissues. We also found that PDGF-bb promoted VSMCs proliferation and could induce miR-448 expression. Ectopic miR-448 expression induced VSMCs proliferation. Overexpression of miR-448 induced ki-67 mRNA and protein expression. Moreover, we identified MEF2C was a direct target of miR-448 in VSMCs. Overexpression of miR-448 promoted VSMCs migration. Furthermore, overexpression of MEF2C decreased miR-448-induced VSMCs proliferation and migration. These evidences suggested that miR-448 played an important role in the proliferation and migration of VSMCs.
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Affiliation(s)
- Ruihong Zhang
- Department of Cardiovascular, the First Affiliated Hospital of Harbin Medical University, Harbin, 150001, People's Republic of China
| | - Li Sui
- Department of Emergency, the First Affiliated Hospital of Harbin Medical University, Harbin, 150001, People's Republic of China
| | - Xiaojian Hong
- Department of Cardiovascular, the First Affiliated Hospital of Harbin Medical University, Harbin, 150001, People's Republic of China
| | - Mao Yang
- Department of Cardiovascular, the Fourth Affiliated Hospital of Harbin Medical University, Harbin, 150001, People's Republic of China
| | - Weimin Li
- Department of Cardiovascular, the First Affiliated Hospital of Harbin Medical University, Harbin, 150001, People's Republic of China.
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17
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A Critical Analysis of the Available In Vitro and Ex Vivo Methods to Study Retinal Angiogenesis. J Ophthalmol 2017; 2017:3034953. [PMID: 28848677 PMCID: PMC5564124 DOI: 10.1155/2017/3034953] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Revised: 06/20/2017] [Accepted: 06/28/2017] [Indexed: 12/15/2022] Open
Abstract
Angiogenesis is a biological process with a central role in retinal diseases. The choice of the ideal method to study angiogenesis, particularly in the retina, remains a problem. Angiogenesis can be assessed through in vitro and in vivo studies. In spite of inherent limitations, in vitro studies are faster, easier to perform and quantify, and typically less expensive and allow the study of isolated angiogenesis steps. We performed a systematic review of PubMed searching for original articles that applied in vitro or ex vivo angiogenic retinal assays until May 2017, presenting the available assays and discussing their applicability, advantages, and disadvantages. Most of the studies evaluated migration, proliferation, and tube formation of endothelial cells in response to inhibitory or stimulatory compounds. Other aspects of angiogenesis were studied by assessing cell permeability, adhesion, or apoptosis, as well as by implementing organotypic models of the retina. Emphasis is placed on how the methods are applied and how they can contribute to retinal angiogenesis comprehension. We also discuss how to choose the best cell culture to implement these methods. When applied together, in vitro and ex vivo studies constitute a powerful tool to improve retinal angiogenesis knowledge. This review provides support for researchers to better select the most suitable protocols in this field.
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18
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Liu C, Yao MD, Li CP, Shan K, Yang H, Wang JJ, Liu B, Li XM, Yao J, Jiang Q, Yan B. Silencing Of Circular RNA-ZNF609 Ameliorates Vascular Endothelial Dysfunction. Theranostics 2017; 7:2863-2877. [PMID: 28824721 PMCID: PMC5562221 DOI: 10.7150/thno.19353] [Citation(s) in RCA: 200] [Impact Index Per Article: 28.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Accepted: 05/08/2017] [Indexed: 12/23/2022] Open
Abstract
Vascular dysfunction is a hallmark of ischemic, cancer, and inflammatory diseases, contributing to disease progression. Circular RNAs (circRNAs) are endogenous non-coding RNAs, which have been reported to be abnormally expressed in many human diseases. In this study, we used retinal vasculature to determine the role of circular RNA in vascular dysfunction. We revealed that cZNF609 was significantly up-regulated upon high glucose and hypoxia stress in vivo and in vitro. cZNF609 silencing decreased retinal vessel loss and suppressed pathological angiogenesis in vivo. cZNF609 silencing increased endothelial cell migration and tube formation, and protected endothelial cell against oxidative stress and hypoxia stress in vitro. By contrast, transgenic overexpression of cZNF609 showed an opposite effects. cZNF609 acted as an endogenous miR-615-5p sponge to sequester and inhibit miR-615-5p activity, which led to increased MEF2A expression. MEF2A overexpression could rescue cZNF609 silencing-mediated effects on endothelial cell migration, tube formation, and apoptosis. Moreover, dysregulated cZNF609 expression was detected in the clinical samples of the patients with diabetes, hypertension, and coronary artery disease. Intervention of cZNF609 expression is promising therapy for vascular dysfunction.
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19
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Dong C, Yang XZ, Zhang CY, Liu YY, Zhou RB, Cheng QD, Yan EK, Yin DC. Myocyte enhancer factor 2C and its directly-interacting proteins: A review. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2017; 126:22-30. [DOI: 10.1016/j.pbiomolbio.2017.02.002] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Revised: 11/24/2016] [Accepted: 02/01/2017] [Indexed: 11/27/2022]
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20
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Lu YW, Lowery AM, Sun LY, Singer HA, Dai G, Adam AP, Vincent PA, Schwarz JJ. Endothelial Myocyte Enhancer Factor 2c Inhibits Migration of Smooth Muscle Cells Through Fenestrations in the Internal Elastic Lamina. Arterioscler Thromb Vasc Biol 2017; 37:1380-1390. [PMID: 28473437 DOI: 10.1161/atvbaha.117.309180] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Accepted: 04/25/2017] [Indexed: 12/30/2022]
Abstract
OBJECTIVE Laminar flow activates myocyte enhancer factor 2 (MEF2) transcription factors in vitro to induce expression of atheroprotective genes in the endothelium. Here we sought to establish the role of Mef2c in the vascular endothelium in vivo. APPROACH AND RESULTS To study endothelial Mef2c, we generated endothelial-specific deletion of Mef2c using Tie2-Cre or Cdh5-Cre-ERT2 and examined aortas and carotid arteries by en face immunofluorescence. We observed enhanced actin stress fiber formation in the Mef2c-deleted thoracic aortic endothelium (laminar flow region), similar to those observed in normal aortic inner curvature (disturbed flow region). Furthermore, Mef2c deletion resulted in the de novo formation of subendothelial intimal cells expressing markers of differentiated smooth muscle in the thoracic aortas and carotids. Lineage tracing showed that these cells were not of endothelial origin. To define early events in intimal development, we induced endothelial deletion of Mef2c and examined aortas at 4 and 12 weeks postinduction. The number of intimal cell clusters increased from 4 to 12 weeks, but the number of cells within a cluster peaked at 2 cells in both cases, suggesting ongoing migration but minimal proliferation. Moreover, we identified cells extending from the media through fenestrations in the internal elastic lamina into the intima, indicating transfenestral smooth muscle migration. Similar transfenestral migration was observed in wild-type carotid arteries ligated to induce neointimal formation. CONCLUSIONS These results indicate that endothelial Mef2c regulates the endothelial actin cytoskeleton and inhibits smooth muscle cell migration into the intima.
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Affiliation(s)
- Yao Wei Lu
- From the Department of Molecular and Cellular Physiology (Y.W.L., A.M.L., L.-Y.S., H.A.S., A.P.A., P.A.V., J.J.S.), and Department of Ophthalmology (A.P.A.), Albany Medical College, NY; Department of Biomedical Engineering, Rensselaer Polytechnic Institute, Troy, NY (G.D.); and Department of Bioengineering, Northeastern University, Boston, MA (G.D.)
| | - Anthony M Lowery
- From the Department of Molecular and Cellular Physiology (Y.W.L., A.M.L., L.-Y.S., H.A.S., A.P.A., P.A.V., J.J.S.), and Department of Ophthalmology (A.P.A.), Albany Medical College, NY; Department of Biomedical Engineering, Rensselaer Polytechnic Institute, Troy, NY (G.D.); and Department of Bioengineering, Northeastern University, Boston, MA (G.D.)
| | - Li-Yan Sun
- From the Department of Molecular and Cellular Physiology (Y.W.L., A.M.L., L.-Y.S., H.A.S., A.P.A., P.A.V., J.J.S.), and Department of Ophthalmology (A.P.A.), Albany Medical College, NY; Department of Biomedical Engineering, Rensselaer Polytechnic Institute, Troy, NY (G.D.); and Department of Bioengineering, Northeastern University, Boston, MA (G.D.)
| | - Harold A Singer
- From the Department of Molecular and Cellular Physiology (Y.W.L., A.M.L., L.-Y.S., H.A.S., A.P.A., P.A.V., J.J.S.), and Department of Ophthalmology (A.P.A.), Albany Medical College, NY; Department of Biomedical Engineering, Rensselaer Polytechnic Institute, Troy, NY (G.D.); and Department of Bioengineering, Northeastern University, Boston, MA (G.D.)
| | - Guohao Dai
- From the Department of Molecular and Cellular Physiology (Y.W.L., A.M.L., L.-Y.S., H.A.S., A.P.A., P.A.V., J.J.S.), and Department of Ophthalmology (A.P.A.), Albany Medical College, NY; Department of Biomedical Engineering, Rensselaer Polytechnic Institute, Troy, NY (G.D.); and Department of Bioengineering, Northeastern University, Boston, MA (G.D.)
| | - Alejandro P Adam
- From the Department of Molecular and Cellular Physiology (Y.W.L., A.M.L., L.-Y.S., H.A.S., A.P.A., P.A.V., J.J.S.), and Department of Ophthalmology (A.P.A.), Albany Medical College, NY; Department of Biomedical Engineering, Rensselaer Polytechnic Institute, Troy, NY (G.D.); and Department of Bioengineering, Northeastern University, Boston, MA (G.D.)
| | - Peter A Vincent
- From the Department of Molecular and Cellular Physiology (Y.W.L., A.M.L., L.-Y.S., H.A.S., A.P.A., P.A.V., J.J.S.), and Department of Ophthalmology (A.P.A.), Albany Medical College, NY; Department of Biomedical Engineering, Rensselaer Polytechnic Institute, Troy, NY (G.D.); and Department of Bioengineering, Northeastern University, Boston, MA (G.D.)
| | - John J Schwarz
- From the Department of Molecular and Cellular Physiology (Y.W.L., A.M.L., L.-Y.S., H.A.S., A.P.A., P.A.V., J.J.S.), and Department of Ophthalmology (A.P.A.), Albany Medical College, NY; Department of Biomedical Engineering, Rensselaer Polytechnic Institute, Troy, NY (G.D.); and Department of Bioengineering, Northeastern University, Boston, MA (G.D.).
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21
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Zhang S, Zhou R, Li B, Li H, Wang Y, Gu X, Tang L, Wang C, Zhong D, Ge Y, Huo Y, Lin J, Liu XL, Chen JF. Caffeine preferentially protects against oxygen-induced retinopathy. FASEB J 2017; 31:3334-3348. [PMID: 28420694 DOI: 10.1096/fj.201601285r] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Accepted: 04/05/2017] [Indexed: 12/16/2022]
Abstract
Retinopathy of prematurity (ROP) is the leading cause of childhood blindness, but current anti-VEGF therapy is concerned with delayed retinal vasculature, eye, and brain development of preterm infants. The clinical observation of reduced ROP severity in premature infants after caffeine treatment for apnea suggests that caffeine may protect against ROP. Here, we demonstrate that caffeine did not interfere with normal retinal vascularization development but selectively protected against oxygen-induced retinopathy (OIR) in mice. Moreover, caffeine attenuated not only hypoxia-induced pathologic angiogenesis, but also hyperoxia-induced vaso-obliteration, which suggests a novel protection window by caffeine. At the hyperoxic phase, caffeine reduced oxygen-induced neural apoptosis by adenosine A2A receptor (A2AR)-dependent mechanism, as revealed by combined caffeine and A2AR-knockout treatment. At the hypoxic phase, caffeine reduced microglial activation and enhanced tip cell formation by A2AR-dependent and -independent mechanisms, as combined caffeine and A2AR knockout produced additive and nearly full protection against OIR. Together with clinical use of caffeine in neonates, our demonstration of the selective protection against OIR, effective therapeutic window, adenosine receptor mechanisms, and neuroglial involvement provide the direct evidence of the novel effects of caffeine therapy in the prevention and treatment of ROP.-Zhang, S., Zhou, R., Li, B., Li, H., Wang, Y., Gu, X., Tang, L., Wang, C., Zhong, D., Ge, Y., Huo, Y., Lin, J., Liu, X.-L., Chen, J.-F. Caffeine preferentially protects against oxygen-induced retinopathy.
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Affiliation(s)
- Shuya Zhang
- Molecular Neuropharmacology Laboratory, School of Optometry and Ophthalmology and Eye Hospital, Wenzhou Medical University, Wenzhou, China.,State Key Laboratory Cultivation Base and Key Laboratory of Vision Science, Ministry of Health, Wenzhou, China.,Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou, Zhejiang, China
| | - Rong Zhou
- Molecular Neuropharmacology Laboratory, School of Optometry and Ophthalmology and Eye Hospital, Wenzhou Medical University, Wenzhou, China.,State Key Laboratory Cultivation Base and Key Laboratory of Vision Science, Ministry of Health, Wenzhou, China.,Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou, Zhejiang, China
| | - Bo Li
- Molecular Neuropharmacology Laboratory, School of Optometry and Ophthalmology and Eye Hospital, Wenzhou Medical University, Wenzhou, China.,State Key Laboratory Cultivation Base and Key Laboratory of Vision Science, Ministry of Health, Wenzhou, China.,Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou, Zhejiang, China
| | - Haiyan Li
- Molecular Neuropharmacology Laboratory, School of Optometry and Ophthalmology and Eye Hospital, Wenzhou Medical University, Wenzhou, China.,State Key Laboratory Cultivation Base and Key Laboratory of Vision Science, Ministry of Health, Wenzhou, China.,Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou, Zhejiang, China
| | - Yanyan Wang
- Molecular Neuropharmacology Laboratory, School of Optometry and Ophthalmology and Eye Hospital, Wenzhou Medical University, Wenzhou, China.,State Key Laboratory Cultivation Base and Key Laboratory of Vision Science, Ministry of Health, Wenzhou, China.,Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou, Zhejiang, China
| | - Xuejiao Gu
- Molecular Neuropharmacology Laboratory, School of Optometry and Ophthalmology and Eye Hospital, Wenzhou Medical University, Wenzhou, China.,State Key Laboratory Cultivation Base and Key Laboratory of Vision Science, Ministry of Health, Wenzhou, China.,Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou, Zhejiang, China
| | - Lingyun Tang
- Molecular Neuropharmacology Laboratory, School of Optometry and Ophthalmology and Eye Hospital, Wenzhou Medical University, Wenzhou, China.,State Key Laboratory Cultivation Base and Key Laboratory of Vision Science, Ministry of Health, Wenzhou, China.,Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou, Zhejiang, China
| | - Cun Wang
- Molecular Neuropharmacology Laboratory, School of Optometry and Ophthalmology and Eye Hospital, Wenzhou Medical University, Wenzhou, China.,State Key Laboratory Cultivation Base and Key Laboratory of Vision Science, Ministry of Health, Wenzhou, China.,Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou, Zhejiang, China
| | - Dingjuan Zhong
- Molecular Neuropharmacology Laboratory, School of Optometry and Ophthalmology and Eye Hospital, Wenzhou Medical University, Wenzhou, China.,State Key Laboratory Cultivation Base and Key Laboratory of Vision Science, Ministry of Health, Wenzhou, China.,Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou, Zhejiang, China
| | - Yuanyuan Ge
- Molecular Neuropharmacology Laboratory, School of Optometry and Ophthalmology and Eye Hospital, Wenzhou Medical University, Wenzhou, China.,State Key Laboratory Cultivation Base and Key Laboratory of Vision Science, Ministry of Health, Wenzhou, China.,Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou, Zhejiang, China
| | - Yuqing Huo
- Department of Cellular Biology and Anatomy, Vascular Biology Center, Medical College of Georgia, Augusta University, Augusta, Georgia, USA.,Key Laboratory of Chemical Genomics, Drug Discovery Center, Peking University Shenzhen Graduate School, Shenzhen, China
| | - Jing Lin
- Department of Neonatology, Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China.,Department of Pediatrics, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Xiao-Ling Liu
- Molecular Neuropharmacology Laboratory, School of Optometry and Ophthalmology and Eye Hospital, Wenzhou Medical University, Wenzhou, China; .,State Key Laboratory Cultivation Base and Key Laboratory of Vision Science, Ministry of Health, Wenzhou, China.,Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou, Zhejiang, China
| | - Jiang-Fan Chen
- Molecular Neuropharmacology Laboratory, School of Optometry and Ophthalmology and Eye Hospital, Wenzhou Medical University, Wenzhou, China; .,State Key Laboratory Cultivation Base and Key Laboratory of Vision Science, Ministry of Health, Wenzhou, China.,Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou, Zhejiang, China
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22
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Scerri TS, Quaglieri A, Cai C, Zernant J, Matsunami N, Baird L, Scheppke L, Bonelli R, Yannuzzi LA, Friedlander M, Egan CA, Fruttiger M, Leppert M, Allikmets R, Bahlo M. Genome-wide analyses identify common variants associated with macular telangiectasia type 2. Nat Genet 2017; 49:559-567. [DOI: 10.1038/ng.3799] [Citation(s) in RCA: 81] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2016] [Accepted: 01/31/2017] [Indexed: 02/07/2023]
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23
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Chen JF, Zhang S, Zhou R, Lin Z, Cai X, Lin J, Huo Y, Liu X. Adenosine receptors and caffeine in retinopathy of prematurity. Mol Aspects Med 2017; 55:118-125. [PMID: 28088487 DOI: 10.1016/j.mam.2017.01.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2016] [Revised: 12/28/2016] [Accepted: 01/10/2017] [Indexed: 01/26/2023]
Abstract
Retinopathy of prematurity (ROP) is a major cause of childhood blindness in the world and is caused by oxygen-induced damage to the developing retinal vasculature, resulting in hyperoxia-induced vaso-obliteration and subsequent delayed retinal vascularization and hypoxia-induced pathological neovascularization driven by vascular endothelial growth factor (VEGF) signaling pathway in retina. Current anti-VEGF therapy has shown some effective in a clinical trial, but is associated with the unintended effects on delayed eye growth and retinal vasculature development of preterm infants. Notably, cellular responses to hypoxia are characterized by robust increases in extracellular adenosine production and the markedly induced adenosine receptors, which provide a novel target for preferential control of pathological angiogenesis without affecting normal vascular development. Here, we review the experimental evidence in support of adenosine receptor-based therapeutic strategy for ROP, including the aberrant adenosine signaling in oxygen-induced retinopathy and the role of three adenosine receptor subtypes (A1R, A2AR, A2BR) in development and treatment of ROP using oxygen-induced retinopathy models. The clinical and initial animal evidence that implicate the therapeutic effect of caffeine (a non-selective adenosine receptor antagonist) in treatment of ROP are highlighted. Lastly, we discussed the translational potential as well therapeutic advantage of adenosine receptor- and caffeine-based therapy for ROR and possibly other proliferative retinopathy.
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Affiliation(s)
- Jiang-Fan Chen
- Molecular Neuropharmacology Laboratory, School of Optometry and Ophthalmology and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China; State Key Laboratory Cultivation Base and Key Laboratory of Vision Science, Ministry of Health of China, Wenzhou, Zhejiang, China.
| | - Shuya Zhang
- Molecular Neuropharmacology Laboratory, School of Optometry and Ophthalmology and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China; State Key Laboratory Cultivation Base and Key Laboratory of Vision Science, Ministry of Health of China, Wenzhou, Zhejiang, China
| | - Rong Zhou
- State Key Laboratory Cultivation Base and Key Laboratory of Vision Science, Ministry of Health of China, Wenzhou, Zhejiang, China
| | - Zhenlang Lin
- Department of Neonatology, Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Xiaohong Cai
- Department of Neonatology, Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Jing Lin
- Department of Neonatology, Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China; Department of Pediatrics, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Yuqing Huo
- Vascular Biology Center, Department of Cellular Biology and Anatomy, Medical College of Georgia, Georgia Regents University, Augusta, GA 30912, USA; Drug Discovery Center, Key Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Xiaoling Liu
- State Key Laboratory Cultivation Base and Key Laboratory of Vision Science, Ministry of Health of China, Wenzhou, Zhejiang, China
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24
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Sacilotto N, Chouliaras KM, Nikitenko LL, Lu YW, Fritzsche M, Wallace MD, Nornes S, García-Moreno F, Payne S, Bridges E, Liu K, Biggs D, Ratnayaka I, Herbert SP, Molnár Z, Harris AL, Davies B, Bond GL, Bou-Gharios G, Schwarz JJ, De Val S. MEF2 transcription factors are key regulators of sprouting angiogenesis. Genes Dev 2016; 30:2297-2309. [PMID: 27898394 PMCID: PMC5110996 DOI: 10.1101/gad.290619.116] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Accepted: 09/29/2016] [Indexed: 12/24/2022]
Abstract
Angiogenesis, the fundamental process by which new blood vessels form from existing ones, depends on precise spatial and temporal gene expression within specific compartments of the endothelium. However, the molecular links between proangiogenic signals and downstream gene expression remain unclear. During sprouting angiogenesis, the specification of endothelial cells into the tip cells that lead new blood vessel sprouts is coordinated by vascular endothelial growth factor A (VEGFA) and Delta-like ligand 4 (Dll4)/Notch signaling and requires high levels of Notch ligand DLL4. Here, we identify MEF2 transcription factors as crucial regulators of sprouting angiogenesis directly downstream from VEGFA. Through the characterization of a Dll4 enhancer directing expression to endothelial cells at the angiogenic front, we found that MEF2 factors directly transcriptionally activate the expression of Dll4 and many other key genes up-regulated during sprouting angiogenesis in both physiological and tumor vascularization. Unlike ETS-mediated regulation, MEF2-binding motifs are not ubiquitous to all endothelial gene enhancers and promoters but are instead overrepresented around genes associated with sprouting angiogenesis. MEF2 target gene activation is directly linked to VEGFA-induced release of repressive histone deacetylases and concurrent recruitment of the histone acetyltransferase EP300 to MEF2 target gene regulatory elements, thus establishing MEF2 factors as the transcriptional effectors of VEGFA signaling during angiogenesis.
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Affiliation(s)
- Natalia Sacilotto
- Ludwig Institute for Cancer Research Ltd., Nuffield Department of Medicine, University of Oxford, Oxford OX3 7DQ, United Kingdom
| | - Kira M Chouliaras
- Ludwig Institute for Cancer Research Ltd., Nuffield Department of Medicine, University of Oxford, Oxford OX3 7DQ, United Kingdom
| | - Leonid L Nikitenko
- Ludwig Institute for Cancer Research Ltd., Nuffield Department of Medicine, University of Oxford, Oxford OX3 7DQ, United Kingdom
| | - Yao Wei Lu
- Center for Cardiovascular Sciences, Albany Medical College, Albany, New York 12208, USA
| | - Martin Fritzsche
- Ludwig Institute for Cancer Research Ltd., Nuffield Department of Medicine, University of Oxford, Oxford OX3 7DQ, United Kingdom
| | - Marsha D Wallace
- Ludwig Institute for Cancer Research Ltd., Nuffield Department of Medicine, University of Oxford, Oxford OX3 7DQ, United Kingdom
| | - Svanhild Nornes
- Ludwig Institute for Cancer Research Ltd., Nuffield Department of Medicine, University of Oxford, Oxford OX3 7DQ, United Kingdom
| | - Fernando García-Moreno
- Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford OX1 3QX, United Kingdom
| | - Sophie Payne
- Ludwig Institute for Cancer Research Ltd., Nuffield Department of Medicine, University of Oxford, Oxford OX3 7DQ, United Kingdom
| | - Esther Bridges
- Department of Oncology, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford OX3 7LJ, United Kingdom
| | - Ke Liu
- Institute of Aging and Chronic Disease, University of Liverpool, Liverpool L7 8TX, United Kingdom
| | - Daniel Biggs
- The Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, United Kingdom
| | - Indrika Ratnayaka
- Ludwig Institute for Cancer Research Ltd., Nuffield Department of Medicine, University of Oxford, Oxford OX3 7DQ, United Kingdom
| | - Shane P Herbert
- Faculty of Life Sciences, University of Manchester, Manchester M13 9PT, United Kingdom
| | - Zoltán Molnár
- Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford OX1 3QX, United Kingdom
| | - Adrian L Harris
- Department of Oncology, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford OX3 7LJ, United Kingdom
| | - Benjamin Davies
- The Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, United Kingdom
| | - Gareth L Bond
- Ludwig Institute for Cancer Research Ltd., Nuffield Department of Medicine, University of Oxford, Oxford OX3 7DQ, United Kingdom
| | - George Bou-Gharios
- Institute of Aging and Chronic Disease, University of Liverpool, Liverpool L7 8TX, United Kingdom
| | - John J Schwarz
- Center for Cardiovascular Sciences, Albany Medical College, Albany, New York 12208, USA
| | - Sarah De Val
- Ludwig Institute for Cancer Research Ltd., Nuffield Department of Medicine, University of Oxford, Oxford OX3 7DQ, United Kingdom
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25
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Wei Y, Gong J, Xu Z, Duh EJ. Nrf2 promotes reparative angiogenesis through regulation of NADPH oxidase-2 in oxygen-induced retinopathy. Free Radic Biol Med 2016; 99:234-243. [PMID: 27521459 PMCID: PMC8565612 DOI: 10.1016/j.freeradbiomed.2016.08.013] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Revised: 08/01/2016] [Accepted: 08/09/2016] [Indexed: 12/11/2022]
Abstract
Revascularization of ischemic tissue is a highly desirable outcome in multiple diseases, including cardiovascular diseases and ischemic retinopathies. Oxidative stress and inflammation are both known to play a role in suppressing reparative angiogenesis in ischemic disease models including oxygen-induced retinopathy (OIR), but the regulatory molecules governing these pathophysiologic processes in retinal ischemia are largely unknown. Nrf2 is a major stress-response transcription factor that has been implicated in regulating ischemic angiogenesis in the retina and other tissue beds. Using Nrf2-deficient mice, we investigated the effects of Nrf2 in regulating revascularization and modulating the retinal tissue milieu during ischemia. Strikingly, Nrf2's beneficial effect on reparative angiogenesis only became manifested in the later phase of ischemia in OIR, from postnatal day 14 (P14) to P17. This was temporally associated with a reduction in both oxidative stress and inflammatory mediators in wild-type compared to Nrf2-/- mice. Nrf2-/- retinas exhibited an increase in VEGF but also induction of anti-angiogenic Dll4/Notch signaling. NADPH oxidase (NOX), and especially NOX2, is a major pathogenic molecule and a particularly important contributor to oxidative stress in multiple retinal disease processes. Nrf2-/- mice exhibited a significant exacerbation of NOX2 induction in OIR that manifested in the later phases of ischemia. Pharmacologic inhibition of NADPH oxidase abrogated the adverse effect of Nrf2 deficiency on reparative angiogenesis. Taken together, this suggests that Nrf2 is an important regulator of the retinal milieu during tissue ischemia, and that the Nrf2/NOX2 balance may play a critical role in determining the fate of ischemic revascularization.
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MESH Headings
- Adaptor Proteins, Signal Transducing
- Animals
- Animals, Newborn
- Calcium-Binding Proteins
- Gene Expression Regulation
- Intracellular Signaling Peptides and Proteins/genetics
- Intracellular Signaling Peptides and Proteins/metabolism
- Ischemia/genetics
- Ischemia/metabolism
- Ischemia/pathology
- Membrane Proteins/genetics
- Membrane Proteins/metabolism
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- NADPH Oxidase 2/genetics
- NADPH Oxidase 2/metabolism
- NF-E2-Related Factor 2/deficiency
- NF-E2-Related Factor 2/genetics
- Neovascularization, Pathologic/chemically induced
- Neovascularization, Pathologic/genetics
- Neovascularization, Pathologic/metabolism
- Neovascularization, Pathologic/pathology
- Oxidative Stress
- Oxygen/adverse effects
- Receptors, Notch/genetics
- Receptors, Notch/metabolism
- Retina/drug effects
- Retina/metabolism
- Retina/pathology
- Retinitis/chemically induced
- Retinitis/genetics
- Retinitis/metabolism
- Retinitis/pathology
- Signal Transduction
- Vascular Endothelial Growth Factor A/genetics
- Vascular Endothelial Growth Factor A/metabolism
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Affiliation(s)
- Yanhong Wei
- Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Junsong Gong
- Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Zhenhua Xu
- Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Elia J Duh
- Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
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26
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Zhang S, Li H, Li B, Zhong D, Gu X, Tang L, Wang Y, Wang C, Zhou R, Li Y, He Y, Chen M, Huo Y, Liu XL, Chen JF. Adenosine A1 Receptors Selectively Modulate Oxygen-Induced Retinopathy at the Hyperoxic and Hypoxic Phases by Distinct Cellular Mechanisms. Invest Ophthalmol Vis Sci 2016; 56:8108-19. [PMID: 26720463 DOI: 10.1167/iovs.15-17202] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
PURPOSE We critically evaluated the role of the adenosine A1 receptor (A1R) in normal development of retinal vasculature and pathogenesis of retinopathy of prematurity (ROP) by using the A1R knockout (KO) mice and oxygen-induced retinopathy (OIR) model. METHODS Mice deficient in A1Rs and their wild-type (WT) littermates were examined during normal postnatal development or after being subjected to 75% oxygen from postnatal day (P) 7 to P12 and to room air from P12 to P17 (OIR model of ROP). Retinal vascularization was examined by whole-mount fluorescence and cross-sectional hematoxylin-eosin staining. Cellular proliferation, astrocyte and microglial activation, and tip cell function were determined by isolectin staining and immunohistochemistry. Apoptosis was determined by TUNEL assay. RESULTS Genetic deletion of the A1R did not affect normal retinal vascularization during postnatal development with indistinguishable three-layer vascularization patterns in retina between WT and A1R KO mice. In the OIR model, genetic deletion of the A1R resulted in stage-specific effects: reduced hyperoxia-induced retinal vaso-obliteration at P12, but reduced avascular area and attenuated hypoxia-induced intraretinal revascularization without affecting intravitreal neovascularization at P17 and reduced avascular areas in retina at P21. These distinct effects of A1Rs on OIR were associated with A1R control of apoptosis mainly in inner and outer nuclear layers at the vaso-obliterative phase (P12) and the growth of endothelium tip cells at the vasoproliferative phase (P17), without modification of cellular proliferation, astrocytic activation, and tissue inflammation. CONCLUSIONS Adenosine A1 receptor activity is not required for normal postnatal development of retinal vasculature but selectively controls hyperoxia-induced vaso-obliteration and hypoxia-driven revascularization by distinct cellular mechanisms.
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Affiliation(s)
- Shuya Zhang
- Institute of Molecular Medicine, School of Optometry and Ophthalmology and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Haiyan Li
- Institute of Molecular Medicine, School of Optometry and Ophthalmology and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Bo Li
- Institute of Molecular Medicine, School of Optometry and Ophthalmology and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Dingjuan Zhong
- Institute of Molecular Medicine, School of Optometry and Ophthalmology and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Xuejiao Gu
- State Key Laboratory Cultivation Base and Key Laboratory of Vision Science, Ministry of Health, China and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou, Zhejiang, China
| | - Lingyun Tang
- State Key Laboratory Cultivation Base and Key Laboratory of Vision Science, Ministry of Health, China and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou, Zhejiang, China
| | - Yanyan Wang
- State Key Laboratory Cultivation Base and Key Laboratory of Vision Science, Ministry of Health, China and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou, Zhejiang, China
| | - Cun Wang
- State Key Laboratory Cultivation Base and Key Laboratory of Vision Science, Ministry of Health, China and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou, Zhejiang, China
| | - Rong Zhou
- State Key Laboratory Cultivation Base and Key Laboratory of Vision Science, Ministry of Health, China and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou, Zhejiang, China
| | - Yan Li
- Institute of Molecular Medicine, School of Optometry and Ophthalmology and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Yan He
- Institute of Molecular Medicine, School of Optometry and Ophthalmology and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Mozi Chen
- Institute of Molecular Medicine, School of Optometry and Ophthalmology and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Yuqing Huo
- Vascular Biology Center, Department of Cellular Biology and Anatomy, Medical College of Georgia, Georgia Regents University, Augusta, Georgia, United States 4Drug Discovery Center, Key Laboratory of Chemical Genomics, Peking University Shenzhen Graduate S
| | - Xiao-Ling Liu
- State Key Laboratory Cultivation Base and Key Laboratory of Vision Science, Ministry of Health, China and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou, Zhejiang, China
| | - Jiang-Fan Chen
- Institute of Molecular Medicine, School of Optometry and Ophthalmology and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China 5Department of Neurology, Boston University School of Medicine, Boston, Massachusetts, United States
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27
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Jiang Y, Liu H, Liu WJ, Tong HB, Chen CJ, Lin FG, Zhuo YH, Qian XZ, Wang ZB, Wang Y, Zhang P, Jia HL. Endothelial Aquaporin-1 (AQP1) Expression Is Regulated by Transcription Factor Mef2c. Mol Cells 2016; 39:292-8. [PMID: 26923194 PMCID: PMC4844935 DOI: 10.14348/molcells.2016.2223] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2015] [Revised: 11/25/2015] [Accepted: 11/26/2015] [Indexed: 11/30/2022] Open
Abstract
Aquaporin 1 (AQP1) is expressed in most microvasculature endothelial cells and forms water channels that play major roles in a variety of physiologic processes. This study aimed to delineate the transcriptional regulation of AQP1 by Mef2c in endothelial cells. Mef2c cooperated with Sp1 to activate human AQP1 transcription by binding to its proximal promoter in human umbilical cord vein endothelial cells (HUVEC). Over-expression of Mef2c, Sp1, or Mef2c/Sp1 increased HUVEC migration and tube-forming ability, which can be abolished AQP1 knockdown. These data indicate that AQP1 is a direct target of Mef2c in regulating angiogenesis and vasculogenesis of endothelial cells.
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Affiliation(s)
- Yong Jiang
- Medical Examination College, Jilin Medical University, People’s
Republic of China
| | - He Liu
- Medical Examination College, Jilin Medical University, People’s
Republic of China
| | - Wen-jing Liu
- Medical Examination College, Jilin Medical University, People’s
Republic of China
| | - Hai-bin Tong
- Life Science Research Center, Beihua University, Jilin, People’s
Republic of China
| | - Chang-jun Chen
- Medical Examination College, Jilin Medical University, People’s
Republic of China
| | - Fu-gui Lin
- Medical Examination College, Jilin Medical University, People’s
Republic of China
| | - Yan-hang Zhuo
- Medical Examination College, Jilin Medical University, People’s
Republic of China
| | - Xiao-zhen Qian
- Medical Examination College, Jilin Medical University, People’s
Republic of China
| | - Zeng-bin Wang
- Medical Examination College, Jilin Medical University, People’s
Republic of China
| | - Yu Wang
- Medical Examination College, Jilin Medical University, People’s
Republic of China
| | - Peng Zhang
- Medical Examination College, Jilin Medical University, People’s
Republic of China
| | - Hong-liang Jia
- Medical Examination College, Jilin Medical University, People’s
Republic of China
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28
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Cho H, Hartsock MJ, Xu Z, He M, Duh EJ. Monomethyl fumarate promotes Nrf2-dependent neuroprotection in retinal ischemia-reperfusion. J Neuroinflammation 2015; 12:239. [PMID: 26689280 PMCID: PMC4687295 DOI: 10.1186/s12974-015-0452-z] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2015] [Accepted: 12/04/2015] [Indexed: 12/15/2022] Open
Abstract
Background Retinal ischemia results in neuronal degeneration and contributes to the pathogenesis of multiple blinding diseases. Recently, the fumaric acid ester dimethyl fumarate (DMF) has been FDA-approved for the treatment of multiple sclerosis, based on its neuroprotective and anti-inflammatory effects. Its potential role as a neuroprotective agent for retinal diseases has received little attention. In addition, DMF’s mode of action remains elusive, although studies have suggested nuclear factor erythroid 2-related factor 2 (Nrf2) activation as an important mechanism. Here we investigated the neuroprotective role of monomethyl fumarate (MMF), the biologically active metabolite of DMF, in retinal ischemia-reperfusion (I/R) injury, and examined the role of Nrf2 in mediating MMF action. Methods Wild-type C57BL/6J and Nrf2 knockout (KO) mice were subjected to 90 min of retinal ischemia followed by reperfusion. Mice received daily intraperitoneal injection of MMF. Inflammatory gene expression was measured using quantitative reverse transcription PCR (qRT-PCR) at 48 h after I/R injury. Seven days after I/R, qRT-PCR for Nrf2 target gene expression, immunostaining for Müller cell gliosis and cell loss in the ganglion cell layer (GCL), and electroretinography for retinal function were performed. Results The results of this study confirmed that MMF reduces retinal neurodegeneration in an Nrf2-dependent manner. MMF treatment significantly increased the expression of Nrf2-regulated antioxidative genes, suppressed inflammatory gene expression, reduced Müller cell gliosis, decreased neuronal cell loss in the GCL, and improved retinal function measured by electroretinogram (ERG) after retinal I/R injury in wild-type mice. Importantly, these MMF-mediated beneficial effects were not observed in Nrf2 KO mice. Conclusions These results indicate that fumaric acid esters (FAEs) exert a neuronal protective function in the retinal I/R model and further validate Nrf2 modulation as a major mode of action of FAEs. This suggests that DMF and FAEs could be a potential therapeutic agent for activation of the Nrf2 pathway in retinal and possibly systemic diseases. Electronic supplementary material The online version of this article (doi:10.1186/s12974-015-0452-z) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Hongkwan Cho
- Department of Ophthalmology, Johns Hopkins University School of Medicine, 400 N. Broadway, Baltimore, MD, 21287, USA.
| | - Matthew J Hartsock
- Department of Ophthalmology, Johns Hopkins University School of Medicine, 400 N. Broadway, Baltimore, MD, 21287, USA.
| | - Zhenhua Xu
- Department of Ophthalmology, Johns Hopkins University School of Medicine, 400 N. Broadway, Baltimore, MD, 21287, USA.
| | - Meihua He
- Department of Ophthalmology, Johns Hopkins University School of Medicine, 400 N. Broadway, Baltimore, MD, 21287, USA.
| | - Elia J Duh
- Department of Ophthalmology, Johns Hopkins University School of Medicine, 400 N. Broadway, Baltimore, MD, 21287, USA.
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29
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Nrf2 in ischemic neurons promotes retinal vascular regeneration through regulation of semaphorin 6A. Proc Natl Acad Sci U S A 2015; 112:E6927-36. [PMID: 26621751 DOI: 10.1073/pnas.1512683112] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Delayed revascularization of ischemic neural tissue is a major impediment to preservation of function in central nervous system (CNS) diseases including stroke and ischemic retinopathies. Therapeutic strategies allowing rapid revascularization are greatly needed to reduce ischemia-induced cellular damage and suppress harmful pathologic neovascularization. However, key mechanisms governing vascular recovery in ischemic CNS, including regulatory molecules governing the transition from tissue injury to tissue repair, are largely unknown. NF-E2-related factor 2 (Nrf2) is a major stress-response transcription factor well known for its cell-intrinsic cytoprotective function. However, its role in cell-cell crosstalk is less appreciated. Here we report that Nrf2 is highly activated in ischemic retina and promotes revascularization by modulating neurons in their paracrine regulation of endothelial cells. Global Nrf2 deficiency strongly suppresses retinal revascularization and increases pathologic neovascularization in a mouse model of ischemic retinopathy. Conditional knockout studies demonstrate a major role for neuronal Nrf2 in vascular regrowth into avascular retina. Deletion of neuronal Nrf2 results in semaphorin 6A (Sema6A) induction in hypoxic/ischemic retinal ganglion cells in a hypoxia-inducible factor-1 alpha (HIF-1α)-dependent fashion. Sema6A expression increases in avascular inner retina and colocalizes with Nrf2 in human fetal eyes. Extracellular Sema6A leads to dose-dependent suppression of the migratory phenotype of endothelial cells through activation of Notch signaling. Lentiviral-mediated delivery of Sema6A small hairpin RNA (shRNA) abrogates the defective retinal revascularization in Nrf2-deficient mice. Importantly, pharmacologic Nrf2 activation promotes reparative angiogenesis and suppresses pathologic neovascularization. Our findings reveal a unique function of Nrf2 in reprogramming ischemic tissue toward neurovascular repair via Sema6A regulation, providing a potential therapeutic strategy for ischemic retinal and CNS diseases.
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30
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Yu C, Yi J, Yin X, Deng Y, Liao Y, Li X. Correlation of interactions between NOS3 polymorphisms and oxygen therapy with retinopathy of prematurity susceptibility. INTERNATIONAL JOURNAL OF CLINICAL AND EXPERIMENTAL PATHOLOGY 2015; 8:15250-15254. [PMID: 26823875 PMCID: PMC4713661] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 05/12/2015] [Accepted: 06/26/2015] [Indexed: 06/05/2023]
Abstract
AIM This study was aimed to detect the correlation of nitric oxide synthase 3 (NOS3) gene polymorphisms (T-786C and G894T) and retinopathy of prematurity (ROP) susceptibility. Interaction between NOS3 gene polymorphisms and the duration of oxygen therapy was also explored in ROP babies. METHODS Genotypes of NOS3 gene polymorphisms were genotyped by MassArray method. Hardy-Weinberg equilibrium (HWE) was used to calculate the representativeness of the cases and controls. Crossover analysis was utilized to explore the gene environment interactions. Relative risk of ROP was presented by odds ratios (ORs) with corresponding 95% confidence intervals (95% CIs). RESULTS Among the subject features, oxygen therapy had obvious difference between case and control groups (P<0.05). There existed significant association between-786C allele and ROP susceptibility (P=0.049, OR=0.669, 95% CI=0.447-0.999). Genotypes of T-786C polymorphism and genotypes and alleles of G894T polymorphism did not related to the susceptibility of ROP. Interactions were existed between NOS3 gene polymorphisms and oxygen therapy duration. When the duration of oxygen therapy was less than 17 days, both -786CC genotype and 894GT genotype were correlated with ROP susceptibility (P=0.020, OR=0.115, 95% CI=0.014-0.960; P=0.011, OR=0.294, 95% CI=0.100-0.784). CONCLUSION -786C allele might have a protective effect for ROP. Interactions of -786CC and 894GT genotype with oxygen therapy duration (less than 17 days) were both protection factors of ROP.
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Affiliation(s)
- Chunhong Yu
- The Children’s Department of Ophthalmology, The Second Affiliated Hospital of Nanchang UniversityNanchang, Jiangxi, China
| | - Jinglin Yi
- Department of Ophthalmology, The Affiliated Eye Hospital of Nanchang UniversityNanchang, Jiangxi, China
| | - Xiaolong Yin
- The Children’s Department of Ophthalmology, The Second Affiliated Hospital of Nanchang UniversityNanchang, Jiangxi, China
| | - Yan Deng
- The Children’s Department of Ophthalmology, The Second Affiliated Hospital of Nanchang UniversityNanchang, Jiangxi, China
| | - Yujun Liao
- The Children’s Department of Ophthalmology, The Second Affiliated Hospital of Nanchang UniversityNanchang, Jiangxi, China
| | - Xiaobing Li
- Department of Neurology, The First Affiliated Hospital of Nanchang UniversityNanchang, Jiangxi, China
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31
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Zhao YY, Zhao LN, Wang P, Miao YS, Liu YH, Wang ZH, Ma J, Li Z, Li ZQ, Xue YX. Overexpression of miR-18a negatively regulates myocyte enhancer factor 2D to increase the permeability of the blood-tumor barrier via Krüppel-like factor 4-mediated downregulation of zonula occluden-1, claudin-5, and occludin. J Neurosci Res 2015; 93:1891-902. [PMID: 26356851 DOI: 10.1002/jnr.23628] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2015] [Revised: 07/28/2015] [Accepted: 07/28/2015] [Indexed: 01/23/2023]
Abstract
miR-18a represses angiogenesis and tumor evasion by weakening vascular endothelial growth factor and transforming growth factor-β signaling to prolong the survival of glioma patients, although it is thought to be an oncogene. This study investigates the potential effects of miR-18a on the permeability of the blood-tumor barrier (BTB) and its possible molecular mechanisms. An in vitro BTB model was successfully established. The endogenous expression of miR-18a in glioma vascular endothelial cells (GECs) was significantly lower than that in normal vascular ECs, and the overexpression of miR-18a significantly increased the permeability of the BTB as well as downregulating the mRNA and protein expressions of tight junction-related proteins zonula occluden-1 (ZO-1), claudin-5, and occludin in GECs. Dual luciferase reporter assays revealed that miR-18a bound to the 3'-untranslated region (3'UTR) of myocyte enhancer factor 2D (MEF2D). The overexpression of both miR-18a and MEF2D with the 3'UTR significantly weakened the effect caused by miR-18a of decreasing the mRNA and protein expressions of ZO-1, claudin-5 and occludin and of increasing the permeability of the BTB. Chromatin immunoprecipitation showed that MEF2D could directly bind to KLF4 promoter. This study shows that miR-18a targets and negatively regulates MEF2D, which further regulates tight junction-related proteins ZO-1, claudin-5, and occludin through transactivation of KLF4 and, finally, changes the permeability of the BTB. MiR-18a should garner growing attention because it might serve as a potential target in opening the BTB and providing a new strategy for the treatment of gliomas.
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Affiliation(s)
- Ying-Yu Zhao
- Department of Neurobiology, College of Basic Medicine, China Medical University, Shenyang, China.,Institute of Pathology and Pathophysiology, China Medical University, Shenyang, China
| | - Li-Ni Zhao
- Department of Neurobiology, College of Basic Medicine, China Medical University, Shenyang, China.,Institute of Pathology and Pathophysiology, China Medical University, Shenyang, China
| | - Ping Wang
- Department of Neurobiology, College of Basic Medicine, China Medical University, Shenyang, China.,Institute of Pathology and Pathophysiology, China Medical University, Shenyang, China
| | - Yin-Sha Miao
- Department of Neurobiology, College of Basic Medicine, China Medical University, Shenyang, China.,Institute of Pathology and Pathophysiology, China Medical University, Shenyang, China
| | - Yun-Hui Liu
- Department of Neurosurgery, Shengjing Hospital of China Medical University, Shenyang, China
| | - Zhen-Hua Wang
- Department of Physiology, College of Basic Medicine, China Medical University, Shenyang, China
| | - Jun Ma
- Department of Neurobiology, College of Basic Medicine, China Medical University, Shenyang, China.,Institute of Pathology and Pathophysiology, China Medical University, Shenyang, China
| | - Zhen Li
- Department of Neurosurgery, Shengjing Hospital of China Medical University, Shenyang, China
| | - Zhi-Qing Li
- Department of Neurobiology, College of Basic Medicine, China Medical University, Shenyang, China.,Institute of Pathology and Pathophysiology, China Medical University, Shenyang, China
| | - Yi-Xue Xue
- Department of Neurobiology, College of Basic Medicine, China Medical University, Shenyang, China.,Institute of Pathology and Pathophysiology, China Medical University, Shenyang, China
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Kim JD, Lee A, Choi J, Park Y, Kang H, Chang W, Lee MS, Kim J. Epigenetic modulation as a therapeutic approach for pulmonary arterial hypertension. Exp Mol Med 2015; 47:e175. [PMID: 26228095 PMCID: PMC4525299 DOI: 10.1038/emm.2015.45] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Pulmonary arterial hypertension (PAH) is a rare but progressive and currently incurable disease, which is characterized by vascular remodeling in association with muscularization of the arterioles, medial thickening and plexiform lesion formation. Despite our advanced understanding of the pathogenesis of PAH and the recent therapeutic advances, PAH still remains a fatal disease. In addition, the susceptibility to PAH has not yet been adequately explained. Much evidence points to the involvement of epigenetic changes in the pathogenesis of a number of human diseases including cancer, peripheral hypertension and asthma. The knowledge gained from the epigenetic study of various human diseases can also be applied to PAH. Thus, the pursuit of novel therapeutic targets via understanding the epigenetic alterations involved in the pathogenesis of PAH, such as DNA methylation, histone modification and microRNA, might be an attractive therapeutic avenue for the development of a novel and more effective treatment. This review provides a general overview of the current advances in epigenetics associated with PAH, and discusses the potential for improved treatment through understanding the role of epigenetics in the development of PAH.
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Affiliation(s)
- Jun-Dae Kim
- Department of Internal Medicine, Yale Cardiovascular Research Center, Section of Cardiovascular Medicine, Yale University School of Medicine, New Haven, CT, USA
| | - Aram Lee
- Department of Life Systems, Sookmyung Women's University, Seoul, Korea
| | - Jihea Choi
- Department of Life Systems, Sookmyung Women's University, Seoul, Korea
| | - Youngsook Park
- Department of Life Systems, Sookmyung Women's University, Seoul, Korea
| | - Hyesoo Kang
- Department of Life Systems, Sookmyung Women's University, Seoul, Korea
| | - Woochul Chang
- Department of Biology Education, College of Education, Pusan National University, Busan, Korea
| | - Myeong-Sok Lee
- Department of Life Systems, Sookmyung Women's University, Seoul, Korea
| | - Jongmin Kim
- Department of Life Systems, Sookmyung Women's University, Seoul, Korea
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Xu Z, Yoshida T, Wu L, Maiti D, Cebotaru L, Duh EJ. Transcription factor MEF2C suppresses endothelial cell inflammation via regulation of NF-κB and KLF2. J Cell Physiol 2015; 230:1310-20. [PMID: 25474999 DOI: 10.1002/jcp.24870] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Accepted: 11/11/2014] [Indexed: 12/18/2022]
Abstract
Endothelial cells play a major role in the initiation and perpetuation of the inflammatory process in health and disease, including their pivotal role in leukocyte recruitment. The role of pro-inflammatory transcription factors in this process has been well-described, including NF-κB. However, much less is known regarding transcription factors that play an anti-inflammatory role in endothelial cells. Myocyte enhancer factor 2 C (MEF2C) is a transcription factor known to regulate angiogenesis in endothelial cells. Here, we report that MEF2C plays a critical function as an inhibitor of endothelial cell inflammation. Tumor necrosis factor (TNF)-α inhibited MEF2C expression in endothelial cells. Knockdown of MEF2C in endothelial cells resulted in the upregulation of pro-inflammatory molecules and stimulated leukocyte adhesion to endothelial cells. MEF2C knockdown also resulted in NF-κB activation in endothelial cells. Conversely, MEF2C overexpression by adenovirus significantly repressed TNF-α induction of pro-inflammatory molecules, activation of NF-κB, and leukocyte adhesion to endothelial cells. This inhibition of leukocyte adhesion by MEF2C was partially mediated by induction of KLF2. In mice, lipopolysaccharide (LPS)-induced leukocyte adhesion to the retinal vasculature was significantly increased by endothelial cell-specific ablation of MEF2C. Taken together, these results demonstrate that MEF2C is a novel negative regulator of inflammation in endothelial cells and may represent a therapeutic target for vascular inflammation.
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Affiliation(s)
- Zhenhua Xu
- Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, Maryland
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Artham S, Fouda AY, El-Remessy AB, Fagan SC. Vascular protective effects of Angiotensin Receptor Blockers: Beyond Blood pressure. ACTA ACUST UNITED AC 2015; 2. [PMID: 26317114 DOI: 10.14800/rci.774] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Sandeep Artham
- Program in Clinical and Experimental Therapeutics, University of Georgia College of Pharmacy, and Georgia Regents University, Charlie Norwood VA Medical Center, Augusta, GA, USA
| | - Abdelrahman Y Fouda
- Program in Clinical and Experimental Therapeutics, University of Georgia College of Pharmacy, and Georgia Regents University, Charlie Norwood VA Medical Center, Augusta, GA, USA
| | - Azza B El-Remessy
- Program in Clinical and Experimental Therapeutics, University of Georgia College of Pharmacy, and Georgia Regents University, Charlie Norwood VA Medical Center, Augusta, GA, USA
| | - Susan C Fagan
- Program in Clinical and Experimental Therapeutics, University of Georgia College of Pharmacy, and Georgia Regents University, Charlie Norwood VA Medical Center, Augusta, GA, USA
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Xu Z, Cho H, Hartsock MJ, Mitchell KL, Gong J, Wu L, Wei Y, Wang S, Thimmulappa RK, Sporn MB, Biswal S, Welsbie DS, Duh EJ. Neuroprotective role of Nrf2 for retinal ganglion cells in ischemia-reperfusion. J Neurochem 2015; 133:233-41. [PMID: 25683606 DOI: 10.1111/jnc.13064] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2014] [Revised: 02/05/2015] [Accepted: 02/09/2015] [Indexed: 01/11/2023]
Abstract
Retinal ischemia plays a critical role in multiple vision-threatening diseases and leads to death of retinal neurons, particularly ganglion cells. Oxidative stress plays an important role in this ganglion cell loss. Nrf2 (NF-E2-related factor 2) is a major regulator of the antioxidant response, and its role in the retina is increasingly appreciated. We investigated the potential retinal neuroprotective function of Nrf2 after ischemia-reperfusion (I/R) injury. In an experimental model of retinal I/R, Nrf2 knockout mice exhibited much greater loss of neuronal cells in the ganglion cell layer than wild-type mice. Primary retinal ganglion cells isolated from Nrf2 knockout mice exhibited decreased cell viability compared to wild-type retinal ganglion cells, demonstrating the cell-intrinsic protective role of Nrf2. The retinal neuronal cell line 661W exhibited reduced cell viability following siRNA-mediated knockdown of Nrf2 under conditions of oxidative stress, and this was associated with exacerbation of increase in reactive oxygen species. The synthetic triterpenoid CDDO-Im (2-Cyano-3,12-dioxooleana-1,9-dien-28-imidazolide), a potent Nrf2 activator, inhibited reactive oxygen species increase in cultured 661W under oxidative stress conditions and increased neuronal cell survival after I/R injury in wild-type, but not Nrf2 knockout mice. Our findings indicate that Nrf2 exhibits a retinal neuroprotective function in I/R and suggest that pharmacologic activation of Nrf2 could be a therapeutic strategy. Oxidative stress is thought to be an important mediator of retinal ganglion cell death in ischemia-reperfusion injury. We found that the transcription factor NF-E2-related factor 2 (Nrf2), a major regulator of oxidative stress, is an important endogenous neuroprotective molecule in retinal ganglion cells in ischemia-reperfusion, exerting a cell-autonomous protective effect. The triterpenoid 2-Cyano-3,12-dioxooleana-1,9-dien-28-imidazolide (CDDO-Im) reduces neurodegeneration following ischemia-reperfusion in an Nrf2-dependent fashion. This suggests that Nrf2-activating drugs including triterpenoids could be a therapeutic strategy for retinal neuroprotection.
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Affiliation(s)
- Zhenhua Xu
- Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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Shanab AY, Elshaer SL, El-Azab MF, Soliman S, Sabbineni H, Matragoon S, Fagan SC, El-Remessy AB. Candesartan stimulates reparative angiogenesis in ischemic retinopathy model: role of hemeoxygenase-1 (HO-1). Angiogenesis 2014; 18:137-50. [PMID: 25420481 DOI: 10.1007/s10456-014-9451-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2014] [Accepted: 11/12/2014] [Indexed: 02/06/2023]
Abstract
Ischemic diseases such as stroke and proliferative retinopathy are characterized by hypoxia-driven release of angiogenic factors such as vascular endothelial growth factor (VEGF). However, revascularization of the ischemic areas is inadequate, resulting in impaired neuro-vascular function. We aim to examine the vascular protective effects of candesartan, an angiotensin receptor blocker, in an ischemic retinopathy mouse model. Vascular density, number of tip cells, and perfusions of capillaries were assessed. Activation of Muller glial cells and levels of peroxynitrite, VEGF, VEGFR2, inducible nitric oxide synthase, hemeoxygenase-1 (HO-1) were assessed. Proangiogenic effects of candesartan were examined in human endothelial cells (EC) that were cultured in normoxia or hypoxia and transduced with siRNA against HO-1. Candesartan (1 mg/kg) and (10 mg/kg) decreased hypoxia-induced neovascularization by 67 and 70%, respectively. Candesartan (10 mg/kg) significantly stimulated the number of tip cells and physiological revascularization of the central retina (45%) compared with untreated pups. The effects of candesartan coincided with reduction of hypoxia-induced Muller glial activation, iNOS expression and restoration of HO-1 expression with no significant change in VEGF levels. In vitro, silencing HO-1 expression blunted the ability of candesartan to induce VEGF expression under normoxia and VEGFR2 activation and angiogenic response under both normoxia and hypoxia. These findings suggest that candesartan improved reparative angiogenesis and hence prevented pathological angiogenesis by modulating HO-1 and iNOS levels in ischemic retinopathy. HO-1 is required for VEGFR2 activation and proangiogenic action of candesartan in EC. Candesartan, an FDA-approved drug, could be repurposed as a potential therapeutic agent for the treatment of ischemic diseases.
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Affiliation(s)
- Ahmed Y Shanab
- Program in Clinical and Experimental Therapeutics, College of Pharmacy, University of Georgia, Augusta, GA, 30912, USA
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Kim J, Hwangbo C, Hu X, Kang Y, Papangeli I, Mehrotra D, Park H, Ju H, McLean DL, Comhair SA, Erzurum SC, Chun HJ. Restoration of impaired endothelial myocyte enhancer factor 2 function rescues pulmonary arterial hypertension. Circulation 2014; 131:190-9. [PMID: 25336633 DOI: 10.1161/circulationaha.114.013339] [Citation(s) in RCA: 86] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
BACKGROUND Pulmonary arterial hypertension (PAH) is a progressive disease of the pulmonary arterioles, characterized by increased pulmonary arterial pressure and right ventricular failure. The cause of PAH is complex, but aberrant proliferation of the pulmonary artery endothelial cells (PAECs) and pulmonary artery smooth muscle cells is thought to play an important role in its pathogenesis. Understanding the mechanisms of transcriptional gene regulation involved in pulmonary vascular homeostasis can provide key insights into potential therapeutic strategies. METHODS AND RESULTS We demonstrate that the activity of the transcription factor myocyte enhancer factor 2 (MEF2) is significantly impaired in the PAECs derived from subjects with PAH. We identified MEF2 as the key cis-acting factor that regulates expression of a number of transcriptional targets involved in pulmonary vascular homeostasis, including microRNAs 424 and 503, connexins 37, and 40, and Krűppel Like Factors 2 and 4, which were found to be significantly decreased in PAH PAECs. The impaired MEF2 activity in PAH PAECs was mediated by excess nuclear accumulation of 2 class IIa histone deacetylases (HDACs) that inhibit its function, namely HDAC4 and HDAC5. Selective, pharmacological inhibition of class IIa HDACs led to restoration of MEF2 activity in PAECs, as demonstrated by increased expression of its transcriptional targets, decreased cell migration and proliferation, and rescue of experimental pulmonary hypertension models. CONCLUSIONS Our results demonstrate that strategies to augment MEF2 activity hold potential therapeutic value in PAH. Moreover, we identify selective HDAC IIa inhibition as a viable alternative approach to avoid the potential adverse effects of broad spectrum HDAC inhibition in PAH.
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Affiliation(s)
- Jongmin Kim
- From the Yale Cardiovascular Research Center, Section of Cardiovascular Medicine, Yale University School of Medicine, New Haven, CT (J.K., C.H., X.H., Y.K., I.P., D.M., H.P., H.J., D.L.M., H.J.C.); the Department of Life Systems, Sookmyung Women's University, Seoul, Korea (J.K.); and the Department of Pathobiology, The Lerner Institute, The Cleveland Clinic Foundation, Cleveland, OH (S.A.C., S.C.E.)
| | - Cheol Hwangbo
- From the Yale Cardiovascular Research Center, Section of Cardiovascular Medicine, Yale University School of Medicine, New Haven, CT (J.K., C.H., X.H., Y.K., I.P., D.M., H.P., H.J., D.L.M., H.J.C.); the Department of Life Systems, Sookmyung Women's University, Seoul, Korea (J.K.); and the Department of Pathobiology, The Lerner Institute, The Cleveland Clinic Foundation, Cleveland, OH (S.A.C., S.C.E.)
| | - Xiaoyue Hu
- From the Yale Cardiovascular Research Center, Section of Cardiovascular Medicine, Yale University School of Medicine, New Haven, CT (J.K., C.H., X.H., Y.K., I.P., D.M., H.P., H.J., D.L.M., H.J.C.); the Department of Life Systems, Sookmyung Women's University, Seoul, Korea (J.K.); and the Department of Pathobiology, The Lerner Institute, The Cleveland Clinic Foundation, Cleveland, OH (S.A.C., S.C.E.)
| | - Yujung Kang
- From the Yale Cardiovascular Research Center, Section of Cardiovascular Medicine, Yale University School of Medicine, New Haven, CT (J.K., C.H., X.H., Y.K., I.P., D.M., H.P., H.J., D.L.M., H.J.C.); the Department of Life Systems, Sookmyung Women's University, Seoul, Korea (J.K.); and the Department of Pathobiology, The Lerner Institute, The Cleveland Clinic Foundation, Cleveland, OH (S.A.C., S.C.E.)
| | - Irinna Papangeli
- From the Yale Cardiovascular Research Center, Section of Cardiovascular Medicine, Yale University School of Medicine, New Haven, CT (J.K., C.H., X.H., Y.K., I.P., D.M., H.P., H.J., D.L.M., H.J.C.); the Department of Life Systems, Sookmyung Women's University, Seoul, Korea (J.K.); and the Department of Pathobiology, The Lerner Institute, The Cleveland Clinic Foundation, Cleveland, OH (S.A.C., S.C.E.)
| | - Devi Mehrotra
- From the Yale Cardiovascular Research Center, Section of Cardiovascular Medicine, Yale University School of Medicine, New Haven, CT (J.K., C.H., X.H., Y.K., I.P., D.M., H.P., H.J., D.L.M., H.J.C.); the Department of Life Systems, Sookmyung Women's University, Seoul, Korea (J.K.); and the Department of Pathobiology, The Lerner Institute, The Cleveland Clinic Foundation, Cleveland, OH (S.A.C., S.C.E.)
| | - Hyekyung Park
- From the Yale Cardiovascular Research Center, Section of Cardiovascular Medicine, Yale University School of Medicine, New Haven, CT (J.K., C.H., X.H., Y.K., I.P., D.M., H.P., H.J., D.L.M., H.J.C.); the Department of Life Systems, Sookmyung Women's University, Seoul, Korea (J.K.); and the Department of Pathobiology, The Lerner Institute, The Cleveland Clinic Foundation, Cleveland, OH (S.A.C., S.C.E.)
| | - Hyekyung Ju
- From the Yale Cardiovascular Research Center, Section of Cardiovascular Medicine, Yale University School of Medicine, New Haven, CT (J.K., C.H., X.H., Y.K., I.P., D.M., H.P., H.J., D.L.M., H.J.C.); the Department of Life Systems, Sookmyung Women's University, Seoul, Korea (J.K.); and the Department of Pathobiology, The Lerner Institute, The Cleveland Clinic Foundation, Cleveland, OH (S.A.C., S.C.E.)
| | - Danielle L McLean
- From the Yale Cardiovascular Research Center, Section of Cardiovascular Medicine, Yale University School of Medicine, New Haven, CT (J.K., C.H., X.H., Y.K., I.P., D.M., H.P., H.J., D.L.M., H.J.C.); the Department of Life Systems, Sookmyung Women's University, Seoul, Korea (J.K.); and the Department of Pathobiology, The Lerner Institute, The Cleveland Clinic Foundation, Cleveland, OH (S.A.C., S.C.E.)
| | - Suzy A Comhair
- From the Yale Cardiovascular Research Center, Section of Cardiovascular Medicine, Yale University School of Medicine, New Haven, CT (J.K., C.H., X.H., Y.K., I.P., D.M., H.P., H.J., D.L.M., H.J.C.); the Department of Life Systems, Sookmyung Women's University, Seoul, Korea (J.K.); and the Department of Pathobiology, The Lerner Institute, The Cleveland Clinic Foundation, Cleveland, OH (S.A.C., S.C.E.)
| | - Serpil C Erzurum
- From the Yale Cardiovascular Research Center, Section of Cardiovascular Medicine, Yale University School of Medicine, New Haven, CT (J.K., C.H., X.H., Y.K., I.P., D.M., H.P., H.J., D.L.M., H.J.C.); the Department of Life Systems, Sookmyung Women's University, Seoul, Korea (J.K.); and the Department of Pathobiology, The Lerner Institute, The Cleveland Clinic Foundation, Cleveland, OH (S.A.C., S.C.E.)
| | - Hyung J Chun
- From the Yale Cardiovascular Research Center, Section of Cardiovascular Medicine, Yale University School of Medicine, New Haven, CT (J.K., C.H., X.H., Y.K., I.P., D.M., H.P., H.J., D.L.M., H.J.C.); the Department of Life Systems, Sookmyung Women's University, Seoul, Korea (J.K.); and the Department of Pathobiology, The Lerner Institute, The Cleveland Clinic Foundation, Cleveland, OH (S.A.C., S.C.E.).
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Sturtzel C, Testori J, Schweighofer B, Bilban M, Hofer E. The transcription factor MEF2C negatively controls angiogenic sprouting of endothelial cells depending on oxygen. PLoS One 2014; 9:e101521. [PMID: 24988463 PMCID: PMC4079651 DOI: 10.1371/journal.pone.0101521] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2014] [Accepted: 06/09/2014] [Indexed: 11/18/2022] Open
Abstract
The MADS box transcription factor MEF2C has been detected by us to be upregulated by the angiogenic factors VEGF-A and bFGF in endothelial cells. We have here investigated its potential role for angiogenesis. MEF2C was surprisingly found to strongly inhibit angiogenic sprouting, whereas a dominant negative mutant rather induced sprouting. The factor mainly affected migratory processes of endothelial cells, but not proliferation. In gene profiling experiments we delineated the alpha-2-macroglobulin gene to be highly upregulated by MEF2C. Further data confirmed that MEF2C in endothelial cells indeed induces alpha-2-macroglobulin mRNA as well as the secretion of alpha-2-macroglobulin and that conditioned supernatants of cells overexpressing MEF2C inhibit sprouting. Alpha-2-macroglobulin mediates, at least to a large extent, the inhibitory effects of MEF2C as is shown by knockdown of alpha-2-macroglobulin mRNA by lentiviral shRNA expression which reduces the inhibitory effect. However, under hypoxic conditions the VEGF-A/bFGF-mediated upregulation of MEF2C is reduced and the production of alpha-2-macroglobulin largely abolished. Taken together, this suggests that the MEF2C/alpha-2-macroglobulin axis functions in endothelial cells as a negative feed-back mechanism that adapts sprouting activity to the oxygen concentration thus diminishing inappropriate and excess angiogenesis.
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Affiliation(s)
- Caterina Sturtzel
- Department of Vascular Biology and Thrombosis Research, Center for Physiology and Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Julia Testori
- Department of Vascular Biology and Thrombosis Research, Center for Physiology and Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Bernhard Schweighofer
- Department of Vascular Biology and Thrombosis Research, Center for Physiology and Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Martin Bilban
- Department of Laboratory Medicine, Medical University of Vienna, Vienna, Austria
| | - Erhard Hofer
- Department of Vascular Biology and Thrombosis Research, Center for Physiology and Pharmacology, Medical University of Vienna, Vienna, Austria
- * E-mail:
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Nrf2 acts cell-autonomously in endothelium to regulate tip cell formation and vascular branching. Proc Natl Acad Sci U S A 2013; 110:E3910-8. [PMID: 24062466 DOI: 10.1073/pnas.1309276110] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Angiogenesis, in which new blood vessels form via endothelial cell (EC) sprouting from existing vessels, is a critical event in embryonic development and multiple disease processes. Many insights have been made into key EC receptors and ligands/growth factors that govern sprouting angiogenesis, but intracellular molecular mechanisms of this process are not well understood. NF-E2-related factor 2 (Nrf2) is a transcription factor well-known for regulating the stress response in multiple pathologic settings, but its role in development is less appreciated. Here, we show that Nrf2 is increased and activated during vascular development. Global deletion of Nrf2 resulted in reduction of vascular density as well as EC sprouting. This was also observed with specific deletion of Nrf2 in ECs, but not with deletion of Nrf2 in the surrounding nonvascular tissue. Nrf2 deletion resulted in increased delta-like ligand 4 (Dll4) expression and Notch activity in ECs. Blockade of Dll4 or Notch signaling restored the vascular phenotype in Nrf2 KOs. Constitutive activation of endothelial Nrf2 enhanced EC sprouting and vascularization by suppression of Dll4/Notch signaling in vivo and in vitro. Nrf2 activation in ECs suppressed Dll4 expression under normoxia and hypoxia and inhibited Dll4-induced Notch signaling. Activation of Nrf2 blocked VEGF induction of VEGFR2-PI3K/Akt and downregulated HIF-2α in ECs, which may serve as important mechanisms for Nrf2 inhibition of Dll4 and Notch signaling. Our data reveal a function for Nrf2 in promoting the angiogenic sprouting phenotype in vascular ECs.
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Zhang W, Zhang X, Lu H, Matsukura M, Zhao J, Shinohara M. Silencing heme oxygenase-1 gene expression in retinal pigment epithelial cells inhibits proliferation, migration and tube formation of cocultured endothelial cells. Biochem Biophys Res Commun 2013; 434:492-7. [PMID: 23583371 DOI: 10.1016/j.bbrc.2013.03.101] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2013] [Accepted: 03/24/2013] [Indexed: 10/26/2022]
Abstract
Heme oxygenase-1 (HO-1) plays an important role in the vasculature and in the angiogenesis of tumors, wounds and other environments. Retinal pigment epithelial (RPE) cells and choroidal endothelial cells (CECs) are the main cells involved in choroidal neovascularization (CNV), a process in which hypoxia plays an important role. Our aim was to evaluate the role of human RPE-cell HO-1 in the angiogenic activities of cocultured endothelial cells under hypoxia. Small interfering RNA (siRNA) for HO-1 was transfected into human RPE cell line ARPE-19, and zinc protoporphyrin (ZnPP) was used to inhibit HO-1 activity. Knockdown of HO-1 expression and inhibition of HO-1 activity resulted in potent reduction of the expression of vascular endothelial growth factor (VEGF) under hypoxia. Furthermore, knockdown of HO-1 suppressed the proliferation, migration and tube formation of cocultured endothelial cells. These findings indicated that HO-1 might have an angiogenic effect in CNV through modulation of VEGF expression and might be a potential target for treating CNV.
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Affiliation(s)
- Wenjie Zhang
- Ophthalmology Hospital, The First Affiliated Hospital of Harbin Medical University, 23 Youzheng Street, Harbin 150001, China
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