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Chen X, Sun X, Ge Y, Zhou X, Chen JF. Targeting adenosine A 2A receptors for early intervention of retinopathy of prematurity. Purinergic Signal 2024:10.1007/s11302-024-09986-x. [PMID: 38329708 DOI: 10.1007/s11302-024-09986-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Accepted: 01/16/2024] [Indexed: 02/09/2024] Open
Abstract
Retinopathy of prematurity (ROP) continues to pose a significant threat to the vision of numerous children worldwide, primarily owing to the increased survival rates of premature infants. The pathologies of ROP are mainly linked to impaired vascularization as a result of hyperoxia, leading to subsequent neovascularization. Existing treatments, including anti-vascular endothelial growth factor (VEGF) therapies, have thus far been limited to addressing pathological angiogenesis at advanced ROP stages, inevitably leading to adverse side effects. Intervention to promote physiological angiogenesis during the initial stages could hold the potential to prevent ROP. Adenosine A2A receptors (A2AR) have been identified in various ocular cell types, exhibiting distinct densities and functionally intricate connections with oxygen metabolism. In this review, we discuss experimental evidence that strongly underscores the pivotal role of A2AR in ROP. In particular, A2AR blockade may represent an effective treatment strategy, mitigating retinal vascular loss by reversing hyperoxia-mediated cellular proliferation inhibition and curtailing hypoxia-mediated neovascularization in oxygen-induced retinopathy (OIR). These effects stem from the interplay of endothelium, neuronal and glial cells, and novel molecular pathways (notably promoting TGF-β signaling) at the hyperoxia phase. We propose that pharmacological targeting of A2AR signaling may confer an early intervention for ROP with distinct therapeutic benefits and mechanisms than the anti-VEGF therapy.
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Affiliation(s)
- Xuhao Chen
- The Molecular Neuropharmacology Laboratory and the Eye-Brain Research Center, The State Key Laboratory of Ophthalmology, Optometry and Vision Science, Wenzhou Medical University, Wenzhou, China
| | - Xiaoting Sun
- The Molecular Neuropharmacology Laboratory and the Eye-Brain Research Center, The State Key Laboratory of Ophthalmology, Optometry and Vision Science, Wenzhou Medical University, Wenzhou, China
| | - Yuanyuan Ge
- The Molecular Neuropharmacology Laboratory and the Eye-Brain Research Center, The State Key Laboratory of Ophthalmology, Optometry and Vision Science, Wenzhou Medical University, Wenzhou, China
| | - Xuzhao Zhou
- The Molecular Neuropharmacology Laboratory and the Eye-Brain Research Center, The State Key Laboratory of Ophthalmology, Optometry and Vision Science, Wenzhou Medical University, Wenzhou, China.
| | - Jiang-Fan Chen
- The Molecular Neuropharmacology Laboratory and the Eye-Brain Research Center, The State Key Laboratory of Ophthalmology, Optometry and Vision Science, Wenzhou Medical University, Wenzhou, China.
- Oujiang Laboratory (Zhejiang Lab for Regenerative Medicine, Vision and Brain Health), Wenzhou, China.
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2
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Abstract
Retinopathy of prematurity (ROP) is a complex disease involving development of the neural retina, ocular circulations, and other organ systems of the premature infant. The external stresses of the ex utero environment also influence the pathophysiology of ROP through interactions among retinal neural, vascular, and glial cells. There is variability among individual infants and presentations of the disease throughout the world, making ROP challenging to study. The methods used include representative animal models, cell culture, and clinical studies. This article describes the impact of maternal-fetal interactions; stresses that the preterm infant experiences; and biologic pathways of interest, including growth factor effects and cell-cell interactions, on the complex pathophysiology of ROP phenotypes in developed and emerging countries.
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3
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Sorenson CM, Song YS, Zaitoun IS, Wang S, Hanna BA, Darjatmoko SR, Gurel Z, Fisk DL, McDowell CM, McAdams RM, Sheibani N. Caffeine Inhibits Choroidal Neovascularization Through Mitigation of Inflammatory and Angiogenesis Activities. Front Cell Dev Biol 2021; 9:737426. [PMID: 34722519 PMCID: PMC8551619 DOI: 10.3389/fcell.2021.737426] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Accepted: 09/13/2021] [Indexed: 12/20/2022] Open
Abstract
Adenosine receptors (AR) are widely expressed in a variety of tissues including the retina and brain. They are involved in adenosine-mediated immune responses underlying the onset and progression of neurodegenerative diseases. The expression of AR has been previously demonstrated in some retinal cells including endothelial cells and retinal pigment epithelial cells, but their expression in the choroid and choroidal cells remains unknown. Caffeine is a widely consumed AR antagonist that can influence inflammation and vascular cell function. It has established roles in the treatment of neonatal sleep apnea, acute migraine, and post lumbar puncture headache as well as the neurodegenerative diseases such as Parkinson and Alzheimer. More recently, AR antagonism with caffeine has been shown to protect preterm infants from ischemic retinopathy and retinal neovascularization. However, whether caffeine impacts the development and progression of ocular age-related diseases including neovascular age-related macular degermation remains unknown. Here, we examined the expression of AR in retinal and choroidal tissues and cells. We showed that antagonism of AR with caffeine or istradefylline decreased sprouting of thoracic aorta and choroid/retinal pigment epithelium explants in ex vivo cultures, consistent with caffeine's ability to inhibit endothelial cell migration in culture. In vivo studies also demonstrated the efficacy of caffeine in inhibition of choroidal neovascularization and mononuclear phagocyte recruitment to the laser lesion sites. Istradefylline, a specific AR 2A antagonist, also decreased choroidal neovascularization. Collectively, our studies demonstrate an important role for expression of AR in the choroid whose antagonism mitigate choroidal inflammatory and angiogenesis activities.
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Affiliation(s)
- Christine M Sorenson
- Department of Pediatrics, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States.,McPherson Eye Research Institute, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States
| | - Yong-Seok Song
- Department of Ophthalmology and Visual Sciences, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States
| | - Ismail S Zaitoun
- McPherson Eye Research Institute, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States.,Department of Ophthalmology and Visual Sciences, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States
| | - Shoujian Wang
- Department of Ophthalmology and Visual Sciences, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States
| | - Barbara A Hanna
- Department of Pediatrics, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States
| | - Soesiawati R Darjatmoko
- McPherson Eye Research Institute, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States.,Department of Ophthalmology and Visual Sciences, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States
| | - Zafer Gurel
- Department of Human Oncology, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States
| | - Debra L Fisk
- Department of Ophthalmology and Visual Sciences, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States
| | - Colleen M McDowell
- McPherson Eye Research Institute, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States.,Department of Ophthalmology and Visual Sciences, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States
| | - Ryan M McAdams
- Department of Pediatrics, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States
| | - Nader Sheibani
- McPherson Eye Research Institute, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States.,Department of Ophthalmology and Visual Sciences, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States.,Department of Cell and Regenerative Biology, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States.,Department of Biomedical Engineering, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States
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4
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Santiago AR, Madeira MH, Boia R, Aires ID, Rodrigues-Neves AC, Santos PF, Ambrósio AF. Keep an eye on adenosine: Its role in retinal inflammation. Pharmacol Ther 2020; 210:107513. [PMID: 32109489 DOI: 10.1016/j.pharmthera.2020.107513] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Adenosine is an endogenous purine nucleoside ubiquitously distributed throughout the body that interacts with G protein-coupled receptors, classified in four subtypes: A1R, A2AR, A2BR and A3R. Among the plethora of functions of adenosine, it has been increasingly recognized as a key mediator of the immune response. Neuroinflammation is a feature of chronic neurodegenerative diseases and contributes to the pathophysiology of several retinal degenerative diseases. Animal models of retinal diseases are helping to elucidate the regulatory roles of adenosine receptors in the development and progression of those diseases. Mounting evidence demonstrates that the adenosinergic system is altered in the retina during pathological conditions, compromising retinal physiology. This review focuses on the roles played by adenosine and the elements of the adenosinergic system (receptors, enzymes, transporters) in the neuroinflammatory processes occurring in the retina. An improved understanding of the molecular and cellular mechanisms of the signalling pathways mediated by adenosine underlying the onset and progression of retinal diseases will pave the way towards the identification of new therapeutic approaches.
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Affiliation(s)
- Ana Raquel Santiago
- Faculty of Medicine, Coimbra Institute for Clinical and Biomedical Research (iCBR), University of Coimbra, 3000-548 Coimbra, Portugal; Center for Innovative Biomedicine and Biotechnology (CIBB), University of Coimbra, 3000-548 Coimbra, Portugal; Association for Innovation and Biomedical Research on Light and Image (AIBILI), Coimbra, 3000-548 Coimbra, Portugal.
| | - Maria H Madeira
- Faculty of Medicine, Coimbra Institute for Clinical and Biomedical Research (iCBR), University of Coimbra, 3000-548 Coimbra, Portugal; Center for Innovative Biomedicine and Biotechnology (CIBB), University of Coimbra, 3000-548 Coimbra, Portugal; Association for Innovation and Biomedical Research on Light and Image (AIBILI), Coimbra, 3000-548 Coimbra, Portugal
| | - Raquel Boia
- Faculty of Medicine, Coimbra Institute for Clinical and Biomedical Research (iCBR), University of Coimbra, 3000-548 Coimbra, Portugal; Center for Innovative Biomedicine and Biotechnology (CIBB), University of Coimbra, 3000-548 Coimbra, Portugal
| | - Inês Dinis Aires
- Faculty of Medicine, Coimbra Institute for Clinical and Biomedical Research (iCBR), University of Coimbra, 3000-548 Coimbra, Portugal; Center for Innovative Biomedicine and Biotechnology (CIBB), University of Coimbra, 3000-548 Coimbra, Portugal
| | - Ana Catarina Rodrigues-Neves
- Faculty of Medicine, Coimbra Institute for Clinical and Biomedical Research (iCBR), University of Coimbra, 3000-548 Coimbra, Portugal; Center for Innovative Biomedicine and Biotechnology (CIBB), University of Coimbra, 3000-548 Coimbra, Portugal
| | - Paulo Fernando Santos
- Faculty of Medicine, Coimbra Institute for Clinical and Biomedical Research (iCBR), University of Coimbra, 3000-548 Coimbra, Portugal; Center for Innovative Biomedicine and Biotechnology (CIBB), University of Coimbra, 3000-548 Coimbra, Portugal; Department of Life Sciences, University of Coimbra, 3000-456 Coimbra, Portugal
| | - António Francisco Ambrósio
- Faculty of Medicine, Coimbra Institute for Clinical and Biomedical Research (iCBR), University of Coimbra, 3000-548 Coimbra, Portugal; Center for Innovative Biomedicine and Biotechnology (CIBB), University of Coimbra, 3000-548 Coimbra, Portugal; Association for Innovation and Biomedical Research on Light and Image (AIBILI), Coimbra, 3000-548 Coimbra, Portugal.
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5
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Xu Y, Wang Y, Yan S, Zhou Y, Yang Q, Pan Y, Zeng X, An X, Liu Z, Wang L, Xu J, Cao Y, Fulton DJ, Weintraub NL, Bagi Z, Hoda MN, Wang X, Li Q, Hong M, Jiang X, Boison D, Weber C, Wu C, Huo Y. Intracellular adenosine regulates epigenetic programming in endothelial cells to promote angiogenesis. EMBO Mol Med 2018; 9:1263-1278. [PMID: 28751580 PMCID: PMC5582416 DOI: 10.15252/emmm.201607066] [Citation(s) in RCA: 61] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
The nucleoside adenosine is a potent regulator of vascular homeostasis, but it remains unclear how expression or function of the adenosine‐metabolizing enzyme adenosine kinase (ADK) and the intracellular adenosine levels influence angiogenesis. We show here that hypoxia lowered the expression of ADK and increased the levels of intracellular adenosine in human endothelial cells. Knockdown (KD) of ADK elevated intracellular adenosine, promoted proliferation, migration, and angiogenic sprouting in human endothelial cells. Additionally, mice deficient in endothelial ADK displayed increased angiogenesis as evidenced by the rapid development of the retinal and hindbrain vasculature, increased healing of skin wounds, and prompt recovery of arterial blood flow in the ischemic hindlimb. Mechanistically, hypomethylation of the promoters of a series of pro‐angiogenic genes, especially for VEGFR2 in ADK KD cells, was demonstrated by the Infinium methylation assay. Methylation‐specific PCR, bisulfite sequencing, and methylated DNA immunoprecipitation further confirmed hypomethylation in the promoter region of VEGFR2 in ADK‐deficient endothelial cells. Accordingly, loss or inactivation of ADK increased VEGFR2 expression and signaling in endothelial cells. Based on these findings, we propose that ADK downregulation‐induced elevation of intracellular adenosine levels in endothelial cells in the setting of hypoxia is one of the crucial intrinsic mechanisms that promote angiogenesis.
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Affiliation(s)
- Yiming Xu
- Vascular Biology Center, Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, GA, USA .,School of Basic Medical Sciences, Guangzhou Medical University, Guangzhou, China
| | - Yong Wang
- Vascular Biology Center, Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, GA, USA.,College of Basic Medicine, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Siyuan Yan
- Vascular Biology Center, Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, GA, USA.,State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Science, Beijing, China
| | - Yaqi Zhou
- Vascular Biology Center, Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, GA, USA.,Drug Discovery Center, Key Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School, Shenzhen, China
| | - Qiuhua Yang
- Vascular Biology Center, Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, GA, USA.,Drug Discovery Center, Key Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School, Shenzhen, China
| | - Yue Pan
- Georgia Prevention Institute, Augusta University, Augusta, GA, USA
| | - Xianqiu Zeng
- Vascular Biology Center, Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, GA, USA.,Drug Discovery Center, Key Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School, Shenzhen, China
| | - Xiaofei An
- Vascular Biology Center, Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, GA, USA
| | - Zhiping Liu
- Vascular Biology Center, Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, GA, USA
| | - Lina Wang
- Vascular Biology Center, Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, GA, USA.,Drug Discovery Center, Key Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School, Shenzhen, China
| | - Jiean Xu
- Vascular Biology Center, Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, GA, USA.,Drug Discovery Center, Key Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School, Shenzhen, China
| | - Yapeng Cao
- Vascular Biology Center, Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, GA, USA.,Drug Discovery Center, Key Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School, Shenzhen, China
| | - David J Fulton
- Vascular Biology Center, Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, GA, USA
| | - Neal L Weintraub
- Vascular Biology Center, Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, GA, USA
| | - Zsolt Bagi
- Vascular Biology Center, Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, GA, USA
| | - Md Nasrul Hoda
- Departments of Medical Laboratory, Imaging & Radiologic Sciences, and Neurology, Augusta University, Augusta, GA, USA
| | - Xiaoling Wang
- Georgia Prevention Institute, Augusta University, Augusta, GA, USA
| | - Qinkai Li
- Drug Discovery Center, Key Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School, Shenzhen, China
| | - Mei Hong
- Drug Discovery Center, Key Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School, Shenzhen, China
| | - Xuejun Jiang
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Science, Beijing, China
| | - Detlev Boison
- Robert S. Dow Neurobiology Laboratories, Legacy Research Institute, Portland, OR, USA
| | - Christian Weber
- Institute for Cardiovascular Prevention, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Chaodong Wu
- Department of Nutrition and Food Science, Texas A&M University, College Station, TX, USA
| | - Yuqing Huo
- Vascular Biology Center, Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, GA, USA
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6
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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: 31] [Impact Index Per Article: 4.4] [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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7
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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: 25] [Impact Index Per Article: 3.6] [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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8
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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: 16] [Impact Index Per Article: 2.0] [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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Escudero C, Roberts JM, Myatt L, Feoktistov I. Impaired adenosine-mediated angiogenesis in preeclampsia: potential implications for fetal programming. Front Pharmacol 2014; 5:134. [PMID: 24926270 PMCID: PMC4046493 DOI: 10.3389/fphar.2014.00134] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Accepted: 05/16/2014] [Indexed: 01/24/2023] Open
Abstract
Preeclampsia is a pregnancy-specific syndrome, defined by such clinical hallmarks as the onset of maternal hypertension and proteinuria after 20 weeks of gestation. The syndrome is also characterized by impaired blood flow through the utero-placental circulation and relative placental ischemia, which in turn, may generate feto-placental endothelial dysfunction. Endothelial dysfunction in offspring born from preeclamptic pregnancies has been associated with an increased risk of cardiovascular disease, including hypertension, later in life. Interestingly, diminished endothelial function, manifested by low angiogenic capacity, leads to hypertension in animal studies. Recently, we have shown that the adenosine receptor A2A/nitric oxide/vascular endothelial growth factor axis is reduced in human umbilical vein endothelial cells derived from preeclamptic pregnancies, an effect correlated with gestational age at onset of preeclampsia. We and others suggested that impaired vascular function might be associated with high cardiovascular risk in offspring exposed to pregnancy diseases. However, we are not aware of any studies that examine impaired adenosine-mediated angiogenesis as a possible link to hypertension in offspring born from preeclamptic pregnancies. In this review, we present evidence supporting the hypothesis that reduced adenosine-mediated angiogenesis during preeclamptic pregnancies might be associated with development of hypertension in the offspring.
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Affiliation(s)
- Carlos Escudero
- Vascular Physiology Laboratory, Group of Investigation in Tumor Angiogenesis, Group of Research and Innovation in Vascular Health, Department of Basic Sciences, Faculty of Sciences, Universidad del Bío-Bío Chillán, Chile
| | - James M Roberts
- Magee-Womens Research Institute, Department of Obstetrics, Gynecology, and Reproductive Sciences, Department of Epidemiology and Clinical and Translational Science Institute, University of Pittsburgh Pittsburgh, PA, USA
| | - Leslie Myatt
- Center for Pregnancy and Newborn Research, University of Texas Health Science Center San Antonio, TX, USA
| | - Igor Feoktistov
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University Nashville, TN, USA ; Department of Pharmacology, School of Medicine, Vanderbilt University Nashville, TN, USA
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10
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Li H, Jin SY, Son HJ, Seo JH, Jeong GB. Caffeine-induced endothelial cell death and the inhibition of angiogenesis. Anat Cell Biol 2013; 46:57-67. [PMID: 23560237 PMCID: PMC3615613 DOI: 10.5115/acb.2013.46.1.57] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2013] [Revised: 03/12/2013] [Accepted: 03/12/2013] [Indexed: 12/19/2022] Open
Abstract
Numerous studies have shown that adenosine or adenosine agonists can stimulate angiogenesis. However, the effect of caffeine (a known adenosine receptor antagonist) on angiogenesis has not been previously studied. Accordingly, this study was undertaken to examine the effect of caffeine on angiogenesis and to clarify the mechanism involved. Chick chorioallantoic membrane assays were used to investigate the effect of caffeine on angiogenesis and proliferation assays using human umbilical vein endothelial cells (HUVECs), were used to study its effects on specific aspects of angiogenesis. The expressions of caspase-3 and Bcl-2 were examined by western blotting, immunofluorescence staining was used to identify HUVEC morphological changes, and fluorescence activated cell sorting (FACS) and DAPI staining were used to detect HUVEC apoptosis. Caffeine was found to inhibit blood vessel formation dose-dependently and to inhibit the proliferation of HUVECs time- and dose-dependently. FACS analysis and DAPI staining showed that inhibitory effect of caffeine on HUVEC proliferation was the result of apoptosis and the up-regulation of thrombospondin-1 (TSP-1). Furthermore, TSP-1 levels were down-regulated by NECA but were unaffected by CGS21680, indicating that caffeine regulated TSP-1 expression via adenosine A2B receptor. In addition, caffeine up-regulated caspase-3 and down-regulated Bcl-2 at the protein level. These results suggest that the inhibitory effect of caffeine on angiogenesis is associated, at least in part, with its induction of endothelial cell apoptosis, probably mediated by a caspase-3 dependent mechanism.
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Affiliation(s)
- Hua Li
- Department of Anatomy, Chungbuk National University Medical School, Cheongju, Korea
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11
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Feoktistov I, Biaggioni I. Role of adenosine A(2B) receptors in inflammation. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2011; 61:115-44. [PMID: 21586358 PMCID: PMC3748596 DOI: 10.1016/b978-0-12-385526-8.00005-9] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Recent progress in our understanding of the unique role of A(2B) receptors in the regulation of inflammation, immunity, and tissue repair was considerably facilitated with the introduction of new pharmacological and genetic tools. However, it also led to seemingly conflicting conclusions on the role of A(2B) adenosine receptors in inflammation with some publications indicating proinflammatory effects and others suggesting the opposite. This chapter reviews the functions of A(2B) receptors in various cell types related to inflammation and integrated effects of A(2B) receptor modulation in several animal models of inflammation. It is argued that translation of current findings into novel therapies would require a better understanding of A(2B) receptor functions in diverse types of inflammatory responses in various tissues and at different points of their progression.
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Affiliation(s)
- Igor Feoktistov
- Department of Medicine, Vanderbilt University, Division of Cardiovascular Medicine, Nashville, Tennessee, USA
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12
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Feoktistov I, Biaggioni I, Cronstein BN. Adenosine receptors in wound healing, fibrosis and angiogenesis. Handb Exp Pharmacol 2009:383-97. [PMID: 19639289 DOI: 10.1007/978-3-540-89615-9_13] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Wound healing and tissue repair are critical processes, and adenosine, released from injured or ischemic tissues, plays an important role in promoting wound healing and tissue repair. Recent studies in genetically manipulated mice demonstrate that adenosine receptors are required for appropriate granulation tissue formation and in adequate wound healing. A(2A) and A(2B) adenosine receptors stimulate both of the critical functions in granulation tissue formation (i.e., new matrix production and angiogenesis), and the A(1) adenosine receptor (AR) may also contribute to new vessel formation. The effects of adenosine acting on these receptors is both direct and indirect, as AR activation suppresses antiangiogenic factor production by endothelial cells, promotes endothelial cell proliferation, and stimulates angiogenic factor production by endothelial cells and other cells present in the wound. Similarly, adenosine, acting at its receptors, stimulates collagen matrix formation directly. Like many other biological processes, AR-mediated promotion of tissue repair is critical for appropriate wound healing but may also contribute to pathogenic processes. Excessive tissue repair can lead to problems such as scarring and organ fibrosis and adenosine, and its receptors play a role in pathologic fibrosis as well. Here we review the evidence for the involvement of adenosine and its receptors in wound healing, tissue repair and fibrosis.
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Affiliation(s)
- Igor Feoktistov
- Division of Cardiovascular Medicine, Vanderbilt University, Nashville, TN 37232-6300, USA.
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13
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El-Dairi MA, Wallace DK. Advances in the management of retinopathy of prematurity. EXPERT REVIEW OF OPHTHALMOLOGY 2007. [DOI: 10.1586/17469899.2.3.429] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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15
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Peart JN, Headrick JP. Adenosinergic cardioprotection: Multiple receptors, multiple pathways. Pharmacol Ther 2007; 114:208-21. [PMID: 17408751 DOI: 10.1016/j.pharmthera.2007.02.004] [Citation(s) in RCA: 130] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2007] [Accepted: 02/08/2007] [Indexed: 11/18/2022]
Abstract
Adenosine, formed primarily via hydrolysis of 5'-AMP, has been historically dubbed a "retaliatory" metabolite due to enhanced local release and beneficial actions during cellular/metabolic stress. From a cardiovascular perspective, evidence indicates the adenosinergic system is essential in mediation of intrinsic protection (e.g., pre- and postconditioning) and determining myocardial resistance to insult. Modulation of adenosine and its receptors thus remains a promising, though as yet not well-realized, approach to amelioration of injury in ischemic-reperfused myocardium. Adenosine exerts effects through A(1), A(2A), A(2B), and A(3) adenosine receptor subtypes (A(1)AR, A(2A)AR, A(2B)AR, and A(3)AR), which are all expressed in myocardial and vascular cells, and couple to G proteins to trigger a range of responses (generally, but not always, beneficial). Adenosine can also enhance tolerance to injurious stimuli via receptor-independent metabolic effects. Given adenosines contribution to preconditioning, it is no surprise that postreceptor signaling typically mimics that associated with preconditioning. This involves activation/translocation of PKC, PI3 kinase, and MAPKs, with ultimate effects at the level of mitochondrial targets-the mitochondrial K(ATP) channel and/or the mitochondrial permeability transition pore (mPTP). Nonetheless, differences in cytoprotective signaling and actions of the different adenosine receptor subtypes have been recently revealed. Our understanding of adenosinergic cytoprotection continues to evolve, with roles for the A(2) subtypes emerging, together with evidence of essential receptor "cross-talk" in mediation of protection. This review focuses on current research into adenosine-mediated cardioprotection, highlighting recent findings which, together with a wealth of prior knowledge, may ultimately facilitate adenosinergic approaches to clinical cardiac protection.
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Affiliation(s)
- Jason N Peart
- Heart Foundation Research Center, Griffith University, PMB 50 Gold Coast Mail Center, QLD, 4217, Australia.
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Chan ESL, Fernandez P, Cronstein BN. Adenosine in inflammatory joint diseases. Purinergic Signal 2007; 3:145-52. [PMID: 18404428 PMCID: PMC2096754 DOI: 10.1007/s11302-006-9046-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2006] [Accepted: 02/20/2006] [Indexed: 11/29/2022] Open
Abstract
Inflammatory joint diseases are a group of heterogeneous disorders with a variety of different etiologies and disease manifestations. However, there are features that are common to all of them: first, the recruitment of various inflammatory cell types that are attracted to involved tissues over the course of the disease process. Second, the treatments used in many of these diseases are commonly medications that suppress or alter immune function. The demonstration that adenosine has endogenous anti-inflammatory functions and that some of the most commonly used anti-rheumatic medications exert their therapeutic effects through stimulation of adenosine release suggest an important role for purinergic signaling in inflammatory rheumatic disorders.
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Affiliation(s)
- E S L Chan
- Department of Medicine, Divisions of Clinical Pharmacology and Rheumatology, New York University School of Medicine, New York, NY, USA
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Ashton KJ, Peart JN, Morrison RR, Matherne GP, Blackburn MR, Headrick JP. Genetic modulation of adenosine receptor function and adenosine handling in murine hearts: insights and issues. J Mol Cell Cardiol 2006; 42:693-705. [PMID: 17258765 DOI: 10.1016/j.yjmcc.2006.12.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2006] [Revised: 12/20/2006] [Accepted: 12/21/2006] [Indexed: 11/28/2022]
Abstract
The adenosine receptor system has been attributed with a broad range of both physiological and so-called 'retaliatory' functions in the heart and vessels. Despite many years of research, the precise roles of adenosine within the cardiovascular system continue to be debated, and new functions are continually emerging. Adenosine acts via 4 known G-protein-coupled receptor (GPCR) sub-types: A(1), A(2A), A(2B), and A(3) adenosine receptors (ARs). In addition to roles in cardiovascular control, these receptors may represent therapeutic targets, having been attributed with roles in modifying cell death and injury, inflammatory processes, and cardiac and vascular remodeling during/after ischemic or hypoxic insult. A number of models have been developed in which AR sub-types and adenosine handling enzymes have been genetically deleted or transgenically overexpressed in an attempt to more equivocally identify the regulatory functions of these proteins, to identify their potential value as therapeutic targets, and to uncover new regulatory functions of this receptor family. Findings generally support current dogma regarding cardioprotection via A(1) and A(3)ARs, and coronary vasoregulation via A(2)AR sub-types. However, some outcomes are both novel and controversial. This review outlines AR-modified murine models currently under study from the perspective of cardiovascular phenotype.
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Affiliation(s)
- Kevin J Ashton
- Heart Foundation Research Centre, Griffith University Southport, QLD 4217, Australia
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18
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Gessi S, Varani K, Merighi S, Leung E, Mac Lennan S, Baraldi PG, Borea PA. Novel selective antagonist radioligands for the pharmacological study of A(2B) adenosine receptors. Purinergic Signal 2006; 2:583-8. [PMID: 18404460 PMCID: PMC2096665 DOI: 10.1007/s11302-006-9019-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2005] [Revised: 05/09/2006] [Accepted: 05/29/2006] [Indexed: 11/28/2022] Open
Abstract
The adenosine A2B receptor is the least well characterized of the four adenosine subtypes due to the lack of potent and selective agonists and antagonists. Despite the widespread distribution of A2B receptor mRNA, little information is available with regard to their function. The characterization of A2B receptors, through radioligand binding studies, has been performed, until now, by using low-affinity and non-selective antagonists like 1,3-dipropyl-8-cyclopentylxanthine ([3H]DPCPX),(4-(2-[7-amino-2-(2-furyl)-[1,2,4]triazolo-[2,3-a][1,3,5]triazin-5-ylamino]ethyl)-phenol ([3H]ZM 241385) and 3-(3,4-aminobenzyl)-8-(4-oxyacetate)phenyl-1-propyl-xanthine ([125I]ABOPX). Recently, high-affinity radioligands for A2B receptors, [N-(4-cyanophenyl)-2-[4-(2,3,6,7-tetrahydro-2,6-dioxo-1,3-dipropyl-1H-purin-8-yl)-phenoxy]acetamide ([3H]MRS 1754), N-(2-(2-Phenyl-6-[4-(2,2,3,3-tetratritrio-3-phenylpropyl)-piperazine-1-carbonyl]-7H-pyrrolo[2,3-d]pyrimidin-4-ylamino)-ethyl)-acetamide ([3H]OSIP339391) and N-benzo[1,3]dioxol-5-yl-2-[5-(1,3-dipropyl-2,6-dioxo-2,3,6,7-tetrahydro-1H-purin-8-yl)-1-methyl-1H-pyrazol-3-yloxy]-acetamide] ([3H]MRE 2029F20), have been introduced. This minireview offers an overview of these recently developed radioligands and the most important applications of drugs towards A2B receptors.
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Affiliation(s)
- Stefania Gessi
- Department of Clinical and Experimental Medicine, Pharmacology Unit and ‘Interdisciplinary Center for the Study of Inflammation (ICSI),′, Ferrara, Italy
| | - Katia Varani
- Department of Clinical and Experimental Medicine, Pharmacology Unit and ‘Interdisciplinary Center for the Study of Inflammation (ICSI),′, Ferrara, Italy
| | - Stefania Merighi
- Department of Clinical and Experimental Medicine, Pharmacology Unit and ‘Interdisciplinary Center for the Study of Inflammation (ICSI),′, Ferrara, Italy
| | - Edward Leung
- King Pharmaceuticals Research & Development, Cary, NC USA
| | | | | | - Pier Andrea Borea
- Department of Clinical and Experimental Medicine, Pharmacology Unit and ‘Interdisciplinary Center for the Study of Inflammation (ICSI),′, Ferrara, Italy
- Faculty of Medicine, Department of Clinical and Experimental Medicine, Pharmacology Unit, University of Ferrara,, Via Fossato di Mortara 17-19, 44100 Ferrara, Italy
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San Martín R, Sobrevia L. Gestational diabetes and the adenosine/L-arginine/nitric oxide (ALANO) pathway in human umbilical vein endothelium. Placenta 2006; 27:1-10. [PMID: 16310032 DOI: 10.1016/j.placenta.2005.01.011] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/10/2004] [Revised: 01/18/2005] [Accepted: 01/20/2005] [Indexed: 01/22/2023]
Abstract
Altered endothelial cell function is a key factor associated with vascular disorders and is critical in the fetal growth and development. Pregnancies affected by diseases such as gestational diabetes are associated with human umbilical vein endothelial dysfunction, a finding that has been associated with a high incidence of vascular complications during the adult life. Limited information is available addressing cellular mechanisms associated with altered human umbilical vein endothelial function in gestational diabetes. One of the key signalling pathways associated with altered vascular physiology is the synthesis of the vasodilator nitric oxide (NO) from the cationic amino acid L-arginine by the endothelium (i.e. the endothelial L-arginine/NO pathway). The activity of this signalling pathway is modulated by D-glucose, adenosine, insulin, and ATP, among other molecules, and is upregulated (transcriptional, post-transcriptional and post-translational levels) in gestational diabetes. This review focuses on the cellular and molecular mechanisms involved with elevated adenosine levels in fetal umbilical vein blood and the endothelial L-arginine/NO pathway activity in gestational diabetes. We suggest that a lower capacity of adenosine transport by the fetal endothelium in gestational diabetes leads to extracellular accumulation of this nucleoside and its higher bio-availability activates endothelial P1 type purinoceptors. A functional association between A2a purinoceptor subtype signalling and the activity of the l-arginine transport mediated by human cationic amino acid transporters and endothelial NO synthase activity (i.e. 'ALANO pathway') is proposed, revealing in part the mechanisms that account for human umbilical vein endothelial cell dysfunction programmed through the development of the fetus in gestational diabetes.
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Affiliation(s)
- R San Martín
- Cellular and Molecular Physiology Laboratory (CMPL), Department of Obstetrics and Gynaecology, Medical Research Centre (CIM), School of Medicine, Faculty of Medicine, Pontificia Universidad Católica de Chile, P.O. Box 114-D, Santiago, Chile
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Adair TH. Growth regulation of the vascular system: an emerging role for adenosine. Am J Physiol Regul Integr Comp Physiol 2005; 289:R283-R296. [PMID: 16014444 DOI: 10.1152/ajpregu.00840.2004] [Citation(s) in RCA: 141] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The importance of metabolic factors in the regulation of angiogenesis is well understood. An increase in metabolic activity leads to a decrease in tissue oxygenation causing tissues to become hypoxic. The hypoxia initiates a variety of signals that stimulate angiogenesis, and the increase in vascularity that follows promotes oxygen delivery to the tissues. When the tissues receive adequate amounts of oxygen, the intermediate effectors return to normal levels, and angiogenesis ceases. An emerging concept is that adenosine released from hypoxic tissues has an important role in driving the angiogenesis. The following feedback control hypothesis is proposed: AMP is dephosphorylated by ecto-5′-nucleotidase, producing adenosine under hypoxic conditions in the extracellular space adjacent to a parenchymal cell (e.g., cardiomyocyte, skeletal muscle fiber, hepatocyte, etc.). Extracellular adenosine activates A2receptors, which stimulates the release of vascular endothelial growth factor (VEGF) from the parenchymal cell. VEGF binds to its receptor (VEGF receptor 2) on endothelial cells, stimulating their proliferation and migration. Adenosine can also stimulate endothelial cell proliferation independently of VEGF, which probably involves modulation of other proangiogenic and antiangiogenic growth factors and perhaps an intracellular mechanism. In addition, hemodynamic factors associated with adenosine-induced vasodilation may have a role in the development and remodeling of the vasculature. Once a new capillary network has been established, and the diffusion/perfusion capabilities of the vasculature are sufficient to supply the parenchymal cells with adequate amounts of oxygen, adenosine and VEGF as well as other proangiogenic and antiangiogenic growth factors return to near-normal levels, thus closing the negative feedback loop. The available data indicate that adenosine might be an essential mediator for up to 50–70% of the hypoxia-induced angiogenesis in some situations; however, additional studies in intact animals will be required to fully understand the quantitative importance of adenosine.
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Affiliation(s)
- Thomas H Adair
- Dept. of Physiology and Biophysics, University of Mississippi Medical Center, 2500 N. State Street, Jackson, MS 39216-4505, USA.
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Sands WA, Palmer TM. Adenosine receptors and the control of endothelial cell function in inflammatory disease. Immunol Lett 2005; 101:1-11. [PMID: 15878624 DOI: 10.1016/j.imlet.2005.04.005] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2005] [Indexed: 10/25/2022]
Abstract
The nucleoside adenosine accumulates in many tissues following the onset of ischaemia and inflammation. This initiates a series of protective mechanisms in target cells upon binding and activation of a family of four G-protein-coupled cell surface adenosine receptor (AR) proteins. The magnitude and duration of adenosine's effects are dictated by the identity and expression levels of each receptor subtype on individual cell types within the hypoxic microenvironment. Given the key role of endothelial cells (ECs) in the development of inflammatory diseases, such as sepsis, rheumatoid arthritis (RA) and atherosclerosis, ARs represent attractive targets for therapeutic intervention in these conditions. In this review, we examine several critical aspects of endothelial function in vivo, assess the role of individual AR subtypes in these events and, where known, discuss the molecular mechanisms by which specific ARs exert their effects.
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Affiliation(s)
- William A Sands
- Molecular Pharmacology Group, Division of Biochemistry and Molecular Biology, Institute of Biomedical and Life Sciences, University of Glasgow, Glasgow G12 8QQ, Scotland, UK
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Gessi S, Varani K, Merighi S, Cattabriga E, Pancaldi C, Szabadkai Y, Rizzuto R, Klotz KN, Leung E, Mac Lennan S, Baraldi PG, Borea PA. Expression, Pharmacological Profile, and Functional Coupling of A2BReceptors in a Recombinant System and in Peripheral Blood Cells Using a Novel Selective Antagonist Radioligand, [3H]MRE 2029-F20. Mol Pharmacol 2005; 67:2137-47. [PMID: 15788741 DOI: 10.1124/mol.104.009225] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
In this study, we compared the pharmacological and biochemical characteristics of A(2B) adenosine receptors in recombinant (hA(2B)HEK293 cells) and native cells (neutrophils, lymphocytes) by using a new potent 8-pyrazole xanthine derivative, [(3)H]N-benzo[1,3]dioxol-5-yl-2-[5-(1,3-dipropyl-2,6-dioxo-2,3,6,7-tetrahydro-1H-purin-8-yl)-1-methyl-1H-pyrazol-3-yl-oxy]-acetamide] ([(3)H]MRE 2029-F20), that has high affinity and selectivity for hA(2B) versus hA(1),hA(2A), and hA(3) subtypes. [(3)H]MRE 2029-F20 bound specifically to the hA(2B) receptor stably transfected in human embryonic kidney (HEK) 293 cells with K(D) of 2.8 +/- 0.2 nM and B(max) of 450 +/- 42 fmol/mg of protein. Saturation experiments of [(3)H]MRE 2029-F20 binding in human neutrophils and lymphocytes detected a single high-affinity binding site with K(D) values of 2.4 +/- 0.5 and 2.7 +/- 0.7 nM, respectively, and B(max) values of 79 +/- 10 and 54 +/- 8 fmol/mg of protein, respectively, in agreement with real-time reverse transcription polymerase chain reaction studies showing the presence of A(2B) mRNA. The rank order of potency of typical adenosine ligands with recombinant hA(2B) receptors was consistent with that typically found for interactions with the A(2B) subtype and was also similar in peripheral blood cells. 5'-N-Ethyl-carboxamidoadenosine stimulated cAMP accumulation in both hA(2B)HEK293 and native cells, whereas phospholipase C activation was observed in recombinant receptors and endogenous subtypes expressed in neutrophils but not in lymphocytes. MRE 2029-F20 was revealed to be a potent antagonist in counteracting the agonist effect in both signal transduction pathways. In conclusion, [(3)H]MRE 2029-F20 is a selective and high-affinity radioligand for the hA(2B) adenosine subtype and may be used to quantify A(2B) endogenous receptors. In this work, we demonstrated their presence and functional coupling in neutrophils and lymphocytes that play a role in inflammatory processes in which A(2B) receptors may be involved.
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Affiliation(s)
- Stefania Gessi
- Faculty of Medicine, Department of Clinical and Experimental Medicine, Pharmacology Unit, University of Ferrara, Via Fossato di Mortara 17-19, 44100 Ferrara, Italy
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Grant MB, Afzal A, Spoerri P, Pan H, Shaw LC, Mames RN. The role of growth factors in the pathogenesis of diabetic retinopathy. Expert Opin Investig Drugs 2005; 13:1275-93. [PMID: 15461557 DOI: 10.1517/13543784.13.10.1275] [Citation(s) in RCA: 111] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Diabetic retinopathy (DR) is the most severe of several ocular complications of diabetes. The earliest clinical signs of DR are microaneurysms and haemorrhages. Later signs include dilated, tortuous irregular veins and retinal non-profusion, leading to retinal ischaemia that ultimately results in neovascularisation. Diabetic macular oedema, which involves the breakdown of the blood-retinal barrier, also occurs and is responsible for a major part of vision loss, particularly in Type 2 diabetes. The pathogenesis of DR is very complex. Many biochemical mechanisms have been proposed as explanations for the development and progression of DR. Chronic hyperglycaemia leads to oxidative injury, microthrombi formation, cell adhesion molecule activation, leukostasis and cytokine activation. Next, ischaemia-mediated overexpression of growth factors and cytokines occurs. These factors include vascular endothelial growth factor, insulin-like growth factor-1, angiopoetin-1 and -2, stromal-derived factor-1, fibroblast growth factor-2 and tumour necrosis factor. Because of the complex interplay between these factors, targeting a single growth factor will be unlikely to result in therapeutic inhibition of angiogenesis. These growth factors no doubt act in synergy to mediate the steps of angiogenesis, including protease production, endothelial cell proliferation, migration and tube formation. This review attempts to provide an overview of perspectives regarding the pathogenesis of this disease. The focus, however, is on describing the unique features of selected relevant factors and how each growth factor may act in a synergistic manner with other factors.
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Affiliation(s)
- Maria B Grant
- University of Florida, Department of Pharmacology and Therapeutics, 1600 SW Archer Road, PO Box 100267, Gainesville, FL 32610, USA.
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McFarland TJ, Zhang Y, Appukuttan B, Stout JT. Gene therapy for proliferative ocular diseases. Expert Opin Biol Ther 2005; 4:1053-8. [PMID: 15268673 DOI: 10.1517/14712598.4.7.1053] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Proliferative ocular diseases encompass a wide variety of pathological processes with adverse cellular differentiation, proliferation and migration as common features. Pathologies may involve neovascular responses associated with diabetic retinopathy, retinopathy of prematurity or age-related macular degeneration. These diseases are quite prevalent and account for substantial visual impairment and blindness worldwide. Although treatment strategies are largely surgical, advances in our understanding of the proteins crucial to cell transdifferentiation, proliferation and migration, along with better gene transfer techniques, have greatly increased the potential for biological treatment options. In this report, the most common proliferative ocular vascular diseases and existing therapeutic modalities will be reviewed and an overview of possible gene therapy options will be discussed, along with potential candidate genes.
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Affiliation(s)
- Trevor J McFarland
- Casey Eye Institute, OHSU, 3375 SW Terwilliger BLVD, Portland, OR 97239, USA
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Desai A, Victor-Vega C, Gadangi S, Montesinos MC, Chu CC, Cronstein BN. Adenosine A2A receptor stimulation increases angiogenesis by down-regulating production of the antiangiogenic matrix protein thrombospondin 1. Mol Pharmacol 2005; 67:1406-13. [PMID: 15673602 DOI: 10.1124/mol.104.007807] [Citation(s) in RCA: 92] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Topical adenosine A2A receptor agonists promote wound healing by, among other effects, increasing microvessel formation. Results of representational display analysis of human umbilical vein endothelial cells suggested that A2A receptor occupancy modulates expression of the antiangiogenic matrix protein thrombospondin 1 (TSP1). We therefore determined whether A2A receptor occupation stimulates angiogenesis by modulating TSP1 secretion. Human microvascular endothelial cells (HMVEC) were treated with medium alone, 2-p-[2-carboxyethyl] phenethyl-amino-5'-N-ethylcarboxamido-adenosine (CGS-21680), or 2-[2-(4-chlorophenyl)ethoxy]adenosine (MRE0094), selective A2A receptor agonists. TSP1 protein secretion was down-regulated after treatment with the A2A agonists CGS-21680 or MRE0094 in a dose-dependent manner (EC50 = 6.65 nM and 0.23 microM respectively). The selective A2A receptor antagonist 4-[2-[7-amino-2-(2-furyl)[1,2,4]triazolo-[2,3-a][1,3,5]triazin-5-ylamino]ethyl]phenol (ZM241385) but not the A1 and A2B receptor antagonists diphenylcyclopentylxanthine, enprofylline, and N-(4-acetylphenyl)-2-[4-(2,3,6,7-tetrahydro-2,6-dioxo-1,3-dipropyl-1H-purin-8-yl)phenoxy]acetamide (MRS1706) completely abrogated the A2A receptor agonist-mediated effect on TSP1. Vascular tube formation by HMVEC was increased by adenosine A2A receptor agonists in a dose-dependent fashion (EC50 = 0.1 microM for both), and this effect was reversed by the A2A antagonist. Moreover, in the presence of antibodies to TSP1 and CD36, the receptor for TSP1, the adenosine A2A receptor agonists stimulated no increase in vascular tube formation. These results indicate that the angiogenic effects of adenosine A2A receptor activation are, at least in part, caused by the suppression of TSP1 secretion.
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Affiliation(s)
- Avani Desai
- Department of Medicine, New York University School of Medicine, New York, New York 10016, USA
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Wang L, Kolachala V, Walia B, Balasubramanian S, Hall RA, Merlin D, Sitaraman SV. Agonist-induced polarized trafficking and surface expression of the adenosine 2b receptor in intestinal epithelial cells: role of SNARE proteins. Am J Physiol Gastrointest Liver Physiol 2004; 287:G1100-7. [PMID: 15256361 DOI: 10.1152/ajpgi.00164.2004] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Adenosine, acting through the A2b receptor, induces vectorial chloride and IL-6 secretion in intestinal epithelia and may play an important role in intestinal inflammation. We have previously shown that apical or basolateral adenosine receptor stimulation results in the recruitment of the A2b receptor to the plasma membrane. In this study, we examined domain specificity of recruitment and the role of soluble N-ethylmaleimide (NEM) attachment receptor (SNARE) proteins in the agonist-mediated recruitment of the A2b receptor to the membrane. The colonic epithelial cell line T84 was used because it only expresses the A2b-subtype adenosine receptor. Cell fractionation, biotinylation, and electron microscopic studies showed that the A2b receptor is intracellular at rest and that apical or basolateral adenosine stimulation resulted in the recruitment of the receptor to the apical membrane. Upon agonist stimulation, the A2b receptor is enriched in the vesicle fraction containing vesicle-associated membrane protein (VAMP)-2. Furthermore, in cells stimulated with apical or basolateral adenosine, we demonstrate a complex consisting of VAMP-2, soluble NEM-sensitive factor attachment protein (SNAP)-23, and A2b receptor that is coimmunoprecipitated in cells stimulated with adenosine within 5 min and is no longer detected within 15 min. Inhibition of trafficking with NEM or nocodazole inhibits cAMP synthesis induced by apical or basolateral adenosine by 98 and 90%, respectively. cAMP synthesis induced by foskolin was not affected, suggesting that generalized signaling is not affected under these conditions. Collectively, our data suggest that 1) the A2b receptor is intracellular at rest; 2) apical or basolateral agonist stimulation induces recruitment of the A2b receptor to the apical membrane; 3) the SNARE proteins, VAMP-2 and SNAP-23, participate in the recruitment of the A2b receptor; and 4) the SNARE-mediated recruitment of the A2b receptor may be required for its signaling.
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Affiliation(s)
- Lixin Wang
- Division of Digestive Diseases, Department of Medicine, Emory University, Atlanta, GA 30322, USA
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Abstract
PURPOSE OF REVIEW The purpose of this review is not to provide an extensive overview of well-established mechanisms of angiogenesis and lymphangiogenesis but rather to highlight several recent key studies that constituted a significant conceptual or medical advancement to the field during the past year or so. The authors apologize for their inability, because of space restrictions, to reference all other relevant work of the past or previous years. RECENT FINDINGS In 1993, fewer than 400 studies on angiogenesis were published. During the past year alone, more than 4000 angiogenesis studies were reported, making angiogenesis one of the most rapidly growing fields. Moreover, the first studies on lymphangiogenesis were published only a couple of years ago. A milestone in the field in the past year has been the first successful report that the angiogenesis inhibitor bevacizumab (Avastin), an antibody against vascular endothelial growth factor, prolonged the survival of colorectal and renal cancer patients in phase 3 clinical trials. This remarkable achievement provides great promise and hope for the future development of therapeutic strategies to inhibit or stimulate angiogenesis. SUMMARY The intensive search for antiangiogenic and proangiogenic mechanisms during the past decade is starting to translate into clinical promise. Further discovery of novel pathways and concepts in angiogenesis may lead to the optimization and refinement of current strategies to improve the clinical benefit and therapeutic safety for a vast number of patients with angiogenesis-related disease.
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Affiliation(s)
- Aernout Luttun
- Center for Transgene Technology and Gene Therapy, Flanders Interuniversity Institute for Biotechnology, Leuven, Belgium
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