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Muramatsu A, Nakamura S, Hirayama T, Nagasawa H, Ohira A, Kitaoka T, Hara H, Shimazawa M. Both hemoglobin and hemin cause damage to retinal pigment epithelium through the iron ion accumulation. J Pharmacol Sci 2024; 155:44-51. [PMID: 38677785 DOI: 10.1016/j.jphs.2024.04.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2023] [Revised: 03/25/2024] [Accepted: 04/01/2024] [Indexed: 04/29/2024] Open
Abstract
Subretinal hemorrhages result in poor vision and visual field defects. During hemorrhage, several potentially toxic substances are released from iron-based hemoglobin and hemin, inducing cellular damage, the detailed mechanisms of which remain unknown. We examined the effects of excess intracellular iron on retinal pigment epithelial (RPE) cells. A Fe2+ probe, SiRhoNox-1 was used to investigate Fe2+ accumulation after treatment with hemoglobin or hemin in the human RPE cell line ARPE-19. We also evaluated the production of reactive oxygen species (ROS) and lipid peroxidation. Furthermore, the protective effect of-an iron chelator, 2,2'-bipyridyl (BP), and ferrostatin-1 (Fer-1) on the cell damage, was evaluated. Fe2+ accumulation increased in the hemoglobin- or hemin-treated groups, as well as intracellular ROS production and lipid peroxidation. In contrast, BP treatment suppressed RPE cell death, ROS production, and lipid peroxidation. Pretreatment with Fer-1 ameliorated cell death in a concentration-dependent manner and suppressed ROS production and lipid peroxidation. Taken together, these findings indicate that hemoglobin and hemin, as well as subretinal hemorrhage, may induce RPE cell damage and visual dysfunction via intracellular iron accumulation.
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Affiliation(s)
- Aomi Muramatsu
- Molecular Pharmacology, Department of Biofunctional Evaluation, Gifu Pharmaceutical University, Gifu, Japan
| | - Shinsuke Nakamura
- Molecular Pharmacology, Department of Biofunctional Evaluation, Gifu Pharmaceutical University, Gifu, Japan
| | - Tasuku Hirayama
- Laboratory of Pharmaceutical and Medical Chemistry, Gifu Pharmaceutical University, Gifu, Japan
| | - Hideko Nagasawa
- Laboratory of Pharmaceutical and Medical Chemistry, Gifu Pharmaceutical University, Gifu, Japan
| | - Akihiro Ohira
- Department of Ophthalmology and Visual Sciences, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
| | - Takashi Kitaoka
- Department of Ophthalmology and Visual Sciences, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
| | - Hideaki Hara
- Molecular Pharmacology, Department of Biofunctional Evaluation, Gifu Pharmaceutical University, Gifu, Japan
| | - Masamitsu Shimazawa
- Molecular Pharmacology, Department of Biofunctional Evaluation, Gifu Pharmaceutical University, Gifu, Japan.
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2
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Heavener K, Kabra K, Yidenk M, Bradshaw E. IL-1RA Disrupts ATP Activation of P2RX7 in Human Monocyte-Derived Microglia-like Cells. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.08.588607. [PMID: 38645234 PMCID: PMC11030313 DOI: 10.1101/2024.04.08.588607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/23/2024]
Abstract
The immune system has a dynamic role in neurodegenerative diseases, and purinergic receptors allow immune cells to recognize neuronal signaling, cell injury, or stress. Purinergic Receptor 7 (P2RX7) can modulate inflammatory cascades and its expression is upregulated in Alzheimer's disease (AD) brain tissue. P2RX7 expression is enriched in microglia, and elevated levels are found in microglia surrounding amyloid-beta plaques in the brain. While P2RX7 is thought to play a role in neurodegenerative diseases, how it modulates pathology and disease progression is not well understood. Here, we utilize a human monocyte-derived microglia-like cell (MDMi) model to interrogate P2RX7 activation and downstream consequences on microglia function. By using MDMi derived from human donors, we can examine how human donor variation impacts microglia function. We assessed P2RX7-driven IL1β and IL18 production and amyloid-beta peptide 1-42 (Aβ1-42) uptake levels. Our results show that ATP-stimulation of MDMi triggers upregulation of IL1β and IL18 expression. This upregulation of cytokine gene expression is blocked with the A740003 P2RX7 antagonist. We find that high extracellular ATP conditions also reduced MDMi capacity for Aβ1-42 uptake, and this loss of function is prevented through A740003 inhibition of P2RX7. In addition, pretreatment of MDMi with IL-1RA limited ATP-driven IL1β and IL18 gene expression upregulation, indicating that ATP immunomodulation of P2RX7 is IL-1R dependent. Aβ1-42 uptake was higher with IL-1RA pretreatment compared to ATP treatment alone, suggesting P2RX7 regulates phagocytic engulfment through IL-1 signaling. Overall, our results demonstrate that P2RX7 is a key response protein for high extracellular ATP in human microglia-like cells, and its function can be modulated by IL-1 signaling. This work opens the door to future studies examining anti-IL-1 biologics to increase the clearance of amyloid-beta.
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Affiliation(s)
- Kelsey Heavener
- Division of Translational Neurobiology, Departments of Neurology Columbia University Medical Center, 630 West 168th Street, New York, NY 10032, USA
- The Carol and Gene Ludwig Center for Research on Neurodegeneration, Departments of Neurology Columbia University Medical Center, 630 West 168th Street, New York, NY 10032, USA
| | - Khushbu Kabra
- Division of Translational Neurobiology, Departments of Neurology Columbia University Medical Center, 630 West 168th Street, New York, NY 10032, USA
- The Carol and Gene Ludwig Center for Research on Neurodegeneration, Departments of Neurology Columbia University Medical Center, 630 West 168th Street, New York, NY 10032, USA
| | - Maedot Yidenk
- Division of Translational Neurobiology, Departments of Neurology Columbia University Medical Center, 630 West 168th Street, New York, NY 10032, USA
- The Carol and Gene Ludwig Center for Research on Neurodegeneration, Departments of Neurology Columbia University Medical Center, 630 West 168th Street, New York, NY 10032, USA
| | - Elizabeth Bradshaw
- Division of Translational Neurobiology, Departments of Neurology Columbia University Medical Center, 630 West 168th Street, New York, NY 10032, USA
- The Carol and Gene Ludwig Center for Research on Neurodegeneration, Departments of Neurology Columbia University Medical Center, 630 West 168th Street, New York, NY 10032, USA
- Taub Institute for Research on Alzheimer’s Disease and the Aging Brain, Departments of Neurology Columbia University Medical Center, 630 West 168th Street, New York, NY 10032, USA
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3
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Ye SS, Wang JN, Zhao YF, Dai LS, Zhang JZ, Zuo YQ, Song JT. Purinergic P2X7 receptor involves in anti-retinal photodamage effects of berberine. Purinergic Signal 2024:10.1007/s11302-024-09999-6. [PMID: 38489005 DOI: 10.1007/s11302-024-09999-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2023] [Accepted: 02/26/2024] [Indexed: 03/17/2024] Open
Abstract
Berberine (BBR) is a Chinese herb with antioxidant and anti-inflammatory properties. In a previous study, we found that BBR had a protective effect against light-induced retinal degeneration in BALB/c mice. The purinergic P2X7 receptor (P2X7R) plays a key role in retinal degeneration via inducing oxidative stress, inflammatory changes, and cell death. The aim of this study was to investigate whether BBR can induce protective effects in light damage experiments and whether P2X7R can get involved in these effects. C57BL/6 J mice and P2X7 knockout (KO) mice on the C57BL/6 J background were used. We found that BBR preserved the outer nuclear layer (ONL) thickness and retinal ganglion cells following light stimulation. Furthermore, BBR significantly suppressed photoreceptor apoptosis, pro-apoptotic c-fos expression, pro-inflammatory responses of Mϋller cells, and inflammatory factors (TNF-α, IL-1β). In addition, protein levels of P2X7R were downregulated in BBR-treated mice. Double immunofluorescence showed that BBR reduced overexpression of P2X7R in retinal ganglion cells and Mϋller cells. Furthermore, BBR combined with the P2X7R agonist BzATP blocked the effects of BBR on retinal morphology and photoreceptor apoptosis. However, in P2X7 KO mice, BBR had an additive effect resulting in thicker ONL and more photoreceptors. The data suggest that the P2X7 receptor is involved in retinal light damage, and BBR inhibits this process by reducing histological impairment, cell death, and inflammatory responses.
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Affiliation(s)
- Shan-Shan Ye
- Eye Hospital, China Academy of Chinese Medical Sciences, Beijing, 100040, China
| | - Jia-Ning Wang
- Eye Hospital, China Academy of Chinese Medical Sciences, Beijing, 100040, China
| | - Ya-Fei Zhao
- School of Acupuncture and Tuina, Chengdu University of Traditional Chinese Medicine, Chengdu, 610075, China
| | - Le-Shu Dai
- Eye Hospital, China Academy of Chinese Medical Sciences, Beijing, 100040, China
- China Academy of Chinese Medical Sciences, Beijing, 100700, China
| | - Ji-Zhou Zhang
- School of Acupuncture and Tuina, Chengdu University of Traditional Chinese Medicine, Chengdu, 610075, China
| | - Yan-Qin Zuo
- School of Acupuncture and Tuina, Chengdu University of Traditional Chinese Medicine, Chengdu, 610075, China
| | - Jian-Tao Song
- Eye Hospital, China Academy of Chinese Medical Sciences, Beijing, 100040, China.
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Bighinati A, Adani E, Stanzani A, D’Alessandro S, Marigo V. Molecular mechanisms underlying inherited photoreceptor degeneration as targets for therapeutic intervention. Front Cell Neurosci 2024; 18:1343544. [PMID: 38370034 PMCID: PMC10869517 DOI: 10.3389/fncel.2024.1343544] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2023] [Accepted: 01/16/2024] [Indexed: 02/20/2024] Open
Abstract
Retinitis pigmentosa (RP) is a form of retinal degeneration characterized by primary degeneration of rod photoreceptors followed by a secondary cone loss that leads to vision impairment and finally blindness. This is a rare disease with mutations in several genes and high genetic heterogeneity. A challenging effort has been the characterization of the molecular mechanisms underlying photoreceptor cell death during the progression of the disease. Some of the cell death pathways have been identified and comprise stress events found in several neurodegenerative diseases such as oxidative stress, inflammation, calcium imbalance and endoplasmic reticulum stress. Other cell death mechanisms appear more relevant to photoreceptor cells, such as high levels of cGMP and metabolic changes. Here we review some of the cell death pathways characterized in the RP mutant retina and discuss preclinical studies of therapeutic approaches targeting the molecular outcomes that lead to photoreceptor cell demise.
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Affiliation(s)
- Andrea Bighinati
- Department of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy
| | - Elisa Adani
- Department of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy
| | - Agnese Stanzani
- Department of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy
| | - Sara D’Alessandro
- Department of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy
| | - Valeria Marigo
- Department of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy
- Center for Neuroscience and Neurotechnology, Modena, Italy
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Olivier E, Rat P. Role of Oxysterols in Ocular Degeneration Mechanisms and Involvement of P2X7 Receptor. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2024; 1440:277-292. [PMID: 38036885 DOI: 10.1007/978-3-031-43883-7_14] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/02/2023]
Abstract
Ocular degeneration, including cataracts, glaucoma, macular degeneration, and diabetic retinopathy, is a major public health challenge, as it affects the quality of life of millions of people worldwide and, in its advanced stages, leads to blindness. Ocular degeneration, although it can affect different parts of the eye, shares common characteristics such as oxysterols and the P2X7 receptor. Indeed, oxysterols, which are cholesterol derivatives, are associated with ocular degeneration pathogenesis and trigger inflammation and cell death pathways. Activation of the P2X7 receptor is also linked to ocular degeneration and triggers the same pathways. In age-related macular degeneration, these two key players have been associated, but further studies are needed to extrapolate this interrelationship to other ocular degenerations.
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Affiliation(s)
| | - Patrice Rat
- Université Paris Cité, CNRS, CiTCoM, Paris, France
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Chhatwal S, Antony H, Lamei S, Kovács-Öller T, Klettner AK, Zille M. A systematic review of the cell death mechanisms in retinal pigment epithelium cells and photoreceptors after subretinal hemorrhage - Implications for treatment options. Biomed Pharmacother 2023; 167:115572. [PMID: 37742603 DOI: 10.1016/j.biopha.2023.115572] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2023] [Revised: 09/12/2023] [Accepted: 09/21/2023] [Indexed: 09/26/2023] Open
Abstract
Humans rely on vision as their most important sense. This is accomplished by photoreceptors (PRs) in the retina that detect light but cannot function without the support and maintenance of the retinal pigment epithelium (RPE). In subretinal hemorrhage (SRH), blood accumulates between the neurosensory retina and the RPE or between the RPE and the choroid. Blood breakdown products subsequently damage PRs and the RPE and lead to poor vision and blindness. Hence, there is a high need for options to preserve the retina and visual functions. We conducted a systematic review of the literature in accordance with the PRISMA guidelines to identify the cell death mechanisms in RPE and PRs after SRH to deepen our understanding of the pathways involved. After screening 736 publications published until November 8, 2022, we identified 19 records that assessed cell death in PRs and/or RPE in experimental models of SRH. Among the different cell death mechanisms, apoptosis was the most widely investigated mechanism (11 records), followed by ferroptosis (4), whereas necroptosis, pyroptosis, and lysosome-dependent cell death were only assessed in one study each. We discuss different therapeutic options that were assessed in these studies, including the removal of the hematoma/iron chelation, cytoprotection, anti-inflammatory agents, and antioxidants. Further systematic investigations will be necessary to determine the exact cell death mechanisms after SRH with respect to different blood breakdown components, cell types, and time courses. This will form the basis for the development of novel treatment options for SRH.
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Affiliation(s)
- Sirjan Chhatwal
- Department of Pharmaceutical Sciences, Division of Pharmacology and Toxicology, University of Vienna, Austria
| | - Henrike Antony
- Department of Pharmaceutical Sciences, Division of Pharmacology and Toxicology, University of Vienna, Austria
| | - Saman Lamei
- Department of Pharmaceutical Sciences, Division of Pharmacology and Toxicology, University of Vienna, Austria
| | - Tamás Kovács-Öller
- János Szentágothai Research Centre, University of Pécs, Pécs, Hungary; Institute of Biology, Faculty of Sciences, University of Pécs, Pécs, Hungary
| | - Alexa Karina Klettner
- Department of Ophthalmology, University Medical Center, University of Kiel, Quincke Research Center, Kiel, Germany
| | - Marietta Zille
- Department of Pharmaceutical Sciences, Division of Pharmacology and Toxicology, University of Vienna, Austria.
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7
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Garg M, Johri S, Chakraborty K. Immunomodulatory role of mitochondrial DAMPs: a missing link in pathology? FEBS J 2023; 290:4395-4418. [PMID: 35731715 DOI: 10.1111/febs.16563] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 05/18/2022] [Accepted: 06/21/2022] [Indexed: 12/01/2022]
Abstract
In accordance with the endosymbiotic theory, mitochondrial components bear characteristic prokaryotic signatures, which act as immunomodulatory molecules when released into the extramitochondrial compartment. These endogenous immune triggers, called mitochondrial damage-associated molecular patterns (mtDAMPs), have been implicated in the pathogenesis of various diseases, yet their role remains largely unexplored. In this review, we summarise the available literature on mtDAMPs in diseases, with a special focus on respiratory diseases. We highlight the need to bolster mtDAMP research using a multipronged approach, to study their effect on specific cell types, receptors and machinery in pathologies. We emphasise the lacunae in the current understanding of mtDAMPs, particularly in their cellular release and the chemical modifications they undergo. Finally, we conclude by proposing additional effects of mtDAMPs in diseases, specifically their role in modulating the immune system.
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Affiliation(s)
- Mayank Garg
- Cardio-Respiratory Disease Biology, CSIR-Institute of Genomics and Integrative Biology, New Delhi, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
| | - Saumya Johri
- Cardio-Respiratory Disease Biology, CSIR-Institute of Genomics and Integrative Biology, New Delhi, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
| | - Krishnendu Chakraborty
- Cardio-Respiratory Disease Biology, CSIR-Institute of Genomics and Integrative Biology, New Delhi, India
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8
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Molcak H, Jiang K, Campbell CJ, Matsubara JA. Purinergic signaling via P2X receptors and mechanisms of unregulated ATP release in the outer retina and age-related macular degeneration. Front Neurosci 2023; 17:1216489. [PMID: 37496736 PMCID: PMC10366617 DOI: 10.3389/fnins.2023.1216489] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Accepted: 06/26/2023] [Indexed: 07/28/2023] Open
Abstract
Age-related macular degeneration (AMD) is a chronic and progressive inflammatory disease of the retina characterized by photoceptor loss and significant central visual impairment due to either choroidal neovascularization or geographic atrophy. The pathophysiology of AMD is complex and multifactorial, driven by a combination of modifiable and non-modifiable risk factors, molecular mechanisms, and cellular processes that contribute to overall disease onset, severity, and progression. Unfortunately, due to the structural, cellular, and pathophysiologic complexity, therapeutic discovery is challenging. While purinergic signaling has been investigated for its role in the development and treatment of ocular pathologies including AMD, the potential crosstalk between known contributors to AMD, such as the complement cascade and inflammasome activation, and other biological systems, such as purinergic signaling, have not been fully characterized. In this review, we explore the interactions between purinergic signaling, ATP release, and known contributors to AMD pathogenesis including complement dysregulation and inflammasome activation. We begin by identifying what is known about purinergic receptors in cell populations of the outer retina and potential sources of extracellular ATP required to trigger purinergic receptor activation. Next, we examine evidence in the literature that the purinergic system accelerates AMD pathogenesis leading to apoptotic and pyroptotic cell death in retinal cells. To fully understand the potential role that purinergic signaling plays in AMD, more research is needed surrounding the expression, distribution, functions, and interactions of purinergic receptors within cells of the outer retina as well as potential crosstalk with other systems. By determining how these processes are affected in the context of purinergic signaling, it will improve our understanding of the mechanisms that drive AMD pathogenesis which is critical in developing treatment strategies that prevent or slow progression of the disease.
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Affiliation(s)
- Haydn Molcak
- Matsubara Lab, Faculty of Medicine, Department of Ophthalmology and Visual Sciences, Eye Care Centre, Vancouver, BC, Canada
| | - Kailun Jiang
- Matsubara Lab, Faculty of Medicine, Department of Ophthalmology and Visual Sciences, Eye Care Centre, Vancouver, BC, Canada
| | | | - Joanne A. Matsubara
- Matsubara Lab, Faculty of Medicine, Department of Ophthalmology and Visual Sciences, Eye Care Centre, Vancouver, BC, Canada
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Afarid M, Bahari H, Sanie-Jahromi F. In Vitro Evaluation of Apoptosis, Inflammation, Angiogenesis, and Neuroprotection Gene Expression in Retinal Pigmented Epithelial Cell Treated with Interferon α-2b. J Interferon Cytokine Res 2023. [PMID: 37289822 DOI: 10.1089/jir.2023.0028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023] Open
Abstract
Angiogenesis, retinal neuropathy, and inflammation are the main molecular features of diabetic retinopathy (DR) and should be taken into consideration for potential treatment approaches. Retinal pigmented epithelial (RPE) cells play a major role in DR progression. This study evaluated the in vitro effect of interferon (IFN) α-2b on the expression of genes involved in apoptosis, inflammation, neuroprotection, and angiogenesis in RPE cells. RPE cells were cocultured with IFN α-2b at 2 doses (500 and 1,000 IU) and treatment periods (24 and 48 h). The quantitative relative expression of genes (BCL-2, BAX, BDNF, VEGF, and IL-1b) was evaluated in the treated versus control cells through real-time polymerase chain reaction (PCR). The result of this study demonstrated that IFN treatment at 1,000 IU (48 h) led to significant upregulation of BCL-2, BAX, BDNF, and IL-1b; however, the BCL-2/BAX ratio was not statistically altered from 1:1, in any of the treatment patterns. We also showed that VEGF expression was downregulated in RPE cells treated with 500 IU for 24 h. It can be concluded that IFN α-2b was safe (BCL-2/BAX ∼1:1) and enhanced neuroprotection at 1,000 IU (48 h); however-at the same time-IFN α-2b induced inflammation in RPE cells. Moreover, the antiangiogenic effect of IFN α-2b was solely observed in RPE cells treated with 500 IU (24 h). It seems that IFN α-2b in lower doses and short duration exerts antiangiogenic effects and in higher doses and longer duration has neuroprotective and inflammatory effects. Hence, appropriate concentration and duration of treatment, according to the type and stage of the disease, should be considered to achieve success in IFN therapy.
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Affiliation(s)
- Mehrdad Afarid
- Poostchi Ophthalmology Research Center, Department of Ophthalmology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Hossein Bahari
- Poostchi Ophthalmology Research Center, Department of Ophthalmology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Fatemeh Sanie-Jahromi
- Poostchi Ophthalmology Research Center, Department of Ophthalmology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
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10
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P2X7 Is Involved in the Mouse Retinal Degeneration via the Coordinated Actions in Different Retinal Cell Types. Antioxidants (Basel) 2023; 12:antiox12010141. [PMID: 36671003 PMCID: PMC9854982 DOI: 10.3390/antiox12010141] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 01/02/2023] [Accepted: 01/03/2023] [Indexed: 01/11/2023] Open
Abstract
Adenosine triphosphate (ATP) released from dying cells with high concentrations is sensed as a danger signal by the P2X7 receptor. Sodium iodate (NaIO3) is an oxidative toxic agent, and its retinal toxicity has been used as the model of dry age-related macular degeneration (AMD). In this study, we used NaIO3-treated mice and cultured retinal cells, including BV-2 microglia, 661W photoreceptors, rMC1 Müller cells and ARPE-19 retinal epithelial cells, to understand the pathological action of P2X7 in retinal degeneration. We found that NaIO3 can significantly decrease the photoreceptor function by reducing a-wave and b-wave amplitudes in electroretinogram (ERG) analysis. Optical coherence tomography (OCT) analysis revealed the degeneration of retinal epithelium and ganglion cell layers. Interestingly, P2X7-/- mice were protected from the NaIO3-induced retinopathy and inflammatory NLRP3, IL-1β and IL-6 gene expression in the retina. Hematoxylin and eosin staining indicated that the retinal epithelium was less deteriorated in P2X7-/- mice compared to the WT group. Although P2X7 was barely detected in 661W, rMC1 and ARPE-19 cells, its gene and protein levels can be increased after NaIO3 treatment, leading to a synergistic cytotoxicity of BzATP [2'(3')-O-(4-benzoylbenzoyl)adenosine-5'-triphosphate tri(triethyleneammonium)salt] and NaIO3 administration in ARPE-19 cells. In conclusion, the paracrine action of the ATP/P2X7 axis via cell-cell communication is involved in NaIO3-induced retinal injury. Our results show that P2X7 antagonist might be a potential therapy in inflammation-related retinal degeneration.
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11
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Komiya Y, Takeyama A, Shibata M, Imamura Y, Ishida M. Outer retinal microstructure and visual function after macular hole surgery with and without Brilliant Blue G. Jpn J Ophthalmol 2022; 66:534-540. [PMID: 36181645 DOI: 10.1007/s10384-022-00942-z] [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: 03/10/2022] [Accepted: 07/21/2022] [Indexed: 12/14/2022]
Abstract
PURPOSE To evaluate the outer retinal microstructure and visual function after idiopathic macular hole (MH) surgery using internal limiting membrane (ILM) peeling with and without Brilliant Blue G (BBG) staining. STUDY DESIGN Retrospective, consecutive case series. METHODS A total of 49 eyes of 47 patients were enrolled: 23 eyes of 23 patients with MH who underwent ILM peeling without dyes (control group) and 26 eyes of 26 patients who underwent BBG staining (BBG group). The lengths of defects of the photoreceptor ellipsoid zone (EZ), external limiting membrane (ELM), and interdigitation zone (IZ) were measured. RESULTS The rate of MH closure after initial surgery was 95.6% (22/23 eyes) for the control group versus 100% (26/26 eyes) for the BBG group. In the 48 eyes with MH closure, the recovery rate of ELM deficiency and change in IZ deficiency showed no difference between the groups. The changes in EZ deficiency at 1 and 12 months were greater in the BBG group than in the control group. (P = 0.047 and 0.031). Visual acuity was better in the BBG group than in the control group during 12 months postoperatively (P < 0.001-0.038). CONCLUSION Eyes undergoing BBG-assisted MH surgery achieved faster recovery of the outer retinal structures and greater visual improvement than those of eyes without BBG.
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Affiliation(s)
- Yuko Komiya
- Department of Ophthalmology, Teikyo University School of Medicine, University Hospital Mizonokuchi, 5-1-1, Futago, Takatsu-ku, Kawasaki, Kanagawa, 213-8507, Japan
| | - Asuka Takeyama
- Department of Ophthalmology, Teikyo University School of Medicine, University Hospital Mizonokuchi, 5-1-1, Futago, Takatsu-ku, Kawasaki, Kanagawa, 213-8507, Japan. .,Department of Ophthalmology, Toho University Ohashi Medical Center, 2-22-36, Ohashi, Meguro-ku, Tokyo, 153-8515, Japan.
| | - Masaki Shibata
- Department of Ophthalmology, Teikyo University School of Medicine, University Hospital Mizonokuchi, 5-1-1, Futago, Takatsu-ku, Kawasaki, Kanagawa, 213-8507, Japan
| | - Yutaka Imamura
- Department of Ophthalmology, Teikyo University School of Medicine, University Hospital Mizonokuchi, 5-1-1, Futago, Takatsu-ku, Kawasaki, Kanagawa, 213-8507, Japan
| | - Masahiro Ishida
- Department of Ophthalmology, Teikyo University School of Medicine, University Hospital Mizonokuchi, 5-1-1, Futago, Takatsu-ku, Kawasaki, Kanagawa, 213-8507, Japan.,Department of Ophthalmology, Toho University Ohashi Medical Center, 2-22-36, Ohashi, Meguro-ku, Tokyo, 153-8515, Japan
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12
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Maggi MA, Consonni R, Cagliani LR, Prestipino G, Bisti S, Picco C. Saffron and retinal neurodegenerative diseases: Relevance of chemical composition. J Anat 2022. [PMID: 35778985 DOI: 10.1111/joa.13722] [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: 01/17/2022] [Revised: 05/19/2022] [Accepted: 06/15/2022] [Indexed: 11/29/2022] Open
Abstract
Saffron is an ancient spice largely used in traditional medicine. It has been found to be effective in treatment of retinal neurodegenerative diseases like age-related macular degeneration and Stargardt. In the present manuscript, it is shown that saffron's neuroprotective power is strongly related to the bioactivity of all its chemical components. Nuclear magnetic resonance spectroscopy and "in vitro" experiments confirm the relevance of crocins for saffron efficacy. These results underline the importance of strictly defining the chemical composition of the natural compounds in saffron to optimize their effectiveness in the treatment of diseases.
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Affiliation(s)
- Maria A Maggi
- Hortus Novus srl, Canistro, Italy.,Department of Physical and Chemical Sciences, University of L'Aquila, Coppito, Italy
| | - Roberto Consonni
- Lab. NMR, Institute of Chemical Sciences and Technologies "G. Natta" (SCITEC), National Research Council, Milan, Italy.,National Institute of Biostructure and Biosystem (INBB), Rome, Italy
| | - Laura R Cagliani
- Lab. NMR, Institute of Chemical Sciences and Technologies "G. Natta" (SCITEC), National Research Council, Milan, Italy
| | | | - Silvia Bisti
- National Institute of Biostructure and Biosystem (INBB), Rome, Italy.,Department of Biotecnology and Applied Clinical Sciences, DISCAB, University of L'Aquila, Coppito, Italy
| | - Cristiana Picco
- National Institute of Biostructure and Biosystem (INBB), Rome, Italy.,Institute of Biophysics (IBF), National Research Council, Genoa, Italy
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13
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Mahaling B, Low SWY, Beck M, Kumar D, Ahmed S, Connor TB, Ahmad B, Chaurasia SS. Damage-Associated Molecular Patterns (DAMPs) in Retinal Disorders. Int J Mol Sci 2022; 23:ijms23052591. [PMID: 35269741 PMCID: PMC8910759 DOI: 10.3390/ijms23052591] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Revised: 02/22/2022] [Accepted: 02/25/2022] [Indexed: 12/13/2022] Open
Abstract
Damage-associated molecular patterns (DAMPs) are endogenous danger molecules released from the extracellular and intracellular space of damaged tissue or dead cells. Recent evidence indicates that DAMPs are associated with the sterile inflammation caused by aging, increased ocular pressure, high glucose, oxidative stress, ischemia, mechanical trauma, stress, or environmental conditions, in retinal diseases. DAMPs activate the innate immune system, suggesting their role to be protective, but may promote pathological inflammation and angiogenesis in response to the chronic insult or injury. DAMPs are recognized by specialized innate immune receptors, such as receptors for advanced glycation end products (RAGE), toll-like receptors (TLRs) and the NOD-like receptor family (NLRs), and purine receptor 7 (P2X7), in systemic diseases. However, studies describing the role of DAMPs in retinal disorders are meager. Here, we extensively reviewed the role of DAMPs in retinal disorders, including endophthalmitis, uveitis, glaucoma, ocular cancer, ischemic retinopathies, diabetic retinopathy, age-related macular degeneration, rhegmatogenous retinal detachment, proliferative vitreoretinopathy, and inherited retinal disorders. Finally, we discussed DAMPs as biomarkers, therapeutic targets, and therapeutic agents for retinal disorders.
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Affiliation(s)
- Binapani Mahaling
- Ocular Immunology and Angiogenesis Lab, Department of Ophthalmology and Visual Sciences, Froedtert and MCW Eye Institute, Medical College of Wisconsin, Milwaukee, WI 53226, USA; (B.M.); (S.W.Y.L.); (M.B.); (D.K.); (S.A.); (T.B.C.); (B.A.)
| | - Shermaine W. Y. Low
- Ocular Immunology and Angiogenesis Lab, Department of Ophthalmology and Visual Sciences, Froedtert and MCW Eye Institute, Medical College of Wisconsin, Milwaukee, WI 53226, USA; (B.M.); (S.W.Y.L.); (M.B.); (D.K.); (S.A.); (T.B.C.); (B.A.)
| | - Molly Beck
- Ocular Immunology and Angiogenesis Lab, Department of Ophthalmology and Visual Sciences, Froedtert and MCW Eye Institute, Medical College of Wisconsin, Milwaukee, WI 53226, USA; (B.M.); (S.W.Y.L.); (M.B.); (D.K.); (S.A.); (T.B.C.); (B.A.)
| | - Devesh Kumar
- Ocular Immunology and Angiogenesis Lab, Department of Ophthalmology and Visual Sciences, Froedtert and MCW Eye Institute, Medical College of Wisconsin, Milwaukee, WI 53226, USA; (B.M.); (S.W.Y.L.); (M.B.); (D.K.); (S.A.); (T.B.C.); (B.A.)
| | - Simrah Ahmed
- Ocular Immunology and Angiogenesis Lab, Department of Ophthalmology and Visual Sciences, Froedtert and MCW Eye Institute, Medical College of Wisconsin, Milwaukee, WI 53226, USA; (B.M.); (S.W.Y.L.); (M.B.); (D.K.); (S.A.); (T.B.C.); (B.A.)
| | - Thomas B. Connor
- Ocular Immunology and Angiogenesis Lab, Department of Ophthalmology and Visual Sciences, Froedtert and MCW Eye Institute, Medical College of Wisconsin, Milwaukee, WI 53226, USA; (B.M.); (S.W.Y.L.); (M.B.); (D.K.); (S.A.); (T.B.C.); (B.A.)
- Vitreoretinal Surgery, Froedtert and MCW Eye Institute, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Baseer Ahmad
- Ocular Immunology and Angiogenesis Lab, Department of Ophthalmology and Visual Sciences, Froedtert and MCW Eye Institute, Medical College of Wisconsin, Milwaukee, WI 53226, USA; (B.M.); (S.W.Y.L.); (M.B.); (D.K.); (S.A.); (T.B.C.); (B.A.)
- Vitreoretinal Surgery, Froedtert and MCW Eye Institute, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Shyam S. Chaurasia
- Ocular Immunology and Angiogenesis Lab, Department of Ophthalmology and Visual Sciences, Froedtert and MCW Eye Institute, Medical College of Wisconsin, Milwaukee, WI 53226, USA; (B.M.); (S.W.Y.L.); (M.B.); (D.K.); (S.A.); (T.B.C.); (B.A.)
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, WI 53226, USA
- Correspondence: ; Tel.: +1-414-955-2050
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14
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Martínez-Alberquilla I, Gasull X, Pérez-Luna P, Seco-Mera R, Ruiz-Alcocer J, Crooke A. Neutrophils and neutrophil extracellular trap components: Emerging biomarkers and therapeutic targets for age-related eye diseases. Ageing Res Rev 2022; 74:101553. [PMID: 34971794 DOI: 10.1016/j.arr.2021.101553] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Revised: 11/17/2021] [Accepted: 12/23/2021] [Indexed: 12/14/2022]
Abstract
Age-related eye diseases, including dry eye, glaucoma, age-related macular degeneration, and diabetic retinopathy, represent a major global health issue based on their increasing prevalence and disabling action. Unraveling the molecular mechanisms underlying these diseases will provide novel opportunities to reduce the burden of age-related eye diseases and improve eye health, contributing to sustainable development goals achievement. The impairment of neutrophil extracellular traps formation/degradation processes seems to be one of these mechanisms. These traps formed by a meshwork of DNA and neutrophil cytosolic granule proteins may exacerbate the inflammatory response promoting chronic inflammation, a pivotal cause of age-related diseases. In this review, we describe current findings that suggest the role of neutrophils and their traps in the pathogenesis of the above-mentioned age-related eye diseases. Furthermore, we discuss why these cells and their constituents could be biomarkers and therapeutic targets for dry eye, glaucoma, age-related macular degeneration, and diabetic retinopathy. We also examine the therapeutic potential of some neutrophil function modulators and provide several recommendations for future research in age-related eye diseases.
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Affiliation(s)
- Irene Martínez-Alberquilla
- Department of Optometry and Vision, Faculty of Optics and Optometry, Universidad Complutense de Madrid, Madrid, Spain; Clinical and Experimental Eye Research Group, UCM 971009, Faculty of Optics and Optometry, Universidad Complutense de Madrid, Madrid, Spain
| | - Xavier Gasull
- Neurophysiology Laboratory, Department of Biomedicine, Medical School, Institute of Neurosciences, Universitat de Barcelona, Barcelona, Spain; Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | - Patricia Pérez-Luna
- Department of Biochemistry and Molecular Biology, Faculty of Optics and Optometry, Universidad Complutense de Madrid, Madrid, Spain
| | - Rubén Seco-Mera
- Department of Biochemistry and Molecular Biology, Faculty of Optics and Optometry, Universidad Complutense de Madrid, Madrid, Spain
| | - Javier Ruiz-Alcocer
- Department of Optometry and Vision, Faculty of Optics and Optometry, Universidad Complutense de Madrid, Madrid, Spain; Clinical and Experimental Eye Research Group, UCM 971009, Faculty of Optics and Optometry, Universidad Complutense de Madrid, Madrid, Spain
| | - Almudena Crooke
- Department of Biochemistry and Molecular Biology, Faculty of Optics and Optometry, Universidad Complutense de Madrid, Madrid, Spain; Clinical and Experimental Eye Research Group, UCM 971009, Faculty of Optics and Optometry, Universidad Complutense de Madrid, Madrid, Spain.
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15
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Markitantova YV, Simirskii VN. The Role of the Purinergic Signaling System in the Control of Histogenesis, Homeostasis, and Pathogenesis of the Vertebrate Retina. Russ J Dev Biol 2021. [DOI: 10.1134/s1062360421060084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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16
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Zeng R, Du L, Chen L. Long-term observation of outer retinopathy-like sequelae in intrapapillary hemorrhage with adjacent peripapillary subretinal hemorrhage using multimodal imaging. ADVANCES IN OPHTHALMOLOGY PRACTICE AND RESEARCH 2021; 1:100009. [PMID: 37846391 PMCID: PMC10577860 DOI: 10.1016/j.aopr.2021.100009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/12/2021] [Revised: 10/08/2021] [Accepted: 10/20/2021] [Indexed: 10/18/2023]
Affiliation(s)
- Renpan Zeng
- Department of Ophthalmology, Sichuan Provincial Corps Hospital, Chinese People's Armed Police Forces, Leshan, 614000, China
| | - Lixia Du
- Department of Ophthalmology, Sichuan Provincial Corps Hospital, Chinese People's Armed Police Forces, Leshan, 614000, China
| | - Li Chen
- Department of Ophthalmology, Sichuan Provincial Corps Hospital, Chinese People's Armed Police Forces, Leshan, 614000, China
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17
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Campagno KE, Lu W, Jassim AH, Albalawi F, Cenaj A, Tso HY, Clark SP, Sripinun P, Gómez NM, Mitchell CH. Rapid morphologic changes to microglial cells and upregulation of mixed microglial activation state markers induced by P2X7 receptor stimulation and increased intraocular pressure. J Neuroinflammation 2021; 18:217. [PMID: 34544431 PMCID: PMC8454080 DOI: 10.1186/s12974-021-02251-7] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Accepted: 08/25/2021] [Indexed: 01/16/2023] Open
Abstract
BACKGROUND The identification of endogenous signals that lead to microglial activation is a key step in understanding neuroinflammatory cascades. As ATP release accompanies mechanical strain to neural tissue, and as the P2X7 receptor for ATP is expressed on microglial cells, we examined the morphological and molecular consequences of P2X7 receptor stimulation in vivo and in vitro and investigated the contribution of the P2X7 receptor in a model of increased intraocular pressure (IOP). METHODS In vivo experiments involved intravitreal injections and both transient and sustained elevation of IOP. In vitro experiments were performed on isolated mouse retinal and brain microglial cells. Morphological changes were quantified in vivo using Sholl analysis. Expression of mRNA for M1- and M2-like genes was determined with qPCR. The luciferin/luciferase assay quantified retinal ATP release while fura-2 indicated cytoplasmic calcium. Microglial migration was monitored with a Boyden chamber. RESULTS Sholl analysis of Iba1-stained cells showed retraction of microglial ramifications 1 day after injection of P2X7 receptor agonist BzATP into mouse retinae. Mean branch length of ramifications also decreased, while cell body size and expression of Nos2, Tnfa, Arg1, and Chil3 mRNA increased. BzATP induced similar morphological changes in ex vivo tissue isolated from Cx3CR1+/GFP mice, suggesting recruitment of external cells was unnecessary. Immunohistochemistry suggested primary microglial cultures expressed the P2X7 receptor, while functional expression was demonstrated with Ca2+ elevation by BzATP and block by specific antagonist A839977. BzATP induced process retraction and cell body enlargement within minutes in isolated microglial cells and increased Nos2 and Arg1. While ATP increased microglial migration, this required the P2Y12 receptor and not P2X7 receptor. Transient elevation of IOP led to microglial process retraction, cell body enlargement, and gene upregulation paralleling changes observed with BzATP injection, in addition to retinal ATP release. Pressure-dependent changes were reduced in P2X7-/- mice. Death of retinal ganglion cells accompanied increased IOP in C57Bl/6J, but not P2X7-/- mice, and neuronal loss showed some association with microglial activation. CONCLUSIONS P2X7 receptor stimulation induced rapid morphological activation of microglial cells, including process retraction and cell body enlargement, and upregulation of markers linked to both M1- and M2-type activation. Parallel responses accompanied IOP elevation, suggesting ATP release and P2X7 receptor stimulation influence the early microglial response to increased pressure.
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Affiliation(s)
- Keith E Campagno
- Department of Basic and Translational Science, University of Pennsylvania, 240 S. 40th St, Philadelphia, PA, 19104, USA
| | - Wennan Lu
- Department of Basic and Translational Science, University of Pennsylvania, 240 S. 40th St, Philadelphia, PA, 19104, USA
| | - Assraa Hassan Jassim
- Department of Basic and Translational Science, University of Pennsylvania, 240 S. 40th St, Philadelphia, PA, 19104, USA
| | - Farraj Albalawi
- Department of Orthodontics, University of Pennsylvania, Philadelphia, PA, 19104, USA
- Department of Preventive Dental Sciences, College of Dentistry, King Saud bin Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia
- King Abdullah International Medical Research Center, Riyadh, Saudi Arabia
| | - Aurora Cenaj
- Department of Basic and Translational Science, University of Pennsylvania, 240 S. 40th St, Philadelphia, PA, 19104, USA
| | - Huen-Yee Tso
- Department of Basic and Translational Science, University of Pennsylvania, 240 S. 40th St, Philadelphia, PA, 19104, USA
| | - Sophia P Clark
- Department of Basic and Translational Science, University of Pennsylvania, 240 S. 40th St, Philadelphia, PA, 19104, USA
| | - Puttipong Sripinun
- Department of Orthodontics, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Néstor Más Gómez
- Department of Basic and Translational Science, University of Pennsylvania, 240 S. 40th St, Philadelphia, PA, 19104, USA
| | - Claire H Mitchell
- Department of Basic and Translational Science, University of Pennsylvania, 240 S. 40th St, Philadelphia, PA, 19104, USA.
- Department of Ophthalmology, University of Pennsylvania, Philadelphia, PA, 19104, USA.
- Department of Physiology, University of Pennsylvania, Philadelphia, PA, 19104, USA.
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18
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Ye SS, Tang Y, Song JT. ATP and Adenosine in the Retina and Retinal Diseases. Front Pharmacol 2021; 12:654445. [PMID: 34211393 PMCID: PMC8239296 DOI: 10.3389/fphar.2021.654445] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2021] [Accepted: 05/25/2021] [Indexed: 12/11/2022] Open
Abstract
Extracellular ATP and its ultimate degradation product adenosine are potent extracellular signaling molecules that elicit a variety of pathophysiological pathways in retina through the activation of P2 and P1 purinoceptors, respectively. Excessive build-up of extracellular ATP accelerates pathologic responses in retinal diseases, whereas accumulation of adenosine protects retinal cells against degeneration or inflammation. This mini-review focuses on the roles of ATP and adenosine in three types of blinding diseases including age-related macular degeneration (AMD), glaucoma, and diabetic retinopathy (DR). Several agonists and antagonists of ATP receptors and adenosine receptors (ARs) have been developed for the potential treatment of glaucoma, DR and AMD: antagonists of P2X7 receptor (P2X7R) (BBG, MRS2540) prevent ATP-induced neuronal apoptosis in glaucoma, DR, and AMD; A1 receptor (A1R) agonists (INO-8875) lower intraocular pressure in glaucoma; A2A receptor (A2AR) agonists (CGS21680) or antagonists (SCH58261, ZM241385) reduce neuroinflammation in glaucoma, DR, and AMD; A3 receptor (A3R) agonists (2-Cl-lB-MECA, MRS3558) protect retinal ganglion cells (RGCs) from apoptosis in glaucoma.
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Affiliation(s)
- Shan-Shan Ye
- Eye Hospital, China Academy of Chinese Medical Sciences, Beijing, China
| | - Yong Tang
- International Collaborative Centre on Big Science Plan for Purinergic Signalling, Chengdu University of Traditional Chinese Medicine, Chengdu, China.,Acupuncture and Chronobiology Key Laboratory of Sichuan Province, Chengdu, China
| | - Jian-Tao Song
- Eye Hospital, China Academy of Chinese Medical Sciences, Beijing, China
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19
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Calzaferri F, Ruiz-Ruiz C, de Diego AMG, de Pascual R, Méndez-López I, Cano-Abad MF, Maneu V, de Los Ríos C, Gandía L, García AG. The purinergic P2X7 receptor as a potential drug target to combat neuroinflammation in neurodegenerative diseases. Med Res Rev 2020; 40:2427-2465. [PMID: 32677086 DOI: 10.1002/med.21710] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Revised: 06/22/2020] [Accepted: 06/27/2020] [Indexed: 12/25/2022]
Abstract
Neurodegenerative diseases (NDDs) represent a huge social burden, particularly in Alzheimer's disease (AD) in which all proposed treatments investigated in murine models have failed during clinical trials (CTs). Thus, novel therapeutic strategies remain crucial. Neuroinflammation is a common pathogenic feature of NDDs. As purinergic P2X7 receptors (P2X7Rs) are gatekeepers of inflammation, they could be developed as drug targets for NDDs. Herein, we review this challenging hypothesis and comment on the numerous studies that have investigated P2X7Rs, emphasizing their molecular structure and functions, as well as their role in inflammation. Then, we elaborate on research undertaken in the field of medicinal chemistry to determine potential P2X7R antagonists. Subsequently, we review the state of neuroinflammation and P2X7R expression in the brain, in animal models and patients suffering from AD, Parkinson's disease, amyotrophic lateral sclerosis, Huntington's disease, multiple sclerosis, and retinal degeneration. Next, we summarize the in vivo studies testing the hypothesis that by mitigating neuroinflammation, P2X7R blockers afford neuroprotection, increasing neuroplasticity and neuronal repair in animal models of NDDs. Finally, we reviewed previous and ongoing CTs investigating compounds directed toward targets associated with NDDs; we propose that CTs with P2X7R antagonists should be initiated. Despite the high expectations for putative P2X7Rs antagonists in various central nervous system diseases, the field is moving forward at a relatively slow pace, presumably due to the complexity of P2X7Rs. A better pharmacological approach to combat NDDs would be a dual strategy, combining P2X7R antagonism with drugs targeting a selective pathway in a given NDD.
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Affiliation(s)
- Francesco Calzaferri
- Departamento de Farmacología, Instituto-Fundación Teófilo Hernando, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
| | - Cristina Ruiz-Ruiz
- Departamento de Farmacología, Instituto-Fundación Teófilo Hernando, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
| | - Antonio M G de Diego
- Departamento de Farmacología, Instituto-Fundación Teófilo Hernando, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain.,Instituto de Investigación Sanitaria, Hospital Universitario de La Princesa, Universidad Autónoma de Madrid, Madrid, Spain
| | - Ricardo de Pascual
- Departamento de Farmacología, Instituto-Fundación Teófilo Hernando, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
| | - Iago Méndez-López
- Departamento de Farmacología, Instituto-Fundación Teófilo Hernando, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
| | - María F Cano-Abad
- Departamento de Farmacología, Instituto-Fundación Teófilo Hernando, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain.,Instituto de Investigación Sanitaria, Hospital Universitario de La Princesa, Universidad Autónoma de Madrid, Madrid, Spain
| | - Victoria Maneu
- Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante, San Vicente del Raspeig, Spain
| | - Cristóbal de Los Ríos
- Departamento de Farmacología, Instituto-Fundación Teófilo Hernando, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain.,Instituto de Investigación Sanitaria, Hospital Universitario de La Princesa, Universidad Autónoma de Madrid, Madrid, Spain
| | - Luis Gandía
- Departamento de Farmacología, Instituto-Fundación Teófilo Hernando, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
| | - Antonio G García
- Departamento de Farmacología, Instituto-Fundación Teófilo Hernando, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain.,Instituto de Investigación Sanitaria, Hospital Universitario de La Princesa, Universidad Autónoma de Madrid, Madrid, Spain
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20
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Farjood F, Ahmadpour A, Ostvar S, Vargis E. Acute mechanical stress in primary porcine RPE cells induces angiogenic factor expression and in vitro angiogenesis. J Biol Eng 2020; 14:13. [PMID: 32355505 PMCID: PMC7183714 DOI: 10.1186/s13036-020-00235-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2020] [Accepted: 03/24/2020] [Indexed: 12/21/2022] Open
Abstract
Background Choroidal neovascularization (CNV) is a major cause of blindness in patients with age-related macular degeneration. CNV is characterized by new blood vessel growth and subretinal fluid accumulation, which results in mechanical pressure on retinal pigment epithelial (RPE) cells. The overexpression of RPE-derived angiogenic factors plays an important role in inducing CNV. In this work, we investigated the effect of mechanical stress on the expression of angiogenic factors in porcine RPE cells and determined the impact of conditioned medium on in-vitro angiogenesis. Results The goal of this study was to determine whether low levels of acute mechanical stress during early CNV can induce the expression of angiogenic factors in RPE cells and accelerate angiogenesis. Using a novel device, acute mechanical stress was applied to primary porcine RPE cells and the resulting changes in the expression of major angiogenic factors, VEGF, ANG2, HIF-1α, IL6, IL8 and TNF-α, were examined using immunocytochemistry, qRT-PCR, and ELISA. An in vitro tube formation assay was used to determine the effect of secreted angiogenic proteins due to mechanical stress on endothelial tube formation by human umbilical vein endothelial cells (HUVECs). Our results showed an increase in the expression of VEGF, ANG2, IL-6 and IL-8 in response to mechanical stress, resulting in increased in vitro angiogenesis. Abnormal epithelial-mesenchymal transition (EMT) in RPE cells is also associated with CNV and further retinal degeneration. Our qRT-PCR results verified an increase in the expression of EMT genes, CDH2, VIM and FN1, in RPE cells. Conclusions In conclusion, we showed that acute mechanical stress induces the expression of major angiogenic and EMT factors and promotes in vitro angiogenesis, suggesting that mechanical stress plays a role in promoting aberrant angiogenesis in AMD.
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Affiliation(s)
- Farhad Farjood
- 1Department of Biological Engineering, Utah State University, 4105 Old Main Hill, Logan, UT 84322 USA.,2Present address: Neural Stem Cell Institute, Rensselaer, NY 12144 USA
| | - Amir Ahmadpour
- 1Department of Biological Engineering, Utah State University, 4105 Old Main Hill, Logan, UT 84322 USA.,3Present address: Department of Animal Sciences, Yasouj University, Yasouj, 75918-74934 Iran
| | - Sassan Ostvar
- 4Division of General Medicine, Columbia University Medical Center, New York, NY 10032 USA
| | - Elizabeth Vargis
- 1Department of Biological Engineering, Utah State University, 4105 Old Main Hill, Logan, UT 84322 USA
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21
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Long-term Clinical Course after Vitrectomy for Breakthrough Vitreous Hemorrhage Secondary to Neovascular Age-related Macular Degeneration and Polypoidal Choroidal Vasculopathy. Sci Rep 2020; 10:359. [PMID: 31941971 PMCID: PMC6962336 DOI: 10.1038/s41598-019-57297-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Accepted: 12/10/2019] [Indexed: 11/21/2022] Open
Abstract
To investigate the long-term clinical course after vitrectomy for breakthrough vitreous hemorrhage secondary to neovascular age-related macular degeneration (AMD) and polypoidal choroidal vasculopathy (PCV). This retrospective study included 45 eyes that underwent vitrectomy due to breakthrough vitreous hemorrhage secondary to neovascular AMD. The patients were divided into 2 groups: neovascular AMD group and PCV group. Within each group, the status of the eye within 6 months after the surgery and that at the final follow-up was identified. The visual acuity at the final visit was additionally compared between the 2 groups. The patients were followed up for a mean period of 39.9 ± 19.4 months after the surgery. In the neovascular AMD group (n = 17), re-bleeding requiring vitrectomy was noted in 4 eyes and extensive scar formation was noted in 6 eyes within 6 months after the surgery. At the final visit, treatment was discontinued due to poor visual outcome in 10 eyes. In the PCV group (n = 28), re-bleeding requiring vitrectomy was noted in 1 eye, and extensive scar formation was noted in 4 eyes within 6 months after the surgery. At the final visit, treatment was discontinued in 8 eyes. The visual acuity at the final visit was significantly better in the PCV group (P = 0.003). The long-term clinical course after vitrectomy for breakthrough vitreous hemorrhage was markedly different between neovascular AMD and PCV, showing significantly better long-term visual outcomes in PCV.
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22
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Abstract
Adenylate kinase is a small, usually monomeric, enzyme found in every living thing due to its crucial role in energetic metabolism. This paper outlines the most relevant data about adenylate kinases isoforms, and the connection between dysregulation or mutation of human adenylate kinase and medical conditions. The following datadases were consulted: National Centre for Biotechnology Information, Protein Data Bank, and Mouse Genomic Informatics. The SmartBLAST tool, EMBOSS Needle Program, and Clustal Omega Program were used to analyze the best protein match, and to perform pairwise sequence alignment and multiple sequence alignment. Human adenylate kinase genes are located on different chromosomes, six of them being on the chromosomes 1 and 9. The adenylate kinases' intracellular localization and organ distribution explain their dysregulation in many diseases. The cytosolic isoenzyme 1 and the mitochondrial isoenzyme 2 are the main adenylate kinases that are integrated in the vast network of inflammatory modulators. The cytosolic isoenzyme 5 is correlated with limbic encephalitis and Leu673Pro mutation of the isoenzyme 7 leads to primary male infertility due to impairment of the ciliary function. The impairment of the mitochondrial isoenzymes 2 and 4 is demonstrated in neuroblastoma or glioma. The adenylate kinases are disease modifier that can assess the risk of diseases where oxidative stress plays a crucial role in pathogenesis like metabolic syndrome or neurodegenerative diseases. Because adenylate kinases has ATP as substrate, they are integrated in the global network of energetic process of any organism therefore are valid target for new pharmaceutical compounds.
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Affiliation(s)
- Mihaela Ileana Ionescu
- Department of Microbiology, Faculty of Medicine, Iuliu Haţieganu University of Medicine and Pharmacy, 6 Louis Pasteur, Cluj-Napoca, 400349, Romania. .,County Emergency Clinical Hospital, Cluj-Napoca, Romania.
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23
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Effect of Ocular Hypertension on D- β-Aspartic Acid-Containing Proteins in the Retinas of Rats. J Ophthalmol 2019; 2019:2431481. [PMID: 31240134 PMCID: PMC6556240 DOI: 10.1155/2019/2431481] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Revised: 03/28/2019] [Accepted: 05/07/2019] [Indexed: 12/31/2022] Open
Abstract
Purpose To investigate the effect of ocular hypertension-induced isomerization of aspartic acid in retinal proteins. Methods Adult Wistar rats with ocular hypertension were used as an experimental model. D-β-aspartic acid-containing proteins were isolated by SDS-PAGE and western blot with an anti-D-β-aspartic acid antibody and identified by liquid chromatography-mass spectrometry analysis. The concentration of ATP was measured by ELISA. Results D-β-aspartic acid was expressed in a protein band at around 44.5 kDa at much higher quantities in the retinas of rats with ocular hypertension than in those of normotensive rats. The 44.5 kDa protein band was mainly composed of α-enolase, S-arrestin, and ATP synthase subunits α and β, in both the ocular hypertensive and normotensive retinas. Moreover, increasing intraocular pressure was correlated with increasing ATP concentrations in the retinas of rats. Conclusion Ocular hypertension affected the expression of proteins containing D-β-aspartic acid, including ATP synthase subunits, and up-regulation of ATP in the retinas of rats.
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Fletcher EL, Wang AY, Jobling AI, Rutar MV, Greferath U, Gu B, Vessey KA. Targeting P2X7 receptors as a means for treating retinal disease. Drug Discov Today 2019; 24:1598-1605. [PMID: 30954685 DOI: 10.1016/j.drudis.2019.03.029] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Revised: 03/07/2019] [Accepted: 03/29/2019] [Indexed: 12/28/2022]
Abstract
Age-related macular degeneration and glaucoma are the commonest causes of irreversible vision loss in industrialized countries. The purine ATP is known to regulate a range of cellular functions in the retina via its action on P2 receptors, especially the P2X7 receptor. Although agents that attenuate P2X7 receptor function have been in development for many years, no compound is currently approved for the treatment of eye disease. However, newer compounds that cross the blood-brain barrier could have potential to reduce vision loss. This review will outline recent information relating to the role of P2X7 in age-related macular degeneration and glaucoma and, subsequently, we will discuss recent developments for attenuating P2X7 receptor function.
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Affiliation(s)
- Erica L Fletcher
- Department of Anatomy and Neuroscience, The University of Melbourne, Parkville 3010, Victoria, Australia.
| | - Anna Y Wang
- Department of Anatomy and Neuroscience, The University of Melbourne, Parkville 3010, Victoria, Australia
| | - Andrew I Jobling
- Department of Anatomy and Neuroscience, The University of Melbourne, Parkville 3010, Victoria, Australia
| | - Matthew V Rutar
- Department of Anatomy and Neuroscience, The University of Melbourne, Parkville 3010, Victoria, Australia
| | - Ursula Greferath
- Department of Anatomy and Neuroscience, The University of Melbourne, Parkville 3010, Victoria, Australia
| | - Ben Gu
- Florey Institute of Neuroscience and Mental Health, Parkville 3010, Victoria, Australia
| | - Kirstan A Vessey
- Department of Anatomy and Neuroscience, The University of Melbourne, Parkville 3010, Victoria, Australia
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Wang L, Schmidt S, Larsen PP, Meyer JH, Roush WR, Latz E, Holz FG, Krohne TU. Efficacy of novel selective NLRP3 inhibitors in human and murine retinal pigment epithelial cells. J Mol Med (Berl) 2019; 97:523-532. [DOI: 10.1007/s00109-019-01753-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2018] [Revised: 01/10/2019] [Accepted: 01/29/2019] [Indexed: 12/28/2022]
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Soluble and membrane-bound adenylate kinase and nucleotidases augment ATP-mediated inflammation in diabetic retinopathy eyes with vitreous hemorrhage. J Mol Med (Berl) 2019; 97:341-354. [PMID: 30617853 PMCID: PMC6394560 DOI: 10.1007/s00109-018-01734-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Revised: 11/23/2018] [Accepted: 12/17/2018] [Indexed: 12/28/2022]
Abstract
Abstract ATP and adenosine are important signaling molecules involved in vascular remodeling, retinal function, and neurovascular coupling in the eye. Current knowledge on enzymatic pathways governing the duration and magnitude of ocular purinergic signaling is incompletely understood. By employing sensitive analytical assays, this study dissected ocular purine homeostasis as a complex and coordinated network. Along with previously characterized ecto-5′-nucleotidase/CD73 and adenylate kinase activities, other enzymes have been identified in vitreous fluids, including nucleoside triphosphate diphosphohydrolase (NTPDase), adenosine deaminase, and alkaline phosphatase. Strikingly, activities of soluble adenylate kinase, adenosine deaminase, ecto-5′-nucleotidase/CD73, and alkaline phosphatase, as well as intravitreal concentrations of ATP and ADP, were concurrently upregulated in patients suffering from diabetic retinopathy (DR) with non-clearing vitreous hemorrhage (VH), when compared to DR eyes without VH and control eyes operated due to macular hole or pucker. Additional histochemical analysis revealed selective distribution of key ecto-nucleotidases (NTPDase1/CD39, NTPDase2, ecto-5′-nucleotidase/CD73, and alkaline phosphatase) in the human sensory neuroretina and optic nerve head, and also in pathological neofibrovascular tissues surgically excised from patients with advanced proliferative DR. Collectively, these data provide evidence for specific hemorrhage-related shifts in purine homeostasis in DR eyes from the generation of anti-inflammatory adenosine towards a pro-inflammatory and pro-angiogenic ATP-regenerating phenotype. In the future, identifying the exact mechanisms by which a broad spectrum of soluble and membrane-bound enzymes coordinately regulates ocular purine levels and the further translation of purine-converting enzymes as potential therapeutic targets in the treatment of proliferative DR and other vitreoretinal diseases will be an area of intense interest. Key messages NTPDase, alkaline phosphatase, and adenosine deaminase circulate in human vitreous. Purinergic enzymes are up-regulated in diabetic eyes with vitreous hemorrhage. Soluble adenylate kinase maintains high ATP levels in diabetic retinopathy eyes. Ecto-nucleotidases are co-expressed in the human retina and optic nerve head. Alkaline phosphatase is expressed on neovascular tissues excised from diabetic eyes.
Electronic supplementary material The online version of this article (10.1007/s00109-018-01734-0) contains supplementary material, which is available to authorized users.
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Zhao H, Chen Y, Feng H. P2X7 Receptor-Associated Programmed Cell Death in the Pathophysiology of Hemorrhagic Stroke. Curr Neuropharmacol 2018; 16:1282-1295. [PMID: 29766811 PMCID: PMC6251042 DOI: 10.2174/1570159x16666180516094500] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2017] [Revised: 07/17/2017] [Accepted: 02/28/2018] [Indexed: 12/20/2022] Open
Abstract
Hemorrhagic stroke is a life-threatening disease characterized by a sudden rupture of cerebral blood vessels, and cell death is widely believed to occur after exposure to blood metabolites or subsequently damaged cells. Recently, programmed cell death, such as apoptosis, autophagy, necroptosis, pyroptosis, and ferroptosis, has been demonstrated to play crucial roles in the pathophysiology of stroke. However, the detailed mechanisms of these novel kinds of cell death are still unclear. The P2X7 receptor, previously known for its cytotoxic activity, is an ATP-gated, nonselective cation channel that belongs to the family of ionotropic P2X receptors. Evolving evidence indicates that the P2X7 receptor plays a pivotal role in central nervous system pathology; genetic deletion and pharmacological blockade of the P2X7 receptor provide neuroprotection in various neurological disorders, including intracerebral hemorrhage and subarachnoid hemorrhage. The P2X7 receptor may regulate programmed cell death via (I) exocytosis of secretory lysosomes, (II) exocytosis of autophagosomes or autophagolysosomes during formation of the initial autophagic isolation membrane or omegasome, and (III) direct release of cytosolic IL-1β secondary to regulated cell death by pyroptosis or necroptosis. In this review, we present an overview of P2X7 receptor- associated programmed cell death for further understanding of hemorrhagic stroke pathophysiology, as well as potential therapeutic targets for its treatment.
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Affiliation(s)
- Hengli Zhao
- Department of Neurosurgery, Southwest Hospital, Third Military Medical University, Chongqing, China
| | - Yujie Chen
- Department of Neurosurgery, Southwest Hospital, Third Military Medical University, Chongqing, China
| | - Hua Feng
- Department of Neurosurgery, Southwest Hospital, Third Military Medical University, Chongqing, China
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Ventura ALM, Dos Santos-Rodrigues A, Mitchell CH, Faillace MP. Purinergic signaling in the retina: From development to disease. Brain Res Bull 2018; 151:92-108. [PMID: 30458250 DOI: 10.1016/j.brainresbull.2018.10.016] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Revised: 09/14/2018] [Accepted: 10/23/2018] [Indexed: 02/07/2023]
Abstract
Retinal injuries and diseases are major causes of human disability involving vision impairment by the progressive and permanent loss of retinal neurons. During development, assembly of this tissue entails a successive and overlapping, signal-regulated engagement of complex events that include proliferation of progenitors, neurogenesis, cell death, neurochemical differentiation and synaptogenesis. During retinal damage, several of these events are re-activated with both protective and detrimental consequences. Purines and pyrimidines, along with their metabolites are emerging as important molecules regulating both retinal development and the tissue's responses to damage. The present review provides an overview of the purinergic signaling in the developing and injured retina. Recent findings on the presence of vesicular and channel-mediated ATP release by retinal and retinal pigment epithelial cells, adenosine synthesis and release, expression of receptors and intracellular signaling pathways activated by purinergic signaling in retinal cells are reported. The pathways by which purinergic receptors modulate retinal cell proliferation, migration and death of retinal cells during development and injury are summarized. The contribution of nucleotides to the self-repair of the injured zebrafish retina is also discussed.
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Affiliation(s)
- Ana Lucia Marques Ventura
- Department of Neurobiology, Neuroscience Program, Fluminense Federal University, Niterói, RJ, Brazil.
| | | | - Claire H Mitchell
- Department of Anatomy and Cell Biology, Ophthalmology, and Physiology, University of Pennsylvania, Philadelphia, PA 19104, United States.
| | - Maria Paula Faillace
- Instituto de Fisiología y Biofísica Prof. Bernardo Houssay (IFIBIO-Houssay), Universidad de Buenos Aires y Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina; Departamento de Fisiología, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina.
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Kim JH, Chang YS, Kim JW, Kim CG, Lee DW. Early Recurrent Hemorrhage in Submacular Hemorrhage Secondary to Type 3 Neovascularization or Retinal Angiomatous Proliferation: Incidence and Influence on Visual Prognosis. Semin Ophthalmol 2018; 33:820-828. [DOI: 10.1080/08820538.2018.1511814] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Jae Hui Kim
- Department of Ophthalmology, Kim’s Eye Hospital, Konyang University College of Medicine, Seoul, South Korea
| | - Young Suk Chang
- Department of Ophthalmology, Konyang University College of Medicine, Daejeon, South Korea
| | - Jong Woo Kim
- Department of Ophthalmology, Kim’s Eye Hospital, Konyang University College of Medicine, Seoul, South Korea
| | - Chul Gu Kim
- Department of Ophthalmology, Kim’s Eye Hospital, Konyang University College of Medicine, Seoul, South Korea
| | - Dong Won Lee
- Department of Ophthalmology, Kim’s Eye Hospital, Konyang University College of Medicine, Seoul, South Korea
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Tochitsky I, Kienzler MA, Isacoff E, Kramer RH. Restoring Vision to the Blind with Chemical Photoswitches. Chem Rev 2018; 118:10748-10773. [PMID: 29874052 DOI: 10.1021/acs.chemrev.7b00723] [Citation(s) in RCA: 89] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Degenerative retinal diseases such as retinitis pigmentosa (RP) and age-related macular degeneration (AMD) affect millions of people around the world and lead to irreversible vision loss if left untreated. A number of therapeutic strategies have been developed over the years to treat these diseases or restore vision to already blind patients. In this Review, we describe the development and translational application of light-sensitive chemical photoswitches to restore visual function to the blind retina and compare the translational potential of photoswitches with other vision-restoring therapies. This therapeutic strategy is enabled by an efficient fusion of chemical synthesis, chemical biology, and molecular biology and is broadly applicable to other biological systems. We hope this Review will be of interest to chemists as well as neuroscientists and clinicians.
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Affiliation(s)
- Ivan Tochitsky
- F.M. Kirby Neurobiology Center , Boston Children's Hospital , Boston , Massachusetts 02115 , United States.,Department of Neurobiology , Harvard Medical School , Boston , Massachusetts 02115 , United States
| | - Michael A Kienzler
- Department of Chemistry , University of Maine , Orono , Maine 04469 , United States
| | - Ehud Isacoff
- Department of Molecular and Cell Biology , University of California , Berkeley , California 94720 , United States.,Helen Wills Neuroscience Institute , University of California , Berkeley , California 94720 , United States.,Bioscience Division , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , United States
| | - Richard H Kramer
- Department of Molecular and Cell Biology , University of California , Berkeley , California 94720 , United States.,Helen Wills Neuroscience Institute , University of California , Berkeley , California 94720 , United States
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Iijima H. Mechanisms of vision loss in eyes with macular edema associated with retinal vein occlusion. Jpn J Ophthalmol 2018; 62:265-273. [PMID: 29572577 DOI: 10.1007/s10384-018-0586-5] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2017] [Accepted: 03/05/2018] [Indexed: 11/24/2022]
Abstract
Anti-vascular endothelial growth factor agents reduce macular edema and improve vision in eyes with macular edema associated with retinal vein occlusion (RVO), including branch RVO (BRVO) and central RVO. However, not all eyes with resolved macular edema show satisfactory best corrected visual acuity. Photoreceptor impairment can mostly explain the vision loss in these cases. Photoreceptor damage can be caused by subretinal hemorrhage in the central fovea and hard exudates or their precursor derived from concentrated lipoproteins originating from leaky retinal vessel extravasation. The contribution of neuron impairment in the inner retina, including the impairment of bipolar and ganglion cells by ischemia, indicated by the presence of a non-perfusion area (NPA), to vision loss in eyes with BRVO is insignificant. This is because the papillomacular bundle area is usually spared from NPAs in BRVO cases.
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Affiliation(s)
- Hiroyuki Iijima
- Department of Ophthalmology, University of Yamanashi, 1110 Shimokato, Chuo, Yamanashi, 409-3898, Japan.
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Kim JH, Chang YS, Kim CG, Lee DW, Han JI. Hyperpigmented spots after treatment for submacular hemorrhage secondary to polypoidal choroidal vasculopathy. Graefes Arch Clin Exp Ophthalmol 2018; 256:469-477. [DOI: 10.1007/s00417-017-3877-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2017] [Revised: 12/05/2017] [Accepted: 12/12/2017] [Indexed: 11/28/2022] Open
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Kim JH, Chang YS, Lee DW, Kim CG, Kim JW. Quantification of retinal changes after resolution of submacular hemorrhage secondary to polypoidal choroidal vasculopathy. Jpn J Ophthalmol 2017; 62:54-62. [PMID: 29188462 DOI: 10.1007/s10384-017-0549-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2017] [Accepted: 10/26/2017] [Indexed: 01/09/2023]
Abstract
PURPOSE To evaluate changes in the thickness of retinal layers after resolution of submacular hemorrhage secondary to polypoidal choroidal vasculopathy (PCV). STUDY DESIGN Retrospective, observational study. METHODS This study included 21 patients (21 eyes) who had been diagnosed with submacular hemorrhage secondary to PCV and treated using anti-vascular endothelial growth factor monotherapy. After the hemorrhage had resolved, the thicknesses of the retinal layers were measured on horizontal- and vertical-crosshair optical coherence tomography scan images. The thickness of each layer in the region affected by the hemorrhage was compared with the thickness of the layer in the corresponding region in the fellow eye, as well as between an unaffected region in the eye with the hemorrhage and the corresponding region in the fellow eye. RESULTS Optical coherence tomography (OCT) was performed 5.5±2.8 months after diagnosis. In the horizontal OCT images, the outer plexiform layer (OPL) and outer nuclear layer (ONL) + photoreceptor layer (PRL) were significantly thinner in the affected region than in the corresponding region (P = 0.019 and P <0.001, respectively). In the vertical OCT image, the ONL+PRL was significantly thinner in the affected region than in the corresponding region (P <0.001). The thickness of the retinal layer in the unaffected region did not differ from that in the corresponding region of the fellow eye. CONCLUSIONS The significant thinning of the outer retinal layers in the regions affected by submacular hemorrhage suggests that the hemorrhage induces marked damage in the outer retinal layers, explaining the poor visual prognosis of submacular hemorrhage.
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Affiliation(s)
- Jae Hui Kim
- Department of Ophthalmology, Kim's Eye Hospital, Konyang University College of Medicine, #156 Youngdeungpo-dong 4ga, Youngdeungpo-gu, Seoul, 150-034, South Korea.
| | - Young Suk Chang
- Department of Ophthalmology, Konyang University College of Medicine, Daejeon, South Korea
| | - Dong Won Lee
- Department of Ophthalmology, Kim's Eye Hospital, Konyang University College of Medicine, #156 Youngdeungpo-dong 4ga, Youngdeungpo-gu, Seoul, 150-034, South Korea
| | - Chul Gu Kim
- Department of Ophthalmology, Kim's Eye Hospital, Konyang University College of Medicine, #156 Youngdeungpo-dong 4ga, Youngdeungpo-gu, Seoul, 150-034, South Korea
| | - Jong Woo Kim
- Department of Ophthalmology, Kim's Eye Hospital, Konyang University College of Medicine, #156 Youngdeungpo-dong 4ga, Youngdeungpo-gu, Seoul, 150-034, South Korea
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2016 Glenn A. Fry Award Lecture: Mechanisms and Potential Treatments of Early Age-Related Macular Degeneration. Optom Vis Sci 2017; 94:939-945. [DOI: 10.1097/opx.0000000000001124] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
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The Role of the P2X7 Receptor in Ocular Stresses: A Potential Therapeutic Target. Vision (Basel) 2017; 1:vision1020014. [PMID: 31740640 PMCID: PMC6835678 DOI: 10.3390/vision1020014] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Revised: 04/10/2017] [Accepted: 05/14/2017] [Indexed: 01/30/2023] Open
Abstract
The P2X7 receptor is expressed in both anterior and posterior segments of the eyeball. In the ocular surface, the P2X7 receptor is activated in case of external aggressions: preservatives and surfactants induce the activation of P2X7 receptors, leading to either apoptosis, inflammation, or cell proliferation. In the retina, the key endogenous actors of age-related macular degeneration, diabetic retinopathy, and glaucoma act through P2X7 receptors’ activation and/or upregulation of P2X7 receptors’ expression. Different therapeutic strategies aimed at the P2X7 receptor exist. P2X7 receptor antagonists, such as divalent cations and Brilliant Blue G (BBG) could be used to target either the ocular surface or the retina, as long as polyunsaturated fatty acids may exert their effects through the disruption of plasma membrane lipid rafts or saffron that reduces the response evoked by P2X7 receptor stimulation. Treatments against P2X7 receptor activation are proposed by using either eye drops or food supplements.
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Targeting the P2X7 Receptor in Age-Related Macular Degeneration. Vision (Basel) 2017; 1:vision1020011. [PMID: 31740637 PMCID: PMC6836166 DOI: 10.3390/vision1020011] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2016] [Revised: 03/30/2017] [Accepted: 03/30/2017] [Indexed: 01/07/2023] Open
Abstract
The P2X7 receptor (P2X7R) is a membrane receptor for the extracellular adenosine triphosphate (ATP). It functions as a ligand-gated non-selective cation channel and can mediate formation of a large non-selective membrane pore. Activation of the P2X7R induces multiple downstream events, including oxidative stress, inflammatory responses and cell death. Although the P2X7R has been identified in the retinal pigment epithelium (RPE) and different layers of retina, its biological and pathological functions as well as its downstream signaling pathways in the RPE and retina are not yet fully understood. Better understanding of the function of P2X7R in the RPE and retina under normal and disease states might lead to novel therapeutic targets in retinal diseases, including age-related macular degeneration (AMD). This brief review will mainly focus on recent findings on in vitro and in vivo evidence for the role of the P2X7R in the RPE and AMD.
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Hollborn M, Fischer S, Kuhrt H, Wiedemann P, Bringmann A, Kohen L. Osmotic regulation of NFAT5 expression in RPE cells: The involvement of purinergic receptor signaling. Mol Vis 2017; 23:116-130. [PMID: 28356704 PMCID: PMC5360457] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Accepted: 03/16/2017] [Indexed: 11/22/2022] Open
Abstract
PURPOSE Systemic hypertension is a risk factor for age-related neovascular retinal diseases. The major condition that induces hypertension is the intake of dietary salt (NaCl) resulting in increased extracellular osmolarity. High extracellular NaCl was has been shown to induce angiogenic factor production in RPE cells, in part via the transcriptional activity of nuclear factor of activated T cell 5 (NFAT5). Here, we determined the signaling pathways that mediate the osmotic expression of the NFAT5 gene in RPE cells. METHODS Cultured human RPE cells were stimulated with high (+100 mM) NaCl. Alterations in gene and protein expression were determined with real-time reverse transcriptase (RT)-PCR and western blot analysis, respectively. RESULTS NaCl-induced NFAT5 gene expression was fully inhibited by calcium chelation and blockers of inositol triphosphate (IP3) receptors and phospholipases C and A2. Blockers of phospholipases C and A2 also prevented the NaCl-induced increase of the cellular NFAT5 protein level. Inhibitors of multiple intracellular signaling transduction pathways and kinases, including p38 mitogen-activated protein kinase (MAPK), extracellular signal-regulated kinases 1 and 2 (ERK1/2), c-Jun NH2-terminal kinase (JNK), phosphatidylinositol-3 kinase (PI3K), protein kinases A and C, Src tyrosine kinases, and calpains, as well as cyclooxygenase inhibitors, decreased the NaCl-induced expression of the NFAT5 gene. In addition, autocrine purinergic signaling mediated by a release of ATP and a nucleoside transporter-mediated release of adenosine, activation of P2X7, P2Y1, P2Y2, and adenosine A1 receptors, but not adenosine A2A receptors, is required for the full expression of the NFAT5 gene under hyperosmotic conditions. NaCl-induced NFAT5 gene expression is in part dependent on the activity of nuclear factor κB (NF-κB). The NaCl-induced expression of NFAT5 protein was prevented by inhibitors of phospholipases C and A2 and an inhibitor of NF-κB, but it was not prevented by a P2Y1 inhibitor. CONCLUSIONS The data suggest that in addition to calcium signaling and activation of inflammatory enzymes, autocrine/paracrine purinergic signaling contributes to the stimulatory effect of hyperosmotic stress on the expression of the NFAT5 gene in RPE cells. It is suggested that high intake of dietary salt induces RPE cell responses, which may contribute to age-related retinal diseases.
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Affiliation(s)
- Margrit Hollborn
- Department of Ophthalmology and Eye Hospital, University of Leipzig, Leipzig, Germany
| | - Sarah Fischer
- Department of Ophthalmology and Eye Hospital, University of Leipzig, Leipzig, Germany
| | - Heidrun Kuhrt
- Paul Flechsig Institute of Brain Research, University of Leipzig Medical Faculty, Leipzig, Germany
| | - Peter Wiedemann
- Department of Ophthalmology and Eye Hospital, University of Leipzig, Leipzig, Germany
| | - Andreas Bringmann
- Department of Ophthalmology and Eye Hospital, University of Leipzig, Leipzig, Germany
| | - Leon Kohen
- Department of Ophthalmology and Eye Hospital, University of Leipzig, Leipzig, Germany,Helios Klinikum Aue, Aue, Germany
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Golestaneh N, Chu Y, Xiao YY, Stoleru GL, Theos AC. Dysfunctional autophagy in RPE, a contributing factor in age-related macular degeneration. Cell Death Dis 2017; 8:e2537. [PMID: 28055007 PMCID: PMC5386365 DOI: 10.1038/cddis.2016.453] [Citation(s) in RCA: 231] [Impact Index Per Article: 33.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Revised: 12/05/2016] [Accepted: 12/07/2016] [Indexed: 12/17/2022]
Abstract
Age-related macular degeneration (AMD) is a devastating neurodegenerative disease and a major cause of blindness in the developed world. Owing to its complexity and the lack of an adequate human model that recapitulates key aspects of the disease, the molecular mechanisms of AMD pathogenesis remain poorly understood. Here we show that cultured human retinal pigment epithelium (RPE) from AMD donors (AMD RPE) are functionally impaired and exhibit distinct phenotypes compared with RPE cultured from normal donors (normal RPE). Accumulation of lipid droplets and glycogen granules, disintegration of mitochondria, and an increase in autophagosomes were observed in AMD RPE cultures. Compared with normal RPE, AMD RPE exhibit increased susceptibility to oxidative stress, produce higher levels of reactive oxygen species (ROS) under stress conditions, and showed reduced mitochondrial activity. Measurement of the ratio of LC3-II/ LC3-I, revealed impaired autophagy in AMD RPE as compared with normal RPE. Autophagic flux was also reduced in AMD RPE as compared with normal RPE, as shown by inability of AMD RPE to downregulate p62 levels during starvation. Impaired autophagic pathways were further shown by analyzing late autophagic vesicles; immunostaining with lysosome-associated membrane protein 1 (LAMP-1) antibody revealed enlarged and annular LAMP-1-positive organelles in AMD RPE as opposed to smaller discrete puncta observed in normal RPE. Our study provides insights into AMD cellular and molecular mechanisms, proposes dysfunctional autophagy as an underlying mechanism contributing to the pathophysiology of the disease, and opens up new avenues for development of novel treatment strategies.
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Affiliation(s)
- Nady Golestaneh
- Department of Ophthalmology, Georgetown University Medical Center, Washington, DC, USA
- Department of Neurology, Georgetown University Medical Center, Washington, DC, USA
- Department of Biochemistry and Molecular & Cellular Biology, Georgetown University Medical Center, Washington, DC, USA
| | - Yi Chu
- Department of Ophthalmology, Georgetown University Medical Center, Washington, DC, USA
| | - Yang-Yu Xiao
- Department of Ophthalmology, Georgetown University Medical Center, Washington, DC, USA
| | - Gianna L Stoleru
- Department of Ophthalmology, Georgetown University Medical Center, Washington, DC, USA
| | - Alexander C Theos
- Department of Human Science, Georgetown University, Washington, DC, USA
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Bringmann A, Hollborn M, Kohen L, Wiedemann P. Intake of dietary salt and drinking water: Implications for the development of age-related macular degeneration. Mol Vis 2016; 22:1437-1454. [PMID: 28031693 PMCID: PMC5178186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Accepted: 12/20/2016] [Indexed: 10/26/2022] Open
Abstract
PURPOSE Systemic hypertension is a risk factor of age-related retinal diseases such as diabetic retinopathy and age-related macular degeneration. High intake of dietary salt and low intake of water increase extracellular osmolality resulting in hypertension, in particular in salt-sensitive individuals. This review summarizes the present knowledge regarding the impact of salt and water intake on the regulation of blood pressure, retinal function, and the development of age-related retinal diseases. METHODS A literature search of the Medline database and a summary of recent studies that used human RPE cells. RESULTS The salt sensitivity of the blood pressure and plasma osmolality increase with age, and body water deficits are common in older individuals. High plasma osmolality has adverse effects in the retina. In RPE cells, high osmolality induces expression and secretion of angiogenic factors, such as vascular endothelial growth factor (VEGF), placental growth factor, and basic fibroblast growth factor, and expression of aquaporin-5, a water channel implicated in transepithelial water transport. The transcriptional activities of hypoxia-inducible factor-1 (HIF-1) and nuclear factor of activated T cell 5 (NFAT5) are critical for the production of VEGF in response to salt-induced osmotic stress. Salt-induced osmotic stress also induces priming of the NLRP3 inflammasome and activates inflammatory enzymes in RPE cells. CONCLUSIONS Raised plasma osmolality may aggravate age-related retinal diseases by stimulation of local inflammation and angiogenic factor production in the RPE. Alterations in salt and water consumption, and of minerals that stimulate renal salt excretion, may offer nutritional approaches to prevent age-related retinal disorders, in particular in salt-sensitive individuals and individuals who show signs of body dehydration.
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Affiliation(s)
- Andreas Bringmann
- Department of Ophthalmology and Eye Hospital, University of Leipzig, Leipzig, Germany
| | - Margrit Hollborn
- Department of Ophthalmology and Eye Hospital, University of Leipzig, Leipzig, Germany
| | - Leon Kohen
- Department of Ophthalmology and Eye Hospital, University of Leipzig, Leipzig, Germany,Helios Klinikum Aue, Aue, Germany
| | - Peter Wiedemann
- Department of Ophthalmology and Eye Hospital, University of Leipzig, Leipzig, Germany
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Carver KA, Lin CM, Bowes Rickman C, Yang D. Lack of the P2X 7 receptor protects against AMD-like defects and microparticle accumulation in a chronic oxidative stress-induced mouse model of AMD. Biochem Biophys Res Commun 2016; 482:81-86. [PMID: 27810364 DOI: 10.1016/j.bbrc.2016.10.140] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Accepted: 10/29/2016] [Indexed: 12/17/2022]
Abstract
The P2X7 receptor (P2X7R) is an ATP-gated ion channel that is a key player in oxidative stress under pathological conditions. The P2X7R is expressed in the retinal pigmented epithelium (RPE) and neural retina. Chronic oxidative stress contributes to the pathogenesis of age-related macular degeneration (AMD). Mice lacking Cu, Zn superoxide dismutase (Sod1) developed chronic oxidative stress as well as AMD-like features, but whether the P2X7R plays a causative role in oxidative stress-induced AMD is unknown. Thus, the main purpose of this study was to test if concurrent knockout (KO) of P2X7R could block AMD-like defects seen in Sod1 KO mice. Using multiple approaches, we demonstrate that Sod1 KO causes AMD-like defects, including positive staining for oxidative stress markers, 3-nitrotyrosine and carboxymethyl lysine, thinning of the RPE and retina, thickening of Bruch's membrane, presence of basal laminar and linear deposits, RPE barrier disruption and accumulation of microglia/macrophages. Moreover, we find that Sod1 KO mice accumulate more microparticles (MPs) within RPE/choroid tissues. Concurrent KO of the P2X7R protects against AMD-like defects and MP accumulation in Sod1 KO mice. Together, we show for the first time, that deficiency of P2X7R prevents in vivo oxidative stress-induced accumulation of MPs and AMD-like defects. This work could potentially lead to novel therapies for AMD and other oxidative stress-driven diseases.
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Affiliation(s)
- Kyle A Carver
- Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, MI 48105, USA
| | - C M Lin
- Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, MI 48105, USA
| | - Catherine Bowes Rickman
- Department of Ophthalmology, Duke Eye Center, Duke University, Durham, NC 27710, USA; Department of Cell Biology, Duke University, Durham, NC 27710, USA
| | - Dongli Yang
- Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, MI 48105, USA.
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Ho T, Aplin FP, Jobling AI, Phipps JA, de Iongh RU, Greferath U, Vessey KA, Fletcher EL. Localization and Possible Function of P2X Receptors in Normal and Diseased Retinae. J Ocul Pharmacol Ther 2016; 32:509-517. [DOI: 10.1089/jop.2015.0158] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Affiliation(s)
- Tracy Ho
- Department of Anatomy and Neuroscience, The University of Melbourne, Parkville, Australia
| | - Felix P. Aplin
- Department of Anatomy and Neuroscience, The University of Melbourne, Parkville, Australia
| | - Andrew I. Jobling
- Department of Anatomy and Neuroscience, The University of Melbourne, Parkville, Australia
| | - Joanna A. Phipps
- Department of Anatomy and Neuroscience, The University of Melbourne, Parkville, Australia
| | - Robb U. de Iongh
- Department of Anatomy and Neuroscience, The University of Melbourne, Parkville, Australia
| | - Ursula Greferath
- Department of Anatomy and Neuroscience, The University of Melbourne, Parkville, Australia
| | - Kirstan A. Vessey
- Department of Anatomy and Neuroscience, The University of Melbourne, Parkville, Australia
| | - Erica L. Fletcher
- Department of Anatomy and Neuroscience, The University of Melbourne, Parkville, Australia
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How Azobenzene Photoswitches Restore Visual Responses to the Blind Retina. Neuron 2016; 92:100-113. [PMID: 27667006 DOI: 10.1016/j.neuron.2016.08.038] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2015] [Revised: 07/02/2016] [Accepted: 08/25/2016] [Indexed: 01/13/2023]
Abstract
Azobenzene photoswitches confer light sensitivity onto retinal ganglion cells (RGCs) in blind mice, making these compounds promising candidates as vision-restoring drugs in humans with degenerative blindness. Remarkably, photosensitization manifests only in animals with photoreceptor degeneration and is absent from those with intact rods and cones. Here we show that P2X receptors mediate the entry of photoswitches into RGCs, where they associate with voltage-gated ion channels, enabling light to control action-potential firing. All charged photoswitch compounds require permeation through P2X receptors, whose gene expression is upregulated in the blind retina. Photoswitches and membrane-impermeant fluorescent dyes likewise penetrate through P2X receptors to label a subset of RGCs in the degenerated retina. Electrophysiological recordings and mapping of fluorescently labeled RGC dendritic projections together indicate that photosensitization is highly selective for OFF-RGCs. Hence, P2X receptors are a natural conduit allowing cell-type-selective and degeneration-specific delivery of photoswitches to restore visual function in blinding disease.
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43
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Deregulation of ocular nucleotide homeostasis in patients with diabetic retinopathy. J Mol Med (Berl) 2016; 95:193-204. [PMID: 27638339 DOI: 10.1007/s00109-016-1472-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2016] [Revised: 08/31/2016] [Accepted: 09/07/2016] [Indexed: 10/21/2022]
Abstract
Clear signaling roles for ATP and adenosine have been established in all tissues, including the eye. The magnitude of signaling responses is governed by networks of enzymes; however, little is known about the regulatory mechanisms of purinergic signaling in the eye. By employing thin-layer chromatographic assays with 3H-labeled substrates, this study aimed to evaluate the role of nucleotide homeostasis in the pathogenesis of vitreoretinal diseases in humans. We have identified soluble enzymes ecto-5'-nucleotidase/CD73, adenylate kinase-1, and nucleoside diphosphate kinase in the vitreous fluid that control active cycling between pro-inflammatory ATP and anti-inflammatory adenosine. Strikingly, patients with proliferative form of diabetic retinopathy (DR) had higher adenylate kinase activity and ATP concentration, when compared to non-proliferative DR eyes and non-diabetic controls operated for rhegmatogenous retinal detachment, macular hole, and pucker. The non-parametric correlation analysis revealed positive correlations between intravitreal adenylate kinase and concentrations of ATP, ADP, and other angiogenic (angiopoietins-1 and -2), profibrotic (transforming growth factor-β1), and proteolytic (matrix metalloproteinase-9) factors but not erythropoietin and VEGF. Immunohistochemical staining of postmortem human retina additionally revealed selective expression of ecto-5'-nucleotidase/CD73 on the rod-and-cone-containing photoreceptor cells. Collectively, these findings provide novel insights into the regulatory mechanisms that influence purinergic signaling in diseased eye and open up new possibilities in the development of enzyme-targeted therapeutic approaches for prevention and treatment of DR. KEY MESSAGE Ecto-5'-nucleotidase/CD73 and adenylate kinase-1 circulate in human vitreous fluid. Adenylate kinase activity is high in diabetic eyes with proliferative retinopathy. Diabetic eyes display higher intravitreal ATP/ADP ratio than non-diabetic controls. Soluble adenylate kinase maintains resynthesis of inflammatory ATP in diabetic eyes.
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P2X7-pannexin-1 and amyloid β-induced oxysterol input in human retinal cell: Role in age-related macular degeneration? Biochimie 2016; 127:70-8. [PMID: 27109381 DOI: 10.1016/j.biochi.2016.04.014] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Accepted: 04/15/2016] [Indexed: 02/07/2023]
Abstract
Age-related macular degeneration (AMD) is the most common cause of severe vision loss worldwide. Amyloid β involvement in degenerative diseases such as AMD is well known and its toxicity has been related to P2X7 receptor-pannexin-1. Recently, oxysterols (oxidized derivatives of cholesterol) have been implicated in AMD pathogenesis. The aim of our study was to highlight amyloid β/oxysterols relationship and to describe P2X7 receptor-pannexin-1 role in oxysterols toxicity. Using retinal epithelial cells, we first quantified sterols levels after amyloid β incubation and second we investigated the cytotoxic effects induced by oxysterols. For the first time, our results showed that amyloid β induced oxysterols formation in human retinal pigmented epithelial cells. We showed that oxysterol toxicity is mediated by P2X7 receptor activation. This activation was dependent on pannexin-1 with 25-hydroxycholesterol whereas P2X7 receptor signaling pathway was pannexin-1-independent for 7-ketocholesterol. Taken together our data suggest a pivotal role of P2X7 receptor-pannexin-1 in oxysterols toxicity in retinal cells which could be an important target to develop new treatments for AMD.
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Corso L, Cavallero A, Baroni D, Garbati P, Prestipino G, Bisti S, Nobile M, Picco C. Saffron reduces ATP-induced retinal cytotoxicity by targeting P2X7 receptors. Purinergic Signal 2016; 12:161-74. [PMID: 26739703 DOI: 10.1007/s11302-015-9490-3] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Accepted: 12/15/2015] [Indexed: 11/25/2022] Open
Abstract
P2X7-type purinergic receptors are distributed throughout the nervous system where they contribute to physiological and pathological functions. In the retina, this receptor is found in both inner and outer cells including microglia modulating signaling and health of retinal cells. It is involved in retinal neurodegenerative disorders such as retinitis pigmentosa and age-related macular degeneration (AMD). Experimental studies demonstrated that saffron protects photoreceptors from light-induced damage preserving both retinal morphology and visual function and improves retinal flicker sensitivity in AMD patients. To evaluate a possible interaction between saffron and P2X7 receptors (P2X7Rs), different cellular models and experimental approaches were used. We found that saffron positively influences the viability of mouse primary retinal cells and photoreceptor-derived 661W cells exposed to ATP, and reduced the ATP-induced intracellular calcium increase in 661W cells. Similar results were obtained on HEK cells transfected with recombinant rat P2X7R but not on cells transfected with rat P2X2R. Finally, patch-clamp experiments showed that saffron inhibited cationic currents in HEK-P2X7R cells. These results point out a novel mechanism through which saffron may exert its protective role in neurodegeneration and support the idea that P2X7-mediated calcium signaling may be a crucial therapeutic target in the treatment of neurodegenerative diseases.
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Affiliation(s)
- Lucia Corso
- National Research Council, Institute of Biophysics, Via De Marini 6, 16149, Genoa, Italy.,Department of Biotechnology and Applied clinical Science, DISCAB, University of L'Aquila, L'Aquila, Italy
| | - Anna Cavallero
- National Research Council, Institute of Biophysics, Via De Marini 6, 16149, Genoa, Italy
| | - Debora Baroni
- National Research Council, Institute of Biophysics, Via De Marini 6, 16149, Genoa, Italy
| | - Patrizia Garbati
- National Research Council, Institute of Biophysics, Via De Marini 6, 16149, Genoa, Italy
| | - Gianfranco Prestipino
- National Research Council, Institute of Biophysics, Via De Marini 6, 16149, Genoa, Italy
| | - Silvia Bisti
- Department of Biotechnology and Applied clinical Science, DISCAB, University of L'Aquila, L'Aquila, Italy
| | - Mario Nobile
- National Research Council, Institute of Biophysics, Via De Marini 6, 16149, Genoa, Italy
| | - Cristiana Picco
- National Research Council, Institute of Biophysics, Via De Marini 6, 16149, Genoa, Italy.
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Wakx A, Dutot M, Massicot F, Mascarelli F, Limb GA, Rat P. Amyloid β Peptide Induces Apoptosis Through P2X7 Cell Death Receptor in Retinal Cells: Modulation by Marine Omega-3 Fatty Acid DHA and EPA. Appl Biochem Biotechnol 2016; 178:368-81. [PMID: 26467741 PMCID: PMC4718936 DOI: 10.1007/s12010-015-1878-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2015] [Accepted: 09/28/2015] [Indexed: 11/25/2022]
Abstract
Retinal Müller glial cells have already been implicated in age-related macular degeneration (AMD). AMD is characterized by accumulation of toxic amyloid-β peptide (Aβ); the question we raise is as follows: is P2X7 receptor, known to play an important role in several degenerative diseases, involved in Aβ toxicity on Müller cells? Retinal Müller glial cells were incubated with Aβ for 48 h. Cell viability was assessed using the alamarBlue assay and cytotoxicity using the lactate dehydrogenase (LDH) release assay. P2X7 receptor expression was highlighted by immunolabeling observed on confocal microscopy and its activation was evaluated by YO-PRO-1 assay. Hoechst 33342 was used to evaluate chromatin condensation, and caspases 8 and 3 activation was assessed using AMC assays. Lipid formulation rich in eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) used in Age-Related Eye Disease Study 2 was incubated on cells for 15 min prior to Aβ incubation. For the first time, we showed that Aβ induced caspase-independent apoptosis through P2X7 receptor activation on our retinal model. DHA and EPA are polyunsaturated fatty acids recommended in food supplement to prevent AMD. We therefore modulated Aβ cytotoxicity using a lipid formulation rich in DHA and EPA to have a better understanding of the results observed in clinical studies. We showed that fish oil rich in EPA and DHA, in combination with a potent P2X7 receptor antagonist, represents an efficient modulator of Aβ toxicity and that P2X7 could be an interesting therapeutic target to prevent AMD.
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Affiliation(s)
- Anaïs Wakx
- />UMR CNRS 8638—Chimie-Toxicologie Analytique et Cellulaire, Sorbonne Paris Cité, Faculté de Pharmacie, Université Paris Descartes, 4 avenue de l’Observatoire, 75006 Paris, France
- />Inserm U598, Physiopathologie des maladies oculaires, Innovations thérapeutiques, Centre de Recherches Biomédicales des Cordeliers, 75270 Paris Cedex 06, France
| | - Mélody Dutot
- />UMR CNRS 8638—Chimie-Toxicologie Analytique et Cellulaire, Sorbonne Paris Cité, Faculté de Pharmacie, Université Paris Descartes, 4 avenue de l’Observatoire, 75006 Paris, France
- />Laboratoire Yslab, 2 rue Félix Le Dantec, 29000 Quimper, France
- />Inserm U598, Physiopathologie des maladies oculaires, Innovations thérapeutiques, Centre de Recherches Biomédicales des Cordeliers, 75270 Paris Cedex 06, France
| | - France Massicot
- />UMR CNRS 8638—Chimie-Toxicologie Analytique et Cellulaire, Sorbonne Paris Cité, Faculté de Pharmacie, Université Paris Descartes, 4 avenue de l’Observatoire, 75006 Paris, France
- />Inserm U598, Physiopathologie des maladies oculaires, Innovations thérapeutiques, Centre de Recherches Biomédicales des Cordeliers, 75270 Paris Cedex 06, France
| | - Frédéric Mascarelli
- />INSERM U 872—Physiopathologie des maladies oculaires: Innovations thérapeutiques, Centre de Recherches des Cordeliers, 15 Rue de l’Ecole de Médecine, 75006 Paris, France
- />Inserm U598, Physiopathologie des maladies oculaires, Innovations thérapeutiques, Centre de Recherches Biomédicales des Cordeliers, 75270 Paris Cedex 06, France
| | - G. Astrid Limb
- />Division of Ocular Biology and Therapeutics, UCL Institute of Ophthalmology and Moorfields Eye Hospital, 11 Bath Street, London, EC1V 9EL UK
| | - Patrice Rat
- />UMR CNRS 8638—Chimie-Toxicologie Analytique et Cellulaire, Sorbonne Paris Cité, Faculté de Pharmacie, Université Paris Descartes, 4 avenue de l’Observatoire, 75006 Paris, France
- />Inserm U598, Physiopathologie des maladies oculaires, Innovations thérapeutiques, Centre de Recherches Biomédicales des Cordeliers, 75270 Paris Cedex 06, France
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47
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Muraoka Y, Tsujikawa A, Takahashi A, Iida Y, Murakami T, Ooto S, Suzuma K, Uji A, Yoshimura N. Foveal Damage Due to Subfoveal Hemorrhage Associated with Branch Retinal Vein Occlusion. PLoS One 2015; 10:e0144894. [PMID: 26661582 PMCID: PMC4677927 DOI: 10.1371/journal.pone.0144894] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2015] [Accepted: 11/24/2015] [Indexed: 11/18/2022] Open
Abstract
To investigate the functional and morphologic prognoses of eyes with subfoveal hemorrhage from acute branch retinal vein occlusion (BRVO), and to examine the effect of intravitreal ranibizumab injection (IVR) on these prognoses, we assessed 81 eyes with acute BRVO, of which 38 did not receive IVR [IVR(-) group], and 43 were treated with IVR [IVR(+) group] for macular edema. The foveal morphologic changes were examined via optical coherence tomography (OCT). At initial examination, 63 eyes exhibited subfoveal hemorrhage. At final examination, the defect lengths in the foveal external limiting membrane (ELM) and ellipsoid lines in these eyes were longer, and final VA was significantly poorer, compared with eyes without subfoveal hemorrhage. In comparisons between the final measurements in eyes with subfoveal hemorrhage in the IVR(-) and IVR(+) groups, while there were no differences in initial ocular conditions, final VA was significantly better in the IVR(+) group. The defects in the ELM and ellipsoid lines in the IVR(+) group were shorter than those of the IVR(-) group (p = 0.002 in both). Final VA was correlated with the defect lengths of foveal ELM and ellipsoid lines in both the IVR(-) and IVR(+) groups (both p < 0.001). In addition, the defect lengths of foveal ELM and ellipsoid lines were closely correlated with the duration of subfoveal hemorrhage (both p < 0.001). BRVO-associated subfoveal hemorrhage caused damage to the foveal photoreceptors, and visual dysfunction. However, IVR improved these prognoses, by accelerating the absorption of the subfoveal hemorrhage.
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Affiliation(s)
- Yuki Muraoka
- Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto, Japan
- * E-mail:
| | - Akitaka Tsujikawa
- Department of Ophthalmology, Kagawa University Faculty of Medicine, Kagawa, Japan
| | - Ayako Takahashi
- Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Yuto Iida
- Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Tomoaki Murakami
- Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Sotaro Ooto
- Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Kiyoshi Suzuma
- Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Akihito Uji
- Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Nagahisa Yoshimura
- Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto, Japan
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48
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Nakahira K, Hisata S, Choi AMK. The Roles of Mitochondrial Damage-Associated Molecular Patterns in Diseases. Antioxid Redox Signal 2015; 23:1329-50. [PMID: 26067258 PMCID: PMC4685486 DOI: 10.1089/ars.2015.6407] [Citation(s) in RCA: 199] [Impact Index Per Article: 22.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
SIGNIFICANCE Mitochondria, vital cellular power plants to generate energy, are involved in immune responses. Mitochondrial damage-associated molecular patterns (DAMPs) are molecules that are released from mitochondria to extracellular space during cell death and include not only proteins but also DNA or lipids. Mitochondrial DAMPs induce inflammatory responses and are critically involved in the pathogenesis of various diseases. RECENT ADVANCES Recent studies elucidate the molecular mechanisms by which mitochondrial DAMPs are released and initiate immune responses by use of genetically modulated cells or animals. Importantly, the levels of mitochondrial DAMPs in patients are often associated with severity and prognosis of human diseases, such as infection, asthma, ischemic heart disease, and cancer. CRITICAL ISSUES Although mitochondrial DAMPs can represent proinflammatory molecules in various experimental models, their roles in human diseases may be multifunctional and complex. It remains unclear where and how mitochondrial DAMPs are liberated into extracellular spaces and exert their biological functions particularly in vivo. In addition, while mitochondria can secrete several types of DAMPs during cell death, the interaction of each mitochondrial DAMP (e.g., synergistic effects) remains unclear. FUTURE DIRECTIONS Regulation of mitochondrial DAMP-mediated immune responses may be important to alter the progression of human diseases. In addition, measuring mitochondrial DAMPs in patients may be clinically useful as biomarkers to predict prognosis or response to therapies. Further studies of the mechanisms by which mitochondrial DAMPs impact the initiation and progression of diseases may lead to the development of therapeutics specifically targeting this pathway. Antioxid.
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Affiliation(s)
- Kiichi Nakahira
- 1 Joan and Sanford I. Weill Department of Medicine, Weill Cornell Medical College and New York-Presbyterian Hospital , New York, New York.,2 Division of Pulmonary and Critical Care Medicine, Weill Cornell Medical College , New York, New York
| | - Shu Hisata
- 1 Joan and Sanford I. Weill Department of Medicine, Weill Cornell Medical College and New York-Presbyterian Hospital , New York, New York.,2 Division of Pulmonary and Critical Care Medicine, Weill Cornell Medical College , New York, New York
| | - Augustine M K Choi
- 1 Joan and Sanford I. Weill Department of Medicine, Weill Cornell Medical College and New York-Presbyterian Hospital , New York, New York.,2 Division of Pulmonary and Critical Care Medicine, Weill Cornell Medical College , New York, New York
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49
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Hashimoto Y, Saito W, Fujiya A, Yoshizawa C, Hirooka K, Mori S, Noda K, Ishida S. Changes in Inner and Outer Retinal Layer Thicknesses after Vitrectomy for Idiopathic Macular Hole: Implications for Visual Prognosis. PLoS One 2015; 10:e0135925. [PMID: 26291526 PMCID: PMC4546191 DOI: 10.1371/journal.pone.0135925] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Accepted: 07/28/2015] [Indexed: 11/22/2022] Open
Abstract
Purpose To investigate sequential post-operative thickness changes in inner and outer retinal layers in eyes with an idiopathic macular hole (MH). Methods Retrospective case series. Twenty-four eyes of 23 patients who had received pars plana vitrectomy (PPV) for the closure of MH were included in the study. Spectral domain optical coherence tomography C-scan was used to automatically measure the mean thickness of the inner and outer retinal layers pre-operatively and up to 6 months following surgery. The photoreceptor outer segment (PROS) length was measured manually and was used to assess its relationship with best-corrected visual acuity (BCVA). Results Compared with the pre-operative thickness, the inner layers significantly thinned during follow-up (P = 0.02), particularly in the parafoveal (P = 0.01), but not perifoveal, area. The post-operative inner layer thinning ranged from the ganglion cell layer to the inner plexiform layer (P = 0.002), whereas the nerve fiber layer was unaltered. Outer layer thickness was significantly greater post-operatively (P = 0.002), and especially the PROS lengthened not only in the fovea but also in the parafovea (P < 0.001). Six months after surgery, BCVA was significantly correlated exclusively with the elongated foveal PROS (R = 0.42, P = 0.03), but not with any of the other thickness parameters examined. Conclusions Following PPV for MH, retinal inner layers other than the nerve fiber layer thinned, suggestive of subclinical thickening in the inner layers where no cyst was evident pre-operatively. In contrast, retinal outer layer thickness significantly increased, potentially as a result of PROS elongation linking tightly with favorable visual prognosis in MH eyes.
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Affiliation(s)
- Yuki Hashimoto
- Department of Ophthalmology, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - Wataru Saito
- Department of Ophthalmology, Hokkaido University Graduate School of Medicine, Sapporo, Japan
- Department of Ocular Circulation and Metabolism, Hokkaido University Graduate School of Medicine, Sapporo, Japan
- * E-mail:
| | - Akio Fujiya
- Department of Ophthalmology, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - Chikako Yoshizawa
- Department of Ophthalmology, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - Kiriko Hirooka
- Department of Ophthalmology, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - Shohei Mori
- Department of Ophthalmology, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - Kousuke Noda
- Department of Ophthalmology, Hokkaido University Graduate School of Medicine, Sapporo, Japan
- Department of Ocular Circulation and Metabolism, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - Susumu Ishida
- Department of Ophthalmology, Hokkaido University Graduate School of Medicine, Sapporo, Japan
- Department of Ocular Circulation and Metabolism, Hokkaido University Graduate School of Medicine, Sapporo, Japan
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50
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Upregulation of P2RX7 in Cx3cr1-Deficient Mononuclear Phagocytes Leads to Increased Interleukin-1β Secretion and Photoreceptor Neurodegeneration. J Neurosci 2015; 35:6987-96. [PMID: 25948251 DOI: 10.1523/jneurosci.3955-14.2015] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Photoreceptor degeneration in age-related macular degeneration (AMD) is associated with an infiltration and chronic accumulation of mononuclear phagocytes (MPs). We have previously shown that Cx3cr1-deficient mice develop age- and stress- related subretinal accumulation of MPs, which is associated with photoreceptor degeneration. Cx3cr1-deficient MPs have been shown to increase neuronal apoptosis through IL-1β in neuroinflammation of the brain. The reason for increased IL-1β secretion from Cx3cr1-deficient MPs, and whether IL-1β is responsible for increased photoreceptor apoptosis in Cx3cr1-deficient mice, has not been elucidated. Here we show that Cx3cr1-deficient MPs express increased surface P2X7 receptor (P2RX7), which stimulates IL-1β maturation and secretion. P2RX7 and IL-1β inhibition efficiently blunted Cx3cr1-MP-dependent photoreceptor apoptosis in a monocyte/retina coculture system and in light-induced subretinal inflammation of Cx3cr1-deficient mice in vivo. Our results provide an explanation for increased CX3CR1-dependent IL-1β secretion and suggest that IL-1β or P2RX7 inhibition can help inhibit the inflammation-associated photoreceptor cell loss in late AMD, including geographic atrophy, for which no efficient treatment currently exists.
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