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Zhou S, Taskintuna K, Hum J, Gulati J, Olaya S, Steinman J, Golestaneh N. PGC-1α repression dysregulates lipid metabolism and induces lipid droplet accumulation in retinal pigment epithelium. Cell Death Dis 2024; 15:385. [PMID: 38824126 PMCID: PMC11144268 DOI: 10.1038/s41419-024-06762-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 05/16/2024] [Accepted: 05/20/2024] [Indexed: 06/03/2024]
Abstract
Drusen, the yellow deposits under the retina, are composed of lipids and proteins, and represent a hallmark of age-related macular degeneration (AMD). Lipid droplets are also reported in the retinal pigment epithelium (RPE) from AMD donor eyes. However, the mechanisms underlying these disease phenotypes remain elusive. Previously, we showed that Pgc-1α repression, combined with a high-fat diet (HFD), induce drastic AMD-like phenotypes in mice. We also reported increased PGC-1α acetylation and subsequent deactivation in the RPE derived from AMD donor eyes. Here, through a series of in vivo and in vitro experiments, we sought to investigate the molecular mechanisms by which PGC-1α repression could influence RPE and retinal function. We show that PGC-1α plays an important role in RPE and retinal lipid metabolism and function. In mice, repression of Pgc-1α alone induced RPE and retinal degeneration and drusen-like deposits. In vitro inhibition of PGC1A by CRISPR-Cas9 gene editing in human RPE (ARPE19- PGC1A KO) affected the expression of genes responsible for lipid metabolism, fatty acid β-oxidation (FAO), fatty acid transport, low-density lipoprotein (LDL) uptake, cholesterol esterification, cholesterol biosynthesis, and cholesterol efflux. Moreover, inhibition of PGC1A in RPE cells caused lipid droplet accumulation and lipid peroxidation. ARPE19-PGC1A KO cells also showed reduced mitochondrial biosynthesis, impaired mitochondrial dynamics and activity, reduced antioxidant enzymes, decreased mitochondrial membrane potential, loss of cardiolipin, and increased susceptibility to oxidative stress. Our data demonstrate the crucial role of PGC-1α in regulating lipid metabolism. They provide new insights into the mechanisms involved in lipid and drusen accumulation in the RPE and retina during aging and AMD, which may pave the way for developing novel therapeutic strategies targeting PGC-1α.
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Affiliation(s)
- Shuyan Zhou
- Department of Ophthalmology, Georgetown University Medical Center, Washington, DC, 20007, USA
| | - Kaan Taskintuna
- Department of Ophthalmology, Georgetown University Medical Center, Washington, DC, 20007, USA
| | - Jacob Hum
- Department of Ophthalmology, Georgetown University Medical Center, Washington, DC, 20007, USA
| | - Jasmine Gulati
- Department of Ophthalmology, Georgetown University Medical Center, Washington, DC, 20007, USA
| | - Stephanie Olaya
- Department of Ophthalmology, Georgetown University Medical Center, Washington, DC, 20007, USA
| | - Jeremy Steinman
- Department of Ophthalmology, Georgetown University Medical Center, Washington, DC, 20007, USA
| | - Nady Golestaneh
- Department of Ophthalmology, Georgetown University Medical Center, Washington, DC, 20007, USA.
- Department of Neurology, Georgetown University Medical Center, Washington, DC, 20007, USA.
- Department of Biochemistry and Molecular & Cellular Biology, Washington, DC, 20007, USA.
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Gurubaran IS, Watala C, Kostanek J, Szczepanska J, Pawlowska E, Kaarniranta K, Blasiak J. PGC-1α regulates the interplay between oxidative stress, senescence and autophagy in the ageing retina important in age-related macular degeneration. J Cell Mol Med 2024; 28:e18051. [PMID: 38571282 PMCID: PMC10992479 DOI: 10.1111/jcmm.18051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Revised: 09/25/2023] [Accepted: 11/09/2023] [Indexed: 04/05/2024] Open
Abstract
We previously showed that mice with knockout in the peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PPARGC1A) gene encoding the PGC-1α protein, and nuclear factor erythroid 2 like 2 (NFE2L2) gene, exhibited some features of the age-related macular degeneration (AMD) phenotype. To further explore the mechanism behind the involvement of PGC-1α in AMD pathogenesis we used young (3-month) and old (12-month) mice with knockout in the PPARGC1A gene and age-matched wild-type (WT) animals. An immunohistochemical analysis showed age-dependent different expression of markers of oxidative stress defence, senescence and autophagy in the retinal pigment epithelium of KO animals as compared with their WT counterparts. Multivariate inference testing showed that senescence and autophagy proteins had the greatest impact on the discrimination between KO and WT 3-month animals, but proteins of antioxidant defence also contributed to that discrimination. A bioinformatic analysis showed that PGC-1α might coordinate the interplay between genes encoding proteins involved in antioxidant defence, senescence and autophagy in the ageing retina. These data support importance of PGC-1α in AMD pathogenesis and confirm the utility of mice with PGC-1α knockout as an animal model to study AMD pathogenesis.
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Affiliation(s)
| | - Cezary Watala
- Department of Haemostatic DisordersMedical University of LodzLodzPoland
| | - Joanna Kostanek
- Department of Haemostatic DisordersMedical University of LodzLodzPoland
| | | | | | - Kai Kaarniranta
- Department of OphthalmologyUniversity of Eastern FinlandKuopioFinland
- Department of OphthalmologyKuopio University HospitalKuopioFinland
| | - Janusz Blasiak
- Faculty of Medicine, Collegium MedicumMazovian Academy in PlockPlock09‐402Poland
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Zhang H, Song T, Kang R, Ren F, Liu J, Wang J. Plant bioactive compounds alleviate photoinduced retinal damage and asthenopia: Mechanisms, synergies, and bioavailability. Nutr Res 2023; 120:115-134. [PMID: 37980835 DOI: 10.1016/j.nutres.2023.10.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Revised: 10/26/2023] [Accepted: 10/26/2023] [Indexed: 11/21/2023]
Abstract
The retina, an important tissue of the eye, is essential in visual transmission and sustaining adequate eyesight. However, oxidative stress and inflammatory reactions can harm retinal structure and function. Recent studies have demonstrated that exposure to light can induce oxidative stress and inflammatory reactions in retinal cells, thereby facilitating the progression of retinal damage-related diseases and asthenopia. Plant bioactive compounds such as anthocyanin, curcumin, resveratrol, lutein, zeaxanthin, epigallocatechin gallate, and quercetin are effective in alleviating retinal damage and asthenopia. Their strong oxidation resistance and unique chemical structure can prevent the retina from producing reactive oxygen species and regulating eye muscle relaxation, thus alleviating retinal damage and asthenopia. Additionally, the combination of these active ingredients produces a stronger antioxidant effect. Consequently, understanding the mechanism of retinal damage caused by light and the regulation mechanism of bioactive compounds can better protect the retina and reduce asthenopia.
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Affiliation(s)
- Huijuan Zhang
- China-Canada Joint Lab of Food Nutrition and Health (Beijing), Key Laboratory of Special Food Supervision Technology for State Market Regulation, School of Food and Health, Beijing Technology & Business University (BTBU), Beijing, 100048, China.
| | - Tiancong Song
- China-Canada Joint Lab of Food Nutrition and Health (Beijing), Key Laboratory of Special Food Supervision Technology for State Market Regulation, School of Food and Health, Beijing Technology & Business University (BTBU), Beijing, 100048, China
| | - Rui Kang
- China-Canada Joint Lab of Food Nutrition and Health (Beijing), Key Laboratory of Special Food Supervision Technology for State Market Regulation, School of Food and Health, Beijing Technology & Business University (BTBU), Beijing, 100048, China
| | - Feiyue Ren
- China-Canada Joint Lab of Food Nutrition and Health (Beijing), Key Laboratory of Special Food Supervision Technology for State Market Regulation, School of Food and Health, Beijing Technology & Business University (BTBU), Beijing, 100048, China
| | - Jie Liu
- China-Canada Joint Lab of Food Nutrition and Health (Beijing), Key Laboratory of Special Food Supervision Technology for State Market Regulation, School of Food and Health, Beijing Technology & Business University (BTBU), Beijing, 100048, China
| | - Jing Wang
- China-Canada Joint Lab of Food Nutrition and Health (Beijing), Key Laboratory of Special Food Supervision Technology for State Market Regulation, School of Food and Health, Beijing Technology & Business University (BTBU), Beijing, 100048, China.
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Soleimani M, Cheraqpour K, Koganti R, Djalilian AR. Cellular senescence and ophthalmic diseases: narrative review. Graefes Arch Clin Exp Ophthalmol 2023; 261:3067-3082. [PMID: 37079093 DOI: 10.1007/s00417-023-06070-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Revised: 03/21/2023] [Accepted: 04/11/2023] [Indexed: 04/21/2023] Open
Abstract
PURPOSE Cellular senescence is a state of permanent growth arrest whereby a cell reaches its replicative limit. However, senescence can also be triggered prematurely in certain stressors including radiation, oxidative stress, and chemotherapy. This stress-induced senescence has been studied in the context of promoting inflammation, tumor development, and several chronic degenerative diseases of aging. Emerging research has elucidated the role of senescence in various ocular diseases. METHODS The literature search was performed using PubMed with using the query (senescence OR aging) AND (eye disease OR ocular disease OR ophthalmic disease OR cornea OR glaucoma OR cataract OR retina) on October 20th, 2022. No time restriction was proposed. Articles were excluded if they were not referenced in English. RESULTS Overall, 51 articles regarding senescence and ocular diseases were found and summarized in this study. Several signaling pathways have been implicated in the development of senescence. Currently, senescence has been linked to various corneal and retinal pathologies, as well as cataract and glaucoma. Given the number of pathologies, senolytics, which are small molecules with the ability to selective targeting of senescent cells, can be used as therapeutic or prophylactic agents. CONCLUSIONS Senescence has been shown to underlie the pathogenesis of numerous ocular diseases. The overall literature on senescence and ocular disease is growing rapidly. There is an ongoing debate whether or not cellular senescence detected in experiments contributes in a significant way to diseases. Research on understanding the mechanism of senescence from ocular cells and tissues is just beginning. Multiple animal models are required to test potential senolytics. Currently, no studies exist to date which have demonstrated the benefits of senolytic therapies in human studies.
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Affiliation(s)
- Mohammad Soleimani
- Eye Research Center, Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran
- Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, Chicago, IL, USA
- Cornea Service, Stem Cell Therapy and Corneal Tissue Engineering Laboratory, Illinois Eye and Ear Infirmary, 1855 W. Taylor Street, M/C 648, Chicago, IL, 60612, USA
| | - Kasra Cheraqpour
- Eye Research Center, Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran
| | - Raghuram Koganti
- Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, Chicago, IL, USA
| | - Ali R Djalilian
- Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, Chicago, IL, USA.
- Cornea Service, Stem Cell Therapy and Corneal Tissue Engineering Laboratory, Illinois Eye and Ear Infirmary, 1855 W. Taylor Street, M/C 648, Chicago, IL, 60612, USA.
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Chhabra S, Mehan S. Matrine exerts its neuroprotective effects by modulating multiple neuronal pathways. Metab Brain Dis 2023; 38:1471-1499. [PMID: 37103719 DOI: 10.1007/s11011-023-01214-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Accepted: 04/10/2023] [Indexed: 04/28/2023]
Abstract
Recent evidence suggests that misfolding, clumping, and accumulation of proteins in the brain may be common causes and pathogenic mechanism for several neurological illnesses. This causes neuronal structural deterioration and disruption of neural circuits. Research from various fields supports this idea, indicating that developing a single treatment for several severe conditions might be possible. Phytochemicals from medicinal plants play an essential part in maintaining the brain's chemical equilibrium by affecting the proximity of neurons. Matrine is a tetracyclo-quinolizidine alkaloid derived from the plant Sophora flavescens Aiton. Matrine has been shown to have a therapeutic effect on Multiple Sclerosis, Alzheimer's disease, and various other neurological disorders. Numerous studies have demonstrated that matrine protects neurons by altering multiple signalling pathways and crossing the blood-brain barrier. As a result, matrine may have therapeutic utility in the treatment of a variety of neurocomplications. This work aims to serve as a foundation for future clinical research by reviewing the current state of matrine as a neuroprotective agent and its potential therapeutic application in treating neurodegenerative and neuropsychiatric illnesses. Future research will answer many concerns and lead to fascinating discoveries that could impact other aspects of matrine.
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Affiliation(s)
- Swesha Chhabra
- Division of Neuroscience, Department of Pharmacology, ISF College of Pharmacy, Moga, 142001, Punjab, India
| | - Sidharth Mehan
- Division of Neuroscience, Department of Pharmacology, ISF College of Pharmacy, Moga, 142001, Punjab, India.
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The Anti-Aging Hormone Klotho Promotes Retinal Pigment Epithelium Cell Viability and Metabolism by Activating the AMPK/PGC-1α Pathway. Antioxidants (Basel) 2023; 12:antiox12020385. [PMID: 36829944 PMCID: PMC9952846 DOI: 10.3390/antiox12020385] [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: 12/30/2022] [Revised: 01/30/2023] [Accepted: 01/30/2023] [Indexed: 02/08/2023] Open
Abstract
Initially discovered by Makuto Kuro-o in 1997, Klotho is a putative aging-suppressor gene when overexpressed and accelerates aging when deleted in mice. Previously, we showed that α-Klotho regulates retinal pigment epithelium (RPE) functions and protects against oxidative stress. However, the mechanisms by which Klotho influences RPE and retinal homeostasis remain elusive. Here, by performing a series of in vitro and in vivo experiments, we demonstrate that Klotho regulates cell viability under oxidative stress, mitochondrial gene expression and activity by inducing the phosphorylation of AMPK and p38MAPK, which in turn phosphorylate and activate CREB and ATF2, respectively, triggering PGC-1α transcription. The inhibition of Klotho in human RPE cells using CRISPR-Cas9 gene editing confirmed that a lack of Klotho negatively affects RPE functions, including mitochondrial activity and cell viability. Proteomic analyses showed that myelin sheath and mitochondrial-related proteins are downregulated in the RPE/retina of Kl-/- compared to WT mice, further supporting our biochemical observations. We conclude that Klotho acts upstream of the AMPK/PGC-1α pathway and regulates RPE/retinal resistance to oxidative stress, mitochondrial function, and gene and protein expressions. Thus, KL decline during aging could negatively impact retinal health, inducing age-related retinal degeneration.
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Mowat FM. Peroxisome Proliferator-Activated Receptor Gamma Coactivator-1Alpha (PGC-1α): A Transcriptional Regulator at the Interface of Aging and Age-Related Macular Degeneration? ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2023; 1415:49-53. [PMID: 37440013 DOI: 10.1007/978-3-031-27681-1_8] [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: 07/14/2023]
Abstract
Human age-related macular degeneration (AMD) is a prevalent age-related disease which causes retinal dysfunction and disability. Genetic and cell culture studies from AMD patients have implicated impaired activity of peroxisome proliferator-activated receptor gamma coactivator-1alpha (PGC-1α). PGC-1α is a transcriptional co-regulator that acts to control a plethora of metabolic processes relevant to AMD pathophysiology including gluconeogenesis, oxidative phosphorylation, and response to oxidative injury. Perturbation of PGC-1α activity in mice causes AMD-like RPE and retinal pathology. There is potential for therapeutic modulation of the PGC-1α pathway in AMD treatment.
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Affiliation(s)
- Freya M Mowat
- Department of Ophthalmology and Visual Sciences (School of Medicine and Public Health), Department of Surgical Sciences (School of Veterinary Medicine), Medical Sciences Center, University of Wisconsin-Madison, Madison, WI, USA.
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8
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Song Y, Wang M, Zhao S, Tian Y, Zhang C. Matrine promotes mitochondrial biosynthesis and reduces oxidative stress in experimental optic neuritis. Front Pharmacol 2022; 13:936632. [PMID: 36238552 PMCID: PMC9552203 DOI: 10.3389/fphar.2022.936632] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Accepted: 08/15/2022] [Indexed: 11/13/2022] Open
Abstract
Optic neuritis (ON), characterized by inflammation of the optic nerve and apoptosis of retinal ganglion cells (RGCs), is one of the leading causes of blindness in patients. Given that RGC, as an energy-intensive cell, is vulnerable to mitochondrial dysfunction, improving mitochondrial function and reducing oxidative stress could protect these cells. Matrine (MAT), an alkaloid derived from Sophoraflavescens, has been shown to regulate immunity and protect neurons in experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis and ON. However, the protective mechanism of MAT on RGCs is largely unknown. In this study, we show that MAT treatment significantly reduced the degree of inflammatory infiltration and demyelination of the optic nerve and increased the survival rate of RGCs. The expression of Sirtuin 1 (SIRT1), a member of an evolutionarily conserved gene family (sirtuins), was upregulated, as well as its downstream molecules Nrf2 and PGC-1α. The percentage of TOMM20-positive cells was also increased remarkably in RGCs after MAT treatment. Thus, our results indicate that MAT protects RGCs from apoptosis, at least in part, by activating SIRT1 to regulate PGC-1α and Nrf2, which, together, promote mitochondrial biosynthesis and reduce the oxidative stress of RGCs.
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Affiliation(s)
- Yifan Song
- Department of Ophthalmology, Peking University Third Hospital, Beijing, China
- Beijing Key Laboratory of Restoration of Damaged Ocular Nerve, Peking University Third Hospital, Beijing, China
| | - Mengru Wang
- Department of Pharmacology, School of Basic Medical Sciences, Zhengzhou University, Zhengzhou, China
| | - Suyan Zhao
- Department of Ophthalmology, Peking University Third Hospital, Beijing, China
- Beijing Key Laboratory of Restoration of Damaged Ocular Nerve, Peking University Third Hospital, Beijing, China
| | - Yanjie Tian
- Department of Ophthalmology, Peking University Third Hospital, Beijing, China
- Beijing Key Laboratory of Restoration of Damaged Ocular Nerve, Peking University Third Hospital, Beijing, China
- *Correspondence: Yanjie Tian,
| | - Chun Zhang
- Department of Ophthalmology, Peking University Third Hospital, Beijing, China
- Beijing Key Laboratory of Restoration of Damaged Ocular Nerve, Peking University Third Hospital, Beijing, China
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Shukal DK, Malaviya PB, Sharma T. Role of the AMPK signalling pathway in the aetiopathogenesis of ocular diseases. Hum Exp Toxicol 2022; 41:9603271211063165. [PMID: 35196887 DOI: 10.1177/09603271211063165] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND AMP-activated protein kinase (AMPK) plays a precise role as a master regulator of cellular energy homeostasis. AMPK is activated in response to the signalling cues that exhaust cellular ATP levels such as hypoxia, ischaemia, glucose depletion and heat shock. As a central regulator of both lipid and glucose metabolism, AMPK is considered to be a potential therapeutic target for the treatment of various diseases, including eye disorders. OBJECTIVE To review all the shreds of evidence concerning the role of the AMPK signalling pathway in the pathogenesis of ocular diseases. METHOD Scientific data search and review of available information evaluating the influence of AMPK signalling on ocular diseases. RESULTS Review highlights the significance of AMPK signalling in the aetiopathogenesis of ocular diseases, including cataract, glaucoma, diabetic retinopathy, retinoblastoma, age-related macular degeneration, corneal diseases, etc. The review also provides the information on the AMPK-associated pathways with reference to ocular disease, which includes mitochondrial biogenesis, autophagy and regulation of inflammatory response. CONCLUSION The study concludes the role of AMPK in ocular diseases. There is growing interest in the therapeutic utilization of the AMPK pathway for ocular disease treatment. Furthermore, inhibition of AMPK signalling might represent more pertinent strategy than AMPK activation for ocular disease treatment. Such information will guide the development of more effective AMPK modulators for ocular diseases.[Formula: see text].
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Affiliation(s)
- Dhaval K Shukal
- 534329Iladevi Cataract and IOL Research Centre, Memnagar, Ahmedabad, Gujarat, India.,76793Manipal Academy of Higher Education, Mangalore, Karnataka, India
| | - Pooja B Malaviya
- 534329Iladevi Cataract and IOL Research Centre, Memnagar, Ahmedabad, Gujarat, India.,76793Manipal Academy of Higher Education, Mangalore, Karnataka, India
| | - Tusha Sharma
- 534329Iladevi Cataract and IOL Research Centre, Memnagar, Ahmedabad, Gujarat, India
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Covering the Role of PGC-1α in the Nervous System. Cells 2021; 11:cells11010111. [PMID: 35011673 PMCID: PMC8750669 DOI: 10.3390/cells11010111] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2021] [Revised: 12/21/2021] [Accepted: 12/28/2021] [Indexed: 12/16/2022] Open
Abstract
The peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) is a well-known transcriptional coactivator involved in mitochondrial biogenesis. PGC-1α is implicated in the pathophysiology of many neurodegenerative disorders; therefore, a deep understanding of its functioning in the nervous system may lead to the development of new therapeutic strategies. The central nervous system (CNS)-specific isoforms of PGC-1α have been recently identified, and many functions of PGC-1α are assigned to the particular cell types of the central nervous system. In the mice CNS, deficiency of PGC-1α disturbed viability and functioning of interneurons and dopaminergic neurons, followed by alterations in inhibitory signaling and behavioral dysfunction. Furthermore, in the ALS rodent model, PGC-1α protects upper motoneurons from neurodegeneration. PGC-1α is engaged in the generation of neuromuscular junctions by lower motoneurons, protection of photoreceptors, and reduction in oxidative stress in sensory neurons. Furthermore, in the glial cells, PGC-1α is essential for the maturation and proliferation of astrocytes, myelination by oligodendrocytes, and mitophagy and autophagy of microglia. PGC-1α is also necessary for synaptogenesis in the developing brain and the generation and maintenance of synapses in postnatal life. This review provides an outlook of recent studies on the role of PGC-1α in various cells in the central nervous system.
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Blasiak J, Pawlowska E, Sobczuk A, Szczepanska J, Kaarniranta K. The Aging Stress Response and Its Implication for AMD Pathogenesis. Int J Mol Sci 2020; 21:ijms21228840. [PMID: 33266495 PMCID: PMC7700335 DOI: 10.3390/ijms21228840] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Revised: 11/12/2020] [Accepted: 11/20/2020] [Indexed: 02/07/2023] Open
Abstract
Aging induces several stress response pathways to counterbalance detrimental changes associated with this process. These pathways include nutrient signaling, proteostasis, mitochondrial quality control and DNA damage response. At the cellular level, these pathways are controlled by evolutionarily conserved signaling molecules, such as 5’AMP-activated protein kinase (AMPK), mechanistic target of rapamycin (mTOR), insulin/insulin-like growth factor 1 (IGF-1) and sirtuins, including SIRT1. Peroxisome proliferation-activated receptor coactivator 1 alpha (PGC-1α), encoded by the PPARGC1A gene, playing an important role in antioxidant defense and mitochondrial biogenesis, may interact with these molecules influencing lifespan and general fitness. Perturbation in the aging stress response may lead to aging-related disorders, including age-related macular degeneration (AMD), the main reason for vision loss in the elderly. This is supported by studies showing an important role of disturbances in mitochondrial metabolism, DDR and autophagy in AMD pathogenesis. In addition, disturbed expression of PGC-1α was shown to associate with AMD. Therefore, the aging stress response may be critical for AMD pathogenesis, and further studies are needed to precisely determine mechanisms underlying its role in AMD. These studies can include research on retinal cells produced from pluripotent stem cells obtained from AMD donors with the mutations, either native or engineered, in the critical genes for the aging stress response, including AMPK, IGF1, MTOR, SIRT1 and PPARGC1A.
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Affiliation(s)
- Janusz Blasiak
- Department of Molecular Genetics, Faculty of Biology and Environmental Protection, University of Lodz, 90-236 Lodz, Poland
- Correspondence: ; Tel.: +48-426354334
| | - Elzbieta Pawlowska
- Department of Orthodontics, Medical University of Lodz, 92-216 Lodz, Poland;
| | - Anna Sobczuk
- Department of Gynaecology and Obstetrics, Medical University of Lodz, 93-338 Lodz, Poland;
| | - Joanna Szczepanska
- Department of Pediatric Dentistry, Medical University of Lodz, 92-216 Lodz, Poland;
| | - Kai Kaarniranta
- Department of Ophthalmology, University of Eastern Finland, 70211 Kuopio, Finland;
- Department of Ophthalmology, Kuopio University Hospital, 70211 Kuopio, Finland
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Kaarniranta K, Uusitalo H, Blasiak J, Felszeghy S, Kannan R, Kauppinen A, Salminen A, Sinha D, Ferrington D. Mechanisms of mitochondrial dysfunction and their impact on age-related macular degeneration. Prog Retin Eye Res 2020; 79:100858. [PMID: 32298788 PMCID: PMC7650008 DOI: 10.1016/j.preteyeres.2020.100858] [Citation(s) in RCA: 246] [Impact Index Per Article: 61.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Revised: 03/18/2020] [Accepted: 03/19/2020] [Indexed: 12/21/2022]
Abstract
Oxidative stress-induced damage to the retinal pigment epithelium (RPE) is considered to be a key factor in age-related macular degeneration (AMD) pathology. RPE cells are constantly exposed to oxidative stress that may lead to the accumulation of damaged cellular proteins, lipids, nucleic acids, and cellular organelles, including mitochondria. The ubiquitin-proteasome and the lysosomal/autophagy pathways are the two major proteolytic systems to remove damaged proteins and organelles. There is increasing evidence that proteostasis is disturbed in RPE as evidenced by lysosomal lipofuscin and extracellular drusen accumulation in AMD. Nuclear factor-erythroid 2-related factor-2 (NFE2L2) and peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1α) are master transcription factors in the regulation of antioxidant enzymes, clearance systems, and biogenesis of mitochondria. The precise cause of RPE degeneration and the onset and progression of AMD are not fully understood. However, mitochondria dysfunction, increased reactive oxygen species (ROS) production, and mitochondrial DNA (mtDNA) damage are observed together with increased protein aggregation and inflammation in AMD. In contrast, functional mitochondria prevent RPE cells damage and suppress inflammation. Here, we will discuss the role of mitochondria in RPE degeneration and AMD pathology focused on mtDNA damage and repair, autophagy/mitophagy signaling, and regulation of inflammation. Mitochondria are putative therapeutic targets to prevent or treat AMD.
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Affiliation(s)
- Kai Kaarniranta
- Department of Ophthalmology, Institute of Clinical Medicine, University of Eastern Finland and Kuopio University Hospital, P.O. Box 1627, FI-70211, Kuopio, Finland.
| | - Hannu Uusitalo
- Faculty of Medicine and Health Technology, Tampere University, Tampere, Finland and Tays Eye Centre, Tampere University Hospital, P.O.Box 2000, 33521 Tampere, Finland
| | - Janusz Blasiak
- Department of Molecular Genetics, Faculty of Biology and Environmental Protection, University of Lodz, 90-236, Lodz, Poland
| | - Szabolcs Felszeghy
- Department of Biomedicine, Faculty of Health Sciences, University of Eastern Finland, P.O. Box 1627, FI-70211, Kuopio, Finland
| | - Ram Kannan
- The Stephen J. Ryan Initiative for Macular Research (RIMR), Doheny Eye Institute, 1355 San Pablo St, Los Angeles, CA, 90033, USA
| | - Anu Kauppinen
- School of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, P.O. Box 1627, FI-70211, Kuopio, Finland
| | - Antero Salminen
- Department of Neurology, Institute of Clinical Medicine, University of Eastern Finland, P.O. Box 1627, FI-70211, Kuopio, Finland
| | - Debasish Sinha
- Glia Research Laboratory, Department of Ophthalmology, University of Pittsburgh, 4401 Penn Avenue, Pittsburgh, PA, PA 15224, USA; Wilmer Eye Institute, The Johns Hopkins University School of Medicine, Room M035 Robert and Clarice Smith Bldg, 400 N Broadway, Baltimore, MD, 21287, USA
| | - Deborah Ferrington
- Department of Ophthalmology and Visual Neurosciences, 2001 6th St SE, University of Minnesota, Minneapolis, MN 55455, USA
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Mulberry supplementation reduces lipid deposition and protects hamster retina from oxLDL damage. J Funct Foods 2020. [DOI: 10.1016/j.jff.2020.104007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
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Han S, Chen J, Hua J, Hu X, Jian S, Zheng G, Wang J, Li H, Yang J, Hejtmancik JF, Qu J, Ma X, Hou L. MITF protects against oxidative damage-induced retinal degeneration by regulating the NRF2 pathway in the retinal pigment epithelium. Redox Biol 2020; 34:101537. [PMID: 32361183 PMCID: PMC7191850 DOI: 10.1016/j.redox.2020.101537] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Revised: 03/29/2020] [Accepted: 04/06/2020] [Indexed: 12/18/2022] Open
Abstract
Oxidative damage is one of the major contributors to retinal degenerative diseases such as age-related macular degeneration (AMD), while RPE mediated antioxidant defense plays an important role in preventing retinopathies. However, the regulatory mechanisms of antioxidant signaling in RPE cells are poorly understood. Here we show that transcription factor MITF regulates the antioxidant response in RPE cells, protecting the neural retina from oxidative damage. In the oxidative stress-induced retinal degeneration mouse model, retinal degeneration in Mitf+/- mice is significantly aggravated compared to WT mice. In contrast, overexpression of Mitf in Dct-Mitf transgenic mice and AAV mediated overexpression in RPE cells protect the neural retina against oxidative damage. Mechanistically, MITF both directly regulates the transcription of NRF2, a master regulator of antioxidant signaling, and promotes its nuclear translocation. Furthermore, specific overexpression of NRF2 in Mitf+/- RPE cells activates antioxidant signaling and partially protects the retina from oxidative damage. Taken together, our findings demonstrate the regulation of NRF2 by MITF in RPE cells and provide new insights into potential therapeutic approaches for prevention of oxidative damage diseases. MITF haploinsufficiency exacerbates oxidative stress-induced retinal degeneration. Specific overexpression of MITF in RPE cells protects retinas from oxidative damage in vivo. MITF directly regulates the transcription and nuclear translocation of NRF2. Partial rescue of retinal oxidative damage in Mitf ±mice by gene transfer mediated RPE cell specific expression of NRF2.
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Affiliation(s)
- Shuxian Han
- Laboratory of Developmental Cell Biology and Disease, School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, China; State Key Laboratory Cultivation Base and Key Laboratory of Vision Science of Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology, Wenzhou Medical University, Wenzhou, 325003, China
| | - Jianjun Chen
- Birth defect group, Translation Research Institute of Brain and Brain-Like Intelligence, Shanghai Fourth People's Hospital Affiliated to Tongji University School of Medicine, Shanghai, 200081, China
| | - Jiajia Hua
- Laboratory of Developmental Cell Biology and Disease, School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, China; Department of Ophthalmology, Affiliated Hospital of Jining Medical University, Jining, Shandong, 272029, China
| | - Xiaojuan Hu
- Laboratory of Developmental Cell Biology and Disease, School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, China
| | - Shuhui Jian
- Laboratory of Developmental Cell Biology and Disease, School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, China
| | - Guoxiao Zheng
- Laboratory of Developmental Cell Biology and Disease, School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, China
| | - Jing Wang
- Laboratory of Developmental Cell Biology and Disease, School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, China; State Key Laboratory Cultivation Base and Key Laboratory of Vision Science of Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology, Wenzhou Medical University, Wenzhou, 325003, China
| | - Huirong Li
- Laboratory of Developmental Cell Biology and Disease, School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, China; State Key Laboratory Cultivation Base and Key Laboratory of Vision Science of Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology, Wenzhou Medical University, Wenzhou, 325003, China
| | - Jinglei Yang
- State Key Laboratory Cultivation Base and Key Laboratory of Vision Science of Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology, Wenzhou Medical University, Wenzhou, 325003, China
| | - J Fielding Hejtmancik
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Jia Qu
- State Key Laboratory Cultivation Base and Key Laboratory of Vision Science of Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology, Wenzhou Medical University, Wenzhou, 325003, China.
| | - Xiaoyin Ma
- Laboratory of Developmental Cell Biology and Disease, School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, China; State Key Laboratory Cultivation Base and Key Laboratory of Vision Science of Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology, Wenzhou Medical University, Wenzhou, 325003, China.
| | - Ling Hou
- Laboratory of Developmental Cell Biology and Disease, School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, China; State Key Laboratory Cultivation Base and Key Laboratory of Vision Science of Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology, Wenzhou Medical University, Wenzhou, 325003, China
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15
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The Emerging Role of Senescence in Ocular Disease. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2020; 2020:2583601. [PMID: 32215170 PMCID: PMC7085400 DOI: 10.1155/2020/2583601] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Accepted: 02/14/2020] [Indexed: 02/07/2023]
Abstract
Cellular senescence is a state of irreversible cell cycle arrest in response to an array of cellular stresses. An important role for senescence has been shown for a number of pathophysiological conditions that include cardiovascular disease, pulmonary fibrosis, and diseases of the skin. However, whether senescence contributes to the progression of age-related macular degeneration (AMD) has not been studied in detail so far and the present review describes the recent research on this topic. We present an overview of the types of senescence, pathways of senescence, senescence-associated secretory phenotype (SASP), the role of mitochondria, and their functional implications along with antisenescent therapies. As a central mechanism, senescent cells can impact the surrounding tissue microenvironment via the secretion of a pool of bioactive molecules, termed the SASP. An updated summary of a number of new members of the ever-growing SASP family is presented. Further, we introduce the significance of mechanisms by which mitochondria may participate in the development of cellular senescence. Emerging evidence shows that extracellular vesicles (EVs) are important mediators of the effects of senescent cells on their microenvironment. Based on recent studies, there is reasonable evidence that senescence could be a modifiable factor, and hence, it may be possible to delay age-related diseases by modulating basic aging mechanisms using SASP inhibitors/senolytic drugs. Thus, antisenescent therapies in aging and age-related diseases appear to have a promising potential.
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16
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Fu Z, Sun Y, Cakir B, Tomita Y, Huang S, Wang Z, Liu CH, S. Cho S, Britton W, S. Kern T, Antonetti DA, Hellström A, E.H. Smith L. Targeting Neurovascular Interaction in Retinal Disorders. Int J Mol Sci 2020; 21:E1503. [PMID: 32098361 PMCID: PMC7073081 DOI: 10.3390/ijms21041503] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Revised: 02/13/2020] [Accepted: 02/21/2020] [Indexed: 02/07/2023] Open
Abstract
The tightly structured neural retina has a unique vascular network comprised of three interconnected plexuses in the inner retina (and choroid for outer retina), which provide oxygen and nutrients to neurons to maintain normal function. Clinical and experimental evidence suggests that neuronal metabolic needs control both normal retinal vascular development and pathological aberrant vascular growth. Particularly, photoreceptors, with the highest density of mitochondria in the body, regulate retinal vascular development by modulating angiogenic and inflammatory factors. Photoreceptor metabolic dysfunction, oxidative stress, and inflammation may cause adaptive but ultimately pathological retinal vascular responses, leading to blindness. Here we focus on the factors involved in neurovascular interactions, which are potential therapeutic targets to decrease energy demand and/or to increase energy production for neovascular retinal disorders.
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Affiliation(s)
- Zhongjie Fu
- Department of Ophthalmology, Boston Children’s Hospital, Harvard Medical School, Boston, MA 02115, USA; (Z.F.); (Y.S.); (B.C.); (Y.T.); (S.H.); (Z.W.); (C.-H.L.); (S.S.C.); (W.B.)
- Manton Center for Orphan Disease, Boston Children’s Hospital, Boston, MA 02115, USA
| | - Ye Sun
- Department of Ophthalmology, Boston Children’s Hospital, Harvard Medical School, Boston, MA 02115, USA; (Z.F.); (Y.S.); (B.C.); (Y.T.); (S.H.); (Z.W.); (C.-H.L.); (S.S.C.); (W.B.)
| | - Bertan Cakir
- Department of Ophthalmology, Boston Children’s Hospital, Harvard Medical School, Boston, MA 02115, USA; (Z.F.); (Y.S.); (B.C.); (Y.T.); (S.H.); (Z.W.); (C.-H.L.); (S.S.C.); (W.B.)
| | - Yohei Tomita
- Department of Ophthalmology, Boston Children’s Hospital, Harvard Medical School, Boston, MA 02115, USA; (Z.F.); (Y.S.); (B.C.); (Y.T.); (S.H.); (Z.W.); (C.-H.L.); (S.S.C.); (W.B.)
| | - Shuo Huang
- Department of Ophthalmology, Boston Children’s Hospital, Harvard Medical School, Boston, MA 02115, USA; (Z.F.); (Y.S.); (B.C.); (Y.T.); (S.H.); (Z.W.); (C.-H.L.); (S.S.C.); (W.B.)
| | - Zhongxiao Wang
- Department of Ophthalmology, Boston Children’s Hospital, Harvard Medical School, Boston, MA 02115, USA; (Z.F.); (Y.S.); (B.C.); (Y.T.); (S.H.); (Z.W.); (C.-H.L.); (S.S.C.); (W.B.)
| | - Chi-Hsiu Liu
- Department of Ophthalmology, Boston Children’s Hospital, Harvard Medical School, Boston, MA 02115, USA; (Z.F.); (Y.S.); (B.C.); (Y.T.); (S.H.); (Z.W.); (C.-H.L.); (S.S.C.); (W.B.)
| | - Steve S. Cho
- Department of Ophthalmology, Boston Children’s Hospital, Harvard Medical School, Boston, MA 02115, USA; (Z.F.); (Y.S.); (B.C.); (Y.T.); (S.H.); (Z.W.); (C.-H.L.); (S.S.C.); (W.B.)
| | - William Britton
- Department of Ophthalmology, Boston Children’s Hospital, Harvard Medical School, Boston, MA 02115, USA; (Z.F.); (Y.S.); (B.C.); (Y.T.); (S.H.); (Z.W.); (C.-H.L.); (S.S.C.); (W.B.)
| | - Timothy S. Kern
- Center for Translational Vision Research, Gavin Herbert Eye Institute, Irvine, CA 92697, USA;
| | - David A. Antonetti
- Kellogg Eye Center, Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, MI 48105, USA;
| | - Ann Hellström
- Section for Ophthalmology, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, 405 30 Göteborg, Sweden;
| | - Lois E.H. Smith
- Department of Ophthalmology, Boston Children’s Hospital, Harvard Medical School, Boston, MA 02115, USA; (Z.F.); (Y.S.); (B.C.); (Y.T.); (S.H.); (Z.W.); (C.-H.L.); (S.S.C.); (W.B.)
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17
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Zhang M, Jiang N, Chu Y, Postnikova O, Varghese R, Horvath A, Cheema AK, Golestaneh N. Dysregulated metabolic pathways in age-related macular degeneration. Sci Rep 2020; 10:2464. [PMID: 32051464 PMCID: PMC7016007 DOI: 10.1038/s41598-020-59244-4] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Accepted: 01/27/2020] [Indexed: 01/03/2023] Open
Abstract
Age-related macular degeneration is a major cause of vision impairment in the Western world among people of 55 years and older. Recently we have shown that autophagy is dysfunctional in the retinal pigment epithelium (RPE) of the AMD donor eyes (AMD RPE). We also showed increased reactive oxygen (ROS) production, increased cytoplasmic glycogen accumulation, mitochondrial dysfunction and disintegration, and enlarged and annular LAMP-1-positive organelles in AMD RPE. However, the underlying mechanisms inducing these abnormalities remain to be elucidated. Here, by performing a comprehensive study, we show increased PAPR2 expression, deceased NAD+, and SIRT1, increased PGC-1α acetylation (inactive form), lower AMPK activity, and overactive mTOR pathway in AMD RPE as compared to normal RPE. Metabolomics and lipidomics revealed dysregulated metabolites in AMD RPE as compared to normal RPE, including glycerophospholipid metabolism, involved in autophagy, lipid, and protein metabolisms, glutathione, guanosine, and L-glutamic acid, which are implicated in protection against oxidative stress and neurotoxicity, further supporting our observations. Our data show dysregulated metabolic pathways as important contributors to AMD pathophysiology, and facilitate the development of new treatment strategies for this debilitating disease of the visual system.
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Affiliation(s)
- Meng Zhang
- Department of Ophthalmology, Georgetown University Medical Center, Washington, DC, 20057, USA
| | - Nisi Jiang
- Department of Ophthalmology, Georgetown University Medical Center, Washington, DC, 20057, USA
| | - Yi Chu
- Department of Ophthalmology, Georgetown University Medical Center, Washington, DC, 20057, USA
| | - Olga Postnikova
- Laboratory of Retinal Cell & Molecular Biology (HNW28), NIH/NEI, Bethesda, MD, 20814, USA
| | - Rency Varghese
- Department of Oncology, Georgetown University Medical Center, Washington, DC, 20057, USA
| | - Anelia Horvath
- Department of Pharmacology and Physiology, Department of Biochemistry and Molecular Medicine, George Washington University, Washington, DC, 20037, USA
| | - Amrita K Cheema
- Department of Biochemistry and Molecular & Cellular Biology, Georgetown University Medical Center, Washington, DC, 20057, USA.,Department of Oncology, Georgetown University Medical Center, Washington, DC, 20057, USA
| | - Nady Golestaneh
- Department of Ophthalmology, Georgetown University Medical Center, Washington, DC, 20057, USA. .,Department of Neurology, Georgetown University Medical Center, Washington, DC, 20057, USA. .,Department of Biochemistry and Molecular & Cellular Biology, Georgetown University Medical Center, Washington, DC, 20057, USA.
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18
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Gill JF, Delezie J, Santos G, McGuirk S, Schnyder S, Frank S, Rausch M, St‐Pierre J, Handschin C. Peroxisome proliferator-activated receptor γ coactivator 1α regulates mitochondrial calcium homeostasis, sarcoplasmic reticulum stress, and cell death to mitigate skeletal muscle aging. Aging Cell 2019; 18:e12993. [PMID: 31290266 PMCID: PMC6718523 DOI: 10.1111/acel.12993] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Revised: 04/26/2019] [Accepted: 05/27/2019] [Indexed: 11/28/2022] Open
Abstract
Age-related impairment of muscle function severely affects the health of an increasing elderly population. While causality and the underlying mechanisms remain poorly understood, exercise is an efficient intervention to blunt these aging effects. We thus investigated the role of the peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α), a potent regulator of mitochondrial function and exercise adaptation, in skeletal muscle during aging. We demonstrate that PGC-1α overexpression improves mitochondrial dynamics and calcium buffering in an estrogen-related receptor α-dependent manner. Moreover, we show that sarcoplasmic reticulum stress is attenuated by PGC-1α. As a result, PGC-1α prevents tubular aggregate formation and cell death pathway activation in old muscle. Similarly, the pro-apoptotic effects of ceramide and thapsigargin were blunted by PGC-1α in muscle cells. Accordingly, mice with muscle-specific gain-of-function and loss-of-function of PGC-1α exhibit a delayed and premature aging phenotype, respectively. Together, our data reveal a key protective effect of PGC-1α on muscle function and overall health span in aging.
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Affiliation(s)
- Jonathan F. Gill
- Biozentrum, Division of Pharmacology/Neurobiology University of Basel Basel Switzerland
| | - Julien Delezie
- Biozentrum, Division of Pharmacology/Neurobiology University of Basel Basel Switzerland
| | - Gesa Santos
- Biozentrum, Division of Pharmacology/Neurobiology University of Basel Basel Switzerland
| | - Shawn McGuirk
- Department of Biochemistry, Rosalind and Morris Goodman Cancer Centre McGill University Montreal Quebec Canada
| | - Svenia Schnyder
- Biozentrum, Division of Pharmacology/Neurobiology University of Basel Basel Switzerland
| | - Stephan Frank
- Division of Neuropathology, Institute of Pathology, University Hospital Basel University of Basel Basel Switzerland
| | - Martin Rausch
- Biotherapeutic and Analytical Technologies Novartis Institutes for BioMedical Research (NIBR) Basel Switzerland
| | - Julie St‐Pierre
- Department of Biochemistry, Rosalind and Morris Goodman Cancer Centre McGill University Montreal Quebec Canada
| | - Christoph Handschin
- Biozentrum, Division of Pharmacology/Neurobiology University of Basel Basel Switzerland
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19
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Rosales MAB, Shu DY, Iacovelli J, Saint-Geniez M. Loss of PGC-1α in RPE induces mesenchymal transition and promotes retinal degeneration. Life Sci Alliance 2019; 2:2/3/e201800212. [PMID: 31101737 PMCID: PMC6526284 DOI: 10.26508/lsa.201800212] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Revised: 05/07/2019] [Accepted: 05/09/2019] [Indexed: 01/07/2023] Open
Abstract
Sustained loss of PGC-1α in RPE cells triggers mitochondrial/autophagic dysfunction and oxidative damage resulting in epithelial dedifferentiation and mesenchymal transition. RPE dysfunction caused by deletion of the PGC-1 coactivators in vivo causes retinal degeneration. The retinal pigment epithelium (RPE) supports visual processing and photoreceptor homeostasis via energetically demanding cellular functions. Here, we describe the consequences of repressing peroxisome proliferator-activated receptor γ coactivator-1 α (PGC-1α), a master regulator of mitochondrial function and biogenesis, on RPE epithelial integrity. The sustained silencing of PGC-1α in differentiating human RPE cells affected mitochondria/autophagy function, redox state, and impaired energy sensor activity ultimately inducing epithelial to mesenchymal transition (EMT). Adult conditional knockout of PGC-1 coactivators in mice resulted in rapid RPE dysfunction and transdifferentiation associated with severe photoreceptor degeneration. RPE anomalies were characteristic of autophagic defect and mesenchymal transition comparable with the ones observed in age-related macular degeneration. These findings demonstrate that PGC-1α is required to maintain the functional and phenotypic status of RPE by supporting the cells’ oxidative metabolism and autophagy-mediated repression of EMT.
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Affiliation(s)
- Mariana Aparecida Brunini Rosales
- Schepens Eye Research Institute of Massachusetts Eye and Ear, Boston, MA.,Department of Ophthalmology, Harvard Medical School, Boston, MA
| | - Daisy Y Shu
- Schepens Eye Research Institute of Massachusetts Eye and Ear, Boston, MA.,Department of Ophthalmology, Harvard Medical School, Boston, MA
| | - Jared Iacovelli
- Schepens Eye Research Institute of Massachusetts Eye and Ear, Boston, MA.,Department of Ophthalmology, Harvard Medical School, Boston, MA
| | - Magali Saint-Geniez
- Schepens Eye Research Institute of Massachusetts Eye and Ear, Boston, MA .,Department of Ophthalmology, Harvard Medical School, Boston, MA
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20
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Pharmaceutical Induction of PGC-1 α Promotes Retinal Pigment Epithelial Cell Metabolism and Protects against Oxidative Damage. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2018; 2018:9248640. [PMID: 30524663 PMCID: PMC6247391 DOI: 10.1155/2018/9248640] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Accepted: 09/14/2018] [Indexed: 01/05/2023]
Abstract
Retinal pigment epithelium (RPE) dysfunction due to accumulation of reactive oxygen species and oxidative damage is a key event in the development of age-related macular degeneration (AMD). Here, we examine the therapeutic potential of ZLN005, a selective PGC-1α transcriptional regulator, in protecting RPE from cytotoxic oxidative damage. Gene expression analysis on ARPE-19 cells treated with ZLN005 shows robust upregulation of PGC-1α and its associated transcription factors, antioxidant enzymes, and mitochondrial genes. Energetic profiling shows that ZLN005 treatment enhances RPE mitochondrial function by increasing basal and maximal respiration rates, and spare respiratory capacity. In addition, ZLN005 robustly protects ARPE-19 cells from cell death caused by H2O2, ox-LDL, and NaIO3 without exhibiting any cytotoxicity under basal conditions. ZLN005 protection against H2O2-mediated cell death was lost in PGC-1α-silenced cells. Our data indicates that ZLN005 efficiently protects RPE cells from oxidative damage through selective induction of PGC-1α and its target antioxidant enzymes. ZLN005 may serve as a novel therapeutic agent for retinal diseases associated with RPE dystrophies.
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21
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Felszeghy S, Viiri J, Paterno JJ, Hyttinen JMT, Koskela A, Chen M, Leinonen H, Tanila H, Kivinen N, Koistinen A, Toropainen E, Amadio M, Smedowski A, Reinisalo M, Winiarczyk M, Mackiewicz J, Mutikainen M, Ruotsalainen AK, Kettunen M, Jokivarsi K, Sinha D, Kinnunen K, Petrovski G, Blasiak J, Bjørkøy G, Koskelainen A, Skottman H, Urtti A, Salminen A, Kannan R, Ferrington DA, Xu H, Levonen AL, Tavi P, Kauppinen A, Kaarniranta K. Loss of NRF-2 and PGC-1α genes leads to retinal pigment epithelium damage resembling dry age-related macular degeneration. Redox Biol 2018; 20:1-12. [PMID: 30253279 PMCID: PMC6156745 DOI: 10.1016/j.redox.2018.09.011] [Citation(s) in RCA: 113] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Revised: 09/06/2018] [Accepted: 09/13/2018] [Indexed: 12/30/2022] Open
Abstract
Age-related macular degeneration (AMD) is a multi-factorial disease that is the leading cause of irreversible and severe vision loss in the developed countries. It has been suggested that the pathogenesis of dry AMD involves impaired protein degradation in retinal pigment epithelial cells (RPE). RPE cells are constantly exposed to oxidative stress that may lead to the accumulation of damaged cellular proteins, DNA and lipids and evoke tissue deterioration during the aging process. The ubiquitin-proteasome pathway and the lysosomal/autophagosomal pathway are the two major proteolytic systems in eukaryotic cells. NRF-2 (nuclear factor-erythroid 2-related factor-2) and PGC-1α (peroxisome proliferator-activated receptor gamma coactivator-1 alpha) are master transcription factors in the regulation of cellular detoxification. We investigated the role of NRF-2 and PGC-1α in the regulation of RPE cell structure and function by using global double knockout (dKO) mice. The NRF-2/PGC-1α dKO mice exhibited significant age-dependent RPE degeneration, accumulation of the oxidative stress marker, 4-HNE (4-hydroxynonenal), the endoplasmic reticulum stress markers GRP78 (glucose-regulated protein 78) and ATF4 (activating transcription factor 4), and damaged mitochondria. Moreover, levels of protein ubiquitination and autophagy markers p62/SQSTM1 (sequestosome 1), Beclin-1 and LC3B (microtubule associated protein 1 light chain 3 beta) were significantly increased together with the Iba-1 (ionized calcium binding adaptor molecule 1) mononuclear phagocyte marker and an enlargement of RPE size. These histopathological changes of RPE were accompanied by photoreceptor dysmorphology and vision loss as revealed by electroretinography. Consequently, these novel findings suggest that the NRF-2/PGC-1α dKO mouse is a valuable model for investigating the role of proteasomal and autophagy clearance in the RPE and in the development of dry AMD. NRF-2/PGC-1α dKO mouse model shows a dry AMD-like phenotype. Loss of NRF-2/PGC-1α genes increased oxidative and ER stress in RPE cells. High oxidative stress was associated with impaired autophagy and proteasomal clearance. The pathology becomes manifest as an age-related loss of photoreceptor function.
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Affiliation(s)
- Szabolcs Felszeghy
- Institute of Dentistry, University of Eastern Finland, Kuopio, Finland; Institute of Biomedicine, University of Eastern Finland, Kuopio, Finland
| | - Johanna Viiri
- Department of Ophthalmology, University of Eastern Finland, Kuopio, Finland
| | - Jussi J Paterno
- Department of Ophthalmology, University of Eastern Finland, Kuopio, Finland; Department of Ophthalmology, Kuopio University Hospital, Kuopio, Finland
| | - Juha M T Hyttinen
- Department of Ophthalmology, University of Eastern Finland, Kuopio, Finland
| | - Ali Koskela
- Department of Ophthalmology, University of Eastern Finland, Kuopio, Finland
| | - Mei Chen
- The Wellcome-Wolfson Institute of Experimental Medicine Queen's University Belfast, Belfast, UK
| | - Henri Leinonen
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Heikki Tanila
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Niko Kivinen
- Department of Ophthalmology, University of Eastern Finland, Kuopio, Finland; Department of Ophthalmology, Kuopio University Hospital, Kuopio, Finland
| | - Arto Koistinen
- SIB Labs, University of Eastern Finland, Kuopio, Finland
| | - Elisa Toropainen
- School of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, Kuopio, Finland
| | - Marialaura Amadio
- Department of Drug Sciences, Section of Pharmacology, University of Pavia, Pavia, Italy
| | - Adrian Smedowski
- Chair and Department of Physiology, School of Medicine in Katowice, Medical University of Silesia, Katowice, Poland
| | - Mika Reinisalo
- Department of Ophthalmology, University of Eastern Finland, Kuopio, Finland; School of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, Kuopio, Finland
| | - Mateusz Winiarczyk
- Department of Epizootiology, University of Life Sciences of Lublin, Poland; Department of Vitreoretinal Surgery, Medical University of Lublin, Poland
| | - Jerzy Mackiewicz
- Department of Vitreoretinal Surgery, Medical University of Lublin, Poland
| | - Maija Mutikainen
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Anna-Kaisa Ruotsalainen
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Mikko Kettunen
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Kimmo Jokivarsi
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Debasish Sinha
- The Wilmer Eye Institute, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Kati Kinnunen
- Department of Ophthalmology, Kuopio University Hospital, Kuopio, Finland
| | - Goran Petrovski
- Centre of Eye Research, Department of Ophthalmology, Oslo University Hospital, University of Oslo, Oslo, Norway
| | - Janusz Blasiak
- Department of Molecular Genetics, University of Lodz, Lodz, Poland
| | - Geir Bjørkøy
- Centre of Molecular Inflammation Research and Department of Cancer Research and Molecular Medicine; Norwegian University of Science and Technology and Department of Technology; University College of Sør-Trøndelag, Trondheim, Norway
| | - Ari Koskelainen
- Department of Neuroscience and Biomedical Engineering, Aalto University School of Science, Aalto, Finland
| | - Heli Skottman
- Faculty of Medicine and Life Sciences, BioMediTech Institute, University of Tampere, Tampere, Finland
| | - Arto Urtti
- School of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, Kuopio, Finland; Centre for Drug Research, Division of Pharmaceutical Biosciences, University of Helsinki, Helsinki, Finland
| | - Antero Salminen
- Department of Neurology, University of Eastern Finland, Kuopio, Finland
| | - Ram Kannan
- Arnold and Mabel Beckman Macular Research Center, Doheny Eye Institute, Los Angeles, CA, USA
| | - Deborah A Ferrington
- Department of Ophthalmology and Visual Neurosciences, University of Minnesota, Minneapolis, USA
| | - Heping Xu
- The Wellcome-Wolfson Institute of Experimental Medicine Queen's University Belfast, Belfast, UK
| | - Anna-Liisa Levonen
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Pasi Tavi
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Anu Kauppinen
- School of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, Kuopio, Finland
| | - Kai Kaarniranta
- Department of Ophthalmology, University of Eastern Finland, Kuopio, Finland; Department of Ophthalmology, Kuopio University Hospital, Kuopio, Finland.
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22
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Hu CB, Sui BD, Wang BY, Li G, Hu CH, Zheng CX, Du FY, Zhu CH, Li HB, Feng Y, Jin Y, Yu XR. NDRG2 suppression as a molecular hallmark of photoreceptor-specific cell death in the mouse retina. Cell Death Discov 2018; 4:32. [PMID: 30245855 PMCID: PMC6135825 DOI: 10.1038/s41420-018-0101-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Accepted: 08/23/2018] [Indexed: 02/07/2023] Open
Abstract
Photoreceptor cell death is recognized as the key pathogenesis of retinal degeneration, but the molecular basis underlying photoreceptor-specific cell loss in retinal damaging conditions is virtually unknown. The N-myc downstream regulated gene (NDRG) family has recently been reported to regulate cell viability, in particular NDRG1 has been uncovered expression in photoreceptor cells. Accordingly, we herein examined the potential roles of NDRGs in mediating photoreceptor-specific cell loss in retinal damages. By using mouse models of retinal degeneration and the 661 W photoreceptor cell line, we showed that photoreceptor cells are indeed highly sensitive to light exposure and the related oxidative stress, and that photoreceptor cells are even selectively diminished by phototoxins of the alkylating agent N-Methyl-N-nitrosourea (MNU). Unexpectedly, we discovered that of all the NDRG family members, NDRG2, but not the originally hypothesized NDRG1 or other NDRG subtypes, was selectively expressed and specifically responded to retinal damaging conditions in photoreceptor cells. Furthermore, functional experiments proved that NDRG2 was essential for photoreceptor cell viability, which could be attributed to NDRG2 control of the photo-oxidative stress, and that it was the suppression of NDRG2 which led to photoreceptor cell loss in damaging conditions. More importantly, NDRG2 preservation contributed to photoreceptor-specific cell maintenance and retinal protection both in vitro and in vivo. Our findings revealed a previously unrecognized role of NDRG2 in mediating photoreceptor cell homeostasis and established for the first time the molecular hallmark of photoreceptor-specific cell death as NDRG2 suppression, shedding light on improved understanding and therapy of retinal degeneration.
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Affiliation(s)
- Cheng-Biao Hu
- 1Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, 710061 Xi'an, Shaanxi China.,2Key Laboratory of Environment and Genes Related to Diseases (Xi'an Jiaotong University), Ministry of Education, Xi'an, Shaanxi Sheng China
| | - Bing-Dong Sui
- 3State Key Laboratory of Military Stomatology, Center for Tissue Engineering, Fourth Military Medical University, 710032 Xi'an, Shaanxi China.,Xi'an Institute of Tissue Engineering and Regenerative Medicine, 710032 Xi'an, Shaanxi China
| | - Bao-Ying Wang
- 1Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, 710061 Xi'an, Shaanxi China.,2Key Laboratory of Environment and Genes Related to Diseases (Xi'an Jiaotong University), Ministry of Education, Xi'an, Shaanxi Sheng China
| | - Gao Li
- Xi'an Institute of Tissue Engineering and Regenerative Medicine, 710032 Xi'an, Shaanxi China.,5Department of Stomatology, The People's Hospital of Zhangqiu City, 250200 Zhangqiu, Shandong China
| | - Cheng-Hu Hu
- 3State Key Laboratory of Military Stomatology, Center for Tissue Engineering, Fourth Military Medical University, 710032 Xi'an, Shaanxi China.,Xi'an Institute of Tissue Engineering and Regenerative Medicine, 710032 Xi'an, Shaanxi China
| | - Chen-Xi Zheng
- 3State Key Laboratory of Military Stomatology, Center for Tissue Engineering, Fourth Military Medical University, 710032 Xi'an, Shaanxi China.,Xi'an Institute of Tissue Engineering and Regenerative Medicine, 710032 Xi'an, Shaanxi China
| | - Fang-Ying Du
- 1Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, 710061 Xi'an, Shaanxi China.,2Key Laboratory of Environment and Genes Related to Diseases (Xi'an Jiaotong University), Ministry of Education, Xi'an, Shaanxi Sheng China
| | - Chun-Hui Zhu
- 1Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, 710061 Xi'an, Shaanxi China.,2Key Laboratory of Environment and Genes Related to Diseases (Xi'an Jiaotong University), Ministry of Education, Xi'an, Shaanxi Sheng China
| | - Hong-Bo Li
- 1Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, 710061 Xi'an, Shaanxi China.,2Key Laboratory of Environment and Genes Related to Diseases (Xi'an Jiaotong University), Ministry of Education, Xi'an, Shaanxi Sheng China
| | - Yan Feng
- 1Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, 710061 Xi'an, Shaanxi China.,2Key Laboratory of Environment and Genes Related to Diseases (Xi'an Jiaotong University), Ministry of Education, Xi'an, Shaanxi Sheng China
| | - Yan Jin
- 3State Key Laboratory of Military Stomatology, Center for Tissue Engineering, Fourth Military Medical University, 710032 Xi'an, Shaanxi China.,Xi'an Institute of Tissue Engineering and Regenerative Medicine, 710032 Xi'an, Shaanxi China
| | - Xiao-Rui Yu
- 1Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, 710061 Xi'an, Shaanxi China.,2Key Laboratory of Environment and Genes Related to Diseases (Xi'an Jiaotong University), Ministry of Education, Xi'an, Shaanxi Sheng China
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Zhang M, Chu Y, Mowery J, Konkel B, Galli S, Theos AC, Golestaneh N. Pgc-1α repression and high-fat diet induce age-related macular degeneration-like phenotypes in mice. Dis Model Mech 2018; 11:dmm.032698. [PMID: 29925537 PMCID: PMC6176989 DOI: 10.1242/dmm.032698] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2017] [Accepted: 06/13/2018] [Indexed: 12/28/2022] Open
Abstract
Age-related macular degeneration (AMD) is the major cause of blindness in the elderly in developed countries and its prevalence is increasing with the aging population. AMD initially affects the retinal pigment epithelium (RPE) and gradually leads to secondary photoreceptor degeneration. Recent studies have associated mitochondrial damage with AMD, and we have observed mitochondrial and autophagic dysfunction and repressed peroxisome proliferator-activated receptor-γ coactivator 1α (PGC-1α; also known as Ppargc1a) in native RPE from AMD donor eyes and their respective induced pluripotent stem cell-derived RPE. To further investigate the effect of PGC-1α repression, we have established a mouse model by feeding Pgc-1α+/− mice with a high-fat diet (HFD) and investigated RPE and retinal health. We show that when mice expressing lower levels of Pgc-1α are exposed to HFD, they present AMD-like abnormalities in RPE and retinal morphology and function. These abnormalities include basal laminar deposits, thickening of Bruch's membrane with drusen marker-containing deposits, RPE and photoreceptor degeneration, decreased mitochondrial activity, increased levels of reactive oxygen species, decreased autophagy dynamics/flux, and increased inflammatory response in the RPE and retina. Our study shows that Pgc-1α is important in outer retina biology and that Pgc-1α+/− mice fed with HFD provide a promising model to study AMD, opening doors for novel treatment strategies. Summary: A new mouse model has been established that exhibits characteristics of human age-related macular degeneration; the model will facilitate further studies of AMD disease mechanisms.
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Affiliation(s)
- Meng Zhang
- Department of Ophthalmology, Georgetown University Medical Center, Washington, DC 20057, USA
| | - Yi Chu
- Department of Ophthalmology, Georgetown University Medical Center, Washington, DC 20057, USA
| | - Joseph Mowery
- Electron and Confocal Microscopy Unit, USDA Agricultural Research Service, Beltsville, MD 20705, USA
| | - Brandon Konkel
- Department of Biochemistry and Molecular and Cellular Biology, Georgetown University Medical Center, Washington, DC 20057, USA
| | - Susana Galli
- Department of Biochemistry and Molecular and Cellular Biology, Georgetown University Medical Center, Washington, DC 20057, USA
| | - Alexander C Theos
- Department of Human Science, Georgetown University, Washington, DC 20057, USA
| | - Nady Golestaneh
- Department of Ophthalmology, Georgetown University Medical Center, Washington, DC 20057, USA .,Department of Biochemistry and Molecular and Cellular Biology, Georgetown University Medical Center, Washington, DC 20057, USA.,Department of Neurology, Georgetown University Medical Center, Washington, DC 20057, USA
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24
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Kaarniranta K, Kajdanek J, Morawiec J, Pawlowska E, Blasiak J. PGC-1α Protects RPE Cells of the Aging Retina against Oxidative Stress-Induced Degeneration through the Regulation of Senescence and Mitochondrial Quality Control. The Significance for AMD Pathogenesis. Int J Mol Sci 2018; 19:ijms19082317. [PMID: 30087287 PMCID: PMC6121367 DOI: 10.3390/ijms19082317] [Citation(s) in RCA: 76] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Revised: 07/18/2018] [Accepted: 08/05/2018] [Indexed: 02/07/2023] Open
Abstract
PGC-1α (peroxisome proliferator-activated receptor gamma coactivator 1-alpha) is a transcriptional coactivator of many genes involved in energy management and mitochondrial biogenesis. PGC-1α expression is associated with cellular senescence, organismal aging, and many age-related diseases, including AMD (age-related macular degeneration), an important global issue concerning vision loss. We and others have developed a model of AMD pathogenesis, in which stress-induced senescence of retinal pigment epithelium (RPE) cells leads to AMD-related pathological changes. PGC-1α can decrease oxidative stress, a key factor of AMD pathogenesis related to senescence, through upregulation of antioxidant enzymes and DNA damage response. PGC-1α is an important regulator of VEGF (vascular endothelial growth factor), which is targeted in the therapy of wet AMD, the most devastating form of AMD. Dysfunction of mitochondria induces cellular senescence associated with AMD pathogenesis. PGC-1α can improve mitochondrial biogenesis and negatively regulate senescence, although this function of PGC-1α in AMD needs further studies. Post-translational modifications of PGC-1α by AMPK (AMP kinase) and SIRT1 (sirtuin 1) are crucial for its activation and important in AMD pathogenesis.
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Affiliation(s)
- Kai Kaarniranta
- Department of Ophthalmology, University of Eastern Finland, 70211 Kuopio, Finland.
- Department of Ophthalmology, Kuopio University Hospital, 70029 Kuopio, Finland.
| | - Jakub Kajdanek
- Department of Molecular Genetics, Faculty of Biology and Environmental Protection, University of Lodz, Pomorska 141/143, 90-236 Lodz, Poland.
| | - Jan Morawiec
- Department of General and Colorectal Surgery, Medical University of Lodz, Pl. Hallera 1, 90-647 Lodz, Poland.
| | - Elzbieta Pawlowska
- Department of Orthodontics, Medical University of Lodz, Pomorska 251, 92-216 Lodz, Poland.
| | - Janusz Blasiak
- Department of Molecular Genetics, Faculty of Biology and Environmental Protection, University of Lodz, Pomorska 141/143, 90-236 Lodz, Poland.
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25
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Hyttinen JMT, Viiri J, Kaarniranta K, Błasiak J. Mitochondrial quality control in AMD: does mitophagy play a pivotal role? Cell Mol Life Sci 2018; 75:2991-3008. [PMID: 29777261 PMCID: PMC11105454 DOI: 10.1007/s00018-018-2843-7] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Revised: 04/25/2018] [Accepted: 05/16/2018] [Indexed: 01/05/2023]
Abstract
Age-related macular degeneration (AMD) is the predominant cause of visual loss in old people in the developed world, whose incidence is increasing. This disease is caused by the decrease in macular function, due to the degeneration of retinal pigment epithelium (RPE) cells. The aged retina is characterised by increased levels of reactive oxygen species (ROS), impaired autophagy, and DNA damage that are linked to AMD pathogenesis. Mitophagy, a mitochondria-specific type of autophagy, is an essential part of mitochondrial quality control, the collective mechanism responsible for this organelle's homeostasis. The abundance of ROS, DNA damage, and the excessive energy consumption in the ageing retina all contribute to the degeneration of RPE cells and their mitochondria. We discuss the role of mitophagy in the cell and argue that its impairment may play a role in AMD pathogenesis. Thus, mitophagy as a potential therapeutic target in AMD and other degenerative diseases is as well explored.
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Affiliation(s)
- Juha M T Hyttinen
- Department of Ophthalmology, Institute of Clinical Medicine, University of Eastern Finland, P.O. Box 1627, 70211, Kuopio, Finland.
| | - Johanna Viiri
- Department of Ophthalmology, Institute of Clinical Medicine, University of Eastern Finland, P.O. Box 1627, 70211, Kuopio, Finland
| | - Kai Kaarniranta
- Department of Ophthalmology, Institute of Clinical Medicine, University of Eastern Finland, P.O. Box 1627, 70211, Kuopio, Finland
- Department of Ophthalmology, Kuopio University Hospital, P.O. Box 100, 70029 KYS, Kuopio, Finland
| | - Janusz Błasiak
- Department of Molecular Genetics, University of Łódź, Pomorska 141/143, 90-236, Łódź, Poland
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26
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Guo X, Jiang Q, Tuccitto A, Chan D, Alqawlaq S, Won GJ, Sivak JM. The AMPK-PGC-1α signaling axis regulates the astrocyte glutathione system to protect against oxidative and metabolic injury. Neurobiol Dis 2018; 113:59-69. [PMID: 29438738 DOI: 10.1016/j.nbd.2018.02.004] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2017] [Revised: 01/10/2018] [Accepted: 02/08/2018] [Indexed: 02/04/2023] Open
Abstract
Neurons are highly sensitive to metabolic and oxidative injury, but endogenous astrocyte mechanisms have a critical capacity to provide protection from these stresses. We previously reported that the master regulator PGC-1α (peroxisome proliferator-activated receptor gamma coactivator-1α) is necessary for retinal astrocytes to mount effective injury responses, with particular regard to oxidative stress. Yet, this pathway has not been well studied in glia. PGC-1α is a transcriptional co-activator that is dysregulated in a variety of neurodegenerative diseases. It functions as a master regulator of cellular bioenergetics, with the ability to regulate tissue specific responses. A key inducer of PGC-1α signaling is adenosine monophosphate-activated kinase (AMPK). Thus, the AMPK-PGC-1α signaling axis coordinates metabolic and oxidative damage responses in the central nervous system (CNS). Here we report that AMPK selectively regulates expression of GCLM (glutamate cysteine ligase modulatory subunit) in astrocytes, but not neurons, through PGC-1α activation. Glutamate cysteine ligase (GCL) is the rate limiting enzyme in the biosynthesis of glutathione (GSH); a critical antioxidant and detoxifying peptide in the CNS. Through this mechanism we describe PGC-1α-dependent induction of GSH synthesis and antioxidant activity in astrocytes, and in the rodent retina in vivo. Furthermore, we demonstrate that therapeutic agonism of this pathway with the AMP mimetic, AICAR, rescues GSH levels in vivo, while reducing RGC death and astrocyte reactivity, following retinal ischemia/reperfusion injury. This mechanism presents a novel strategy for enhancing protective astrocyte antioxidant capacity in the CNS.
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Affiliation(s)
- Xiaoxin Guo
- Krembil Research Institute, University Health Network, Toronto, Ontario, Canada; Department of Ophthalmology and Vision Science, University of Toronto, Toronto, Ontario, Canada
| | - Qi Jiang
- Krembil Research Institute, University Health Network, Toronto, Ontario, Canada; Department of Ophthalmology and Vision Science, University of Toronto, Toronto, Ontario, Canada; Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada
| | - Alessandra Tuccitto
- Krembil Research Institute, University Health Network, Toronto, Ontario, Canada; Department of Ophthalmology and Vision Science, University of Toronto, Toronto, Ontario, Canada; Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada
| | - Darren Chan
- Krembil Research Institute, University Health Network, Toronto, Ontario, Canada; Department of Ophthalmology and Vision Science, University of Toronto, Toronto, Ontario, Canada
| | - Samih Alqawlaq
- Krembil Research Institute, University Health Network, Toronto, Ontario, Canada; Department of Ophthalmology and Vision Science, University of Toronto, Toronto, Ontario, Canada; Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada
| | - Gah-Jone Won
- Krembil Research Institute, University Health Network, Toronto, Ontario, Canada; Department of Ophthalmology and Vision Science, University of Toronto, Toronto, Ontario, Canada
| | - Jeremy M Sivak
- Krembil Research Institute, University Health Network, Toronto, Ontario, Canada; Department of Ophthalmology and Vision Science, University of Toronto, Toronto, Ontario, Canada; Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada.
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27
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Li X, Wang H, Wen G, Li L, Gao Y, Zhuang Z, Zhou M, Mao L, Fan Y. Neuroprotection by quercetin via mitochondrial function adaptation in traumatic brain injury: PGC-1α pathway as a potential mechanism. J Cell Mol Med 2017; 22:883-891. [PMID: 29205806 PMCID: PMC5783850 DOI: 10.1111/jcmm.13313] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2016] [Accepted: 06/09/2017] [Indexed: 02/04/2023] Open
Abstract
The aim of this study was to investigate the neuroprotective effects of quercetin in mouse models of traumatic brain injury (TBI) and the potential role of the PGC‐1α pathway in putative neuroprotection. Wild‐type mice were randomly assigned to four groups: the sham group, the TBI group, the TBI+vehicle group and the TBI+quercetin group. Quercetin, a dietary flavonoid used as a food supplement, significantly reduced TBI‐induced neuronal apoptosis and ameliorated mitochondrial lesions. It significantly accelerated the translocation of PGC‐1α protein from the cytoplasm to the nucleus. In addition, quercetin restored the level of cytochrome c, malondialdehyde and superoxide dismutase in mitochondria. Therefore, quercetin administration can potentially attenuate brain injury in a TBI model by increasing the activities of mitochondrial biogenesis via the mediation of the PGC‐1α pathway.
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Affiliation(s)
- Xiang Li
- Department of Neurosurgery, Jinling Hospital, Medical School of Medicine, Nanjing University, Nanjing, Jiangsu Province, China
| | - Handong Wang
- Department of Neurosurgery, Jinling Hospital, Medical School of Medicine, Nanjing University, Nanjing, Jiangsu Province, China
| | - Guodao Wen
- Department of Neurosurgery, Jinling Hospital, Medical School of Medicine, Nanjing University, Nanjing, Jiangsu Province, China
| | - Liwen Li
- Department of Neurosurgery, Jinling Hospital, Medical School of Medicine, Nanjing University, Nanjing, Jiangsu Province, China
| | - Yongyue Gao
- Department of Neurosurgery, Jinling Hospital, Medical School of Medicine, Nanjing University, Nanjing, Jiangsu Province, China
| | - Zong Zhuang
- Department of Neurosurgery, Jinling Hospital, Medical School of Medicine, Nanjing University, Nanjing, Jiangsu Province, China
| | - Mengliang Zhou
- Department of Neurosurgery, Jinling Hospital, Medical School of Medicine, Nanjing University, Nanjing, Jiangsu Province, China
| | - Lei Mao
- Department of Neurosurgery, Jinling Hospital, Medical School of Medicine, Nanjing University, Nanjing, Jiangsu Province, China
| | - Youwu Fan
- Department of Neurosurgery, Jinling Hospital, Medical School of Medicine, Nanjing University, Nanjing, Jiangsu Province, China
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28
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Nagar S, Trudler D, McKercher SR, Piña-Crespo J, Nakanishi N, Okamoto SI, Lipton SA. Molecular Pathway to Protection From Age-Dependent Photoreceptor Degeneration in Mef2 Deficiency. Invest Ophthalmol Vis Sci 2017; 58:3741-3749. [PMID: 28738418 PMCID: PMC5525556 DOI: 10.1167/iovs.17-21767] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Purpose Photoreceptor degeneration in the retina is a major cause of blindness in humans. Elucidating mechanisms of degenerative and neuroprotective pathways in photoreceptors should afford identification and development of therapeutic strategies. Methods We used mouse genetic models and improved methods for retinal explant cultures. Retinas were enucleated from Mef2d+/+ and Mef2d−/− mice, stained for MEF2 proteins and outer nuclear layer thickness, and assayed for apoptotic cells. Chromatin immunoprecipitation (ChIP) assays revealed MEF2 binding, and RT-qPCR showed levels of transcription factors. We used AAV2 and electroporation to express genes in retinal explants and electroretinograms to assess photoreceptor functionality. Results We identify a prosurvival MEF2D-PGC1α pathway that plays a neuroprotective role in photoreceptors. We demonstrate that Mef2d−/− mouse retinas manifest decreased expression of PGC1α and increased photoreceptor cell loss, resulting in the absence of light responses. Molecular repletion of PGC1α protects Mef2d−/− photoreceptors and preserves light responsivity. Conclusions These results suggest that the MEF2-PGC1α cascade may represent a new therapeutic target for drugs designed to protect photoreceptors from developmental- and age-dependent loss.
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Affiliation(s)
- Saumya Nagar
- Neuroscience and Aging Research Center and Graduate School of Biomedical Sciences, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California, United States
| | - Dorit Trudler
- Neurodegenerative Disease Center, Scintillon Institute, San Diego, California, United States
| | - Scott R McKercher
- Neurodegenerative Disease Center, Scintillon Institute, San Diego, California, United States
| | - Juan Piña-Crespo
- Neuroscience and Aging Research Center and Graduate School of Biomedical Sciences, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California, United States
| | - Nobuki Nakanishi
- Neurodegenerative Disease Center, Scintillon Institute, San Diego, California, United States
| | - Shu-Ichi Okamoto
- Neurodegenerative Disease Center, Scintillon Institute, San Diego, California, United States
| | - Stuart A Lipton
- Neuroscience and Aging Research Center and Graduate School of Biomedical Sciences, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California, United States 2Neurodegenerative Disease Center, Scintillon Institute, San Diego, California, United States 3Department of Neurosciences, University of California, San Diego, School of Medicine, La Jolla, California, United States 4Department of Molecular Medicine, The Scripps Research Institute, La Jolla, California, United States
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29
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Golestaneh N, Chu Y, Cheng SK, Cao H, Poliakov E, Berinstein DM. Repressed SIRT1/PGC-1α pathway and mitochondrial disintegration in iPSC-derived RPE disease model of age-related macular degeneration. J Transl Med 2016; 14:344. [PMID: 27998274 PMCID: PMC5175395 DOI: 10.1186/s12967-016-1101-8] [Citation(s) in RCA: 79] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Accepted: 11/29/2016] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND Study of age related macular degeneration (AMD) has been hampered by lack of human models that represent the complexity of the disease. Here we have developed a human in vitro disease model of AMD to investigate the underlying AMD disease mechanisms. METHODS Generation of iPSCs from retinal pigment epithelium (RPE) of AMD donors, age-matched normal donors, skin fibroblasts of a dry AMD patient, and differentiation of iPSCs into RPE (AMD RPE-iPSC-RPE, normal RPE-iPSC-RPE and AMD Skin-iPSC-RPE, respectively). Immunostaining, cell viability assay and reactive oxygen species (ROS) production under oxidative stress conditions, electron microscopy (EM) imaging, ATP production and glycogen concentration assays, quantitative real time PCR, western blot, karyotyping. RESULTS The AMD RPE-iPSC-RPE and AMD Skin-iPSC-RPE present functional impairment and exhibit distinct disease phenotypes compared to RPE-iPSC-RPE generated from normal donors (Normal RPE-iPSC-RPE). The AMD RPE-iPSC-RPE and AMD Skin-iPSC-RPE show increased susceptibility to oxidative stress and produced higher levels of reactive oxygen species (ROS) under stress in accordance with recent reports. The susceptibility to oxidative stress-induced cell death in AMD RPE-iPSC-RPE and Skin-iPSC-RPE was consistent with inability of the AMD RPE-iPSC-RPE and Skin-iPSC-RPE to increase SOD2 expression under oxidative stress. Phenotypic analysis revealed disintegrated mitochondria, accumulation of autophagosomes and lipid droplets in AMD RPE-iPSC-RPE and AMD Skin-iPSC-RPE. Mitochondrial activity was significantly lower in AMD RPE-iPSC-RPE and AMD Skin-iPSC-RPE compared to normal cells and glycogen concentration was significantly increased in the diseased cells. Furthermore, Peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α), a regulator of mitochondrial biogenesis and function was repressed, and lower expression levels of NAD-dependent deacetylase sirtuin1 (SIRT1) were found in AMD RPE-iPSC-RPE and AMD Skin-iPSC-RPE as compared to normal RPE-iPSC-RPE. CONCLUSIONS Our studies suggest SIRT1/PGC-1α as underlying pathways contributing to AMD pathophysiology, and open new avenues for development of targeted drugs for treatment of this devastating neurodegenerative disease of the visual system.
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Affiliation(s)
- Nady Golestaneh
- Department of Ophthalmology, Georgetown University Medical Center, 3900 Reservoir Road NW, Medical-Dental Building, Room NE203, Washington, DC 20057 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, 3900 Reservoir Road NW, Medical-Dental Building, Room NE203, Washington, DC 20057 USA
| | - Shuk Kei Cheng
- Department of Ophthalmology, Georgetown University Medical Center, 3900 Reservoir Road NW, Medical-Dental Building, Room NE203, Washington, DC 20057 USA
| | - Hong Cao
- Department of Ophthalmology, Georgetown University Medical Center, 3900 Reservoir Road NW, Medical-Dental Building, Room NE203, Washington, DC 20057 USA
| | - Eugenia Poliakov
- Retinal Cell and Molecular Biology (LRCMB), National Eye Institute, National Institutes of Health, Bethesda, MD USA
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30
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Iacovelli J, Rowe GC, Khadka A, Diaz-Aguilar D, Spencer C, Arany Z, Saint-Geniez M. PGC-1α Induces Human RPE Oxidative Metabolism and Antioxidant Capacity. Invest Ophthalmol Vis Sci 2016; 57:1038-51. [PMID: 26962700 PMCID: PMC4788093 DOI: 10.1167/iovs.15-17758] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Purpose Oxidative stress and metabolic dysregulation of the RPE have been implicated in AMD; however, the molecular regulation of RPE metabolism remains unclear. The transcriptional coactivator, peroxisome proliferator-activated receptor-gamma coactivator 1α (PGC-1α) is a powerful mediator of mitochondrial function. This study examines the ability of PGC-1α to regulate RPE metabolic program and oxidative stress response. Methods Primary human fetal RPE (hfRPE) and ARPE-19 were matured in vitro using standard culture conditions. Mitochondrial mass of RPE was measured using MitoTracker staining and citrate synthase activity. Expression of PGC-1 isoforms, RPE-specific genes, oxidative metabolism proteins, and antioxidant enzymes was analyzed by quantitative PCR and Western blot. Mitochondrial respiration and fatty-acid oxidation were monitored using the Seahorse extracellular flux analyzer. Expression of PGC-1α was increased using adenoviral delivery. ARPE-19 were exposed to hydrogen peroxide to induce oxidative stress. Reactive oxygen species were measured by CM-H2DCFDA fluorescence. Cell death was analyzed by LDH release. Results Maturation of ARPE-19 and hfRPE was associated with significant increase in mitochondrial mass, expression of oxidative phosphorylation (OXPHOS) genes, and PGC-1α gene expression. Overexpression of PGC-1α increased expression of OXPHOS and fatty-acid β-oxidation genes, ultimately leading to the potent induction of mitochondrial respiration and fatty-acid oxidation. PGC-1α gain of function also strongly induced numerous antioxidant genes and, importantly, protected RPE from oxidant-mediated cell death without altering RPE functions. Conclusions This study provides important insights into the metabolic changes associated with RPE functional maturation and identifies PGC-1α as a potent driver of RPE mitochondrial function and antioxidant capacity.
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Affiliation(s)
- Jared Iacovelli
- Schepens Eye Research Institute, Massachusetts Eye and Ear Infirmary, Boston, Massachusetts, United States 2Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts, United States
| | - Glenn C Rowe
- Division of Cardiovascular Disease, University of Alabama at Birmingham, Birmingham, Alabama, United States
| | - Arogya Khadka
- Schepens Eye Research Institute, Massachusetts Eye and Ear Infirmary, Boston, Massachusetts, United States
| | - Daniel Diaz-Aguilar
- Angiogenesis Laboratory, Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, Boston, Massachusetts, United States
| | - Carrie Spencer
- Schepens Eye Research Institute, Massachusetts Eye and Ear Infirmary, Boston, Massachusetts, United States
| | - Zoltan Arany
- Cardiovascular Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Magali Saint-Geniez
- Schepens Eye Research Institute, Massachusetts Eye and Ear Infirmary, Boston, Massachusetts, United States 2Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts, United States
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Gill JF, Delezie J, Santos G, Handschin C. PGC-1α expression in murine AgRP neurons regulates food intake and energy balance. Mol Metab 2016; 5:580-588. [PMID: 27408781 PMCID: PMC4921790 DOI: 10.1016/j.molmet.2016.05.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Revised: 05/10/2016] [Accepted: 05/12/2016] [Indexed: 01/04/2023] Open
Abstract
Objective Food intake and whole-body energy homeostasis are controlled by agouti-related protein (AgRP) and pro-opiomelanocortin (POMC) neurons located in the arcuate nucleus of the hypothalamus. Key energy sensors, such as the AMP-activated protein kinase (AMPK) or sirtuin 1 (SIRT1), are essential in AgRP and POMC cells to ensure proper energy balance. In peripheral tissues, the transcriptional coactivator PGC-1α closely associates with these sensors to regulate cellular metabolism. The role of PGC-1α in the ARC nucleus, however, remains unknown. Methods Using AgRP and POMC neurons specific knockout (KO) mouse models we studied the consequences of PGC-1α deletion on metabolic parameters during fed and fasted states and on ghrelin and leptin responses. We also took advantage of an immortalized AgRP cell line to assess the impact of PGC-1α modulation on fasting induced AgRP expression. Results PGC-1α is dispensable for POMC functions in both fed and fasted states. In stark contrast, mice carrying a specific deletion of PGC-1α in AgRP neurons display increased adiposity concomitant with significantly lower body temperature and RER values during nighttime. In addition, the absence of PGC-1α in AgRP neurons reduces food intake in the fed and fasted states and alters the response to leptin. Finally, both in vivo and in an immortalized AgRP cell line, PGC-1α modulates AgRP expression induction upon fasting. Conclusions Collectively, our results highlight a role for PGC-1α in the regulation of AgRP neuronal functions in the control of food intake and peripheral metabolism. The AgRP induction upon fasting is modulated by PGC-1α. PGC-1α is important for the response of AgRP neurons to fasting and leptin. Deletion of PGC-1α in AgRP neurons impairs whole body energy balance. PGC-1α deletion in POMC neurons is dispensable for energy homeostasis regulation.
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Affiliation(s)
- Jonathan F Gill
- Biozentrum, University of Basel, Klingelbergstrasse 50/70, CH-4056 Basel, Switzerland.
| | - Julien Delezie
- Biozentrum, University of Basel, Klingelbergstrasse 50/70, CH-4056 Basel, Switzerland.
| | - Gesa Santos
- Biozentrum, University of Basel, Klingelbergstrasse 50/70, CH-4056 Basel, Switzerland.
| | - Christoph Handschin
- Biozentrum, University of Basel, Klingelbergstrasse 50/70, CH-4056 Basel, Switzerland.
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Kunst S, Wolloscheck T, Kelleher DK, Wolfrum U, Sargsyan SA, Iuvone PM, Baba K, Tosini G, Spessert R. Pgc-1α and Nr4a1 Are Target Genes of Circadian Melatonin and Dopamine Release in Murine Retina. Invest Ophthalmol Vis Sci 2016; 56:6084-94. [PMID: 26393668 DOI: 10.1167/iovs.15-17503] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
PURPOSE The neurohormones melatonin and dopamine mediate clock-dependent/circadian regulation of inner retinal neurons and photoreceptor cells and in this way promote their functional adaptation to time of day and their survival. To fulfill this function they act on melatonin receptor type 1 (MT1 receptors) and dopamine D4 receptors (D4 receptors), respectively. The aim of the present study was to screen transcriptional regulators important for retinal physiology and/or pathology (Dbp, Egr-1, Fos, Nr1d1, Nr2e3, Nr4a1, Pgc-1α, Rorβ) for circadian regulation and dependence on melatonin signaling/MT1 receptors or dopamine signaling/D4 receptors. METHODS This was done by gene profiling using quantitative polymerase chain reaction in mice deficient in MT1 or D4 receptors. RESULTS The data obtained determined Pgc-1α and Nr4a1 as transcriptional targets of circadian melatonin and dopamine signaling, respectively. CONCLUSIONS The results suggest that Pgc-1α and Nr4a1 represent candidate genes for linking circadian neurohormone release with functional adaptation and healthiness of retina and photoreceptor cells.
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Affiliation(s)
- Stefanie Kunst
- Institute of Functional and Clinical Anatomy University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany 2Department of Cell and Matrix Biology, Institute of Zoology, Johannes Gutenberg University, Mainz, Germany
| | - Tanja Wolloscheck
- Institute of Functional and Clinical Anatomy University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Debra K Kelleher
- Institute of Functional and Clinical Anatomy University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Uwe Wolfrum
- Department of Cell and Matrix Biology, Institute of Zoology, Johannes Gutenberg University, Mainz, Germany
| | - S Anna Sargsyan
- Departments of Ophthalmology and Pharmacology, Emory University School of Medicine, Atlanta, Georgia, United States
| | - P Michael Iuvone
- Departments of Ophthalmology and Pharmacology, Emory University School of Medicine, Atlanta, Georgia, United States
| | - Kenkichi Baba
- Neuroscience Institute and Department of Pharmacology and Toxicology, Morehouse School of Medicine, Atlanta, Georgia, United States
| | - Gianluca Tosini
- Neuroscience Institute and Department of Pharmacology and Toxicology, Morehouse School of Medicine, Atlanta, Georgia, United States
| | - Rainer Spessert
- Institute of Functional and Clinical Anatomy University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
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The Role of AMPK Pathway in Neuroprotection. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 854:425-30. [DOI: 10.1007/978-3-319-17121-0_56] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
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Abrahan C, Ash JD. The Potential Use of PGC-1α and PGC-1β to Protect the Retina by Stimulating Mitochondrial Repair. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 854:403-9. [PMID: 26427438 DOI: 10.1007/978-3-319-17121-0_53] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Damage to mitochondria is a common mechanism of cell death in inherited neurodegenerative disorders. Therefore, mitochondrial protection and mitochondrial repair are promising strategies to induce retinal neuroprotection. Peroxisome proliferator-activated receptor γ coactivator-α (PGC-1α) and β (PGC-1β) are transcriptional coactivators that are the main regulators of mitochondrial biogenesis. We propose that PGC-1α and PGC-1β could play a role in regulating retina cell survival, and may be important therapeutic targets to prevent retinal degeneration.
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Affiliation(s)
- Carolina Abrahan
- Department of Environmental Horticulture Research, University of Florida, Gainesville, FL 32611-0670, USA.
| | - John D Ash
- Department of Ophthalmology, University of Florida, ARB-RG232, 1600 SW Archer Rd, 32610, Gainesville, FL, USA.
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Roggia MF, Ueta T. αvβ5 Integrin/FAK/PGC-1α Pathway Confers Protective Effects on Retinal Pigment Epithelium. PLoS One 2015; 10:e0134870. [PMID: 26244551 PMCID: PMC4526642 DOI: 10.1371/journal.pone.0134870] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2015] [Accepted: 07/14/2015] [Indexed: 12/21/2022] Open
Abstract
Purpose To elucidate the mechanism of the induction of peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α) by photoreceptor outer segments (POS) and its effects on retinal pigment epithelium (RPE). Methods PGC-1α upregulation by POS was confirmed in ARPE-19 cells and in RPE ex vivo. To elucidate the mechanism, siRNAs against β5 integrin, CD36, Mer tyrosine kinase (MerTK), and Atg5, blocking antibodies against CD36 and MerTK, and a specific inhibitor for focal adhesion kinase (FAK) were used. We examined the effect of POS-induced PGC-1α upregulation on the levels of reactive oxygen species (ROS), mitochondrial biogenesis, senescence-associated β-galactosidase (SA-β-gal) after H2O2 treatment, and lysosomal activity. Lysosomal activity was evaluated through transcriptional factor EB and its target genes, and the activity of cathepsin D. Lipid metabolism after POS treatment was assessed using Oil Red O and BODIPY C11. RPE phenotypes of PGC-1α-deficient mice were examined. Results POS-induced PGC-1α upregulation was suppressed by siRNA against β5 integrin and a FAK inhibitor. siRNAs and blocking antibodies against CD36 and MerTK enhanced the effect of POS on PGC-1α. The upregulation of PGC-1α increased the levels of mRNA for antioxidant enzymes and stimulated mitochondrial biogenesis, decreased ROS levels, and reduced SA-β-gal staining in H2O2-treated ARPE-19 cells. PGC-1α was critical for lysosomal activity and lipid metabolism after POS treatment. PGC-1α-deficient mice demonstrated an accumulation of type 2 lysosomes in RPE, thickening of Bruch’s membrane, and poor choriocapillaris vasculature. Conclusions The binding, but not the internalization of POS confers protective effects on RPE cells through the αvβ5 integrin/FAK/PGC-1α pathway.
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Affiliation(s)
- Murilo F. Roggia
- Department of Ophthalmology, Graduate School of Medicine and Faculty of Medicine, The University of Tokyo, Tokyo, Japan
| | - Takashi Ueta
- Department of Ophthalmology, Graduate School of Medicine and Faculty of Medicine, The University of Tokyo, Tokyo, Japan
- * E-mail:
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Dai Y, Zhao C, Liang X, Dai R, Dong F. Protectin DX, a double lipoxygenase product from DHA, inhibits the production of both inflammatory cytokines and reactive oxygen species in human retinal pigment epithelium cells. EUR J LIPID SCI TECH 2015. [DOI: 10.1002/ejlt.201400423] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Yining Dai
- Department of Ophthalmology; Peking Union Medical College Hospital; Peking Union Medical College and Chinese Academy of Medical Sciences; Beijing China
| | - Chan Zhao
- Department of Ophthalmology; Peking Union Medical College Hospital; Peking Union Medical College and Chinese Academy of Medical Sciences; Beijing China
| | - Xiaofang Liang
- Department of Ophthalmology; Peking Union Medical College Hospital; Peking Union Medical College and Chinese Academy of Medical Sciences; Beijing China
| | - Rongping Dai
- Department of Ophthalmology; Peking Union Medical College Hospital; Peking Union Medical College and Chinese Academy of Medical Sciences; Beijing China
| | - Fangtian Dong
- Department of Ophthalmology; Peking Union Medical College Hospital; Peking Union Medical College and Chinese Academy of Medical Sciences; Beijing China
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Kunst S, Wolloscheck T, Grether M, Trunsch P, Wolfrum U, Spessert R. Photoreceptor cells display a daily rhythm in the orphan receptor Esrrβ. Mol Vis 2015; 21:173-84. [PMID: 25737630 PMCID: PMC4337357] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2014] [Accepted: 02/17/2015] [Indexed: 11/23/2022] Open
Abstract
PURPOSE Nuclear orphan receptors are critical for the development and long-term survival of photoreceptor cells. In the present study, the expression of the nuclear orphan receptor Esrrβ--a transcriptional regulator of energy metabolism that protects rod photoreceptors from dystrophy--was tested under daily regulation in the retina and photoreceptor cells. METHODS The daily transcript and protein amount profiles were recorded in preparations of the whole retina and microdissected photoreceptor cells using quantitative PCR (qPCR) and western blot analysis. RESULTS Esrrβ displayed a daily rhythm with elevated values at night in the whole retina and enriched photoreceptor cells. Daily regulation of Esrrβ mRNA depended on light input but not on melatonin, and evoked a corresponding rhythm in the Esrrβ protein. CONCLUSIONS The data presented in this study indicate that daily regulation of Esrrβ in photoreceptor cells may contribute to their adaptation to 24-h changes in metabolic demands.
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Affiliation(s)
- Stefanie Kunst
- Institute of Functional and Clinical Anatomy, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany,Department of Cell and Matrix Biology, Institute of Zoology, Johannes Gutenberg University Mainz, Mainz, Germany
| | - Tanja Wolloscheck
- Institute of Functional and Clinical Anatomy, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Markus Grether
- Institute of Functional and Clinical Anatomy, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Patricia Trunsch
- Institute of Functional and Clinical Anatomy, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Uwe Wolfrum
- Department of Cell and Matrix Biology, Institute of Zoology, Johannes Gutenberg University Mainz, Mainz, Germany
| | - Rainer Spessert
- Institute of Functional and Clinical Anatomy, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
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Villena JA. New insights into PGC-1 coactivators: redefining their role in the regulation of mitochondrial function and beyond. FEBS J 2015; 282:647-72. [DOI: 10.1111/febs.13175] [Citation(s) in RCA: 252] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2014] [Revised: 10/31/2014] [Accepted: 12/10/2014] [Indexed: 12/25/2022]
Affiliation(s)
- Josep A. Villena
- Laboratory of Metabolism and Obesity; Vall d'Hebron-Institut de Recerca; Universitat Autònoma de Barcelona; Spain
- CIBERDEM (CIBER de Diabetes y Enfermedades Metabólicas Asociadas); Instituto de Salud Carlos III; Barcelona Spain
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PGC-1α signaling coordinates susceptibility to metabolic and oxidative injury in the inner retina. THE AMERICAN JOURNAL OF PATHOLOGY 2014; 184:1017-1029. [PMID: 24508229 DOI: 10.1016/j.ajpath.2013.12.012] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 06/05/2013] [Revised: 11/29/2013] [Accepted: 12/05/2013] [Indexed: 02/06/2023]
Abstract
Retinal ganglion cells (RGCs), used as a common model of central nervous system injury, are particularly vulnerable to metabolic and oxidative damage. However, molecular mechanisms underlying this sensitivity have not been determined in vivo. PGC-1α (encoded by PPARGC1A) regulates adaptive metabolism and oxidative stress responses in a tissue- and cell-specific manner. Aberrant PGC-1α signaling is implicated in neurodegeneration, but the mechanism underlying its role in central nervous system injury remains unclear. We provide evidence from a mouse model that PGC-1α expression and activity are induced in adult retina in response to metabolic and oxidative challenge. Deletion of Ppargc1a dramatically increased RGC loss, in association with dysregulated expression of PGC-1α target metabolic and oxidative stress response genes, including Hmox1 (encoding HO-1), Tfam, and Vegfa. Vehicle-treated and naive Ppargc1a(-/-) mice also showed mild RGC loss, and surprisingly prominent and consistent retinal astrocyte reactivity. These cells critically regulate metabolic homeostasis in the inner retina. We show that PGC-1α signaling (not previously studied in glia) regulates detoxifying astrocyte responses to hypoxic and oxidative stresses. Finally, PGC-1α expression was modulated in the inner retina with age and in a model of chronic optic neuropathy. These data implicate PGC-1α signaling as an important regulator of astrocyte reactivity and RGC homeostasis to coordinate pathogenic susceptibility to metabolic and oxidative injury in the inner retina.
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Functional crosstalk of PGC-1 coactivators and inflammation in skeletal muscle pathophysiology. Semin Immunopathol 2013; 36:27-53. [DOI: 10.1007/s00281-013-0406-4] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2013] [Accepted: 10/29/2013] [Indexed: 02/06/2023]
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Kunst S, Wolloscheck T, Hölter P, Wengert A, Grether M, Sticht C, Weyer V, Wolfrum U, Spessert R. Transcriptional analysis of rat photoreceptor cells reveals daily regulation of genes important for visual signaling and light damage susceptibility. J Neurochem 2013; 124:757-69. [PMID: 23145934 DOI: 10.1111/jnc.12089] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2012] [Revised: 11/02/2012] [Accepted: 11/07/2012] [Indexed: 01/20/2023]
Abstract
Photoreceptor cells face the challenge of adjusting their function and, possibly, their susceptibility to light damage to the marked daily changes in ambient light intensity. To achieve a better understanding of photoreceptor adaptation at the transcriptional level, this study aimed to identify genes which are under daily regulation in photoreceptor cells using microarray analysis and quantitative PCR. Included in the gene set obtained were a number of genes which up until now have not been shown to be expressed in photoreceptor cells, such as Atf3 (activating transcription factor 3) and Pde8a (phosphodiesterase 8A), and others with a known impact on phototransduction and/or photoreceptor survival, such as Grk1 (G protein-coupled receptor kinase 1) and Pgc-1α (peroxisome proliferator-activated receptor γ, coactivator 1alpha). According to their daily dynamics, the genes identified could be clustered in two groups: those with peak expression during the second part of the day which are uniformly promoted to cycle by light/dark transitions and those with peak expression during the second part of the night which are predominantly driven by a clock. Since Grk1 and Pgc-1α belong in the first group, the present results support a concept in which transcriptional regulation of genes by ambient light contributes to the functional adjustment of photoreceptor cells over the 24-h period.
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Affiliation(s)
- Stefanie Kunst
- Institute of Functional and Clinical Anatomy, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany.
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Saint-Geniez M, Jiang A, Abend S, Liu L, Sweigard H, Connor KM, Arany Z. PGC-1α regulates normal and pathological angiogenesis in the retina. THE AMERICAN JOURNAL OF PATHOLOGY 2012; 182:255-65. [PMID: 23141926 DOI: 10.1016/j.ajpath.2012.09.003] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2012] [Revised: 08/29/2012] [Accepted: 09/04/2012] [Indexed: 11/26/2022]
Abstract
Neovascular diseases of the eye are the most common causes of blindness worldwide. The mechanisms underlying pathological neovascularization in the retina remain incompletely understood. PGC-1α is a transcriptional coactivator that plays a central role in the regulation of cellular metabolism. In skeletal muscle, PGC-1α induces VEGFA expression and powerfully promotes angiogenesis, suggesting a similar role in other tissues. This study investigates the role of PGC-1α during normal and pathological vascularization in the retina. We show that PGC-1α induces the expression of VEGFA in numerous retinal cells, and that PGC-1α expression is strongly induced during postnatal retinal development, coincident with VEGFA expression and angiogenesis. PGC-1α(-/-) mice have a significant reduction of early retinal vascular outgrowth, and reduced density of capillaries and number of main arteries and veins as adults. In the oxygen-induced retinopathy model of retinopathy of prematurity, PGC-1α expression is dramatically induced in the inner nuclear layer of the retina, suggesting that PGC-1α drives pathological neovascularization. In support of this, PGC-1α(-/-) mice subjected to oxygen-induced retinopathy had decreased expression of VEGFA and were protected against pathological neovascularization. These results demonstrate that PGC-1α regulates VEGFA in the retina and is required for normal vessel development and for pathological neovascularization. The data highlight PGC-1α as a novel target in the treatment of neovascular diseases of the eye.
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Affiliation(s)
- Magali Saint-Geniez
- Schepens Eye Research Institute, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, USA
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