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Al-Bassam L, Shearman GC, Brocchini S, Alany RG, Williams GR. The Potential of Selenium-Based Therapies for Ocular Oxidative Stress. Pharmaceutics 2024; 16:631. [PMID: 38794293 PMCID: PMC11125443 DOI: 10.3390/pharmaceutics16050631] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2024] [Revised: 04/26/2024] [Accepted: 05/01/2024] [Indexed: 05/26/2024] Open
Abstract
Oxidative stress plays a critical role in the development of chronic ocular conditions including cataracts, age-related macular degeneration, and diabetic retinopathy. There is a need to explore the potential of topical antioxidants to slow the progression of those conditions by mediating oxidative stress and maintaining ocular health. Selenium has attracted considerable attention because it is a component of selenoproteins and antioxidant enzymes. The application of selenium to a patient can increase selenoprotein expression, counteracting the effect of reactive oxygen species by increasing the presence of antioxidant enzymes, and thus slowing the progression of chronic ocular disorders. Oxidative stress effects at the biomolecular level for prevalent ocular conditions are described in this review along with some of the known defensive mechanisms, with a focus on selenoproteins. The importance of selenium in the eye is described, along with a discussion of selenium studies and uses. Selenium's antioxidant and anti-inflammatory qualities may prevent or delay eye diseases. Recent breakthroughs in drug delivery methods and nanotechnology for selenium-based ocular medication delivery are enumerated. Different types of selenium may be employed in formulations aimed at managing ocular oxidative stress conditions.
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Affiliation(s)
- Lulwah Al-Bassam
- UCL School of Pharmacy, University College London, 29-39 Brunswick Square, London WC1N 1AX, UK; (L.A.-B.); (S.B.)
| | - Gemma C. Shearman
- School of Life Sciences, Pharmacy and Chemistry, Kingston University London, Penrhyn Rd, Kingston upon Thames KT1 2EE, UK; (G.C.S.); (R.G.A.)
| | - Steve Brocchini
- UCL School of Pharmacy, University College London, 29-39 Brunswick Square, London WC1N 1AX, UK; (L.A.-B.); (S.B.)
| | - Raid G. Alany
- School of Life Sciences, Pharmacy and Chemistry, Kingston University London, Penrhyn Rd, Kingston upon Thames KT1 2EE, UK; (G.C.S.); (R.G.A.)
- School of Pharmacy, The University of Auckland, Auckland 1142, New Zealand
| | - Gareth R. Williams
- UCL School of Pharmacy, University College London, 29-39 Brunswick Square, London WC1N 1AX, UK; (L.A.-B.); (S.B.)
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2
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Brito M, Sorbier C, Mignet N, Boudy V, Borchard G, Vacher G. Understanding the Impact of Polyunsaturated Fatty Acids on Age-Related Macular Degeneration: A Review. Int J Mol Sci 2024; 25:4099. [PMID: 38612907 PMCID: PMC11012607 DOI: 10.3390/ijms25074099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2024] [Revised: 04/01/2024] [Accepted: 04/03/2024] [Indexed: 04/14/2024] Open
Abstract
Age-related Macular Degeneration (AMD) is a multifactorial ocular pathology that destroys the photoreceptors of the macula. Two forms are distinguished, dry and wet AMD, with different pathophysiological mechanisms. Although treatments were shown to be effective in wet AMD, they remain a heavy burden for patients and caregivers, resulting in a lack of patient compliance. For dry AMD, no real effective treatment is available in Europe. It is, therefore, essential to look for new approaches. Recently, the use of long-chain and very long-chain polyunsaturated fatty acids was identified as an interesting new therapeutic alternative. Indeed, the levels of these fatty acids, core components of photoreceptors, are significantly decreased in AMD patients. To better understand this pathology and to evaluate the efficacy of various molecules, in vitro and in vivo models reproducing the mechanisms of both types of AMD were developed. This article reviews the anatomy and the physiological aging of the retina and summarizes the clinical aspects, pathophysiological mechanisms of AMD and potential treatment strategies. In vitro and in vivo models of AMD are also presented. Finally, this manuscript focuses on the application of omega-3 fatty acids for the prevention and treatment of both types of AMD.
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Affiliation(s)
- Maëlis Brito
- Unither Développement Bordeaux, Avenue Toussaint Catros, 33185 Le Haillan, France
- Université Paris Cité, CNRS, INSERM, UTCBS, Unité de Technologies Chimiques et Biologiques pour la Santé, F-75006 Paris, France
- Département de Recherche et Développement (DRDP), Agence Générale des Equipements et Produits de Santé (AGEPS), Assistance Publique Hôpitaux de Paris (AP-HP), 7 Rue du Fer-à-Moulin, 75005 Paris, France
- Institute of Pharmaceutical Sciences of Western Switzerland (ISPSO), School of Pharmaceutical Sciences, University of Geneva, Rue Michel-Servet 1, 1206 Geneva, Switzerland
| | - Capucine Sorbier
- Unither Développement Bordeaux, Avenue Toussaint Catros, 33185 Le Haillan, France
| | - Nathalie Mignet
- Université Paris Cité, CNRS, INSERM, UTCBS, Unité de Technologies Chimiques et Biologiques pour la Santé, F-75006 Paris, France
| | - Vincent Boudy
- Université Paris Cité, CNRS, INSERM, UTCBS, Unité de Technologies Chimiques et Biologiques pour la Santé, F-75006 Paris, France
- Département de Recherche et Développement (DRDP), Agence Générale des Equipements et Produits de Santé (AGEPS), Assistance Publique Hôpitaux de Paris (AP-HP), 7 Rue du Fer-à-Moulin, 75005 Paris, France
| | - Gerrit Borchard
- Institute of Pharmaceutical Sciences of Western Switzerland (ISPSO), School of Pharmaceutical Sciences, University of Geneva, Rue Michel-Servet 1, 1206 Geneva, Switzerland
| | - Gaëlle Vacher
- Institute of Pharmaceutical Sciences of Western Switzerland (ISPSO), School of Pharmaceutical Sciences, University of Geneva, Rue Michel-Servet 1, 1206 Geneva, Switzerland
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3
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Rocha GS, Freire MAM, Paiva KM, Oliveira RF, Morais PLAG, Santos JR, Cavalcanti JRLP. The neurobiological effects of senescence on dopaminergic system: A comprehensive review. J Chem Neuroanat 2024; 137:102415. [PMID: 38521203 DOI: 10.1016/j.jchemneu.2024.102415] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2023] [Revised: 02/26/2024] [Accepted: 03/15/2024] [Indexed: 03/25/2024]
Abstract
Over time, the body undergoes a natural, multifactorial, and ongoing process named senescence, which induces changes at the molecular, cellular, and micro-anatomical levels in many body systems. The brain, being a highly complex organ, is particularly affected by this process, potentially impairing its numerous functions. The brain relies on chemical messengers known as neurotransmitters to function properly, with dopamine being one of the most crucial. This catecholamine is responsible for a broad range of critical roles in the central nervous system, including movement, learning, cognition, motivation, emotion, reward, hormonal release, memory consolidation, visual performance, sexual drive, modulation of circadian rhythms, and brain development. In the present review, we thoroughly examine the impact of senescence on the dopaminergic system, with a primary focus on the classic delimitations of the dopaminergic nuclei from A8 to A17. We provide in-depth information about their anatomy and function, particularly addressing how senescence affects each of these nuclei.
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Affiliation(s)
- Gabriel S Rocha
- Behavioral and Evolutionary Neurobiology Laboratory, Federal University of Sergipe (UFS), Itabaiana, Brazil
| | - Marco Aurelio M Freire
- Behavioral and Evolutionary Neurobiology Laboratory, Federal University of Sergipe (UFS), Itabaiana, Brazil
| | - Karina M Paiva
- Laboratory of Experimental Neurology, State University of Rio Grande do Norte (UERN), Mossoró, Brazil
| | - Rodrigo F Oliveira
- Laboratory of Experimental Neurology, State University of Rio Grande do Norte (UERN), Mossoró, Brazil
| | - Paulo Leonardo A G Morais
- Laboratory of Experimental Neurology, State University of Rio Grande do Norte (UERN), Mossoró, Brazil
| | - José Ronaldo Santos
- Behavioral and Evolutionary Neurobiology Laboratory, Federal University of Sergipe (UFS), Itabaiana, Brazil
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4
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Porcino C, Mhalhel K, Briglia M, Cometa M, Guerrera MC, Germanà PG, Montalbano G, Levanti M, Laurà R, Abbate F, Germanà A, Aragona M. Neurotrophins and Trk Neurotrophin Receptors in the Retina of Adult Killifish ( Nothobranchius guentheri). Int J Mol Sci 2024; 25:2732. [PMID: 38473977 DOI: 10.3390/ijms25052732] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2024] [Revised: 02/19/2024] [Accepted: 02/23/2024] [Indexed: 03/14/2024] Open
Abstract
Specific subpopulations of neurons in nerve and sensory systems must be developed and maintained, and this is accomplished in significant part by neurotrophins (NTs) and the signaling receptors on which they act, called tyrosine protein kinase receptors (Trks). The neurotrophins-tyrosine protein kinase receptors (NTs/Trks) system is involved in sensory organ regulation, including the visual system. An NTs/Trks system alteration is associated with neurodegeneration related to aging and diseases, including retinal pathologies. An emergent model in the field of translational medicine, for instance, in aging study, is the annual killifish belonging to the Nothobranchius genus, thanks to its short lifespan. Members of this genus, such as Nothobranchius guentheri, and humans share a similar retinal stratigraphy. Nevertheless, according to the authors' knowledge, the occurrence and distribution of the NTs/Trks system in the retina of N. guentheri has never been investigated before. Therefore, the present study aimed to localize neurotrophin BDNF, NGF, and NT-3 and TrkA, TrkB, and TrkC receptors in the N. guentheri retina using the immunofluorescence method. The present investigation demonstrates, for the first time, the occurrence of the NTs/Trks system in N. guentheri retina and, consequently, the potential key role of these proteins in the biology and survival of the retinal cells.
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Affiliation(s)
- Caterina Porcino
- Zebrafish Neuromorphology Lab, Department of Veterinary Sciences, University of Messina, 98168 Messina, Italy
| | - Kamel Mhalhel
- Zebrafish Neuromorphology Lab, Department of Veterinary Sciences, University of Messina, 98168 Messina, Italy
| | - Marilena Briglia
- Zebrafish Neuromorphology Lab, Department of Veterinary Sciences, University of Messina, 98168 Messina, Italy
| | - Marzio Cometa
- Zebrafish Neuromorphology Lab, Department of Veterinary Sciences, University of Messina, 98168 Messina, Italy
| | - Maria Cristina Guerrera
- Zebrafish Neuromorphology Lab, Department of Veterinary Sciences, University of Messina, 98168 Messina, Italy
| | - Patrizia Germana Germanà
- Zebrafish Neuromorphology Lab, Department of Veterinary Sciences, University of Messina, 98168 Messina, Italy
| | - Giuseppe Montalbano
- Zebrafish Neuromorphology Lab, Department of Veterinary Sciences, University of Messina, 98168 Messina, Italy
| | - Maria Levanti
- Zebrafish Neuromorphology Lab, Department of Veterinary Sciences, University of Messina, 98168 Messina, Italy
| | - Rosaria Laurà
- Zebrafish Neuromorphology Lab, Department of Veterinary Sciences, University of Messina, 98168 Messina, Italy
| | - Francesco Abbate
- Zebrafish Neuromorphology Lab, Department of Veterinary Sciences, University of Messina, 98168 Messina, Italy
| | - Antonino Germanà
- Zebrafish Neuromorphology Lab, Department of Veterinary Sciences, University of Messina, 98168 Messina, Italy
| | - Marialuisa Aragona
- Zebrafish Neuromorphology Lab, Department of Veterinary Sciences, University of Messina, 98168 Messina, Italy
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5
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Kovács-Valasek A, Rák T, Pöstyéni E, Csutak A, Gábriel R. Three Major Causes of Metabolic Retinal Degenerations and Three Ways to Avoid Them. Int J Mol Sci 2023; 24:ijms24108728. [PMID: 37240082 DOI: 10.3390/ijms24108728] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Revised: 05/10/2023] [Accepted: 05/11/2023] [Indexed: 05/28/2023] Open
Abstract
An imbalance of homeostasis in the retina leads to neuron loss and this eventually results in a deterioration of vision. If the stress threshold is exceeded, different protective/survival mechanisms are activated. Numerous key molecular actors contribute to prevalent metabolically induced retinal diseases-the three major challenges are age-related alterations, diabetic retinopathy and glaucoma. These diseases have complex dysregulation of glucose-, lipid-, amino acid or purine metabolism. In this review, we summarize current knowledge on possible ways of preventing or circumventing retinal degeneration by available methods. We intend to provide a unified background, common prevention and treatment rationale for these disorders and identify the mechanisms through which these actions protect the retina. We suggest a role for herbal medicines, internal neuroprotective substances and synthetic drugs targeting four processes: parainflammation and/or glial cell activation, ischemia and related reactive oxygen species and vascular endothelial growth factor accumulation, apoptosis and/or autophagy of nerve cells and an elevation of ocular perfusion pressure and/or intraocular pressure. We conclude that in order to achieve substantial preventive or therapeutic effects, at least two of the mentioned pathways should be targeted synergistically. A repositioning of some drugs is considered to use them for the cure of the other related conditions.
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Affiliation(s)
- Andrea Kovács-Valasek
- Department of Experimental Zoology and Neurobiology, University of Pécs, Ifjúság útja 6, 7624 Pécs, Hungary
| | - Tibor Rák
- Department of Ophthalmology, Medical School, University of Pécs, Szigeti út 12, 7624 Pécs, Hungary
| | - Etelka Pöstyéni
- Department of Experimental Zoology and Neurobiology, University of Pécs, Ifjúság útja 6, 7624 Pécs, Hungary
| | - Adrienne Csutak
- Department of Ophthalmology, Medical School, University of Pécs, Szigeti út 12, 7624 Pécs, Hungary
| | - Robert Gábriel
- Department of Experimental Zoology and Neurobiology, University of Pécs, Ifjúság útja 6, 7624 Pécs, Hungary
- János Szentágothai Research Centre, University of Pécs, Ifjúság útja 20, 7624 Pécs, Hungary
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6
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Goodman D, Ness S. The Role of Oxidative Stress in the Aging Eye. Life (Basel) 2023; 13:life13030837. [PMID: 36983992 PMCID: PMC10052045 DOI: 10.3390/life13030837] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Revised: 03/13/2023] [Accepted: 03/14/2023] [Indexed: 03/30/2023] Open
Abstract
Given the expanding elderly population in the United States and the world, it is important to understand the processes underlying both natural and pathological age-related changes in the eye. Both the anterior and posterior segment of the eye undergo changes in biological, chemical, and physical properties driven by oxidative stress. With advancing age, changes in the anterior segment include dermatochalasis, blepharoptosis, thickening of the sclera, loss of corneal endothelial cells, and stiffening of the lens. Changes in the posterior segment include lowered viscoelasticity of the vitreous body, photoreceptor cell loss, and drusen deposition at the macula and fovea. Age-related ocular pathologies including glaucoma, cataracts, and age-related macular degeneration are largely mediated by oxidative stress. The prevalence of these diseases is expected to increase in the coming years, highlighting the need to develop new therapies that address oxidative stress and slow the progression of age-related pathologies.
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Affiliation(s)
- Deniz Goodman
- Boston University Chobanian & Avedisian School of Medicine, Boston, MA 02118, USA
| | - Steven Ness
- Department of Ophthalmology, Boston Medical Center, Boston, MA 02118, USA
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7
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Huang L, Li R, Ye L, Zhang S, Tian H, Du M, Qu C, Li S, Li J, Yang M, Wu B, Chen R, Huang G, Zhong L, Yang H, Yu M, Shi Y, Wang C, Zhang H, Chen W, Yang Z. Deep Sc-RNA sequencing decoding the molecular dynamic architecture of the human retina. SCIENCE CHINA. LIFE SCIENCES 2023; 66:496-515. [PMID: 36115892 DOI: 10.1007/s11427-021-2163-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2021] [Accepted: 07/13/2022] [Indexed: 10/14/2022]
Abstract
The human retina serves as a light detector and signals transmission tissue. Advanced insights into retinal disease mechanisms and therapeutic strategies require a deep understanding of healthy retina molecular events. Here, we sequenced the mRNA of over 0.6 million single cells from human retinas across six regions at nine different ages. Sixty cell sub-types have been identified from the human mature retinas with unique markers. We revealed regional and age differences of gene expression profiles within the human retina. Cell-cell interaction analysis indicated a rich synaptic connection within the retinal cells. Gene expression regulon analysis revealed the specific expression of transcription factors and their regulated genes in human retina cell types. Some of the gene's expression, such as DKK3, are elevated in aged retinas. A further functional investigation suggested that over expression of DKK3 could impact mitochondrial stability. Overall, decoding the molecular dynamic architecture of the human retina improves our understanding of the vision system.
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Affiliation(s)
- Lulin Huang
- The Key Laboratory for Human Disease Gene Study of Sichuan Province and the Department of Laboratory Medicine, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, 610075, China
- Research Unit for Blindness Prevention of Chinese Academy of Medical Sciences (2019RU026), Sichuan Academy of Medical Sciences, Chengdu, 610075, China
| | - Runze Li
- The Key Laboratory for Human Disease Gene Study of Sichuan Province and the Department of Laboratory Medicine, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, 610075, China
| | - Lin Ye
- The Key Laboratory for Human Disease Gene Study of Sichuan Province and the Department of Laboratory Medicine, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, 610075, China
| | - Shanshan Zhang
- The Key Laboratory for Human Disease Gene Study of Sichuan Province and the Department of Laboratory Medicine, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, 610075, China
| | - Huaping Tian
- The Key Laboratory for Human Disease Gene Study of Sichuan Province and the Department of Laboratory Medicine, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, 610075, China
| | - Mingyan Du
- The Key Laboratory for Human Disease Gene Study of Sichuan Province and the Department of Laboratory Medicine, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, 610075, China
| | - Chao Qu
- Department of Ophthalmology, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, 610075, China
| | - Shujin Li
- The Key Laboratory for Human Disease Gene Study of Sichuan Province and the Department of Laboratory Medicine, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, 610075, China
| | - Jie Li
- Department of Ophthalmology, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, 610075, China
| | - Mu Yang
- The Key Laboratory for Human Disease Gene Study of Sichuan Province and the Department of Laboratory Medicine, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, 610075, China
| | - Biao Wu
- School of Ophthalmology and Optometry, Wenzhou Medical College, Wenzhou, 325035, China
| | - Ran Chen
- School of Ophthalmology and Optometry, Wenzhou Medical College, Wenzhou, 325035, China
| | - Guo Huang
- The Key Laboratory for Human Disease Gene Study of Sichuan Province and the Department of Laboratory Medicine, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, 610075, China
| | - Ling Zhong
- The Key Laboratory for Human Disease Gene Study of Sichuan Province and the Department of Laboratory Medicine, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, 610075, China
| | - Hongjie Yang
- Department of Organ Transplant Center, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, 610075, China
| | - Man Yu
- Department of Ophthalmology, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, 610075, China
| | - Yi Shi
- The Key Laboratory for Human Disease Gene Study of Sichuan Province and the Department of Laboratory Medicine, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, 610075, China
| | - Changguan Wang
- Department of Ophthalmology, Peking University Third Hospital, Beijing, 100730, China
| | - Houbin Zhang
- The Key Laboratory for Human Disease Gene Study of Sichuan Province and the Department of Laboratory Medicine, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, 610075, China
| | - Wei Chen
- School of Ophthalmology and Optometry, Wenzhou Medical College, Wenzhou, 325035, China
| | - Zhenglin Yang
- The Key Laboratory for Human Disease Gene Study of Sichuan Province and the Department of Laboratory Medicine, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, 610075, China.
- Research Unit for Blindness Prevention of Chinese Academy of Medical Sciences (2019RU026), Sichuan Academy of Medical Sciences, Chengdu, 610075, China.
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8
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Dias SB, de Lemos L, Sousa L, Bitoque DB, Silva GA, Seabra MC, Tenreiro S. Age-Related Changes of the Synucleins Profile in the Mouse Retina. Biomolecules 2023; 13:biom13010180. [PMID: 36671565 PMCID: PMC9855780 DOI: 10.3390/biom13010180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 12/28/2022] [Accepted: 01/11/2023] [Indexed: 01/18/2023] Open
Abstract
Alpha-synuclein (aSyn) plays a central role in Parkinson's disease (PD) and has been extensively studied in the brain. This protein is part of the synuclein family, which is also composed of beta-synuclein (bSyn) and gamma-synuclein (gSyn). In addition to its neurotoxic role, synucleins have important functions in the nervous system, modulating synaptic transmission. Synucleins are expressed in the retina, but they have been poorly characterized. However, there is evidence that they are important for visual function and that they can play a role in retinal degeneration. This study aimed to profile synucleins in the retina of naturally aged mice and to correlate their patterns with specific retinal cells. With aging, we observed a decrease in the thickness of specific retinal layers, accompanied by an increase in glial reactivity. Moreover, the aSyn levels decreased, whereas bSyn increased with aging. The colocalization of both proteins was decreased in the inner plexiform layer (IPL) of the aged retina. gSyn presented an age-related decrease at the inner nuclear layer but was not significantly changed in the ganglion cell layer. The synaptic marker synaptophysin was shown to be preferentially colocalized with aSyn in the IPL with aging. At the same time, aSyn was found to exist at the presynaptic endings of bipolar cells and was affected by aging. Overall, this study suggests that physiological aging can be responsible for changes in the retinal tissue, implicating functional alterations that could affect synuclein family function.
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Affiliation(s)
- Sarah Batista Dias
- iNOVA4Health, NOVA Medical School|Faculdade de Ciências Médicas, NMS|FCM, Universidade Nova de Lisboa, 1169-056 Lisboa, Portugal
| | - Luísa de Lemos
- iNOVA4Health, NOVA Medical School|Faculdade de Ciências Médicas, NMS|FCM, Universidade Nova de Lisboa, 1169-056 Lisboa, Portugal
| | - Luís Sousa
- iNOVA4Health, NOVA Medical School|Faculdade de Ciências Médicas, NMS|FCM, Universidade Nova de Lisboa, 1169-056 Lisboa, Portugal
| | - Diogo B. Bitoque
- iNOVA4Health, NOVA Medical School|Faculdade de Ciências Médicas, NMS|FCM, Universidade Nova de Lisboa, 1169-056 Lisboa, Portugal
| | - Gabriela Araújo Silva
- iNOVA4Health, NOVA Medical School|Faculdade de Ciências Médicas, NMS|FCM, Universidade Nova de Lisboa, 1169-056 Lisboa, Portugal
| | - Miguel C. Seabra
- iNOVA4Health, NOVA Medical School|Faculdade de Ciências Médicas, NMS|FCM, Universidade Nova de Lisboa, 1169-056 Lisboa, Portugal
- UCL Institute of Ophthalmology, London EC1V 9EL, UK
| | - Sandra Tenreiro
- iNOVA4Health, NOVA Medical School|Faculdade de Ciências Médicas, NMS|FCM, Universidade Nova de Lisboa, 1169-056 Lisboa, Portugal
- Correspondence:
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9
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Jauregui‐Lozano J, Escobedo S, Easton A, Lanman N, Weake VM, Hall H. Proper control of R-loop homeostasis is required for maintenance of gene expression and neuronal function during aging. Aging Cell 2022; 21:e13554. [PMID: 35048512 PMCID: PMC8844117 DOI: 10.1111/acel.13554] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 12/03/2021] [Accepted: 01/03/2022] [Indexed: 01/25/2023] Open
Abstract
Age‐related loss of cellular function and increased cell death are characteristic hallmarks of aging. While defects in gene expression and RNA metabolism have been linked with age‐associated human neuropathies, it is not clear how the changes that occur in aging neurons contribute to loss of gene expression homeostasis. R‐loops are RNA–DNA hybrids that typically form co‐transcriptionally via annealing of the nascent RNA to the template DNA strand, displacing the non‐template DNA strand. Dysregulation of R‐loop homeostasis has been associated with both transcriptional impairment and genome instability. Importantly, a growing body of evidence links R‐loop accumulation with cellular dysfunction, increased cell death, and chronic disease onset. Here, we characterized the R‐loop landscape in aging Drosophila melanogaster photoreceptor neurons and showed that bulk R‐loop levels increased with age. Further, genome‐wide mapping of R‐loops revealed that transcribed genes accumulated R‐loops over gene bodies during aging, which correlated with decreased expression of long and highly expressed genes. Importantly, while photoreceptor‐specific down‐regulation of Top3β, a DNA/RNA topoisomerase associated with R‐loop resolution, lead to decreased visual function, over‐expression of Top3β or nuclear‐localized RNase H1, which resolves R‐loops, enhanced positive light response during aging. Together, our studies highlight the functional link between dysregulation of R‐loop homeostasis, gene expression, and visual function during aging.
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Affiliation(s)
| | - Spencer Escobedo
- Department of Biochemistry Purdue University West Lafayette Indiana USA
| | - Alyssa Easton
- Department of Agricultural and Biological Engineering Purdue University West Lafayette Indiana USA
| | - Nadia A. Lanman
- Department of Comparative Pathobiology College of Veterinary Medicine Purdue University West Lafayette Indiana USA
- Purdue University Center for Cancer Research Purdue University West Lafayette Indiana USA
| | - Vikki M. Weake
- Department of Biochemistry Purdue University West Lafayette Indiana USA
- Purdue University Center for Cancer Research Purdue University West Lafayette Indiana USA
| | - Hana Hall
- Department of Biochemistry Purdue University West Lafayette Indiana USA
- Purdue Institute for Integrative Neuroscience Purdue University West Lafayette Indiana USA
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10
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Jauregui-Lozano J, Hall H, Stanhope SC, Bakhle K, Marlin MM, Weake VM. The Clock:Cycle complex is a major transcriptional regulator of Drosophila photoreceptors that protects the eye from retinal degeneration and oxidative stress. PLoS Genet 2022; 18:e1010021. [PMID: 35100266 PMCID: PMC8830735 DOI: 10.1371/journal.pgen.1010021] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Revised: 02/10/2022] [Accepted: 01/08/2022] [Indexed: 12/28/2022] Open
Abstract
The aging eye experiences physiological changes that include decreased visual function and increased risk of retinal degeneration. Although there are transcriptomic signatures in the aging retina that correlate with these physiological changes, the gene regulatory mechanisms that contribute to cellular homeostasis during aging remain to be determined. Here, we integrated ATAC-seq and RNA-seq data to identify 57 transcription factors that showed differential activity in aging Drosophila photoreceptors. These 57 age-regulated transcription factors include two circadian regulators, Clock and Cycle, that showed sustained increased activity during aging. When we disrupted the Clock:Cycle complex by expressing a dominant negative version of Clock (ClkDN) in adult photoreceptors, we observed changes in expression of 15–20% of genes including key components of the phototransduction machinery and many eye-specific transcription factors. Using ATAC-seq, we showed that expression of ClkDN in photoreceptors leads to changes in activity of 37 transcription factors and causes a progressive decrease in global levels of chromatin accessibility in photoreceptors. Supporting a key role for Clock-dependent transcription in the eye, expression of ClkDN in photoreceptors also induced light-dependent retinal degeneration and increased oxidative stress, independent of light exposure. Together, our data suggests that the circadian regulators Clock and Cycle act as neuroprotective factors in the aging eye by directing gene regulatory networks that maintain expression of the phototransduction machinery and counteract oxidative stress. Age-associated changes to the retinal transcriptome often correlate with physiological changes, such as loss of visual function and increase in cell death. However, the mechanisms that contribute to these transcriptomic changes are poorly understood. Here, we used a genomics/bioinformatics approach to identify transcription factor binding sites with differential activity in aging Drosophila retina outer photoreceptors. Amongst these age-regulated transcription factors, we identify the circadian regulators Clock and Cycle. Using a genetics approach, we find that photoreceptor-specific disruption of the Clock:Cycle complex makes the Drosophila eye susceptible to light-dependent retinal degeneration, and light-independent increase of oxidative stress, showing that a functional circadian clock contributes to visual health and function in Drosophila. Because disruption of circadian rhythms has been associated with the onset of several age-related eye diseases, our data shows that the Drosophila retina serves as a useful model to study how disruption of the circadian clock contributes to neurodegeneration in the retina.
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Affiliation(s)
- Juan Jauregui-Lozano
- Department of Biochemistry, Purdue University, West Lafayette, Indiana, United States of America
| | - Hana Hall
- Department of Biochemistry, Purdue University, West Lafayette, Indiana, United States of America
- Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, Indiana, United States of America
| | - Sarah C. Stanhope
- Department of Biochemistry, Purdue University, West Lafayette, Indiana, United States of America
| | - Kimaya Bakhle
- Department of Biochemistry, Purdue University, West Lafayette, Indiana, United States of America
| | - Makayla M. Marlin
- Department of Biochemistry, Purdue University, West Lafayette, Indiana, United States of America
| | - Vikki M. Weake
- Department of Biochemistry, Purdue University, West Lafayette, Indiana, United States of America
- Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, Indiana, United States of America
- Purdue Center for Cancer Research, Purdue University, West Lafayette, Indiana, United States of America
- * E-mail:
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11
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Quantitative Proteomic and Metabolomic Profiling Reveals Altered Mitochondrial Metabolism and Folate Biosynthesis Pathways in the Aging Drosophila Eye. Mol Cell Proteomics 2021; 20:100127. [PMID: 34332122 PMCID: PMC8385154 DOI: 10.1016/j.mcpro.2021.100127] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Revised: 07/09/2021] [Accepted: 07/21/2021] [Indexed: 11/26/2022] Open
Abstract
Aging is associated with increased risk of ocular disease, suggesting that age-associated molecular changes in the eye increase its vulnerability to damage. Although there are common pathways involved in aging at an organismal level, different tissues and cell types exhibit specific changes in gene expression with advanced age. Drosophila melanogaster is an established model system for studying aging and neurodegenerative disease that also provides a valuable model for studying age-associated ocular disease. Flies, like humans, exhibit decreased visual function and increased risk of retinal degeneration with age. Here, we profiled the aging proteome and metabolome of the Drosophila eye and compared these data with age-associated transcriptomic changes from both eyes and photoreceptors to identify alterations in pathways that could lead to age-related phenotypes in the eye. Of note, the proteomic and metabolomic changes observed in the aging eye are distinct from those observed in the head or whole fly, suggesting that tissue-specific changes in protein abundance and metabolism occur in the aging fly. Our integration of the proteomic, metabolomic, and transcriptomic data reveals that changes in metabolism, potentially due to decreases in availability of B vitamins, together with chronic activation of the immune response, may underpin many of the events observed in the aging Drosophila eye. We propose that targeting these pathways in the genetically tractable Drosophila system may help to identify potential neuroprotective approaches for neurodegenerative and age-related ocular diseases. Data are available via ProteomeXchange with identifier PXD027090. Tissue-specific changes in protein abundance occur in the aging Drosophila eye. Increase in mitochondrial metabolism enzyme abundance in the aging eye. Decrease in corneal lens protein abundance and calcium buffering in the aging eye. Dysregulated metabolism impacts vitamin B and methionine metabolism in the aging eye.
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12
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Campello L, Singh N, Advani J, Mondal AK, Corso-Diaz X, Swaroop A. Aging of the Retina: Molecular and Metabolic Turbulences and Potential Interventions. Annu Rev Vis Sci 2021; 7:633-664. [PMID: 34061570 DOI: 10.1146/annurev-vision-100419-114940] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Multifaceted and divergent manifestations across tissues and cell types have curtailed advances in deciphering the cellular events that accompany advanced age and contribute to morbidities and mortalities. Increase in human lifespan during the past century has heightened awareness of the need to prevent age-associated frailty of neuronal and sensory systems to allow a healthy and productive life. In this review, we discuss molecular and physiological attributes of aging of the retina, with a goal of understanding age-related impairment of visual function. We highlight the epigenome-metabolism nexus and proteostasis as key contributors to retinal aging and discuss lifestyle changes as potential modulators of retinal function. Finally, we deliberate promising intervention strategies for promoting healthy aging of the retina for improved vision. Expected final online publication date for the Annual Review of Vision Science, Volume 7 is September 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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Affiliation(s)
- Laura Campello
- Neurobiology, Neurodegeneration and Repair Laboratory, National Eye Institute, National Institutes of Health, Bethesda, Maryland 20892, USA;
| | - Nivedita Singh
- Neurobiology, Neurodegeneration and Repair Laboratory, National Eye Institute, National Institutes of Health, Bethesda, Maryland 20892, USA;
| | - Jayshree Advani
- Neurobiology, Neurodegeneration and Repair Laboratory, National Eye Institute, National Institutes of Health, Bethesda, Maryland 20892, USA;
| | - Anupam K Mondal
- Neurobiology, Neurodegeneration and Repair Laboratory, National Eye Institute, National Institutes of Health, Bethesda, Maryland 20892, USA;
| | - Ximena Corso-Diaz
- Neurobiology, Neurodegeneration and Repair Laboratory, National Eye Institute, National Institutes of Health, Bethesda, Maryland 20892, USA;
| | - Anand Swaroop
- Neurobiology, Neurodegeneration and Repair Laboratory, National Eye Institute, National Institutes of Health, Bethesda, Maryland 20892, USA;
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13
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Berkowitz BA, Podolsky RH, Childers KL, Roberts R, Schneider M, Graffice E, Sinan K, Berri A, Harp L. Correcting QUEST Magnetic Resonance Imaging-Sensitive Free Radical Production in the Outer Retina In Vivo Does Not Correct Reduced Visual Performance in 24-Month-Old C57BL/6J Mice. Invest Ophthalmol Vis Sci 2021; 62:24. [PMID: 34036313 PMCID: PMC8164372 DOI: 10.1167/iovs.62.6.24] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
Purpose To test the hypothesis that acutely correcting a sustained presence of outer retina free radicals measured in vivo in 24-month-old mice corrects their reduced visual performance. Methods Male C57BL/6J mice two and 24 months old were noninvasively evaluated for unremitted production of paramagnetic free radicals based on whether 1/T1 in retinal laminae are reduced after acute antioxidant administration (QUEnch-assiSTed [QUEST] magnetic resonance imaging [MRI]). Superoxide production was measured in freshly excised retina (lucigenin assay). Combining acute antioxidant administration with optical coherence tomography (i.e., QUEST OCT) tested for excessive free radical–induced shrinkage of the subretinal space volume. Combining antioxidant administration with optokinetic tracking tested for a contribution of uncontrolled free radical production to cone-based visual performance declines. Results At two months, antioxidants had no effect on 1/T1 in vivo in any retinal layer. At 24 months, antioxidants reduced 1/T1 only in superior outer retina. No age-related change in retinal superoxide production was measured ex vivo, suggesting that free radical species other than superoxide contributed to the positive QUEST MRI signal at 24 months. Also, subretinal space volume did not show evidence for age-related shrinkage and was unresponsive to antioxidants. Finally, visual performance declined with age and was not restored by antioxidants that were effective per QUEST MRI. Conclusions An ongoing uncontrolled production of outer retina free radicals as measured in vivo in 24 mo C57BL/6J mice appears to be insufficient to explain reductions in visual performance.
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Affiliation(s)
- Bruce A Berkowitz
- Department of Ophthalmology, Visual and Anatomical Sciences, Wayne State University School of Medicine, Detroit, Michigan, United States
| | - Robert H Podolsky
- Beaumont Research Institute, Beaumont Health, Royal Oak, Michigan, United States
| | - Karen Lins Childers
- Beaumont Research Institute, Beaumont Health, Royal Oak, Michigan, United States
| | - Robin Roberts
- Department of Ophthalmology, Visual and Anatomical Sciences, Wayne State University School of Medicine, Detroit, Michigan, United States
| | - Michael Schneider
- Department of Ophthalmology, Visual and Anatomical Sciences, Wayne State University School of Medicine, Detroit, Michigan, United States
| | - Emma Graffice
- Department of Ophthalmology, Visual and Anatomical Sciences, Wayne State University School of Medicine, Detroit, Michigan, United States
| | - Kenan Sinan
- Department of Ophthalmology, Visual and Anatomical Sciences, Wayne State University School of Medicine, Detroit, Michigan, United States
| | - Ali Berri
- Department of Ophthalmology, Visual and Anatomical Sciences, Wayne State University School of Medicine, Detroit, Michigan, United States
| | - Lamis Harp
- Department of Ophthalmology, Visual and Anatomical Sciences, Wayne State University School of Medicine, Detroit, Michigan, United States
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14
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Ramírez AI, Fernández-Albarral JA, Hoz RD, López-Cuenca I, Salobrar-García E, Rojas P, Valiente-Soriano FJ, Avilés-Trigueros M, Villegas-Pérez MP, Vidal-Sanz M, Triviño A, Salazar JJ, Ramírez JM. Microglial changes in the early aging stage in a healthy retina and an experimental glaucoma model. PROGRESS IN BRAIN RESEARCH 2020; 256:125-149. [PMID: 32958210 DOI: 10.1016/bs.pbr.2020.05.024] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Glaucoma is an age-related neurodegenerative disease that begins at the onset of aging. In this disease, there is an involvement of the immune system and therefore of the microglia. The purpose of this study is to evaluate the microglial activation using a mouse model of ocular hypertension (OHT) at the onset of aging. For this purpose, we used both naive and ocular hypertensives of 15-month-old mice (early stage of aging). In the latter, we analyzed the OHT eyes and the eyes contralateral to them to compare them with their aged controls. In the eyes of aged naive, aged OHT and aged contralateral eyes, microglial changes were observed compared to the young mice, including: (i) aged naive vs young naive: An increased soma size and vertical processes; (ii) aged OHT eyes vs young OHT eyes: A decrease in the area of the retina occupied by Iba-1 cells and in vertical processes; and (iii) aged contralateral vs young contralateral: A decrease in the soma size and arbor area and an increase in the number of microglia in the outer segment layer. Aged OHT eyes and the eyes contralateral to them showed an up-regulation of the CD68 expression in the branched microglia and a down-regulation in the MHCII and P2RY12 expression with respect to the eyes of young OHT mice. Conclusion: in the early phase of aging, morphological microglial changes along with changes in the expression of MHCII, CD68 and P2RY12, in both naive and OHT mice. These changes appear in aged OHT eyes and the eyes contralateral to them eyes.
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Affiliation(s)
- Ana I Ramírez
- Instituto de Investigaciones Oftalmológicas Ramón Castroviejo, Universidad Complutense de Madrid, Madrid, Spain; Facultad de Óptica y Optometría, Departamento de Inmunología, Oftalmología y ORL, Universidad Complutense de Madrid, Madrid, Spain
| | - José A Fernández-Albarral
- Instituto de Investigaciones Oftalmológicas Ramón Castroviejo, Universidad Complutense de Madrid, Madrid, Spain
| | - Rosa de Hoz
- Instituto de Investigaciones Oftalmológicas Ramón Castroviejo, Universidad Complutense de Madrid, Madrid, Spain; Facultad de Óptica y Optometría, Departamento de Inmunología, Oftalmología y ORL, Universidad Complutense de Madrid, Madrid, Spain
| | - Inés López-Cuenca
- Instituto de Investigaciones Oftalmológicas Ramón Castroviejo, Universidad Complutense de Madrid, Madrid, Spain
| | - Elena Salobrar-García
- Instituto de Investigaciones Oftalmológicas Ramón Castroviejo, Universidad Complutense de Madrid, Madrid, Spain; Facultad de Óptica y Optometría, Departamento de Inmunología, Oftalmología y ORL, Universidad Complutense de Madrid, Madrid, Spain
| | - Pilar Rojas
- Instituto de Investigaciones Oftalmológicas Ramón Castroviejo, Universidad Complutense de Madrid, Madrid, Spain; Hospital General Universitario Gregorio Marañón, Instituto Oftálmico de Madrid, Madrid, Spain
| | - Francisco Javier Valiente-Soriano
- Department of Ophthalmology, University of Murcia and Instituto Murciano de Investigación Biosanitaria-Virgen de la Arrixaca (IMIB-Arrixaca), Murcia, Spain
| | - Marcelino Avilés-Trigueros
- Department of Ophthalmology, University of Murcia and Instituto Murciano de Investigación Biosanitaria-Virgen de la Arrixaca (IMIB-Arrixaca), Murcia, Spain
| | - María Paz Villegas-Pérez
- Department of Ophthalmology, University of Murcia and Instituto Murciano de Investigación Biosanitaria-Virgen de la Arrixaca (IMIB-Arrixaca), Murcia, Spain
| | - Manuel Vidal-Sanz
- Department of Ophthalmology, University of Murcia and Instituto Murciano de Investigación Biosanitaria-Virgen de la Arrixaca (IMIB-Arrixaca), Murcia, Spain
| | - Alberto Triviño
- Instituto de Investigaciones Oftalmológicas Ramón Castroviejo, Universidad Complutense de Madrid, Madrid, Spain; Facultad de Medicina, Departamento de Inmunología, Oftalmología y ORL, Universidad Complutense de Madrid, Spain
| | - Juan J Salazar
- Instituto de Investigaciones Oftalmológicas Ramón Castroviejo, Universidad Complutense de Madrid, Madrid, Spain; Facultad de Óptica y Optometría, Departamento de Inmunología, Oftalmología y ORL, Universidad Complutense de Madrid, Madrid, Spain.
| | - José M Ramírez
- Instituto de Investigaciones Oftalmológicas Ramón Castroviejo, Universidad Complutense de Madrid, Madrid, Spain; Facultad de Medicina, Departamento de Inmunología, Oftalmología y ORL, Universidad Complutense de Madrid, Spain.
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15
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Jorge L, Canário N, Quental H, Bernardes R, Castelo-Branco M. Is the Retina a Mirror of the Aging Brain? Aging of Neural Retina Layers and Primary Visual Cortex Across the Lifespan. Front Aging Neurosci 2020; 11:360. [PMID: 31998115 PMCID: PMC6961569 DOI: 10.3389/fnagi.2019.00360] [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: 08/21/2019] [Accepted: 12/10/2019] [Indexed: 01/13/2023] Open
Abstract
How aging concomitantly modulates the structural integrity of the brain and retina in healthy individuals remains an outstanding question. Given the strong bottom-up retinocortical connectivity, it is important to study how these structures co-evolve during healthy aging in order to unravel mechanisms that may affect the physiological integrity of both structures. For the 56 participants in the study, primary visual cortex (BA17), as well as frontal, parietal and temporal regions thicknesses were measured in T1-weighted magnetic resonance imaging (MRI), and retinal macular thickness (10 neuroretinal layers) was measured by optical coherence tomography (OCT) imaging. We investigated the statistical association of these measures and their age dependence. We found an age-related decay of primary visual cortical thickness that was significantly correlated with a decrease in global and multiple layer retinal thicknesses. The atrophy of both structures might jointly account for the decline of various visual capacities that accompany the aging process. Furthermore, associations with other cortical regions suggest that retinal status may index cortical integrity in general.
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Affiliation(s)
- Lília Jorge
- Coimbra Institute for Biomedical Imaging and Translational Research (CIBIT), University of Coimbra, Coimbra, Portugal.,Institute for Nuclear Sciences Applied to Health (ICNAS), University of Coimbra, Coimbra, Portugal
| | - Nádia Canário
- Coimbra Institute for Biomedical Imaging and Translational Research (CIBIT), University of Coimbra, Coimbra, Portugal.,Institute for Nuclear Sciences Applied to Health (ICNAS), University of Coimbra, Coimbra, Portugal
| | - Hugo Quental
- Coimbra Institute for Biomedical Imaging and Translational Research (CIBIT), University of Coimbra, Coimbra, Portugal.,Institute for Nuclear Sciences Applied to Health (ICNAS), University of Coimbra, Coimbra, Portugal
| | - Rui Bernardes
- Coimbra Institute for Biomedical Imaging and Translational Research (CIBIT), University of Coimbra, Coimbra, Portugal.,Institute for Nuclear Sciences Applied to Health (ICNAS), University of Coimbra, Coimbra, Portugal.,Faculty of Medicine, University of Coimbra, Coimbra, Portugal
| | - Miguel Castelo-Branco
- Coimbra Institute for Biomedical Imaging and Translational Research (CIBIT), University of Coimbra, Coimbra, Portugal.,Institute for Nuclear Sciences Applied to Health (ICNAS), University of Coimbra, Coimbra, Portugal.,Faculty of Medicine, University of Coimbra, Coimbra, Portugal
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16
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Shaaban YM, Badran TAF. The effect of oral contraceptive pills on the macula, the retinal nerve fiber layer, the ganglion cell layer and the choroidal thickness. BMC Ophthalmol 2019; 19:250. [PMID: 31823761 PMCID: PMC6904990 DOI: 10.1186/s12886-019-1263-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Accepted: 12/02/2019] [Indexed: 12/02/2022] Open
Abstract
Backgroun To evaluate the effect of oral contraceptive pills (OCP) on the macula, the retinal nerve fiber layer (RNFL), the ganglion cell layer (GCL), and the choroidal thickness (CT). Methods In this prospective observational cross-sectional study, 60 eyes of 30 healthy women taking monophasic OCP (0.03 mg ethinylestradiol and 0.15 mg levonorgestrel) for contraception for at least 1 year were compared with 60 eyes of a control group of 30 healthy women who were not taking any OCP. Spectral-Domain Optical Coherence Tomography (SD-OCT) was used to evaluate the macula, the RNFL, the GCL, and the CT. Measurements were taken in the follicular phase (day 3) of the last menstrual cycle in all women. The body mass index (BMI) scores of all participants were also recorded. Results No disparity in terms of age and BMI between both groups was observed (p = 0.444, p = 0.074, respectively). All the macular parameters measurements were considerably lower in the OCP group compared to the control group (p < 0.001). Also, the RNFL thickness, the GCL thickness, and the CT were all significantly thinner in the OCP group (p < 0.001). Conclusions The use of OCP can cause significant changes in the retina and choroid thickness over 1 year period. The women who are using OCP for a longer duration could have some eye problems. OCT should be routinely done for follow up. Further long term studies are required, using different preparations of OCP. It is important to find out when this thickness alterations can be clinically significant or symptomatic and if these changes are reversible or not.
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Affiliation(s)
- Yasmine Maher Shaaban
- Department of Ophthalmology, Faculty of Medicine, Ain Shams University, Abbassyia, Cairo, 11566, Egypt. .,The Eye Subspecialty Center, (ESC), 18 El Khalifa El Maamoun Street, Heliopolis, Cairo, 11402, Egypt. .,, Cairo, Egypt.
| | - Tamer Abdel Fattah Badran
- Department of Ophthalmology, Faculty of Medicine, Ain Shams University, Abbassyia, Cairo, 11566, Egypt.,The Eye Subspecialty Center, (ESC), 18 El Khalifa El Maamoun Street, Heliopolis, Cairo, 11402, Egypt
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17
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Zhang X, Zhu J, Chen X, Jie-Qiong Z, Li X, Luo L, Huang H, Liu W, Zhou X, Yan J, Lin S, Ye J. Interferon Regulatory Factor 3 Deficiency Induces Age-Related Alterations of the Retina in Young and Old Mice. Front Cell Neurosci 2019; 13:272. [PMID: 31281243 PMCID: PMC6596281 DOI: 10.3389/fncel.2019.00272] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2019] [Accepted: 06/05/2019] [Indexed: 12/20/2022] Open
Abstract
Age-related changes in visual function and retina structure are very common in aged animals, but the underlying mechanisms of these changes remain unclear. Here we report that the expression of interferon regulatory factor 3 (IRF3), a critical immune regulatory factor, is dramatically down-regulated in mouse retinas during aging. To address the role of IRF3 in the retina, we examined the structure and function of retinas in young (3–4 months) and old (22–24 months) Irf3-/- mice in comparison to age-matched wildtype (WT) mice. We found that IRF3 deletion resulted in impaired electroretinogram (ERG) responses and decreased retinal thickness in both young and old mice. In addition, numerous synapses of the outer plexiform layer (OPL) were found obviously extending into outer nuclear layer (ONL) in Irf3-/- mice, along with a reduction of the average synapse density in the OPL. These changes suggest that IRF3 deletion may accelerate retinal senescence. In support of this hypothesis, a number of classic senescence-associated markers were found in remarkably elevated level in Irf3-/- retina, including p53, p16INK4a, inositol-requiring enzyme 1α (IREα), p-H2A.X and promyelocytic leukemia protein (PML). Overall, our results indicate that maintenance normal IRF3 levels is necessary for retinal structure and function and suggest that IRF3 is an important regulator of retinal senescence.
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Affiliation(s)
- Xi Zhang
- Department of Ophthalmology, Institute of Surgery Research, Army Medical Center of PLA (Daping Hospital), Army Medical University, Chongqing, China
| | - Jingyi Zhu
- Department of Ophthalmology, Institute of Surgery Research, Army Medical Center of PLA (Daping Hospital), Army Medical University, Chongqing, China
| | - Xianjun Chen
- Department of Histology and Embryology, Chongqing Key Laboratory of Neurobiology, Army Medical University, Chongqing, China
| | - Zhang Jie-Qiong
- Department of Ophthalmology, Institute of Surgery Research, Army Medical Center of PLA (Daping Hospital), Army Medical University, Chongqing, China
| | - Xue Li
- Department of Ophthalmology, Institute of Surgery Research, Army Medical Center of PLA (Daping Hospital), Army Medical University, Chongqing, China
| | - Linlin Luo
- Department of Ophthalmology, Institute of Surgery Research, Army Medical Center of PLA (Daping Hospital), Army Medical University, Chongqing, China
| | - Huang Huang
- Institute of Immunology, Army Medical University, Chongqing, China
| | - Wenyi Liu
- Department of Ophthalmology, Institute of Surgery Research, Army Medical Center of PLA (Daping Hospital), Army Medical University, Chongqing, China
| | - Xinyuan Zhou
- Institute of Immunology, Army Medical University, Chongqing, China
| | - Jun Yan
- Department of Ophthalmology, Institute of Surgery Research, Army Medical Center of PLA (Daping Hospital), Army Medical University, Chongqing, China
| | - Sen Lin
- Department of Ophthalmology, Institute of Surgery Research, Army Medical Center of PLA (Daping Hospital), Army Medical University, Chongqing, China
| | - Jian Ye
- Department of Ophthalmology, Institute of Surgery Research, Army Medical Center of PLA (Daping Hospital), Army Medical University, Chongqing, China
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18
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Liang ST, Audira G, Juniardi S, Chen JR, Lai YH, Du ZC, Lin DS, Hsiao CD. Zebrafish Carrying pycr1 Gene Deficiency Display Aging and Multiple Behavioral Abnormalities. Cells 2019; 8:cells8050453. [PMID: 31091804 PMCID: PMC6562453 DOI: 10.3390/cells8050453] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Revised: 04/28/2019] [Accepted: 05/09/2019] [Indexed: 12/22/2022] Open
Abstract
Aging is a natural process that internal gene control and external stimuli mediate. Clinical data pointed out that homozygotic or heterozygotic mutation in the pyrroline-5-carboxylate reductase 1 (PYCR1) gene in humans caused cutis laxa (ARCL) disease, with progeroid appearance, lax and wrinkled skin, joint laxity, osteopenia, and mental retardation phenotypes. In this study, we aimed to generate pycr1 knockout (KO) zebrafish and carried out biochemical characterizations and behavior analyses. Marked apoptosis and senescence were detected in pycr1 KO zebrafish, which started from embryos/larvae stage. Biochemical assays showed that adult pycr1 KO fish have significantly reduced proline and extracellular matrix contents, lowered energy, and diminished superoxide dismutase (SOD) and telomerase activity when compared to the wild type fish, which suggested the pycr1 KO fish may have dysfunction in mitochondria. The pycr1 KO fish were viable; however, displayed progeria-like phenotype from the 4 months old and reach 50% mortality around six months old. In adult stage, we found that pycr1 KO fish showed reduced locomotion activity, aggression, predator avoidance, social interaction interest, as well as dysregulated color preference and circadian rhythm. In summary, we have identified multiple behavioral alterations in a novel fish model for aging with pycr1 gene loss-of-function by behavioral tests. This animal model may not only provide a unique vertebrate model to screen potential anti-aging drugs in the future, but also be an excellent in vivo model towards a better understanding of the corresponding behavioral alterations that accompany aging.
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Affiliation(s)
- Sung-Tzu Liang
- Department of Bioscience Technology, Chung Yuan Christian University, Chung-Li 32023, Taiwan.
| | - Gilbert Audira
- Department of Bioscience Technology, Chung Yuan Christian University, Chung-Li 32023, Taiwan.
- Department of Chemistry, Chung Yuan Christian University, Chung-Li 32023, Taiwan.
| | - Stevhen Juniardi
- Department of Bioscience Technology, Chung Yuan Christian University, Chung-Li 32023, Taiwan.
| | - Jung-Ren Chen
- Department of Biological Science & Technology, College of Medicine, I-Shou University, Kaohsiung 84001, Taiwan.
| | - Yu-Heng Lai
- Department of Chemistry, Chinese Culture University, Taipei 11114, Taiwan.
| | - Zheng-Cai Du
- Guangxi Scientific Experimental Center of Traditional Chinese Medicine, Guangxi University of Chinese Medicine, Nanning 530200, China.
- Guangxi Key Laboratory of Efficacy Study on Chinese Materia Medica, Guangxi University of Chinese Medicine, Nanning 530200, China.
| | - Dar-Shong Lin
- Department of Pediatrics, Mackay Memorial Hospital, Taipei 252, Taiwan.
- Department of Medical Research, Mackay Memorial Hospital, Taipei 252, Taiwan.
- Department of Medicine, Mackay Medical College, New Taipei 252, Taiwan.
| | - Chung-Der Hsiao
- Department of Bioscience Technology, Chung Yuan Christian University, Chung-Li 32023, Taiwan.
- Department of Chemistry, Chung Yuan Christian University, Chung-Li 32023, Taiwan.
- Center for Biomedical Technology, Chung Yuan Christian University, Chung-Li 32023, Taiwan.
- Center for Nanotechnology, Chung Yuan Christian University, Chung-Li 32023, Taiwan.
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19
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Abstract
Osteopontin (OPN) is a secreted glycosylated phosphoprotein that influences cell survival, inflammation, migration, and homeostasis after injury. As the role of OPN in the retina remains unclear, this study issue was addressed by aiming to study how the absence of OPN in knock-out mice affects the retina and the influence of age on these effects. The study focused on retinal ganglion cells (RGCs) and glial cells (astrocytes, Müller cells, and resident microglia) in 3- and 20-month-old mice. The number of RGCs in the retina was quantified and the area occupied by astrocytes was measured. In addition, the morphology of Müller cells and microglia was examined in retinal sections. The deficiency in OPN reduces RGC density by 25.09% at 3 months of age and by 60.37% at 20 months of age. The astrocyte area was also reduced by 51.01% in 3-month-old mice and by 57.84% at 20 months of age, although Müller glia and microglia did not seem to be affected by the lack of OPN. This study demonstrates the influence of OPN on astrocytes and RGCs, whereby the absence of OPN in the retina diminishes the area occupied by astrocytes and produces a secondary reduction in the number of RGCs. Accordingly, OPN could be a target to develop therapies to combat neurodegenerative diseases and astrocytes may represent a key mediator of such effects.
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Comparative localization of cystathionine beta synthases and cystathionine gamma lyase in canine, non-human primate and human retina. Exp Eye Res 2019; 181:72-84. [PMID: 30653965 DOI: 10.1016/j.exer.2019.01.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Revised: 12/18/2018] [Accepted: 01/03/2019] [Indexed: 12/15/2022]
Abstract
Chronic exposure of the retina to light and high concentrations of polyunsaturated fatty acid in photoreceptor cells make this tissue susceptible to oxidative damage. As retinal degenerative diseases are associated with photoreceptor degeneration, the antioxidant activity of both hydrogen sulfide (H2S) and glutathione (GSH) may play an important role in ameliorating disease progression. H2S production is driven by cystathionine-γ-lyase (CSE) and cystathionine-β-synthase (CBS), the key enzymes that also drive transsulfuration pathway (TSP) necessary for GSH production. As it is currently unclear whether localized production of either H2S or GSH contributes to retinal homeostasis, we undertook a comparative analysis of CBS and CSE expression in canine, non-human primate (NHP) and human retinas to determine if these antioxidants could play a regulatory role in age-related or disease-associated retinal degeneration. Retinas from normal dogs, NHPs and humans were used for the study. Laser capture microdissection (LCM) was performed to isolate individual layers of the canine retina and analyze CBS and CSE gene expression by qRT-PCR. Immunohistochemistry and western blotting were performed for CBS and CSE labeling and protein expression in dog, NHP, and human retina, respectively. Using qRT-PCR, western blot, and immunohistochemistry (IHC), we showed that CBS and CSE are expressed in the canine, NHP, and human retina. IHC results from canine retina demonstrated increased expression levels of CBS but not CSE with post-developmental aging. IHC results also showed non-overlapping localization of both proteins with CBS presenting in rods, amacrine, horizontal, and nerve fiber cell layers while CSE was expressed by RPE, cones and Mϋller cells. Finally, we demonstrated that these enzymes localized to all three layers of canine, NHP and human retina: photoreceptors, outer plexiform layer (OPL) and notably in the ganglion cells layer/nerve fiber layer (GCL/NFL). QRT-PCR performed using RNA extracted from tissues isolated from these cell layers using laser capture microdissection (LCM) confirmed that each of CBS and CSE are expressed equally in these three layers. Together, these findings reveal that CSE and CBS are expressed in the retina, thereby supporting further studies to determine the role of H2S and these proteins in oxidative stress and apoptosis in retinal degenerative diseases.
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Shafabakhsh R, Aghadavod E, Ghayour‐Mobarhan M, Ferns G, Asemi Z. Role of histone modification and DNA methylation in signaling pathways involved in diabetic retinopathy. J Cell Physiol 2018; 234:7839-7846. [DOI: 10.1002/jcp.27844] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Accepted: 11/15/2018] [Indexed: 12/12/2022]
Affiliation(s)
- Rana Shafabakhsh
- Research Center for Biochemistry and Nutrition in Metabolic Diseases Kashan University of Medical Sciences Kashan Iran
| | - Esmat Aghadavod
- Research Center for Biochemistry and Nutrition in Metabolic Diseases Kashan University of Medical Sciences Kashan Iran
| | - Majid Ghayour‐Mobarhan
- Metabolic Syndrome Research Center School of Medicine, Mashhad University of Medical Sciences Mashhad Iran
| | - Gordon Ferns
- Division of Medical Education Brighton & Sussex Medical School Brighton UK
| | - Zatollah Asemi
- Research Center for Biochemistry and Nutrition in Metabolic Diseases Kashan University of Medical Sciences Kashan Iran
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Guo L, Normando EM, Shah PA, De Groef L, Cordeiro MF. Oculo-visual abnormalities in Parkinson's disease: Possible value as biomarkers. Mov Disord 2018; 33:1390-1406. [DOI: 10.1002/mds.27454] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Revised: 05/16/2018] [Accepted: 05/18/2018] [Indexed: 12/16/2022] Open
Affiliation(s)
- Li Guo
- Glaucoma and Retinal Degenerative Disease Research Group, Institute of Ophthalmology; University College London; London UK
| | - Eduardo M. Normando
- Glaucoma and Retinal Degenerative Disease Research Group, Institute of Ophthalmology; University College London; London UK
- Western Eye Hospital, Imperial College Healthcare National Health Service Trust; London UK
- Imperial College Ophthalmology Research Group, Department of Surgery and Cancer, Imperial College London; London UK
| | - Parth Arvind Shah
- Glaucoma and Retinal Degenerative Disease Research Group, Institute of Ophthalmology; University College London; London UK
| | - Lies De Groef
- Glaucoma and Retinal Degenerative Disease Research Group, Institute of Ophthalmology; University College London; London UK
- Neural Circuit Development and Regeneration Research Group, Department of Biology; University of Leuven; Leuven Belgium
| | - M. Francesca Cordeiro
- Glaucoma and Retinal Degenerative Disease Research Group, Institute of Ophthalmology; University College London; London UK
- Western Eye Hospital, Imperial College Healthcare National Health Service Trust; London UK
- Imperial College Ophthalmology Research Group, Department of Surgery and Cancer, Imperial College London; London UK
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Corso-Díaz X, Jaeger C, Chaitankar V, Swaroop A. Epigenetic control of gene regulation during development and disease: A view from the retina. Prog Retin Eye Res 2018; 65:1-27. [PMID: 29544768 PMCID: PMC6054546 DOI: 10.1016/j.preteyeres.2018.03.002] [Citation(s) in RCA: 80] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Revised: 02/01/2018] [Accepted: 03/08/2018] [Indexed: 12/20/2022]
Abstract
Complex biological processes, such as organogenesis and homeostasis, are stringently regulated by genetic programs that are fine-tuned by epigenetic factors to establish cell fates and/or to respond to the microenvironment. Gene regulatory networks that guide cell differentiation and function are modulated and stabilized by modifications to DNA, RNA and proteins. In this review, we focus on two key epigenetic changes - DNA methylation and histone modifications - and discuss their contribution to retinal development, aging and disease, especially in the context of age-related macular degeneration (AMD) and diabetic retinopathy. We highlight less-studied roles of DNA methylation and provide the RNA expression profiles of epigenetic enzymes in human and mouse retina in comparison to other tissues. We also review computational tools and emergent technologies to profile, analyze and integrate epigenetic information. We suggest implementation of editing tools and single-cell technologies to trace and perturb the epigenome for delineating its role in transcriptional regulation. Finally, we present our thoughts on exciting avenues for exploring epigenome in retinal metabolism, disease modeling, and regeneration.
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Affiliation(s)
- Ximena Corso-Díaz
- Neurobiology-Neurodegeneration & Repair Laboratory, National Eye Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Catherine Jaeger
- Neurobiology-Neurodegeneration & Repair Laboratory, National Eye Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Vijender Chaitankar
- Neurobiology-Neurodegeneration & Repair Laboratory, National Eye Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Anand Swaroop
- Neurobiology-Neurodegeneration & Repair Laboratory, National Eye Institute, National Institutes of Health, Bethesda, MD, 20892, USA.
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Aboelnour A, Van der Spuy J, Powner M, Jeffery G. Primate retinal cones express phosphorylated tau associated with neuronal degeneration yet survive in old age. Exp Eye Res 2017; 165:105-108. [PMID: 28974357 PMCID: PMC5725308 DOI: 10.1016/j.exer.2017.09.013] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Revised: 09/22/2017] [Accepted: 09/28/2017] [Indexed: 01/24/2023]
Abstract
Photoreceptor cells have high energy demands and suffer significantly with age. In aged rodents both rods and cones are lost, but in primates there is no evidence for aged cone loss, although their function declines. Here we ask if aged primate cones suffer from reduced function because of declining metabolic ability. Tau is a microtubule associated protein critical for mitochondrial function in neurons. Its phosphorylation is a feature of neuronal degeneration undermining respiration and mitochondrial dynamics. We show that total tau is widely distributed in the primate outer retina with little age-related change, being present in both rods and cones and their processes. However, all cones specifically accumulate phosphorylated tau, which was not seen in rods. The presence of this protein will likely undermine cone cell function. However, tau phosphorylation inhibits apoptosis. These data may explain why aged primate cones have reduced function but appear to be resistant to cell death. Consequently, therapies designed to remove phosphorylated tau may carry the risk of inducing cone photoreceptor cell death and further undermine ageing visual function.
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Affiliation(s)
- Asmaa Aboelnour
- Histology and Cytology Department, Faculty of Veterinary Medicine, Damanhour University, Egypt
| | | | - Michael Powner
- Department of Optometry and Visual Science, City University London, UK
| | - Glen Jeffery
- Institute of Ophthalmology, University College London, UK.
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Madendag Y, Acmaz G, Atas M, Sahin E, Tayyar AT, Madendag IÇ, Özdemir F, Senol V. The Effect of Oral Contraceptive Pills on the Macula, the Retinal Nerve Fiber Layer, and Choroidal Thickness. Med Sci Monit 2017; 23:5657-5661. [PMID: 29176540 PMCID: PMC5708262 DOI: 10.12659/msm.905183] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND The aim of this study was to evaluate the effect of oral contraceptive pills (OCP) on the macula, the retinal nerve fiber layer (RNFL), and choroidal thickness (CT). MATERIAL AND METHODS A total of 24 healthy women taking monophasic OCP (3 mg drospirenone and 0.03 mg ethinylestradiol) for contraception only for at least one year were compared with a control group of 24 healthy women who were not taking an OCP. Optical coherence tomography (OCT) was used to evaluate the posterior ocular segments, and measurements were taken in the follicular phase (day 3) of the cycle in all women. RESULTS No disparity in terms of age and body mass index between the groups was observed (p=0.436, p=0.538, respectively). In comparison of the macular region and CT between groups, we found that all variables except foveal center thickness and CT were significantly thinner in the OCP group. Nasal and temporal inferior parts of the RNFL and average RNFL were significantly slimmer in the study group versus the control group (p=0.013, p=0.018, and p<0.001, respectively). CONCLUSIONS OCP resulted in several structural changes in the posterior ocular segment. Thus, women using OCP for more than one year may have some eye problems. Therefore, it OCT should be performed for these women. Further clinical trials researching long-period effect of OCP on the eyes are needed.
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Affiliation(s)
- Yusuf Madendag
- Department of Obstetrics and Gynecology, Health Sciences University Kayseri Education and Research Hospital, Kayseri, Turkey
| | - Gokhan Acmaz
- Department of Obstetrics and Gynecology, Health Sciences University Kayseri Education and Research Hospital, Kayseri, Turkey
| | - Mustafa Atas
- Department of Ophthalmology, Health Sciences University Kayseri Education and Research Hospital, Kayseri, Turkey
| | - Erdem Sahin
- Department of Obstetrics and Gynecology, Health Sciences University Kayseri Education and Research Hospital, Kayseri, Turkey
| | - Ahter Tanay Tayyar
- Department of Obstetrics and Gynecology, Health Sciences University Zeynep Kamil Maternity and Children Training and Research Hospital, Istanbul, Turkey
| | - Ilknur Çol Madendag
- Department of Obstetrics and Gynecology, Health Sciences University Kayseri Education and Research Hospital, Kayseri, Turkey
| | - Fatma Özdemir
- Department of Obstetrics and Gynecology, Nevsehir Government Hospital, Nevsehir, Turkey
| | - Vesile Senol
- Department of Public Health, Erciyes University Faculty of Medicine, Kayseri, Turkey
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Hall H, Medina P, Cooper DA, Escobedo SE, Rounds J, Brennan KJ, Vincent C, Miura P, Doerge R, Weake VM. Transcriptome profiling of aging Drosophila photoreceptors reveals gene expression trends that correlate with visual senescence. BMC Genomics 2017; 18:894. [PMID: 29162050 PMCID: PMC5698953 DOI: 10.1186/s12864-017-4304-3] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2017] [Accepted: 11/14/2017] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Aging is associated with functional decline of neurons and increased incidence of both neurodegenerative and ocular disease. Photoreceptor neurons in Drosophila melanogaster provide a powerful model for studying the molecular changes involved in functional senescence of neurons since decreased visual behavior precedes retinal degeneration. Here, we sought to identify gene expression changes and the genomic features of differentially regulated genes in photoreceptors that contribute to visual senescence. RESULTS To identify gene expression changes that could lead to visual senescence, we characterized the aging transcriptome of Drosophila sensory neurons highly enriched for photoreceptors. We profiled the nuclear transcriptome of genetically-labeled photoreceptors over a 40 day time course and identified increased expression of genes involved in stress and DNA damage response, and decreased expression of genes required for neuronal function. We further show that combinations of promoter motifs robustly identify age-regulated genes, suggesting that transcription factors are important in driving expression changes in aging photoreceptors. However, long, highly expressed and heavily spliced genes are also more likely to be downregulated with age, indicating that other mechanisms could contribute to expression changes at these genes. Lastly, we identify that circular RNAs (circRNAs) strongly increase during aging in photoreceptors. CONCLUSIONS Overall, we identified changes in gene expression in aging Drosophila photoreceptors that could account for visual senescence. Further, we show that genomic features predict these age-related changes, suggesting potential mechanisms that could be targeted to slow the rate of age-associated visual decline.
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Affiliation(s)
- Hana Hall
- Department of Biochemistry, Purdue University, West Lafayette, IN, 47907, USA
| | - Patrick Medina
- Department of Statistics, Purdue University, West Lafayette, IN, 47907, USA
| | - Daphne A Cooper
- Department of Biology, University of Nevada, Reno, NV, 89557, USA
| | - Spencer E Escobedo
- Department of Biochemistry, Purdue University, West Lafayette, IN, 47907, USA
| | - Jeremiah Rounds
- Department of Statistics, Purdue University, West Lafayette, IN, 47907, USA
| | - Kaelan J Brennan
- Department of Biochemistry, Purdue University, West Lafayette, IN, 47907, USA
| | | | - Pedro Miura
- Department of Biology, University of Nevada, Reno, NV, 89557, USA
| | | | - Vikki M Weake
- Department of Biochemistry, Purdue University, West Lafayette, IN, 47907, USA. .,Purdue University Center for Cancer Research, Purdue University, West Lafayette, 47907, USA.
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Giménez M, Beersma D, Daan S, van der Pol B, Kanis M, van Norren D, Gordijn M. Melatonin and Sleep-Wake Rhythms before and after Ocular Lens Replacement in Elderly Humans. BIOLOGY 2016; 5:E12. [PMID: 26891336 PMCID: PMC4810169 DOI: 10.3390/biology5010012] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/11/2015] [Revised: 01/19/2016] [Accepted: 02/02/2016] [Indexed: 12/04/2022]
Abstract
Light of short wavelengths has been shown to play a key role in non-image forming responses. Due to aging, the ocular lens becomes more yellow reducing the transmission of short wavelengths in the elderly. In the present study, we make use of cataract surgery to investigate the effects of a relative increase of short wavelength transmission on melatonin- and sleep-wake rhythms (N = 14). We observed, on average, a delay of the sleep-wake and the nocturnal melatonin rhythms after cataract surgery. This delay is tentatively attributed to a relatively large increase of light transmittance in the evening hours more than an increase of the already relatively high light intensities found in the daytime. The later phase that we observed after cataract surgery (clear lens) as compared to the earlier phase observed before cataract (yellowish lens) is in agreement with the general later phase reported in the young (clear lens) population.
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Affiliation(s)
- Marina Giménez
- Department of Chronobiology, GeLifes, University of Groningen, Groningen 9747 AG, The Netherlands; (D.B.); (S.D.); (M.G.)
- Chrono@Work B.V., Groningen 9747 AT, The Netherlands
| | - Domien Beersma
- Department of Chronobiology, GeLifes, University of Groningen, Groningen 9747 AG, The Netherlands; (D.B.); (S.D.); (M.G.)
| | - Serge Daan
- Department of Chronobiology, GeLifes, University of Groningen, Groningen 9747 AG, The Netherlands; (D.B.); (S.D.); (M.G.)
| | - Bert van der Pol
- Department of Ophthalmology, University Medical Centre Groningen, Groningen 9713 GZ, The Netherlands;
| | - Martijn Kanis
- Department of Ophthalmology, University Medical Centre Utrecht, Utrecht 3584 CX, The Netherlands; (M.K.); (D.N.)
| | - Dick van Norren
- Department of Ophthalmology, University Medical Centre Utrecht, Utrecht 3584 CX, The Netherlands; (M.K.); (D.N.)
| | - Marijke Gordijn
- Department of Chronobiology, GeLifes, University of Groningen, Groningen 9747 AG, The Netherlands; (D.B.); (S.D.); (M.G.)
- Chrono@Work B.V., Groningen 9747 AT, The Netherlands
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Yang HJ, Ratnapriya R, Cogliati T, Kim JW, Swaroop A. Vision from next generation sequencing: multi-dimensional genome-wide analysis for producing gene regulatory networks underlying retinal development, aging and disease. Prog Retin Eye Res 2015; 46:1-30. [PMID: 25668385 PMCID: PMC4402139 DOI: 10.1016/j.preteyeres.2015.01.005] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2014] [Revised: 01/18/2015] [Accepted: 01/21/2015] [Indexed: 01/10/2023]
Abstract
Genomics and genetics have invaded all aspects of biology and medicine, opening uncharted territory for scientific exploration. The definition of "gene" itself has become ambiguous, and the central dogma is continuously being revised and expanded. Computational biology and computational medicine are no longer intellectual domains of the chosen few. Next generation sequencing (NGS) technology, together with novel methods of pattern recognition and network analyses, has revolutionized the way we think about fundamental biological mechanisms and cellular pathways. In this review, we discuss NGS-based genome-wide approaches that can provide deeper insights into retinal development, aging and disease pathogenesis. We first focus on gene regulatory networks (GRNs) that govern the differentiation of retinal photoreceptors and modulate adaptive response during aging. Then, we discuss NGS technology in the context of retinal disease and develop a vision for therapies based on network biology. We should emphasize that basic strategies for network construction and analyses can be transported to any tissue or cell type. We believe that specific and uniform guidelines are required for generation of genome, transcriptome and epigenome data to facilitate comparative analysis and integration of multi-dimensional data sets, and for constructing networks underlying complex biological processes. As cellular homeostasis and organismal survival are dependent on gene-gene and gene-environment interactions, we believe that network-based biology will provide the foundation for deciphering disease mechanisms and discovering novel drug targets for retinal neurodegenerative diseases.
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Affiliation(s)
- Hyun-Jin Yang
- Neurobiology-Neurodegeneration and Repair Laboratory, National Eye Institute, National Institutes of Health, 6 Center Drive, Bethesda, MD 20892-0610, USA
| | - Rinki Ratnapriya
- Neurobiology-Neurodegeneration and Repair Laboratory, National Eye Institute, National Institutes of Health, 6 Center Drive, Bethesda, MD 20892-0610, USA
| | - Tiziana Cogliati
- Neurobiology-Neurodegeneration and Repair Laboratory, National Eye Institute, National Institutes of Health, 6 Center Drive, Bethesda, MD 20892-0610, USA
| | - Jung-Woong Kim
- Neurobiology-Neurodegeneration and Repair Laboratory, National Eye Institute, National Institutes of Health, 6 Center Drive, Bethesda, MD 20892-0610, USA
| | - Anand Swaroop
- Neurobiology-Neurodegeneration and Repair Laboratory, National Eye Institute, National Institutes of Health, 6 Center Drive, Bethesda, MD 20892-0610, USA.
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Mohan A, Dabir S, Yadav NK, Kummelil M, Kumar RS, Shetty R. Normative database of retinal oximetry in Asian Indian eyes. PLoS One 2015; 10:e0126179. [PMID: 25923699 PMCID: PMC4414619 DOI: 10.1371/journal.pone.0126179] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2014] [Accepted: 03/30/2015] [Indexed: 11/18/2022] Open
Abstract
Objective To study the oxygen saturation profile in normal Asian Indian eyes. Design A cross sectional prospective study. Subjects Ninety eight consecutive patients presenting to our hospital with best corrected distance visual acuity (BCVA) of 20/20 and a normal ophthalmic examination were included in the study. Patients having any ocular or systemic disease were excluded from the study. Materials and Methods Oximetry was performed on all subjects with the Oxymap T1 retinal oximeter (Oxymap hf, Reykjavik, Iceland). Main Outcome Measures The images were analysed for oxygen saturation and diameter. Results The mean age was 33 years (Range: 18-63; SD: 12.4). The average arteriolar saturation was 90.3 ± 6.6% and the venous saturation was 56.9% ± 6.3. The average A-V (arterio-venous) difference was 33.2% ± 5.2. There was an increase in arteriolar (R2 = 0.264; p=0.001) and venous saturation (R2 = 0.151; p=0.001) with age. There was no significant change in the arterio-venous saturation difference (AVSD). The inferotemporal quadrant had the lowest saturations. Age correlated positively with ocular perfusion pressure (OPP)(R2 = 0.07; p=0.007). OPP correlated positively with global arteriolar saturation (R2=0.057, p=0.018). Conclusion This study provides the normative database for an Indian population and is comparable to previous studies. Age, vessel diameter and OPP were the significant factors that influenced the saturation. Arteriolar and venous saturations increased with age while the AVSD did not change significantly.
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Affiliation(s)
- Ashwin Mohan
- Narayana Nethralaya, Post Graduate Institute of Ophthalmology, Bangalore, India
| | - Supriya Dabir
- Narayana Nethralaya, Post Graduate Institute of Ophthalmology, Bangalore, India
- * E-mail:
| | - Naresh Kumar Yadav
- Narayana Nethralaya, Post Graduate Institute of Ophthalmology, Bangalore, India
| | - Matthew Kummelil
- Narayana Nethralaya, Post Graduate Institute of Ophthalmology, Bangalore, India
| | - Rajesh S. Kumar
- Narayana Nethralaya, Post Graduate Institute of Ophthalmology, Bangalore, India
| | - Rohit Shetty
- Narayana Nethralaya, Post Graduate Institute of Ophthalmology, Bangalore, India
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Reply. Retina 2015; 35:e16-8. [DOI: 10.1097/iae.0000000000000454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Correspondence. Retina 2015; 35:e16. [DOI: 10.1097/iae.0000000000000453] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Bora NS, Matta B, Lyzogubov VV, Bora PS. Relationship between the complement system, risk factors and prediction models in age-related macular degeneration. Mol Immunol 2014; 63:176-83. [PMID: 25074023 DOI: 10.1016/j.molimm.2014.07.012] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Accepted: 07/09/2014] [Indexed: 11/27/2022]
Abstract
Studies performed over the past decade in humans and experimental animals have been a major source of information and improved our understanding of how dysregulation of the complement system contributes to age-related macular degeneration (AMD) pathology. Drusen, the hall-mark of dry-type AMD are reported to be the by-product of complement mediated inflammatory processes. In wet AMD, unregulated complement activation results in increased production of angiogenic growth factors leading to choroidal neovascularization both in humans and in animal models. In this review article we have linked the complement system with modifiable and non-modifiable AMD risk factors as well as with prediction models of AMD. Understanding the association between the complement system, risk factors and prediction models will help improve our understanding of AMD pathology and management of this disease.
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Affiliation(s)
- Nalini S Bora
- Department of Ophthalmology, Jones Eye Institute, Pat and Willard Walker Eye Research Center, University of Arkansas for Medical Sciences, 4301 West Markham, Little Rock, AR 72205, USA.
| | - Bharati Matta
- Department of Ophthalmology, Jones Eye Institute, Pat and Willard Walker Eye Research Center, University of Arkansas for Medical Sciences, 4301 West Markham, Little Rock, AR 72205, USA
| | - Valeriy V Lyzogubov
- Department of Ophthalmology, Jones Eye Institute, Pat and Willard Walker Eye Research Center, University of Arkansas for Medical Sciences, 4301 West Markham, Little Rock, AR 72205, USA
| | - Puran S Bora
- Department of Ophthalmology, Jones Eye Institute, Pat and Willard Walker Eye Research Center, University of Arkansas for Medical Sciences, 4301 West Markham, Little Rock, AR 72205, USA
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Abstract
PURPOSE To determine normal retinal oxygen saturation (SO2) values measured with retinal oximetry in a multiethnic group of healthy subjects and to evaluate the association of retinal SO2 with demographic and clinical parameters. METHODS Retinal oximetry was performed in both eyes of 61 normal healthy subjects. Global and quadrant venous (SvO2) and arterial oxygen saturation (SaO2), arteriovenous difference in SO2, and venular and arteriolar width were measured. The association of SO2 parameters with age, gender, ethnicity, refraction, iris color, history of controlled systemic hypertension, and smoking was analyzed. RESULTS Average SvO2 and SaO2 were 55.3 ± 7.1% and 90.4 ± 4.3%, respectively. All average measurements were comparable in both eyes, both genders, and among ethnic groups. Inferonasal quadrant SaO2 was higher in Asians. Age was associated with decreased SvO2 (β = -0.19; P = 0.001) and SaO2 (β = -0.11; P = 0.003). History of controlled systemic hypertension was associated with an increase in arteriovenous difference in SO2 (β = 3.99; P = 0.013). CONCLUSION This is the first description of retinal SO2 in healthy, multiethnic subjects. Aging decreases SvO2 and SaO2 and should be accounted for when interpreting retinal oximetry measurements. Other demographic and clinical parameters studied did not seem to significantly influence retinal SO2 measurements.
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Rutar M, Valter K, Natoli R, Provis JM. Synthesis and propagation of complement C3 by microglia/monocytes in the aging retina. PLoS One 2014; 9:e93343. [PMID: 24705166 PMCID: PMC3976274 DOI: 10.1371/journal.pone.0093343] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2013] [Accepted: 03/05/2014] [Indexed: 12/16/2022] Open
Abstract
INTRODUCTION Complement activation is thought to contribute to the pathogenesis of age-related macular degeneration (AMD), which may be mediated in part by para-inflammatory processes. We aimed to investigate the expression and localization of C3, a crucial component of the complement system, in the retina during the course of aging. METHODS SD rats were born and reared in low-light conditions, and euthanized at post-natal (P) days 100, 450, or 750. Expression of C3, IBA1, and Ccl- and Cxcl- chemokines was assessed by qPCR, and in situ hybridization. Thickness of the ONL was assessed in retinal sections as a measure of photoreceptor loss, and counts were made of C3-expressing monocytes. RESULTS C3 expression increased significantly at P750, and correlated with thinning of the ONL, at P750, and up-regulation of GFAP. In situ hybridization showed that C3 was expressed by microglia/monocytes, mainly from within the retinal vasculature, and occasionally the ONL. The number of C3-expressing microglia increased significantly by P750, and coincided spatiotemporally with thinning of the ONL, and up-regulation of Ccl- and Cxcl- chemokines. CONCLUSIONS Our data suggest that recruited microglia/monocytes contribute to activation of complement in the aging retina, through local expression of C3 mRNA. C3 expression coincides with age-related thinning of the ONL at P750, although it is unclear whether the C3-expressing monocytes are a cause or consequence. These findings provide evidence of activation of complement during natural aging, and may have relevance to cellular events underling the pathogenesis of age-related retinal diseases.
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Affiliation(s)
- Matt Rutar
- The John Curtin School of Medical Research, The Australian National University (ANU), Canberra, Australian Capital Territory, Australia
- * E-mail:
| | - Krisztina Valter
- The John Curtin School of Medical Research, The Australian National University (ANU), Canberra, Australian Capital Territory, Australia
- ANU Medical School, The Australian National University (ANU), Canberra, Australian Capital Territory, Australia
| | - Riccardo Natoli
- The John Curtin School of Medical Research, The Australian National University (ANU), Canberra, Australian Capital Territory, Australia
- ANU Medical School, The Australian National University (ANU), Canberra, Australian Capital Territory, Australia
| | - Jan M. Provis
- The John Curtin School of Medical Research, The Australian National University (ANU), Canberra, Australian Capital Territory, Australia
- ANU Medical School, The Australian National University (ANU), Canberra, Australian Capital Territory, Australia
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Gkotsi D, Begum R, Salt T, Lascaratos G, Hogg C, Chau KY, Schapira AHV, Jeffery G. Recharging mitochondrial batteries in old eyes. Near infra-red increases ATP. Exp Eye Res 2014; 122:50-3. [PMID: 24631333 DOI: 10.1016/j.exer.2014.02.023] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2013] [Revised: 02/19/2014] [Accepted: 02/25/2014] [Indexed: 10/25/2022]
Abstract
Progressive accumulation of age related mitochondrial DNA mutations reduce ATP production and increase reactive oxygen species output, leading to oxidative stress, inflammation and degradation. The pace of this is linked to metabolic demand. The retina has the greatest metabolic demand and mitochondrial density in the body and displays progressive age related inflammation and marked cell loss. Near infra-red (670 nm) is thought to be absorbed by cytochrome c oxidase (COX), a key element in mitochondrial respiration and it has been demonstrated that it improves mitochondrial membrane potentials in aged eyes. It also significantly reduces the impact of experimental pathology and ameliorates age related retinal inflammation. We show ATP decline with ageing in mouse retina and brain. Also, in these tissues that ATP is significantly increased by 670 nm exposure in old mice. In the retina this was associated with increased COX and reduced acrolein expression. Acrolein, being a free radical marker of retinal oxidative stress, is up regulated in Alzheimer's and retinal degeneration. This is the first demonstration of ATP manipulation in vivo and may provide a simple non-invasive route to combating age related tissue decline.
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Affiliation(s)
- Despoina Gkotsi
- Institute of Ophthalmology, University College London, 11-43 Bath Street, London EC1V 9EL, UK
| | - Rana Begum
- Institute of Ophthalmology, University College London, 11-43 Bath Street, London EC1V 9EL, UK
| | - Thomas Salt
- Institute of Ophthalmology, University College London, 11-43 Bath Street, London EC1V 9EL, UK
| | | | | | - Kai-Yin Chau
- Institute of Neurology, University College London, UK
| | | | - Glen Jeffery
- Institute of Ophthalmology, University College London, 11-43 Bath Street, London EC1V 9EL, UK.
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Peng CH, Cherng JY, Chiou GY, Chen YC, Chien CH, Kao CL, Chang YL, Chien Y, Chen LK, Liu JH, Chen SJ, Chiou SH. Delivery of Oct4 and SirT1 with cationic polyurethanes-short branch PEI to aged retinal pigment epithelium. Biomaterials 2011; 32:9077-88. [DOI: 10.1016/j.biomaterials.2011.08.008] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2011] [Accepted: 08/04/2011] [Indexed: 01/30/2023]
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Lei Y, Garrahan N, Hermann B, Fautsch MP, Johnson DH, Hernandez MR, Boulton M, Morgan JE. Transretinal degeneration in ageing human retina: a multiphoton microscopy analysis. Br J Ophthalmol 2010; 95:727-30. [PMID: 21183516 DOI: 10.1136/bjo.2010.180869] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
AIM Retinal cell remodelling has been reported as a consistent feature of ageing. However, the degree to which this results in transretinal degeneration is unclear. To address this, the authors used multiphoton microscopy to quantify retinal degeneration in post-mortem human eyes of two age groups. METHODS Retinas from six young subjects (18-33 years old) and six older subjects (74-90 years old) were prepared as wholemount preparations. All retinas were stained with 4,6-diamidino-2-phenylindole and imaged by multiphoton confocal microscopy to quantify neuron densities in the retinal ganglion cell layer (RGCL), inner nuclear layer (INL) and outer nuclear layer (ONL). Neurons were counted using automated cell identification algorithms. All retinas were imaged hydrated to minimise tissue artefacts. RESULTS In both groups, 56% of the area within the central 4 mm eccentricity and 27% of the area with eccentricity between 4 mm and 7 mm were imaged. Compared with young subjects, the peak RGCL neuron loss in the aged subjects (25.5%) was at 1 mm eccentricity. INL and ONL neuron densities significantly decreased at 1-2 mm eccentricity (8.7%) and 0.5-4 mm eccentricity (15.6%) respectively (P <0.05). The reduction in neuron density in the INL corresponded, spatially, to the region with the greatest neuron loss in the RGCL and ONL. CONCLUSIONS This is the first study to correlate neurodegeneration in different populations of cells in the ageing retinas. These data confirm that the greatest neuronal loss occurs in the RGCL and ONL in human ageing retinas, whereas the INL is relatively preserved.
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Affiliation(s)
- Y Lei
- Optometry and Vision Sciences, Cardiff University, Cardiff, UK
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Parapuram SK, Cojocaru RI, Chang JR, Khanna R, Brooks M, Othman M, Zareparsi S, Khan NW, Gotoh N, Cogliati T, Swaroop A. Distinct signature of altered homeostasis in aging rod photoreceptors: implications for retinal diseases. PLoS One 2010; 5:e13885. [PMID: 21079736 PMCID: PMC2975639 DOI: 10.1371/journal.pone.0013885] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2010] [Accepted: 10/15/2010] [Indexed: 12/04/2022] Open
Abstract
Background Advanced age contributes to clinical manifestations of many retinopathies and represents a major risk factor for age-related macular degeneration, a leading cause of visual impairment and blindness in the elderly. Rod photoreceptors are especially vulnerable to genetic defects and changes in microenvironment, and are among the first neurons to die in normal aging and in many retinal degenerative diseases. The molecular mechanisms underlying rod photoreceptor vulnerability and potential biomarkers of the aging process in this highly specialized cell type are unknown. Methodology/Principal Findings To discover aging-associated adaptations that may influence rod function, we have generated gene expression profiles of purified rod photoreceptors from mouse retina at young adult to early stages of aging (1.5, 5, and 12 month old mice). We identified 375 genes that showed differential expression in rods from 5 and 12 month old mouse retina compared to that of 1.5 month old retina. Quantitative RT-PCR experiments validated expression change for a majority of the 25 genes that were examined. Macroanalysis of differentially expressed genes using gene class testing and protein interaction networks revealed overrepresentation of cellular pathways that are potentially photoreceptor-specific (angiogenesis and lipid/retinoid metabolism), in addition to age-related pathways previously described in several tissue types (oxidative phosphorylation, stress and immune response). Conclusions/Significance Our study suggests a progressive shift in cellular homeostasis that may underlie aging-associated functional decline in rod photoreceptors and contribute to a more permissive state for pathological processes involved in retinal diseases.
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Affiliation(s)
- Sunil K. Parapuram
- Department of Ophthalmology and Visual Sciences, Kellogg Eye Center, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Radu I. Cojocaru
- Department of Ophthalmology and Visual Sciences, Kellogg Eye Center, University of Michigan, Ann Arbor, Michigan, United States of America
- Neurobiology Neurodegeneration & Repair Laboratory, National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Jessica R. Chang
- Neurobiology Neurodegeneration & Repair Laboratory, National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States of America
- Howard Hughes Medical Institute-National Institutes of Health Research Scholars Program, Bethesda, Maryland, United States of America
| | - Ritu Khanna
- Department of Ophthalmology and Visual Sciences, Kellogg Eye Center, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Matthew Brooks
- Department of Ophthalmology and Visual Sciences, Kellogg Eye Center, University of Michigan, Ann Arbor, Michigan, United States of America
- Neurobiology Neurodegeneration & Repair Laboratory, National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Mohammad Othman
- Department of Ophthalmology and Visual Sciences, Kellogg Eye Center, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Sepideh Zareparsi
- Department of Ophthalmology and Visual Sciences, Kellogg Eye Center, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Naheed W. Khan
- Department of Ophthalmology and Visual Sciences, Kellogg Eye Center, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Norimoto Gotoh
- Neurobiology Neurodegeneration & Repair Laboratory, National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Tiziana Cogliati
- Neurobiology Neurodegeneration & Repair Laboratory, National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Anand Swaroop
- Department of Ophthalmology and Visual Sciences, Kellogg Eye Center, University of Michigan, Ann Arbor, Michigan, United States of America
- Neurobiology Neurodegeneration & Repair Laboratory, National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States of America
- * E-mail:
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Abstract
Even in healthy individuals, aging leads to deterioration in visual acuity, contrast sensitivity, visual field, and dark adaptation. Little is known about the neural mechanisms that drive the age-related changes of the retina and, more specifically, photoreceptors. According to one hypothesis, the age-related deterioration in rod function is due to the limited availability of 11-cis-retinal for rod pigment formation. To determine how aging affects rod photoreceptors and to test the retinoid-deficiency hypothesis, we compared the morphological and functional properties of rods of adult and aged B6D2F1/J mice. We found that the number of rods and the length of their outer segments were significantly reduced in 2.5-year-old mice compared with 4-month-old animals. Aging also resulted in a twofold reduction in the total level of opsin in the retina. Behavioral tests revealed that scotopic visual acuity and contrast sensitivity were decreased by twofold in aged mice, and rod ERG recordings demonstrated reduced amplitudes of both a- and b-waves. Sensitivity of aged rods determined from single-cell recordings was also decreased by 1.5-fold, corresponding to not more than 1% free opsin in these photoreceptors, and kinetic parameters of dim flash response were not altered. Notably, the rate of rod dark adaptation was unaffected by age. Thus, our results argue against age-related deficiency of 11-cis-retinal in the B6D2F1/J mouse rod visual cycle. Surprisingly, the level of cellular dark noise was increased in aged rods, providing an alternative mechanism for their desensitization.
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Wexler A, Sand T, Elsås TB. Macular thickness measurements in healthy Norwegian volunteers: an optical coherence tomography study. BMC Ophthalmol 2010; 10:13. [PMID: 20465801 PMCID: PMC2885325 DOI: 10.1186/1471-2415-10-13] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2009] [Accepted: 05/13/2010] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Ethnic, intersubject, interoperator and intermachine differences in measured macular thickness seem to exist. Our purpose was to collect normative macular thickness data in Norwegians and to evaluate the association between macular thickness and age, gender, parity, and contraception status. METHODS Retinal thickness was measured by Stratus Optical Coherence Tomography in healthy subjects. Mean macular thickness (MMT) was analyzed by repeated measures ANOVA with three dependent regional MMT-variables for interaction with age, gender, parity and oral contraception use. Exploratory correlation with age by the Pearson correlation test, both before and after stratification by gender was performed. Differences in MMT between older and younger subjects, between oral contraception users and non-users, as well as parous and nulliparous women were studied by post-hoc Student's t-tests. RESULTS Central MMT in Norwegians was similar to values earlier reported in whites. MMT in central areas of 1 and 2.25 mm in diameter were higher in males than in females. In younger subjects (< or =43 years) differences in MMT between genders were larger than in the mixed age group, whereas in older subjects (>43 years) the small differences did not reach the set significance level. No differences were found in minimal foveolar thickness (MMFT) between the genders in any age group.Mean foveal thickness (1 mm in diameter) was positively associated with age in females (r = 0.28, p = 0.03). MMFT was positively associated with age in all groups and reached significance both in females and in mixed gender group (r = 0.20, p = 0.041 and r = 0.26, p = 0.044 respectively).Mean foveal thickness and MMFT were significantly higher in parous than in nulliparous women, and age-adjusted ANOVA for MMFT revealed a borderline effect of parity. CONCLUSIONS Age and gender should be taken into consideration when establishing normal ranges for MMT in younger subjects. The gender difference in retinal thickness in young, but not older adults suggests a gonadal hormonal influence. The possible association between parity and retinal structure and its clinical relevance, should be studied further.
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Affiliation(s)
- Alexandra Wexler
- Department of Ophthalmology, St. Olavs University Hospital, Trondheim, Norway.
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Methionine sulfoxide reductase B2 is highly expressed in the retina and protects retinal pigmented epithelium cells from oxidative damage. Exp Eye Res 2009; 90:420-8. [PMID: 20026324 DOI: 10.1016/j.exer.2009.12.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2009] [Revised: 12/04/2009] [Accepted: 12/08/2009] [Indexed: 12/19/2022]
Abstract
Methionine sulfoxide reductase B2 (MSRB2) is a mitochondrial enzyme that converts methionine sulfoxide (R) enantiomer back to methionine. This enzyme is suspected of functioning to protect mitochondrial proteins from oxidative damage. In this study we report that the retina is one of the human tissues with highest levels of MSRB2 mRNA expression. Other tissues with high expression were heart, kidney and skeletal muscle. Overexpression of an MSRB2-GFP fusion protein increased the MSR enzymatic activity three-fold in stably transfected cultured RPE cells. This overexpression augmented the resistance of these cells to the toxicity induced by 7-ketocholesterol, tert-butyl hydroperoxide and all-trans retinoic acid. By contrast, knockdown of MSRB2 by a miRNA in stably transfected cells did not convey increased sensitivity to the oxidative stress. In the monkey retina MSRB2 localized to the ganglion cell layer (GLC), the outer plexiform layer (OPL) and the retinal pigment epithelium (RPE). MSRB2 expression is most pronounced in the OPL of the macula and foveal regions suggesting an association with the cone synaptic mitochondria. Our data suggests that MSRB2 plays an important function in protecting cones from multiple type of oxidative stress and may be critical in preserving central vision.
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Claudepierre T, Paques M, Simonutti M, Buard I, Sahel J, Maue RA, Picaud S, Pfrieger FW. Lack of Niemann-Pick type C1 induces age-related degeneration in the mouse retina. Mol Cell Neurosci 2009; 43:164-76. [PMID: 19883762 DOI: 10.1016/j.mcn.2009.10.007] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2009] [Accepted: 10/17/2009] [Indexed: 11/26/2022] Open
Abstract
Niemann-Pick type C (NPC) disease is an inherited lysosomal storage disease and caused by mutations in Npc1 or Npc2, which mediate cooperatively the egress of cholesterol from lysosomes. The disease entails progressive neurodegeneration, whose cause is poorly understood. Here, we report that Npc1 is distributed in distinct layers of the mouse retina and that its deficiency causes striking retinal degeneration in 2-month-old mice with signs of age-related maculopathies. This includes impaired visual function, accumulation of lipofuscin in the retinal pigment epithelium layer, degeneration of photoreceptor outer segments, disruption of synaptic layers and an increase in autophagy markers in the ganglion cell layer. Moreover, the lack of Npc1 results in the upregulation of proteins that mediate cellular cholesterol release in the retina. Our findings suggest that Npc1 is required for normal retinal function and that its absence may serve as model to study age-related degeneration of the retina.
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Affiliation(s)
- Thomas Claudepierre
- CNRS UPR 3212, University of Strasbourg, Institute of Cellular and Integrative Neurosciences (INCI), 5, rue Blaise Pascal, F-67084 Strasbourg, France
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Swaroop A, Chew EY, Rickman CB, Abecasis GR. Unraveling a multifactorial late-onset disease: from genetic susceptibility to disease mechanisms for age-related macular degeneration. Annu Rev Genomics Hum Genet 2009; 10:19-43. [PMID: 19405847 PMCID: PMC3469316 DOI: 10.1146/annurev.genom.9.081307.164350] [Citation(s) in RCA: 217] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Aging-associated neurodegenerative diseases significantly influence the quality of life of affected individuals. Genetic approaches, combined with genomic technology, have provided powerful insights into common late-onset diseases, such as age-related macular degeneration (AMD). Here, we discuss current findings on the genetics of AMD to highlight areas of rapid progress and new challenges. We also attempt to integrate available genetic and biochemical data with cellular pathways involved in aging to formulate an integrated model of AMD pathogenesis.
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Affiliation(s)
- Anand Swaroop
- Neurobiology-Neurodegeneration & Repair Laboratory (N-NRL), National Eye Institute, National Institutes of Health, Bethesda, Maryland, 20892, USA.
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Abstract
Human head movement control can be considered as part of the oculomotor system since the control of gaze involves coordination of the eyes and head. Humans show a remarkable degree of flexibility in eye-head coordination strategies, nonetheless an individual will often demonstrate stereotypical patterns of eye-head behaviour for a given visual task. This review examines eye-head coordination in laboratory-based visual tasks, such as saccadic gaze shifts and combined eye-head pursuit, and in common tasks in daily life, such as reading. The effect of the aging process on eye-head coordination is then reviewed from infancy through to senescence. Consideration is also given to how pathology can affect eye-head coordination from the lowest through to the highest levels of oculomotor control, comparing conditions as diverse as eye movement restrictions and schizophrenia. Given the adaptability of the eye-head system we postulate that this flexible system is under the control of the frontal cortical regions, which assist in planning, coordinating and executing behaviour. We provide evidence for this based on changes in eye-head coordination dependant on the context and expectation of presented visual stimuli, as well as from changes in eye-head coordination caused by frontal lobe dysfunction.
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Affiliation(s)
- Frank Antony Proudlock
- Ophthalmology Group, RKCSB, Leicester Royal Infirmary, University Hospitals of Leicester, University of Leicester, Leicester, UK.
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Changes in growth factor expression in normal aging of the rat retina. Exp Eye Res 2007; 85:817-24. [PMID: 17936752 DOI: 10.1016/j.exer.2007.08.017] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2007] [Revised: 08/01/2007] [Accepted: 08/14/2007] [Indexed: 01/20/2023]
Abstract
Although much is known about the growth factor changes in ocular tissues during various diseases, little is known about normal aging of the retina. In order to further understand normal aging in the retina, we characterized age-related changes of growth factor expression in three different ages of rat retina. Real time PCR and protein analysis was conducted to investigate steady state mRNA expression and protein levels of VEGF, VEGFR2, PEDF, Ang-1, Tie-2, EphB4 and ephrinB2 in the retina of 8-, 22-, and 32-month-old Brown Norway X Fischer 344 F1 hybrid rats. An increase of VEGF protein levels was found at 32months compared to 8 and 22months of age. VEGFR2 protein was found to be increased at 22 and 32months compared to 8months. PEDF protein levels were reduced at 22 and 32months. Tie-2 levels were found to be significantly decreased by 32months compared to 8months of age, while ephrinB2 was found to be significantly lower at both 22 and 32months compared to 8months of age. The increases found in VEGF and its receptor VEGFR2, with the simultaneous decrease of PEDF protein levels, may stimulate an environment that is well suited for neovascularization in the normal aging retina. Overall, these results suggest that normal aging produces substantial changes in gene expression and protein levels.
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Kerber KA, Ishiyama GP, Baloh RW. A longitudinal study of oculomotor function in normal older people. Neurobiol Aging 2006; 27:1346-53. [PMID: 16122840 DOI: 10.1016/j.neurobiolaging.2005.07.009] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2005] [Revised: 06/28/2005] [Accepted: 07/06/2005] [Indexed: 11/25/2022]
Abstract
Cross-sectional studies have found declines in most measures of oculomotor function in older subjects compared to young controls, but no prior study has followed the same subjects over time. We measured saccade peak velocity, saccade delay time, smooth pursuit, optokinetic nystagmus (OKN), visual-vestibular-ocular-reflex (VVOR), fixation suppression of the vestibulo-ocular reflex (VOR-fix), and the vestibulo-ocular reflex in 53 subjects (older than 75 years) able to complete at least 9 yearly evaluations. In addition at each visit all patients underwent a complete history and examination, a gait and balance assessment, mini-mental status evaluation, and visual acuity testing. A subset of subjects completed 12 yearly evaluations (14 patients). Despite significant declines of most variables over time, smooth pursuit gain and saccade peak velocity remained stable during the duration of the study both in the 9-year group and the patients completing 12 years. Decline in OKN, VVOR, and VOR were significantly correlated (P<0.001) with decline in the Tinetti gait and balance score, even after controlling for age. In normal healthy older subjects, smooth pursuit and saccade peak velocity are relatively maintained while OKN, VVOR, and VOR function decline. The significant correlation between decline in oculomotor measures and gait and balance measures (even after controlling for age) suggests a common mechanism for the decline in both measures.
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Affiliation(s)
- Kevin A Kerber
- Department of Neurology, Reed Neurological Research Center, 710 Westwood Plaza, Box 951769, UCLA School of Medicine, Los Angeles, CA, USA
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Liets LC, Eliasieh K, van der List DA, Chalupa LM. Dendrites of rod bipolar cells sprout in normal aging retina. Proc Natl Acad Sci U S A 2006; 103:12156-60. [PMID: 16880381 PMCID: PMC1524926 DOI: 10.1073/pnas.0605211103] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The aging nervous system is known to manifest a variety of degenerative and regressive events. Here we report the unexpected growth of dendrites in the retinas of normal old mice. The dendrites of many rod bipolar cells in aging mice were observed to extend well beyond their normal strata within the outer plexiform layer to innervate the outer nuclear layer where they appeared to form contacts with the spherules of rod photoreceptors. Such dendritic sprouting increased with age and was evident at all retinal eccentricities. These results provide evidence of retinal plasticity associated with normal aging.
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Affiliation(s)
| | | | | | - Leo M. Chalupa
- *Section of Neurobiology, Physiology, and Behavior and
- Department of Ophthalmology and Vision Science, School of Medicine, University of California, Davis, CA 95616
- To whom correspondence should be addressed at:
Section of Neurobiology, Physiology, and Behavior, University of California, One Shields Avenue, Davis, CA 95616. E-mail:
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Lee J, Gordiyenko N, Marchetti M, Tserentsoodol N, Sagher D, Alam S, Weissbach H, Kantorow M, Rodriguez I. Gene structure, localization and role in oxidative stress of methionine sulfoxide reductase A (MSRA) in the monkey retina. Exp Eye Res 2005; 82:816-27. [PMID: 16364291 PMCID: PMC2825745 DOI: 10.1016/j.exer.2005.10.003] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2005] [Revised: 10/03/2005] [Accepted: 10/06/2005] [Indexed: 12/29/2022]
Abstract
MSRA (EC 1.8.4.6) is a member of the methionine sulfoxide reductase family that can reduce methionine sulfoxide (MetO) in proteins. This repair function has been shown to protect cells against oxidative damage. In this study we have assembled the complete gene structure of msrA and identified the presence of two distinct putative promoters that generate three different transcripts. These transcripts were cloned by 5'RACE and code for three MSRA isoforms with different N-termini. The different forms of MSRA target to distinct intracellular regions. The main MSRA transcript (msrA1) had been previously shown to target the mitochondria. MsrA2 and 3 originate from a second promoter and target the cytosol and nuclei. In the monkey retina msrA message was detected mainly in the macular RPE-choroid region while its activity was measured mainly in the soluble fractions of fractionated neural retina and RPE-choroid. The MSRA protein is found throughout the retina but is especially abundant at the photoreceptor synapses, ganglion and Müller cells. Interestingly, MSRA was not detected in the mitochondria of the photoreceptor inner segments. The RPE in the peripheral retina shows very low levels of expression but the RPE in the macular region is strongly labeled. Targeted silencing of msrA message rendered cultured RPE cells more sensitive to oxidative damage suggesting a role for MSRA in RPE protection against oxidative stress. Collectively these data suggest MSRA may play an important role in protecting macular RPE from oxidative damage.
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Affiliation(s)
- J.W. Lee
- Lab of Retinal Cell and Molecular Biology, Mechanisms of Retinal Diseases Section, National Eye Institute, NIH, 7 Memorial drive MSC 0706, Bethesda, MD 20892, USA
| | - N.V. Gordiyenko
- Lab of Retinal Cell and Molecular Biology, Mechanisms of Retinal Diseases Section, National Eye Institute, NIH, 7 Memorial drive MSC 0706, Bethesda, MD 20892, USA
| | - M. Marchetti
- Department of Biomedical Science, Florida Atlantic University, Boca Raton, FL 33437, USA
| | - N. Tserentsoodol
- Lab of Retinal Cell and Molecular Biology, Mechanisms of Retinal Diseases Section, National Eye Institute, NIH, 7 Memorial drive MSC 0706, Bethesda, MD 20892, USA
| | - D. Sagher
- Center for Molecular Biology and Biotechnology, Florida Atlantic University, Boca Raton, FL 33437, USA
| | - S. Alam
- Lab of Retinal Cell and Molecular Biology, Mechanisms of Retinal Diseases Section, National Eye Institute, NIH, 7 Memorial drive MSC 0706, Bethesda, MD 20892, USA
| | - H. Weissbach
- Center for Molecular Biology and Biotechnology, Florida Atlantic University, Boca Raton, FL 33437, USA
| | - M. Kantorow
- Department of Biomedical Science, Florida Atlantic University, Boca Raton, FL 33437, USA
| | - I.R. Rodriguez
- Lab of Retinal Cell and Molecular Biology, Mechanisms of Retinal Diseases Section, National Eye Institute, NIH, 7 Memorial drive MSC 0706, Bethesda, MD 20892, USA
- Corresponding author. Ignacio R. Rodriguez, National Eye Institute, NIH, Mechanisms of Retinal Diseases Section, 7 Memorial Drive, MSC0706, Bldg. 7 Rm. 302, Bethesda, MD 20892, USA (I.R. Rodriguez)
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Abstract
AIM To study the effect of aging retina on the multifocal electroretinogram (mfERG). METHODS A total of 18 young subjects (age 18-24 years) and 36 elderly subjects (aged 60-85 years) with intraocular lenses (IOLs) were recruited for this study. No subjects had significant eye diseases or media opacities. mfERG was measured in standard conditions using the VERIS system (version 4.1). There were three groups of 18 subjects: (1) 18-25 years, (2) 60-70 years, and (3) 75-85 years. mfERG responses were grouped into central, paracentral, and peripheral regions for analysis. The N1 amplitude, P1 amplitude, N1 latency, and P1 latency of the first-order responses were analysed. RESULTS Age had no effect on P1 latency, N1 amplitude, and P1 amplitude; however, N1 latencies from central to peripheral regions were significantly longer for group 3 than for group 1. CONCLUSIONS This study suggests that measured age-related decreases in mfERG responses are due to optical factors (decrease in retinal light levels, scatter) before the age of 70 years, but neural factors significantly affect mfERG topography after the age of 70 years.
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Affiliation(s)
- W-K Tam
- Department of Optometry and Radiography, The Hong Kong Polytechnic University, Hong Kong
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