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Haddad M, Khazali H, Janahmadi M, Ghanbarian H. The differential effects of blocking retinal orexin receptors on the expression of retinal c-fos and hypothalamic Vip, PACAP, Bmal1, and c-fos in Male Wistar Rats. Exp Eye Res 2024; 244:109943. [PMID: 38797259 DOI: 10.1016/j.exer.2024.109943] [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: 01/16/2024] [Revised: 05/18/2024] [Accepted: 05/23/2024] [Indexed: 05/29/2024]
Abstract
Orexin A and B (OXA and OXB) and their receptors are expressed in the majority of retinal neurons in humans, rats, and mice. Orexins modulate signal transmission between the different layers of the retina. The suprachiasmatic nucleus (SCN) and the retina are central and peripheral components of the body's biological clocks; respectively. The SCN receives photic information from the retina through the retinohypothalamic tract (RHT) to synchronize bodily functions with environmental changes. In present study, we aimed to investigate the impact of inhibiting retinal orexin receptors on the expression of retinal Bmal1 and c-fos, as well as hypothalamic c-fos, Bmal1, Vip, and PACAP at four different time-points (Zeitgeber time; ZT 3, 6, 11, and ZT-0). The intravitreal injection (IVI) of OX1R antagonist (SB-334867) and OX2R antagonist (JNJ-10397049) significantly up-regulated c-fos expression in the retina. Additionally, compared to the control group, the combined injection of SB-334867 and JNJ-10397049 showed a greater increase in retinal expression of this gene. Moreover, the expression of hypothalamic Vip and PACAP was significantly up-regulated in both the SB-334867 and JNJ-10397049 groups. In contrast, the expression of Bmal1 was down-regulated. Furthermore, the expression of hypothalamic c-fos was down-regulated in all groups treated with SB-334867 and JNJ-10397049. Additionally, the study demonstrated that blocking these receptors in the retina resulted in alterations in circadian rhythm parameters such as mesor, amplitude, and acrophase. Finally, it affected the phase of gene expression rhythms in both the retina and hypothalamus, as identified through cosinor analysis and the zero-amplitude test. This study represents the initial exploration of how retinal orexin receptors influence expression of rhythmic genes in the retina and hypothalamus. These findings could provide new insights into how the retina regulates the circadian rhythm in both regions and illuminate the role of the orexinergic system expression within the retina.
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Affiliation(s)
- Muhammad Haddad
- Department of Zoology, Faculty of Sciences, Aleppo University, Aleppo, Syria; Department of Animal Sciences and Marine Biology, Faculty of Life Sciences and Biotechnology, Shahid Beheshti University, Tehran, Iran.
| | - Homayoun Khazali
- Department of Animal Sciences and Marine Biology, Faculty of Life Sciences and Biotechnology, Shahid Beheshti University, Tehran, Iran.
| | - Mahyar Janahmadi
- Department of Physiology and Neuroscience, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Hossein Ghanbarian
- Department of Medical Biotechnology, School of Advanced Technologies in Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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2
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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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3
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Rusciano D, Russo C. The Therapeutic Trip of Melatonin Eye Drops: From the Ocular Surface to the Retina. Pharmaceuticals (Basel) 2024; 17:441. [PMID: 38675402 PMCID: PMC11054783 DOI: 10.3390/ph17040441] [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: 03/04/2024] [Revised: 03/18/2024] [Accepted: 03/27/2024] [Indexed: 04/28/2024] Open
Abstract
Melatonin is a ubiquitous molecule found in living organisms, ranging from bacteria to plants and mammals. It possesses various properties, partly due to its robust antioxidant nature and partly owed to its specific interaction with melatonin receptors present in almost all tissues. Melatonin regulates different physiological functions and contributes to the homeostasis of the entire organism. In the human eye, a small amount of melatonin is also present, produced by cells in the anterior segment and the posterior pole, including the retina. In the eye, melatonin may provide antioxidant protection along with regulating physiological functions of ocular tissues, including intraocular pressure (IOP). Therefore, it is conceivable that the exogenous topical administration of sufficiently high amounts of melatonin to the eye could be beneficial in several instances: for the treatment of eye pathologies like glaucoma, due to the IOP-lowering and neuroprotection effects of melatonin; for the prevention of other dysfunctions, such as dry eye and refractive defects (cataract and myopia) mainly due to its antioxidant properties; for diabetic retinopathy due to its metabolic influence and neuroprotective effects; for macular degeneration due to the antioxidant and neuroprotective properties; and for uveitis, mostly owing to anti-inflammatory and immunomodulatory properties. This paper reviews the scientific evidence supporting the use of melatonin in different ocular districts. Moreover, it provides data suggesting that the topical administration of melatonin as eye drops is a real possibility, utilizing nanotechnological formulations that could improve its solubility and permeation through the eye. This way, its distribution and concentration in different ocular tissues may support its pleiotropic therapeutic effects.
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Affiliation(s)
- Dario Rusciano
- Fidia Research Centre, c/o University of Catania, Via Santa Sofia 89, 95123 Catania, Italy
| | - Cristina Russo
- Department of Biomedical and Biotechnological Sciences, University of Catania, Via Santa Sofia 89, 95123 Catania, Italy;
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Hussain A, Gopalakrishnan A, Scott H, Seby C, Tang V, Ostrin L, Chakraborty R. Associations between systemic melatonin and human myopia: A systematic review. Ophthalmic Physiol Opt 2023; 43:1478-1490. [PMID: 37568264 DOI: 10.1111/opo.13214] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 07/31/2023] [Accepted: 08/01/2023] [Indexed: 08/13/2023]
Abstract
PURPOSE Experimental models have implicated the role of melatonin circadian rhythm disruption in refractive error development. Recent studies have examined melatonin concentration and its diurnal patterns on refractive error with equivocal results. This systematic review aimed to summarise the literature on melatonin circadian rhythms in myopia. RECENT FINDINGS PubMed, EMBASE, Web of Science, Scopus, ProQuest Central, LILACS, Cochrane and Medline databases were searched for papers between January 2010 and December 2022 using defined search terms. Seven studies measured melatonin and circadian rhythms in three biological fluids (blood serum, saliva and urine) in both myopes and non-myopes. Morning melatonin concentrations derived from blood serum varied significantly between studies in individuals aged 10-30 years, with a maximum of 89.45 pg/mL and a minimum of 5.43 pg/mL using liquid chromatography and mass spectrometry. The diurnal variation of salivary melatonin was not significantly different between myopes and emmetropes when measured every 4 h for 24 h and quantified with enzyme-linked immunosorbent assay. Significantly elevated salivary melatonin concentrations were reported in myopes compared with emmetropes, aged 18-30 years when measured hourly from evening until their habitual bedtime using liquid chromatography. However, the relationship between dim light melatonin onset and refractive group was inconsistent between studies. The 6-sulphatoxymelatonin concentration derived from overnight urine volume, measured using a double antibody radioimmunoassay, was found to be significantly lower in myopes (29.17 pg/mL) than emmetropes (42.51 pg/mL). SUMMARY The role of melatonin concentration and rhythm in myopia has not been studied extensively. This systematic review confirms conflicting findings across studies, with potential relationships existing. Future studies with uniform methodological approaches are required to ascertain the causal relationship between melatonin dysregulation and myopia in humans.
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Affiliation(s)
- Azfira Hussain
- Myopia Clinic, Unit of Medical Research Foundation, Sankara Nethralaya, Chennai, Tamil Nadu, India
| | - Aparna Gopalakrishnan
- Myopia Clinic, Unit of Medical Research Foundation, Sankara Nethralaya, Chennai, Tamil Nadu, India
| | - Hannah Scott
- Flinders Health and Medical Research Institute: Sleep Health, Flinders University, Adelaide, South Australia, Australia
| | - Chris Seby
- Caring Futures Institute, Myopia and Visual Development Lab, College of Nursing and Health Sciences, Flinders University, Adelaide, South Australia, Australia
| | - Victoria Tang
- Caring Futures Institute, Myopia and Visual Development Lab, College of Nursing and Health Sciences, Flinders University, Adelaide, South Australia, Australia
| | - Lisa Ostrin
- College of Optometry, University of Houston, Houston, Texas, USA
| | - Ranjay Chakraborty
- Caring Futures Institute, Myopia and Visual Development Lab, College of Nursing and Health Sciences, Flinders University, Adelaide, South Australia, Australia
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5
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Hu S, Jing Y, Li T, Wang YG, Liu Z, Gao J, Tian YC. Inferring circadian gene regulatory relationships from gene expression data with a hybrid framework. BMC Bioinformatics 2023; 24:362. [PMID: 37752445 PMCID: PMC10521455 DOI: 10.1186/s12859-023-05458-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Accepted: 08/30/2023] [Indexed: 09/28/2023] Open
Abstract
BACKGROUND The central biological clock governs numerous facets of mammalian physiology, including sleep, metabolism, and immune system regulation. Understanding gene regulatory relationships is crucial for unravelling the mechanisms that underlie various cellular biological processes. While it is possible to infer circadian gene regulatory relationships from time-series gene expression data, relying solely on correlation-based inference may not provide sufficient information about causation. Moreover, gene expression data often have high dimensions but a limited number of observations, posing challenges in their analysis. METHODS In this paper, we introduce a new hybrid framework, referred to as Circadian Gene Regulatory Framework (CGRF), to infer circadian gene regulatory relationships from gene expression data of rats. The framework addresses the challenges of high-dimensional data by combining the fuzzy C-means clustering algorithm with dynamic time warping distance. Through this approach, we efficiently identify the clusters of genes related to the target gene. To determine the significance of genes within a specific cluster, we employ the Wilcoxon signed-rank test. Subsequently, we use a dynamic vector autoregressive method to analyze the selected significant gene expression profiles and reveal directed causal regulatory relationships based on partial correlation. CONCLUSION The proposed CGRF framework offers a comprehensive and efficient solution for understanding circadian gene regulation. Circadian gene regulatory relationships are inferred from the gene expression data of rats based on the Aanat target gene. The results show that genes Pde10a, Atp7b, Prok2, Per1, Rhobtb3 and Dclk1 stand out, which have been known to be essential for the regulation of circadian activity. The potential relationships between genes Tspan15, Eprs, Eml5 and Fsbp with a circadian rhythm need further experimental research.
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Affiliation(s)
- Shuwen Hu
- School of Computer Science, Queensland University of Technology, Brisbane, QLD, 4001, Australia
- Agriculture and Food, CSIRO, St Lucia, QLD, 4067, Australia
| | - Yi Jing
- Faculty of Science, The University of New South Wales, Sydney, 2052, Australia
| | - Tao Li
- School of Life Sciences, Inner Mongolia Agricultural University, Hohhot, 010018, China
| | - You-Gan Wang
- Institute for Learning Sciences and Teacher Education, Australian Catholic University, Brisbane, QLD, 4000, Australia
| | - Zhenyu Liu
- School of Computer and Information Engineering, Inner Mongolia Agriculture University, Hohhot, 010018, China
| | - Jing Gao
- School of Computer and Information Engineering, Inner Mongolia Agriculture University, Hohhot, 010018, China.
| | - Yu-Chu Tian
- School of Computer Science, Queensland University of Technology, Brisbane, QLD, 4001, Australia.
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6
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Celiker C, Weissova K, Cerna KA, Oppelt J, Dorgau B, Gambin FM, Sebestikova J, Lako M, Sernagor E, Liskova P, Barta T. Light-responsive microRNA molecules in human retinal organoids are differentially regulated by distinct wavelengths of light. iScience 2023; 26:107237. [PMID: 37485345 PMCID: PMC10362355 DOI: 10.1016/j.isci.2023.107237] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Revised: 05/30/2023] [Accepted: 06/25/2023] [Indexed: 07/25/2023] Open
Abstract
Cells in the human retina must rapidly adapt to constantly changing visual stimuli. This fast adaptation to varying levels and wavelengths of light helps to regulate circadian rhythms and allows for adaptation to high levels of illumination, thereby enabling the rest of the visual system to remain responsive. It has been shown that retinal microRNA (miRNA) molecules play a key role in regulating these processes. However, despite extensive research using various model organisms, light-regulated miRNAs in human retinal cells remain unknown. Here, we aim to characterize these miRNAs. We generated light-responsive human retinal organoids that express miRNA families and clusters typically found in the retina. Using an in-house developed photostimulation device, we identified a subset of light-regulated miRNAs. Importantly, we found that these miRNAs are differentially regulated by distinct wavelengths of light and have a rapid turnover, highlighting the dynamic and adaptive nature of the human retina.
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Affiliation(s)
- Canan Celiker
- Department of Histology and Embryology, Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - Kamila Weissova
- Department of Histology and Embryology, Faculty of Medicine, Masaryk University, Brno, Czech Republic
- Institute of Animal Physiology and Genetics, The Czech Academy of Sciences, Brno, Czech Republic
| | - Katerina Amruz Cerna
- Department of Histology and Embryology, Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - Jan Oppelt
- Department of Pathology and Laboratory Medicine, Division of Neuropathology, Philadelphia, PA, USA
| | - Birthe Dorgau
- Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - Francisco Molina Gambin
- Department of Histology and Embryology, Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - Jana Sebestikova
- Department of Histology and Embryology, Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - Majlinda Lako
- Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - Evelyne Sernagor
- Biosciences Institute, Newcastle University, Newcastle upon Tyne NE1 7RU, UK
| | - Petra Liskova
- Department of Paediatrics and Inherited Metabolic Disorders, First Faculty of Medicine, Charles University, Prague, Czech Republic
| | - Tomas Barta
- Department of Histology and Embryology, Faculty of Medicine, Masaryk University, Brno, Czech Republic
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7
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Bhoi JD, Goel M, Ribelayga CP, Mangel SC. Circadian clock organization in the retina: From clock components to rod and cone pathways and visual function. Prog Retin Eye Res 2023; 94:101119. [PMID: 36503722 PMCID: PMC10164718 DOI: 10.1016/j.preteyeres.2022.101119] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 08/22/2022] [Accepted: 08/25/2022] [Indexed: 12/13/2022]
Abstract
Circadian (24-h) clocks are cell-autonomous biological oscillators that orchestrate many aspects of our physiology on a daily basis. Numerous circadian rhythms in mammalian and non-mammalian retinas have been observed and the presence of an endogenous circadian clock has been demonstrated. However, how the clock and associated rhythms assemble into pathways that support and control retina function remains largely unknown. Our goal here is to review the current status of our knowledge and evaluate recent advances. We describe many previously-observed retinal rhythms, including circadian rhythms of morphology, biochemistry, physiology, and gene expression. We evaluate evidence concerning the location and molecular machinery of the retinal circadian clock, as well as consider findings that suggest the presence of multiple clocks. Our primary focus though is to describe in depth circadian rhythms in the light responses of retinal neurons with an emphasis on clock control of rod and cone pathways. We examine evidence that specific biochemical mechanisms produce these daily light response changes. We also discuss evidence for the presence of multiple circadian retinal pathways involving rhythms in neurotransmitter activity, transmitter receptors, metabolism, and pH. We focus on distinct actions of two dopamine receptor systems in the outer retina, a dopamine D4 receptor system that mediates circadian control of rod/cone gap junction coupling and a dopamine D1 receptor system that mediates non-circadian, light/dark adaptive regulation of gap junction coupling between horizontal cells. Finally, we evaluate the role of circadian rhythmicity in retinal degeneration and suggest future directions for the field of retinal circadian biology.
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Affiliation(s)
- Jacob D Bhoi
- Ruiz Department of Ophthalmology and Visual Science, McGovern Medical School, UTHEALTH-The University of Texas Health Science Center at Houston, Houston, TX, USA; Neuroscience Honors Research Program, William Marsh Rice University, Houston, TX, USA
| | - Manvi Goel
- Department of Neuroscience, Wexner Medical Center, College of Medicine, The Ohio State University, Columbus, OH, USA
| | - Christophe P Ribelayga
- Ruiz Department of Ophthalmology and Visual Science, McGovern Medical School, UTHEALTH-The University of Texas Health Science Center at Houston, Houston, TX, USA; Neuroscience Honors Research Program, William Marsh Rice University, Houston, TX, USA.
| | - Stuart C Mangel
- Department of Neuroscience, Wexner Medical Center, College of Medicine, The Ohio State University, Columbus, OH, USA.
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8
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Zhang C, Zhu Z, Zhao J, Li Y, Zhang Z, Zheng Y. Ubiquitous light-emitting diodes: Potential threats to retinal circadian rhythms and refractive development. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 862:160809. [PMID: 36502986 DOI: 10.1016/j.scitotenv.2022.160809] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Revised: 11/08/2022] [Accepted: 12/05/2022] [Indexed: 06/17/2023]
Abstract
The use of light-emitting diodes (LEDs) has increased considerably in the 21st century with humans living in a modern photoperiod with brighter nights and dimmer days. Prolonged exposure to LEDs, especially at night, is considered a new source of pollution because it may affect the synthesis and secretion of retinal melatonin and dopamine, resulting in negative impacts on retinal circadian clocks and potentially disrupting retinal circadian rhythms. The control of ocular refraction is believed to be related to retinal circadian rhythms. Moreover, the global prevalence of myopia has increased at an alarming rate in recent decades. The widespread use of LEDs and the rapid increase in the prevalence of myopia overlap, which is unlikely to be a coincidence. The connection among LEDs, retinal circadian rhythms, and refractive development is both fascinating and confusing. In this review, we aim to develop a systematic framework that includes LEDs, retinal circadian rhythms and refractive development. This paper summarizes the possible mechanisms by which LEDs may disrupt retinal circadian rhythms. We propose that prolonged exposure to LEDs may induce myopia by disrupting retinal circadian rhythms. Finally, we suggest several possible countermeasures to prevent LED interference on retinal circadian rhythms, with the hope of reducing the onset and progression of myopia.
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Affiliation(s)
- Chenchen Zhang
- Department of Ophthalmology, The Second Hospital of Jilin University, Changchun 130000, China
| | - Zhe Zhu
- Department of Ophthalmology, Eye Hospital of Shandong First Medical University, Shandong Eye Institute, Jinan 250000, China
| | - Jing Zhao
- Department of Ophthalmology, The Second Hospital of Jilin University, Changchun 130000, China
| | - Yanxia Li
- Department of Ophthalmology, The Second Hospital of Jilin University, Changchun 130000, China
| | - Zhaoying Zhang
- Department of Ophthalmology, The Second Hospital of Jilin University, Changchun 130000, China
| | - Yajuan Zheng
- Department of Ophthalmology, The Second Hospital of Jilin University, Changchun 130000, China.
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9
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Huang L, Chen X, Lin J, Fan X, Chen T, Yu Y, Chen J, Hu J. Association between sleep duration and myopia among Chinese children during the COVID-19 pandemic: A cross-sectional study. Front Public Health 2023; 10:1015138. [PMID: 36699911 PMCID: PMC9868807 DOI: 10.3389/fpubh.2022.1015138] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Accepted: 12/19/2022] [Indexed: 01/12/2023] Open
Abstract
Background The studies on the association between sleep duration and myopia are limited, and the evidence is inconsistent. This study aimed to evaluate the association between sleep duration and myopia, cycloplegic spherical equivalent (SE) and axial length (AL) among Chinese children during the Corona Virus Disease 2019 (COVID-19) pandemic. Methods The study was a cross-sectional study on Chinese children aged 6-18 years. The comprehensive ophthalmic examinations for children included cycloplegic SE, AL, and standardized questionnaires. The questionnaire included sleep duration, parental myopia, outdoor time, and continuous near work duration without breaks. Myopia was defined as SE ≤-0.50 diopters (D). Results A total of 1,140 children were included in the analyses, with 84.7% of myopic children and 74.4% of children's daily sleep duration being more than 8 h/d. In univariate regression analysis, compared with sleep duration < 8 h/d, children with sleep duration of 8-9 and >9 h/d were less myopia (p < 0.01 for all), and had less myopic SE (p < 0.01 for all), and shorter AL (p < 0.01 for all). After adjusting for age, gender, parental myopia, outdoor time, and continuous near work duration without breaks, sleep duration was not associated with myopia, cycloplegic SE, and AL (p > 0.05 for all). Conclusions This study showed sleep duration was related to myopia, cycloplegic SE, and AL among Chinese children during the COVID-19 pandemic-related lifestyles, but no independent association.
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Affiliation(s)
- Luoming Huang
- Department of Ophthalmology and Optometry, The School of Medical Technology and Engineering, Fujian Medical University, Fuzhou, China,The Research Center for Juvenile Myopia Prevention and Control of Fujian Province, Fuzhou, China
| | - Xuelan Chen
- Department of Ophthalmology, The Second Affiliated Hospital of Fujian Medical University, Quanzhou, China,The Research Center for Juvenile Myopia Prevention and Control of Fujian Province, Fuzhou, China,Engineering Research Center of Assistive Technology for Visual Impairment, Fujian Province University, Quanzhou, China
| | - Jiajia Lin
- Eye Institute and Affiliated Xiamen Eye Center of Xiamen University, Xiamen, China
| | | | - Ting Chen
- Department of Ophthalmology, The Second Affiliated Hospital of Fujian Medical University, Quanzhou, China,The Research Center for Juvenile Myopia Prevention and Control of Fujian Province, Fuzhou, China,Engineering Research Center of Assistive Technology for Visual Impairment, Fujian Province University, Quanzhou, China
| | - Yang Yu
- Department of Ophthalmology, The Second Affiliated Hospital of Fujian Medical University, Quanzhou, China,The Research Center for Juvenile Myopia Prevention and Control of Fujian Province, Fuzhou, China,Engineering Research Center of Assistive Technology for Visual Impairment, Fujian Province University, Quanzhou, China
| | - Jiaxin Chen
- Department of Ophthalmology, The Second Affiliated Hospital of Fujian Medical University, Quanzhou, China,The Research Center for Juvenile Myopia Prevention and Control of Fujian Province, Fuzhou, China,Engineering Research Center of Assistive Technology for Visual Impairment, Fujian Province University, Quanzhou, China
| | - Jianmin Hu
- Department of Ophthalmology and Optometry, The School of Medical Technology and Engineering, Fujian Medical University, Fuzhou, China,Department of Ophthalmology, The Second Affiliated Hospital of Fujian Medical University, Quanzhou, China,The Research Center for Juvenile Myopia Prevention and Control of Fujian Province, Fuzhou, China,Engineering Research Center of Assistive Technology for Visual Impairment, Fujian Province University, Quanzhou, China,*Correspondence: Jianmin Hu ✉
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10
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Vanoni EM, Nandrot EF. The Retinal Pigment Epithelium: Cells That Know the Beat! ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2023; 1415:539-545. [PMID: 37440084 DOI: 10.1007/978-3-031-27681-1_79] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/14/2023]
Abstract
The retinal pigment epithelium (RPE) ensures different functions crucial for photoreceptor survival, and thus for vision, such as photoreceptor outer segments (POS) phagocytosis and retinal adhesion. Both follow a circadian rhythm with an activity peak occurring respectively 1.5-2 and 3.5 h after light onset. Interestingly, we showed that two rodent models, β5-/- and Prpf31+/- mice, display distinct alterations in both functions leading to different phenotypes. Indeed, the phagocytic peak totally disappears in β5 knockout mice but is attenuated and shifted in Prpf31+/- mice. Conversely, the retinal adhesion peak only attenuated in β5-/- mice is lost in Prpf31+/- mice. These distinct alterations have different consequences on retinal homeostasis proportional to the observed defects: β5-/- mice progressively lose vision and accumulate RPE lipofuscin deposits, while Prpf31+/- mice develop RPE metabolic dysfunctions and gradual structural modifications indicative of cellular stress. Hence, animal models are useful to understand the importance of the proper regulation of these functions.
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Affiliation(s)
- Elora M Vanoni
- Therapeutics Department, Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| | - Emeline F Nandrot
- Therapeutics Department, Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France.
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11
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Moran AL, Fehilly JD, Floss Jones D, Collery R, Kennedy BN. Regulation of the rhythmic diversity of daily photoreceptor outer segment phagocytosis in vivo. FASEB J 2022; 36:e22556. [PMID: 36165194 PMCID: PMC9828801 DOI: 10.1096/fj.202200990rr] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Revised: 08/30/2022] [Accepted: 09/06/2022] [Indexed: 01/12/2023]
Abstract
Outer segment phagocytosis (OSP) is a highly-regulated, biological process wherein photoreceptor outer segment (OS) tips are cyclically phagocytosed by the adjacent retinal pigment epithelium (RPE) cells. Often an overlooked retinal process, rhythmic OSP ensures the maintenance of healthy photoreceptors and vision. Daily, the photoreceptors renew OS at their base and the most distal, and likely oldest, OS tips, are phagocytosed by the RPE, preventing the accumulation of photo-oxidative compounds by breaking down phagocytosed OS tips and recycling useful components to the photoreceptors. Light changes often coincide with an escalation of OSP and within hours the phagosomes formed in each RPE cell are resolved. In the last two decades, individual molecular regulators were elucidated. Some of the molecular machinery used by RPE cells for OSP is highly similar to mechanisms used by other phagocytic cells for the clearance of apoptotic cells. Consequently, in the RPE, many molecular regulators of retinal phagocytosis have been elucidated. However, there is still a knowledge gap regarding the key regulators of physiological OSP in vivo between endogenous photoreceptors and the RPE. Understanding the regulation of OSP is of significant clinical interest as age-related macular degeneration (AMD) and inherited retinal diseases (IRD) are linked with altered OSP. Here, we review the in vivo timing of OSP peaks in selected species and focus on the reported in vivo environmental and molecular regulators of OSP.
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Affiliation(s)
- Ailis L. Moran
- UCD School of Biomolecular and Biomedical ScienceUniversity College DublinDublinIreland,UCD Conway InstituteUniversity College DublinDublinIreland
| | - John D. Fehilly
- UCD School of Biomolecular and Biomedical ScienceUniversity College DublinDublinIreland,UCD Conway InstituteUniversity College DublinDublinIreland
| | - Daniel Floss Jones
- UCD School of Biomolecular and Biomedical ScienceUniversity College DublinDublinIreland,UCD Conway InstituteUniversity College DublinDublinIreland
| | - Ross Collery
- Department of Cell Biology, Neurobiology and AnatomyMedical College of WisconsinMilwaukeeWisconsinUSA,Department of Ophthalmology and Visual SciencesMedical College of Wisconsin Eye InstituteMilwaukeeWisconsinUSA
| | - Breandán N. Kennedy
- UCD School of Biomolecular and Biomedical ScienceUniversity College DublinDublinIreland,UCD Conway InstituteUniversity College DublinDublinIreland
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12
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Yu S, Cui K, Wu P, Wu B, Lu X, Huang R, Tang X, Lin J, Yang B, Zhao J, He Q, Liang X, Xu Y. Melatonin prevents experimental central serous chorioretinopathy in rats. J Pineal Res 2022; 73:e12802. [PMID: 35436360 DOI: 10.1111/jpi.12802] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 04/08/2022] [Accepted: 04/12/2022] [Indexed: 11/28/2022]
Abstract
Central serous chorioretinopathy (CSC) is a vision-threatening disease with no validated treatment and unclear pathogenesis. It is characterized by dilation and leakage of choroidal vasculature, resulting in the accumulation of subretinal fluid, and serous detachment of the neurosensory retina. Numerous studies have demonstrated that melatonin had multiple protective effects against endothelial dysfunction, vascular inflammation, and blood-retinal barrier (BRB) breakdown. However, the effect of melatonin on CSC, and its exact pathogenesis, is not well understood thus far. In this study, an experimental model was established by intravitreal injection of aldosterone in rats, which mimicked the features of CSC. Our results found that melatonin administration in advance significantly inhibited aldosterone-induced choroidal thickening and vasodilation by reducing the expression of calcium-activated potassium channel KCa2.3, and attenuated tortuosity of choroid vessels. Moreover, melatonin protected the BRB integrity and prevented the decrease in tight junction protein (ZO-1, occludin, and claudin-1) levels in the rat model induced by aldosterone. Additionally, the data also showed that intraperitoneal injection of melatonin in advance inhibited aldosterone-induced macrophage/microglia infiltration, and remarkably diminished the levels of inflammatory cytokines (interleukin-6 [IL-6], IL-1β, and cyclooxygenase-2), chemokines (chemokine C-C motif ligand 3, and C-X-C motif ligand 1), and matrix metalloproteinases (MMP-2 and MMP-9). Luzindole, as the nonselective MT1 and MT2 antagonist, and 4-phenyl-2-propionamidotetraline, as the selective MT2 antagonist, neutralized the melatonin-induced inhibition of choroidal thickening and choroidal vasodilation, indicating that melatonin might exert the effects via binding to its receptors. Furthermore, the IL-17A/nuclear factor-κB signaling pathway was activated by intravitreal administration of aldosterone, while it was suppressed in melatonin-treated in advance rat eyes. This study indicates that melatonin could serve as a promising safe therapeutic strategy for CSC patients.
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Affiliation(s)
- Shanshan Yu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Kaixuan Cui
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Peiqi Wu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Benjuan Wu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Xi Lu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Rong Huang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Xiaoyu Tang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Jianqiang Lin
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Boyu Yang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Jinfeng Zhao
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Qingjing He
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Xiaoling Liang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Yue Xu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
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13
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Parravano M, Eandi CM, Figus M, Lupidi M, Menchini F, Nicolo' M, Parisi V, Toto L, Viola F, Vujosevic S, Querques G. Effects of circadian rhythm disruption on retinal physiopathology: Considerations from a consensus of experts. Eur J Ophthalmol 2022; 32:2489-2493. [PMID: 35656746 PMCID: PMC9373193 DOI: 10.1177/11206721221106149] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The circadian rhythms originate within the organism and synchronize with cyclic
fluctuations in the external environment. It has been demonstrated that part of the human
genome is under control of the circadian clock and that a synchronizer that helps to
maintain daily rhythms is Melatonin, a neuro-hormone primarily synthesized by the pineal
gland during the night. The chronic disruption of circadian rhythm has been linked to many
conditions such as obesity, metabolic syndrome, type 2 diabetes, cancer, and
neurodegenerative diseases. Studies in the mice showed that the disruption of the retinal
circadian rhythm increases the decline during the aging of photoreceptors, accelerating
age-related disruption of cone cell structure, function, and viability and that the
melatonin receptor deletion seems to influence the health of retinal cells, speeding up
their aging. In conclusion, preserving the circadian rhythms could be to add to the
prevention and treatment of age-related degenerative retinal diseases, and although
additional studies are needed, melatonin could be a valid support to favor this
“chronoprotection action”.
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Affiliation(s)
| | - C M Eandi
- Department of Surgical Sciences, University of Torino, Torino, Italy.,Fondation Asile des Aveugles, Jules Gonin Eye Hospital, University of Lausanne, Lausanne, Switzerland.,Macula Onlus Foundation, Genoa, Italy
| | - M Figus
- Department of Surgical, Medical and Molecular Pathology and Critical Care Medicine, 9310University of Pisa, Pisa, Italy
| | - M Lupidi
- Macula Onlus Foundation, Genoa, Italy.,Eye Clinic, Department of Experimental and Clinical Medicine, Marche Polytechnic University, Ancona, Italy
| | - F Menchini
- Department of Medicine-Ophthalmology, University of Udine, Udine, Italy
| | - M Nicolo'
- Macula Onlus Foundation, Genoa, Italy.,Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health (DiNOGMI), 9302University of Genoa, Genoa, Italy.,IRCCS Ospedale Policlinico San Martino, University Eye Clinic of Genoa, Genoa, Italy
| | - V Parisi
- 61870IRCCS-Fondazione Bietti, Rome, Italy
| | - L Toto
- Ophthalmic Clinic, Department of Medicine and Science of Ageing, University "G. 9301d'Annunzio" of Chieti-Pescara, Chieti, Italy
| | - F Viola
- Foundation IRCCS Cà Grande Ospedale Maggiore Policlinico, 9304University of Milan, Milan, Italy
| | - S Vujosevic
- Department of Biomedical, Surgical and Dental Sciences University of Milan, Milan, Italy.,Eye Clinic, IRCCS MultiMedica, Milan, Italy
| | - G Querques
- Department of Ophthalmology, IRCCS Ospedale San Raffaele, University Vita-Salute, Milan, Italy
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14
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Fishman ES, Han JS, La Torre A. Oscillatory Behaviors of microRNA Networks: Emerging Roles in Retinal Development. Front Cell Dev Biol 2022; 10:831750. [PMID: 35186936 PMCID: PMC8847441 DOI: 10.3389/fcell.2022.831750] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Accepted: 01/07/2022] [Indexed: 01/02/2023] Open
Abstract
A broad repertoire of transcription factors and other genes display oscillatory patterns of expression, typically ranging from 30 min to 24 h. These oscillations are associated with a variety of biological processes, including the circadian cycle, somite segmentation, cell cycle, and metabolism. These rhythmic behaviors are often prompted by transcriptional feedback loops in which transcriptional activities are inhibited by their corresponding gene target products. Oscillatory transcriptional patterns have been proposed as a mechanism to drive biological clocks, the molecular machinery that transforms temporal information into accurate spatial patterning during development. Notably, several microRNAs (miRNAs) -small non-coding RNA molecules-have been recently shown to both exhibit rhythmic expression patterns and regulate oscillatory activities. Here, we discuss some of these new findings in the context of the developing retina. We propose that miRNA oscillations are a powerful mechanism to coordinate signaling pathways and gene expression, and that addressing the dynamic interplay between miRNA expression and their target genes could be key for a more complete understanding of many developmental processes.
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15
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Chakraborty R, Landis EG, Mazade R, Yang V, Strickland R, Hattar S, Stone RA, Iuvone PM, Pardue MT. Melanopsin modulates refractive development and myopia. Exp Eye Res 2022; 214:108866. [PMID: 34838844 PMCID: PMC8792255 DOI: 10.1016/j.exer.2021.108866] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Revised: 11/19/2021] [Accepted: 11/23/2021] [Indexed: 01/03/2023]
Abstract
Myopia, or nearsightedness, is the most common form of refractive abnormality and is characterized by excessive ocular elongation in relation to ocular power. Retinal neurotransmitter signaling, including dopamine, is implicated in myopic ocular growth, but the visual pathways that initiate and sustain myopia remain unclear. Melanopsin-expressing retinal ganglion cells (mRGCs), which detect light, are important for visual function, and have connections with retinal dopamine cells. Here, we investigated how mRGCs influence normal and myopic refractive development using two mutant mouse models: Opn4-/- mice that lack functional melanopsin photopigments and intrinsic mRGC responses but still receive other photoreceptor-mediated input to these cells; and Opn4DTA/DTA mice that lack intrinsic and photoreceptor-mediated mRGC responses due to mRGC cell death. In mice with intact vision or form-deprivation, we measured refractive error, ocular properties including axial length and corneal curvature, and the levels of retinal dopamine and its primary metabolite, L-3,4-dihydroxyphenylalanine (DOPAC). Myopia was measured as a myopic shift, or the difference in refractive error between the form-deprived and contralateral eyes. We found that Opn4-/- mice had altered normal refractive development compared to Opn4+/+ wildtype mice, starting ∼4D more myopic but developing ∼2D greater hyperopia by 16 weeks of age. Consistent with hyperopia at older ages, 16 week-old Opn4-/- mice also had shorter eyes compared to Opn4+/+ mice (3.34 vs 3.42 mm). Opn4DTA/DTA mice, however, were more hyperopic than both Opn4+/+ and Opn4-/- mice across development ending with even shorter axial lengths. Despite these differences, both Opn4-/- and Opn4DTA/DTA mice had ∼2D greater myopic shifts in response to form-deprivation compared to Opn4+/+ mice. Furthermore, when vision was intact, dopamine and DOPAC levels were similar between Opn4-/- and Opn4+/+ mice, but higher in Opn4DTA/DTA mice, which differed with age. However, form-deprivation reduced retinal dopamine and DOAPC by ∼20% in Opn4-/- compared to Opn4+/+ mice but did not affect retinal dopamine and DOPAC in Opn4DTA/DTA mice. Lastly, systemically treating Opn4-/- mice with the dopamine precursor L-DOPA reduced their form-deprivation myopia by half compared to non-treated mice. Collectively our findings show that disruption of retinal melanopsin signaling alters the rate and magnitude of normal refractive development, yields greater susceptibility to form-deprivation myopia, and changes dopamine signaling. Our results suggest that mRGCs participate in the eye's response to myopigenic stimuli, acting partly through dopaminergic mechanisms, and provide a potential therapeutic target underling myopia progression. We conclude that proper mRGC function is necessary for correct refractive development and protection from myopia progression.
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Affiliation(s)
- Ranjay Chakraborty
- Department of Ophthalmology, Emory University School of Medicine, 1365B Clifton Rd NE, Atlanta, GA 30322, United States,Center for Visual and Neurocognitive Rehabilitation, Atlanta VA Health Care System, 1670 Clairmont Rd, Decatur, GA 30033, United States,College of Nursing and Health Sciences, Optometry and Vision Science, Flinders University, Bedford Park, SA 5001, Adelaide, Australia,Caring Futures Institute, Flinders University, Bedford Park, SA 5042, Adelaide, Australia
| | - Erica G. Landis
- Department of Ophthalmology, Emory University School of Medicine, 1365B Clifton Rd NE, Atlanta, GA 30322, United States,Center for Visual and Neurocognitive Rehabilitation, Atlanta VA Health Care System, 1670 Clairmont Rd, Decatur, GA 30033, United States,Neuroscience Program, Emory University School of Medicine, 1365 Clifton Rd NE, Atlanta, GA 30322, United States
| | - Reece Mazade
- Center for Visual and Neurocognitive Rehabilitation, Atlanta VA Health Care System, 1670 Clairmont Rd, Decatur, GA 30033, United States,Department of Biomedical Engineering, Georgia Institute of Technology, 313 Ferst Dr, Atlanta, GA 30332, United States
| | - Victoria Yang
- Center for Visual and Neurocognitive Rehabilitation, Atlanta VA Health Care System, 1670 Clairmont Rd, Decatur, GA 30033, United States,Department of Biomedical Engineering, Georgia Institute of Technology, 313 Ferst Dr, Atlanta, GA 30332, United States
| | - Ryan Strickland
- Center for Visual and Neurocognitive Rehabilitation, Atlanta VA Health Care System, 1670 Clairmont Rd, Decatur, GA 30033, United States,Neuroscience Program, Emory University School of Medicine, 1365 Clifton Rd NE, Atlanta, GA 30322, United States
| | - Samer Hattar
- Section on Light and Circadian Rhythms, NIMH, NIH, 9000 Rockville Pike, Bethesda, Maryland, USA 20892
| | - Richard A. Stone
- Department of Ophthalmology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, United States
| | - P. Michael Iuvone
- Department of Ophthalmology, Emory University School of Medicine, 1365B Clifton Rd NE, Atlanta, GA 30322, United States,Department of Pharmacology, Emory University School of Medicine, 1365B Clifton Rd NE, Atlanta, GA 30322, United States
| | - Machelle T. Pardue
- Center for Visual and Neurocognitive Rehabilitation, Atlanta VA Health Care System, 1670 Clairmont Rd, Decatur, GA 30033, United States,Neuroscience Program, Emory University School of Medicine, 1365 Clifton Rd NE, Atlanta, GA 30322, United States,Department of Biomedical Engineering, Georgia Institute of Technology, 313 Ferst Dr, Atlanta, GA 30332, United States
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16
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Recent Advances in Chronotherapy Targeting Respiratory Diseases. Pharmaceutics 2021; 13:pharmaceutics13122008. [PMID: 34959290 PMCID: PMC8704788 DOI: 10.3390/pharmaceutics13122008] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 11/19/2021] [Accepted: 11/23/2021] [Indexed: 11/17/2022] Open
Abstract
Respiratory diseases contribute to a significant percentage of mortality and morbidity worldwide. The circadian rhythm is a natural biological process where our bodily functions align with the 24 h oscillation (sleep-wake cycle) process and are controlled by the circadian clock protein/gene. Disruption of the circadian rhythm could alter normal lung function. Chronotherapy is a type of therapy provided at specific time intervals based on an individual's circadian rhythm. This would allow the drug to show optimum action, and thereby modulate its pharmacokinetics to lessen unwanted or unintended effects. In this review, we deliberated on the recent advances employed in chrono-targeted therapeutics for chronic respiratory diseases.
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17
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Yefimova MG, Béré E, Cantereau-Becq A, Meunier-Balandre AC, Merceron B, Burel A, Merienne K, Ravel C, Becq F, Bourmeyster N. Myelinosome Organelles in the Retina of R6/1 Huntington Disease (HD) Mice: Ubiquitous Distribution and Possible Role in Disease Spreading. Int J Mol Sci 2021; 22:ijms222312771. [PMID: 34884576 PMCID: PMC8657466 DOI: 10.3390/ijms222312771] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Revised: 11/08/2021] [Accepted: 11/22/2021] [Indexed: 12/12/2022] Open
Abstract
Visual deficit is one of the complications of Huntington disease (HD), a fatal neurological disorder caused by CAG trinucleotide expansions in the Huntingtin gene, leading to the production of mutant Huntingtin (mHTT) protein. Transgenic HD R6/1 mice expressing human HTT exon1 with 115 CAG repeats recapitulate major features of the human pathology and exhibit a degeneration of the retina. Our aim was to gain insight into the ultrastructure of the pathological HD R6/1 retina by electron microscopy (EM). We show that the HD R6/1 retina is enriched with unusual organelles myelinosomes, produced by retinal neurons and glia. Myelinosomes are present in all nuclear and plexiform layers, in the synaptic terminals of photoreceptors, in the processes of retinal neurons and glial cells, and in the subretinal space. In vitro study shows that myelinosomes secreted by human retinal glial Müller MIO-M1 cells transfected with EGFP-mHTT-exon1 carry EGFP-mHTT-exon1 protein, as revealed by immuno-EM and Western-blotting. Myelinosomes loaded with mHTT-exon1 are incorporated by naive neuronal/neuroblastoma SH-SY5Y cells. This results in the emergence of mHTT-exon1 in recipient cells. This process is blocked by membrane fusion inhibitor MDL 28170. Conclusion: Incorporation of myelinosomes carrying mHTT-exon1 in recipient cells may contribute to HD spreading in the retina. Exploring ocular fluids for myelinosome presence could bring an additional biomarker for HD diagnostics.
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Affiliation(s)
- Marina G. Yefimova
- Laboratoire Signalisation et Transports Ioniques Membranaires, Université de Poitiers/CNRS, 1 Rue Georges Bonnet, 86022 Poitiers, France; (A.C.-B.); (A.-C.M.-B.); (F.B.); (N.B.)
- Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, 44 Pr. Thorez, 194233 St. Petersburg, Russia
- Laboratoire de Biologie de la Reproduction-CECOS, Hopital SUD, 16 Bd de Bulgarie, CEDEX, 35000 Rennes, France;
- Correspondence:
| | - Emile Béré
- Plateforme IMAGE-UP, 1 Rue Georges Bonnet, 86022 Poitiers, France; (E.B.); (B.M.)
| | - Anne Cantereau-Becq
- Laboratoire Signalisation et Transports Ioniques Membranaires, Université de Poitiers/CNRS, 1 Rue Georges Bonnet, 86022 Poitiers, France; (A.C.-B.); (A.-C.M.-B.); (F.B.); (N.B.)
- Plateforme IMAGE-UP, 1 Rue Georges Bonnet, 86022 Poitiers, France; (E.B.); (B.M.)
| | - Annie-Claire Meunier-Balandre
- Laboratoire Signalisation et Transports Ioniques Membranaires, Université de Poitiers/CNRS, 1 Rue Georges Bonnet, 86022 Poitiers, France; (A.C.-B.); (A.-C.M.-B.); (F.B.); (N.B.)
| | - Bruno Merceron
- Plateforme IMAGE-UP, 1 Rue Georges Bonnet, 86022 Poitiers, France; (E.B.); (B.M.)
| | - Agnès Burel
- Plateforme Mric TEM, BIOSIT UMS 34 80, Université de Rennes 1, 2 Av. Pr. Léon Bernard, CEDEX, 35043 Rennes, France;
| | - Karine Merienne
- Laboratory of Cognitive and Adaptive Neurosciences (LNCA), University of Strasbourg, 67000 Strasbourg, France;
- CNRS UMR 7364, 67000 Strasbourg, France
| | - Célia Ravel
- Laboratoire de Biologie de la Reproduction-CECOS, Hopital SUD, 16 Bd de Bulgarie, CEDEX, 35000 Rennes, France;
| | - Frédéric Becq
- Laboratoire Signalisation et Transports Ioniques Membranaires, Université de Poitiers/CNRS, 1 Rue Georges Bonnet, 86022 Poitiers, France; (A.C.-B.); (A.-C.M.-B.); (F.B.); (N.B.)
| | - Nicolas Bourmeyster
- Laboratoire Signalisation et Transports Ioniques Membranaires, Université de Poitiers/CNRS, 1 Rue Georges Bonnet, 86022 Poitiers, France; (A.C.-B.); (A.-C.M.-B.); (F.B.); (N.B.)
- Service de Biochimie, CHU de Poitiers, 1, Rue de la Milétrie, 86021 Poitiers, France
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18
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Stafford-Bell N, McVeigh J, Lingham G, Straker L, Eastwood PR, Yazar S, Mackey DA, Lee SSY. Associations of 12-year sleep behaviour trajectories from childhood to adolescence with myopia and ocular biometry during young adulthood. Ophthalmic Physiol Opt 2021; 42:19-27. [PMID: 34676908 DOI: 10.1111/opo.12905] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 09/15/2021] [Accepted: 09/17/2021] [Indexed: 11/29/2022]
Abstract
PURPOSE Cross-sectional studies have variably reported that poor sleep quality may be associated with myopia in children. Longitudinal data, collected over the ages when myopia develops and progresses, could provide new insights into the sleep-myopia paradigm. This study tested the hypothesis that 12-year trajectories of sleep behaviour from childhood to adolescence is associated with myopia during young adulthood. METHODS At the 5-, 8-, 10-, 14- and 17-year follow-ups of the longitudinal Raine Study, which has been following a cohort since their birth in 1989-1992, participants' parents/guardians completed the Child Behaviour Checklist questionnaire (CBCL), which collected information on their child's sleep behaviour and quality. The CBCL includes six questions measuring sleep behaviour, which parents rated as 0 = not true, 1 = somewhat/sometimes true, or 2 = very/often true. Scores were summed at each follow-up to form a composite "sleep behaviour score". Latent Class Growth Analysis (LCGA) was used to classify participants according to their 12-year trajectory of sleep behaviour. At the 20-year follow-up, an eye examination was performed which included cycloplegic autorefraction and axial length measurement. RESULTS The LCGA identified three clusters of participants based on their trajectory of sleep behaviour: those with minimal' (43.6% of the total Raine Study sample), 'declining' (48.9%), or 'persistent' (7.5%) sleep problems. A total of 1194 participants had ophthalmic data and longitudinal sleep data available for analysis (47.2% female, 85.6% Caucasian). No significant differences were observed in regards to age, sex, ethnicity or ocular parameters between trajectory groups. Unadjusted and fully adjusted analyses demonstrated that sleep problem behaviour was not significantly associated with changes in refractive error, axial length or corneal radius. CONCLUSIONS Our findings do not support the hypothesis that there is an association between sleep behaviour and myopia. Future longitudinal studies should explore sleep trajectory data pre- and post-myopia diagnosis to confirm our results.
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Affiliation(s)
- Nicholas Stafford-Bell
- Centre for Ophthalmology and Visual Sciences (incorporating the Lions Eye Institute), University of Western Australia, Perth, Western Australia, Australia.,Fiona Stanley Hospital, Murdoch, Western Australia, Australia
| | - Joanne McVeigh
- Curtin School of Allied Health, Curtin University, Perth, Western Australia, Australia.,Movement Physiology Laboratory, School of Physiology, University of Witwatersrand, Johannesburg, South Africa
| | - Gareth Lingham
- Centre for Ophthalmology and Visual Sciences (incorporating the Lions Eye Institute), University of Western Australia, Perth, Western Australia, Australia
| | - Leon Straker
- Curtin School of Allied Health, Curtin University, Perth, Western Australia, Australia
| | - Peter R Eastwood
- College of Medicine and Public Health, Flinders Health and Medical Research Institute, Flinders University, Adelaide, South Australia, Australia
| | - Seyhan Yazar
- Garvan-Weizmann Centre for Cellular Genomics, Garvan Institute of Medical Research, Darlinghurst, New South Wales, Australia
| | - David A Mackey
- Centre for Ophthalmology and Visual Sciences (incorporating the Lions Eye Institute), University of Western Australia, Perth, Western Australia, Australia.,School of Medicine, Menzies Research Institute Tasmania, University of Tasmania, Hobart, Tasmania, Australia.,Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, University of Melbourne, Melbourne, Victoria, Australia
| | - Samantha Sze-Yee Lee
- Centre for Ophthalmology and Visual Sciences (incorporating the Lions Eye Institute), University of Western Australia, Perth, Western Australia, Australia
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19
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Yang C, Georgiou M, Atkinson R, Collin J, Al-Aama J, Nagaraja-Grellscheid S, Johnson C, Ali R, Armstrong L, Mozaffari-Jovin S, Lako M. Pre-mRNA Processing Factors and Retinitis Pigmentosa: RNA Splicing and Beyond. Front Cell Dev Biol 2021; 9:700276. [PMID: 34395430 PMCID: PMC8355544 DOI: 10.3389/fcell.2021.700276] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2021] [Accepted: 07/09/2021] [Indexed: 12/20/2022] Open
Abstract
Retinitis pigmentosa (RP) is the most common inherited retinal disease characterized by progressive degeneration of photoreceptors and/or retinal pigment epithelium that eventually results in blindness. Mutations in pre-mRNA processing factors (PRPF3, 4, 6, 8, 31, SNRNP200, and RP9) have been linked to 15–20% of autosomal dominant RP (adRP) cases. Current evidence indicates that PRPF mutations cause retinal specific global spliceosome dysregulation, leading to mis-splicing of numerous genes that are involved in a variety of retina-specific functions and/or general biological processes, including phototransduction, retinol metabolism, photoreceptor disk morphogenesis, retinal cell polarity, ciliogenesis, cytoskeleton and tight junction organization, waste disposal, inflammation, and apoptosis. Importantly, additional PRPF functions beyond RNA splicing have been documented recently, suggesting a more complex mechanism underlying PRPF-RPs driven disease pathogenesis. The current review focuses on the key RP-PRPF genes, depicting the current understanding of their roles in RNA splicing, impact of their mutations on retinal cell’s transcriptome and phenome, discussed in the context of model species including yeast, zebrafish, and mice. Importantly, information on PRPF functions beyond RNA splicing are discussed, aiming at a holistic investigation of PRPF-RP pathogenesis. Finally, work performed in human patient-specific lab models and developing gene and cell-based replacement therapies for the treatment of PRPF-RPs are thoroughly discussed to allow the reader to get a deeper understanding of the disease mechanisms, which we believe will facilitate the establishment of novel and better therapeutic strategies for PRPF-RP patients.
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Affiliation(s)
- Chunbo Yang
- Biosciences Institute, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Maria Georgiou
- Biosciences Institute, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Robert Atkinson
- Biosciences Institute, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Joseph Collin
- Biosciences Institute, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Jumana Al-Aama
- Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia
| | | | - Colin Johnson
- Leeds Institute of Molecular Medicine, University of Leeds, Leeds, United Kingdom
| | - Robin Ali
- King's College London, London, United Kingdom
| | - Lyle Armstrong
- Biosciences Institute, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Sina Mozaffari-Jovin
- Medical Genetics Research Center, Mashhad University of Medical Sciences, Mashhad, Iran.,Department of Medical Genetics, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.,Department of Cellular Biochemistry, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
| | - Majlinda Lako
- Biosciences Institute, Newcastle University, Newcastle upon Tyne, United Kingdom
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20
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Wang J, Yang Y, Wang Z, Xu K, Xiao X, Mu W. Comparison of effects in sustained and diel-cycling hypoxia on hypoxia tolerance, histology, physiology and expression of clock genes in high latitude fish Phoxinus lagowskii. Comp Biochem Physiol A Mol Integr Physiol 2021; 260:111020. [PMID: 34166835 DOI: 10.1016/j.cbpa.2021.111020] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Revised: 06/19/2021] [Accepted: 06/19/2021] [Indexed: 01/26/2023]
Abstract
Phoxinus lagowskii is a popular fish in Chinese cuisine. Though it is found mainly in China's high-latitude regions, where diel-cycling hypoxia (DCH) is known to have unique impacts on aquatic organisms, there is little known about its response to hypoxia. Currently, nothing is known about the changes in blood parameters, gill and liver morphology, glucose and lipid metabolism, or expression of genes involved in clock and glucose metabolism in response to sustained hypoxia (SH) and diel-cycling hypoxia (DCH). To elucidate the influence of sustained and diel-cycling hypoxia on fish hypoxia tolerance, resting oxygen consumption (MO2) analysis was performed after ten days of hypoxia. This analysis revealed that hypoxia tolerance profoundly improved after ten days of either sustained or diel-cycling hypoxia acclimation, with DCH groups showing greater improvements than SH groups. Additionally, an increase in RBCs was found in P. lagowskii, suggesting an increase in the O2-carrying capacity of the blood to tolerate hypoxia. Hemoglobin (Hb) concentrations in P. lagowskii were increased at four days of diel-cycling hypoxia, confirming that physiological and metabolic adaptation to hypoxia is based on the duration of O2 exposure. Increased Hb and hematocrit (Hct) were found in DCH-exposed fish, both of which have been directly linked to high-latitude hypoxia tolerance. In the gills, lamella surface area increased in SH-exposed fish more than DCH-exposed fish, and these increases were accompanied by a decrease in the volume of interlamellar cell mass (ILCM). Histology changes in the liver showed a higher frequency of cytoplasmic vacuolization in DCH-exposed fish. PK increases in SH-exposed fish suggest that fish can use more energy sources in persistent hypoxia. Meanwhile, DCH-exposed fish use TG as an energy source. In SH-exposed fish, self-regulation of Cry1a was observed, whereas Cry1b gene was up-regulated significantly. In DCH-exposed fish, three of eight clock genes studied had increased expression, including Per1a, Clocka, and Cry1b, suggesting that SH and DCH result in different hypoxic responses. This study presents a novel approach to the study of fish responses to hypoxia in high latitude and shows that sustained hypoxia and diel-cycling hypoxia induce large differences in fish physiology.
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Affiliation(s)
- Jing Wang
- Key Laboratory of Biodiversity of Aquatic Organisms, College of Life Science and Technology, Harbin Normal University, Harbin 150025, China
| | - Yuting Yang
- Key Laboratory of Biodiversity of Aquatic Organisms, College of Life Science and Technology, Harbin Normal University, Harbin 150025, China
| | - Zhen Wang
- Key Laboratory of Biodiversity of Aquatic Organisms, College of Life Science and Technology, Harbin Normal University, Harbin 150025, China
| | - Kexin Xu
- Key Laboratory of Biodiversity of Aquatic Organisms, College of Life Science and Technology, Harbin Normal University, Harbin 150025, China
| | - Xin Xiao
- Key Laboratory of Biodiversity of Aquatic Organisms, College of Life Science and Technology, Harbin Normal University, Harbin 150025, China
| | - Weijie Mu
- Key Laboratory of Biodiversity of Aquatic Organisms, College of Life Science and Technology, Harbin Normal University, Harbin 150025, China.
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21
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A genome-wide microRNA screen identifies the microRNA-183/96/182 cluster as a modulator of circadian rhythms. Proc Natl Acad Sci U S A 2021; 118:2020454118. [PMID: 33443164 DOI: 10.1073/pnas.2020454118] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
The regulatory mechanisms of circadian rhythms have been studied primarily at the level of the transcription-translation feedback loops of protein-coding genes. Regulatory modules involving noncoding RNAs are less thoroughly understood. In particular, emerging evidence has revealed the important role of microRNAs (miRNAs) in maintaining the robustness of the circadian system. To identify miRNAs that have the potential to modulate circadian rhythms, we conducted a genome-wide miRNA screen using U2OS luciferase reporter cells. Among 989 miRNAs in the library, 120 changed the period length in a dose-dependent manner. We further validated the circadian regulatory function of an miRNA cluster, miR-183/96/182, both in vitro and in vivo. We found that all three members of this miRNA cluster can modulate circadian rhythms. Particularly, miR-96 directly targeted a core circadian clock gene, PER2. The knockout of the miR-183/96/182 cluster in mice showed tissue-specific effects on circadian parameters and altered circadian rhythms at the behavioral level. This study identified a large number of miRNAs, including the miR-183/96/182 cluster, as circadian modulators. We provide a resource for further understanding the role of miRNAs in the circadian network and highlight the importance of miRNAs as a genome-wide layer of circadian clock regulation.
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22
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Chakraborty R, Micic G, Thorley L, Nissen TR, Lovato N, Collins MJ, Lack LC. Myopia, or near-sightedness, is associated with delayed melatonin circadian timing and lower melatonin output in young adult humans. Sleep 2021; 44:5919543. [PMID: 33030546 DOI: 10.1093/sleep/zsaa208] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Revised: 07/29/2020] [Indexed: 12/14/2022] Open
Abstract
STUDY OBJECTIVES Myopia, or near-sightedness, is the most common refractive vision disorder and predisposes the eye to many blinding conditions in adulthood. Recent research has suggested that myopia is associated with increased endogenous melatonin production. Here we investigated the differences in melatonin circadian timing and output in young adult myopes and non-myopes (or emmetropes) as a pathogenesis for myopia. METHODS A total of 18 myopic (refractive error [mean ± standard deviation] -4.89 ± 2.16 dioptres) and 14 emmetropic participants (-0.09 ± 0.13 dioptres), aged 22.06 ± 2.35 years were recruited. Circadian timing was assessed using salivary dim light melatonin onset (DLMO), collected half-hourly for 7 h, beginning 5 h before and finishing 2 h after individual average sleep onset in a sleep laboratory. Total melatonin production was assessed via aMT6s levels from urine voids collected from 06:00 pm and until wake-up time the following morning. Objective measures of sleep timing were acquired a week prior to the sleep laboratory visit using an actigraphy device. RESULTS Myopes (22:19 ± 1.8 h) exhibited a DLMO phase-delay of 1 hr 12 min compared with emmetropes (21:07 ± 1.4 h), p = 0.026, d = 0.73. Urinary aMT6s melatonin levels were significantly lower among myopes (29.17 ± 18.67) than emmetropes (42.51 ± 23.97, p = 0.04, d = 0.63). Myopes also had a significant delay in sleep onset, greater sleep onset latency, shorter sleep duration, and more evening-type diurnal preference than emmetropes (all p < 0.05). CONCLUSIONS These findings suggest a potential association between circadian rhythms and myopia in humans.
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Affiliation(s)
- Ranjay Chakraborty
- College of Nursing and Health Sciences, Optometry and Vision Science, Sturt North, Flinders University, Adelaide, SA, Australia.,Caring Futures Institute, Flinders University, Adelaide, SA, Australia
| | - Gorica Micic
- Adelaide Institute for Sleep Health: A Flinders Centre of Research Excellence, College of Medicine and Public Health, Flinders University, Adelaide, SA, Australia
| | - Lisa Thorley
- College of Education, Psychology and Social Work, Flinders University, Adelaide, SA, Australia
| | - Taylah R Nissen
- College of Education, Psychology and Social Work, Flinders University, Adelaide, SA, Australia
| | - Nicole Lovato
- Adelaide Institute for Sleep Health: A Flinders Centre of Research Excellence, College of Medicine and Public Health, Flinders University, Adelaide, SA, Australia
| | - Michael J Collins
- Contact Lens and Visual Optics Laboratory, School of Optometry and Vision Science, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Leon C Lack
- Adelaide Institute for Sleep Health: A Flinders Centre of Research Excellence, College of Medicine and Public Health, Flinders University, Adelaide, SA, Australia.,College of Education, Psychology and Social Work, Flinders University, Adelaide, SA, Australia
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23
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Markwell EL, Feigl B, Zele AJ. Intrinsically photosensitive melanopsin retinal ganglion cell contributions to the pupillary light reflex and circadian rhythm. Clin Exp Optom 2021; 93:137-49. [DOI: 10.1111/j.1444-0938.2010.00479.x] [Citation(s) in RCA: 92] [Impact Index Per Article: 30.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Affiliation(s)
- Emma L Markwell
- Visual Science and Medical Retina Laboratory, Institute of Health and Biomedical Innovation and School of Optometry, Queensland University of Technology, Brisbane, Queensland, Australia
E‐mail:
| | - Beatrix Feigl
- Visual Science and Medical Retina Laboratory, Institute of Health and Biomedical Innovation and School of Optometry, Queensland University of Technology, Brisbane, Queensland, Australia
E‐mail:
| | - Andrew J Zele
- Visual Science and Medical Retina Laboratory, Institute of Health and Biomedical Innovation and School of Optometry, Queensland University of Technology, Brisbane, Queensland, Australia
E‐mail:
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24
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Clarkson-Townsend DA, Bales KL, Marsit CJ, Pardue MT. Light Environment Influences Developmental Programming of the Metabolic and Visual Systems in Mice. Invest Ophthalmol Vis Sci 2021; 62:22. [PMID: 33861321 PMCID: PMC8083116 DOI: 10.1167/iovs.62.4.22] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Accepted: 03/27/2021] [Indexed: 02/06/2023] Open
Abstract
Purpose Light is a salient cue that can influence neurodevelopment and the immune system. Light exposure out of sync with the endogenous clock causes circadian disruption and chronic disease. Environmental light exposure may contribute to developmental programming of metabolic and neurological systems but has been largely overlooked in Developmental Origins of Health and Disease (DOHaD) research. Here, we investigated whether developmental light exposure altered programming of visual and metabolic systems. Methods Pregnant mice and pups were exposed to control light (12:12 light:dark) or weekly light cycle inversions (circadian disruption [CD]) until weaning, after which male and female offspring were housed in control light and longitudinally measured to evaluate differences in growth (weight), glucose tolerance, visual function (optomotor response), and retinal function (electroretinogram), with and without high fat diet (HFD) challenge. Retinal microglia and macrophages were quantified by positive Iba1 and CD11b immunofluorescence. Results CD exposure caused impaired visual function and increased retinal immune cell expression in adult offspring. When challenged with HFD, CD offspring also exhibited altered retinal function and sex-specific impairments in glucose tolerance. Conclusions Overall, these findings suggest that the light environment contributes to developmental programming of the metabolic and visual systems, potentially promoting a pro-inflammatory milieu in the retina and increasing the risk of visual disease later in life.
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Affiliation(s)
- Danielle A. Clarkson-Townsend
- Gangarosa Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, United States
- Center for Visual and Neurocognitive Rehabilitation, Atlanta VA Healthcare System, Decatur, Georgia, United States
| | - Katie L. Bales
- Center for Visual and Neurocognitive Rehabilitation, Atlanta VA Healthcare System, Decatur, Georgia, United States
- Department of Ophthalmology, Emory University, Atlanta, Georgia, United States
| | - Carmen J. Marsit
- Gangarosa Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, United States
| | - Machelle T. Pardue
- Center for Visual and Neurocognitive Rehabilitation, Atlanta VA Healthcare System, Decatur, Georgia, United States
- Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, Georgia, United States
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25
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Brain-to-brain communication: the possible role of brain electromagnetic fields (As a Potential Hypothesis). Heliyon 2021; 7:e06363. [PMID: 33732922 PMCID: PMC7937662 DOI: 10.1016/j.heliyon.2021.e06363] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 12/29/2020] [Accepted: 02/22/2021] [Indexed: 11/23/2022] Open
Abstract
Up now, the communication between brains of different humans or animals has been confirmed and confined by the sensory medium and motor facilities of body. Recently, direct brain-to-brain communication (DBBC) outside the conventional five senses has been verified between animals and humans. Nevertheless, no empirical studies or serious discussion have been performed to elucidate the mechanism behind this process. The validation of DBBC has been documented via recording similar pattern of action potentials occurring in the brain cortex of two animals. With regard to action potentials in brain neurons, the magnetic field resulting from the action potentials created in neurons is one of the tools where the brain of one animal can affect the brain of another. It has been shown that different animals, even humans, have the power to understand the magnetic field. Cryptochrome, which exists in the retina and in different regions of the brain, has been confirmed to be able to perceive magnetic fields and convert magnetic fields to action potentials. Recently, iron particles (Fe3O4) believed to be functioning as magnets have been found in various parts of the brain, and are postulated as magnetic field receptors. Newly developed supersensitive magnetic sensors made of iron magnets that can sense the brain's magnetic field have suggested the idea that these Fe3O4 particles or magnets may be capable of perceiving the brain's extremely weak magnetic field. The present study suggests that it is possible the extremely week magnetic field in one animal's brain to transmit vital and accurate information to another animal's brain.
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26
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Öztürk M, Ingenwerth M, Sager M, von Gall C, Ali AAH. Does a Red House Affect Rhythms in Mice with a Corrupted Circadian System? Int J Mol Sci 2021; 22:2288. [PMID: 33669004 PMCID: PMC7956239 DOI: 10.3390/ijms22052288] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Revised: 02/12/2021] [Accepted: 02/24/2021] [Indexed: 02/05/2023] Open
Abstract
The circadian rhythms of body functions in mammals are controlled by the circadian system. The suprachiasmatic nucleus (SCN) in the hypothalamus orchestrates subordinate oscillators. Time information is conveyed from the retina to the SCN to coordinate an organism's physiology and behavior with the light/dark cycle. At the cellular level, molecular clockwork composed of interlocked transcriptional/translational feedback loops of clock genes drives rhythmic gene expression. Mice with targeted deletion of the essential clock gene Bmal1 (Bmal1-/-) have an impaired light input pathway into the circadian system and show a loss of circadian rhythms. The red house (RH) is an animal welfare measure widely used for rodents as a hiding place. Red plastic provides light at a low irradiance and long wavelength-conditions which affect the circadian system. It is not known yet whether the RH affects rhythmic behavior in mice with a corrupted circadian system. Here, we analyzed whether the RH affects spontaneous locomotor activity in Bmal1-/- mice under standard laboratory light conditions. In addition, mPER1- and p-ERK-immunoreactions, as markers for rhythmic SCN neuronal activity, and day/night plasma corticosterone levels were evaluated. Our findings indicate that application of the RH to Bmal1-/- abolishes rhythmic locomotor behavior and dampens rhythmic SCN neuronal activity. However, RH had no effect on the day/night difference in corticosterone levels.
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Affiliation(s)
- Menekse Öztürk
- Institute for Anatomy II, Medical Faculty, Heinrich-Heine-University, Moorenstrasse 5, 40225 Dusseldorf, Germany; (M.Ö.); (M.I.); (A.A.H.A.)
| | - Marc Ingenwerth
- Institute for Anatomy II, Medical Faculty, Heinrich-Heine-University, Moorenstrasse 5, 40225 Dusseldorf, Germany; (M.Ö.); (M.I.); (A.A.H.A.)
- Institute of Pathology, Medical Faculty, University Duisburg-Essen, Hufelandstrasse 55, 45147 Essen, Germany
| | - Martin Sager
- Central Institute for Animal Research and Animal Protection (ZETT), Medical Faculty, Heinrich Heine University, Moorenstrasse 5, 40225 Dusseldorf, Germany;
| | - Charlotte von Gall
- Institute for Anatomy II, Medical Faculty, Heinrich-Heine-University, Moorenstrasse 5, 40225 Dusseldorf, Germany; (M.Ö.); (M.I.); (A.A.H.A.)
| | - Amira A. H. Ali
- Institute for Anatomy II, Medical Faculty, Heinrich-Heine-University, Moorenstrasse 5, 40225 Dusseldorf, Germany; (M.Ö.); (M.I.); (A.A.H.A.)
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27
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Korshunov KS, Blakemore LJ, Trombley PQ. Illuminating and Sniffing Out the Neuromodulatory Roles of Dopamine in the Retina and Olfactory Bulb. Front Cell Neurosci 2020; 14:275. [PMID: 33110404 PMCID: PMC7488387 DOI: 10.3389/fncel.2020.00275] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Accepted: 08/04/2020] [Indexed: 01/28/2023] Open
Abstract
In the central nervous system, dopamine is well-known as the neuromodulator that is involved with regulating reward, addiction, motivation, and fine motor control. Yet, decades of findings are revealing another crucial function of dopamine: modulating sensory systems. Dopamine is endogenous to subsets of neurons in the retina and olfactory bulb (OB), where it sharpens sensory processing of visual and olfactory information. For example, dopamine modulation allows the neural circuity in the retina to transition from processing dim light to daylight and the neural circuity in the OB to regulate odor discrimination and detection. Dopamine accomplishes these tasks through numerous, complex mechanisms in both neural structures. In this review, we provide an overview of the established and emerging research on these mechanisms and describe similarities and differences in dopamine expression and modulation of synaptic transmission in the retinas and OBs of various vertebrate organisms. This includes discussion of dopamine neurons’ morphologies, potential identities, and biophysical properties along with their contributions to circadian rhythms and stimulus-driven synthesis, activation, and release of dopamine. As dysregulation of some of these mechanisms may occur in patients with Parkinson’s disease, these symptoms are also discussed. The exploration and comparison of these two separate dopamine populations shows just how remarkably similar the retina and OB are, even though they are functionally distinct. It also shows that the modulatory properties of dopamine neurons are just as important to vision and olfaction as they are to motor coordination and neuropsychiatric/neurodegenerative conditions, thus, we hope this review encourages further research to elucidate these mechanisms.
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Affiliation(s)
- Kirill S Korshunov
- Department of Biological Science, Florida State University, Tallahassee, FL, United States.,Program in Neuroscience, Florida State University, Tallahassee, FL, United States
| | - Laura J Blakemore
- Department of Biological Science, Florida State University, Tallahassee, FL, United States.,Program in Neuroscience, Florida State University, Tallahassee, FL, United States
| | - Paul Q Trombley
- Department of Biological Science, Florida State University, Tallahassee, FL, United States.,Program in Neuroscience, Florida State University, Tallahassee, FL, United States
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28
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Walters D, Vogel KR, Brown M, Shi X, Roullet JB, Gibson KM. Transcriptome analysis in mice treated with vigabatrin identifies dysregulation of genes associated with retinal signaling circuitry. Epilepsy Res 2020; 166:106395. [PMID: 32679486 DOI: 10.1016/j.eplepsyres.2020.106395] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 06/02/2020] [Accepted: 06/09/2020] [Indexed: 10/24/2022]
Abstract
Vigabatrin (VGB; γ-vinyl-GABA) is an antiepileptic drug that elevates CNS GABA via irreversible inactivation of the GABA catabolic enzyme GABA-transaminase. VGB's clinical utility, however, can be curtailed by peripheral visual field constriction (pVFC) and thinning of the retinal nerve fiber layer (RNFL). Earlier studies from our laboratory revealed disruptions of autophagy by VGB. Here, we tested the hypothesis that VGB administration to animals would reveal alterations of gene expression in VGB-treated retina that associated with autophagy. VGB (140 mg/kg/d; subcutaneous minipump) was continuously administered to mice (n = 6 each VGB/vehicle) for 12 days, after which animals were euthanized. Retina was isolated for transcriptome (RNAseq) analysis and further validation using qRT-PCR and immunohistochemistry (IHC). For 112 differentially expressed retinal genes (RNAseq), two databases (Gene Ontology; Kyoto Encyclopedia of Genes and Genomes) were used to identify genes associated with visual function. Twenty four genes were subjected to qRT-PCR validation, and five (Gb5, Bdnf, Cplx9, Crh, Sox9) revealed significant dysregulation. IHC of fixed retinas verified significant down-regulation of Gb5 in photoreceptor cells. All of these genes have been previously shown to play a role in retinal function/circuitry signaling. Minimal impact of VGB on retinal autophagic gene expression was observed. This is the first transcriptome analysis of retinal gene expression associated with VGB intake, highlighting potential novel molecular targets potentially related to VGB's well known ocular toxicity.
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Affiliation(s)
- Dana Walters
- Department of Pharmacotherapy, Washington State University College of Pharmacy and Pharmaceutical Sciences, Spokane, WA, USA.
| | - Kara R Vogel
- Department of Ophthalmology and Visual Sciences, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA.
| | - Madalyn Brown
- Department of Pharmacotherapy, Washington State University College of Pharmacy and Pharmaceutical Sciences, Spokane, WA, USA.
| | - Xutong Shi
- Department of Pharmacotherapy, Washington State University College of Pharmacy and Pharmaceutical Sciences, Spokane, WA, USA.
| | - Jean-Baptiste Roullet
- Department of Pharmacotherapy, Washington State University College of Pharmacy and Pharmaceutical Sciences, Spokane, WA, USA.
| | - K Michael Gibson
- Department of Pharmacotherapy, Washington State University College of Pharmacy and Pharmaceutical Sciences, Spokane, WA, USA.
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29
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Clemenzi MN, Martchenko A, Loganathan N, Tse EK, Brubaker PL, Belsham DD. Analysis of Western diet, palmitate and BMAL1 regulation of neuropeptide Y expression in the murine hypothalamus and BMAL1 knockout cell models. Mol Cell Endocrinol 2020; 507:110773. [PMID: 32114021 DOI: 10.1016/j.mce.2020.110773] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Revised: 02/19/2020] [Accepted: 02/24/2020] [Indexed: 12/20/2022]
Abstract
Western diets that are high in saturated fat and sugar disrupt circadian rhythms, induce weight gain, and lead to metabolic diseases including obesity. However, the mechanistic link between altered circadian rhythms and energy homeostasis remains poorly understood. In C57BL/6J mice, consuming a Western diet for 16 weeks significantly reduced food intake (at zeitgeber 12-16), in association with decreases in hypothalamic expression of the orexigenic neuropeptides, neuropeptide Y (Npy) and agouti-related peptide (AgRP). To examine the acute effects of the most prevalent saturated fatty acid in a Western diet, palmitate, and the role of the core clock gene, Bmal1, in the regulation of hypothalamic feeding neuropeptides, we used heterogeneous and clonal BMAL1 knockout (KO) immortalized hypothalamic cell lines, expressing specific neuropeptides, derived from male (M) and female (F) mice. Both mHypoA-BMAL1-KO/F and mHypoA-BMAL1-KO/M cells demonstrated a loss of circadian rhythmicity in expression of the clock gene, Per2, as compared to wild-type (control) cultures. Loss of BMAL1 also altered the time-dependent expression of Npy and proopiomelanocortin, and disrupted AgRP rhythmicity. Furthermore, palmitate increased BMAL1 binding to the Npy promotor region, and palmitate treatment (50 μM for 24 h) stimulated Npy expression in a BMAL1-dependent manner in both heterogeneous and clonal NPY-expressing female-derived cell models. The results of this study demonstrate that circadian expression of Bmal1 serves as a mechanistic link between Western diet- and palmitate-induced disruptions of the normal rhythmic patterns in hypothalamic feeding-related neuropeptides.
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Affiliation(s)
| | | | - Neruja Loganathan
- Department of Physiology, University of Toronto, Toronto, ON, Canada
| | - Erika K Tse
- Department of Physiology, University of Toronto, Toronto, ON, Canada
| | - Patricia L Brubaker
- Department of Physiology, University of Toronto, Toronto, ON, Canada; Department of Medicine, University of Toronto, Toronto, ON, Canada
| | - Denise D Belsham
- Department of Physiology, University of Toronto, Toronto, ON, Canada; Department of Medicine, University of Toronto, Toronto, ON, Canada; Department of Obstetrics and Gynaecology, University of Toronto, Toronto, ON, Canada.
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30
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Pinato L, Galina Spilla CS, Markus RP, da Silveira Cruz-Machado S. Dysregulation of Circadian Rhythms in Autism Spectrum Disorders. Curr Pharm Des 2020; 25:4379-4393. [DOI: 10.2174/1381612825666191102170450] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2019] [Accepted: 10/31/2019] [Indexed: 12/12/2022]
Abstract
Background:
The alterations in neurological and neuroendocrine functions observed in the autism
spectrum disorder (ASD) involves environmentally dependent dysregulation of neurodevelopment, in interaction
with multiple coding gene defects. Disturbed sleep-wake patterns, as well as abnormal melatonin and glucocorticoid
secretion, show the relevance of an underlying impairment of the circadian timing system to the behavioral
phenotype of ASD. Thus, understanding the mechanisms involved in the circadian dysregulation in ASD could
help to identify early biomarkers to improve the diagnosis and therapeutics as well as providing a significant
impact on the lifelong prognosis.
Objective:
In this review, we discuss the organization of the circadian timing system and explore the connection
between neuroanatomic, molecular, and neuroendocrine responses of ASD and its clinical manifestations. Here
we propose interconnections between circadian dysregulation, inflammatory baseline and behavioral changes in
ASD. Taking into account, the high relevancy of melatonin in orchestrating both circadian timing and the maintenance
of physiological immune quiescence, we raise the hypothesis that melatonin or analogs should be considered
as a pharmacological approach to suppress inflammation and circadian misalignment in ASD patients.
Strategy:
This review provides a comprehensive update on the state-of-art of studies related to inflammatory
states and ASD with a special focus on the relationship with melatonin and clock genes. The hypothesis raised
above was analyzed according to the published data.
Conclusion:
Current evidence supports the existence of associations between ASD to circadian dysregulation,
behavior problems, increased inflammatory levels of cytokines, sleep disorders, as well as reduced circadian
neuroendocrine responses. Indeed, major effects may be related to a low melatonin rhythm. We propose that
maintaining the proper rhythm of the circadian timing system may be helpful to improve the health and to cope
with several behavioral changes observed in ASD subjects.
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Affiliation(s)
- Luciana Pinato
- Department of Speech, Language and Hearing Sciences, São Paulo State University (UNESP), 17525-900, Marilia, SP, Brazil
| | - Caio Sergio Galina Spilla
- Department of Speech, Language and Hearing Sciences, São Paulo State University (UNESP), 17525-900, Marilia, SP, Brazil
| | - Regina Pekelmann Markus
- Laboratory of Chronopharmacology, Department of Physiology, Institute of Biosciences, University of São Paulo (USP), 05508-090, São Paulo, SP, Brazil
| | - Sanseray da Silveira Cruz-Machado
- Laboratory of Chronopharmacology, Department of Physiology, Institute of Biosciences, University of São Paulo (USP), 05508-090, São Paulo, SP, Brazil
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31
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Ko GYP. Circadian regulation in the retina: From molecules to network. Eur J Neurosci 2020; 51:194-216. [PMID: 30270466 PMCID: PMC6441387 DOI: 10.1111/ejn.14185] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Revised: 08/16/2018] [Accepted: 08/20/2018] [Indexed: 12/14/2022]
Abstract
The mammalian retina is the most unique tissue among those that display robust circadian/diurnal oscillations. The retina is not only a light sensing tissue that relays light information to the brain, it has its own circadian "system" independent from any influence from other circadian oscillators. While all retinal cells and retinal pigment epithelium (RPE) possess circadian oscillators, these oscillators integrate by means of neural synapses, electrical coupling (gap junctions), and released neurochemicals (such as dopamine, melatonin, adenosine, and ATP), so the whole retina functions as an integrated circadian system. Dysregulation of retinal clocks not only causes retinal or ocular diseases, it also impacts the circadian rhythm of the whole body, as the light information transmitted from the retina entrains the brain clock that governs the body circadian rhythms. In this review, how circadian oscillations in various retinal cells are integrated, and how retinal diseases affect daily rhythms.
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Affiliation(s)
- Gladys Y-P Ko
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas
- Texas A&M Institute for Neuroscience, Texas A&M University, College Station, Texas
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Ingram NT, Sampath AP, Fain GL. Voltage-clamp recordings of light responses from wild-type and mutant mouse cone photoreceptors. J Gen Physiol 2019; 151:1287-1299. [PMID: 31562185 PMCID: PMC6829558 DOI: 10.1085/jgp.201912419] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Revised: 08/15/2019] [Accepted: 08/30/2019] [Indexed: 01/16/2023] Open
Abstract
We describe the first extensive study of voltage-clamp current responses of cone photoreceptors in unlabeled, dark-adapted mouse retina using only the position and appearance of cone somata as a guide. Identification was confirmed from morphology after dye filling. Photocurrents recorded from wild-type mouse cones were biphasic with a fast cone component and a slower rod component. The rod component could be eliminated with dim background light and was not present in mouse lines lacking the rod transducin-α subunit (Gnat1-/- ) or connexin 36 (Cx36-/- ). Cones from Gnat1-/- or Cx36-/- mice had resting membrane potentials between -45 and -55 mV, peak photocurrents of 20-25 picoamps (pA) at a membrane potential Vm = -50 mV, sensitivities 60-70 times smaller than rods, and a total membrane capacitance two to four times greater than rods. The rate of activation (amplification constant) was largely independent of the brightness of the flash and was 1-2 s-2, less than half that of rods. The role of Ca2+-dependent transduction modulation was investigated by recording from cones in mice lacking rod transducin (Gnat1), recoverin, and/or the guanylyl-cyclase-activating proteins (GCAPs). In confirmation of previous results, responses of Gnat1-/- ;Gcaps-/- cones and triple-mutant Gnat1-/- ;Gcaps-/- ;Rv-/- cones recovered more slowly both to light flashes and steps and were more sensitive than cones expressing the GCAPs. Cones from all four mouse lines showed significant recovery and escaped saturation even in bright background light. This recovery occurred too rapidly to be caused by pigment bleaching or metaII decay and appears to reflect some modulation of response inactivation in addition to those produced by recoverin and the GCAPs. Our experiments now make possible a more detailed understanding of the cellular physiology of mammalian cone photoreceptors and the role of conductances in the inner and outer segment in producing cone light responses.
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Affiliation(s)
- Norianne T Ingram
- Department of Integrative Biology and Physiology, University of California, Los Angeles, Los Angeles, CA
- Department of Ophthalmology and Jules Stein Eye Institute, University of California, Los Angeles, Los Angeles, CA
| | - Alapakkam P Sampath
- Department of Ophthalmology and Jules Stein Eye Institute, University of California, Los Angeles, Los Angeles, CA
| | - Gordon L Fain
- Department of Integrative Biology and Physiology, University of California, Los Angeles, Los Angeles, CA
- Department of Ophthalmology and Jules Stein Eye Institute, University of California, Los Angeles, Los Angeles, CA
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Saha S, Singh KM, Gupta BBP. Melatonin synthesis and clock gene regulation in the pineal organ of teleost fish compared to mammals: Similarities and differences. Gen Comp Endocrinol 2019; 279:27-34. [PMID: 30026020 DOI: 10.1016/j.ygcen.2018.07.010] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2018] [Revised: 07/12/2018] [Accepted: 07/15/2018] [Indexed: 02/07/2023]
Abstract
The pineal organ of all vertebrates synthesizes and secretes melatonin in a rhythmic manner due to the circadian rhythm in the activity of arylalkylamine N-acetyltransferase (AANAT) - the rate-limiting enzyme in melatonin synthesis pathway. Nighttime increase in AANAT activity and melatonin synthesis depends on increased expression of aanat gene (a clock-controlled gene) and/or post-translation modification of AANAT protein. In mammalian and avian species, only one aanat gene is expressed. However, three aanat genes (aanat1a, aanat1b, and aanat2) are reported in fish species. While aanat1a and aanat1b genes are expressed in the fish retina, the nervous system and other peripheral tissues, aanat2 gene is expressed exclusively in the fish pineal organ. Clock genes form molecular components of the clockwork, which regulates clock-controlled genes like aanat gene. All core clock genes (i.e., clock, bmal1, per1, per2, per3, cry1 and cry2) and aanat2 gene (a clock-controlled gene) are expressed in the pineal organ of several fish species. There is a large body of information on regulation of clock genes, aanat gene and melatonin synthesis in the mammalian pineal gland. However, the information available on clock genes, aanat genes and melatonin synthesis in photoreceptive pineal organ of teleosts is fragmentary and not well documented. Therefore, we have reviewed published information on rhythmic expression of clock genes, aanat genes as well as synthesis of melatonin, and their regulation by photoperiod and temperature in teleostean pineal organ as compared to mammalian pineal gland. A critical analysis of the literature suggests that in contrast to the mammalian pineal gland, the pineal organ of teleosts (except salmonids) possesses a well developed indigenous clock composed of clock genes for regulation of rhythmic expression of aanat2 gene and melatonin synthesis. Further, the fish pineal organ also possesses essential molecular components for responding to light and temperature directly. The fish pineal organ seems to act as a potential master biological clock in most of the teleosts.
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Affiliation(s)
- Saurav Saha
- Environmental Endocrinology Laboratory, Department of Zoology, North-Eastern Hill University, Shillong 793022, India
| | - Kshetrimayum Manisana Singh
- Environmental Endocrinology Laboratory, Department of Zoology, North-Eastern Hill University, Shillong 793022, India
| | - Braj Bansh Prasad Gupta
- Environmental Endocrinology Laboratory, Department of Zoology, North-Eastern Hill University, Shillong 793022, India.
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Dopamine Signaling in Circadian Photoentrainment: Consequences of Desynchrony. THE YALE JOURNAL OF BIOLOGY AND MEDICINE 2019; 92:271-281. [PMID: 31249488 PMCID: PMC6585530] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Circadian rhythms, or biological oscillations of approximately 24 hours, impact almost all aspects of our lives by regulating the sleep-wake cycle, hormone release, body temperature fluctuation, and timing of food consumption. The molecular machinery governing these rhythms is similar across organisms ranging from unicellular fungi to insects, rodents, and humans. Circadian entrainment, or temporal synchrony with one's environment, is essential for survival. In mammals, the central circadian pacemaker is located in the suprachiasmatic nucleus (SCN) of the hypothalamus and mediates entrainment to environmental conditions. While the light:dark cycle is the primary environmental cue, arousal-inducing, non-photic signals such as food consumption, exercise, and social interaction are also potent synchronizers. Many of these stimuli enhance dopaminergic signaling suggesting that a cohesive circadian physiology depends on the relationship between circadian clocks and the neuronal circuits responsible for detecting salient events. Here, we review the inner workings of mammalian circadian entrainment, and describe the health consequences of circadian rhythm disruptions with an emphasis on dopamine signaling.
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Eshraghian JK, Baek S, Kim JH, Iannella N, Cho K, Goo YS, Iu HHC, Kang SM, Eshraghian K. Formulation and Implementation of Nonlinear Integral Equations to Model Neural Dynamics Within the Vertebrate Retina. Int J Neural Syst 2018; 28:1850004. [PMID: 29631506 DOI: 10.1142/s0129065718500041] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Existing computational models of the retina often compromise between the biophysical accuracy and a hardware-adaptable methodology of implementation. When compared to the current modes of vision restoration, algorithmic models often contain a greater correlation between stimuli and the affected neural network, but lack physical hardware practicality. Thus, if the present processing methods are adapted to complement very-large-scale circuit design techniques, it is anticipated that it will engender a more feasible approach to the physical construction of the artificial retina. The computational model presented in this research serves to provide a fast and accurate predictive model of the retina, a deeper understanding of neural responses to visual stimulation, and an architecture that can realistically be transformed into a hardware device. Traditionally, implicit (or semi-implicit) ordinary differential equations (OES) have been used for optimal speed and accuracy. We present a novel approach that requires the effective integration of different dynamical time scales within a unified framework of neural responses, where the rod, cone, amacrine, bipolar, and ganglion cells correspond to the implemented pathways. Furthermore, we show that adopting numerical integration can both accelerate retinal pathway simulations by more than 50% when compared with traditional ODE solvers in some cases, and prove to be a more realizable solution for the hardware implementation of predictive retinal models.
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Affiliation(s)
- Jason K Eshraghian
- 1 School of Electrical, Electronic and Computer Engineering, University of Western Australia, Crawley, Australia
| | - Seungbum Baek
- 2 College of Electrical and Computer Engineering, Chungbuk National University, Cheongju, Republic of Korea
| | - Jun-Ho Kim
- 2 College of Electrical and Computer Engineering, Chungbuk National University, Cheongju, Republic of Korea
| | | | - Kyoungrok Cho
- 2 College of Electrical and Computer Engineering, Chungbuk National University, Cheongju, Republic of Korea
| | - Yong Sook Goo
- 4 Department of Physiology, School of Medicine, Chungbuk National University, Cheongju, Republic of Korea
| | - Herbert H C Iu
- 1 School of Electrical, Electronic and Computer Engineering, University of Western Australia, Crawley, Australia
| | - Sung-Mo Kang
- 5 Department of Electrical Engineering, University of California, Santa Cruz, Santa Cruz, USA
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Huang DF, Wang MY, Yin W, Ma YQ, Wang H, Xue T, Ren DL, Hu B. Zebrafish Lacking Circadian Gene per2 Exhibit Visual Function Deficiency. Front Behav Neurosci 2018; 12:53. [PMID: 29593513 PMCID: PMC5859089 DOI: 10.3389/fnbeh.2018.00053] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Accepted: 03/01/2018] [Indexed: 01/09/2023] Open
Abstract
The retina has an intrinsic circadian clock, but the importance of this clock for vision is unknown. Zebrafish offer many advantages for studying vertebrate vision and circadian rhythm. Here, we explored the role of zebrafish per2, a light-regulated gene, in visual behavior and the underlying mechanisms. We observed that per2 mutant zebrafish larvae showed decreased contrast sensitivity and visual acuity using optokinetic response (OKR) assays. Using a visual motor response (VMR) assay, we observed normal OFF responses but abnormal ON responses in mutant zebrafish larvae. Immunofluorescence showed that mutants had a normal morphology of cone photoreceptor cells and retinal organization. However, electron microscopy showed that per2 mutants displayed abnormal and decreased photoreceptor ribbon synapses with arciform density, which resulted in retinal ON pathway defect. We also examined the expression of three cone opsins by quantitative real-time PCR (qRT-PCR), and the expression of long-wave-sensitive opsin (opn1lw) and short-wave-sensitive opsin (opn1sw) was reduced in mutant zebrafish larvae. qRT-PCR analyses also showed a down-regulation of the clock genes cry1ba and bmal1b in the adult eye of per2 mutant zebrafish. This study identified a mechanism by which a clock gene affects visual function and defined important roles of per2 in retinal information processing.
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Affiliation(s)
- Deng-Feng Huang
- Hefei National Laboratory for Physical Sciences at the Microscale and CAS Key Laboratory of Brain Function & Disease, School of Life Sciences, University of Science and Technology of China, Hefei, China
| | - Ming-Yong Wang
- School of Biology & Basic Medical Sciences, Medical College, Soochow University, Suzhou, China
| | - Wu Yin
- Hefei National Laboratory for Physical Sciences at the Microscale and CAS Key Laboratory of Brain Function & Disease, School of Life Sciences, University of Science and Technology of China, Hefei, China
| | - Yu-Qian Ma
- Neurodegenerative Disorder Research Center, University of Science and Technology of China, Hefei, China
| | - Han Wang
- School of Biology & Basic Medical Sciences, Medical College, Soochow University, Suzhou, China
| | - Tian Xue
- Neurodegenerative Disorder Research Center, University of Science and Technology of China, Hefei, China
| | - Da-Long Ren
- Hefei National Laboratory for Physical Sciences at the Microscale and CAS Key Laboratory of Brain Function & Disease, School of Life Sciences, University of Science and Technology of China, Hefei, China
| | - Bing Hu
- Hefei National Laboratory for Physical Sciences at the Microscale and CAS Key Laboratory of Brain Function & Disease, School of Life Sciences, University of Science and Technology of China, Hefei, China
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Baba K, Ribelayga CP, Michael Iuvone P, Tosini G. The Retinal Circadian Clock and Photoreceptor Viability. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1074:345-350. [PMID: 29721962 PMCID: PMC6003627 DOI: 10.1007/978-3-319-75402-4_42] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Circadian rhythms are present in most living organisms, and these rhythms are not just a consequence of the day/night fluctuation, but rather they are generated by endogenous biological clocks with a periodicity of about 24 h. In mammals, the master pacemaker of circadian rhythms is localized in the suprachiasmatic nuclei (SCN) of the hypothalamus. The SCN controls circadian rhythms in peripheral organs. The retina also contains circadian clocks which regulate many aspects of retinal physiology, independently of the SCN. Emerging experimental evidence indicates that the retinal circadian clocks also affect ocular health, and a few studies have now demonstrated that disruption of retinal clocks may contribute to the development of retinal diseases. Our study indicates that in mice lacking the clock gene Bmal1, photoreceptor viability during aging is significantly reduced. Bmal1 knockout mice at 8-9 months of age have 20-30% less nuclei in the outer nuclear layer. No differences were observed in the other retinal layers. Our study suggests that the retinal circadian clock is an important modulator of photoreceptor health.
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Affiliation(s)
- Kenkichi Baba
- Department of Pharmacology and Toxicology Morehouse School of Medicine, Neuroscience Institute, Atlanta, GA, USA.
| | - Christophe P Ribelayga
- Ruiz Department of Ophthalmology and Visual Science, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX, USA
| | - P Michael Iuvone
- Departments of Ophthalmology and Pharmacology, Emory University School of Medicine, Atlanta, GA, USA
| | - Gianluca Tosini
- Department of Pharmacology and Toxicology Morehouse School of Medicine, Neuroscience Institute, Atlanta, GA, USA
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Mishra I, Singh D, Kumar V. Temporal Expression of c-fos and Genes Coding for Neuropeptides and Enzymes of Amino Acid and Amine Neurotransmitter Biosynthesis in Retina, Pineal and Hypothalamus of a Migratory Songbird: Evidence for Circadian Rhythm-Dependent Seasonal Responses. Neuroscience 2017; 371:309-324. [PMID: 29273324 DOI: 10.1016/j.neuroscience.2017.12.016] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2017] [Revised: 12/10/2017] [Accepted: 12/12/2017] [Indexed: 10/18/2022]
Abstract
This study investigated whether, in photoperiodic songbirds, the circadian pacemaker system (CPS) connects to the seasonal photoperiodic responses, by changes at transcriptional level in the level and 24-h rhythm of its constituent neurotransmitters. We used black-headed buntings (Emberiza melanocephala), which exhibit distinct seasonal states in captivity under appropriate photoperiods and hence served as a useful model system. Under short days, buntings remain in the photosensitive state (Pse) (winter phenotype: non-migratory, non-breeding). Under long days, however, buntings undergo through early-photostimulated (spring phenotype: pre-migratory, pre-breeding), late photostimulated (summer phenotype: migratory, breeding) and photorefractory (autumn phenotype: post-breeding) states. During all four seasonal states, we measured in the retina, pineal and hypothalamus, which together form avian CPS, 4-hourly mRNA expression of c-fos (a neuronal-activity marker) and of genes coding for neuropeptides (vasoactive intestinal peptide, vip; somatostatin, sst; neuropeptide Y, npy) and for intermediary enzymes of amino acid (glutamate: glutaminase, gls and glutamic-oxaloacetic transaminase 2, got2; GABA: glutamic acid decarboxylase, gad65) and amine (dopamine: tyrosine hydroxylase, th) neurotransmitters biosynthetic pathway. There was a significant alteration in level and 24-h pattern of mRNA expression, albeit with seasonal differences in presence, waveform parameters and phase relationship of 24-h rhythm, of different genes. Particularly, mRNA expression of all candidate genes (except hypothalamic vip, pineal gls and retinal th) was arrhythmic in late photostimulated state. These results underscore that circadian rhythm of peptide, amino acid and amine neurotransmitter biosynthesis in CPS plays a critical role in the photoperiodic regulation of seasonal states in birds.
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Affiliation(s)
- Ila Mishra
- IndoUS Center for Biological Timing, Department of Zoology, University of Delhi, Delhi 110 007, India
| | - Devraj Singh
- IndoUS Center for Biological Timing, Department of Zoology, University of Delhi, Delhi 110 007, India
| | - Vinod Kumar
- IndoUS Center for Biological Timing, Department of Zoology, University of Delhi, Delhi 110 007, India.
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Marangoz D, Guzel E, Eyuboglu S, Gumusel A, Seckin I, Ciftci F, Yilmaz B, Yalvac I. Comparison of the neuroprotective effects of brimonidine tartrate and melatonin on retinal ganglion cells. Int Ophthalmol 2017; 38:2553-2562. [PMID: 29159432 DOI: 10.1007/s10792-017-0768-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2017] [Accepted: 11/12/2017] [Indexed: 02/07/2023]
Abstract
PURPOSE We aimed to compare the neuroprotective effects of brimonidine tartrate (BRT) and melatonin (MEL) on retinal ganglion cells (RGCs) in a rat glaucoma model. METHODS Thirty-six adult Wistar albino rats were allocated into six groups: control (C), glaucoma (G), BRT, MEL, G + BRT and G + MEL. After establishing the glaucoma model, intraocular pressure (IOP) of all animals measured at day 4 and day 30 was compared statistically with day 0 and day 4, respectively. Prior to sacrification at day 30 for histological evaluation and TUNEL analysis, retrograde labeling of non-apoptotic RGCs with 3% Fluorogold was performed and RGCs were evaluated under fluorescein microscope. RESULTS IOP measurements at day 4 were significantly higher than basal measurements in all glaucoma groups. BRT alone induced a time-dependent decrease in IOP (p < 0.05), while MEL alone failed to reduce IOP. However, both BRT and MEL reduced IOP in the presence of glaucoma at day 30 (p < 0.05). BRT treatment significantly reversed the reduced non-apoptotic RGC counts (p < 0.01) and increased TUNEL-positive RGCs (p < 0.001) to control group levels in the presence of glaucoma. However, no statistical significance was found between groups G and G + MEL considering 3% Fluorogold-labeled cell counts and apoptotic index values. CONCLUSION Our study revealed that systemic administration of BRT also has an IOP reducing effect. MEL has no neuroprotective effect on RGCs; on the other hand, BRT acts as a neuroprotective agent against glaucomatous injury, when applied systemically.
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Affiliation(s)
- Deniz Marangoz
- Department of Ophthalmology, Faculty of Medicine, Yeditepe University, Sakir Kesebir cad. Gazi Umur Pasa sok. No: 28, 34349, Beşiktaş-Istanbul, Turkey.
| | - Elif Guzel
- Department of Histology and Embryology, Cerrahpasa Faculty of Medicine, Istanbul University, Kocamustafapasa cad., 34098, Fatih-Istanbul, Turkey.
| | - Signem Eyuboglu
- Department of Physiology, Faculty of Medicine, Yeditepe University, Inonu mah. Kayisdagi cad. 26 Agustos Yerleskesi, 34755, Istanbul, Turkey
| | - Asli Gumusel
- Department of Histology and Embryology, Cerrahpasa Faculty of Medicine, Istanbul University, Kocamustafapasa cad., 34098, Fatih-Istanbul, Turkey
| | - Ismail Seckin
- Department of Histology and Embryology, Cerrahpasa Faculty of Medicine, Istanbul University, Kocamustafapasa cad., 34098, Fatih-Istanbul, Turkey
| | - Ferda Ciftci
- Department of Ophthalmology, Faculty of Medicine, Yeditepe University, Sakir Kesebir cad. Gazi Umur Pasa sok. No: 28, 34349, Beşiktaş-Istanbul, Turkey
| | - Bayram Yilmaz
- Department of Physiology, Faculty of Medicine, Yeditepe University, Inonu mah. Kayisdagi cad. 26 Agustos Yerleskesi, 34755, Istanbul, Turkey
| | - Ilgaz Yalvac
- Department of Ophthalmology, Faculty of Medicine, Yeditepe University, Sakir Kesebir cad. Gazi Umur Pasa sok. No: 28, 34349, Beşiktaş-Istanbul, Turkey
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Møller M, Rath MF, Ludvigsen M, Honoré B, Vorum H. Diurnal expression of proteins in the retina of the blind cone-rod homeobox (Crx -/- ) mouse and the 129/Sv mouse: a proteomic study. Acta Ophthalmol 2017; 95:717-726. [PMID: 28371363 DOI: 10.1111/aos.13429] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2016] [Accepted: 02/06/2017] [Indexed: 01/06/2023]
Abstract
PURPOSE The vertebrate retina contains a circadian clock participating in adaptations to day and night vision. This peripheral clock is independent of the master clock in the suprachiasmatic nucleus (SCN). The retinal clock is located in several cell types, including the photoreceptors. To investigate the role of the circadian clock of the photoreceptor cells in regulation of retinal protein rhythms, we analysed diurnal protein expression in the photoreceptor-deficient cone-rod homeobox knockout mouse (Crx-/- ) and the 129/Sv mouse. METHODS 2D gels were made from retinal homogenates of 129/Sv and Crx-/- mice killed at midday and midnight. Stained gels were analysed by use of PDQuest 2D gel analysis software. After trypsin digestion of differential expressed spots, the proteins were identified by LC-MS/MS using a nano-liquid chromatograph connected to a Q-TOF Premier mass spectrometer. These data were used to search the SWISS-PROT database. RESULTS Both the retinae of the control and the Crx-/- mice exhibited diurnal proteins rhythms. As expected, proteins involved in phototransduction were not detected in the Crx-/- mouse; in this phenotype, however, proteins from spots showing diurnal rhythms were specifically identified as enzymes involved in glucose metabolism, Krebs cycle, and mitochondrial enzymes. Data are available via ProteomeXchange with identifier PXD005556. CONCLUSION We show diurnal protein rhythms in the retina of a mouse lacking the rods and cones. The diurnal protein rhythms in this genotype, lacking the circadian clock of the photoreceptors, might be caused by a circadian clock in other retinal cell types or a direct light input to the retina.
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Affiliation(s)
- Morten Møller
- Department of Neuroscience and Pharmacology; Faculty of Health and Medical Sciences; University of Copenhagen; Copenhagen Denmark
| | - Martin Fredensborg Rath
- Department of Neuroscience and Pharmacology; Faculty of Health and Medical Sciences; University of Copenhagen; Copenhagen Denmark
| | - Maja Ludvigsen
- Department of Clinical Medicine; Aarhus University; Aarhus Denmark
- Department of Hematology; Aarhus University Hospital; Aarhus Denmark
| | - Bent Honoré
- Department of Biomedicine; Aarhus University; Aarhus Denmark
| | - Henrik Vorum
- Department of Ophthalmology; Aalborg University Hospital; Aalborg Denmark
- Department of Clinical Medicine; Aalborg University; Aalborg Denmark
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Sawant OB, Horton AM, Zucaro OF, Chan R, Bonilha VL, Samuels IS, Rao S. The Circadian Clock Gene Bmal1 Controls Thyroid Hormone-Mediated Spectral Identity and Cone Photoreceptor Function. Cell Rep 2017; 21:692-706. [PMID: 29045837 PMCID: PMC5647869 DOI: 10.1016/j.celrep.2017.09.069] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Revised: 08/15/2017] [Accepted: 09/20/2017] [Indexed: 10/18/2022] Open
Abstract
Circadian clocks regulate various aspects of photoreceptor physiology, but their contribution to photoreceptor development and function is unclear. Cone photoreceptors are critical for color vision. Here, we define the molecular function of circadian activity within cone photoreceptors and reveal a role for the clock genes Bmal1 and Per2 in regulating cone spectral identity. ChIP analysis revealed that BMAL1 binds to the promoter region of the thyroid hormone (TH)-activating enzyme type 2 iodothyronine deiodinase (Dio2) and thus regulates the expression of Dio2. TH treatment resulted in a partial rescue of the phenotype caused by the loss of Bmal1, thus revealing a functional relationship between Bmal1 and Dio2 in establishing cone photoreceptor identity. Furthermore, Bmal1 and Dio2 are required to maintain cone photoreceptor functional integrity. Overall, our results suggest a mechanism by which circadian proteins can locally regulate the availability of TH and influence tissue development and function.
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Affiliation(s)
- Onkar B Sawant
- Department of Ophthalmic Research, Cole Eye Institute, Cleveland Clinic, 9500 Euclid Avenue, Cleveland, OH 44195, USA
| | - Amanda M Horton
- Department of Ophthalmic Research, Cole Eye Institute, Cleveland Clinic, 9500 Euclid Avenue, Cleveland, OH 44195, USA
| | - Olivia F Zucaro
- Department of Ophthalmic Research, Cole Eye Institute, Cleveland Clinic, 9500 Euclid Avenue, Cleveland, OH 44195, USA
| | - Ricky Chan
- Institute for Computational Biology, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
| | - Vera L Bonilha
- Department of Ophthalmic Research, Cole Eye Institute, Cleveland Clinic, 9500 Euclid Avenue, Cleveland, OH 44195, USA; Department of Molecular Medicine, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH, USA
| | - Ivy S Samuels
- Department of Ophthalmic Research, Cole Eye Institute, Cleveland Clinic, 9500 Euclid Avenue, Cleveland, OH 44195, USA; Research Service, Louis Stokes Cleveland Veterans Affairs Medical Center, Cleveland, OH 44106, USA
| | - Sujata Rao
- Department of Ophthalmic Research, Cole Eye Institute, Cleveland Clinic, 9500 Euclid Avenue, Cleveland, OH 44195, USA; Department of Molecular Medicine, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH, USA.
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Kopperud KL, Grace MS. Circadian Rhythms of Retinomotor Movement in a Marine Megapredator, the Atlantic Tarpon, Megalops atlanticus. Int J Mol Sci 2017; 18:E2068. [PMID: 28956858 PMCID: PMC5666750 DOI: 10.3390/ijms18102068] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2017] [Revised: 09/21/2017] [Accepted: 09/21/2017] [Indexed: 11/16/2022] Open
Abstract
Many ecologically and economically important marine fish species worldwide spend portions of their lives in coastal regions that are increasingly inundated by artificial light at night. However, while extensive research illustrates the harmful effects of inappropriate light exposure on biological timing in humans, rodents and birds, comparable studies on marine fish are virtually nonexistent. This study aimed to assess the effects of light on biological clock function in the marine fish retina using the Atlantic tarpon (Megalops atlanticus) as a model. Using anti-opsin immunofluorescence, we observed robust rhythms of photoreceptor outer segment position (retinomotor movement) over the course of the daily light-dark cycle: cone outer segments were contracted toward the inner retina and rods were elongated during the day; the opposite occurred at night. Phase shifting the daily light-dark cycle caused a corresponding shift of retinomotor movement timing, and cone retinomotor movement persisted in constant darkness, indicating control by a circadian clock. Constant light abolished retinomotor movements of both photoreceptor types. Thus, abnormally-timed light exposure may disrupt normal M. atlanticus clock function and harm vision, which in turn may affect prey capture and predator avoidance. These results should help inform efforts to mitigate the effects of coastal light pollution on organisms in marine ecosystems.
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Affiliation(s)
- Kristin L Kopperud
- College of Science, Florida Institute of Technology, 150 West University Blvd, Melbourne, FL 32901, USA.
| | - Michael S Grace
- College of Science, Florida Institute of Technology, 150 West University Blvd, Melbourne, FL 32901, USA.
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Shi L, Ko ML, Ko GYP. Retinoschisin Facilitates the Function of L-Type Voltage-Gated Calcium Channels. Front Cell Neurosci 2017; 11:232. [PMID: 28848397 PMCID: PMC5550728 DOI: 10.3389/fncel.2017.00232] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Accepted: 07/25/2017] [Indexed: 11/18/2022] Open
Abstract
Modulation of ion channels by extracellular proteins plays critical roles in shaping synaptic plasticity. Retinoschisin (RS1) is an extracellular adhesive protein secreted from photoreceptors and bipolar cells, and it plays an important role during retinal development, as well as in maintaining the stability of retinal layers. RS1 is known to form homologous octamers and interact with molecules on the plasma membrane including phosphatidylserine, sodium-potassium exchanger complex, and L-type voltage-gated calcium channels (LTCCs). However, how this physical interaction between RS1 and ion channels might affect the channel gating properties is unclear. In retinal photoreceptors, two major LTCCs are Cav1.3 (α1D) and Cav1.4 (α1F) with distinct biophysical properties, functions and distributions. Cav1.3 is distributed from the inner segment (IS) to the synaptic terminal and is responsible for calcium influx to the photoreceptors and overall calcium homeostasis. Cav1.4 is only expressed at the synaptic terminal and is responsible for neurotransmitter release. Mutations of the gene encoding Cav1.4 cause X-linked incomplete congenital stationary night blindness type 2 (CSNB2), while null mutations of Cav1.3 cause a mild decrease of retinal light responses in mice. Even though RS1 is known to maintain retinal architecture, in this study, we present that RS1 interacts with both Cav1.3 and Cav1.4 and regulates their activations. RS1 was able to co-immunoprecipitate with Cav1.3 and Cav1.4 from porcine retinas, and it increased the LTCC currents and facilitated voltage-dependent activation in HEK cells co-transfected with RS1 and Cav1.3 or Cav1.4, thus providing evidence of a functional interaction between RS1 and LTCCs. The interaction between RS1 and Cav1.3 did not change the calcium-dependent inactivation of Cav1.3. In mice lacking RS1, the expression of Cav1.3 and Cav1.4 in the retina decreased, while in mice with Cav1.4 deletion, the retinal level of RS1 decreased. These results provide important evidence that RS1 is not only an adhesive protein promoting cell-cell adhesion, it is essential for anchoring other membrane proteins including ion channels and enhancing their function in the retina.
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Affiliation(s)
- Liheng Shi
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M UniversityCollege Station, TX, United States
| | - Michael L Ko
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M UniversityCollege Station, TX, United States
| | - Gladys Y-P Ko
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M UniversityCollege Station, TX, United States.,Texas A&M Institute for Neuroscience, Texas A&M UniversityCollege Station, TX, United States
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Backlund PS, Urbanski HF, Doll MA, Hein DW, Bozinoski M, Mason CE, Coon SL, Klein DC. Daily Rhythm in Plasma N-acetyltryptamine. J Biol Rhythms 2017; 32:195-211. [PMID: 28466676 PMCID: PMC5571864 DOI: 10.1177/0748730417700458] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Normal physiology undergoes 24-h changes in function that include daily rhythms in circulating hormones, most notably melatonin and cortical steroids. This study focused on N-acetyltryptamine, a little-studied melatonin receptor mixed agonist-antagonist and the likely evolutionary precursor of melatonin. The central issue addressed was whether N-acetyltryptamine is physiologically present in the circulation. N-acetyltryptamine was detected by LC-MS/MS in daytime plasma of 3 different mammals in subnanomolar levels (mean ± SEM: rat, 0.29 ± 0.05 nM, n = 5; rhesus macaque, 0.54 ± 0.24 nM, n = 4; human, 0.03 ± 0.01 nM, n = 32). Analysis of 24-h blood collections from rhesus macaques revealed a nocturnal increase in plasma N-acetyltryptamine (p < 0.001), which varied from 2- to 15-fold over daytime levels among the 4 animals studied. Related RNA sequencing studies indicated that the transcript encoding the tryptamine acetylating enzyme arylalkylamine N-acetyltransferase (AANAT) is expressed at similar levels in the rhesus pineal gland and retina, thereby indicating that either tissue could contribute to circulating N-acetyltryptamine. The evidence that N-acetyltryptamine is a physiological component of mammalian blood and exhibits a daily rhythm, together with known effects as a melatonin receptor mixed agonist-antagonist, shifts the status of N-acetyltryptamine from pharmacological tool to candidate for a physiological role. This provides a new opportunity to extend our understanding of 24-h biology.
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Affiliation(s)
- Peter S. Backlund
- Biomedical Mass Spectrometry Facility, Intramural Research Program,
Eunice Kennedy Shriver National Institute of Child Health and
Human Development, National Institutes of Health, Bethesda, MD 20892-1580
| | - Henryk F. Urbanski
- Division of Neuroscience, Oregon National Primate Research Center,
Beaverton, OR 97006
- Division of Reproductive and Developmental Sciences, Oregon National
Primate Research Center, Beaverton, OR 97006
- Department of Behavioral Neuroscience, Oregon Health and Science
University, Portland, OR 97006
- Department of Physiology and Pharmacology, Oregon Health and Science
University, Portland, OR 97239
| | - Mark A. Doll
- Department of Pharmacology and Toxicology, and James Graham Brown
Cancer Center, University of Louisville, Louisville, KY 40202
| | - David W. Hein
- Department of Pharmacology and Toxicology, and James Graham Brown
Cancer Center, University of Louisville, Louisville, KY 40202
| | - Marjan Bozinoski
- Department of Physiology and Biophysics, Weill Cornell Medical
College, Cornell University, New York, NY 10065
| | - Christopher E. Mason
- Department of Physiology and Biophysics, Weill Cornell Medical
College, Cornell University, New York, NY 10065
- The HRH Prince Alwaleed Bin Talal Bin Abdulaziz Alsaud Institute for
Computational Biomedicine, Weill Cornell Medicine, New York, NY, USA
- The Feil Family Brain and Mind Research Institute, Weill Cornell
Medicine, New York, NY, USA
| | - Steven L. Coon
- Section on Neuroendocrinology, Program in Developmental
Endocrinology and Genetics, Eunice Kennedy Shriver National
Institute of Child Health and Human Development, National Institutes of Health,
Bethesda, MD 20892-1830
- Molecular Genomics Core Facility, Office of the Scientific
Director, Eunice Kennedy Shriver National Institute of Child Health
and Human Development, National Institutes of Health, Bethesda, MD 20892-1830
| | - David C. Klein
- Section on Neuroendocrinology, Program in Developmental
Endocrinology and Genetics, Eunice Kennedy Shriver National
Institute of Child Health and Human Development, National Institutes of Health,
Bethesda, MD 20892-1830
- Office of the Scientific Director, Intramural Research Program,
Eunice Kennedy Shriver National Institute of Child Health and
Human Development, National Institutes of Health, Bethesda, MD 20892-1830
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Zelinsky D, Feinberg C. Quantitative electroencephalograms and neuro-optometry: a case study that explores changes in electrophysiology while wearing therapeutic eyeglasses. NEUROPHOTONICS 2017; 4:011013. [PMID: 28386574 PMCID: PMC5350544 DOI: 10.1117/1.nph.4.1.011013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Accepted: 02/24/2017] [Indexed: 05/07/2023]
Abstract
The brain is equipped with a complex system for processing sensory information, including retinal circuitry comprising part of the central nervous system. Retinal stimulation can influence brain function via customized eyeglasses at both subcortical and cortical levels. We investigated cortical effects from wearing therapeutic eyeglasses, hypothesizing that they can create measureable changes in electroencephalogram (EEG) tracings. A Z-BellSM test was performed on a participant to select optimal lenses. An EEG measurement was recorded before and after the participant wore the eyeglasses. Equivalent quantitative electroencephalography (QEEG) analyses (statistical analysis on raw EEG recordings) were performed and compared with baseline findings. With glasses on, the participant's readings were found to be closer to the normed database. The original objective of our investigation was met, and additional findings were revealed. The Z-bellSM test identified lenses to influence neurotypical brain activity, supporting the paradigm that eyeglasses can be utilized as a therapeutic intervention. Also, EEG analysis demonstrated that encephalographic techniques can be used to identify channels through which neuro-optomertric treatments work. This case study's preliminary exploration illustrates the potential role of QEEG analysis and EEG-derived brain imaging in neuro-optometric research endeavors to affect brain function.
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Affiliation(s)
- Deborah Zelinsky
- The Mind-Eye Connection, Northbrook, Illinois, United States
- Address all correspondence to: Deborah Zelinsky, E-mail:
| | - Corey Feinberg
- Meridian Behavioral Health Services, Northbrook, Illinois, United States
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Vancura P, Wolloscheck T, Baba K, Tosini G, Iuvone PM, Spessert R. Circadian and Dopaminergic Regulation of Fatty Acid Oxidation Pathway Genes in Retina and Photoreceptor Cells. PLoS One 2016; 11:e0164665. [PMID: 27727308 PMCID: PMC5058478 DOI: 10.1371/journal.pone.0164665] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Accepted: 09/28/2016] [Indexed: 12/17/2022] Open
Abstract
The energy metabolism of the retina might comply with daily changes in energy demand and is impaired in diabetic retinopathy-one of the most common causes of blindness in Europe and the USA. The aim of this study was to investigate putative adaptation of energy metabolism in healthy and diabetic retina. Hence expression analysis of metabolic pathway genes was performed using quantitative polymerase chain reaction, semi-quantitative western blot and immunohistochemistry. Transcriptional profiling of key enzymes of energy metabolism identified transcripts of mitochondrial fatty acid β-oxidation enzymes, i.e. carnitine palmitoyltransferase-1α (Cpt-1α) and medium chain acyl-CoA dehydrogenase (Acadm) to display daily rhythms with peak values during daytime in preparations of the whole retina and microdissected photoreceptors. The cycling of both enzymes persisted in constant darkness, was dampened in mice deficient for dopamine D4 (D4) receptors and was altered in db/db mice-a model of diabetic retinopathy. The data of the present study are consistent with circadian clock-dependent and dopaminergic regulation of fatty acid oxidation in retina and its putative disturbance in diabetic retina.
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MESH Headings
- Acyl-CoA Dehydrogenase/genetics
- Acyl-CoA Dehydrogenase/metabolism
- Animals
- Carnitine O-Palmitoyltransferase/genetics
- Carnitine O-Palmitoyltransferase/metabolism
- Circadian Rhythm/physiology
- Diabetic Retinopathy/metabolism
- Diabetic Retinopathy/pathology
- Disease Models, Animal
- Dopamine/metabolism
- Energy Metabolism
- Fatty Acids/chemistry
- Fatty Acids/metabolism
- Female
- Male
- Mice
- Mice, Inbred C3H
- Mice, Inbred C57BL
- Mice, Knockout
- Mice, Obese
- Microscopy, Fluorescence
- Oxidation-Reduction
- Photoreceptor Cells/metabolism
- Receptor, Melatonin, MT1/deficiency
- Receptor, Melatonin, MT1/genetics
- Receptors, Dopamine D4/deficiency
- Receptors, Dopamine D4/genetics
- Retina/metabolism
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Affiliation(s)
- Patrick Vancura
- Institute of Functional and Clinical Anatomy, University Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Tanja Wolloscheck
- Institute of Functional and Clinical Anatomy, University Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Kenkichi Baba
- Neuroscience Institute and Department of Pharmacology and Toxicology, Morehouse School of Medicine, Atlanta, Georgia, United States of America
| | - Gianluca Tosini
- Neuroscience Institute and Department of Pharmacology and Toxicology, Morehouse School of Medicine, Atlanta, Georgia, United States of America
| | - P. Michael Iuvone
- Department of Ophthalmology, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Rainer Spessert
- Institute of Functional and Clinical Anatomy, University Medical Center of the Johannes Gutenberg University, Mainz, Germany
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Jadhav V, Luo Q, M. Dominguez J, Al-Sabah J, Chaqour B, Grant MB, Bhatwadekar AD. Per2-Mediated Vascular Dysfunction Is Caused by the Upregulation of the Connective Tissue Growth Factor (CTGF). PLoS One 2016; 11:e0163367. [PMID: 27662578 PMCID: PMC5035004 DOI: 10.1371/journal.pone.0163367] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Accepted: 09/07/2016] [Indexed: 01/08/2023] Open
Abstract
Period 2-mutant mice (Per2m/m), which possess a circadian dysfunction, recapitulate the retinal vascular phenotype similar to diabetic retinopathy (DR). The vascular dysfunction in Per2m/m is associated with an increase in connective tissue growth factor (CTGF/CCN2). At the molecular level, CTGF gene expression is dependent on the canonical Wnt/β-catenin pathway. The nuclear binding of β-catenin to a transcription factor, lymphoid enhancer binding protein (Lef)/ T-cell factor (TCF/LEF), leads to downstream activation of CTGF. For this study, we hypothesized that the silencing of Per2 results in nuclear translocation and subsequent transactivation of the CTGF gene. To test this hypothesis, we performed immunofluorescence labeling for CTGF in retinal sections from wild-type (WT) and Per2m/m mice. Human retinal endothelial cells (HRECs) were transfected with siRNA for Per2, and the protein expression of CTGF and β-catenin was evaluated. The TCF/LEF luciferase reporter (TOPflash) assay was performed to validate the involvement of β-catenin in the activation of CTGF. Per2m/m retinas exhibited an increased CTGF immunostaining in ganglion cell layer and retinal endothelium. Silencing of Per2 using siRNA resulted in an upregulation of CTGF and β-catenin. The TOPflash assay revealed an increase in luminescence for HRECs transfected with Per2 siRNA. Our studies show that loss of Per2 results in an activation of CTGF via nuclear entry of β-catenin. Our study provides novel insight into the understanding of microvascular dysfunction in Per2m/m mice.
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Affiliation(s)
- Vaishnavi Jadhav
- Department of Ophthalmology, Eugene and Marilyn Glick Eye Institute, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Qianyi Luo
- Department of Ophthalmology, Eugene and Marilyn Glick Eye Institute, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - James M. Dominguez
- Department of Ophthalmology, Eugene and Marilyn Glick Eye Institute, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Jude Al-Sabah
- Department of Ophthalmology, Eugene and Marilyn Glick Eye Institute, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Brahim Chaqour
- Department of Cell Biology, Suny Downstate Medical Center, Brooklyn, New York, United States of America
| | - Maria B. Grant
- Department of Ophthalmology, Eugene and Marilyn Glick Eye Institute, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Ashay D. Bhatwadekar
- Department of Ophthalmology, Eugene and Marilyn Glick Eye Institute, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
- * E-mail:
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Melatonin in Retinal Physiology and Pathology: The Case of Age-Related Macular Degeneration. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2016; 2016:6819736. [PMID: 27688828 PMCID: PMC5027321 DOI: 10.1155/2016/6819736] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Accepted: 08/09/2016] [Indexed: 12/16/2022]
Abstract
Melatonin, an indoleamine, is synthesized mainly in the pineal gland in a circadian fashion, but it is produced in many other organs, including the retina, which seems to be especially important as the eye is a primary recipient of circadian signals. Melatonin displays strong antioxidative properties, which predispose it to play a protective role in many human pathologies associated with oxidative stress, including premature aging and degenerative disease. Therefore, melatonin may play a role in age-related macular degeneration (AMD), a disease affecting photoreceptors, and retinal pigment epithelium (RPE) with an established role of oxidative stress in its pathogenesis. Several studies have shown that melatonin could exert the protective effect against damage to RPE cells evoked by reactive oxygen species (ROS), but it has also been reported to increase ROS-induced damage to photoreceptors and RPE. Melatonin behaves like synthetic mitochondria-targeted antioxidants, which concentrate in mitochondria at relatively high levels; thus, melatonin may prevent mitochondrial damage in AMD. The retina contains telomerase, an enzyme implicated in maintaining the length of telomeres, and oxidative stress inhibits telomere synthesis, while melatonin overcomes this effect. These features support considering melatonin as a preventive and therapeutic agent in the treatment of AMD.
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The Shift of ERG B-Wave Induced by Hours' Dark Exposure in Rodents. PLoS One 2016; 11:e0161010. [PMID: 27517462 PMCID: PMC4982619 DOI: 10.1371/journal.pone.0161010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2016] [Accepted: 07/28/2016] [Indexed: 11/29/2022] Open
Abstract
Purpose Dark adaptation can induce a rapid functional shift in the retina, and after that, the retinal function is believed to remain stable during the continuous dark exposure. However, we found that electroretinograms (ERG) b-waves gradually shifted during 24 hours’ dark exposure in rodents. Detailed experiments were designed to explore this non-classical dark adaptation. Methods In vivo ERG recording in adult and developing rodents after light manipulations. Results We revealed a five-fold decrease in ERG b-waves in adult rats that were dark exposed for 24 hours. The ERG b-waves significantly increased within the first hour’s dark exposure, but after that decreased continuously and finally attained steady state after 1 day’s dark exposure. After 3 repetitive, 10 minutes’ light exposure, the dark exposed rats fully recovered. This recovery effect was eye-specific, and light exposure to one eye could not restore the ERGs in the non-exposed eye. The prolonged dark exposure-induced functional shift was also reflected in the down-regulation on the amplitude of intensity-ERG response curve, but the dynamic range of the responsive light intensity remained largely stable. Furthermore, the ERG b-wave shifts occurred in and beyond classical critical period, and in both rats and mice. Importantly, when ERG b-wave greatly shifted, the amplitude of ERG a-wave did not change significantly after the prolonged dark exposure. Conclusions This rapid age-independent ERG change demonstrates a generally existing functional shift in the retina, which is at the entry level of visual system.
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Aydin E, Sahin S. Increased melatonin levels in aqueous humor of patients with proliferative retinopathy in type 2 diabetes mellitus. Int J Ophthalmol 2016; 9:721-4. [PMID: 27275429 DOI: 10.18240/ijo.2016.05.15] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2014] [Accepted: 10/13/2015] [Indexed: 11/23/2022] Open
Abstract
AIM To report the association between melatonin levels in aqueous humor and serum, and diabetic retinopathy (DR) grade in type 2 diabetic patients. METHODS Aqueous humor and plasma samples from 26 patients with DR (in nonproliferative and proliferative stages) and 14 control subjects were collected during cataract surgery after 6 p.m. Melatonin concentrations were determined using an enzyme-linked immunosorbent assay (ELISA). RESULTS Melatonin levels were significantly higher in the aqueous humor of patients with proliferative diabetic retinopathy (PDR) [18.57±2.67 pg/mL (range 15.20-23.06) vs 13.63±2.71 pg/mL (range 10.20-20.20), P=0.0001], but not in those with nonproliferative retinopathy (NPDR) [13.79±2.56 pg/mL (range 9.80-20.10) vs 13.63±2.71 pg/mL (range 10.20-20.20), P=0.961] compared to controls. There was decrement in the plasma melatonin level of patients with PDR, but no significant differences between the plasma melatonin levels of the study groups [5.37±1.74 pg/mL (range 2.85-8.65) vs 6.11±1.90 pg/mL (range 3.13-9.41), P=0.293], or between control and DR groups [NPDR 6.11±1.90 pg/mL (range 3.13-9.41) vs control 6.15±1.91 pg/mL (range 2.18-9.86); PDR (5.37±1.74 pg/mL (range 2.85-8.65) vs control 6.15±1.91 pg/mL (range 2.18-9.86), P=0.808, P=0.264]. CONCLUSION Elevated melatonin levels in aqueous humor in PDR may indicate the level to be associated with DR severity.
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Affiliation(s)
- Erdinc Aydin
- Izmir Katip Celebi University, Faculty of Medicine, Ophthalmology, Izmir 35620, Turkey
| | - Semsettin Sahin
- Gaziosmanpasa University Faculty of Medicine, Biochemistry, Tokat 60250, Turkey
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