1
|
Bejarano E, Domenech-Bendaña A, Avila-Portillo N, Rowan S, Edirisinghe S, Taylor A. Glycative stress as a cause of macular degeneration. Prog Retin Eye Res 2024; 101:101260. [PMID: 38521386 DOI: 10.1016/j.preteyeres.2024.101260] [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: 01/05/2024] [Revised: 03/08/2024] [Accepted: 03/11/2024] [Indexed: 03/25/2024]
Abstract
People are living longer and rates of age-related diseases such as age-related macular degeneration (AMD) are accelerating, placing enormous burdens on patients and health care systems. The quality of carbohydrate foods consumed by an individual impacts health. The glycemic index (GI) is a kinetic measure of the rate at which glucose arrives in the blood stream after consuming various carbohydrates. Consuming diets that favor slowly digested carbohydrates releases sugar into the bloodstream gradually after consuming a meal (low glycemic index). This is associated with reduced risk for major age-related diseases including AMD, cardiovascular disease, and diabetes. In comparison, consuming the same amounts of different carbohydrates in higher GI diets, releases glucose into the blood rapidly, causing glycative stress as well as accumulation of advanced glycation end products (AGEs). Such AGEs are cytotoxic by virtue of their forming abnormal proteins and protein aggregates, as well as inhibiting proteolytic and other protective pathways that might otherwise selectively recognize and remove toxic species. Using in vitro and animal models of glycative stress, we observed that consuming higher GI diets perturbs metabolism and the microbiome, resulting in a shift to more lipid-rich metabolomic profiles. Interactions between aging, diet, eye phenotypes and physiology were observed. A large body of laboratory animal and human clinical epidemiologic data indicates that consuming lower GI diets, or lower glycemia diets, is protective against features of early AMD (AMDf) in mice and AMD prevalence or AMD progression in humans. Drugs may be optimized to diminish the ravages of higher glycemic diets. Human trials are indicated to determine if AMD progression can be retarded using lower GI diets. Here we summarized the current knowledge regarding the pathological role of glycative stress in retinal dysfunction and how dietary strategies might diminish retinal disease.
Collapse
Affiliation(s)
- Eloy Bejarano
- Department of Biomedical Sciences, School of Health Sciences and Veterinary School, Universidad Cardenal Herrera-CEU, CEU Universities, Valencia, Spain
| | - Alicia Domenech-Bendaña
- Department of Biomedical Sciences, School of Health Sciences and Veterinary School, Universidad Cardenal Herrera-CEU, CEU Universities, Valencia, Spain
| | | | - Sheldon Rowan
- JM USDA Human Nutrition Research Center on Aging at Tufts University, United States
| | - Sachini Edirisinghe
- Tufts University Friedman School of Nutrition Science and Policy, United States
| | - Allen Taylor
- Tufts University Friedman School of Nutrition Science and Policy, United States.
| |
Collapse
|
2
|
Feng L, Nie K, Huang Q, Fan W. Complement factor H deficiency combined with smoking promotes retinal degeneration in a novel mouse model. Exp Biol Med (Maywood) 2021; 247:77-86. [PMID: 34775843 DOI: 10.1177/15353702211052245] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Age-related macular degeneration is the leading cause of blindness in the elderly. The Y402H polymorphism in complement factor H promotes disease-like pathogenesis, and a Cfh+/- murine model can replicate this phenotype, but only after two years. We reasoned that by combining CFH deficiency with cigarette smoke exposure, we might be able to accelerate disease progression to facilitate preclinical research in this disease. Wild-type and Cfh+/- mice were exposed to nose-only cigarette smoke for three months. Retinal tissue morphology and visual function were evaluated by optical coherence tomography, fundus photography and autofluorescence, and electroretinogram. Retinal pigment epithelial cell phenotype and ultrastructure were evaluated by immunofluorescence staining and transmission electron microscopy. Cfh+/- smoking mice showed a dome-like protruding lesion at the ellipsoid zone (drusen-like deposition), many retinal hyper-autofluorescence spots, and a marked decrease in A- and B-wave amplitudes. Compared with non-smoking mice, wild-type and Cfh+/- smoking mice showed sub-retinal pigment epithelium complement protein 3 deposition, activation of microglia, metabolic waste accumulation, and impairment of tight junctions. Microglia cells migrated into the photoreceptor outer segment layer in Cfh+/- smoking mice showed increased activation. Our results suggest that exposing Cfh+/- mice to smoking leads to earlier onset of age-related macular degeneration than in other animal models, which may facilitate preclinical research into the pathophysiology and treatment of this disease.
Collapse
Affiliation(s)
- Liwen Feng
- Department of Ophthalmology, West China Hospital of Sichuan University, Chengdu 610041, China.,Research Laboratory of Ophthalmology and Vision Sciences, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu 610041, China
| | - Kailai Nie
- Department of Ophthalmology, West China Hospital of Sichuan University, Chengdu 610041, China.,Research Laboratory of Ophthalmology and Vision Sciences, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu 610041, China
| | - Qing Huang
- Department of Ophthalmology, West China Hospital of Sichuan University, Chengdu 610041, China
| | - Wei Fan
- Department of Ophthalmology, West China Hospital of Sichuan University, Chengdu 610041, China
| |
Collapse
|
3
|
Soundara Pandi SP, Ratnayaka JA, Lotery AJ, Teeling JL. Progress in developing rodent models of age-related macular degeneration (AMD). Exp Eye Res 2020; 203:108404. [PMID: 33340497 DOI: 10.1016/j.exer.2020.108404] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 12/13/2020] [Accepted: 12/14/2020] [Indexed: 12/25/2022]
Abstract
Age-related macular degeneration (AMD) is the leading cause of irreversible central vision loss, typically affecting individuals from mid-life onwards. Its multifactorial aetiology and the lack of any effective treatments has spurred the development of animal models as research and drug discovery tools. Several rodent models have been developed which recapitulate key features of AMD and provide insights into its underlying pathology. These have contributed to making significant progress in understanding the disease and the identification of novel therapeutic targets. However, a major caveat with existing models is that they do not demonstrate the full disease spectrum. In this review, we outline advances in rodent AMD models from the last decade. These models feature various hallmarks associated with AMD, including oxidative stress, hypoxia, immune dysregulation, genetic mutations and environmental risk factors. The review summarises the methods by which each model was created, its pathological characteristics as well as its relation to the disease in humans.
Collapse
Affiliation(s)
- Sudha Priya Soundara Pandi
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, MP806, Tremona Road, Southampton, SO16 6YD, United Kingdom
| | - J Arjuna Ratnayaka
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, MP806, Tremona Road, Southampton, SO16 6YD, United Kingdom.
| | - Andrew J Lotery
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, MP806, Tremona Road, Southampton, SO16 6YD, United Kingdom; Eye Unit, University Hospital Southampton NHS Foundation Trust, Southampton, SO16 6YD, United Kingdom.
| | - Jessica L Teeling
- Biological Sciences, Faculty of Natural and Environmental Sciences, University of Southampton, MP840, Tremona Road, Southampton, SO16 6YD, United Kingdom.
| |
Collapse
|
4
|
Rowan S, Jiang S, Chang ML, Volkin J, Cassalman C, Smith KM, Streeter MD, Spiegel DA, Moreira-Neto C, Rabbani N, Thornalley PJ, Smith DE, Waheed NK, Taylor A. A low glycemic diet protects disease-prone Nrf2-deficient mice against age-related macular degeneration. Free Radic Biol Med 2020; 150:75-86. [PMID: 32068111 PMCID: PMC7747150 DOI: 10.1016/j.freeradbiomed.2020.02.010] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Revised: 01/30/2020] [Accepted: 02/12/2020] [Indexed: 12/16/2022]
Abstract
Age-related macular degeneration (AMD) is a major blinding disease, affecting over 14% of the elderly. Risk for AMD is related to age, diet, environment, and genetics. Dietary modulation of AMD risk is a promising treatment modality, but requires appropriate animal models to demonstrate advantages of diet. Mice lacking the antioxidant transcription factor Nrf2 (Nfe2l2) develop age-related retinopathy relevant to human AMD. Here we evaluated the effect of consuming high glycemic (HG) or low glycemic (LG) diets until 18-months of age on development of features relevant to AMD in Nrf2-null mice. Nrf2-null mice that consumed HG diets developed atrophic AMD, characterized by photoreceptor degeneration, retinal pigment epithelium (RPE) atrophy and pigmentary abnormalities, basal laminar deposits, and loss of the choriocapillaris. In contrast, Nrf2-null-mice that consumed LG diets did not develop retinal disease phenotypes. Consumption of HG diets was associated with accumulation of advanced glycation end-products in the RPE and systemically, whereas consumption of the LG diet was associated with increased levels of anti-glycative and anti-oxidative detoxification machinery. Together our data indicate that the Nrf2-null HG mouse is a good model for atrophic AMD studies and that the LG diet can activate protective pathways to prevent AMD, even in a genetically predisposed animal.
Collapse
Affiliation(s)
- Sheldon Rowan
- Laboratory for Nutrition and Vision Research, JM-USDA Human Nutrition Research Center on Aging, Tufts University, Boston, MA, 02111, USA; Friedman School of Nutrition and Science Policy, Tufts University, Boston, MA, 02111, USA; Department of Ophthalmology, Tufts University School of Medicine, Boston, MA, 02111, USA.
| | - Shuhong Jiang
- Laboratory for Nutrition and Vision Research, JM-USDA Human Nutrition Research Center on Aging, Tufts University, Boston, MA, 02111, USA; Inner Mongolia Autonomous Region People's Hospital, Hohhot, Inner Mongolia, 010017, China
| | - Min-Lee Chang
- Laboratory for Nutrition and Vision Research, JM-USDA Human Nutrition Research Center on Aging, Tufts University, Boston, MA, 02111, USA
| | - Jonathan Volkin
- Laboratory for Nutrition and Vision Research, JM-USDA Human Nutrition Research Center on Aging, Tufts University, Boston, MA, 02111, USA
| | - Christa Cassalman
- Department of Pathology and Laboratory Medicine, Tufts University School of Medicine, Boston, MA, 02111, USA
| | - Kelsey M Smith
- Laboratory for Nutrition and Vision Research, JM-USDA Human Nutrition Research Center on Aging, Tufts University, Boston, MA, 02111, USA; Friedman School of Nutrition and Science Policy, Tufts University, Boston, MA, 02111, USA
| | | | - David A Spiegel
- Department of Chemistry, Yale University, New Haven, CT, 06520, USA
| | - Carlos Moreira-Neto
- Department of Ophthalmology, Tufts University School of Medicine, Boston, MA, 02111, USA
| | - Naila Rabbani
- Clinical Sciences Research Laboratories, Warwick Medical School, University of Warwick, University Hospital, Coventry, CV2 2DX, UK; Department of Basic Medical Sciences, College of Medicine, QU Health, Qatar University, P.O. Box 2713, Doha, Qatar
| | - Paul J Thornalley
- Clinical Sciences Research Laboratories, Warwick Medical School, University of Warwick, University Hospital, Coventry, CV2 2DX, UK; Diabetes Research Center, Qatar Biomedical Research Institute, Hamad Bin Khalifa University, Qatar Foundation, P.O. Box 34110, Doha, Qatar
| | - Donald E Smith
- Laboratory for Nutrition and Vision Research, JM-USDA Human Nutrition Research Center on Aging, Tufts University, Boston, MA, 02111, USA
| | - Nadia K Waheed
- Department of Ophthalmology, Tufts University School of Medicine, Boston, MA, 02111, USA
| | - Allen Taylor
- Laboratory for Nutrition and Vision Research, JM-USDA Human Nutrition Research Center on Aging, Tufts University, Boston, MA, 02111, USA; Friedman School of Nutrition and Science Policy, Tufts University, Boston, MA, 02111, USA; Department of Ophthalmology, Tufts University School of Medicine, Boston, MA, 02111, USA.
| |
Collapse
|
5
|
Zhu Y, Aredo B, Chen B, Zhao CX, He YG, Ufret-Vincenty RL. Mice With a Combined Deficiency of Superoxide Dismutase 1 (Sod1), DJ-1 (Park7), and Parkin (Prkn) Develop Spontaneous Retinal Degeneration With Aging. Invest Ophthalmol Vis Sci 2020; 60:3740-3751. [PMID: 31487745 PMCID: PMC6733419 DOI: 10.1167/iovs.19-27212] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose Chronic oxidative stress is an important mechanism of disease in aging disorders. We do not have a good model to recapitulate AMD and other retinal disorders in which chronic oxidative stress plays an important role. We hypothesized that mice with a combined deficiency in superoxide dismutase 1 (Sod1), DJ-1 (Park-7), and Parkin (Prkn) (triple knock out, TKO) would have an increased level of chronic oxidative stress in the retina, with anatomic and functional consequences just with aging. Methods Eyes of TKO and B6J control mice were (1) monitored with optical coherence tomography (OCT) and electroretinography (ERG) over time, and (2) collected for oxidative marker protein analysis by ELISA or immunohistochemistry and for transmission electron microscopy studies. Results TKO mice developed qualitative disruptions in outer retinal layers in OCT by 3 months, increased accumulation of fundus spots and subretinal microglia by 6 months of age, significant retinal thinning by 9 months, and decreased ERG signal by 12 months. Furthermore, we found increased accumulation of the oxidative marker malondialdehyde (MDA) in the retina and increased basal laminal deposits (BLD) and mitochondria number and size in the retinal pigment epithelium of aging TKO mice. Conclusions TKO mice can serve as a platform to study retinal diseases that involve chronic oxidative stress, including macular degeneration, retinal detachment, and ischemic retinopathies. In order to model each of these diseases, additional disease-specific catalysts or triggers could be superimposed onto the TKO mice. Such studies could provide better insight into disease mechanisms and perhaps lead to new therapeutic approaches.
Collapse
Affiliation(s)
- Yuanfei Zhu
- Department of Ophthalmology, UT Southwestern Medical Center, Dallas, Texas, United States
| | - Bogale Aredo
- Department of Ophthalmology, UT Southwestern Medical Center, Dallas, Texas, United States
| | - Bo Chen
- Department of Ophthalmology, UT Southwestern Medical Center, Dallas, Texas, United States
| | - Cynthia X Zhao
- Department of Ophthalmology, UT Southwestern Medical Center, Dallas, Texas, United States
| | - Yu-Guang He
- Department of Ophthalmology, UT Southwestern Medical Center, Dallas, Texas, United States
| | | |
Collapse
|
6
|
Bejarano E, Taylor A. Too sweet: Problems of protein glycation in the eye. Exp Eye Res 2019; 178:255-262. [PMID: 30145354 PMCID: PMC8351608 DOI: 10.1016/j.exer.2018.08.017] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Revised: 08/03/2018] [Accepted: 08/22/2018] [Indexed: 01/06/2023]
Abstract
Laboratory and epidemiological data indicate that high blood sugar levels and/or consuming high glycemia diets are linked to multiple age-related diseases, including age-related macular degeneration, cataract, Parkinson's disease, Alzheimer's disease, diabetic retinopathy, and, apparently glaucoma. High concentrations of blood sugar and perturbations of the systems that regulate blood sugar lead to the accumulation of advanced-glycation end products (AGEs). AGEs are toxic compounds that are formed from the combination of sugars and their metabolites with biomolecules in a non-enzymatic biochemical reaction called glycation. In vitro and in vivo data indicate that high sugar consumption is associated with accumulation of AGEs in a variety of human tissues. Hyperglycemia, along with an oxidative environment and limited cell proliferation in many ocular tissues, encourages formation and precludes dilution of AGEs and associated damage by cell division. These circumstances make many eye tissues vulnerable to glycation-derived damage. Here, we summarize research regarding glycation-induced ocular tissue dysfunction and its contribution to the onset and development of eye disorders. We also discuss how management of carbohydrate nutrition may provide a low-cost way to ameliorate the progression of AGEs-related diseases, including age related macular degeneration and some cataracts, as they do for cardiovascular disease and diabetes.
Collapse
Affiliation(s)
- Eloy Bejarano
- Laboratory for Nutrition and Vision Research, USDA Human Nutrition Research Center on Aging, Tufts University, 711 Washington St, Boston, MA, 02111, USA.
| | - Allen Taylor
- Laboratory for Nutrition and Vision Research, USDA Human Nutrition Research Center on Aging, Tufts University, 711 Washington St, Boston, MA, 02111, USA.
| |
Collapse
|
7
|
Adipocytes and intestinal epithelium dysfunctions linking obesity to inflammation induced by high glycemic index pellet-diet in Wistar rats. Biosci Rep 2018; 38:BSR20180304. [PMID: 29950343 PMCID: PMC6019358 DOI: 10.1042/bsr20180304] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Revised: 04/07/2018] [Accepted: 04/16/2018] [Indexed: 12/14/2022] Open
Abstract
We investigated the inflammatory effect of a pellet-diet with high glycemic index and load (HGLI) on the histological organization of adipocytes, intestinal epithelium, and fat in liver and pancreas in adult male Wistar rats. Two groups (n=10) received for 17 weeks: (1) HGLI diet or (2) Standard diet (Labina®). Histological analyses of adipose tissue, jejunum, liver, and pancreas were performed. Stereology analysis, visceral adiposity index, gene expression, and immunohistochemistry of tumor necrosis factor-α (TNF-α) in visceral adipose tissue and plasma TNF-α were also assessed. The HGLI diet-induced hypertrophy of adipocytes with adipocyte volume density equal to 97.0%, cross-sectional area of adipocytes equivalent to 1387 µm² and a total volume of adipocytes of 6.97 cm³ an elevation of 8%, 25%, and 58%, respectively. Furthermore, the HGLI diet increased liver and pancreatic fat deposition, altered and inflamed the intestinal epithelia, and increased TNF-α gene expression (P=0.014) with a positive immunostaining in visceral adipose tissue and high plasma TNF-α in comparison with standard diet. The results suggest that this diet was able to generate changes commonly caused to solid diets with high fat or fructose-rich beverages. To the best of our knowledge, this is the first report in the literature concerning the properties of low-cost, sucrose-rich pellet-diet presenting high glycemic index and high glycemic load efficient on the development of obesity complications in Wistar rats that were subjected to diet-induced obesity. Therefore, the HGLI pellet-diet may be considered an effective tool to be used by the scientific community in experimental research.
Collapse
|
8
|
Rathnasamy G, Foulds WS, Ling EA, Kaur C. Retinal microglia - A key player in healthy and diseased retina. Prog Neurobiol 2018; 173:18-40. [PMID: 29864456 DOI: 10.1016/j.pneurobio.2018.05.006] [Citation(s) in RCA: 127] [Impact Index Per Article: 21.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Revised: 03/09/2018] [Accepted: 05/29/2018] [Indexed: 01/04/2023]
Abstract
Microglia, the resident immune cells of the brain and retina, are constantly engaged in the surveillance of their surrounding neural tissue. During embryonic development they infiltrate the retinal tissues and participate in the phagocytosis of redundant neurons. The contribution of microglia in maintaining the purposeful and functional histo-architecture of the adult retina is indispensable. Within the retinal microenvironment, robust microglial activation is elicited by subtle changes caused by extrinsic and intrinsic factors. When there is a disturbance in the cell-cell communication between microglia and other retinal cells, for example in retinal injury, the activated microglia can manifest actions that can be detrimental. This is evidenced by activated microglia secreting inflammatory mediators that can further aggravate the retinal injury. Microglial activation as a harbinger of a variety of retinal diseases is well documented by many studies. In addition, a change in the microglial phenotype which may be associated with aging, may predispose the retina to age-related diseases. In light of the above, the focus of this review is to highlight the role played by microglia in the healthy and diseased retina, based on findings of our own work and from that of others.
Collapse
Affiliation(s)
- Gurugirijha Rathnasamy
- Department of Anatomy, Yong Loo Lin School of Medicine, Blk MD10, 4 Medical Drive, National University of Singapore, 117594, Singapore; Department of Ophthalmology and Visual Sciences, School of Medicine and Public Health, University of Wisconsin, Madison, WI, 53706, United States
| | - Wallace S Foulds
- Singapore Eye Research Institute Level 6, The Academia, Discovery Tower, 20 College Road, 169856, Singapore; University of Glasgow, Glasgow, Scotland, G12 8QQ, United Kingdom
| | - Eng-Ang Ling
- Department of Anatomy, Yong Loo Lin School of Medicine, Blk MD10, 4 Medical Drive, National University of Singapore, 117594, Singapore
| | - Charanjit Kaur
- Department of Anatomy, Yong Loo Lin School of Medicine, Blk MD10, 4 Medical Drive, National University of Singapore, 117594, Singapore.
| |
Collapse
|
9
|
Curcio CA, Zanzottera EC, Ach T, Balaratnasingam C, Freund KB. Activated Retinal Pigment Epithelium, an Optical Coherence Tomography Biomarker for Progression in Age-Related Macular Degeneration. Invest Ophthalmol Vis Sci 2017; 58:BIO211-BIO226. [PMID: 28785769 PMCID: PMC5557213 DOI: 10.1167/iovs.17-21872] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Purpose To summarize and contextualize recent histology and clinical imaging publications on retinal pigment epithelium (RPE) fate in advanced age-related macular degeneration (AMD); to support RPE activation and migration as important precursors to atrophy, manifest as intraretinal hyperreflective foci in spectral-domain optical coherence tomography (SDOCT). Methods The Project MACULA online resource for AMD histopathology was surveyed systematically to form a catalog of 15 phenotypes of RPE and RPE-derived cells and layer thicknesses in advanced disease. Phenotypes were also sought in correlations with clinical longitudinal eye-tracked SDOCT and with ex vivo imaging–histopathology correlations in geographic atrophy (GA) and pigment epithelium detachments (PED). Results The morphology catalog suggested two main pathways of RPE fate: basolateral shedding of intracellular organelles (apparent apoptosis in situ) and activation with anterior migration. Acquired vitelliform lesions may represent a third pathway. Migrated cells are packed with RPE organelles and confirmed as hyperreflective on SDOCT. RPE layer thickening due to cellular dysmorphia and thick basal laminar deposit is observed near the border of GA. Drusenoid PED show a life cycle of slow growth and rapid collapse preceded by RPE layer disruption and anterior migration. Conclusions RPE activation and migration comprise an important precursor to atrophy that can be observed at the cellular level in vivo via validated SDOCT. Collapse of large drusen and drusenoid PED appears to occur when RPE death and migration prevent continued production of druse components. Data implicate excessive diffusion distance from choriocapillaris in RPE death as well as support a potential benefit in targeting drusen in GA.
Collapse
Affiliation(s)
- Christine A Curcio
- Department of Ophthalmology, University of Alabama School of Medicine, Birmingham, Alabama, United States
| | - Emma C Zanzottera
- Eye Clinic, Department of Clinical Science "Luigi Sacco," Sacco Hospital, University of Milan, Milan, Italy
| | - Thomas Ach
- University Hospital Würzburg, Department of Ophthalmology, Würzburg, Germany
| | - Chandrakumar Balaratnasingam
- Center for Ophthalmology and Visual Sciences, Lions Eye Institute, University of Western Australia, Perth, Australia.,Sir Charles Gairdner Hospital, Perth, Australia
| | - K Bailey Freund
- Department of Ophthalmology, University of Alabama School of Medicine, Birmingham, Alabama, United States.,Eye Clinic, Department of Clinical Science "Luigi Sacco," Sacco Hospital, University of Milan, Milan, Italy.,University Hospital Würzburg, Department of Ophthalmology, Würzburg, Germany.,Center for Ophthalmology and Visual Sciences, Lions Eye Institute, University of Western Australia, Perth, Australia.,Sir Charles Gairdner Hospital, Perth, Australia.,Vitreous Retina Macula Consultants of New York, New York, New York, United States.,LuEsther T. Mertz Retinal Research Center, Manhattan Eye, Ear, and Throat Institute, New York, New York, United States.,Department of Ophthalmology, New York University Langone School of Medicine, New York, New York, United States
| |
Collapse
|
10
|
Campbell GJ, Senior AM, Bell-Anderson KS. Metabolic Effects of High Glycaemic Index Diets: A Systematic Review and Meta-Analysis of Feeding Studies in Mice and Rats. Nutrients 2017; 9:E646. [PMID: 28640233 PMCID: PMC5537766 DOI: 10.3390/nu9070646] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Revised: 06/16/2017] [Accepted: 06/17/2017] [Indexed: 12/24/2022] Open
Abstract
Low glycaemic index (LGI) diets are often reported to benefit metabolic health, but the mechanism(s) responsible are not clear. This review aimed to systematically identify studies investigating metabolic effects of high glycaemic index (HGI) versus LGI diets in mice and rats. A meta-analysis was conducted to calculate an overall effect size, Hedge's standardised mean differences (hereafter d), for each trait, with moderator variables considered in subsequent meta-regressions. Across 30 articles, a HGI diet increased five of the seven traits examined: body weight (d = 0.55; 95% confidence interval: 0.31, 0.79), fat mass (d = 1.08; 0.67, 1.49), fasting circulating insulin levels (d = 0.40; 0.09, 0.71), and glucose (d = 0.80; 0.35, 1.25) and insulin (d = 1.14; 0.50, 1.77) area under the curve during a glucose tolerance test. However, there was substantial heterogeneity among the effects for all traits and the small number of studies enabled only limited investigation of possible confounding factors. HGI diets favour body weight gain, increased adiposity and detrimentally affect parameters of glucose homeostasis in mice and rats, but these effects may not be a direct result of GI per se; rather they may be due to variation in other dietary constituents, such as dietary fibre, a factor which is known to reduce the GI of food and promote health via GI-independent mechanisms.
Collapse
Affiliation(s)
- Grace J Campbell
- Charles Perkins Centre, School of Life and Environmental Sciences, University of Sydney, Sydney, NSW 2006, Australia.
| | - Alistair M Senior
- Charles Perkins Centre, School of Mathematics and Statistics, University of Sydney, Sydney, NSW 2006, Australia.
| | - Kim S Bell-Anderson
- Charles Perkins Centre, School of Life and Environmental Sciences, University of Sydney, Sydney, NSW 2006, Australia.
| |
Collapse
|
11
|
Involvement of a gut-retina axis in protection against dietary glycemia-induced age-related macular degeneration. Proc Natl Acad Sci U S A 2017; 114:E4472-E4481. [PMID: 28507131 DOI: 10.1073/pnas.1702302114] [Citation(s) in RCA: 169] [Impact Index Per Article: 24.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Age-related macular degeneration (AMD) is the major cause of blindness in developed nations. AMD is characterized by retinal pigmented epithelial (RPE) cell dysfunction and loss of photoreceptor cells. Epidemiologic studies indicate important contributions of dietary patterns to the risk for AMD, but the mechanisms relating diet to disease remain unclear. Here we investigate the effect on AMD of isocaloric diets that differ only in the type of dietary carbohydrate in a wild-type aged-mouse model. The consumption of a high-glycemia (HG) diet resulted in many AMD features (AMDf), including RPE hypopigmentation and atrophy, lipofuscin accumulation, and photoreceptor degeneration, whereas consumption of the lower-glycemia (LG) diet did not. Critically, switching from the HG to the LG diet late in life arrested or reversed AMDf. LG diets limited the accumulation of advanced glycation end products, long-chain polyunsaturated lipids, and their peroxidation end-products and increased C3-carnitine in retina, plasma, or urine. Untargeted metabolomics revealed microbial cometabolites, particularly serotonin, as protective against AMDf. Gut microbiota were responsive to diet, and we identified microbiota in the Clostridiales order as being associated with AMDf and the HG diet, whereas protection from AMDf was associated with the Bacteroidales order and the LG diet. Network analysis revealed a nexus of metabolites and microbiota that appear to act within a gut-retina axis to protect against diet- and age-induced AMDf. The findings indicate a functional interaction between dietary carbohydrates, the metabolome, including microbial cometabolites, and AMDf. Our studies suggest a simple dietary intervention that may be useful in patients to arrest AMD.
Collapse
|
12
|
Rowan S, Taylor A. Gene-Diet Interactions in Age-Related Macular Degeneration. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 854:95-101. [PMID: 26427399 DOI: 10.1007/978-3-319-17121-0_14] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
Age-related macular degeneration (AMD) is a prevalent blinding disease, accounting for roughly 50 % of blindness in developed nations. Very significant advances have been made in terms of discovering genetic susceptibilities to AMD as well as dietary risk factors. To date, nutritional supplementation is the only available treatment option for the dry form of the disease known to slow progression of AMD. Despite an excellent understanding of genes and nutrition in AMD, there is remarkably little known about gene-diet interactions that may identify efficacious approaches to treat individuals. This review will summarize our current understanding of gene-diet interactions in AMD with a focus on animal models and human epidemiological studies.
Collapse
Affiliation(s)
- Sheldon Rowan
- USDA-JM Human Nutrition Research Center on Aging (HNRCA), Tufts University, 02111, Boston, MA, USA. .,Department of Ophthalmology, Tufts University School of Medicine, 02111, Boston, MA, USA.
| | - Allen Taylor
- USDA-JM Human Nutrition Research Center on Aging (HNRCA), Tufts University, 02111, Boston, MA, USA. .,Department of Ophthalmology, Tufts University School of Medicine, 02111, Boston, MA, USA. .,Friedman School of Nutrition Science and Policy, Tufts University, 02111, Boston, MA, USA.
| |
Collapse
|
13
|
Kleinman ME, Ambati J. Complement Activation and Inhibition in Retinal Diseases. DEVELOPMENTS IN OPHTHALMOLOGY 2015; 55:46-56. [PMID: 26501209 DOI: 10.1159/000431141] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/09/2022]
Abstract
Within the past several decades, a brigade of dedicated researchers from around the world has provided essential insights into the critical niche of immune-mediated inflammation in the pathogenesis of age-related macular degeneration (AMD). Yet, the question has lingered as to whether disease-initiating events are more or less dependent on isolated immune-related responses, unimpeded inflammation, endogenous pathways of age-related cell senescence and oxidative stress, or any of the other numerous molecular derangements that have been identified in the natural history of AMD. There is now an abundant cache of data signifying immune system activation as an impetus in the pathogenesis of this devastating condition. Furthermore, recent rigorous investigations have revealed multiple inciting factors, including several important complement-activating components, thus creating a new array of disease-modulating targets for the research and development of molecular therapeutic interventions. While the precise in vivo effects of complement activation and inhibition in the progression and treatment of AMD remain to be determined, ongoing clinical trials of the first generation of complement-targeted therapeutics are hoped to yield critical data on the contribution of this pathway to the disease process.
Collapse
|
14
|
Whitcomb EA, Chiu CJ, Taylor A. Dietary glycemia as a determinant of health and longevity. Mol Aspects Med 2015; 46:14-20. [PMID: 26282832 DOI: 10.1016/j.mam.2015.08.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2015] [Accepted: 08/04/2015] [Indexed: 11/17/2022]
Abstract
The role of diet in extending lifespan and healthspan has been the subject of much research and debate. Our recent epidemiological and in vivo data suggest that carbohydrate quality can be a major determinant in prolonging eye health. Additionally, excessive carbohydrate intake can contribute to the exacerbation of many different diseases. The metabolic diversity of the tissues that are affected by excessive carbohydrate intake suggests that dietary carbohydrate quality may affect cellular homeostasis.
Collapse
Affiliation(s)
- Elizabeth A Whitcomb
- Laboratory for Nutrition and Vision Research, USDA-Human Nutrition Research Center on Aging at Tufts University, Boston, MA 02111, USA
| | - Chung-Jung Chiu
- Laboratory for Nutrition and Vision Research, USDA-Human Nutrition Research Center on Aging at Tufts University, Boston, MA 02111, USA
| | - Allen Taylor
- Laboratory for Nutrition and Vision Research, USDA-Human Nutrition Research Center on Aging at Tufts University, Boston, MA 02111, USA.
| |
Collapse
|
15
|
Wang JCC, Cao S, Wang A, To E, Law G, Gao J, Zhang D, Cui JZ, Matsubara JA. CFH Y402H polymorphism is associated with elevated vitreal GM-CSF and choroidal macrophages in the postmortem human eye. Mol Vis 2015; 21:264-72. [PMID: 25814824 PMCID: PMC4360164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2014] [Accepted: 03/11/2015] [Indexed: 10/29/2022] Open
Abstract
PURPOSE Age-related macular degeneration (AMD) is the leading cause of irreversible blindness in people 50 years of age or older in developed countries. The homozygous CC genotype in the complement factor H (CFH) Y402H single nucleotide polymorphism (SNP; rs1061170) is widely recognized as a risk factor for the development of AMD. In this study, we examined vitreal levels of granulocyte macrophage colony-stimulating factor (GM-CSF), a hematopoietic cytokine, and macrophages in the choroid of postmortem human eyes genotyped for the CFH Y402H SNP. METHODS Twenty-two pairs of postmortem, non-diseased, human donor eyes were obtained. The vitreous and retinal tissues of the left eyes were collected for GM-CSF level measurement and CFH Y402H genotyping, respectively. The right eyes were paraffin-embedded and sectioned for immunohistochemistry using a macrophage and microglia marker, CD68. Cell cultures of RPE cells were stimulated with complement C3a, C5a, 4-hydroxynonenal (HNE), or tumor necrosis factor alpha (TNF-α), and GM-CSF expression was measured with a suspension assay or quantitative PCR. RESULTS Eyes genotyped with the CC or the CT risk variant of the CFH Y402H SNP showed significantly increased levels of GM-CSF in the vitreous compared to eyes with the protective TT variant (mean ± standard error of mean, 607.54±85.83 pg/ml or 656.32±15.20 pg/ml versus 286.69±81.96 pg/ml, p<0.05). The choroid of eye tissues genotyped with the CC variant showed higher levels of CD68 immunoreactivity than the tissues genotyped with the TT variant (p<0.05). The GM-CSF levels detected in the supernatant of RPE cells in culture treated with HNE or TNF-α were significantly higher compared to the non-treated control (145.88±5.06 pg/ml and 149.32±3.76 pg/ml versus 123.27±4.05 pg/ml, p<0.05). Furthermore, the gene expression of GM-CSF detected in the lysate of RPE cells stimulated with complement C3a or C5a showed significantly increased fold changes compared to the non-treated control (C3a: 2.38±0.31 fold, p<0.05; C5a: 2.84±0.54 fold, p<0.01). CONCLUSIONS Our data showed a relationship between the CFH Y402H polymorphism and GM-CSF levels in the vitreous and accumulation of choroidal macrophages in the postmortem eye. These data suggest that the at-risk variant of the CFH gene may contribute to the dysregulation of proinflammatory cytokines locally in the eye.
Collapse
|