101
|
Shin ES, Sorenson CM, Sheibani N. Diabetes and retinal vascular dysfunction. J Ophthalmic Vis Res 2015; 9:362-73. [PMID: 25667739 PMCID: PMC4307665 DOI: 10.4103/2008-322x.143378] [Citation(s) in RCA: 90] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2013] [Accepted: 01/19/2014] [Indexed: 02/06/2023] Open
Abstract
Diabetes predominantly affects the microvascular circulation of the retina resulting in a range of structural changes unique to this tissue. These changes ultimately lead to altered permeability, hyperproliferation of endothelial cells and edema, and abnormal vascularization of the retina with resulting loss of vision. Enhanced production of inflammatory mediators and oxidative stress are primary insults with significant contribution to the pathogenesis of diabetic retinopathy (DR). We have determined the identity of the retinal vascular cells affected by hyperglycemia, and have delineated the cell autonomous impact of high glucose on function of these cells. We discuss some of the high glucose specific changes in retinal vascular cells and their contribution to retinal vascular dysfunction. This knowledge provides novel insight into the molecular and cellular defects contributing to the development and progression of diabetic retinopathy, and will aid in the development of innovative, as well as target specific therapeutic approaches for prevention and treatment of DR.
Collapse
Affiliation(s)
- Eui Seok Shin
- Department of Ophthalmology and Visual Sciences, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Christine M Sorenson
- Department of Pediatrics, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA ; McPherson Eye Research Institute, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Nader Sheibani
- Department of Ophthalmology and Visual Sciences, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA ; McPherson Eye Research Institute, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| |
Collapse
|
102
|
Liegl R, Langer J, Seidensticker F, Reznicek L, Haritoglou C, Ulbig MW, Neubauer AS, Kampik A, Kernt M. Comparative evaluation of combined navigated laser photocoagulation and intravitreal ranibizumab in the treatment of diabetic macular edema. PLoS One 2014; 9:e113981. [PMID: 25541960 PMCID: PMC4277267 DOI: 10.1371/journal.pone.0113981] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2014] [Accepted: 11/02/2014] [Indexed: 11/24/2022] Open
Abstract
Objective To evaluate if a standardized combination therapy regimen, utilizing 3 monthly ranibizumab injections followed by navigated laser photocoagulation, reduces the number of total ranibizumab injections required for treatment of diabetic macular edema (DME). Research Design and Methods A 12-month, prospective comparison of 66 patients with center-involving DME: 34 patients with combination therapy were compared to 32 patients treated with ranibizumab monotherapy. All patients initially received 3 monthly ranibizumab injections (loading phase) and additional injections pro re nata (PRN). Combination therapy patients additionally received navigated laser photocoagulation after the loading phase. Main outcome measures were mean number of injections after the loading phase and change in BCVA from baseline to month 12. Results Navigated laser combination therapy and ranibizumab monotherapy similarly improved mean BCVA letter score (+8.41 vs. +6.31 letters, p = 0.258). In the combination group significantly less injections were required after the 3 injection loading phase (0.88±1.23 vs. 3.88±2.32, p< = 0.001). By month 12, 84% of patients in the monotherapy group had required additional ranibizumab injections as compared to 35% in the combination group (p< = 0.001). Conclusions Navigated laser combination therapy demonstrated significant visual gains in most patients. Retreatment rate and number of injections were significantly lower compared to ranibizumab monotherapy and compared to the results of conventional laser combination therapy previously reported in pivotal anti-VEGF studies.
Collapse
Affiliation(s)
- Raffael Liegl
- Department of Ophthalmology, Ludwig-Maximilians-University, Munich, Germany
| | - Julian Langer
- Department of Ophthalmology, Ludwig-Maximilians-University, Munich, Germany
| | | | - Lukas Reznicek
- Department of Ophthalmology, Ludwig-Maximilians-University, Munich, Germany
| | | | - Michael W. Ulbig
- Department of Ophthalmology, Ludwig-Maximilians-University, Munich, Germany
| | | | - Anselm Kampik
- Department of Ophthalmology, Ludwig-Maximilians-University, Munich, Germany
| | - Marcus Kernt
- Department of Ophthalmology, Ludwig-Maximilians-University, Munich, Germany
- * E-mail:
| |
Collapse
|
103
|
Usuelli V, La Rocca E. Novel therapeutic approaches for diabetic nephropathy and retinopathy. Pharmacol Res 2014; 98:39-44. [PMID: 25447794 DOI: 10.1016/j.phrs.2014.10.003] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/03/2014] [Revised: 10/03/2014] [Accepted: 10/16/2014] [Indexed: 12/13/2022]
Abstract
Diabetes mellitus is a chronic disease that in the long-term increases the microvascular and macrovascular degenerative complications thus being responsible for a large part of death associated with diabetes. During the years, while preventive care for diabetic patients has improved, the increase in the prevalence of diabetes worldwide is continuous. The detrimental effects of diabetes mellitus result in microvascular diseases, which recognize hyperglycemia as major determinant. A significant number of potential therapeutic targets for the treatment of diabetic microvascular complications have been proposed, but the encouraging results obtained in preclinical studies, have largely failed in clinical trials. Currently, the most successful strategy to prevent microvascular complications of diabetes is the intensive treatment of hyperglycemia or the normalization of glycometabolic control achieved with pancreatic and islet transplantation. In this review, we focus on the novel therapeutic targets to prevent the development and progression of diabetic nephropathy and retinopathy microvascular complications.
Collapse
Affiliation(s)
- Vera Usuelli
- Division of Transplant Medicine, IRCCS Ospedale San Raffaele, Milan, Italy
| | - Ennio La Rocca
- Division of Transplant Medicine, IRCCS Ospedale San Raffaele, Milan, Italy.
| |
Collapse
|
104
|
Zhou KK, Benyajati S, Le Y, Cheng R, Zhang W, Ma JX. Interruption of Wnt signaling in Müller cells ameliorates ischemia-induced retinal neovascularization. PLoS One 2014; 9:e108454. [PMID: 25271989 PMCID: PMC4182699 DOI: 10.1371/journal.pone.0108454] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2014] [Accepted: 08/29/2014] [Indexed: 01/26/2023] Open
Abstract
Retinal Müller cells are major producers of inflammatory and angiogenic cytokines which contribute to diabetic retinopathy (DR). Over-activation of the Wnt/β-catenin pathway has been shown to play an important pathogenic role in DR. However, the roles of Müller cell-derived Wnt/β-catenin signaling in retinal neovascularization (NV) and DR remain undefined. In the present study, mice with conditional β-catenin knockout (KO) in Müller cells were generated and subjected to oxygen-induced retinopathy (OIR) and streptozotocin (STZ)-induced diabetes. Wnt signaling was evaluated by measuring levels of β-catenin and expression of its target genes using immunoblotting. Retinal vascular permeability was measured using Evans blue as a tracer. Retinal NV was visualized by angiography and quantified by counting pre-retinal nuclei. Retinal pericyte loss was evaluated using retinal trypsin digestion. Electroretinography was performed to examine visual function. No abnormalities were detected in the β-catenin KO mice under normal conditions. In OIR, retinal levels of β-catenin and VEGF were significantly lower in the β-catenin KO mice than in littermate controls. The KO mice also had decreased retinal NV and vascular leakage in the OIR model. In the STZ-induced diabetic model, disruption of β-catenin in Müller cells attenuated over-expression of inflammatory cytokines and ameliorated pericyte dropout in the retina. These findings suggest that Wnt signaling activation in Müller cells contributes to retinal NV, vascular leakage and inflammation and represents a potential therapeutic target for DR.
Collapse
Affiliation(s)
- Kelu Kevin Zhou
- Department of Physiology, Harold Hamm Diabetes Center, the University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States of America
| | - Siribhinya Benyajati
- Department of Physiology, Harold Hamm Diabetes Center, the University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States of America
| | - Yun Le
- Department of Medicine Endocrinology, Harold Hamm Diabetes Center, the University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States of America
| | - Rui Cheng
- Department of Physiology, Harold Hamm Diabetes Center, the University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States of America
| | - Wenbo Zhang
- Department of Ophthalmology and Visual Sciences, the University of Texas Medical Branch, Galveston, Texas, United States of America
| | - Jian-xing Ma
- Department of Physiology, Harold Hamm Diabetes Center, the University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States of America
- * E-mail:
| |
Collapse
|
105
|
Wang J, Lin J, Schlotterer A, Wu L, Fleming T, Busch S, Dietrich N, Hammes HP. CD74 indicates microglial activation in experimental diabetic retinopathy and exogenous methylglyoxal mimics the response in normoglycemic retina. Acta Diabetol 2014; 51:813-21. [PMID: 24974304 DOI: 10.1007/s00592-014-0616-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2014] [Accepted: 06/13/2014] [Indexed: 10/25/2022]
Abstract
Diabetes induces vasoregression, neurodegeneration and glial activation in the retina. Formation of advanced glycation endoproducts (AGEs) is increased in diabetes and contributes to the pathogenesis of diabetic retinopathy. CD74 is increased in activated microglia in a rat model developing both neurodegeneration and vasoregression. In this study, we aimed at investigating whether glucose and major AGE precursor methylglyoxal induce increased CD74 expression in the retina. Expression of CD74 in retinal microglia was analyzed in streptozotocin-diabetic rats by wholemount immunofluorescence. Nondiabetic mice were intravitreally injected with methylglyoxal. Expression of CD74 was studied by retinal wholemount immunofluorescence and quantitative real-time PCR, 48 h after the injection. CD74-positive cells were increased in diabetic 4-month retinas. These cells represented a subpopulation of CD11b-labeled activated microglia and were mainly located in the superficial vascular layer (13.7-fold increase compared to nondiabetic group). Methylglyoxal induced an 9.4-fold increase of CD74-positive cells in the superficial vascular layer and elevated gene expression of CD74 in the mouse retina 2.8-fold. In summary, we identified CD74 as a microglial activation marker in the diabetic retina. Exogenous methylglyoxal mimics the response in normoglycemic retina. This suggests that methylglyoxal is important in mediating microglial activation in the diabetic retina.
Collapse
Affiliation(s)
- Jing Wang
- 5th Medical Department, Medical Faculty Mannheim, University of Heidelberg, Theodor-Kutzer-Ufer 1-3, 68167, Mannheim, Germany
| | | | | | | | | | | | | | | |
Collapse
|
106
|
Hussein KA, Choksi K, Akeel S, Ahmad S, Megyerdi S, El-Sherbiny M, Nawaz M, Abu El-Asrar A, Al-Shabrawey M. Bone morphogenetic protein 2: a potential new player in the pathogenesis of diabetic retinopathy. Exp Eye Res 2014; 125:79-88. [PMID: 24910902 DOI: 10.1016/j.exer.2014.05.012] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2013] [Revised: 03/10/2014] [Accepted: 05/15/2014] [Indexed: 12/23/2022]
Abstract
Diabetic retinopathy (DR) is one of the most common complications of diabetes mellitus. Vision loss in DR principally occurs due to breakdown of the blood-retinal barrier (BRB), leading to macular edema, retinal detachment and inner retinal and vitreous hemorrhage. Several growth factors have been shown to play crucial role in the development of these vascular changes; however, the cellular and molecular mechanisms of DR are not yet fully revealed. In the current study we investigated the role of bone morphogenetic protein-2 (BMP2) in DR. We examined the changes in the protein levels of BMP2 in human vitreous and retina in addition to the mouse retina of streptozotocin-induced diabetes. To detect the source of BMP2 during diabetes, human retinal endothelial cells (hRECs) were subjected to high glucose (HG) for 5 days and levels of BMP2 protein were analyzed in conditioned media of these cells relative to control. We also evaluated the effect of BMP2 on the levels of VEGF in cultured rat Müller cells (rMC1). In addition, we tested the pro-inflammatory effects of BMP2 by examining its effect on leukocyte adhesion to cultured hRECs, and levels of adhesion molecules and cytokines production. Finally, the effect of different concentrations of BMP2 on permeability of confluent monolayer of hRECs was evaluated using FITC-Dextran flux permeability assay and by measuring Transcellular Electrical Resistance (TER) using Electric Cell-substrate Impedance Sensing (ECIS). Our results show, for the first time, the up-regulation of BMP2 in diabetic human and mouse retinas in addition to its detection in vitreous of patients with proliferative DR (72 ± 7 pg/ml). In vitro, hRECs showed upregulation of BMP2 in HG conditions suggesting that these cells are a potential source of BMP2 in diabetic conditions. Furthermore, BMP2 induced VEGF secretion by Müller cells in-vitro; and showed a dose response in increasing permeability of cultured hRECs. Meanwhile, BMP2 pro-inflammatory effects were recognized by its ability to induce leukocyte adhesion to the hRECs, intercellular adhesion molecule-1 (ICAM-1) and upregulation of interleukin-6 and 8 (IL-6 and IL-8). These results show that BMP2 could be a contributing growth factor to the development of microvascular dysfunction during DR via enhancing both pro-angiogenic and inflammatory pathways. Our findings suggest BMP2 as a potential therapeutic target to prevent/treat DR.
Collapse
Affiliation(s)
- Khaled A Hussein
- Department of Oral Biology/Anatomy College of Dental Medicine, Georgia Reagents University (Augusta) (GRU(A)), USA; Vision Discovery Institute, Medical College of Georgia, GRU(A), USA; Oral and Dental Research Division, Department of Surgery and Medicine, National Research Center, Egypt
| | - Karishma Choksi
- Department of Oral Biology/Anatomy College of Dental Medicine, Georgia Reagents University (Augusta) (GRU(A)), USA; Vision Discovery Institute, Medical College of Georgia, GRU(A), USA
| | - Sara Akeel
- Department of Oral Biology/Anatomy College of Dental Medicine, Georgia Reagents University (Augusta) (GRU(A)), USA
| | - Saif Ahmad
- Vision Discovery Institute, Medical College of Georgia, GRU(A), USA; Department of Biological Sciences, Rabigh College of Science and Arts, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Sylvia Megyerdi
- Department of Oral Biology/Anatomy College of Dental Medicine, Georgia Reagents University (Augusta) (GRU(A)), USA
| | - Mohamed El-Sherbiny
- Department of Oral Biology/Anatomy College of Dental Medicine, Georgia Reagents University (Augusta) (GRU(A)), USA; Vision Discovery Institute, Medical College of Georgia, GRU(A), USA; Department of Anatomy, Mansoura Faculty of Medicine, Mansoura, Egypt
| | - Mohamed Nawaz
- Department of Ophthalmology, King Saud University, Riyadh, Saudi Arabia
| | | | - Mohamed Al-Shabrawey
- Department of Oral Biology/Anatomy College of Dental Medicine, Georgia Reagents University (Augusta) (GRU(A)), USA; Vision Discovery Institute, Medical College of Georgia, GRU(A), USA; Department of Anatomy, Mansoura Faculty of Medicine, Mansoura, Egypt; Department of Ophthalmology, Medical College of Georgia, GRU(A), USA; Department of Cellular Biology and Anatomy, GRU(A), USA.
| |
Collapse
|
107
|
The effect of lithospermic acid, an antioxidant, on development of diabetic retinopathy in spontaneously obese diabetic rats. PLoS One 2014; 9:e98232. [PMID: 24905410 PMCID: PMC4048190 DOI: 10.1371/journal.pone.0098232] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2013] [Accepted: 04/30/2014] [Indexed: 01/22/2023] Open
Abstract
Background Lithospermic acid B (LAB), an active component isolated from Salvia miltiorrhiza radix, has been reported to have antioxidant effects. We examined the effects of LAB on the prevention of diabetic retinopathy in Otsuka Long-Evans Tokushima Fatty (OLETF) rats, an animal model of type 2 diabetes. Methods and Findings LAB (10 or 20 mg/kg) or normal saline were given orally once daily to 24-week-old male OLETF rats for 52 weeks. At the end of treatment, fundoscopic findings, vascular endothelial growth factor (VEGF) expression in the eyeball, VEGF levels in the ocular fluid, and any structural abnormalities in the retina were assessed. Glucose metabolism, serum levels of high-sensitivity C-reactive protein (hsCRP), monocyte chemotactic protein-1 (MCP1), and tumor necrosis factor-alpha (TNFα) and urinary 8-hydroxy-2′-deoxyguanosine (8-OHdG) levels were also measured. Treatment with LAB prevented vascular leakage and basement membrane thickening in retinal capillaries in a dose-dependent manner. Insulin resistance and glucose intolerance were significantly improved by LAB treatment. The levels of serum hsCRP, MCP1, TNFα, and urinary 8-OHdG were lower in the LAB-treated OLETF rats than in the controls. Conclusions Treatment with LAB had a preventive effect on the development of diabetic retinopathy in this animal model, probably because of its antioxidative effects and anti-inflammatory effects.
Collapse
|
108
|
Semeraro F, Cancarini A, Morescalchi F, Romano MR, dell'Omo R, Ruggeri G, Agnifili L, Costagliola C. Serum and intraocular concentrations of erythropoietin and vascular endothelial growth factor in patients with type 2 diabetes and proliferative retinopathy. DIABETES & METABOLISM 2014; 40:445-51. [PMID: 24878492 DOI: 10.1016/j.diabet.2014.04.005] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2013] [Revised: 04/16/2014] [Accepted: 04/19/2014] [Indexed: 12/18/2022]
Abstract
AIM This study compared systemic and intraocular concentrations of erythropoietin (EPO) and vascular endothelial growth factor (VEGF) in patients with type 2 diabetes (T2D) and proliferative diabetic retinopathy (PDR) with levels in patients without diabetes, and looked for possible correlations between the concentrations found and other variables analyzed. METHODS Concentrations of EPO and VEGF were measured in the aqueous and vitreous humours and serum of patients undergoing vitrectomy for PDR (33 patients) or for macular holes or puckers (20 control patients). EPO was assayed by radioimmunoassay, with a lower limit of detection (LOD) of 1.0 mIU/mL. VEGF was assayed using enzyme-linked immunosorbent assay (ELISA), with a lower LOD of 10.0 pg/mL. RESULTS EPO concentrations in serum did not differ significantly between the two groups, whereas EPO in vitreous and aqueous were higher in diabetic than in non-diabetic patients. VEGF in serum was lower in diabetic patients than in non-diabetics; conversely, VEGF concentrations in vitreous were significantly higher in diabetic patients. A direct correlation was found between vitreous and aqueous EPO concentrations, and between vitreous EPO and blood glucose concentrations. A significant, negative correlation between vitreous EPO concentration and age was also recorded. CONCLUSION High EPO concentrations in the vitreous of patients with PDR and its correlation with blood glucose suggest that EPO could play a role in the pathogenesis of PDR. All possible factors affecting serum and ocular concentrations of EPO and VEGF should be determined to identify compounds able to prevent and control this serious microvascular complication of diabetes.
Collapse
Affiliation(s)
- F Semeraro
- Department of Medical and Surgical Specialties, Radiological Sciences and Public Health, University of Brescia, P.le Spedali Civili 1, 25123 Brescia, Italy
| | - A Cancarini
- Department of Medical and Surgical Specialties, Radiological Sciences and Public Health, University of Brescia, P.le Spedali Civili 1, 25123 Brescia, Italy.
| | - F Morescalchi
- Department of Medical and Surgical Specialties, Radiological Sciences and Public Health, University of Brescia, P.le Spedali Civili 1, 25123 Brescia, Italy
| | - M R Romano
- Department of Medicine and Health Sciences, University of Molise, Campobasso, Italy
| | - R dell'Omo
- Department of Medicine and Health Sciences, University of Molise, Campobasso, Italy
| | - G Ruggeri
- Department of Laboratory Medicine, A.O. Spedali Civili, Brescia, Italy
| | - L Agnifili
- Department of Ophthalmology, University of Chieti-Pescara, Chieti, Italy
| | - C Costagliola
- Department of Medicine and Health Sciences, University of Molise, Campobasso, Italy
| |
Collapse
|
109
|
Chhetri J, Jacobson G, Gueven N. Zebrafish--on the move towards ophthalmological research. Eye (Lond) 2014; 28:367-80. [PMID: 24503724 PMCID: PMC3983641 DOI: 10.1038/eye.2014.19] [Citation(s) in RCA: 105] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2013] [Accepted: 01/15/2014] [Indexed: 12/15/2022] Open
Abstract
Millions of people are affected by visual impairment and blindness globally, and the prevalence of vision loss is likely to increase as we are living longer. However, many ocular diseases remain poorly controlled due to lack of proper understanding of the pathogenesis and the corresponding lack of effective therapies. Consequently, there is a major need for animal models that closely mirror the human eye pathology and at the same time allow higher-throughput drug screening approaches. In this context, zebrafish as an animal model organism not only address these needs but can in many respects reflect the human situation better than the current rodent models. Over the past decade, zebrafish have become an established model to study a variety of human diseases and are more recently becoming a valuable tool for the study of human ophthalmological disorders. Many human ocular diseases such as cataract, glaucoma, diabetic retinopathy, and age-related macular degeneration have already been modelled in zebrafish. In addition, zebrafish have become an attractive model for pre-clinical drug toxicity testing and are now increasingly used by scientists worldwide for the discovery of novel treatment approaches. This review presents the advantages and uses of zebrafish for ophthalmological research.
Collapse
Affiliation(s)
- J Chhetri
- School of Pharmacy, University of Tasmania, Hobart, TAS, Australia
| | - G Jacobson
- School of Pharmacy, University of Tasmania, Hobart, TAS, Australia
| | - N Gueven
- School of Pharmacy, University of Tasmania, Hobart, TAS, Australia
| |
Collapse
|
110
|
Feng Y, Wang Y, Yang Z, Wu L, Hoffmann S, Wieland T, Gretz N, Hammes HP. Chronic hyperglycemia inhibits vasoregression in a transgenic model of retinal degeneration. Acta Diabetol 2014; 51:211-8. [PMID: 23771613 DOI: 10.1007/s00592-013-0488-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/07/2013] [Accepted: 05/27/2013] [Indexed: 10/26/2022]
Abstract
Vasoregression characterizes diabetic retinopathy in animal models and in humans. We have recently demonstrated that vasoregression is earlier initiated in a rat model of ciliopathy-induced retinal neurodegeneration (TGR rat). The aim was to assess the balance between vasoregressive effects of chronic hyperglycemia and photoreceptor degeneration on adult vascular remodelling. The retinas were analyzed at 4 and 9 months after streptozotocin-induced diabetes. Neurodegeneration was determined by quantitation of cell numbers and retinal layer thickness. Vasoregression was assessed by quantitative retinal morphometry in retinal digest preparations. Retinal VEGF levels were measured by ELISA. Glial activation, expression and location of HSP27 and phosphorylated HSP27 were evaluated by immunofluorescence staining. Unexpectedly, the numbers of acellular capillaries were reduced at both time points and led to fewer intraretinal microvascular abnormalities in late stage diabetic TGR. Concomitantly, inner nuclear layers (INLs) in diabetic TGR rats were protected from cell loss at both time points. Consequently, glial activation was reduced, but VEGF level was increased in diabetic TGR retinas. Expressions of HSP27 were upregulated in glia cells in the preserved INL of diabetic TGR. Chronic hyperglycemia preserves the microvasculature in the retinal model of neurodegeneration. Cell preservation in the retinal INL was associated with protective gene regulation. Together, these data indicate that diabetes can induce vasoprotection, in which retinal glia can play a particular role.
Collapse
Affiliation(s)
- Y Feng
- 5th Medical Clinic, Faculty of Clinical Medicine, University of Heidelberg, Mannheim, Germany,
| | | | | | | | | | | | | | | |
Collapse
|
111
|
Ola MS. Effect of hyperglycemia on insulin receptor signaling in the cultured retinal Müller glial cells. Biochem Biophys Res Commun 2014; 444:264-9. [DOI: 10.1016/j.bbrc.2014.01.052] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2014] [Accepted: 01/15/2014] [Indexed: 12/16/2022]
|
112
|
Pirie FJ, Maharaj S, Esterhuizen TM, Paruk IM, Motala AA. Retinopathy in subjects with type 2 diabetes at a tertiary diabetes clinic in Durban, South Africa: Clinical, biochemical and genetic factors. JOURNAL OF CLINICAL AND TRANSLATIONAL ENDOCRINOLOGY 2013; 1:e9-e12. [PMID: 29235587 PMCID: PMC5685021 DOI: 10.1016/j.jcte.2013.12.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 09/19/2013] [Revised: 12/12/2013] [Accepted: 12/13/2013] [Indexed: 11/25/2022]
Abstract
Aim To determine the prevalence of clinical and laboratory variables and genetic polymorphisms in association with diabetic retinopathy (DR) in subjects with type 2 diabetes attending a tertiary referral diabetes clinic in Durban, South Africa. Methods Cross-sectional study on 292 Indian and African patients with type 2 diabetes (71.5% women). The presence of DR was determined by direct ophthalmoscopy. Clinical and laboratory data were collected and polymorphisms in the NOS3 (rs61722009, rs2070744, rs1799983) and VEGF (rs35569394, rs2010963) genes were determined. Results DR was present in 113 (39%) subjects. Those with DR were older (60.6 ± 9.6 vs. 55.4 ± 12.9 years, p = 0.005), had longer duration diabetes (18.5 ± 8.8 vs. 11.9 ± 9.2 years, p < 0.0001), higher HbA1c (9.2 ± 1.8 vs. 8.8 ± 1.7%, p = 0.049), serum creatinine (106.3 ± 90.2 vs. 75.2 ± 33.4 μmol/l), triglycerides (2.1 ± 1.2 vs. 1.9 ± 1.6 mmol/l, p = 0.042), proteinuria (72% vs. 28%, p = 0.001), and used more insulin (78% vs. 39% p = 0.0001), anti-hypertensive (95% vs. 80%, p = 0.0003) and lipid-lowering therapy (70% vs. 56%, p = 0.023). There was no association between DR and any of the NOS3 or VEGF gene polymorphisms studied, although there were ethnic differences. After adjustment, diabetes duration (OR 1.05, 95% CI 1.01–1.08), presence of proteinuria (OR 4.15, 95% CI 1.70–10.11) and use of insulin therapy (OR 3.38, 95% CI 1.60–7.12) were associated with DR. Conclusion Hyperglycemia, duration of diabetes and proteinuria are associated with DR in Indian and African patients in South Africa, whereas NOS3 and VEGF gene polymorphisms were not associated with DR.
Collapse
Affiliation(s)
- F J Pirie
- Department of Diabetes and Endocrinology, University of KwaZulu-Natal, Nelson R Mandela School of Medicine, 419 Umbilo Road, Congella, Durban 4001, South Africa
| | - S Maharaj
- Department of Diabetes and Endocrinology, University of KwaZulu-Natal, Nelson R Mandela School of Medicine, 419 Umbilo Road, Congella, Durban 4001, South Africa
| | - T M Esterhuizen
- Programme of Bio & Research Ethics and Medical Law, College of Health Sciences, University of KwaZulu-Natal, Durban, South Africa
| | - I M Paruk
- Department of Diabetes and Endocrinology, University of KwaZulu-Natal, Nelson R Mandela School of Medicine, 419 Umbilo Road, Congella, Durban 4001, South Africa
| | - A A Motala
- Department of Diabetes and Endocrinology, University of KwaZulu-Natal, Nelson R Mandela School of Medicine, 419 Umbilo Road, Congella, Durban 4001, South Africa
| |
Collapse
|
113
|
High cystatin C levels predict severe retinopathy in type 2 diabetes patients. Eur J Epidemiol 2013; 28:775-8. [DOI: 10.1007/s10654-013-9839-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2013] [Accepted: 07/24/2013] [Indexed: 11/28/2022]
|