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Peng X, Zhang T, Liu R, Jin X. Potential in exosome-based targeted nano-drugs and delivery vehicles for posterior ocular disease treatment: from barriers to therapeutic application. Mol Cell Biochem 2024; 479:1319-1333. [PMID: 37402019 DOI: 10.1007/s11010-023-04798-w] [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: 04/13/2023] [Accepted: 06/21/2023] [Indexed: 07/05/2023]
Abstract
Posterior ocular disease, a disease that accounts for 55% of all ocular diseases, can contribute to permanent vision loss if left without treatment. Due to the special structure of the eye, various obstacles make it difficult for drugs to reach lesions in the posterior ocular segment. Therefore, the development of highly permeable targeted drugs and delivery systems is particularly important. Exosomes are a class of extracellular vesicles at 30-150 nm, which are secreted by various cells, tissues, and body fluids. They carry various signaling molecules, thus endowing them with certain physiological functions. In this review, we describe the ocular barriers and the biogenesis, isolation, and engineering of exosomes, as exosomes not only have pharmacological effects but also are good nanocarriers with targeted properties. Moreover, their biocompatibility and immunogenicity are better than synthetic nanocarriers. Most importantly, they may have the ability to pass through the blood-eye barrier. Thus, they may be developed as both targeted nano-drugs and nano-delivery vehicles for the treatment of posterior ocular diseases. We focus on the current status and potential application of exosomes as targeted nano-drugs and nano-delivery vehicles in posterior ocular diseases.
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Affiliation(s)
- Xingru Peng
- State Key Laboratory of Component‑based Chinese Medicine, Haihe Laboratory of Modern Chinese Medicine, College of Pharmaceutical Engineering of Traditional Chinese Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin, 301617, China
| | - Tingting Zhang
- State Key Laboratory of Component‑based Chinese Medicine, Haihe Laboratory of Modern Chinese Medicine, College of Pharmaceutical Engineering of Traditional Chinese Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin, 301617, China
| | - Rui Liu
- State Key Laboratory of Component‑based Chinese Medicine, Haihe Laboratory of Modern Chinese Medicine, College of Pharmaceutical Engineering of Traditional Chinese Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin, 301617, China.
| | - Xin Jin
- Department of Health Services, Logistics University of People's Armed Police Force, Tianjin, Chenlin Road, Hedong District, Tianjin, 300162, China.
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Lee SJ, Noh SE, Jo DH, Cho CS, Park KS, Kim JH. IL-10-induced modulation of macrophage polarization suppresses outer-blood-retinal barrier disruption in the streptozotocin-induced early diabetic retinopathy mouse model. FASEB J 2024; 38:e23638. [PMID: 38713098 DOI: 10.1096/fj.202400053r] [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: 01/10/2024] [Revised: 03/26/2024] [Accepted: 04/18/2024] [Indexed: 05/08/2024]
Abstract
Diabetic retinopathy (DR) is associated with ocular inflammation leading to retinal barrier breakdown, vascular leakage, macular edema, and vision loss. DR is not only a microvascular disease but also involves retinal neurodegeneration, demonstrating that pathological changes associated with neuroinflammation precede microvascular injury in early DR. Macrophage activation plays a central role in neuroinflammation. During DR, the inflammatory response depends on the polarization of retinal macrophages, triggering pro-inflammatory (M1) or anti-inflammatory (M2) activity. This study aimed to determine the role of macrophages in vascular leakage through the tight junction complexes of retinal pigment epithelium, which is the outer blood-retinal barrier (BRB). Furthermore, we aimed to assess whether interleukin-10 (IL-10), a representative M2-inducer, can decrease inflammatory macrophages and alleviate outer-BRB disruption. We found that modulation of macrophage polarization affects the structural and functional integrity of ARPE-19 cells in a co-culture system under high-glucose conditions. Furthermore, we demonstrated that intravitreal IL-10 injection induces an increase in the ratio of anti-inflammatory macrophages and effectively suppresses outer-BRB disruption and vascular leakage in a mouse model of early-stage streptozotocin-induced diabetes. Our results suggest that modulation of macrophage polarization by IL-10 administration during early-stage DR has a promising protective effect against outer-BRB disruption and vascular leakage. This finding provides valuable insights for early intervention in DR.
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Affiliation(s)
- Seok Jae Lee
- Fight against Angiogenesis-Related Blindness (FARB) Laboratory, Clinical Research Institute, Seoul National University Hospital, Seoul, Republic of Korea
- Global Excellence Center for Gene & Cell Therapy (GEC-GCT), Seoul National University Hospital, Seoul, Republic of Korea
| | - Sung-Eun Noh
- Fight against Angiogenesis-Related Blindness (FARB) Laboratory, Clinical Research Institute, Seoul National University Hospital, Seoul, Republic of Korea
- Global Excellence Center for Gene & Cell Therapy (GEC-GCT), Seoul National University Hospital, Seoul, Republic of Korea
| | - Dong Hyun Jo
- Global Excellence Center for Gene & Cell Therapy (GEC-GCT), Seoul National University Hospital, Seoul, Republic of Korea
- Department of Anatomy & Cell Biology, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Chang Sik Cho
- Fight against Angiogenesis-Related Blindness (FARB) Laboratory, Clinical Research Institute, Seoul National University Hospital, Seoul, Republic of Korea
- Global Excellence Center for Gene & Cell Therapy (GEC-GCT), Seoul National University Hospital, Seoul, Republic of Korea
| | - Kyu-Sang Park
- Department of Physiology, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea
| | - Jeong Hun Kim
- Fight against Angiogenesis-Related Blindness (FARB) Laboratory, Clinical Research Institute, Seoul National University Hospital, Seoul, Republic of Korea
- Global Excellence Center for Gene & Cell Therapy (GEC-GCT), Seoul National University Hospital, Seoul, Republic of Korea
- Department of Biomedical Sciences & Ophthalmology, Seoul National University College of Medicine, Seoul, Republic of Korea
- Institute of Reproductive Medicine and Population, Seoul National University College of Medicine, Seoul, Republic of Korea
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3
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Lim RR, Mahaling B, Tan A, Mehta M, Kaur C, Hunziker W, Kim JE, Barathi VA, Ghosh A, Chaurasia SS. ITF2357 regulates NF-κB signaling pathway to protect barrier integrity in retinal pigment epithelial cells. FASEB J 2024; 38:e23512. [PMID: 38430220 PMCID: PMC11019659 DOI: 10.1096/fj.202301592r] [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: 08/04/2023] [Revised: 12/27/2023] [Accepted: 02/09/2024] [Indexed: 03/03/2024]
Abstract
The robust integrity of the retinal pigment epithelium (RPE), which contributes to the outer brain retina barrier (oBRB), is compromised in several retinal degenerative and vascular disorders, including diabetic macular edema (DME). This study evaluates the role of a new generation of histone deacetylase inhibitor (HDACi), ITF2357, in regulating outer blood-retinal barrier function and investigates the underlying mechanism of action in inhibiting TNFα-induced damage to RPE integrity. Using the immortalized RPE cell line (ARPE-19), ITF2357 was found to be non-toxic between 50 nM and 5 μM concentrations. When applied as a pre-treatment in conjunction with an inflammatory cytokine, TNFα, the HDACi was safe and effective in preventing epithelial permeability by fortifying tight junction (ZO-1, -2, -3, occludin, claudin-1, -2, -3, -5, -19) and adherens junction (E-cadherin, Nectin-1) protein expression post-TNFα stress. Mechanistically, ITF2357 depicted a late action at 24 h via attenuating IKK, IκBα, and p65 phosphorylation and ameliorated the expression of IL-1β, IL-6, and MCP-1. Also, ITF2357 delayed IκBα synthesis and turnover. The use of Bay 11-7082 and MG132 further uncovered a possible role for ITF2357 in non-canonical NF-κB activation. Overall, this study revealed the protection effects of ITF2357 by regulating the turnover of tight and adherens junction proteins and modulating NF-κB signaling pathway in the presence of an inflammatory stressor, making it a potential therapeutic application for retinal vascular diseases such as DME with compromised outer blood-retinal barrier.
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Affiliation(s)
- Rayne R. Lim
- Ocular Immunology and Angiogenesis Lab, Department of Ophthalmology and Visual Sciences, Medical College of Wisconsin Eye Institute, Milwaukee, WI, USA
| | - Binapani Mahaling
- Ocular Immunology and Angiogenesis Lab, Department of Ophthalmology and Visual Sciences, Medical College of Wisconsin Eye Institute, Milwaukee, WI, USA
| | - Alison Tan
- Singapore Eye Research Institute, Singapore, Singapore
| | - Milan Mehta
- Singapore Eye Research Institute, Singapore, Singapore
| | - Charanjit Kaur
- Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Walter Hunziker
- Institute of Molecular and Cellular Biology, A*STAR Agency, Singapore, Singapore
- Yong Loo Lin School of Medicine, National University of Singapore, Singapore
- Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Judy E. Kim
- Ocular Immunology and Angiogenesis Lab, Department of Ophthalmology and Visual Sciences, Medical College of Wisconsin Eye Institute, Milwaukee, WI, USA
| | - Veluchamy A. Barathi
- Singapore Eye Research Institute, Singapore, Singapore
- Centre for Vision Research, Duke NUS Medical School, 8 College Road, Singapore
| | | | - Shyam S. Chaurasia
- Ocular Immunology and Angiogenesis Lab, Department of Ophthalmology and Visual Sciences, Medical College of Wisconsin Eye Institute, Milwaukee, WI, USA
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, WI, USA
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Rodriguez D, Church KA, Smith CT, Vanegas D, Cardona SM, Muzzio IA, Nash KR, Cardona AE. Therapeutic Delivery of Soluble Fractalkine Ameliorates Vascular Dysfunction in the Diabetic Retina. Int J Mol Sci 2024; 25:1727. [PMID: 38339005 PMCID: PMC10855319 DOI: 10.3390/ijms25031727] [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: 12/14/2023] [Revised: 01/20/2024] [Accepted: 01/27/2024] [Indexed: 02/12/2024] Open
Abstract
Diabetic retinopathy (DR)-associated vision loss is a devastating disease affecting the working-age population. Retinal pathology is due to leakage of serum components into retinal tissues, activation of resident phagocytes (microglia), and vascular and neuronal damage. While short-term interventions are available, they do not revert visual function or halt disease progression. The impact of microglial inflammatory responses on the neurovascular unit remains unknown. In this study, we characterized microglia-vascular interactions in an experimental model of DR. Early diabetes presents activated retinal microglia, vascular permeability, and vascular abnormalities coupled with vascular tortuosity and diminished astrocyte and endothelial cell-associated tight-junction (TJ) and gap-junction (GJ) proteins. Microglia exclusively bind to the neuronal-derived chemokine fractalkine (FKN) via the CX3CR1 receptor to ameliorate microglial activation. Using neuron-specific recombinant adeno-associated viruses (rAAVs), we therapeutically overexpressed soluble (sFKN) or membrane-bound (mFKN) FKN using intra-vitreal delivery at the onset of diabetes. This study highlights the neuroprotective role of rAAV-sFKN, reducing microglial activation, vascular tortuosity, fibrin(ogen) deposition, and astrogliosis and supporting the maintenance of the GJ connexin-43 (Cx43) and TJ zonula occludens-1 (ZO-1) molecules. The results also show that microglia-vascular interactions influence the vascular width upon administration of rAAV-sFKN and rAAV-mFKN. Administration of rAAV-sFKN improved visual function without affecting peripheral immune responses. These findings suggest that overexpression of rAAV-sFKN can mitigate vascular abnormalities by promoting glia-neural signaling. sFKN gene therapy is a promising translational approach to reverse vision loss driven by vascular dysfunction.
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Affiliation(s)
- Derek Rodriguez
- Department of Molecular Microbiology and Immunology, The University of Texas at San Antonio, San Antonio, TX 78249, USA; (D.R.); (K.A.C.); (C.T.S.); (D.V.); (S.M.C.)
| | - Kaira A. Church
- Department of Molecular Microbiology and Immunology, The University of Texas at San Antonio, San Antonio, TX 78249, USA; (D.R.); (K.A.C.); (C.T.S.); (D.V.); (S.M.C.)
| | - Chelsea T. Smith
- Department of Molecular Microbiology and Immunology, The University of Texas at San Antonio, San Antonio, TX 78249, USA; (D.R.); (K.A.C.); (C.T.S.); (D.V.); (S.M.C.)
| | - Difernando Vanegas
- Department of Molecular Microbiology and Immunology, The University of Texas at San Antonio, San Antonio, TX 78249, USA; (D.R.); (K.A.C.); (C.T.S.); (D.V.); (S.M.C.)
| | - Sandra M. Cardona
- Department of Molecular Microbiology and Immunology, The University of Texas at San Antonio, San Antonio, TX 78249, USA; (D.R.); (K.A.C.); (C.T.S.); (D.V.); (S.M.C.)
| | - Isabel A. Muzzio
- Department of Psychological and Brain Sciences, University of Iowa, Iowa City, IA 52242, USA;
| | - Kevin R. Nash
- Department of Molecular Pharmacology and Physiology, University of South Florida, Tampa, FL 33612, USA;
| | - Astrid E. Cardona
- Department of Molecular Microbiology and Immunology, The University of Texas at San Antonio, San Antonio, TX 78249, USA; (D.R.); (K.A.C.); (C.T.S.); (D.V.); (S.M.C.)
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Dmitriev AV, Dmitriev AA, Linsenmeier RA. Diabetes-Induced Changes of the Rat ERG in Relation to Hyperglycemia and Acidosis. Curr Eye Res 2024; 49:53-61. [PMID: 37756520 PMCID: PMC10872866 DOI: 10.1080/02713683.2023.2264544] [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: 06/06/2023] [Accepted: 09/22/2023] [Indexed: 09/29/2023]
Abstract
PURPOSE To understand the mechanism of changes in the c-wave of the electroretinogram (ERG) in diabetic rats, and to explore how glucose manipulations affect the c-wave. METHODS Vitreal ERGs were recorded in control and diabetic Long-Evans rats, 3-60 weeks after IP vehicle or streptozotocin. A few experiments were performed on Brown Norway rats. Voltage responses to current pulses were used to measure the transepithelial resistance of the retinal pigment epithelium (RPE). RESULTS During development of diabetes the b-wave amplitude progressively decreased to about half of the initial amplitude after a year. In contrast, the c-wave was strongly affected from the very beginning (3 weeks) of diabetes. In control rats, the c-wave was cornea-positive at lower illuminations but was cornea-negative at higher (photopic) illumination. In diabetics, the whole amplitude-intensity curve was shifted toward negativity. The magnitude of this shift was markedly affected by acute glucose manipulations in diabetics but not in controls. Increased blood glucose made the c-wave more negative, and decreased blood glucose with insulin had the opposite effect. Experimentally induced acidification of the retina had a small effect that was different from diabetes, shifting the c-wave toward positivity, slightly in controls and more noticeably in diabetics. One reason for the significant negativity of the diabetic ERG was a decrease of the cornea-positive response of the RPE due to a decrease of the transepithelial resistance. CONCLUSIONS The ERG c-wave is more negative in diabetics than in control animals, and is far more sensitive to changes in blood glucose. The increased negativity is largely if not entirely due to changes in the transepithelial resistance of the RPE, an electrical analog of the breakdown of the blood-retinal barrier observed in other studies. The sensitivity of the c-wave to glucose in diabetics may also be due to changes in transepithelial resistance.
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Affiliation(s)
| | | | - Robert A Linsenmeier
- Department of Biomedical Engineering, Evanston and Chicago, IL
- Department of Neurobiology, Evanston and Chicago, IL
- Department of Ophthalmology Northwestern University, Evanston and Chicago, IL
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6
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Wang T, Wang X, Fu T, Ma Y, Wang Q, Zhang S, Zhang X, Zhou H, Chang X, Tong Y. Roles of mitochondrial dynamics and mitophagy in diabetic myocardial microvascular injury. Cell Stress Chaperones 2023; 28:675-688. [PMID: 37755621 PMCID: PMC10746668 DOI: 10.1007/s12192-023-01384-3] [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: 07/28/2023] [Revised: 09/04/2023] [Accepted: 09/11/2023] [Indexed: 09/28/2023] Open
Abstract
Myocardial microvessels are composed of a monolayer of endothelial cells, which play a crucial role in maintaining vascular barrier function, luminal latency, vascular tone, and myocardial perfusion. Endothelial dysfunction is a key factor in the development of cardiac microvascular injury and diabetic cardiomyopathy. In addition to their role in glucose oxidation and energy metabolism, mitochondria also participate in non-metabolic processes such as apoptosis, intracellular ion handling, and redox balancing. Mitochondrial dynamics and mitophagy are responsible for regulating the quality and quantity of mitochondria in response to hyperglycemia. However, these endogenous homeostatic mechanisms can both preserve and/or disrupt non-metabolic mitochondrial functions during diabetic endothelial damage and cardiac microvascular injury. This review provides an overview of the molecular features and regulatory mechanisms of mitochondrial dynamics and mitophagy. Furthermore, we summarize findings from various investigations that suggest abnormal mitochondrial dynamics and defective mitophagy contribute to the development of diabetic endothelial dysfunction and myocardial microvascular injury. Finally, we discuss different therapeutic strategies aimed at improving endothelial homeostasis and cardiac microvascular function through the enhancement of mitochondrial dynamics and mitophagy.
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Affiliation(s)
- Tong Wang
- Heilongjiang Academy of Chinese Medicine, Harbin, 150000, China
| | - Xinwei Wang
- Heilongjiang Academy of Chinese Medicine, Harbin, 150000, China
| | - Tong Fu
- Brandeis University, Waltham, MA, 02453, USA
| | - Yanchun Ma
- Heilongjiang Academy of Chinese Medicine, Harbin, 150000, China
| | - Qi Wang
- First Affiliated Hospital, Heilongjiang University of Chinese Medicine, Harbin, 150040, China
| | - Shuxiang Zhang
- Heilongjiang Academy of Chinese Medicine, Harbin, 150000, China
| | - Xiao Zhang
- Senior Department of Cardiology, The Sixth Medical Center of People's Liberation Army General Hospital, Beijing, 100048, China
| | - Hao Zhou
- Senior Department of Cardiology, The Sixth Medical Center of People's Liberation Army General Hospital, Beijing, 100048, China
| | - Xing Chang
- Cardiovascular Department, Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, 100053, China.
| | - Ying Tong
- First Affiliated Hospital, Heilongjiang University of Chinese Medicine, Harbin, 150040, China.
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Loukovaara S, Korhonen A, Niskanen L, Haukka J. Development of diabetic macular oedema shows associations with systemic medication - An epidemiological study. Acta Ophthalmol 2023. [PMID: 37789702 DOI: 10.1111/aos.15778] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Revised: 08/15/2023] [Accepted: 09/18/2023] [Indexed: 10/05/2023]
Abstract
PURPOSE To identify associations between systemic drugs and the incidence of diabetic macular oedema (DME). Of interest was to find beneficial and/or deleterious associations of used drugs. METHODS A historic cohort design based on administrative data. Study population consisted of 150 353 individuals with diabetes. Endpoint event was the development of DME (ICD-10 H36.01), censoring events were death or study end December 2017. The follow-up started between 1997 and 2010. The systemic medication consisted of 95 substances. We constructed a nested case-control study design comparing 2630 cases with DME to 13 144 age- and sex-matched controls without DME. Results are reported as odds ratios (ORs) with 95% confidence intervals (CIs) based on conditional logistic regression models. RESULTS Incidence rate for DME was 1.80 per 1000 person-years (95% CI 1.73-1.87). In all, we observed a lower incidence rate of DME in females (IRR 0.57; 95% CI 0.52-0.62) compared to males. Exposure to hormone replacement therapy estradiol (OR 0.42; 0.25-0.68), temazepam (0.23; 0.08-0.62) and allopurinol (0.61; 0.43-0.86) were associated with lower risk of DME, while use of insulin or insulin analogue (3.30; 2.99-3.64), sulfonylureas (1.21; 1.05-1.40), diuretic furosemide (1.90; 1.61-2.24), calcium channel blocker amlodipine (1.53; 1.34-1.75), ACE inhibitors ramipril (1.66; 1.46-1.89) and enalapril (1.38; 1.16-1.64) were associated with an increased risk of DME. CONCLUSIONS Large-scale studies examining the incidence of DME are lacking. Our findings suggest that associations of systemic medications with the incidence of DME may shed light on the pathogenesis of complex DME, encouraging further studies.
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Affiliation(s)
- Sirpa Loukovaara
- Individualized Drug Therapy Research Program, University of Helsinki, Helsinki, Finland
- Unit of Vitreoretinal Surgery, Department of Ophthalmology, Helsinki University Hospital, Helsinki, Finland
| | - Ani Korhonen
- Individualized Drug Therapy Research Program, University of Helsinki, Helsinki, Finland
| | - Leo Niskanen
- Päijät-Häme Central Hospital, Lahti and Eira Hospital, Helsinki Finland and University of Eastern Finland, Kuopio, Finland
| | - Jari Haukka
- Department of Public Health, University of Helsinki, Helsinki, Finland
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Hernandez BJ, Skiba NP, Plössl K, Strain M, Liu Y, Grigsby D, Kelly U, Cady MA, Manocha V, Maminishkis A, Watkins T, Miller SS, Ashley‐Koch A, Stamer WD, Weber BHF, Bowes Rickman C, Klingeborn M. Polarized Desmosome and Hemidesmosome Shedding via Small Extracellular Vesicles is an Early Indicator of Outer Blood-Retina Barrier Dysfunction. JOURNAL OF EXTRACELLULAR BIOLOGY 2023; 2:e116. [PMID: 38108061 PMCID: PMC10720597 DOI: 10.1002/jex2.116] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Revised: 08/30/2023] [Accepted: 09/11/2023] [Indexed: 12/19/2023]
Abstract
The retinal pigmented epithelium (RPE) constitutes the outer blood-retinal barrier, enables photoreceptor function of the eye, and is constantly exposed to oxidative stress. As such, dysfunction of the RPE underlies pathology leading to development of age-related macular degeneration (AMD), the leading cause of vision loss among the elderly in industrialized nations. A major responsibility of the RPE is to process photoreceptor outer segments, which relies on the proper functioning of its endocytic pathways and endosomal trafficking. Exosomes and other extracellular vesicles (EVs) from RPE are an essential part of these pathways and may be early indicators of cellular stress. To test the role of small EVs (sEVs) including exosomes, that may underlie the early stages of AMD, we used a polarized primary RPE cell culture model under chronic subtoxic oxidative stress. Unbiased proteomic analyses of highly purified basolateral sEVs from oxidatively stressed RPE cultures revealed changes in proteins involved in epithelial barrier integrity. There were also significant changes in proteins accumulating in the basal-side sub-RPE extracellular matrix during oxidative stress, that could be prevented with an inhibitor of sEV release. Thus, chronic subtoxic oxidative stress in primary RPE cultures induces changes in sEV content, including basal-side specific desmosome and hemidesmosome shedding via sEVs. These findings provide novel biomarkers of early cellular dysfunction and opportunity for therapeutic intervention in age-related retinal diseases (e.g., AMD).
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Affiliation(s)
- Belinda J. Hernandez
- Department of Ophthalmology, Duke Eye CenterDuke UniversityDurhamNorth CarolinaUSA
| | - Nikolai P. Skiba
- Department of Ophthalmology, Duke Eye CenterDuke UniversityDurhamNorth CarolinaUSA
| | - Karolina Plössl
- Institute of Human GeneticsUniversity of RegensburgRegensburgGermany
| | - Madison Strain
- Duke Molecular Physiology Institute, Department of MedicineDuke UniversityDurhamNorth CarolinaUSA
| | - Yutao Liu
- Department of Cellular Biology and AnatomyAugusta UniversityAugustaGeorgiaUSA
| | - Daniel Grigsby
- Department of Ophthalmology, Duke Eye CenterDuke UniversityDurhamNorth CarolinaUSA
| | - Una Kelly
- Department of Ophthalmology, Duke Eye CenterDuke UniversityDurhamNorth CarolinaUSA
| | - Martha A. Cady
- Department of Ophthalmology, Duke Eye CenterDuke UniversityDurhamNorth CarolinaUSA
| | - Vikram Manocha
- Department of Ophthalmology, Duke Eye CenterDuke UniversityDurhamNorth CarolinaUSA
| | - Arvydas Maminishkis
- Ophthalmic Genetics and Visual Function Branch, Section on Epithelial and Retinal Physiology and DiseaseNational Eye Institute, National Institutes of HealthBethesdaMarylandUSA
| | - TeddiJo Watkins
- Department of Ophthalmology, Duke Eye CenterDuke UniversityDurhamNorth CarolinaUSA
- Office of Animal Welfare Assurance, Duke Animal Care and Use ProgramDuke UniversityDurhamNorth CarolinaUSA
| | - Sheldon S. Miller
- Ophthalmic Genetics and Visual Function Branch, Section on Epithelial and Retinal Physiology and DiseaseNational Eye Institute, National Institutes of HealthBethesdaMarylandUSA
| | - Allison Ashley‐Koch
- Duke Molecular Physiology Institute, Department of MedicineDuke UniversityDurhamNorth CarolinaUSA
| | - W. Daniel Stamer
- Department of Ophthalmology, Duke Eye CenterDuke UniversityDurhamNorth CarolinaUSA
- Department of Biomedical EngineeringDuke UniversityDurhamNorth CarolinaUSA
| | - Bernhard H. F. Weber
- Institute of Human GeneticsUniversity of RegensburgRegensburgGermany
- Institute of Clinical Human GeneticsUniversity Hospital RegensburgRegensburgGermany
| | - Catherine Bowes Rickman
- Department of Ophthalmology, Duke Eye CenterDuke UniversityDurhamNorth CarolinaUSA
- Department of Cell BiologyDuke UniversityDurhamNorth CarolinaUSA
| | - Mikael Klingeborn
- Department of Ophthalmology, Duke Eye CenterDuke UniversityDurhamNorth CarolinaUSA
- McLaughlin Research InstituteGreat FallsMontanaUSA
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9
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Nam U, Lee S, Jeon JS. Generation of a 3D Outer Blood-Retinal Barrier with Advanced Choriocapillaris and Its Application in Diabetic Retinopathy in a Microphysiological System. ACS Biomater Sci Eng 2023; 9:4929-4939. [PMID: 37494673 DOI: 10.1021/acsbiomaterials.3c00326] [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] [Indexed: 07/28/2023]
Abstract
The outer blood-retinal barrier (oBRB) provides an optimal environment for the function of the photoreceptor by regulating the exchange of molecules between subretinal space and the choriocapillaris, and its dysfunction could impair the photoreceptor's function and vision. The existing in vitro models have limitations in reproducing the barrier function or physiological characteristics of oBRB and choriocapillaris. Here, we engineered a microphysiological system-based oBRB-choriocapillaris model that simultaneously incorporates the desired physiological characteristics and is simple to fabricate. First, we generated microvascular networks to mimic choriocapillaris and investigated the role of fibroblasts in vasculogenesis. By adding retinal pigment epithelial cells to one side of blood vessels formed with endothelial cells and fibroblasts and optimizing their culture medium conditions, we established an oBRB-choriocapillaris model. To verify the physiological similarity of our oBRB-choriocapillaris model, we identified the polarization and expression of the tight junction of the retinal pigment epithelium, Bruch's membrane, and the fenestral diaphragm of choriocapillaris. Finally, we tried to recapitulate the diabetes mellitus environment in our model with hyperglycemia and diabetes-related cytokines. This induced a decrease in tight junction integrity, loss of barrier function, and shrinkage of blood vessels, similar to the in vivo pathological changes observed in the oBRB and choriocapillaris. The oBRB-choriocapillaris model developed using a microphysiological system is expected to offer a valuable in vitro platform for retinal and choroidal vascular diseases in preclinical applications.
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Affiliation(s)
- Ungsig Nam
- Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology, Daejeon 34141, Republic of Korea
| | - Seokhun Lee
- Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology, Daejeon 34141, Republic of Korea
| | - Jessie S Jeon
- Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology, Daejeon 34141, Republic of Korea
- KAIST Institute for Health Science and Technology, Korea Advanced Institute of Science and Technology, Daejeon 34141, Republic of Korea
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10
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Bardak H, Uğuz AC, Bardak Y, Rocha-Pimienta J, Delgado-Adámez J, Espino J. Selenium Protects ARPE-19 and ACBRI 181 Cells against High Glucose-Induced Oxidative Stress. Molecules 2023; 28:5961. [PMID: 37630213 PMCID: PMC10459791 DOI: 10.3390/molecules28165961] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Revised: 08/02/2023] [Accepted: 08/05/2023] [Indexed: 08/27/2023] Open
Abstract
Diabetic retinopathy (DR), a complication of diabetes mellitus (DM), can cause severe visual loss. The retinal pigment epithelium (RPE) plays a crucial role in retinal physiology but is vulnerable to oxidative damage. We investigated the protective effects of selenium (Se) on retinal pigment epithelium (ARPE-19) and primary human retinal microvascular endothelial (ACBRI 181) cells against high glucose (HG)-induced oxidative stress and apoptotic cascade. To achieve this objective, we utilized varying concentrations of D-glucose (ranging from 5 to 80 mM) to induce the HG model. HG-induced oxidative stress in ARPE-19 and ACBRI 181 cells and the apoptotic cascade were evaluated by determining Ca2+ overload, mitochondrial membrane depolarization, caspase-3/-9 activation, intracellular reactive oxygen species (ROS), lipid peroxidation (LP), glutathione (GSH), glutathione peroxidase (GSH-Px), vascular endothelial growth factor (VEGF) and apoptosis levels. A cell viability assay utilizing MTT was conducted to ascertain the optimal concentration of Se to be employed. The quantification of MTT, ROS, VEGF levels, and caspase-3 and -9 activation was accomplished using a plate reader. To quantitatively assess LP and GSH levels, GSH-Px activities were utilized by spectrophotometer and apoptosis, mitochondrial membrane depolarization, and the release of Ca2+ from intracellular stores were evaluated by spectrofluorometer. Our investigation revealed a significant augmentation in oxidative stress induced by HG, leading to cellular damage through modulation of mitochondrial membrane potential, ROS levels, and intracellular Ca2+ release. Incubation with Se resulted in a notable reduction in ROS production induced by HG, as well as a reduction in apoptosis and the activation of caspase-3 and -9. Additionally, Se incubation led to decreased levels of VEGF and LP while concurrently increasing levels of GSH and GSH-Px. The findings from this study strongly suggest that Se exerts a protective effect on ARPE-19 and ACBRI 181 cells against HG-induced oxidative stress and apoptosis. This protective mechanism is partially mediated through the intracellular Ca2+ signaling pathway.
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Affiliation(s)
- Handan Bardak
- Department of Ophthalmology, Asya Hospital, 34100 Istanbul, Turkey;
| | - Abdülhadi Cihangir Uğuz
- Department of Biophysics, Faculty of Medicine, Karamanoğlu Mehmetbey University, 70100 Karaman, Turkey
| | | | - Javier Rocha-Pimienta
- Technological Agri-Food Institute (CICYTEX-INTAEX), Junta of Extremadura, Avda. Adolfo Suárez s/n, 06007 Badajoz, Spain; (J.R.-P.); (J.D.-A.)
| | - Jonathan Delgado-Adámez
- Technological Agri-Food Institute (CICYTEX-INTAEX), Junta of Extremadura, Avda. Adolfo Suárez s/n, 06007 Badajoz, Spain; (J.R.-P.); (J.D.-A.)
| | - Javier Espino
- Department of Physiology, Faculty of Science, University of Extremadura, Avda. de Elvas, s/n, 06006 Badajoz, Spain
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Daley R, Maddipatla V, Ghosh S, Chowdhury O, Hose S, Zigler JS, Sinha D, Liu H. Aberrant Akt2 signaling in the RPE may contribute to retinal fibrosis process in diabetic retinopathy. Cell Death Discov 2023; 9:243. [PMID: 37443129 DOI: 10.1038/s41420-023-01545-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 06/12/2023] [Accepted: 07/04/2023] [Indexed: 07/15/2023] Open
Abstract
Diabetic Retinopathy (DR) is a complication of diabetes that causes blindness in adults. Retinal fibrosis is closely associated with developing proliferative diabetic retinopathy (PDR). Clinical studies have shown that fibrotic membranes exhibit uncontrolled growth in PDR and contribute to retinal detachment from RPE cells, ultimately leading to vision loss. While anti-VEGF agents and invasive laser treatments are the primary treatments for PDR, retinal fibrosis has received minimal attention as a potential target for therapeutic intervention. Therefore, to investigate the potential role of Akt2 in the diabetes-induced retinal fibrosis process, we generated RPE-specific Akt2 conditional knockout (cKO) mice and induced diabetes in these mice and Akt2fl/fl control mice by intraperitoneal injection of streptozotocin. After an 8-month duration of diabetes (10 months of age), the mice were euthanized and expression of tight junction proteins, epithelial-mesenchymal transition (EMT), and fibrosis markers were examined in the RPE. Diabetes induction in the floxed control mice decreased levels of the RPE tight junction protein ZO-1 and adherens junction proteins occludin and E-cadherin; these decreases were rescued in Akt2 cKO diabetic mice. Loss of Akt2 also inhibited diabetes-induced elevation of RNA and protein levels of the EMT markers Snail/Slug and Twist1 in the RPE as compared to Akt2fl/fl diabetic mice. We also found that in Akt2 cKO mice diabetes-induced increase of fibrosis markers, including collagen IV, Connective tissue growth factor (CTGF), fibronectin, and alpha-SMA was attenuated. Furthermore, we observed that high glucose-induced alterations in EMT and fibrosis markers in wild-type (WT) RPE explants were rescued in the presence of PI3K and ERK inhibitors, indicating diabetes-induced retinal fibrosis may be mediated via the PI3K/Akt2/ERK signaling, which could provide a novel target for DR therapy.
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Affiliation(s)
- Rachel Daley
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Vishnu Maddipatla
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Sayan Ghosh
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Olivia Chowdhury
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Stacey Hose
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - J Samuel Zigler
- Wilmer Eye Institute, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Debasish Sinha
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.
- Wilmer Eye Institute, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.
| | - Haitao Liu
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.
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12
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Yang J, Hua Z, Zheng Z, Ma X, Zhu L, Li Y. Acteoside inhibits high glucose-induced oxidative stress injury in RPE cells and the outer retina through the Keap1/Nrf2/ARE pathway. Exp Eye Res 2023; 232:109496. [PMID: 37268044 DOI: 10.1016/j.exer.2023.109496] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Revised: 04/20/2023] [Accepted: 05/03/2023] [Indexed: 06/04/2023]
Abstract
Diabetes retinopathy (DR) is one of the most common microvascular complications of diabetes. Retinal pigment epithelial (RPE) cells exposed to a high glucose environment experience a series of functional damages, which is an important factor in promoting the progression of DR. Acteoside (ACT) has strong antioxidant and anti-apoptotic properties, but the mechanism of ACT in DR is not completely clear. Therefore, the purpose of the present study was to explore whether ACT inhibits the damage to RPE cells in a high glucose environment through antioxidative effects to alleviate the DR process. The DR in vitro cell model was constructed by treating RPE cells with high glucose, and the DR in vivo animal model was constructed by injecting streptozotocin (STZ) into the peritoneal cavity of mice to induce diabetes. The proliferation and apoptosis of RPE cells were detected by CCK-8 and flow cytometry assays, respectively. The expression changes in Nrf2, Keap1, NQO1 and HO-1 were evaluated by qRT‒PCR, Western blot and immunohistochemistry analyses. The MDA, SOD, GSH-Px and T-AOC contents were detected by kits. The changes in ROS and nuclear translocation of Nrf2 were observed by immunofluorescence assays. HE staining was used to measure the thickness of the outer nuclear layer (ONL) of the retina, and TUNEL staining was used to detect the number of apoptotic cells in the retinas of mice. In the present study, ACT effectively ameliorated outer retina damage in diabetic mice. In high glucose (HG)-induced RPE cells, ACT treatment had the following effects: improved proliferation, decreased apoptosis, inhibited Keap1 expression, promoted the nuclear translocation and expression of Nrf2, upregulated NQO1 and HO-1 (the target genes of Nrf2) expression, decreased ROS concentration, and increased the levels of the SOD, GSH-Px and T-AOC antioxidant indicators. However, knockdown of Nrf2 reversed the above phenomena, which indicated that the protective function of ACT in HG-induced RPE cells are closely related to Nrf2. In summary, the present study demonstrated that HG-induced oxidative stress injury is inhibited by ACT in RPE cells and the outer retina through the Keap1/Nrf2/ARE pathway.
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Affiliation(s)
- Jingfei Yang
- Department of Ophthalmology, The First Affiliated Hospital of Kunming Medical University, Kunming, 650032, China; Department of Ophthalmology, The Affiliated Hospital of Yunnan University, Kunming, 650021, China
| | - Zhijuan Hua
- Department of Pediatric Ophthalmology, The Affiliated Hospital of Yunnan University, Kunming, 650021, China
| | - Zhikun Zheng
- Department of Ophthalmology, The Affiliated Hospital of Yunnan University, Kunming, 650021, China
| | - Xuan Ma
- Department of Ophthalmology, The Affiliated Hospital of Yunnan University, Kunming, 650021, China
| | - Liang Zhu
- Department of Ophthalmology, The First Affiliated Hospital of Kunming Medical University, Kunming, 650032, China
| | - Yan Li
- Department of Ophthalmology, The First Affiliated Hospital of Kunming Medical University, Kunming, 650032, China.
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Ji L, Waduge P, Wu Y, Huang C, Kaur A, Oliveira P, Tian H, Zhang J, Stout JT, Weng CY, Webster KA, Li W. Secretogranin III Selectively Promotes Vascular Leakage in the Deep Vascular Plexus of Diabetic Retinopathy. Int J Mol Sci 2023; 24:10531. [PMID: 37445707 PMCID: PMC10341987 DOI: 10.3390/ijms241310531] [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: 04/12/2023] [Revised: 06/12/2023] [Accepted: 06/20/2023] [Indexed: 07/15/2023] Open
Abstract
Diabetic retinopathy (DR), a leading cause of vision loss in working-age adults, induces mosaic patterns of vasculopathy that may be associated with spatial heterogeneity of intraretinal endothelial cells. We recently reported that secretogranin III (Scg3), a neuron-derived angiogenic and vascular leakage factor, selectively binds retinal vessels of diabetic but not healthy mice. Here, we investigated endothelial heterogeneity of three retinal vascular plexuses in DR pathogenesis and the therapeutic implications. Our unique in vivo ligand binding assay detected a 22.7-fold increase in Scg3 binding to retinal vessels of diabetic mice relative to healthy mice. Functional immunohistochemistry revealed that Scg3 predominantly binds to the DR-stressed CD31- deep retinal vascular plexus but not to the relatively healthy CD31+ superficial and intermediate plexuses within the same diabetic retina. In contrast, VEGF bound to healthy and diabetic retinal vessels indiscriminately with low activity. FITC-dextran assays indicated that selectively increased retinal vascular leakage coincides with Scg3 binding in diabetic mice that was independent of VEGF, whereas VEGF-induced leakage did not distinguish between diabetic and healthy mice. Dose-response curves showed that the anti-Scg3 humanized antibody (hAb) and anti-VEGF aflibercept alleviated DR leakage with equivalent efficacies, and that the combination acted synergistically. These findings suggest: (i) the deep plexus is highly sensitive to DR; (ii) Scg3 binding to the DR deep plexus coincides with the loss of CD31 and compromised endothelial junctions; (iii) anti-Scg3 hAb alleviates vascular leakage by selectively targeting the DR-stressed deep plexus within the same diabetic retina; (iv) combined anti-Scg3 and anti-VEGF treatments synergistically ameliorate DR through distinct mechanisms.
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Affiliation(s)
- Liyang Ji
- Cullen Eye Institute, Department of Ophthalmology, Baylor College of Medicine, Houston, TX 77030, USA
- Bascom Palmer Eye Institute, University of Miami School of Medicine, Miami, FL 33136, USA;
| | - Prabuddha Waduge
- Cullen Eye Institute, Department of Ophthalmology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Yan Wu
- Bascom Palmer Eye Institute, University of Miami School of Medicine, Miami, FL 33136, USA;
| | - Chengchi Huang
- Cullen Eye Institute, Department of Ophthalmology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Avinash Kaur
- Cullen Eye Institute, Department of Ophthalmology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Paola Oliveira
- Cullen Eye Institute, Department of Ophthalmology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Hong Tian
- Everglades Biopharma, LLC, Houston, TX 77098, USA
| | - Jinsong Zhang
- Department of Ophthalmology, The Fourth Affiliated Hospital of China Medical University, Shenyang 110005, China;
| | - J. Timothy Stout
- Cullen Eye Institute, Department of Ophthalmology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Christina Y. Weng
- Cullen Eye Institute, Department of Ophthalmology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Keith A. Webster
- Cullen Eye Institute, Department of Ophthalmology, Baylor College of Medicine, Houston, TX 77030, USA
- Everglades Biopharma, LLC, Houston, TX 77098, USA
| | - Wei Li
- Cullen Eye Institute, Department of Ophthalmology, Baylor College of Medicine, Houston, TX 77030, USA
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14
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Hernandez BJ, Skiba NP, Plößl K, Strain M, Grigsby D, Kelly U, Cady MA, Manocha V, Maminishkis A, Watkins T, Miller SS, Ashley-Koch A, Stamer WD, Weber BHF, Rickman CB, Klingeborn M. Polarized Desmosome and Hemidesmosome Shedding via Exosomes is an Early Indicator of Outer Blood-Retina Barrier Dysfunction. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.06.12.544677. [PMID: 37398366 PMCID: PMC10312606 DOI: 10.1101/2023.06.12.544677] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/04/2023]
Abstract
The retinal pigmented epithelium (RPE) constitutes the outer blood-retinal barrier, enables photoreceptor function of the eye, and is constantly exposed to oxidative stress. As such, dysfunction of the RPE underlies pathology leading to development of age-related macular degeneration (AMD), the leading cause of vision loss among the elderly in industrialized nations. A major responsibility of the RPE is to process photoreceptor outer segments, which relies on the proper functioning of its endocytic pathways and endosomal trafficking. Exosomes and other extracellular vesicles from RPE are an essential part of these pathways and may be early indicators of cellular stress. To test the role of exosomes that may underlie the early stages of AMD, we used a polarized primary RPE cell culture model under chronic subtoxic oxidative stress. Unbiased proteomic analyses of highly purified basolateral exosomes from oxidatively stressed RPE cultures revealed changes in proteins involved in epithelial barrier integrity. There were also significant changes in proteins accumulating in the basal-side sub-RPE extracellular matrix during oxidative stress, that could be prevented with an inhibitor of exosome release. Thus, chronic subtoxic oxidative stress in primary RPE cultures induces changes in exosome content, including basal-side specific desmosome and hemidesmosome shedding via exosomes. These findings provide novel biomarkers of early cellular dysfunction and opportunity for therapeutic intervention in age-related retinal diseases, (e.g., AMD) and broadly from blood-CNS barriers in other neurodegenerative diseases.
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15
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Lee D, Hong HS. Substance P Alleviates Retinal Pigment Epithelium Dysfunction Caused by High Glucose-Induced Stress. Life (Basel) 2023; 13:life13051070. [PMID: 37240715 DOI: 10.3390/life13051070] [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: 04/10/2023] [Accepted: 04/21/2023] [Indexed: 05/28/2023] Open
Abstract
When the retina is constantly affected by high glucose (HG) due to diabetes, the barrier function of the retinal pigment epithelium (RPE) is impaired, accompanied by unnecessary vascularization. This eventually leads to the development of diabetic retinopathy (DR). This study investigated the recovery effect of substance P (SP) on RPE injured by HG. RPE was treated with HG for 24 h, and HG-induced cellular injuries were confirmed. SP was added to the dysfunctional RPE. Compared to RPE in low glucose (LG) conditions, HG-damaged RPE had large, fibrotic cell shapes, and its cellular viability decreased. HG treatment reduced tight junction protein expression levels and caused oxidative stress by interrupting the antioxidant system; this was followed by inflammatory factor intracellular adhesion molecule-1 (ICAM-1), Monocyte chemotactic protein-1 (MCP-1), and angiogenesis factor vascular endothelial growth factor (VEGF) expression. SP treatment contributed to RPE recovery by enhancing cell viability, tight junction protein expression, and RPE function under HG conditions, possibly by activating the Akt signaling pathway. Importantly, SP treatment reduced ICAM-1, MCP-1, and VEGF expression. Collectively, SP activated survival signals to suppress oxidative stress and improve retinal barrier function in RPE, accompanied by immune suppression. This suggests the possible application of SP to diabetic retinal injuries.
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Affiliation(s)
- Dahyeon Lee
- Department of Biomedical Science and Technology, Graduate School, Kyung Hee University, Seoul 02447, Republic of Korea
| | - Hyun Sook Hong
- Department of Biomedical Science and Technology, Graduate School, Kyung Hee University, Seoul 02447, Republic of Korea
- East-West Medical Research Institute, Kyung Hee University, Seoul 02447, Republic of Korea
- Kyung Hee Institute of Regenerative Medicine (KIRM), Medical Science Research Institute, Kyung Hee University Medical Center, Seoul 02447, Republic of Korea
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16
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Hypoxia-induced transcriptional differences in African and Asian versus European diabetic cybrids. Sci Rep 2023; 13:3818. [PMID: 36882486 PMCID: PMC9992459 DOI: 10.1038/s41598-023-30518-x] [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: 07/22/2022] [Accepted: 02/24/2023] [Indexed: 03/09/2023] Open
Abstract
Diabetic retinopathy (DR) is the most common diabetic microvascular complication and cause of blindness in adults under the age of 65. Our results suggest that, when comparing transcriptomes of cultures grown in hypoxic conditions versus room-air, cybrids containing mitochondria from African and Asian diabetic subjects ([Afr + Asi]/DM) have some uniquely different transcriptome profiles compared to European/diabetic (Euro/DM) cybrids (e.g., fatty acid metabolism: EnrichR rank 10 in [Afr + Asi]/DM, rank 85 in Euro/DM; Endocytosis: rank 25 in [Afr + Asi]/DM, rank 5 in Euro/DM; Ubiquitin Mediated Proteolysis: rank 34 in [Afr + Asi]/DM, rank 7 in Euro/DM). As determined by both RNA-seq and qRT-PCR results, transcription of the gene encoding oleoyl-ACP hydrolase (OLAH) was significantly increased in [Afr + Asi]/DM cybrids compared to Euro/DM cybrids in hypoxic conditions. Additionally, our results show that in hypoxic conditions, Euro/DM cybrids and [Afr + Asi]/DM cybrids show similar decreases in ROS production. All cybrids showed decreased ZO1-minus protein levels, but their phagocytic functions were not significantly altered in hypoxic conditions. In conclusion, our findings suggest that the "molecular memory" imparted by [Afr + Asi]/DM mtDNA may act through one of the molecular pathways seen in transcriptome analysis, such as fatty acid metabolism, without significantly changing essential RPE functions.
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17
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Du J, Landa G. Impact of prior pars plana vitrectomy on development of cystoid macular edema after uneventful cataract surgery. J Cataract Refract Surg 2023; 49:266-271. [PMID: 36384754 DOI: 10.1097/j.jcrs.0000000000001097] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Accepted: 11/10/2022] [Indexed: 11/18/2022]
Abstract
PURPOSE To investigate whether a history of prior pars plana vitrectomy (PPV) for rhegmatogenous retinal detachment (RRD) predisposes to the development of pseudophakic cystoid macular edema (CME). SETTING New York Eye and Ear Infirmary of Mount Sinai, New York, New York. DESIGN Retrospective cohort study. METHODS Records of 365 subjects who underwent PPV for RRD and subsequent cataract surgery between 2017 and 2020 were reviewed. Patients with a history of diabetic retinopathy, inflammatory retinal vascular disease, uveitis, advanced age-related macular degeneration, intraocular infection, myopic maculopathy, or significant intraoperative complications precluding posterior chamber intraocular lens placement were excluded. Age-matched subjects who underwent routine cataract surgery served as controls. Clinical data and macular optical coherence tomography (OCT) findings up to 4 years postoperatively were obtained. RESULTS 54 eyes underwent uneventful cataract surgery by phacoemulsification and had a history of PPV with gas tamponade. 55 eyes underwent uneventful cataract surgery only. The average follow-up time after cataract surgery was 39.1 months. In eyes with a history of PPV, the incidence of OCT-detected CME was 27.8% (15/54) compared with 3.8% (2/55) in the control group ( P < .001) and the incidence of clinically significant CME was 18.5% (10/54) compared with 1.8% (1/55) in the control group ( P = .004). 80% (12/15) of CME cases were treated with topical therapy, and none required intravitreal injection. CONCLUSIONS Prior PPV for RRD is associated with an increased incidence of pseudophakic CME after uneventful cataract surgery. Prophylactic or prolonged postoperative anti-inflammatory topical therapy may be prudent to consider in these patients.
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Affiliation(s)
- Jeanette Du
- From the Department of Ophthalmology, New York Eye and Ear Infirmary of Mount Sinai, New York, New York (Du, Landa); Icahn School of Medicine at Mount Sinai, New York, New York (Landa)
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18
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Prasad R, Adu-Agyeiwaah Y, Floyd JL, Asare-Bediako B, Li Calzi S, Chakraborty D, Harbour A, Rohella A, Busik JV, Li Q, Grant MB. Sustained ACE2 Expression by Probiotic Improves Integrity of Intestinal Lymphatics and Retinopathy in Type 1 Diabetic Model. J Clin Med 2023; 12:jcm12051771. [PMID: 36902558 PMCID: PMC10003436 DOI: 10.3390/jcm12051771] [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: 02/05/2023] [Revised: 02/17/2023] [Accepted: 02/21/2023] [Indexed: 02/25/2023] Open
Abstract
Intestinal lymphatic, known as lacteal, plays a critical role in maintaining intestinal homeostasis by regulating several key functions, including the absorption of dietary lipids, immune cell trafficking, and interstitial fluid balance in the gut. The absorption of dietary lipids relies on lacteal integrity, mediated by button-like and zipper-like junctions. Although the intestinal lymphatic system is well studied in many diseases, including obesity, the contribution of lacteals to the gut-retinal axis in type 1 diabetes (T1D) has not been examined. Previously, we showed that diabetes induces a reduction in intestinal angiotensin-converting enzyme 2 (ACE2), leading to gut barrier disruption. However, when ACE2 levels are maintained, a preservation of gut barrier integrity occurs, resulting in less systemic inflammation and a reduction in endothelial cell permeability, ultimately retarding the development of diabetic complications, such as diabetic retinopathy. Here, we examined the impact of T1D on intestinal lymphatics and circulating lipids and tested the impact of intervention with ACE-2-expressing probiotics on key aspects of gut and retinal function. Akita mice with 6 months of diabetes were orally gavaged LP-ACE2 (3x/week for 3 months), an engineered probiotic (Lactobacillus paracasei; LP) expressing human ACE2. After three months, immunohistochemistry (IHC) was used to evaluate intestinal lymphatics, gut epithelial, and endothelial barrier integrity. Retinal function was assessed using visual acuity, electroretinograms, and enumeration of acellular capillaries. LP-ACE2 significantly restored intestinal lacteal integrity as assessed by the increased expression of lymphatic vessel hyaluronan receptor 1 (LYVE-1) expression in LP-ACE2-treated Akita mice. This was accompanied by improved gut epithelial (Zonula occludens-1 (ZO-1), p120-catenin) and endothelial (plasmalemma vesicular protein -1 (PLVAP1)) barrier integrity. In Akita mice, the LP-ACE2 treatment reduced plasma levels of LDL cholesterol and increased the expression of ATP-binding cassette subfamily G member 1 (ABCG1) in retinal pigment epithelial cells (RPE), the population of cells responsible for lipid transport from the systemic circulation into the retina. LP-ACE2 also corrected blood-retinal barrier (BRB) dysfunction in the neural retina, as observed by increased ZO-1 and decreased VCAM-1 expression compared to untreated mice. LP-ACE2-treated Akita mice exhibit significantly decreased numbers of acellular capillaries in the retina. Our study supports the beneficial role of LP-ACE2 in the restoration of intestinal lacteal integrity, which plays a key role in gut barrier integrity and systemic lipid metabolism and decreased diabetic retinopathy severity.
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Affiliation(s)
- Ram Prasad
- Department of Ophthalmology and Visual Sciences, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Yvonne Adu-Agyeiwaah
- Department of Ophthalmology and Visual Sciences, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Jason L. Floyd
- Department of Ophthalmology and Visual Sciences, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Bright Asare-Bediako
- Department of Ophthalmology and Visual Sciences, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Sergio Li Calzi
- Department of Ophthalmology and Visual Sciences, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Dibyendu Chakraborty
- Department of Ophthalmology and Visual Sciences, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Angela Harbour
- Department of Ophthalmology and Visual Sciences, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Aayush Rohella
- Department of Ophthalmology and Visual Sciences, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Julia V. Busik
- Department of Physiology, Michigan State University, East Lansing, MI 48824, USA
| | - Qiuhong Li
- Department of Ophthalmology, University of Florida, Gainesville, FL 32611, USA
| | - Maria B. Grant
- Department of Ophthalmology and Visual Sciences, University of Alabama at Birmingham, Birmingham, AL 35294, USA
- Correspondence: ; Tel.: +1-205-996-8685; Fax: +1-205-934-3425
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19
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Nowak MS, Żurek M, Grabska-Liberek I, Kanclerz P. First Nation-Wide Study of the Incidence and Characteristics of Retinal Detachment in Poland during 2013-2019. J Clin Med 2023; 12:jcm12041461. [PMID: 36835996 PMCID: PMC9958566 DOI: 10.3390/jcm12041461] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Revised: 02/06/2023] [Accepted: 02/09/2023] [Indexed: 02/16/2023] Open
Abstract
AIMS The present study aimed to analyze the incidence and characteristics of all types of retinal detachment (RD) in the overall population of Polish adults during 2013-2019. METHODS Data from all levels of healthcare services at public and private institutions recorded in the National Health Fund (NHF) database were evaluated. International Classification of Diseases codes (ICD-9 and ICD-10) and unique NHF codes were used to identify RD patients and RD treatment procedures. RESULTS In the period 2013-2019, 71,073 patients with RD were newly diagnosed in Poland. The average incidence was 32.64/100,000 person-years (95% CI: 31.28-33.99) and it increased with the age of patients, with the highest rate in the group of patients ≥70 years of age. The overall incidences of rhegmatogenous RD, traction RD, serous RD, other RD and unspecified RD were 13.72/100,000, 2.03/100,000, 1.02/100,000, 7.90/100,000 and 7.97/100,000 person-years, respectively. The most common surgical treatment for RD in Poland was PPV performed on average in 49.80% of RD patients. The risk factor analyses showed that rhegmatogenous RD was significantly associated with age (OR 1.026), male sex (OR 2.320), rural residence (OR 0.958), DM type 2 (OR 1.603), any DR (OR 2.109), myopia (OR 2.997), glaucoma (OR 2.169) and uveitis (OR 2.561). Traction RD was also significantly associated with age (OR 1.013) and male sex (OR 2.785) as well as with any DR (OR 2.493), myopia (OR 2.255), glaucoma (OR 1.904) and uveitis (OR 4.214). Serous RD was significantly associated with all analyzed risk factors except DM type 2. CONCLUSIONS The total incidence of retinal detachment in Poland was higher than found in previously published studies. Our study demonstrated that diabetes type 1 and diabetic retinopathy are risk factors of development of serous RD, which is presumably associated with the disruption of the blood-retinal barriers in these conditions.
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Affiliation(s)
- Michal Szymon Nowak
- Institute of Optics and Optometry, University of Social Science, 121 Gdanska Str., 90-519 Lodz, Poland
- Provisus Eye Clinic, 112 Redzinska Str., 42-209 Czestochowa, Poland
- Correspondence: ; Tel.: +48-888-80-10-10
| | - Michał Żurek
- Doctoral School, Medical University of Warsaw, 61 Zwirki and Wigury Str., 02-091 Warsaw, Poland
- Department of Analyses and Strategies, Ministry of Health, 15 Miodowa Str., 00-952 Warsaw, Poland
| | - Iwona Grabska-Liberek
- Department of Ophthalmology, Center of Postgraduate Medical Education, 231 Czerniakowska Str., 01-416 Warsaw, Poland
| | - Piotr Kanclerz
- Hygeia Medical Clinic, Department of Ophthalmology, 80-286 Gdansk, Poland
- Helsinki Retina Research Group, University of Helsinki, 00014 Helsinki, Finland
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20
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Hu J, Zhu M, Li D, Wu Q, Le YZ. Critical Role of VEGF as a Direct Regulator of Photoreceptor Function. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2023; 1415:487-491. [PMID: 37440076 DOI: 10.1007/978-3-031-27681-1_71] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/14/2023]
Abstract
Vascular endothelial growth factor (VEGF or VEGF-A), a major pathogenic factor for diabetic and hypoxic blood-retina barrier (BRB) diseases, has been shown to act as a direct functional regulator for neurons in the peripheral and central nerve systems. To determine if VEGF plays a direct role in regulating retinal neuronal function, we established specific experimental procedures and examined the effect of recombinant VEGF (rVEGF) on photoreceptor function with electroretinography (ERG) in mice. In our case, rVEGF caused a significant reduction of scotopic ERG a-wave and b-wave amplitudes and photopic ERG b-wave amplitudes in a dose-dependent manner in dark-adapted wild-type (WT) mice, shortly after the intravitreal delivery of rVEGF in dark. However, the effect of rVEGF on photoreceptor function was nullified in adult Akita diabetic mice. Our data strongly suggest that VEGF is a direct regulator of photoreceptor function and VEGF upregulation contributes significantly to the diabetes-induced reduction of photoreceptor function. In this chapter, we will discuss the relevant background, key experimental procedures and results, and clinical significance of our work.
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Affiliation(s)
- Jianyan Hu
- Department of Medicine/Endocrinology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
- Department of Ophthalmology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China
| | - Meili Zhu
- Department of Medicine/Endocrinology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Dai Li
- Department of Medicine/Endocrinology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
- School of Optometry, Hubei University of Science and Technology, Xianning, China
| | - Qiang Wu
- Department of Ophthalmology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China
- Shanghai Key Laboratory of Diabetes Mellitus, Shanghai, China
| | - Yun-Zheng Le
- Department of Medicine/Endocrinology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA.
- Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA.
- Department of Ophthalmology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA.
- Harold Hamm Diabetes Center, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA.
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21
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Orduna-Hospital E, Arcas-Carbonell M, Sanchez-Cano A, Pinilla I, Consejo A. Speckle Contrast as Retinal Tissue Integrity Biomarker in Patients with Type 1 Diabetes Mellitus with No Retinopathy. J Pers Med 2022; 12:jpm12111807. [PMID: 36579516 PMCID: PMC9693211 DOI: 10.3390/jpm12111807] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Revised: 10/25/2022] [Accepted: 10/28/2022] [Indexed: 11/06/2022] Open
Abstract
PURPOSE To study the retinal and choroidal layers in type 1 diabetes mellitus (DM1) without diabetic retinopathy (DR), using speckle contrast of optical coherence tomography (OCT) images as a tissue biomarker in comparison with healthy subjects. METHODS OCT Spectralis images of 148 eyes, 84 from DM1 patients without DR signs, and 64 belonging to the control group, were collected. The speckle contrast and thickness of the inner retinal layer (IRL), the outer retinal layer (ORL), and the choroidal layer in the nasal parafoveal area (N3), were prospectively analyzed. RESULTS A statistically significant difference (p = 0.001) in the IRL thickness between groups was observed, being thicker in the DM1 group. There were no differences in the ORL and choroidal thicknesses between groups. A statistically significant difference (p = 0.02) in the IRL speckle contrast was obtained, being lower in the DM1 group. The maximum speckle contrast was reached in the ORL for both groups, although in the DM1 group, it occurs closer to the choroid, at 64 ± 8 μm (p = 0.008). CONCLUSIONS Statistically significant differences were found in speckle contrast and thickness between the control and the DM1 group, suggesting an IRL alteration of DM1 patients, supporting the retinal neurodegeneration before DR signs are observed.
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Affiliation(s)
- Elvira Orduna-Hospital
- Department of Applied Physics, University of Zaragoza, 50009 Zaragoza, Spain
- Aragon Institute for Health Research (IIS Aragon), 50009 Zaragoza, Spain
- Correspondence:
| | | | - Ana Sanchez-Cano
- Department of Applied Physics, University of Zaragoza, 50009 Zaragoza, Spain
- Aragon Institute for Health Research (IIS Aragon), 50009 Zaragoza, Spain
| | - Isabel Pinilla
- Aragon Institute for Health Research (IIS Aragon), 50009 Zaragoza, Spain
- Department of Ophthalmology, Lozano Blesa University Hospital, 50009 Zaragoza, Spain
- Department of Surgery, University of Zaragoza, 50009 Zaragoza, Spain
| | - Alejandra Consejo
- Department of Applied Physics, University of Zaragoza, 50009 Zaragoza, Spain
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22
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An Update on Suprachoroidal Corticosteroid Injections in the Management of Macular Edema. CURRENT OPHTHALMOLOGY REPORTS 2022. [DOI: 10.1007/s40135-022-00291-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
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23
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Shityakov S, Nagai M, Ergün S, Braunger BM, Förster CY. The Protective Effects of Neurotrophins and MicroRNA in Diabetic Retinopathy, Nephropathy and Heart Failure via Regulating Endothelial Function. Biomolecules 2022; 12:biom12081113. [PMID: 36009007 PMCID: PMC9405668 DOI: 10.3390/biom12081113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Revised: 08/05/2022] [Accepted: 08/11/2022] [Indexed: 12/15/2022] Open
Abstract
Diabetes mellitus is a common disease affecting more than 537 million adults worldwide. The microvascular complications that occur during the course of the disease are widespread and affect a variety of organ systems in the body. Diabetic retinopathy is one of the most common long-term complications, which include, amongst others, endothelial dysfunction, and thus, alterations in the blood-retinal barrier (BRB). This particularly restrictive physiological barrier is important for maintaining the neuroretina as a privileged site in the body by controlling the inflow and outflow of fluid, nutrients, metabolic end products, ions, and proteins. In addition, people with diabetic retinopathy (DR) have been shown to be at increased risk for systemic vascular complications, including subclinical and clinical stroke, coronary heart disease, heart failure, and nephropathy. DR is, therefore, considered an independent predictor of heart failure. In the present review, the effects of diabetes on the retina, heart, and kidneys are described. In addition, a putative common microRNA signature in diabetic retinopathy, nephropathy, and heart failure is discussed, which may be used in the future as a biomarker to better monitor disease progression. Finally, the use of miRNA, targeted neurotrophin delivery, and nanoparticles as novel therapeutic strategies is highlighted.
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Affiliation(s)
- Sergey Shityakov
- Division of Chemoinformatics, Infochemistry Scientific Center, Lomonosova Street 9, 191002 Saint-Petersburg, Russia
| | - Michiaki Nagai
- Department of Cardiology, Hiroshima City Asa Hospital, 2-1-1 Kabeminami, Aaskita-ku, Hiroshima 731-0293, Japan
| | - Süleyman Ergün
- Institute of Anatomy and Cell Biology, Julius-Maximilians-University Würzburg, 97070 Würzburg, Germany
| | - Barbara M. Braunger
- Institute of Anatomy and Cell Biology, Julius-Maximilians-University Würzburg, 97070 Würzburg, Germany
- Correspondence: (B.M.B.); (C.Y.F.)
| | - Carola Y. Förster
- Department of Anaesthesiology, Intensive Care, Emergency and Pain Medicine, Würzburg University, 97080 Würzburg, Germany
- Correspondence: (B.M.B.); (C.Y.F.)
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24
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Lechner J, Medina RJ, Lois N, Stitt AW. Advances in cell therapies using stem cells/progenitors as a novel approach for neurovascular repair of the diabetic retina. Stem Cell Res Ther 2022; 13:388. [PMID: 35907890 PMCID: PMC9338609 DOI: 10.1186/s13287-022-03073-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Accepted: 07/20/2022] [Indexed: 11/26/2022] Open
Abstract
BACKGROUND Diabetic retinopathy, a major complication of diabetes mellitus, is a leading cause of sigh-loss in working age adults. Progressive loss of integrity of the retinal neurovascular unit is a central element in the disease pathogenesis. Retinal ischemia and inflammatory processes drive interrelated pathologies such as blood retinal barrier disruption, fluid accumulation, gliosis, neuronal loss and/or aberrant neovascularisation. Current treatment options are somewhat limited to late-stages of the disease where there is already significant damage to the retinal architecture arising from degenerative, edematous and proliferative pathology. New preventive and interventional treatments to target early vasodegenerative and neurodegenerative stages of the disease are needed to ensure avoidance of sight-loss. MAIN BODY Historically, diabetic retinopathy has been considered a primarily microvascular disease of the retina and clinically it is classified based on the presence and severity of vascular lesions. It is now known that neurodegeneration plays a significant role during the pathogenesis. Loss of neurons has been documented at early stages in pre-clinical models as well as in individuals with diabetes and, in some, even prior to the onset of clinically overt diabetic retinopathy. Recent studies suggest that some patients have a primarily neurodegenerative phenotype. Retinal pigment epithelial cells and the choroid are also affected during the disease pathogenesis and these tissues may also need to be addressed by new regenerative treatments. Most stem cell research for diabetic retinopathy to date has focused on addressing vasculopathy. Pre-clinical and clinical studies aiming to restore damaged vasculature using vasoactive progenitors including mesenchymal stromal/stem cells, adipose stem cells, CD34+ cells, endothelial colony forming cells and induced pluripotent stem cell derived endothelial cells are discussed in this review. Stem cells that could replace dying neurons such as retinal progenitor cells, pluripotent stem cell derived photoreceptors and ganglion cells as well as Müller stem cells are also discussed. Finally, challenges of stem cell therapies relevant to diabetic retinopathy are considered. CONCLUSION Stem cell therapies hold great potential to replace dying cells during early and even late stages of diabetic retinopathy. However, due to the presence of different phenotypes, selecting the most suitable stem cell product for individual patients will be crucial for successful treatment.
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Affiliation(s)
- Judith Lechner
- Wellcome-Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry, and Biomedical Science, Queen's University Belfast, Belfast, UK.
| | - Reinhold J Medina
- Wellcome-Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry, and Biomedical Science, Queen's University Belfast, Belfast, UK
| | - Noemi Lois
- Wellcome-Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry, and Biomedical Science, Queen's University Belfast, Belfast, UK
| | - Alan W Stitt
- Wellcome-Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry, and Biomedical Science, Queen's University Belfast, Belfast, UK.
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25
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Molins B, Mesquida M, Adan A. Bioengineering approaches for modelling retinal pathologies of the outer blood-retinal barrier. Prog Retin Eye Res 2022:101097. [PMID: 35840488 DOI: 10.1016/j.preteyeres.2022.101097] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 05/31/2022] [Accepted: 06/29/2022] [Indexed: 11/18/2022]
Abstract
Alterations of the junctional complex of the outer blood-retinal barrier (oBRB), which is integrated by the close interaction of the retinal pigment epithelium, the Bruch's membrane, and the choriocapillaris, contribute to the loss of neuronal signalling and subsequent vision impairment in several retinal inflammatory disorders such as age-related macular degeneration and diabetic retinopathy. Reductionist approaches into the mechanisms that underlie such diseases have been hindered by the absence of adequate in vitro models using human cells to provide the 3D dynamic architecture that enables expression of the in vivo phenotype of the oBRB. Conventional in vitro cell models are based on 2D monolayer cellular cultures, unable to properly recapitulate the complexity of living systems. The main drawbacks of conventional oBRB models also emerge from the cell sourcing, the lack of an appropriate Bruch's membrane analogue, and the lack of choroidal microvasculature with flow. In the last years, the advent of organ-on-a-chip, bioengineering, and stem cell technologies is providing more advanced 3D models with flow, multicellularity, and external control over microenvironmental properties. By incorporating additional biological complexity, organ-on-a-chip devices can mirror physiologically relevant properties of the native tissue while offering additional set ups to model and study disease. In this review we first examine the current understanding of oBRB biology as a functional unit, highlighting the coordinated contribution of the different components to barrier function in health and disease. Then we describe recent advances in the use of pluripotent stem cells-derived retinal cells, Bruch's membrane analogues, and co-culture techniques to recapitulate the oBRB. We finally discuss current advances and challenges of oBRB-on-a-chip technologies for disease modelling.
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Affiliation(s)
- Blanca Molins
- Group of Ocular Inflammation: Clinical and Experimental Studies, Institut d'Investigacions Biomèdiques Agustí Pi I Sunyer (IDIBAPS), C/ Sabino de Arana 1, 08028, Barcelona, Spain.
| | - Marina Mesquida
- Group of Ocular Inflammation: Clinical and Experimental Studies, Institut d'Investigacions Biomèdiques Agustí Pi I Sunyer (IDIBAPS), C/ Sabino de Arana 1, 08028, Barcelona, Spain; Roche Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., Basel, Switzerland
| | - Alfredo Adan
- Group of Ocular Inflammation: Clinical and Experimental Studies, Institut d'Investigacions Biomèdiques Agustí Pi I Sunyer (IDIBAPS), C/ Sabino de Arana 1, 08028, Barcelona, Spain; Instituto Clínic de Oftalmología, Hospital Clínic Barcelona, C/ Sabino de Arana 1, 08028, Barcelona, Spain
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26
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Correlation between Choroidal Vascularity Index and Outer Retina in Patients with Diabetic Retinopathy. J Clin Med 2022; 11:jcm11133882. [PMID: 35807164 PMCID: PMC9267134 DOI: 10.3390/jcm11133882] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Revised: 06/26/2022] [Accepted: 07/01/2022] [Indexed: 02/04/2023] Open
Abstract
The choroid supplies blood to the outer retina. We quantified outer retinal and choroidal parameters to understand better the pathogenesis of diabetic retinopathy (DR) and diabetic macular edema (DME). The retrospective cross-sectional single-center study included 210 eyes from 139 diabetic patients and 76 eyes from 52 healthy controls. Spectral-domain optical coherence tomography (OCT) was carried out with a Spectralis HRA + OCT imaging device. The outer retinal layer (ORL), outer nuclear layer (ONL), and choroidal thicknesses were assessed along with the choroidal vascularity index (CVI). The presence of DR, whether with DME or without, was associated with choroidal thinning (p < 0.001). Compared with the controls, patients with DR without DME presented with lower ORL and ONL thickness (p < 0.001), whereas those with DR and DME had higher values of both parameters (p < 0.001). Significant correlations between outer retinal and choroidal parameters were found only in patients with DR without DME (ORL with choroidal thickness: p = 0.003, rho = 0.34; ORL with CVI: p < 0.001, rho = 0.49, ONL with CVI: p < 0.027, rho = 0.25). No correlations between choroidal and outer retinal parameters were observed in the controls and patients with DR and concomitant DME. Aside from diabetic choroidopathy, other pathogenic mechanisms seem to predominate in the latter group.
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27
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Malhi NK, Allen CL, Stewart E, Horton KL, Riu F, Batson J, Amoaku W, Morris JC, Arkill KP, Bates DO. Serine-arginine-rich protein kinase-1 inhibition for the treatment of diabetic retinopathy. Am J Physiol Heart Circ Physiol 2022; 322:H1014-H1027. [PMID: 35302878 PMCID: PMC9109797 DOI: 10.1152/ajpheart.00001.2022] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Angiogenic VEGF isoforms are upregulated in diabetic retinopathy (DR), driving pathological growth and fluid leakage. Serine-arginine-rich protein kinase-1 (SRPK1) regulates VEGF splicing, and its inhibition blocks angiogenesis. We tested the hypothesis that SRPK1 is activated in diabetes, and an SRPK1 inhibitor (SPHINX31) switches VEGF splicing in DR and prevents increased vascular permeability into the retina. SRPK1 was activated by high glucose (HG), in a PKC-dependent manner, and was blocked by SPHINX31. HG induced release of SRSF1 from the nuclear speckles, which was also SRPK1 dependent, and increased retinal pigment epithelial (RPE) monolayer admittance, which was reversed by SRPK1 inhibition (P < 0.05). Diabetes increased retinal permeability and thickness after 14 days which was blocked by treatment with SPHINX31 eye drops (P < 0.0001). These results show that SRPK1 inhibition, administered as an eye drop, protected the retinal barrier from hyperglycemia-associated loss of integrity in RPE cells in vitro and in diabetic rats in vivo. A clinical trial of another SRPK1 inhibitor has now been initiated in patients with diabetic macular edema.NEW & NOTEWORTHY VEGF-A165b splicing is induced by hyperglycemia through PKC-mediated activation of SRPK1 in RPE cells, increasing their permeability and angiogenic capability. SRPK1 inhibitors can be given as eye drops to reduce retinal permeability and edema in diabetic retinopathy.
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Affiliation(s)
- Naseeb K Malhi
- Tumour and Vascular Biology Laboratories, Division of Cancer and Stem Cells, Centre for Cancer Sciences, School of Medicine, Biodiscovery Institute, University of Nottingham, Nottingham, United Kingdom
| | - Claire L Allen
- Tumour and Vascular Biology Laboratories, Division of Cancer and Stem Cells, Centre for Cancer Sciences, School of Medicine, Biodiscovery Institute, University of Nottingham, Nottingham, United Kingdom
| | | | - Katherine L Horton
- Tumour and Vascular Biology Laboratories, Division of Cancer and Stem Cells, Centre for Cancer Sciences, School of Medicine, Biodiscovery Institute, University of Nottingham, Nottingham, United Kingdom
| | - Federica Riu
- Tumour and Vascular Biology Laboratories, Division of Cancer and Stem Cells, Centre for Cancer Sciences, School of Medicine, Biodiscovery Institute, University of Nottingham, Nottingham, United Kingdom
| | | | - Winfried Amoaku
- Division of Clinical Neuroscience, Department of Ophthalmology, School of Medicine, University of Nottingham, Nottingham, United Kingdom
| | - Jonathan C Morris
- School of Chemistry, University of New South Wales, Sydney, New South Wales, Australia
| | - Kenton P Arkill
- Tumour and Vascular Biology Laboratories, Division of Cancer and Stem Cells, Centre for Cancer Sciences, School of Medicine, Biodiscovery Institute, University of Nottingham, Nottingham, United Kingdom
| | - David O Bates
- Tumour and Vascular Biology Laboratories, Division of Cancer and Stem Cells, Centre for Cancer Sciences, School of Medicine, Biodiscovery Institute, University of Nottingham, Nottingham, United Kingdom.,Exonate Limited, Duxford, United Kingdom.,COMPARE, University of Birmingham and University of Nottingham Midlands, Nottingham, United Kingdom
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28
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The essential role of N6-methyladenosine RNA methylation in complex eye diseases. Genes Dis 2022; 10:505-520. [DOI: 10.1016/j.gendis.2022.05.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2022] [Revised: 04/29/2022] [Accepted: 05/08/2022] [Indexed: 11/20/2022] Open
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29
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Carpi-Santos R, de Melo Reis RA, Gomes FCA, Calaza KC. Contribution of Müller Cells in the Diabetic Retinopathy Development: Focus on Oxidative Stress and Inflammation. Antioxidants (Basel) 2022; 11:antiox11040617. [PMID: 35453302 PMCID: PMC9027671 DOI: 10.3390/antiox11040617] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Revised: 03/01/2022] [Accepted: 03/15/2022] [Indexed: 01/27/2023] Open
Abstract
Diabetic retinopathy is a neurovascular complication of diabetes and the main cause of vision loss in adults. Glial cells have a key role in maintenance of central nervous system homeostasis. In the retina, the predominant element is the Müller cell, a specialized cell with radial morphology that spans all retinal layers and influences the function of the entire retinal circuitry. Müller cells provide metabolic support, regulation of extracellular composition, synaptic activity control, structural organization of the blood–retina barrier, antioxidant activity, and trophic support, among other roles. Therefore, impairments of Müller actions lead to retinal malfunctions. Accordingly, increasing evidence indicates that Müller cells are affected in diabetic retinopathy and may contribute to the severity of the disease. Here, we will survey recently described alterations in Müller cell functions and cellular events that contribute to diabetic retinopathy, especially related to oxidative stress and inflammation. This review sheds light on Müller cells as potential therapeutic targets of this disease.
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Affiliation(s)
- Raul Carpi-Santos
- Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, RJ, Brazil; (R.C.-S.); (F.C.A.G.)
| | - Ricardo A. de Melo Reis
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, RJ, Brazil;
| | - Flávia Carvalho Alcantara Gomes
- Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, RJ, Brazil; (R.C.-S.); (F.C.A.G.)
| | - Karin C. Calaza
- Instituto de Biologia, Departamento de Neurobiologia, Universidade Federal Fluminense, Niteroi 24210-201, RJ, Brazil
- Correspondence:
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30
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Jiang X, Liu Y, Wang Y, Zhou Y, Miao H, Zhang P, Ma J. Long non‑coding RNA MALAT1 is involved in retinal pigment epithelial cell damage caused by high glucose treatment. Mol Med Rep 2022; 25:177. [PMID: 35315497 DOI: 10.3892/mmr.2022.12693] [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: 12/26/2021] [Accepted: 03/02/2022] [Indexed: 11/06/2022] Open
Abstract
The present study aimed to explore the role of long non‑coding RNA metastasis associated lung adenocarcinoma transcript 1 (lncRNA MALAT1) in high glucose (HG)‑induced ARPE‑19 cell damage. ARPE‑19 cells were cultured and treated with HG (25 mmol/l glucose). MALAT1 expression was silenced following transfection of small interfering RNA. Cell apoptosis was measured using flow cytometry. The cellular levels of reactive oxygen species (ROS), malondialdehyde and superoxide dismutase activity were all measured to examine oxidative stress. Gene expression levels of MALAT1 were determined by reverse transcription‑quantitative (RT‑q)PCR, while expression of tumor necrosis factor (TNF)‑α, monocyte chemotactic protein 1 (MCP‑1), intercellular cell adhesion molecule 1 (ICAM‑1) and vascular endothelial growth factor (VEGF) was detected using RT‑qPCR and western blotting. MALAT1 expression was markedly increased in ARPE‑19 cells treated with HG. HG treatment caused increased apoptosis and elevated ROS‑induced stress in ARPE‑19 cells and these effects could be partly attenuated by MALAT1 knockdown. Increased gene expression levels of TNF‑α, MCP‑1, ICAM‑1 and VEGF induced by HG were also alleviated by MALAT1 inhibition. Therefore, lncRNA MALAT1 is the key factor in ARPE‑19 cell damage caused by HG and may be a promising therapeutic target for clinical DR therapy. However, further studies are still required to reveal the detailed mechanisms underlying lncRNA MALAT1 function.
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Affiliation(s)
- Xinli Jiang
- Department of Ophthalmology, The Third Hospital of Hebei Medical University, Shijiazhuang, Hebei 050051, P.R. China
| | - Yan Liu
- Department of Endocrinology, The Third Hospital of Hebei Medical University, Shijiazhuang, Hebei 050051, P.R. China
| | - Yuling Wang
- Department of Neurology, The Third Hospital of Hebei Medical University, Shijiazhuang, Hebei 050051, P.R. China
| | - Yaru Zhou
- Department of Endocrinology, The Third Hospital of Hebei Medical University, Shijiazhuang, Hebei 050051, P.R. China
| | - Huipeng Miao
- Department of Ophthalmology, The Third Hospital of Hebei Medical University, Shijiazhuang, Hebei 050051, P.R. China
| | - Peng Zhang
- Department of Ophthalmology, The Third Hospital of Hebei Medical University, Shijiazhuang, Hebei 050051, P.R. China
| | - Jingxue Ma
- Department of Ophthalmology, The Second Hospital of Hebei Medical University, Shijiazhuang, Hebei 050000, P.R. China
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31
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Canovai A, Amato R, Melecchi A, Dal Monte M, Rusciano D, Bagnoli P, Cammalleri M. Preventive Efficacy of an Antioxidant Compound on Blood Retinal Barrier Breakdown and Visual Dysfunction in Streptozotocin-Induced Diabetic Rats. Front Pharmacol 2022; 12:811818. [PMID: 35046830 PMCID: PMC8762314 DOI: 10.3389/fphar.2021.811818] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Accepted: 12/06/2021] [Indexed: 12/13/2022] Open
Abstract
In diabetic retinopathy (DR), high blood glucose drives chronic oxidative stress and inflammation that trigger alterations of the neurovascular balance finally resulting in vascular abnormalities and retinal cell death, which converge towards altered electroretinogram (ERG). In the last years, a growing body of preclinical evidence has suggested that nutrients with anti-inflammatory/antioxidant properties can be able to hamper DR progression since its very early stages. In the present study, we used a streptozotocin-induced rat model of DR, which mimics most aspects of the early stages of human DR, to test the preventive efficacy of a novel compound containing cyanidin-3-glucoside (C3G), verbascoside and zinc as nutrients with antioxidant and anti-inflammatory properties. Western blot, immunofluorescence and electroretinographic analyses demonstrated a dose-dependent inhibition of oxidative stress- and inflammation-related mechanisms, with a significant counterpart in preventing molecular mechanisms leading to DR-associated vasculopathy and its related retinal damage. Preventive efficacy of the compound on dysfunctional a- and b-waves was also demonstrated by electroretinography. The present demonstration that natural compounds, possibly as a consequence of vascular rescue following ameliorated oxidative stress and inflammation, may prevent the apoptotic cascade leading to ERG dysfunction, adds further relevance to the potential application of antioxidants as a preventive therapy to counteract DR progression.
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Affiliation(s)
| | - Rosario Amato
- Department of Biology, University of Pisa, Pisa, Italy
| | | | - Massimo Dal Monte
- Department of Biology, University of Pisa, Pisa, Italy.,Interdepartmental Research Center Nutrafood "Nutraceuticals and Food for Health", University of Pisa, Pisa, Italy
| | | | - Paola Bagnoli
- Department of Biology, University of Pisa, Pisa, Italy
| | - Maurizio Cammalleri
- Department of Biology, University of Pisa, Pisa, Italy.,Interdepartmental Research Center Nutrafood "Nutraceuticals and Food for Health", University of Pisa, Pisa, Italy
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32
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Zhang Y, Meng X, Liu K. The modulation of cAMP/PKA pathway by asiaticoside ameliorates high glucose-induced inflammation and apoptosis of retinal pigment epithelial cells. J Bioenerg Biomembr 2022; 54:9-16. [PMID: 35038080 DOI: 10.1007/s10863-021-09929-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Accepted: 12/03/2021] [Indexed: 01/19/2023]
Abstract
Asiaticoside, the major bioactive constituent purified from Centella asiatica, is a pentacyclic triterpene saponin with sugar moieties (glucose-glucose-rhamnose). Its biological activities including anti-inflammation and antioxidant have been widely reported. This study aimed to investigate the role of asiaticoside in diabetic retinopathy (DR). Human retinal pigment epithelium (RPE) cells ARPE-19 were induced by high glucose. Then, cell survival rate, expression of inflammatory factors, oxidative stress, and apoptosis were measured by MTT method, western blot, oxidative stress detection kits and TUNEL respectively. To uncover the underlying mechanism, the levels of cyclic AMP (cAMP) and protein kinase A (PKA) were measured by Enzyme linked immunosorbent assay (ELISA) and PKA activities were detected by the Kemptide phosphorylation assay. Furthermore, cAMP inhibitor SQ22536 was also used to validate the mechanism. Asiaticoside suppressed the inflammation and apoptosis of ARPE-19 cells, and the activities of cAMP and PKA were inhibited upon HG induction while again released after further administration of asiaticoside. However, these effects were all abolished by SQ22536. In conclusion, we have demonstrated in this paper that asiaticoside ameliorates high glucose-induced inflammation and apoptosis of RPE cells by activating cAMP/PKA signaling pathway. asiaticoside-mediated activation of cAMP/PKA signaling pathway may serve as a potential target for the management of DR.
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Affiliation(s)
- Yixia Zhang
- Department of Ophthalmology, Wanzhou aier eye hospital, Chongqing, 404100, China
| | - Xindan Meng
- Department of Ophthalmology, Wanzhou aier eye hospital, Chongqing, 404100, China
| | - Keyu Liu
- Department of Surgery, Northern Kuanren Hospital, The Second Affiliated Hospital of Chongqing Medical University, Yubei District, 69 Renhe Xingguang Avenue, Chongqing, 401120, China.
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Prasad R, Asare-Bediko B, Harbour A, Floyd JL, Chakraborty D, Duan Y, Lamendella R, Wright J, Grant MB. Microbial Signatures in The Rodent Eyes With Retinal Dysfunction and Diabetic Retinopathy. Invest Ophthalmol Vis Sci 2022; 63:5. [PMID: 34985498 PMCID: PMC8742510 DOI: 10.1167/iovs.63.1.5] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Purpose The gut microbiome has been linked to disease pathogenesis through their interaction in metabolic, endocrine, and immune functions. The goal of this study was to determine whether the gut and plasma microbiota could transfer microbes to the retina in type 1 diabetic mice with retinopathy. Methods We analyzed the fecal, plasma, whole globe, and retina microbiome in Akita mice and compared with age-matched wild-type (WT) mice using 16S rRNA sequencing and metatranscriptomic analysis. To eliminate the contribution of the ocular surface and plasma microbiome, mice were perfused with sterile saline solution, the whole globes were extracted, and the neural retina was removed under sterile conditions for retinal microbiome. Results Our microbiome analysis revealed that Akita mice demonstrated a distinct pattern of microbes within each source: feces, plasma, whole globes, and retina. WT mice and Akita mice experienced transient bacteremia in the plasma and retina. Bacteria were identified in the retina of the Akita mice, specifically Corynebacterium, Pseudomonas, Lactobacillus, Staphylococcus, Enterococcus, and Bacillus. Significantly increased levels of peptidoglycan (0.036 ± 0.001 vs. 0.023 ± 0.002; P < 0.002) and TLR2 (3.47 ± 0.15 vs. 1.99 ± 0.07; P < 0.0001) were observed in the retina of Akita mice compared to WT. Increased IBA+ cells in the retina, reduced a- and b-waves on electroretinography, and increased acellular capillary formation demonstrated the presence of retinopathy in the Akita cohort compared to WT mice. Conclusions Together, our findings suggest that transient bacteremia exists in the plasma and retina of both cohorts. The bacteria found in Akita mice are distinct from WT mice and may contribute to development of retinal inflammation and barrier dysfunction in retinopathy.
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Affiliation(s)
- Ram Prasad
- Department of Ophthalmology and Visual Sciences, University of Alabama at Birmingham, Birmingham, Alabama, United States
| | - Bright Asare-Bediko
- Department of Ophthalmology and Visual Sciences, University of Alabama at Birmingham, Birmingham, Alabama, United States
| | - Angela Harbour
- Department of Ophthalmology and Visual Sciences, University of Alabama at Birmingham, Birmingham, Alabama, United States
| | - Jason L Floyd
- Department of Ophthalmology and Visual Sciences, University of Alabama at Birmingham, Birmingham, Alabama, United States
| | - Dibyendu Chakraborty
- Department of Ophthalmology and Visual Sciences, University of Alabama at Birmingham, Birmingham, Alabama, United States
| | - Yaqian Duan
- Department of Anatomy, Cell Biology & Physiology, Indiana University School of Medicine, Indianapolis, Indiana, United States.,Department of Endocrinology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | | | - Justin Wright
- Wright Labs, LLC, Huntingdon, Pennsylvania, United States
| | - Maria B Grant
- Department of Ophthalmology and Visual Sciences, University of Alabama at Birmingham, Birmingham, Alabama, United States
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34
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Rudraraju M, Narayanan SP, Somanath PR. Distinct Mechanisms of Human Retinal Endothelial Barrier Modulation In Vitro by Mediators of Diabetes and Uveitis. Life (Basel) 2021; 12:life12010033. [PMID: 35054426 PMCID: PMC8779223 DOI: 10.3390/life12010033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Revised: 11/30/2021] [Accepted: 12/10/2021] [Indexed: 12/04/2022] Open
Abstract
Ocular diseases such as diabetic retinopathy (DR) and uveitis are associated with injury to the blood–retinal barrier (BRB). Whereas high glucose (HG) and advanced glycation end products (AGE) contribute to DR, bacterial infections causing uveitis are triggered by endotoxins such as lipopolysaccharide (LPS). It is unclear how HG, AGE, and LPS affect human retinal endothelial cell (HREC) junctions. Moreover, tumor necrosis factor-α (TNFα) is elevated in both DR and ocular infections. In the current study, we determined the direct effects of HG, AGE, TNFα, and LPS on the expression and intracellular distribution of claudin-5, VE-cadherin, and β-catenin in HRECs and how these mediators affect Akt and P38 MAP kinase that have been implicated in ocular pathologies. In our results, whereas HG, AGE, and TNFα activated both Akt and P38 MAPK, LPS treatment suppressed Akt but increased P38 MAPK phosphorylation. Furthermore, while treatment with AGE and HG increased cell-junction protein expression in HRECs, LPS elicited a paradoxical effect. By contrast, when HG treatment increased HREC-barrier resistance, AGE and LPS stimulation compromised it, and TNFα had no effect. Together, our results demonstrated the differential effects of the mediators of diabetes and infection on HREC-barrier modulation leading to BRB injury.
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Affiliation(s)
- Madhuri Rudraraju
- Clinical and Experimental Therapeutics, College of Pharmacy, University of Georgia, Augusta, GA 30912, USA;
- Research Division, Charlie Norwood VA Medical Center, Augusta, GA 30912, USA
| | - S. Priya Narayanan
- Clinical and Experimental Therapeutics, College of Pharmacy, University of Georgia, Augusta, GA 30912, USA;
- Research Division, Charlie Norwood VA Medical Center, Augusta, GA 30912, USA
- Vascular Biology Center, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
- Vision Discovery Institute, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
- Correspondence: (S.P.N.); (P.R.S.); Tel.: +1-706-721-4250 (P.R.S.)
| | - Payaningal R. Somanath
- Clinical and Experimental Therapeutics, College of Pharmacy, University of Georgia, Augusta, GA 30912, USA;
- Research Division, Charlie Norwood VA Medical Center, Augusta, GA 30912, USA
- Vascular Biology Center, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
- Correspondence: (S.P.N.); (P.R.S.); Tel.: +1-706-721-4250 (P.R.S.)
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35
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Xu M, Jiang Y, Su L, Chen X, Shao X, Ea V, Shang Z, Zhang X, Barnstable CJ, Li X, Tombran-Tink J. Novel Regulators of Retina Neovascularization: A Proteomics Approach. J Proteome Res 2021; 21:101-117. [PMID: 34919406 DOI: 10.1021/acs.jproteome.1c00547] [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] [Indexed: 12/12/2022]
Abstract
The purpose of this study was to identify proteins that regulate vascular remodeling in an ROP mouse model. Pups were subjected to fluctuating oxygen levels and retinas sampled during vessel regression (PN12) or neovascularization (PN17) for comparative SWATH-MS proteomics using liquid chromatography-tandem mass spectrometry (LC-MS/MS). We developed a human retinal endothelial cell (HREC) ROP correlate to validate the expression of retina neovascular-specific markers. A total of 5191 proteins were identified in OIR retinas with 498 significantly regulated in elevated oxygen and 345 after a return to normoxia. A total of 122 proteins were uniquely regulated during vessel regression and 69 during neovascularization (FC ≥ 1.5; p ≤ 0.05), with several validated by western blot analyses. Expressions of 56/69 neovascular-specific proteins were confirmed in hypoxic HRECs with 23 regulated in the same direction as OIR neovascular retinas. These proteins control angiogenesis-related processes including matrix remodeling, cell migration, adhesion, and proliferation. RNAi and transfection overexpression studies confirmed that VASP and ECH1, showing the highest levels in hypoxic HRECs, promoted human umbilical vein (HUVEC) and HREC cell proliferation, while SNX1 and CD109, showing the lowest levels, inhibited their proliferation. These proteins are potential biomarkers and exploitable intervention tools for vascular-related disorders. The proteomics data set generated has been deposited to the ProteomeXchange/iProX Consortium with the Identifier:PXD029208.
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Affiliation(s)
- Manhong Xu
- Tianjin Key Laboratory of Retinal Functions and Diseases, Tianjin Branch of National Clinical Research Center for Ocular Disease, Eye Institute and School of Optometry, Tianjin Medical University Eye Hospital, Tianjin 300384, China
| | - Yilin Jiang
- Tianjin Key Laboratory of Retinal Functions and Diseases, Tianjin Branch of National Clinical Research Center for Ocular Disease, Eye Institute and School of Optometry, Tianjin Medical University Eye Hospital, Tianjin 300384, China
| | - Lin Su
- Tianjin Key Laboratory of Retinal Functions and Diseases, Tianjin Branch of National Clinical Research Center for Ocular Disease, Eye Institute and School of Optometry, Tianjin Medical University Eye Hospital, Tianjin 300384, China
| | - Xin Chen
- Tianjin Key Laboratory of Retinal Functions and Diseases, Tianjin Branch of National Clinical Research Center for Ocular Disease, Eye Institute and School of Optometry, Tianjin Medical University Eye Hospital, Tianjin 300384, China
| | - Xianfeng Shao
- State Key Laboratory of Proteomics, Beijing Proteome Research Center, Beijing Institute of Lifeomics, National Center for Protein Sciences (The PHOENIX Center, Beijing), Beijing 102206, China
| | - Vicki Ea
- Tianjin Key Laboratory of Retinal Functions and Diseases, Tianjin Branch of National Clinical Research Center for Ocular Disease, Eye Institute and School of Optometry, Tianjin Medical University Eye Hospital, Tianjin 300384, China
| | - Zhenying Shang
- Tianjin Key Laboratory of Retinal Functions and Diseases, Tianjin Branch of National Clinical Research Center for Ocular Disease, Eye Institute and School of Optometry, Tianjin Medical University Eye Hospital, Tianjin 300384, China
| | - Xiaomin Zhang
- Tianjin Key Laboratory of Retinal Functions and Diseases, Tianjin Branch of National Clinical Research Center for Ocular Disease, Eye Institute and School of Optometry, Tianjin Medical University Eye Hospital, Tianjin 300384, China
| | - Colin J Barnstable
- Tianjin Key Laboratory of Retinal Functions and Diseases, Tianjin Branch of National Clinical Research Center for Ocular Disease, Eye Institute and School of Optometry, Tianjin Medical University Eye Hospital, Tianjin 300384, China.,Department of Neural and Behavioral Sciences, Penn State College of Medicine, Hershey, Pennsylvania 17033-0850, United States
| | - Xiaorong Li
- Tianjin Key Laboratory of Retinal Functions and Diseases, Tianjin Branch of National Clinical Research Center for Ocular Disease, Eye Institute and School of Optometry, Tianjin Medical University Eye Hospital, Tianjin 300384, China
| | - Joyce Tombran-Tink
- Tianjin Key Laboratory of Retinal Functions and Diseases, Tianjin Branch of National Clinical Research Center for Ocular Disease, Eye Institute and School of Optometry, Tianjin Medical University Eye Hospital, Tianjin 300384, China.,Department of Neural and Behavioral Sciences, Penn State College of Medicine, Hershey, Pennsylvania 17033-0850, United States
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36
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Silencing Nogo-B improves the integrity of blood-retinal barrier in diabetic retinopathy via regulating Src, PI3K/Akt and ERK pathways. Biochem Biophys Res Commun 2021; 581:96-102. [PMID: 34662809 DOI: 10.1016/j.bbrc.2021.10.024] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2021] [Accepted: 10/10/2021] [Indexed: 12/22/2022]
Abstract
OBJECTIVE To examine the mechanisms of Nogo-B (RTN4B) in the protection of blood-retinal barrier in experimental diabetic retinopathy. METHODS The level of Nogo-B in vitreous and plasma samples was detected with ELISA. Diabetes was induced in Sprague-Dawley rats with intraperitoneal injection of streptozotocin. The rats were injected intravitreally with adeno-associated virus (AAV) for knockdown the expression of Nogo-B in retina or/and as AAV negative control. The permeability of blood-retinal barrier was detected with Rhodamine-B-dextran leakage assay. The expressions of Nogo-B, junctional proteins, inflammatory factors and signaling pathways were examined with Western blot and quantitative real-time PCR. RESULTS Nogo-B expression was significantly upregulated in clinical samples and experimental diabetic rat models. Under normal condition, Nogo-B knockdown resulted in the increased permeability of retinal blood vessels. In diabetic rat retinas, the vascular leakage was increased significantly, which was partially decreased by Nogo-B knockdown through increasing p/t-Src (Tyr529) and p/t-Akt (Ser473), and decreasing p/t-ERK1/2. CONCLUSION Nogo-B was increased in diabetic retinopathy and silencing Nogo-B is a promising therapy for diabetic retinopathy.
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37
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Matei N, Leahy S, Blair NP, Shahidi M. Assessment of retinal oxygen metabolism, visual function, thickness and degeneration markers after variable ischemia/reperfusion in rats. Exp Eye Res 2021; 213:108838. [PMID: 34774489 DOI: 10.1016/j.exer.2021.108838] [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: 09/10/2021] [Revised: 10/25/2021] [Accepted: 11/08/2021] [Indexed: 12/01/2022]
Abstract
After total retinal ischemia induced experimentally by ophthalmic vessel occlusion followed by reperfusion, studies have reported alterations in retinal oxygen metabolism (MO2), delivery (DO2), and extraction fraction (OEF), as well as visual dysfunction and cell loss. In the current study, under variable durations of ischemia/reperfusion, changes in these oxygen metrics, visual function, retinal thickness, and degeneration markers (gliosis and apoptosis) were assessed and related. Additionally, the prognostic value of MO2 for predicting visual function and retinal thickness outcomes was reported. Sixty-one rats were divided into 5 groups of ischemia duration (0 [sham], 60, 90, 120, or 180 min) and 2 reperfusion durations (1 h, 7 days). Phosphorescence lifetime and blood flow imaging, electroretinography, and optical coherence tomography were performed. MO2 reduction was related to visual dysfunction, retinal thinning, increased gliosis and apoptosis after 7-days reperfusion. Impairment in MO2 after 1-h reperfusion predicted visual function and retinal thickness outcomes after 7-days reperfusion. Since MO2 can be measured in humans, findings from analogous studies may find value in the clinical setting.
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Affiliation(s)
- Nathanael Matei
- Department of Ophthalmology, University of Southern California, Los Angeles, CA, United States
| | - Sophie Leahy
- Department of Ophthalmology, University of Southern California, Los Angeles, CA, United States
| | - Norman P Blair
- Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, Chicago, IL, United States
| | - Mahnaz Shahidi
- Department of Ophthalmology, University of Southern California, Los Angeles, CA, United States.
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38
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Ma P, Zhang P, Chen S, Shi W, Ye J, Chen S, Ju R, Liu B, Zheng Y, Liu Y. Immune Cell Landscape of Patients With Diabetic Macular Edema by Single-Cell RNA Analysis. Front Pharmacol 2021; 12:754933. [PMID: 34594230 PMCID: PMC8476792 DOI: 10.3389/fphar.2021.754933] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2021] [Accepted: 08/30/2021] [Indexed: 12/13/2022] Open
Abstract
Purpose: We performed single-cell RNA sequencing (scRNA-seq), an unbiased and high-throughput single cell technology, to determine phenotype and function of peripheral immune cells in patients with diabetic macular edema (DME). Methods: Peripheral blood mononuclear cells (PBMCs) were isolated from DME patients and healthy controls (HC). The single-cell samples were loaded on the Chromium platform (10x Genomics) for sequencing. R package Seurat v3 was used for data normalizing, clustering, dimensionality reduction, differential expression analysis, and visualization. Results: We constructed a single-cell RNA atlas comprising 57,650 PBMCs (24,919 HC, 32,731 DME). We divided all immune cells into five major immune cell lineages, including monocytes (MC), T cells (TC), NK cells (NK), B cells (BC), and dendritic cells (DC). Our differential expression gene (DEG) analysis showed that MC was enriched of genes participating in the cytokine pathway and inflammation activation. We further subdivided MC into five subsets: resting CD14++ MC, proinflammatory CD14++ MC, intermediate MC, resting CD16++ MC and pro-inflammatory CD16++ MC. Remarkably, we revealed that the proinflammatory CD14++ monocytes predominated in promoting inflammation, mainly by increasingly production of inflammatory cytokines (TNF, IL1B, and NFKBIA) and chemokines (CCL3, CCL3L1, CCL4L2, CXCL2, and CXCL8). Gene Ontology (GO) and pathway analysis of the DEGs demonstrated that the proinflammatory CD14++ monocytes, especially in DME patients, upregulated inflammatory pathways including tumor necrosis factor-mediated signaling pathway, I-kappaB kinase/NF-kappaB signaling, and toll-like receptor signaling pathway. Conclusion: In this study, we construct the first immune landscape of DME patients with T2D and confirmed innate immune dysregulation in peripheral blood based on an unbiased scRNA-seq approach. And these results demonstrate potential target cell population for anti-inflammation treatments.
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Affiliation(s)
- Pengjuan Ma
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China.,Guangzhou Regenerative Medicine and Health Guangdong Laboratory, Guangzhou, China.,Research Unit of Ocular Development and Regeneration, Chinese Academy of Medical Sciences, Guangzhou, China
| | - Ping Zhang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Shuxia Chen
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Wen Shi
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China.,Guangzhou Regenerative Medicine and Health Guangdong Laboratory, Guangzhou, China.,Research Unit of Ocular Development and Regeneration, Chinese Academy of Medical Sciences, Guangzhou, China
| | - Jinguo Ye
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China.,Guangzhou Regenerative Medicine and Health Guangdong Laboratory, Guangzhou, China.,Research Unit of Ocular Development and Regeneration, Chinese Academy of Medical Sciences, Guangzhou, China
| | - Shida Chen
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China.,Guangzhou Regenerative Medicine and Health Guangdong Laboratory, Guangzhou, China.,Research Unit of Ocular Development and Regeneration, Chinese Academy of Medical Sciences, Guangzhou, China
| | - Rong Ju
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Bingqian Liu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Yingfeng Zheng
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China.,Guangzhou Regenerative Medicine and Health Guangdong Laboratory, Guangzhou, China.,Research Unit of Ocular Development and Regeneration, Chinese Academy of Medical Sciences, Guangzhou, China
| | - Yizhi Liu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China.,Guangzhou Regenerative Medicine and Health Guangdong Laboratory, Guangzhou, China.,Research Unit of Ocular Development and Regeneration, Chinese Academy of Medical Sciences, Guangzhou, China
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Abstract
Advances in retinal imaging are enabling researchers and clinicians to make precise noninvasive measurements of the retinal vasculature in vivo. This includes measurements of capillary blood flow, the regulation of blood flow, and the delivery of oxygen, as well as mapping of perfused blood vessels. These advances promise to revolutionize our understanding of vascular regulation, as well as the management of retinal vascular diseases. This review provides an overview of imaging and optical measurements of the function and structure of the ocular vasculature. We include general characteristics of vascular systems with an emphasis on the eye and its unique status. The functions of vascular systems are discussed, along with physical principles governing flow and its regulation. Vascular measurement techniques based on reflectance and absorption are briefly introduced, emphasizing ways of generating contrast. One of the prime ways to enhance contrast within vessels is to use techniques sensitive to the motion of cells, allowing precise measurements of perfusion and blood velocity. Finally, we provide a brief introduction to retinal vascular diseases.
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Affiliation(s)
- Stephen A Burns
- Indiana University School of Optometry, Bloomington, Indiana 47405, USA; , ,
| | - Ann E Elsner
- Indiana University School of Optometry, Bloomington, Indiana 47405, USA; , ,
| | - Thomas J Gast
- Indiana University School of Optometry, Bloomington, Indiana 47405, USA; , ,
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40
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Taylor AW, Hsu S, Ng TF. The Role of Retinal Pigment Epithelial Cells in Regulation of Macrophages/Microglial Cells in Retinal Immunobiology. Front Immunol 2021; 12:724601. [PMID: 34484232 PMCID: PMC8414138 DOI: 10.3389/fimmu.2021.724601] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2021] [Accepted: 07/28/2021] [Indexed: 12/28/2022] Open
Abstract
The ocular tissue microenvironment is immune privileged and uses several mechanisms of immunosuppression to prevent the induction of inflammation. Besides being a blood-barrier and source of photoreceptor nutrients, the retinal pigment epithelial cells (RPE) regulate the activity of immune cells within the retina. These mechanisms involve the expression of immunomodulating molecules that make macrophages and microglial cells suppress inflammation and promote immune tolerance. The RPE have an important role in ocular immune privilege to regulate the behavior of immune cells within the retina. Reviewed is the current understanding of how RPE mediate this regulation and the changes seen under pathological conditions.
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Affiliation(s)
- Andrew W Taylor
- Department of Ophthalmology, Boston University School of Medicine, Boston, MA, United States
| | - Samuel Hsu
- Department of Ophthalmology, Boston University School of Medicine, Boston, MA, United States
| | - Tat Fong Ng
- Department of Ophthalmology, Boston University School of Medicine, Boston, MA, United States
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41
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Hu J, Zhu M, Li D, Wu Q, Le YZ. VEGF as a Direct Functional Regulator of Photoreceptors and Contributing Factor to Diabetes-Induced Alteration of Photoreceptor Function. Biomolecules 2021; 11:biom11070988. [PMID: 34356612 PMCID: PMC8301820 DOI: 10.3390/biom11070988] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Revised: 07/02/2021] [Accepted: 07/03/2021] [Indexed: 12/15/2022] Open
Abstract
Vascular endothelial growth factor (VEGF) is a major therapeutic target for blood-retina barrier (BRB) breakdown in diabetic retinopathy (DR), age-related macular degeneration (AMD), and other hypoxic retinal vascular disorders. To determine whether VEGF is a direct regulator of retinal neuronal function and its potential role in altering vision during the progression of DR, we examined the immediate impact of recombinant VEGF (rVEGF) on photoreceptor function with electroretinography in C57BL6 background wild-type (WT) and Akita spontaneous diabetic mice. Shortly after intravitreal injections, rVEGF caused a significant reduction of scotopic ERG a-wave and b-wave amplitudes and photopic ERG b-wave amplitudes in a dose-dependent manner in dark-adapted 1.5-mo-old WT mice. Compared with WT controls, 5-mo-old Akita spontaneous diabetic mice demonstrated a significant reduction in scotopic ERG a-wave and b-wave amplitudes and photopic ERG b-wave amplitudes. However, the effect of rVEGF altered photoreceptor function in WT controls was diminished in 5-mo-old Akita spontaneous diabetic mice. In conclusion, our results suggest that VEGF is a direct functional regulator of photoreceptors and VEGF up-regulation in DR is a contributing factor to diabetes-induced alteration of photoreceptor function. This information is critical to the understanding of the therapeutic effect and to the care of anti-VEGF drug-treated patients for BRB breakdown in DR, AMD, and other hypoxic retinal vascular disorders.
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Affiliation(s)
- Jianyan Hu
- Section of Endocrinology, Diabetes and Metabolism, Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA; (J.H.); (M.Z.); (D.L.)
- Department of Ophthalmology, Shanghai Jiao Tong University Affiliated Sixth People’s Hospital, Shanghai 200233, China
| | - Meili Zhu
- Section of Endocrinology, Diabetes and Metabolism, Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA; (J.H.); (M.Z.); (D.L.)
| | - Dai Li
- Section of Endocrinology, Diabetes and Metabolism, Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA; (J.H.); (M.Z.); (D.L.)
- School of Optometry, Hubei University of Science and Technology, Xianning 437100, China
| | - Qiang Wu
- Department of Ophthalmology, Shanghai Jiao Tong University Affiliated Sixth People’s Hospital, Shanghai 200233, China
- Shanghai Key Laboratory of Diabetes Mellitus, Shanghai 200233, China
- Correspondence: (Q.W.); (Y.-Z.L.)
| | - Yun-Zheng Le
- Section of Endocrinology, Diabetes and Metabolism, Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA; (J.H.); (M.Z.); (D.L.)
- Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
- Department of Ophthalmology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
- Harold Hamm Diabetes Center, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
- Correspondence: (Q.W.); (Y.-Z.L.)
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Mateos-Olivares M, García-Onrubia L, Valentín-Bravo FJ, González-Sarmiento R, Lopez-Galvez M, Pastor JC, Usategui-Martín R, Pastor-Idoate S. Rho-Kinase Inhibitors for the Treatment of Refractory Diabetic Macular Oedema. Cells 2021; 10:cells10071683. [PMID: 34359853 PMCID: PMC8307715 DOI: 10.3390/cells10071683] [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: 05/17/2021] [Revised: 06/26/2021] [Accepted: 06/29/2021] [Indexed: 12/13/2022] Open
Abstract
Diabetic macular oedema (DMO) is one of the leading causes of vision loss associated with diabetic retinopathy (DR). New insights in managing this condition have changed the paradigm in its treatment, with intravitreal injections of antivascular endothelial growth factor (anti-VEGF) having become the standard therapy for DMO worldwide. However, there is no single standard therapy for all patients DMO refractory to anti-VEGF treatment; thus, further investigation is still needed. The key obstacles in developing suitable therapeutics for refractory DMO lie in its complex pathophysiology; therefore, there is an opportunity for further improvements in the progress and applications of new drugs. Previous studies have indicated that Rho-associated kinase (Rho-kinase/ROCK) is an essential molecule in the pathogenesis of DMO. This is why the Rho/ROCK signalling pathway has been proposed as a possible target for new treatments. The present review focuses on the recent progress on the possible role of ROCK and its therapeutic potential in DMO. A systematic literature search was performed, covering the years 1991 to 2021, using the following keywords: "rho-Associated Kinas-es", "Diabetic Retinopathy", "Macular Edema", "Ripasudil", "Fasudil" and "Netarsudil". Better insight into the pathological role of Rho-kinase/ROCK may lead to the development of new strategies for refractory DMO treatment and prevention.
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Affiliation(s)
- Milagros Mateos-Olivares
- Department of Ophthalmology, Hospital Clínico Universitario de Valladolid, 47003 Valladolid, Spain; (M.M.-O.); (L.G.-O.); (F.J.V.-B.); (M.L.-G.); (J.C.P.)
| | - Luis García-Onrubia
- Department of Ophthalmology, Hospital Clínico Universitario de Valladolid, 47003 Valladolid, Spain; (M.M.-O.); (L.G.-O.); (F.J.V.-B.); (M.L.-G.); (J.C.P.)
- Department of Ophthalmology, St Thomas’ Hospital, London SE1 7EH, UK
| | - Fco. Javier Valentín-Bravo
- Department of Ophthalmology, Hospital Clínico Universitario de Valladolid, 47003 Valladolid, Spain; (M.M.-O.); (L.G.-O.); (F.J.V.-B.); (M.L.-G.); (J.C.P.)
| | - Rogelio González-Sarmiento
- Area of Infectious, Inflammatory and Metabolic Disease, Institute of Biomedical Research of Salamanca (IBSAL), 37007 Salamanca, Spain;
- Institute of Molecular and Cellular Biology of Cancer (IBMCC), University of Salamanca-CSIC, 37007 Salamanca, Spain
| | - Maribel Lopez-Galvez
- Department of Ophthalmology, Hospital Clínico Universitario de Valladolid, 47003 Valladolid, Spain; (M.M.-O.); (L.G.-O.); (F.J.V.-B.); (M.L.-G.); (J.C.P.)
- Retina Group, IOBA (Institute of Applied Ophthalmobiology), University of Valladolid, 47002 Valladolid, Spain
- Cooperative Network for Research in Ophthalmology Oftared, National Institute of Health Carlos III, 28220 Madrid, Spain
| | - J. Carlos Pastor
- Department of Ophthalmology, Hospital Clínico Universitario de Valladolid, 47003 Valladolid, Spain; (M.M.-O.); (L.G.-O.); (F.J.V.-B.); (M.L.-G.); (J.C.P.)
- Retina Group, IOBA (Institute of Applied Ophthalmobiology), University of Valladolid, 47002 Valladolid, Spain
- Cooperative Network for Research in Ophthalmology Oftared, National Institute of Health Carlos III, 28220 Madrid, Spain
| | - Ricardo Usategui-Martín
- Institute of Molecular and Cellular Biology of Cancer (IBMCC), University of Salamanca-CSIC, 37007 Salamanca, Spain
- Retina Group, IOBA (Institute of Applied Ophthalmobiology), University of Valladolid, 47002 Valladolid, Spain
- Correspondence: (R.U.-M.); (S.P.-I.); Tel.: +34-983-423-559
| | - Salvador Pastor-Idoate
- Department of Ophthalmology, Hospital Clínico Universitario de Valladolid, 47003 Valladolid, Spain; (M.M.-O.); (L.G.-O.); (F.J.V.-B.); (M.L.-G.); (J.C.P.)
- Retina Group, IOBA (Institute of Applied Ophthalmobiology), University of Valladolid, 47002 Valladolid, Spain
- Cooperative Network for Research in Ophthalmology Oftared, National Institute of Health Carlos III, 28220 Madrid, Spain
- Correspondence: (R.U.-M.); (S.P.-I.); Tel.: +34-983-423-559
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Tonade D, Kern TS. Photoreceptor cells and RPE contribute to the development of diabetic retinopathy. Prog Retin Eye Res 2021; 83:100919. [PMID: 33188897 PMCID: PMC8113320 DOI: 10.1016/j.preteyeres.2020.100919] [Citation(s) in RCA: 85] [Impact Index Per Article: 28.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2020] [Revised: 10/27/2020] [Accepted: 10/31/2020] [Indexed: 12/26/2022]
Abstract
Diabetic retinopathy (DR) is a leading cause of blindness. It has long been regarded as vascular disease, but work in the past years has shown abnormalities also in the neural retina. Unfortunately, research on the vascular and neural abnormalities have remained largely separate, instead of being integrated into a comprehensive view of DR that includes both the neural and vascular components. Recent evidence suggests that the most predominant neural cell in the retina (photoreceptors) and the adjacent retinal pigment epithelium (RPE) play an important role in the development of vascular lesions characteristic of DR. This review summarizes evidence that the outer retina is altered in diabetes, and that photoreceptors and RPE contribute to retinal vascular alterations in the early stages of the retinopathy. The possible molecular mechanisms by which cells of the outer retina might contribute to retinal vascular damage in diabetes also are discussed. Diabetes-induced alterations in the outer retina represent a novel therapeutic target to inhibit DR.
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Affiliation(s)
- Deoye Tonade
- Department of Pharmacology, Case Western Reserve University, Cleveland, OH, USA
| | - Timothy S Kern
- Department of Pharmacology, Case Western Reserve University, Cleveland, OH, USA; Veterans Administration Medical Center Research Service, Cleveland, OH, USA; Gavin Herbert Eye Institute, University of California Irvine, Irvine, CA, USA; Veterans Administration Medical Center Research Service, Long Beach, CA, USA.
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Baicalein, Baicalin, and Wogonin: Protective Effects against Ischemia-Induced Neurodegeneration in the Brain and Retina. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2021; 2021:8377362. [PMID: 34306315 PMCID: PMC8263226 DOI: 10.1155/2021/8377362] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 06/08/2021] [Accepted: 06/19/2021] [Indexed: 12/17/2022]
Abstract
Ischemia is a common pathological condition present in many neurodegenerative diseases, including ischemic stroke, retinal vascular occlusion, diabetic retinopathy, and glaucoma, threatening the sight and lives of millions of people globally. Ischemia can trigger excessive oxidative stress, inflammation, and vascular dysfunction, leading to the disruption of tissue homeostasis and, ultimately, cell death. Current therapies are very limited and have a narrow time window for effective treatment. Thus, there is an urgent need to develop more effective therapeutic options for ischemia-induced neural injuries. With emerging reports on the pharmacological properties of natural flavonoids, these compounds present potent antioxidative, anti-inflammatory, and antiapoptotic agents for the treatment of ischemic insults. Three major active flavonoids, baicalein, baicalin, and wogonin, have been extracted from Scutellaria baicalensis Georgi (S. baicalensis); all of which are reported to have low cytotoxicity. They have been demonstrated to exert promising pharmacological capabilities in preventing cell and tissue damage. This review focuses on the therapeutic potentials of these flavonoids against ischemia-induced neurotoxicity and damage in the brain and retina. The bioactivity and bioavailability of baicalein, baicalin, and wogonin are also discussed. It is with hope that the therapeutic potential of these flavonoids can be utilized and developed as natural treatments for ischemia-induced injuries of the central nervous system (CNS).
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Changes in retinal layers in type 1 diabetes mellitus without retinopathy measured by spectral domain and swept source OCTs. Sci Rep 2021; 11:10427. [PMID: 34001996 PMCID: PMC8129145 DOI: 10.1038/s41598-021-89992-w] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Accepted: 05/05/2021] [Indexed: 11/10/2022] Open
Abstract
To evaluate changes in inner retinal layer (IRL) thicknesses in patients with type 1 diabetes mellitus (DM1) with no diabetic retinopathy (DR) using two different optical coherence tomography (OCT) devices. Ninety DM1 and 60 healthy eyes were evaluated using spectral domain (SD)-OCT and swept source (SS)-OCT to measure changes in the retinal nerve fiber layer (RNFL), ganglion cell layer (GCL), inner plexiform layer (IPL) and inner nuclear layer (INL) thicknesses in all Early Treatment of Diabetic Retinopathy Study (ETDRS) macular areas. Functional tests were performed in both groups, including ETDRS with 100, 2.5 and 1.25% contrast, and color vision. The mean ages were 42.93 ± 13.62 and 41.52 ± 13.05 years in the diabetic and control groups, respectively. Visual acuity (VA) with ETDRS 1.25% was lower in the DM1 patients. Both ETDRS 2.5% and color vision were lower in the DM1 group but did not reach statistical significance. Retinal thicknesses in the central area and in the vertical outer areas were higher in the DM1 group. Differences were found in the IRL with no changes in the outer ones. Long-term DM1 patients with no DR maintained visual function, with a decrease in VA with 1.25% ETDRS contrast. Macular thickness measurements were higher using Spectralis SD-OCT than DRI Triton SS-OCT, and DM1 patients had a decrease in IRL thickness, especially in the GCL at the parafoveal level, generating thinning of the RNFL in the peripheral areas. There were no differences in outer retinal layer (ORL) thickness.
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Fang M, Wan W, Li Q, Wan W, Long Y, Liu H, Yang X. Asiatic acid attenuates diabetic retinopathy through TLR4/MyD88/NF-κB p65 mediated modulation of microglia polarization. Life Sci 2021; 277:119567. [PMID: 33965378 DOI: 10.1016/j.lfs.2021.119567] [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] [Received: 12/02/2020] [Revised: 04/20/2021] [Accepted: 04/25/2021] [Indexed: 12/12/2022]
Abstract
AIM This study aimed to evaluate the effects of Asiatic acid (AA), a naturally occurring compound of pentacyclic triterpenoid, on the pathological processes of diabetic retinopathy (DR). METHODS SD rats were induced to develop early DR by intraperitoneal injection of STZ (60 mg/kg). Four weeks after injection, the diabetic rats were orally administrated with 37.5 mg/kg or 75 mg/kg AA every day for four weeks. The integrity of blood-retinal barrier (BRB) was measured by Evans blue staining. The polarization of microglia was determined by real-time PCR, western blot, and ELISA assays. The inner BRB (iBRB) or outer BRB (oBRB) breakdown was induced in human retinal endothelial cells or APRE19 cells through co-culture with high glucose and LPS-stimulated microglia BV2 cells. The damage to the iBRB and oBRB was measured using transendothelial/transepithelial electrical resistance (TEER/TER) and FITC-conjugated dextran cell permeability assays. KEY FINDINGS Results demonstrated that AA alleviated BRB breakdown, as evidenced by decreased protein expression of occludin, claudin-5, and ZO-1. Furthermore, AA treatment suppressed inflammation and M1 polarization, while it increased M2 polarization in the retina of DR rats. In vitro, the iBRB or oBRB breakdown was alleviated by AA. LPS-induced M1-polarization of BV2 cells under high glucose condition was also repressed through AA administration. Finally, we demonstrated that AA weakened the TLR4/MyD88/NF-κB p65 signaling pathway both in vivo and in vitro. SIGNIFICANCE AA ameliorated early DR by regulating microglia polarization via the TLR4/MyD88/NF-κB p65 pathway. These data indicate that AA is a potential candidate for DR treatment.
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Affiliation(s)
- Mengyuan Fang
- Department of Ophthalmology, The First Affiliated Hospital of Zhengzhou University, 450052 Zhengzhou, Henan, China
| | - Wencui Wan
- Department of Ophthalmology, The First Affiliated Hospital of Zhengzhou University, 450052 Zhengzhou, Henan, China
| | - Qiuming Li
- Department of Ophthalmology, The First Affiliated Hospital of Zhengzhou University, 450052 Zhengzhou, Henan, China
| | - Weiwei Wan
- Department of Ophthalmology, The First Affiliated Hospital of Zhengzhou University, 450052 Zhengzhou, Henan, China
| | - Yang Long
- Department of Ophthalmology, The First Affiliated Hospital of Zhengzhou University, 450052 Zhengzhou, Henan, China
| | - Hongzhuo Liu
- Department of Ophthalmology, The First Affiliated Hospital of Zhengzhou University, 450052 Zhengzhou, Henan, China
| | - Xin Yang
- Department of Ophthalmology, The First Affiliated Hospital of Zhengzhou University, 450052 Zhengzhou, Henan, China.
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Ţălu Ş, Nicoara SD. Malfunction of outer retinal barrier and choroid in the occurrence and progression of diabetic macular edema. World J Diabetes 2021; 12:437-452. [PMID: 33889289 PMCID: PMC8040083 DOI: 10.4239/wjd.v12.i4.437] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Revised: 02/23/2021] [Accepted: 03/24/2021] [Indexed: 02/06/2023] Open
Abstract
Diabetic macular edema (DME) is the most common cause of vision loss in diabetic retinopathy, affecting 1 in 15 patients with diabetes mellitus (DM). The disruption of the inner blood-retina barrier (BRB) has been largely investigated and attributed the primary role in the pathogenesis and progression in DME, but there is increasing evidence regarding the role of outer BRB, separating the RPE from the underlying choriocapillaris, in the occurrence and evolution of DME. The development of novel imaging technologies has led to major improvement in the field of in vivo structural analysis of the macula allowing us to delve deeper into the pathogenesis of DME and expanding our vision regarding this condition. In this review we gathered the results of studies that investigated specific outer BRB optical coherence tomography parameters in patients with DM with the aim to outline the current status of its role in the pathogenesis and progression of DME and identify new research pathways contributing to the advancement of knowledge in the understanding of this condition.
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Affiliation(s)
- Ştefan Ţălu
- Directorate of Research, Development and Innovation Management (DMCDI), Technical University of Cluj-Napoca, Cluj-Napoca 400020, Romania
| | - Simona Delia Nicoara
- Department of Ophthalmology, Iuliu Haţieganu University of Medicine and Pharmacy, Cluj-Napoca 400012, Romania
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Astaxanthin mediated regulation of VEGF through HIF1α and XBP1 signaling pathway: An insight from ARPE-19 cell and streptozotocin mediated diabetic rat model. Exp Eye Res 2021; 206:108555. [PMID: 33789142 DOI: 10.1016/j.exer.2021.108555] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Revised: 03/08/2021] [Accepted: 03/23/2021] [Indexed: 11/21/2022]
Abstract
Breakdown of outer blood-retina barrier (BRB) has been associated with the pathogenesis of diabetic retinopathy (DR) and diabetic macular edema (DME). Vascular endothelial growth factor (VEGF) might play a detrimental role in the pathogenesis of DME, a major clinical manifestation of DR. In the present study, we investigated the inhibitory mechanism of astaxanthin on VEGF and its upstream signaling pathways under in vitro and in vivo conditions. Astaxanthin has been observed to downregulate VEGF expression under hyperglycemic (HG) and CoCl2 induced hypoxic conditions in ARPE-19 cells. There were compelling pieces of evidence for the involvement of transcription factors like HIF1α and XBP1 in the upregulation of VEGF under HG and hypoxic conditions. Thus, we investigated the role of astaxanthin in the expression and nuclear translocation of HIF1α and XBP1. The activation and translocation of HIF1α and XBP1 induced by HG or CoCl2 conditions were hindered by astaxanthin. Additionally, treatment with HIF1α siRNA and IRE1 inhibitor STF-083010 also inhibited the expression of VEGF induced by HG and CoCl2 conditions. These results indicated that the anti-VEGF property of astaxanthin might be associated with the downregulation of HIF1α and XBP1. Furthermore, astaxanthin mitigated the enhanced migration of retinal pigment epithelial (RPE) cells under DR conditions. As well, astaxanthin protected disorganization of zona occludin-1 (ZO-1) tight junction protein in RPE and reduced HG or hypoxic induced permeability of RPE cells. In streptozotocin-induced diabetic rat model, astaxanthin reduced the expression of HIF1α, XBP1, and VEGF as well as protected the abnormalities in the retinal layers induced by diabetes condition. Thus, astaxanthin may be used as a potential nutraceutical to prevent or treat retinal dysfunction in diabetic patients.
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El-Mansi AA, Al-Kahtani MA, Rady AM, El-Bealy EA, Al-Asmari AM. Vitamin A and Daucus carota root extract mitigate STZ-induced diabetic retinal degeneration in Wistar albino rats by modulating neurotransmission and downregulation of apoptotic pathways. J Food Biochem 2021; 45:e13688. [PMID: 33687088 DOI: 10.1111/jfbc.13688] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2020] [Revised: 02/14/2021] [Accepted: 02/21/2021] [Indexed: 12/17/2022]
Abstract
The objective of our study was to explore the deleterious effects of diabetes on the visual functions of the retina and to address whether the administration of vitamin A and carrot root extract (CE) confer retinal protection in hyperglycemic rats via modulation of oxidative stress, biochemical alternations, and retinal neurotransmission. Fifty male Wistar albino rats weighing 180 ± 12.41 g were randomized into five groups (n = 10): controls, diabetic group (injected with 40 mg/kg dissolved in 0.1 sodium citrate buffer), diabetic group treated with vitamin A (2,500 IU/kg, low dose), diabetic group treated with vitamin (5,000 IU/kg, high dose), and diabetic groups administered CE (200 mg/kg/every other day). Our findings showed that, compared to controls, diabetic rats showed a significant decrease in their retinal thickness, increased apoptotic ganglion cells, and a noticeable degeneration of their synaptic layers. The inner retina displayed increased activity of neovascularization; however, the outer retina exhibited vacuolar degeneration of the photoreceptor cell layer. Our biochemical assessments showed reduced levels of CAT, SOD, and GST along with increased lipid peroxidation. Concurrently, cellular angiogenic and stress markers were significantly elevated associated with increased apoptotic activities as evidenced by increased expressions of annexin-V and PARP. Furthermore, the neurotransmitter content of the retina was altered in diabetic rats compared to controls and diabetic-treated groups. Paradoxically, vitamin A and CE supplementation attenuate these retinal insults in diabetic animals and normalized aforementioned assayed parameters; evidencing that both treatments exerted ameliorative impacts and restored visual functions by diminishing oxidative stress and neuronal degeneration. PRACTICAL APPLICATIONS: Diabetes is a complex disease that involves various physiological perturbations especially visual functions. In our study, we showed that vitamin A and carrot root extract (CE) confer remarkable protection against retinal degeneration in STZ-induced diabetic rats. Our findings showed that the chemical and phytochemical ingredients of the vitamin A and CE substantially attenuated the histopathological changes, oxidative stress, inflammatory reactions, and cellular death in diabetic rats. These favorable changes are attributable to the high content of retinoic acid, carotenoids, and phenolic compounds that effectively regulates the production of visual pigments, increases the antioxidant defense system, and diminishes the pro-inflammatory and apoptotic pathways. Thus, the nutritional values of vitamin A and CE represent promising therapeutic choices to mitigate the retinal-induced diabetic insults.
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Affiliation(s)
- Ahmed A El-Mansi
- Biology Department, Faculty of Science, King Khalid University, Abha, Saudi Arabia.,Zoology Department, Faculty of Science, Mansoura University, Mansoura, Egypt
| | - M A Al-Kahtani
- Biology Department, Faculty of Science, King Khalid University, Abha, Saudi Arabia
| | - Ahmed M Rady
- Biology Department, Faculty of Science, King Saud University, Riyadh, Saudi Arabia
| | - Eman A El-Bealy
- Biology Department, Faculty of Science, King Khalid University, Abha, Saudi Arabia
| | - A M Al-Asmari
- Biology Department, Faculty of Science, King Khalid University, Abha, Saudi Arabia
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50
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Alam K, Akhter Y. The Impacts of Unfolded Protein Response in the Retinal Cells During Diabetes: Possible Implications on Diabetic Retinopathy Development. Front Cell Neurosci 2021; 14:615125. [PMID: 33613197 PMCID: PMC7886690 DOI: 10.3389/fncel.2020.615125] [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: 10/09/2020] [Accepted: 12/23/2020] [Indexed: 11/25/2022] Open
Abstract
Diabetic retinopathy (DR) is a vision-threatening, chronic, and challenging eye disease in the diabetic population. Despite recent advancements in the clinical management of diabetes, DR remains the major cause of blindness in working-age adults. A better understanding of the molecular and cellular basis of DR development will aid in identifying therapeutic targets. Emerging pieces of evidence from recent research in the field of ER stress have demonstrated a close association between unfolded protein response (UPR)-associated cellular activities and DR development. In this minireview article, we shall provide an emerging understating of how UPR influences DR pathogenesis at the cellular level.
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Affiliation(s)
- Kaiser Alam
- Department of Biotechnology, School of Life Sciences, Babasaheb Bhimrao Ambedkar University, Lucknow, India
| | - Yusuf Akhter
- Department of Biotechnology, School of Life Sciences, Babasaheb Bhimrao Ambedkar University, Lucknow, India
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